Radiography examination [10 ed.] 9780071833080, 0071833080, 9780071833103, 0071833102

Citation preview

PHOTOSTIMULABLEPHOSPHORSCREENLAYERS

COMPARISONSBETWEENLARGEANDSMALLIMAGEINTENSIFIERFOV

• • • • • •

Larger Field of View

Protective coat BaFX:Eu 2+ phosphors in binder material Re ective backing Polyester base support material Antistatic layer Lead foil backing

• Focal point closer to output screen • Less magni cation of perceived image • Brighter image; less exposure required

Smaller Field of View

• Focal point farther from output screen • Magni ed image • Less brightness; more exposure required

TERMINOLOGYCOMPARISON S/F Imaging

CR/DR Imaging

Latitude Contrast Receptor exposure Recorded detail

Dynamic range Grayscale Receptor exposure Spatial resolution

Radiation Weighting (Wr) Factors

CRSPATIALFREQUENCY/RESOLUTION

• • • • •

CR spatial frequency/resolution increases as

Tissue Weighting (Wt) Factors

• PSP crystal size decreases • Laser beam size decreases • Monitor matrix size increases

• • • • •

PICTUREARCHIVINGANDCOMMUNICATIONSYSTEM PACS capabilities:

• • • •

• • • •

Underexposure Incorrect processing algorithm Excess SR; inadequate collimation Grid misalignment; cuto

BEAMRESTRICTION

CR Artifact

Cause

• • • •

Exposure to scattered or environmental radiation Delayed processing Unused and not erased be ore use Incomplete erasure

Typical Image Matrix Sizes Used in Imaging

• • • •

Nuclear medicine Digital subtraction angiography Computed tomography Chest radiography

128 × 1,024 × 512 × 2,048 ×

128 1,024 512 2,048

ADVANTAGESOFDIGITALFLUOROSCOPYPHOTOSPOTS • • • •

Main-chain, double-side rail break Main-chain, single-side rail break Main-chain breakage, cross-linking Base damage, point mutations

• Elective scheduling/10-day rule • Patient questionnaire • Posting

Brightness/density changes with changes in window level Contrast changes with changes in window width Wide dynamic range Signi cant exposure latitude Fading with delayed processing PSPs are very sensitive to fog

Fog Image ading Black spots Slight additional anatomic image

0.01 0.05 0.05 0.12 0.20

Skin Thyroid Breast Lung Gonads

WAYSTOREDUCERISKTORECENTLYFERTILIZEDOVUM

ELECTRONICIMAGING • • • • • •

1 2 10 20 20

TYPESOFDNADAMAGE

Image acquisition Image display and interpretation Image archival and retrieval Image communication

CAUSESOFCRGRAININESS • • • •

X- or gamma Protons Neutrons: 10–100 keV Neutrons: 100 keV–2 MeV Alpha particles

Decreased patient dose Postprocessing capability “Road-mapping” capability No chemical processing needed

GONADALSHIELDING Gonadal shielding should be used if:

• T e gonads lie in, or within 5 cm of, the collimated eld • T e patient has reasonable reproductive potential • Diagnostic objectives permit

• Reduces patient dose • Improves image quality

Beam Restrictor Types

• Collimator • Cone • Aperture diaphragm Abbreviations ADC APR CCD CR DEL DICOM DIP DQE EDR HIS IP MTF PACS PD PIP PMT PSL PSP RIS SF SNR SPS TFT

Analog-to-digital converter Anatomically programmed radiography Charge coupled device Computed radiography Detector element Digital imaging and communications in medicine Distal interphalangeal joint Detective quantum e ciency Exposure data recognition Hospital in ormation system Image plate Modulation trans er unction Picture archiving and communication system Photodiode Proximal interphalangeal joint Photomultiplier tube Photostimulable luminescence Photostimulable phosphor Radiology in ormation system Screen/f lm Signal-to-noise ratio Storage phosphor screen Thin f lm transistor

TENTH EDITION

LANGE Q &A

™

RADIO GRAP HY EXAMINATIO N D. A. Saia, MA, RT(R) (M) Radiography Educator and Consultant Adjunct Pro essor, Concordia College Bronxville, New York

New York Chicago Mexico City Milan

San Francisco Athens London New Delhi Singapore Sydney

Madrid oronto

Copyright © 2016 by McGraw-Hill Education. All rights reserved. Except as permitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher, with the exception that the program listings may be entered, stored, and executed in a computer system, but they may not be reproduced for publication. ISBN: 978-0-07-183308-0 MHID: 0-07-183308-0 The material in this eBook also appears in the print version of this title: ISBN: 978-0-07-183310-3, MHID: 0-07-183310-2. eBook conversion by codeMantra Version 1.0 All trademarks are trademarks of their respective owners. Rather than put a trademark symbol after every occurrence of a trademarked name, we use names in an editorial fashion only, and to the bene t of the trademark owner, with no intention of infringement of the trademark. Where such designations appear in this book, they have been printed with initial caps. McGraw-Hill Education eBooks are available at special quantity discounts to use as premiums and sales promotions or for use in corporate training programs. To contact a representative, please visit the Contact Us page at www.mhprofessional.com. Previous editions Copyright © 2012, 2011, 2008, 2006 by The McGraw-Hill Companies, Inc. Lange Q&ATM is a trademark of McGraw-Hill Education. Notice Medicine is an ever-changing science. As new research and clinical experience broaden our knowledge, changes in treatment and drug therapy are required. The authors and the publisher of this work have checked with sources believed to be reliable in their efforts to provide information that is complete and generally in accord with the standards accepted at the time of publication. However, in view of the possibility of human error or changes in medical sciences, neither the authors nor the publisher nor any other party who has been involved in the preparation or publication of this work warrants that the information contained herein is in every respect accurate or complete, and they disclaim all responsibility for any errors or omissions or for the results obtained from use of the information contained in this work. Readers are encouraged to con rm the information contained herein with other sources. For example and in particular, readers are advised to check the product information sheet included in the package of each drug they plan to administer to be certain that the information contained in this work is accurate and that changes have not been made in the recommended dose or in the contraindications for administration. This recommendation is of particular importance in connection with new or infrequently used drugs. The following gures were originally published in Saia DA, Radiography PREP: Program Review and Examination Preparation, 5th ed. New York: McGraw-Hill, 2009 and are reproduced with permission from McGraw-Hill: Figures 2-47, 2-49, 2-50, 2-52, 2-55, 2-58, 3-5, 4-19, 4-21, 4-22, 4-24, 5-1, 5-3, 5-10, 5-12, 6-14, 6-15, 6-17, 6-22, and 7-24. TERMS OF USE This is a copyrighted work and McGraw-Hill Education and its licensors reserve all rights in and to the work. Use of this work is subject to these terms. Except as permitted under the Copyright Act of 1976 and the right to store and retrieve one copy of the work, you may not decompile, disassemble, reverse engineer, reproduce, modify, create derivative works based upon, transmit, distribute, disseminate, sell, publish or sublicense the work or any part of it without McGraw-Hill Education’s prior consent. You may use the work for your own noncommercial and personal use; any other use of the work is strictly prohibited. Your right to use the work may be terminated if you fail to comply with these terms. THE WORK IS PROVIDED “AS IS.” McGRAW-HILL EDUCATION AND ITS LICENSORS MAKE NO GUARANTEES OR WARRANTIES AS TO THE ACCURACY, ADEQUACY OR COMPLETENESS OF OR RESULTS TO BE OBTAINED FROM USING THE WORK, INCLUDING ANY INFORMATION THAT CAN BE ACCESSED THROUGH THE WORK VIA HYPERLINK OR OTHERWISE, AND EXPRESSLY DISCLAIM ANY WARRANTY, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. McGraw-Hill Education and its licensors do not warrant or guarantee that the functions contained in the work will meet your requirements or that its operation will be uninterrupted or error free. Neither McGraw-Hill Education nor its licensors shall be liable to you or anyone else for any inaccuracy, error or omission, regardless of cause, in the work or for any damages resulting therefrom. McGraw-Hill Education has no responsibility for the content of any information accessed through the work. Under no circumstances shall McGraw-Hill Education and/or its licensors be liable for any indirect, incidental, special, punitive, consequential or similar damages that result from the use of or inability to use the work, even if any of them has been advised of the possibility of such damages. This limitation of liability shall apply to any claim or cause whatsoever whether such claim or cause arises in contract, tort or otherwise.

o ony All my love, always

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Reviewers

Gloria A. Albrecht, MS, RT(R) Program Director; School o Diagnostic Imaging Cleveland Clinic Euclid, Ohio

Brenda Grant, RN, MPH, CIC, CHES Manager, In ection Prevention Stam ord Hospital Stam ord, Connecticut

Gail Faig, BS, RT(R)(CV)(CT) Clinical Coordinator School o Radiologic echnology Shore Medical Center Somers Point, New Jersey

Paula R. McPeak, MSRS, RT(R)(M) Program Director Radiologic echnology Riverside College o Health Careers Newport News, Virginia

Jayme A. Frangione, BA, RT(R) Radiologic echnologist Stam ord Hospital Stam ord, Connecticut

Daniel Sorrentino, MS, RT(R) Radiography Program Director Concordia College Bronxville, New York

Merryl N. Fulmer, BS, RT(R)(M)(MR)(QM)(CT) Program Director School o Radiologic echnology Shore Medical Center Somers Point, New Jersey

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Contents

To the Student . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xiii Master Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xxiii 1. Patient Care and Education . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Answers and Explanations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Subspecialty List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 2. Imaging Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Answers and Explanations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 Subspecialty List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 3. Radiation Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125 Answers and Explanations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148 Subspecialty List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176 4. Image Acquisition and Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179 Answers and Explanations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215 Subspecialty List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254 5. Equipment Operation and Quality Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .259 Answers and Explanations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274 Subspecialty List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294 6. Practice Test 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .297 Answers and Explanations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322 Subspecialty List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350 7. Practice Test 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .353 Answers and Explanations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 380 Subspecialty List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 406 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .411

o access your complimentary online practice exam, visit www.MHEAlliedHealth.com.

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To the Student

Your eedback on the previous nine editions o this book has been inspiring and appreciated, and I have enjoyed my correspondence with so many o you. I hope that all who use this book, its companion book PREP: Radiography, companion web site RadReviewEasy. com, and the recent addition o Radiography Flashcards— educators and students alike—will continue to provide eedback in order that these tools may continue to meet their needs. I invite and encourage you to contact me through McGraw-Hill or at [email protected] with comments, questions, and suggestions or uture editions o these learning materials. T e tenth edition o this Q&A contains new and revised material to re ect changes in the American Registry o Radiologic echnologists (ARR ) Content Speci cations published in January 2013 and implemented in January 2014. It includes questions on digital/electronic imaging, including computed and direct digital radiography. Also included is the processing o electronic images including their acquisition, manipulation, and exposure indication. In recognition o the ever increasing importance and application o Computed omography in diagnostic imaging, this edition includes some undamental C questions and explanations. Future edition will address ARR Content Speci cations currently being developed and re ned or implementation in January 2017. You have provided us with a very avorable response to the companion online adaptive question bank: RadReviewEasy. I was very excited about the implementation o this personalized learning tool and your response has con rmed its use ulness. Additionally, RadReviewEasy has given me the enjoyable opportunity to “meet” so many more o you online. RadReviewEasy’s robust per ormance pro le allows users to track their results per ormance by topic and test scores over time and to compare their scores to others

using RadReviewEasy, including test-takers at the users’ speci c institutions. Customization eatures allow Students to: • Choose the length and subject areas o a test or create a set o randomly selected questions. • Retake tests composed o questions previously answered incorrectly so you can ocus on weak areas. • ime your tests or practice at your own pace. • ake tests composed o questions that you are seeing or the rst time. • Create a Personal Study Plan which will support your test preparation and allow you to progress according to your customized study plan. Customization eatures allow Instructors to: • Access the Instructor Reporting ool • rack individual student progress • Generate reports on class activity or subject area per ormance • Generate assignments RadReviewEasy a ords the student an opportunity to practice CB prior to taking the computerized ARR examination. Visit RadReviewEasy.com or in ormation on pricing and subscription terms. I know you realize that review books are not intended to be a “quick x” preparation or the certi cation examination administered by the ARR . It takes at least 2 years o didactic instruction and testing, and hours o clinical practice, to prepare onesel as an entry-level radiographer. During about the last 4 months o radiography education, the actual certi cation examination becomes a rather scary anticipation. Con dent, competent, even cavalier students suddenly become sober when the “the Registry” is mentioned. T ey begin to question all they ever elt con dent about. I you use this book the way it is designed to be

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To the Student

used, and perhaps in conjunction with its companion learning tools: RadReviewEasy.com, the companion book, Radiography PREP (Program Review and Examination Preparation), and the companion Radiography Flashcards, you should be able to set aside any ears you may have. I believe that proper use o the materials presented here, and the above companion tools, will help you overcome your anxieties. First, read the introductory section care ully. It presents proven, sensible suggestions to help improve test-taking per ormance. It elaborates on simple processes to help selection o the correct answer, and several methods and strategies that may be employed while taking “the” test. Probably the most important key to reducing apprehension is to reduce the unknowns to the ewest number. You will also nd an introduction to CB with a description o what to expect, and help ul hints to enhance preparation and reduce anxiety. Second, the ormat and content o the book and the questions on RadReviewEasy have been specially designed to provide ocus and direction or your review, and thus to help you do your very best on your certi cation examination. T e ARR has no secrets and springs no surprises on you. Just as your instructors have made known what is expected o you during your education, the ARR has made known the content, question ormat, and terminology used on the certi cation examination. Every student and educational program has access to the ARR online, where they publish regular updates to keep educators and students current on activities and policies. T e ARR publishes its policies and procedures and several other documents that are use ul to educators and students in preparation or their certi cation examination: Content Speci cations or the Examination in Radiography, Conventions Speci c to the Radiography Examination, and Standard erminology or Positioning and Protection—as well as in ormation on accreditation, ethics review pre-application, certi cation and registration eligibility, advanced placement, brochures, and handbooks. T ese documents are revised periodically and advise educators and students o terminology, categories, content, and approximate weight o content areas on the ARR examination. Although the Content Speci cations by no means serves as a comprehensive radiography curriculum, it does serve as a suitable guide or examination review and preparation. It makes sense to design a review book in which the content, question ormat, and

terminology are similar to that which students can expect to nd on their certi cation examination. T e number o questions ound in each chapter is proportional to the number ound in that category on the actual ARR examination. T e questions are designed to test your problem-solving skills and your ability to integrate acts that t the situation. Most important and practical, I believe, are the detailed explanations ound at the end o each chapter. By themselves, the explanations are good reviews o essential material; they provide a “mini-lecture” or each question. Use them to con rm your correct answers and to better understand your weaker areas. You will see that most explanations will tell you not only why the correct answer is correct, but also why the other answer choices (distractors) are incorrect. Radiography: PREP can be used either be ore this book—as a review o the material this book will test you on—or it can be used with this book to help you strengthen particular essential areas o study. Similarly, the Flashcards and RadReviewEasy can be used or supplemental study and review. Once you have nished reviewing the rst ve chapters, set aside special time or the practice tests in Chapters 6 and 7. ry to simulate the actual examination environment as much as possible. Choose a quiet place ree rom distractions and interruptions, gather the necessary materials, and arrange to be uninterrupted or up to 3 hours. When you’re ready to practice in an exam-simulating digital environment, visit www.MHEAlliedHealth.com to access your ree practice test. In summary, use this book as recommended to help ease your precerti cation examination jitters. Excessive anxiety can impair clear thinking and lower your score. Avoiding excessive stress can improve your concentration and in ormation retrieval process. Remember, you have been well prepared by your program director and instructors, and you have studied and worked hard or at least 2 years. So ollow the advice ound in the Introduction: Prepare yoursel sensibly and keep a positive attitude. I totally agree with a remark the amous automaker Henry Ford once said: “Whether you think you can or whether you think you can’t, you’re right!” I wish you much satis action and success in your radiography career! D. A. Saia

Acknowledgments

Once again, it is a pleasure to recognize and express my sincere appreciation to those who have been so help ul and supportive during the preparation o this tenth edition. Special recognition goes to my ormer coworkers Olive Peart, MS, R (R)(M) and eresa Whiteside, BA, R (R)(BD), (CDB ) or their generous day-to-day support and warm riendship. I am grate ul to all the pro essional sta o McGrawHill. T ere would have never been a tenth edition without their expert direction and support. Special appreciation is expressed to my editor, Catherine A. Johnson—her calm patience during stress ul periods is grate ully appreciated. T ank you also to Midge Haramis, Christina T omas, and Aptara project manager Amit Kashyap. A special note o appreciation goes to Andrew Moyer or his support in the development o Radiography Review Flashcards. Another thank you goes to Jenni er Pollock or her development and maintenance o the books’ companion web site, www.RadReviewEasy.com. Andrew’s and Jenni er’s oresight and expertise have brought success ul added dimensions to both texts—PREP and the Q&A. Everyone at McGraw-Hill has been help ul in the development o these projects; it is always a pleasure to work with their creative and skilled sta . An outstanding group o reviewers was recruited or this edition o Lange Q&A. Gloria Albrecht, Gail Faig, Jayme Frangione, Merryl Fulmer, Brenda Grant, Paula McPeak, and Dan Sorrentino are all invaluable resources to the health care and the radiologic imaging communities. T ey reviewed the manuscript and o ered suggestions to improve style and remove ambiguities and inaccuracies. T eir participation on this project is deeply appreciated. A special thank you is extended to David Sack, BS, R (R), CRA, FAHRA or permission to use several images rom his excellent teaching le.

I wish to express appreciation again to Philips Healthcare, Dunlee Division, and their Inside Sales Manager, Mr. Roger Flees, R. . (Retired), or his assistance in granting permission to reproduce various tube rating charts. T ank you, Roger, or generously sharing your time and expertise! T e support and assistance o ered in previous editions by the late George Spahn o Fuji Medical Systems, USA will always be greatly appreciated. George was instrumental in the introduction and expansion o electronic imaging content in this book and especially in its companion text, PREP: Radiography. George Spahn is a great loss to Fuji Medical Systems, USA and the radiology community, and is missed by so many. Many o the images are reproduced here through the courtesy o Stam ord Hospital, Department o Radiology. A number o images ound in Chapter 4, Image Acquisition and Evaluation, have been reproduced through the courtesy o American College o Radiology. A special thank you is also sent to Conrad P. Ehrlich, MD or images added to this book and to PREP. Appreciative and a ectionate acknowledgment is sent to all my students—past, present, and those still to come. T eir questions, enthusiasm, and desire to learn not only make my job a most pleasant task, but also served as the original stimulus or the preparation o this text. Finally, and most especially, a loving message o appreciation goes to my husband ony. T e preparation and revision o two books and a companion web site and Flashcards is extraordinarily time consuming. His love, understanding, and encouragement (and cooking!) were invaluable and deeply appreciated throughout the preparation o this, and every, edition. D. A. Saia

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Introduction

Completion o the ARR radiography certi cation examination is o en a high point in the career o a radiologic pro essional. Certi cation indicates that the individual has acquired a recognized level o knowledge and expertise and is quali ed to deliver ionizing radiation in the per ormance o medical diagnostic testing. On what does success or ailure depend? Relax! It isn’t as bad as it seems! As the student radiographer nears graduation, there is, understandably, an anxiety that begins to grow. It is a time when you wonder i you are smart enough and i you are skill ul enough. Although there will always be room or growth, these concerns arise rom the realization that an important landmark has been reached. Formal education will soon be at an end—no more written examinations and no more clinical competencies to complete. You will be on your own, proclaimed competent. How will you per orm on the certi cation examination? How will you per orm in the clinical arena? T ese are indeed sobering thoughts. I believe that proper use o the materials presented here will help you overcome your anxieties. You will nd several easy and e ective suggestions or intelligent preparation and test taking. T e suggestions are proven, sensible recommendations to help improve test-taking per ormance. Special ocus has been placed on suggestions or the ARR computer-based testing (CB ) system. T ey elaborate on simple processes to help in selection o the correct answer, and several methods and strategies that may be employed while taking your certi cation examination. Probably the most important key to reducing apprehension is to reduce the unknowns to the ewest number. You will nd that the ormat and content o this review book help ul and specially designed to provide ocus and direction or your review, thus helping you do your very best on the certi cation examination. T e ARR has no secrets and springs no surprises on you. Just as your instructors have made known what is expected o

you during your education, the ARR has made known the content, question ormat, and terminology used on the certi cation examination.

HOW THIS BOOK IS ORGANIZED T ere are three primary sections in this book: a topic-bytopic review with 1,000 examination-type questions and paragraph-length explanations; two 200-question practice tests, also with paragraph-length explanations; and this Introduction, which includes in ormation necessary to help you get the most out o the book and to do your best on the certi cation examination. T is is a current book o practice questions that are designed to mimic actual test questions. In addition, its companion RadReviewEasy.com has additional questions and answers or urther practice in simulated certi cation conditions; visit the site or pricing and subscription terms. In summary, this book will provide you, the student, with a review that will better enable you to simulate and prepare or the certi cation examination by providing an excellent and comprehensive review o radiography.

ABOUT THE EXAMINATION It is essential to care ully read the ARR Radiography Handbook. It describes in detail all the essential testing in ormation required be ore, during, and a er the actual test. Failure to ollow the required steps can result in oreiture o test appointment, and re-application. ARR certi cation examinations are administered at Pearson VUE test centers. o schedule your examination you will need your ARR ID rom the Candidate Status Report. Several types o examinations are administered at

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Introduction

these test centers. I you believe keyboard sounds might distract you, you are encouraged to request earplugs prior to entering the examination room. As noted later in this section, you should plan to arrive at least 15 minutes early. Many test centers require you to be there 30 minutes ahead o the scheduled test time. I you are 15 minutes late, you run the risk o or eiting your appointment time, and being required to reapply. Be prepared to show at least two orms o identi cation, one o which must be government-issued photo ID (e.g., driver’s license, state ID card, passport). Security requirements upon entry at the examination site include a photograph, digital signature, and palm vein scanning. Paper, pencils, etc. are not permitted in the examination room—an erasable board and pen are provided. A calculator is available on the test computer, or you may request a simple our unction calculator rom the test center. I you have any r equest/pr oblem during the test, you should raise your hand or assistance (e.g., screen brightness needs adjustment, other problem with computer, need earplugs, etc.). T ere is a 20-minute tutorial be ore the start o the examination and a 10-minute survey a er completion o the examination. Candidates are presented with multiplechoice questions on a computer screen and directed to select an answer using either the keyboard or a mouse. T e process allows candidates to review or change any answers to any questions prior to submitting the completed examination or scoring. T e tutorial o ered at the beginning o the examination allows the candidate to answer several practice questions. T is ensures that the candidate is thoroughly amiliar with the process. T e national certi cation examination or radiography is a standardized test administered by the ARR and includes 220 multiple-choice questions; 200 questions are scored and 20 questions are unidenti ed pilot questions. T e time allotted or the test is 31⁄2 hours; passing score is 75%. otal time, including tutorial and survey, is 4 hours. Beginning January 2000, the ARR discontinued paper and pencil testing and began to use CB or the administration o its radiography examinations. Pearson VUE testing centers currently administer the ARR examination. T ere is no postmarking deadline or ARR examination applications. Applicants may apply or the examination prior to graduation, but will schedule their examination date within an assigned 90-day window that starts at graduation. Once the ARR application is processed, and the applicant deemed eligible, the ARR sends the candidate their CSR—Candidate Status Report.

T e CSR indicates the candidates ARR number and their examination “window” dates. Most educators advise taking the certi cation examination shortly a er completing all didactic and clinical requirements. o gain admittance to the test center, the candidate must show two current identi cations; at least one must show a photo, and both must show signatures. Positive identi cation will include photograph, digital signature, and palm vein scanning at the test site. A our- unction nonprogrammable calculator is available on the computer, or can be provided to the examinee upon request. est questions are administered in random order, that is, they are not grouped together by subject (and that is the way the two practice tests in this book are designed). Multiple-choice questions are presented on the computer screen and the candidate is directed to select the best answer—the mouse or keyboard may be used. T ere are other types o questions in addition to typical multiple- choice questions. Select-multiple questions require you to select all correct options rom a list o our to eight possible responses. Sorted-list questions require you to place in order a given list o our to eight options. Images with “hot spots” require you to click on a particular spot or region. Videos require that you view a video, then answer the question that ollows. Videos provide you with a control bar that allows to play, pause, and stop. T e candidate is permitted to review or change answers to questions be ore indicating that he/she is nished with the examination.

STRATEGIES FOR STUDYING AND TEST TAKING T e purpose o a test strategy is to make the most o your knowledge, although no strategy, however elaborate, can help you i you do not know your subject. A good test strategy can do the ollowing: 1. Prevent you rom making mistakes 2. Help you to use your time ef ciently 3. Improve your odds o getting the right answer T e single most important trait o a good test strategy is simplicity. T ere are two ways to make and keep a procedure simple: T e rst way is to design it to be simple. T e second is to practice the procedure as it is designed. T e second part is up to you. I you use the ollowing test strategies (particularly the elimination strategy) while using this review book, the strategies will become second nature to you, and you can then concentrate all your attention on passing your certi cation examination.

Introduction

PREPARING FOR THE EXAMINATION Designing a Study Schedule

It is important to establish a routine study schedule. T is schedule should allow you to study at a time when you are at your optimum. Some students are more alert in the morning or this kind o work, while others have better success in the a ernoon. It would not be a good plan to try and study late at night a er a ull day unless this is an optimum time or you. T ere are several advantages to designing a schedule. T e rst is that it orces you to ace the reality o your study load. Many students underplay the amount o time it will take to complete a thorough study, and this can adversely a ect their per ormance. I you write out a schedule that includes both your daily responsibilities and the time you need to study, you will have a sense o the pace needed to complete your review. T e second advantage to designing a schedule is that it will allow you to increase your concentration because the schedule de nes the allotted amount o time or each topic you need to cover. Otherwise, a lot o time can be wasted in determining what to study during each session. Setting up a Study Plan

A er completing the best o radiography programs, even the best o students will have gaps in his or her knowledge, subjects that were somehow missed or orgotten, or that will not come to mind when needed. T ese gaps in your knowledge are o en small; but since one piece o in ormation o en builds upon other pieces, a small gap in your knowledge can sometimes lead to a large drop in your test score. T e best way to get around this problem is to use a well-de ned study plan. Listed below are two alternative plans or you to consider. T e rst is diagnosis and remediation, and the second is SQ3R. Dia gnosis a nd Remedia tion

T is is a two-step approach: diagnosis ( nding out what you do not know) and remediation (learning the material). Diagnosis. Many students graduate rom their programs without a good idea o what they do or do not know. Fortunately, this book has been designed to make diagnosis simple. By ollowing the steps listed below, you will know what you need to learn be ore you take the certi ying examination. Step 1. Begin with Chapter 1, Patient Care, or any o the other rst ve chapters. Go through the questions in

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one sitting, making the experience as similar to the actual examination as possible. Remember to practice test strategies while answering the questions. T is will produce a more valid diagnosis. While taking the test, you should note or highlight words and phrases rom the questions that you do not understand. A er you have nished the questions (but be ore you have graded your work) make a list o the terms you noted and the numbers o the questions that contained them. Step 2. Analyze your results. Read the answers and make a list o the questions you missed. Compare this list with the subspecialty list at the end o the chapter. T is will tell you i you are weak in a particular area. Once you have de ned an area o weakness, pay special attention to the explanations provided. I the answer is still unclear, use the exact page re erences to your textbook or urther study. Anytime you go through your work, picking out and correcting your mistakes, you will gain a greater understanding o your strengths and weaknesses. However, by approaching the analysis systematically, the improvement can be dramatic. Concentrate on your areas o weakness, but be sure to read all the explanations at least once. T is will allow you to compare your reasoning on right and wrong answers and to check or the possibility that you put down the right answer or the wrong reason. Step 3. Repeat the process. T e purpose o this study plan is to get important in ormation into your long-term memory. T e best way to ensure this is to begin your study plan early enough to allow your sel -time to repeat your chapter study one more time be ore the examination. Keep and compare your results rom each review and ocus on any weaknesses still apparent rom the comparison. Remedia tion

Step 1. Read and cross read. Starting with the subspecialty that you missed most o en, make a reading list. For those areas in which you missed three or our questions, a single re erence will probably be enough, but i you missed more than our, you should cross read to cover the same in ormation in more than one text. (You might also want to review these topics in your old class notes.) When you study rom texts, use the index and the table o contents to nd the section you need. I you are using more than one text, compare and look or common ideas. Sometimes, writing a summary o your reading helps to clari y the in ormation. T is technique has been proven to improve retention and understanding, but it can be time consuming.

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Introduction

Step 2. Once you have nished your reading, go back to the questions that you missed. I they still are not clear, consult an expert. Most students are reluctant to approach an instructor with a question that does not relate directly to a class. However, most instructors are glad to answer questions that will improve the chances or their students to obtain a high passing score on the certi cation examination. Instructors appreciate questions that are speci c, well thought out, and which show that the student has done some independent work. SQ3R

T e second method or study is best suited or reviewing your textbooks or urther study once you have identi ed a weakness. It is called the SQ3R and is presented by Frances P. Robinson in his book Ef ective Study. It makes study reading more ef cient and long-term remembering more probable. SQ3R stands or Survey, Question, Read, Recite, and Review. T e steps are as ollows: Survey. First, skim through an entire chapter. 1. T ink about the title o the chapter. What do you already know about the subject? Write ideas in the margins. Read the conclusion. What better way is there to discover the main ideas o a chapter? 2. Read the headings. T ese are the main topics that have been developed by the author. 3. Read the captions under the diagrams, charts, and graphs. Allow approximately 10 to 12 minutes for the survey step. Surveying will help increase your focus and interest in the material.

Learning to use the SQ3R method is a skill that takes practice. O en, students eel that it takes too long and is too complicated, but its use results in an increase in comprehension, interest, and memorization. T e SQ3R method allows you to study at the same time that you are doing your course reading. Summary

Everyone does not have the same learning style, and, as a result, e ective study techniques are not the same or everyone. It is important to choose the method that is best or you, and this will take some experimentation. For instance, some students become rustrated when they cannot comprehend the textbook material while reading when seated at a desk. Sometimes, just getting up and pacing while memorizing can acilitate the learning process i you are having trouble at your desk. Other students learn aster with audio aids. I these are available to you and you are having trouble with learning just rom your books, it may be worth the experiment to see i hearing the material will enhance your learning. Study Groups

While preparing or an examination, properly organizing or attending a study group can be extremely help ul. However, a study group needs to be very ocused with a speci c agenda or each session. Otherwise, it can be a time waster. Listed below are some important points to keep in mind when organizing and conducting a study group:

Recite. At the end o the section, look away rom the book or a ew seconds. Recite and think about what you have just learned. It is best to recite aloud because hearing the in ormation will help increase your memorization.

1. Limit the group size to our or ve people. 2. Select classmates who share your academic goals. 3. Meet the rst time to discuss the meeting times, meeting place, and group goals. 4. Select a group leader and a time keeper. T e group should meet or 2 to 3 hours or each session to ensure a thorough review. 5. Establish an agenda or each meeting that speci es the topics o discussion. T is will save time and lend ocus to the group. It ensures that the group reviews all pertinent topics by slotting time or all areas. 6. Establish group norms that de ne how the group will act. T is would include things such as getting there on time, being prepared, and ending on time. It is important to emphasize that all members must do their air share o the work or the group to gain the maximum bene t.

Review. Reviewing is a key step i you want to retain the material you have read. Reviewing as you study results in less time needed or test preparation.

Study groups are use ul to review and compare both lecture and reading notes, to review textbook in ormation together, and to review examination topics. Group sessions are a

Question. Write out two or three questions relating to each heading. T ese should be questions that you believe will be answered within each section. Use the “who, what, when, where, why, and how” application when generating these questions. Read. Now, read the rst section. Keep in mind the questions you have created and read, with a purpose, as quickly as possible.

Introduction

good time to review the question types used on the certif cation examination, to discuss test-taking strategies, to help each other design study plans, and to drill or review together all material expected to be on the examination. Explain the material to a riend! T is will help you discover what you know and don’t know. T e support o a study group is extremely help ul in building sel -con dence and in overall preparation or examinations. T ey are not intended to replace individual study time, but serve as a supplement. I properly utilized, study groups are an enormous asset or test preparation. Finally, when working within a group, many students are more likely to exert their best e ort because they are accountable to the other members o the group. Practice Tests

T e practice tests (Chapters 6 and 7) can be used in one o the ollowing two ways: (1) as a way o determining strengths and weaknesses be ore you go through the review book or (2) as a nal preparation or the test a er you have done your chapter-by-chapter review. T e practice tests have been designed in an e ort to duplicate the experience o taking the certi cation examination. est questions are administered in random order, questions are not ordered according to topic. T ere ore, the practice test questions in this book are in randomized sequence—just as you will nd questions presented on the ARR certi cation examination. aking the practice tests will make the process more amiliar, so you would not be as nervous when you ace the real test. T e practice test will help you to determine whether or not you are answering the questions quickly enough, and whether your score is high enough to pass. In summary, the practice tests simply give you a chance to practice, giving you an opportunity to practice or the actual examination.

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T at gives you about 57 seconds (0.9 minute) per question. In other words, you have to answer approximately 66 questions per hour. Another way to look at this is by breaking the time into two blocks. I , when you are hal way through the allotted examination time, you have nished a minimum o 110 questions, you are working on time. However, there is one additional complication. Not all questions require equal time to work. It is quite possible to run across a string o dif cult questions early in the test and all behind, and then make up the time with easy questions later in the test. For this reason, being a ew questions short at the hal way mark is not a cause or concern. However, i you have nished signi cantly less than 110 questions a er 90 minutes, you may be starting to all behind. I you do all behind, what can you do to catch up? Sometimes, simply seeing that you are behind and trying to work aster will be enough to motivate you to catch up. I not, you have other options. ry to read through the questions and answers a bit aster. I you have checked only one answer as likely to be right, put that choice down immediately; do not reconsider your answer. Always mark your best choice and move orward. As a rule o thumb, i a act question (one requiring you to recall a act) takes more than a minute or two, select your best answer, “mark” the question (CB has a “mark” button you can click), and go on. You may not skip a question; you must indicate an answer but you may mark the question and return to it later or urther consideration. For a calculation problem (one requiring you to calculate some quantity), give yoursel an extra minute or two. T e computer monitor will indicate the question number you are currently answering, compared to the total number o questions (e.g., number 62 o 220). T e computer counts down rom your allotted time, and the computer screen will indicate the amount o time you have remaining. Elimination: Finding the Correct Answer

TEST-TAKING STRATEGIES Time Management

Keeping track o your time and progress is harder than it might rst appear. Most o us have been surprised while taking a test by how little time was le . T is experience is even more upsetting in the middle o a certi cation examination. Knowing when there is a problem and knowing what to do about it are the objectives o time management. Even with your eye on the clock, calculating the time you have le is not always easy. On the radiography examination, you have 31⁄2 hours to complete 220 questions.

Good test per ormance is sometimes determined by the ability to recognize the incorrect answers as well as the correct ones. Eliminating incorrect answers (termed distractors) not only improves your score, it actually makes the test a more accurate measure o your knowledge. Eliminating a distractor reduces the possible wrong choices. I your knowledge allows you to eliminate two incorrect responses, your odds o a correct response would be increased rom one out o our to one out o two. I you can eliminate three distractors, you would have a 100% probability o getting the right answer. Every distractor you elim inate increases your odds o picking the right answer.

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Introduction

Multiple-choice questions usually have one distractor that is obviously wrong, one distractor that is closer to the correct response, and one distractor that is very close to the correct answer. I you know the subject, you can eliminate the distractors that are most incorrect and improve your chances. I you prepare thoroughly, you will be able to eliminate the others. T e more you know, the better you will do. Many books on test taking suggest complicated systems to eliminate bad answers and rank good ones, but in order to use elimination e ectively, you need a procedure that is both quick and simple. For the ARR CB examination, you must select an answer in order or the next question to be displayed. I you are unsure o your selection, or just want to come back later to review it, you are able to mark the question. All the questions you have marked in this manner will be displayed one by one a er you have completed all 220 questions. T ere is an optional tutorial that you may take prior to starting the examination. aking the tutorial is a good way to become more amiliar with navigating through the examination with greater ease and assurance. Changing Answers

Everyone has had the experience o trying to remember the answer to a question without success and then nding that piece o in ormation urther along in the test. A problem that you stare at or an hour without progress might seem simple i you go on to other problems and come back to it later. Very o en, another question will jog your memory; this technique can work or you during the CB examination. I you are unsure o the correct way to answer a question: 1. I one o the answers seems better than the rest, put it down and mark the question or uture re erence. Come back and check the question at the end i you have time. 2. I you can eliminate two o the possible answers, make an educated guess between the two remaining possibilities. T en, mark the question or uture re erence. 3. Ask yoursel , “Will more time really help me answer this question?” I your answer is no, do the best you can with what you know, using the process o elimination and making an educated guess. Again, mark the question or uture re erence so that you can reread it i there is time at the end. Guessing

You have probably been given a great deal o in ormation and advice about guessing on tests. Most o what you have been told may be con using or contradictory. It may make the problem easier to think in terms o rolling a

die. Imagine a game in which you get a point every time the number 1, or example, comes up. How could you improve your score in this game? One way would be to roll the die as many times as you could. Another way would be to reduce the number o sides on the die so the “right” side would be more likely to come up; this way is called the process o elimination, and it plays a good part in test taking when you are unsure o the correct response. Although we do not suggest guessing as an e ective method o test taking, we do recognize that there will be times when it can be e ective or you. Keep in mind the ollowing things i you need to use this method: 1. T e process o elimination will help you signi icantly in determining the right answer. Use this technique to narrow down the possible choices. 2. Mark the question so that, i you have time, you can come back to it. It is possible that the correct response may reveal itsel through a question urther ahead on the test. 3. Remember that guessing really does not work as an e ective strategy by itsel . You will need to study hard and use guessing in conjunction with other methods or it to be e ective.

PRACTICE TESTS Taking the Practice Test

In order to use the practice test to determine how long the test will take you to complete or how high you will score, you must take it under conditions matching, as closely as possible, the actual test conditions. I you try to eat supper while taking the test, take a 5-hour break in the middle o the test, or stop a er every question to look up the answer, you will not get a clear picture o your current standing or potential to pass the examination. Following are some suggestions on how you can get the most out o the practice test: 1. Keep your schedule completely ree. Find a time and a place that will guarantee that you will not be disturbed or the duration o the test. Most libraries work well or this purpose, as do unoccupied classrooms i you can get access to them. I you have to take the test at home, make sure that you would not be bothered by riends or amily. 2. Minimize your distractions, do not take phone calls, and do not try to watch V or concentrate on anything else other than the test.

Introduction

3. Start at a predetermined time. You may choose to take the practice test at the same time o day your test will be given at the testing center. 4. Bring everything you will need to take the test. T e test center will supply you with scrap paper and a simple nonprogrammable calculator. You must remember to request a calculator rom the testing center personnel during your check-in at the center. 5. Approach the practice tests with the same strategies and attitudes that you plan on using with the actual examination. (Rereading the section on test strategies would be a good idea.) 6. Note time-consuming questions. While taking the test, mark the questions that take longer than 2 or 3 minutes. Do not spend too much time on any one question. 7. Note how ar you get. You should be able to nish the whole practice test in the allotted time, but i you do run out o time, draw a line across the test book to show how ar you got and then nish the rest o the test. Checking Your Results

You should be able to nish all o the questions with enough time le over to go back and check your answers on those problems you marked as dif cult. Your score should be at least 160 correct answers (80%). I you ail at either o these two goals, you need to go over the test careully and try to analyze your problem. wo questions that you can address while analyzing a problem are “Was there a common actor in the questions that gave me trouble?” and “What were the subspecialties o the questions that I missed?” I you keep missing the same type o question, the problem could be easy to x. ry going back and reworking the section o the book that corresponds to that topic. Review your test-taking techniques. Did you spend too much time on a ew questions? Did you spend too much time rereading answers that you had already eliminated as potential answers? I the answer to either o these questions is yes, you might want to review the earlier section on test strategies. TEST STRATEGY CHECKLIST 1. ELIMINATE, CHOOSE, AND MARK Eliminate known incorrect answers, choose the best o the remaining, mark to return to later. 2. DO 50 EVERY45 Try to answer at least 50 questions every 45 minutes. 3. MARK UNCERTAIN ANSWERS Mark questions you guessed on so you can come back and double-check them.

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OPTIMIZING YOUR RESULTS When you take the radiography examination, two actors determine your score: • Your knowledge o the subject • Your per ormance on the examination O the two, knowledge is the key element needed or success. Per ormance is harder to guarantee. For some people, it seems to come naturally. T ese people apply test-taking strategies almost unconsciously, concentrating all their attention on the test. For the rest o the population (which includes most people), standardized tests are some o the most stress ul and unpleasant experiences that they will ever have to ace. Fortunately, it is possible to signi cantly improve your per ormance on tests, even i you have been taking tests all o your li e with no apparent improvement. By mastering the ollowing three areas, you can have better results and greatly reduce the trauma o test taking: 1. Know your test strategies 2. Learn to manage your stress 3. Avoid surprises on the day o the test T e important points or each o these areas are explained in detail in the ollowing sections and are summarized in checklists included at the end o each part o the Introduction. T ese checklists are designed so that you can read them on the day o the test to reassure yoursel that you have not orgotten anything. Test-Taking Strategies

T e strategies recommended earlier serve two purposes: (1) to give you a simple, systematic way o eliminating bad choices and improving your odds o getting a correct response and (2) to help you manage your time most ef ciently during the test. Ma na ging Stress

Over the past 30 or so years, educators have become increasingly concerned about the problems o test anxiety and excessive stress that prevent students rom doing their best on examinations. In the ollowing sections, you will learn some basics about the nature o stress, the di erence between good stress and bad stress, and some management techniques. All o the items listed will be help ul in reducing test anxiety, but the most important point or you to remember is that you are well prepared or the test you are about to take and the odds o your doing well are very good.

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Introduction

Where You Sta nd

T e best way to reduce test anxiety is to address the ollowing points:

strategies you have been practicing, you are experiencing test anxiety. Rela xa tion Techniques

1. 2. 3. 4. 5.

Know the subject Master a test-taking routine Avoid surprises Understand the role o stress in test taking Practice relaxation techniques

The Stress Curve

Recently, stress has received national attention. Magazines discuss it, doctors warn against it, commercials promise to reduce it, and seminars claim to eliminate it. Stress is o en treated as a psychological cancer. T ere is, however, another aspect o stress that receives less attention. In demanding situations requiring optimal per ormance, moderate stress is not only natural, it is actually help ul. T e relationship between stress and per ormance is called the stress curve; the most important aspect o the curve is the location o the maxima. T e maxima is the point o optimal per ormance, which occurs somewhere between too much stress and no stress at all. T ere are plenty o amiliar examples o stress improving per ormance. Athletes o en set personal records during pressure situations such as playo games or international events. Actors give their best per ormances and musicians play or sing best be ore an audience. You can probably think o personal examples as well. Most o us have surprised ourselves at one time or another by doing better than we expected under pressure. How to Recognize Good Stress

I everyone dealt with stress equally well and experienced the same level o stress in the same situation, setting up guidelines or optimal stress levels would be easy. Un ortunately, everyone handles stress di erently, and determining what level o stress is best must be judged on an individual basis. Given the importance o the radiography examination and the amount o time you have spent preparing or it, there is little chance o your stress level being too low when you sit or the test. How do you know i you have too much stress? Feeling nervous does not indicate excessive stress. You are just as likely to eel nervous when you are at your optimal stress level. Stress is excessive when it inter eres with the test-taking process. I you have trouble reading the questions, i you lose your place because you are worrying about the test, or i you are too distracted to ollow the test

Whether or not you anticipate problems with stress, it is a good idea to take a couple o minutes to relax be ore the test. Stretch your muscles, take deep, slow breaths, and try to think about something unrelated to the test. I , during the test, you have trouble working e ectively because o stress, stop, close your eyes, and count to ve while taking some deep, slow breaths. Remind yoursel that you are extremely well prepared or this test. Not many people realize that breathing and anxiety are related, or that a deep-breathing relaxation exercise can be help ul in reducing anxiety. When you eel anxious, you tend to tighten your chest muscles. T is results in breathing changes, with movement predominantly in your upper chest rather than your lower abdomen. Breathing this way o en leads to undesirable conditions: 1. A reduction o oxygen in your blood, which can a ect the way you think and lead to anxiety or atigue. 2. oo much oxygen in your blood, resulting in an uncom ortable condition called hyperventilation. It is important, there ore, to learn how to control your breathing, which, in turn, will result in relaxation. When attempting the ollowing breathing exercise, do not try too hard to relax—it can work against you. Instead, try to be as peace ul as possible. First, take a deep, ull breath and exhale ully and completely. Next, inhale again, mentally counting rom 1 to 4 while breathing in. Hold this breath in while again counting rom 1 to 4. T en, begin ully exhaling, while slowly counting rom 1 to 8. Repeat this sequence our times. I you run out o breath be ore reaching number 8, take deeper breaths and exhale more slowly. I you can learn this technique ahead o time, you can use it while in the examination room without anyone else knowing. I the stress continues, try to think less about what you are doing. A er practicing on 1,400 questions, you have developed a kind o “automatic pilot,” which will allow you to answer questions almost by re ex. O course, this is not the best way to take the test, but i you are aced with serious stress problems, it is an option. Avoiding Surprises The Week Before the Test

You have spent the past 2 to 4 years studying radiography, and the past 2 to 4 months reviewing or this

Introduction

examination. You probably know a great deal more than you think you do. Your top priority now should be getting yoursel up to your best testing per ormance. I you ollow these suggestions, you should have a good start. ake Care o Yoursel . When you take the test, you want to be as healthy and well rested as possible. T e time it takes to get enough sleep, take a walk, or prepare a balanced meal is better spent than hours o last-minute cramming. Cramming is very stress ul! Make sure you are eating healthy; it will improve your energy, help you study better, and help with relaxation. Ca eine might help to energize you but can inter ere with your concentration and make you restless. Excessive ats and carbs make it dif cult to ocus. Snack on berries, oranges, and nuts or a healthy energy and better relaxation. Be certain to make time or physical activity. Exercise improves your mood and stimulates the memory portions o the brain. Yoga and mind ul relaxation can be especially help ul by giving you a break rom study, and helping you eel more energized and ready to get back to work. Reread T is Introduction. T is may be unnecessary advice, but it is worth mentioning. Pay close attention to the gures and checklists. Gather Your Supplies. You want to be sure to get everything you need, but, almost as importantly, you want everything organized so that you can avoid extra e ort and worry. You might want to bring a sweater or light jacket. T is may seem like a strange item, particularly i your test is taken in the summer, but an uncom ortably cold room is extremely distracting, and many public buildings have a wide variation in temperature rom room to room. A sweater or windbreaker is a quick, easy solution. Avoid bringing a large purse or other large bundle. Lockers are available or stowing your personal items not allowed in the examination room, but they are o en airly small lockers and will not accommodate a very large purse or other large package. Scout the Location. It is a very good idea to visit the location o the examination i possible. Getting lost on the morning o a test will add unwanted stress. Keep in mind the ollowing questions: (1) What is the best route to the examination? (2) Where is the parking? (3) Where are the doors to the building? I possible, go into the building and look around.

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reat Yoursel . Go out and do something special. See a movie. Eat out. Go or a drive. Just let yoursel unwind. The Day of the Test

T ere are ew things more irritating than being told not to worry when you eel like worrying, but not worrying is the best thing to do. o help you avoid worrying, two checklists have been included, one physical checklist (things you need to bring) and one mental checklist (things you need to remember). Check o each item and put it out o your mind. Knowing you have both mentally and physically prepared will help you to relax be ore the examination. You should plan to arrive a ew minutes early. Many test centers require you to be there 30 minutes ahead o the scheduled test time. You will probably want to eat a light meal be ore taking the test. Digestion tends to slow down when a person is under stress, so a large meal is, in most cases, a bad idea. You will also want to avoid excessive stimulants (and ca eine is de nitely considered a stimulant). T is brings up another point. Although you want to be well rested and alert, you should be care ul not to disrupt your normal routine any more than necessary. Getting extra rest, eating light, and avoiding stimulants are relative suggestions—relative to your habits and li estyle. Do not make drastic changes on the day o the test. Get an extra hal hour or hour o sleep. Eat a lighter meal than you usually would. I you drink co ee, drink a little less than normal. When you get to the testing center, take a ew minutes to relax. Walk around. Stretch your muscles. Remind yoursel that you have put a great deal o work into doing well on this test and that work is the main actor or determining success. PHYSICAL CHECKLIST (What to Bring) 1. Your admission ticket 2. Two current IDs 3. Sweater or windbreaker

MENTAL CHECKLIST 1. 2. 3. 4. 5.

Remind yoursel that you are well prepared Take the computer tutorial Use your test-taking strategies Focus on the test, not on the surroundings A ter you have f nished, use the same strategies to go over any questions you marked or review

xxii

Introduction

REFERENCES Benson H, Klipper M. T e Relaxation Response. New York: Avon Books; 1990. Bosworth S, Brisk M. Learning Skills or the Science Student. FL: H&H Publishing Company; 1986. Co man S. How to Survive at College. IN: College own Press; 1988. Hamachek A. Coping in College: A Guide or Academic Success. Boston, MA: Allyn and Bacon; 1994.

Krantz H, Kemmelman J. Keys to Reading and Study Skills. New York: Holt, Rinehart & Winston; 1985. Palav S. Learning Strategies or Allied Health Students. Philadelphia, PA: WB Saunders; 1995. Robinson F. Ef ective Study. New York: Harper and Row; 1970. Saia DA. Radiography Program Review Exam Preparation. 8th ed. New York: McGraw-Hill; 2006. Vitale B, Nugent P. est Success: est- aking echniques or the Health Care Student. Philadelphia, PA: FA Davis; 2015.

Master Bibliography

On the last line o each answer/explanation, there appears the last name o the author or editor o one o the publications listed here, along with a number or numbers indicating the correct page or range o pages where in ormation relating to the correct answer may be ound. For example, (Bushong, p. 45) re ers to page 45 o Bushong’s Radiologic Science or echnologists. Adler AM, Carlton RR. Introduction to Radiologic Sciences and Patient Care. 5th ed. St. Louis, MO: Saunders Elsevier; 2012. ARR . New est Item Format or Radiography Examination. https://www.arrt.org/pd s/Exainations/itemFormats.pd . Accessed March 20, 2015. ASR Code o Ethics. https://www.asrt.org/docs/ practicestandards/codeo ethics.pd BEIR Report VII. http://dels.nas.edu/dels/rpt_brie s/ beir_vii_ nal.pd Bontrager KL, Lampignano JP. extbook o Radiographic Positioning and Related Anatomy. 7th ed. St Louis, MO: Mosby; 2010. Bontrager KL, Lampignano JP. extbook o Radiographic Positioning and Related Anatomy. 8th ed. St Louis, MO: Mosby; 2014. Bushong SC. Radiologic Science or echnologists. 9th ed. St. Louis, MO: Mosby; 2008. Bushong SC. Radiologic Science or echnologists. 10th ed. St. Louis, MO: Mosby; 2013. Carlton RR, Adler AM. Principles o Radiographic Imaging. 5th ed. Albany, NY: Delmar; 2013. Carter C, Vealé B. Digital Radiography and PACS. 1st ed revised. Mosby Elsevier; 2010. Chen MYM, Pope L, Ott DJ. Basic Radiology. 1st ed. McGraw-Hill; 2004. Dowd SB, ilson ER. Practical Radiation Protection and Applied Radiobiology. 2nd ed. Philadelphia, PA: WB Saunders; 1999.

Dutton AG, Linn-Watson A, orres LS. orres’ Patient Care in Imaging echnology. 8th ed. Philadelphia, PA: Lippincott; 2013. Ehrlich RA, Coakes DM. Patient Care in Radiography. 8th ed. St. Louis, MO: Mosby; 2013. Fosbinder R, Orth D. Essentials o Radiologic Science. Baltimore, MD: Lippincott Williams & Wilkins; 2012. Fosbinder RA, Kelsey CA. Essentials o Radiologic Science. 1st ed. New York: McGraw-Hill; 2002. Frank ED, Long BW, Smith BJ. Merrill’s Atlas o Radiographic Positioning and Procedures. Vols 1, 2, and 3. 12th ed. St. Louis, MO: Mosby; 2012. Fuji Photo Film Co., Ltd (FCR) Fuji Computed Radiography, Minato-Ku, Japan, 2002. McConnell H. T e Nature o Disease, Pathology or the Health Pro essions. 2nd ed. Wolters Kluwer Lippincott Williams & Wilkins; 2014. Mills WR. T e relation o bodily habitus to visceral orm, tonus, and motility. Am J Roentgenol 1917;4: 155–169. NCRP Report No 116. Recommendations on Limits or Exposure to Ionizing Radiation. NCRP; 1987. NCRP Report No 99. Quality Assurance or Diagnostic Imaging. NCRP, 1990. NCRP Report No 160. Ionizing Radiation Exposure o the Population o the United States. NCRP, 2009. Peart O. Mammography and Breast Imaging PREP. New York: McGraw-Hill; 2012. Peart O. Lange Radiographic Positioning Flashcards. New York: McGraw-Hill; 2014. Saia DA. Radiography PREP. 7th ed. New York: McGrawHill; 2012. Saia DA. Radiography PREP. 8th ed. New York: McGrawHill; 2015. Saladin KS Anatomy and Physiology: T e Unity o Form and Function. 7th ed. New York: McGraw-Hill; 2015. Seeram E. Digital Radiography: An Introduction. Delmar: CENGAGE Learning, 2011.

xxiii

xxiv

Master Bibliography

Selman J. T e Fundamentals o Imaging Physics and Radiobiology. 9th ed. Spring eld, IL: Charles C T omas; 2000. Shephard C . Radiographic Image Production and Manipulation. 1st ed. New York: McGraw-Hill; 2003. Statkiewicz-Sherer MA, Visconti PJ, Ritenour ER. Radiation Protection in Medical Radiography. 6th ed. St. Louis, MO: Mosby; 2011. Statkiewicz-Sherer MA, Visconti PJ, Ritenour ER, Haynes KW. Radiation Protection in Medical Radiography. 7th ed. St. Louis, MO: Mosby; 2014.

T omas CL, ed. aber’s Cyclopedic Medical Dictionary. 20th ed. Philadelphia, PA: F A Davis; 2005. ortora GJ, Derrickson B. Principles o Anatomy and Physiology. 12th ed. Hoboken, NJ: John Wiley & Sons, Inc; 2009. Wolbarst AB. Physics o Radiology. Stam ord, C : Appleton & Lange; 2003. Wolbarst AB. Physics o Radiology. 2nd ed. Madison, WI: Medical Physics Publishing; 2005.

CHAPTER 1

Patient Care and Education Questions

DIRECTIONS (Questions 1 through 130): Each of the numbered items or incomplete statements in this section is followed by answers or by completions of the statement. Select the one lettered answer or completion that is best in each case. 1. Which blood vessels are best suited or determination o pulse rate? (A) (B) (C) (D)

Super cial arteries Deep arteries Super cial veins Deep veins

2. Diseases that require contact precautions include 1. MRSA 2. Clostridium di cile (C-di ) 3. B (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

3. Circumstances that could prevent a radiography student rom meeting ARR certi cation requirements include 1. ailing one or more courses in the radiography program 2. being suspended rom a radiography program 3. being dismissed/expelled rom a radiography program (A) (B) (C) (D)

4. For medicolegal reasons, radiographic images are required to include all the ollowing in ormation except (A) (B) (C) (D)

the patient’s name and/or identi cation number the patient’s birth date a right- or le -side marker the date o the examination

5. A radiographer who discloses con dential patient in ormation to unauthorized individuals can be ound guilty o (A) (B) (C) (D)

libel invasion o privacy slander de amation

6. An iatrogenic in ection is one caused by (A) (B) (C) (D)

physician intervention blood-borne pathogens chemotherapy in ected droplets

7. A vasomotor e ect experienced a er injection o a contrast agent is characterized by all o the ollowing symptoms except (A) (B) (C) (D)

nausea syncope hypotension anxiety

1 only 1 and 2 only 2 and 3 only 1, 2, and 3 1

2

1: Patient Care and Education

8. Which o the below is the rst step to be taken in the per ormance o a radiographic examination? (A) (B) (C) (D)

Obtain clinical history Provide appropriate patient assistance Veri y patient identity Use appropriate in ection control

9. Which o the ollowing drugs is used to treat dysrhythmias? (A) (B) (C) (D)

Epinephrine Lidocaine Nitroglycerin Verapamil

10. Examples o a portal o entry in the cycle o in ection include 1. a break in the skin 2. nasal mucous membrane 3. urinary tract (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

11. Administration o contrast agents or radiographic demonstration o the spinal canal is per ormed by which o the ollowing parenteral routes? (A) (B) (C) (D)

Subcutaneous Intravenous Intramuscular Intrathecal

12. T e radiographer can help to alleviate patient anxiety in the ollowing way(s) 1. care ul explanation o the procedure 2. avoiding use o complex medical terms 3. listening care ully to the patient (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

13. Which o the ollowing can be transmitted via in ected blood? 1. HBV 2. AIDS 3. B (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

14. T e mechanical device used to correct an ine ectual cardiac rhythm is a (A) (B) (C) (D)

de brillator cardiac monitor crash cart resuscitation bag

15. A small container holding several doses o medication is termed (A) (B) (C) (D)

an ampoule a vial a bolus a cara e

16. You have encountered a person who is apparently unconscious and unresponsive. T ere is no rise and all o the chest, and you can hear no breath sounds. You should rst (A) begin mouth-to-mouth rescue breathing, giving two ull breaths (B) proceed with the Heimlich maneuver (C) begin with 30 external chest compressions at a rate o 100 compressions/min (D) begin with 5 external chest compressions at a rate o 50 compressions/min 17. In classi ying IV contrast agents, the total number o dissolved particles in solution per kilogram o water de nes (A) (B) (C) (D)

osmolality toxicity viscosity miscibility

Questions: 8–27

18. A patient who is warm, ushed, or everish is said to be (A) (B) (C) (D)

diaphoretic ebrile cyanotic anxious

19. Misunderstandings between cultures can happen as a result o 1. looking directly into someone’s eyes 2. the use o certain gestures 3. standing too close while speaking to another (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

20. T e legal doctrine res ipsa loquitur means which o the ollowing? (A) (B) (C) (D)

A matter settled by precedent A thing or matter settled by justice T e thing speaks or itsel Let the master answer

21. Some proteins in latex can produce mild-to-severe allergic reactions. Medical equipment that could contain latex includes 1. airways 2. enema tips 3. catheters (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

22. T e request or imaging services or hospital patients generally includes the ollowing in ormation 1. patient name and/or identi cation number 2. mode o travel to Imaging department 3. name o re erring physician (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

3

23. A large volume o medication introduced intravenously over a period o time is termed (A) (B) (C) (D)

an IV push an in usion a bolus a hypodermic

24. T e legal document or individual authorized to make an individual’s healthcare decisions, should the individual be unable to make them or himsel or hersel , is the 1. advance healthcare directive 2. living will 3. healthcare proxy (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

25. An inanimate object that has been in contact with an in ectious microorganism is termed a (A) (B) (C) (D)

vector omite host reservoir

26. In which stage o in ection do the in ective microbes begin to multiply? (A) (B) (C) (D)

Latent period Incubation period Disease phase Convalescent phase

27. A partially obstructed airway is clinically maniested in the ollowing way(s) 1. dysphasia 2. noisy, labored breathing 3. nailbed and lip cyanosis (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

4

1: Patient Care and Education

28. All the ollowing statements regarding hand hygiene and skin care are correct, except (A) hands should be cleansed be ore and a er each patient examination (B) aucets should be opened and closed with paper towels (C) hands should be smooth and ree rom chapping (D) any cracks or abrasions should be le uncovered to acilitate healing 29. All o the ollowing are correct concepts o good body mechanics during patient li ing/moving, except (A) the radiographer should stand with eet approximately 12 inches apart and with one oot slightly orward (B) the body’s center o gravity should be positioned over its base o support (C) the back should be kept straight; avoid twisting (D) when carrying a heavy object, hold it away rom the body 30. When a patient arrives in the radiology department with a urinary Foley catheter bag, it is important to (A) place the drainage bag above the level o the bladder (B) place the drainage bag at the same level as the bladder (C) place the drainage bag below the level o the bladder (D) clamp the Foley catheter 31. When a patient having one strong side and one weak side is being assisted onto an x-ray table, the radiographer should (A) (B) (C) (D)

start with the weaker side closer to the table start with the stronger side closer to the table always use a two-person li li the patient care ully onto the table

32. Possible side e ects o an iodinated contrast medium that is administered intravenously include all the ollowing except 1. a warm, ushed eeling 2. altered taste 3. rash and hives (A) (B) (C) (D)

1 only 3 only 2 and 3 only 1, 2, and 3

33. In the blood pressure reading 145/75 mm Hg, what does 75 represent? 1. T e phase o relaxation o the cardiac muscle tissue 2. T e phase o contraction o the cardiac muscle tissue 3. A higher-than-average diastolic pressure (A) (B) (C) (D)

1 only 2 only 1 and 3 only 2 and 3 only

34. Facsimile transmission o health in ormation is 1. not permitted 2. permitted or urgently needed patient care 3. permitted or third-party payer hospitalization certi cation (A) (B) (C) (D)

1 only 2 only 2 and 3 only 1, 2, and 3

35. Forms o intentional misconduct include 1. slander 2. invasion o privacy 3. negligence (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

Questions: 28–45

36. Which o the ollowing statements is correct with regard to assisting a patient rom a wheelchair to an x-ray table? (A) T e wheelchair should be parallel with the x-ray table (B) T e wheelchair should be 45 degrees to the x-ray table (C) T e wheelchair should directly ace the x-ray table (D) T e wheelchair ootrests should be olded down or oot support during trans er 37. In her studies on death and dying, Dr. Elizabeth Kubler-Ross described the rst stage o the grieving process as (A) (B) (C) (D)

denial anger bargaining depression

38. You and a ellow radiographer have received an unconscious patient rom a motor vehicle accident. As you per orm the examination, it is important that you 1. re er to the patient by name 2. make only those statements that you would make with a conscious patient 3. reassure the patient about what you are doing (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

39. A cathartic is used to (A) (B) (C) (D)

inhibit coughing promote elimination o urine stimulate de ecation induce vomiting

40. Another term used to describe nosocomial in ections is (A) (B) (C) (D)

iatrogenic healthcare-associated in ections droplet airborne

5

41. What is the needle angle usually recommended or intravenous injections? (A) (B) (C) (D)

90 degrees 75 degrees 45 degrees 15 degrees

42. T e belie that one’s own cultural ways are superior to any other is termed (A) (B) (C) (D)

ethnology ethnobiology ethnocentrism ethnography

43. Potential violations o HIPAA standards include the ollowing 1. protected healthcare in ormation is accessible to hospital employees only 2. a copy o authorization or release o medical in ormation is kept on le 3. patient in ormation computer les must be encrypted (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

44. Which o the ollowing may be used to e ectively reduce the viscosity o contrast media? (A) (B) (C) (D)

Warming Re rigeration Storage at normal room temperature Storage in a cool, dry place

45. T e type o shock o en associated with pulmonary embolism or myocardial in arction is classi ed as (A) (B) (C) (D)

neurogenic cardiogenic hypovolemic septic

6

1: Patient Care and Education

46. Which o the ollowing must be included in a patient’s medical record or chart? 1. Diagnostic and therapeutic orders 2. Medical history 3. In ormed consent (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

47. What type o precautions prevent the spread o in ectious agents in droplet orm? (A) (B) (C) (D)

51. Which o the ollowing legal phrases de nes a circumstance in which both the healthcare provider’s and the patient’s actions contributed to an injurious outcome? (A) (B) (C) (D)

52. What is the rst treatment or extravasation o contrast media during an IV injection? (A) Apply a hot compress (B) Apply a cold compress (C) Apply pressure to the vein until bleeding stops (D) Remove the needle and locate a sturdier vein immediately

Contact precautions Airborne precautions Protective isolation Strict isolation

48. Which o the ollowing conditions must be met in order or patient consent to be valid?

53. Which o the ollowing diastolic pressure readings might indicate hypertension?

1. T e patient must sign the consent orm be ore receiving sedation 2. T e physician named on the consent orm must per orm the procedure 3. Blank spaces on the orm must be completed by the physician a er patient signature (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

49. Examples o nonverbal communication include 1. Appearance 2. Eye contact 3. ouch (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

50. Each o the ollowing is an example o a omite except (A) (B) (C) (D)

a doorknob a tick a spoon an x-ray table

Intentional misconduct Contributory negligence Gross negligence None o the above

(A) (B) (C) (D) 54.

40 mm Hg 60 mm Hg 80 mm Hg 100 mm Hg

o reduce the back strain that can result rom moving heavy objects, the radiographer should (A) hold the object away rom his or her body when li ing (B) bend at the waist and pull (C) pull the object (D) push the object

55. All the ollowing statements regarding oxygen delivery are true except (A) oxygen is classi ed as a drug and must be prescribed by a physician (B) the rate o delivery and mode o delivery must be part o a physician order or oxygen (C) oxygen may be ordered continuously or as needed by the patient (D) none o the above; they are all true

Questions: 46–63

56. I an emergency trauma patient experiences hemorrhaging rom a leg injury, the radiographer should 1. apply pressure to the bleeding site 2. call the emergency department or assistance 3. apply a pressure bandage and complete the examination (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

57. Gas-producing powder or crystals usually are ingested preliminary to which o the ollowing examinations? (A) (B) (C) (D)

Double-contrast barium enema (BE) Double-contrast gastrointestinal (GI) series Oral cholecystogram IV urogram (IVU)

58. According to the CDC, all the ollowing precaution guidelines are true except (A) airborne precautions require that the patient wear a mask (B) masks are indicated when caring or patients on MRSA precautions (C) patients under MRSA precautions require a negative-pressure room (D) masks are indicated when caring or a patient on droplet precautions 59. Routes o drug administration include 1. sublingual 2. topical 3. parenteral (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

7

60. You are working in the outpatient department and receive a patient who is complaining o pain in the right hip joint; however, the requisition asks or a le emur examination. What should you do? (A) Per orm a right hip examination (B) Per orm a le emur examination (C) Per orm both a right hip and a le emur examination (D) Check with the re erring physician 61. While per orming mobile radiography on a patient, you note that the requisition is or a chest image to check placement o a Swan–Ganz catheter. A Swan–Ganz catheter is a(n) (A) (B) (C) (D)

pacemaker chest tube IV catheter urinary catheter

62. Which o the ollowing diagnostic examinations require(s) restriction o a patient’s diet? 1. Barium enema 2. Pyelogram 3. Metastatic survey (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 2 and 3 only

63. T e radiographer must per orm which o the ollowing procedures prior to entering a contact isolation room with a mobile x-ray unit? 1. Put on gown and gloves only. 2. Put on gown, gloves, mask, and cap. 3. Clean the mobile x-ray unit. (A) (B) (C) (D)

1 only 2 only 1 and 3 only 2 and 3 only

8

1: Patient Care and Education

64. Examples o nasogastric (NG) tubes include 1. Swan—Ganz 2. Salem-sump 3. Levin (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

65. All the ollowing are central venous lines except (A) (B) (C) (D)

a Port-a-Cath a PICC a Swan–Ganz catheter a Salem-sump

66. T e most e ective method o sterilization is (A) (B) (C) (D)

dry heat moist heat pasteurization reezing

67. T e condition in which pulmonary alveoli lose their elasticity and become permanently in ated, causing the patient to consciously exhale, is (A) bronchial asthma (B) bronchitis (C) emphysema (D) B 68. Nosocomial in ections are those acquired rom (A) (B) (C) (D)

healthcare acilities physicians inanimate objects insects

69. What venous device can be used or a patient requiring IV injections at requent or regular intervals? (A) (B) (C) (D)

Butter y needle Intermittent injection port IV in usion Hypodermic needle

70. All o the ollowing statements regarding in ormed consent are true, except (A) in ormed consent is required or research participation (B) the physician named on the consent orm must per orm the procedure (C) the consent orm cannot be revoked, once signed (D) A parent or legal guardian is required to sign or a minor 71. In which o the ollowing situations should a radiographer wear protective eye gear (goggles)? 1. When per orming an upper GI radiographic examination 2. When assisting the radiologist during an angiogram 3. When assisting the radiologist in a biopsy/ aspiration procedure (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

72. In reviewing a patient’s blood chemistry, which o the ollowing blood urea nitrogen (BUN) ranges is considered normal? (A) (B) (C) (D)

0.6 to 1.5 mg/dL 4.5 to 6 mg/dL 8 to 25 mg/dL Up to 50 mg/dL

73. Procedures requiring intravascular iodinated contrast agent or patients being treated with metormin or type 2 diabetes, should receive the ollowing instructions (A) discontinue at time o or prior to examination and withhold 48 hours ollowing examination (B) discontinue 48 hours prior to examination and resume ollowing examination (C) discontinue at time o or prior to examination and resume ollowing examination (D) discontinue at time o or prior to examination and withhold 4 hours ollowing examination

Questions: 64–81

74. All the ollowing are orms o mechanical obstruction seen in neonates or in ants except (A) (B) (C) (D)

paralytic ileus meconium ileus volvulus intussusception

75. T e pain experienced by an individual whose coronary arteries are not conveying suf cient blood to the heart is called (A) (B) (C) (D)

tachycardia bradycardia angina pectoris syncope

76. An MRI procedure is contraindicated or a patient who has (A) (B) (C) (D)

a herniated disk cochlear implant dental llings subdural bleeding

77. T e advantages o using nonionic, water-soluble contrast media include 1. cost-containment bene ts 2. low toxicity 3. ewer adverse reactions (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

78. A radiographer should recognize that gerontologic patients o en have undergone physical changes that include loss o 1. muscle mass 2. bone calcium 3. mental alertness (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

9

79. Which o the ollowing statements is (are) true regarding a two-member team per orming mobile radiography on a patient with MRSA precautions? 1. One radiographer remains “clean”—that is, he or she has no physical contact with the patient 2. T e radiographer who positions the mobile unit also makes the exposure 3. T e radiographer who positions the cassette also retrieves the cassette and removes it rom its plastic protective cover (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

80. Symptoms associated with a respiratory reaction to contrast media include 1. sneezing 2. hoarseness 3. wheezing (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

81. While in your care or a radiologic procedure, a patient asks to see his medical record/chart. Which o the ollowing is the appropriate response? (A) In orm the patient that the records are or healthcare providers to view, not or the patient (B) In orm the patient that you do not know how to access his records (C) In orm the patient that he has the right to see his records but he should request to view them with his physician so that they are interpreted properly (D) Show the patient his records and leave him alone or a ew minutes to review them

10

1: Patient Care and Education

82. Skin discoloration owing to cyanosis may be observed in the 1. gums 2. earlobes 3. tongue (A) (B) (C) (D)

1 only 1 and 2 only 3 only 1, 2, and 3

83. Diseases spread by direct or close contact include 1. MRSA 2. Conjunctivitis 3. Rotavirus (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

84. You receive an ambulatory patient or a GI series. As the patient is being seated on the x-ray table, he tells you he eels aint. You should 1. lay the patient down on the x-ray table 2. elevate the patient’s legs or place the table slightly rendelenburg 3. leave quickly and call or help (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

85. T e medical term or hives is (A) (B) (C) (D)

vertigo epistaxis urticaria aura

86. Blood pressure is measured in units o (A) (B) (C) (D)

millimeters o mercury (mm Hg) beats per minute degrees Fahrenheit (°F) liters per minute (L/min)

87. Which ethical principle is related to sincerity and truth ulness? (A) (B) (C) (D)

Bene cence Autonomy Veracity Fidelity

88. T e medical term or congenital club oot is (A) (B) (C) (D)

coxa plana osteochondritis talipes muscular dystrophy

89. In what order should the ollowing examinations be per ormed? 1. Upper GI series 2. IVU 3. BE (A) (B) (C) (D)

3, 1, 2 1, 3, 2 2, 1, 3 2, 3, 1

90. Hypochlorite bleach (Clorox) and Lysol are examples o (A) (B) (C) (D)

antiseptics bacteriostatics anti ungal agents disin ectants

91. T e condition that allows blood to shunt between the right and le ventricles is called (A) (B) (C) (D)

patent ductus arteriosus coarctation o the aorta atrial septal de ect ventricular septal de ect

92. Logrolling is a method o moving patients having suspected (A) (B) (C) (D)

head injury spinal injury bowel obstruction extremity racture

Questions: 82–101

93. T e cycle o in ection includes which o the ollowing components? 1. Reservoir o in ection 2. Susceptible host 3. Mode o transmission (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

94. T e act o inspiration will cause elevation o the 1. sternum 2. ribs 3. diaphragm (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

95. A radiologic technologist can be ound guilty o a tort in which o the ollowing situations? 1. Failure to shield a patient o childbearing age rom unnecessary radiation 2. Imaging the wrong patient 3. Using patient immobilization against their will (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

96. Guidelines or cleaning contaminated objects or sur aces include which o the ollowing? 1. Clean rom the least contaminated to the most contaminated areas. 2. Clean in a circular motion, starting rom the center and working outward. 3. Clean rom the top down. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

11

97. I a radiographer per ormed a lumbar spine examination on a patient who was supposed to have an elbow examination, which o the ollowing charges may be brought against the radiographer? (A) (B) (C) (D) 98.

Assault Battery False imprisonment De amation

ypes o in ammatory bowel disease include 1. ulcerative colitis 2. Crohn’s disease 3. intussusception (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

99. Which o the ollowing statements regarding tracheostomy patients is true? 1. racheostomy patients have dif culty speaking. 2. Mobile chest imaging requires any tracheostomy tube to be rotated out o view. 3. Audible rattling sounds indicate a need or suction. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

100. When caring or a patient with an IV line, the radiographer should keep the medication (A) (B) (C) (D)

18 to 20 inches above the level o 18 to 20 inches below the level o 28 to 30 inches above the level o 28 to 30 inches below the level o

the vein the vein the vein the vein

101. Diseases that require droplet precautions include 1. rubella 2. mumps 3. in uenza (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

12

1: Patient Care and Education

102. A Protective Environment or Neutropenic Precautions (sometimes re erred to as expanded precautions) as indicated is required in which o the ollowing conditions? 1. B 2. Burns 3. Leukemia (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

103. When a GI series has been requested on a patient with a suspected per orated ulcer, the type o contrast medium that should be used is (A) (B) (C) (D)

a thin barium sul ate suspension a thick barium sul ate suspension water-soluble iodinated media oil-based iodinated media

104. Nitroglycerin is used (A) (B) (C) (D)

to relieve pain rom angina pectoris to prevent a heart attack as a vasoconstrictor to increase blood pressure

105. A patient experiencing an episode o syncope should be placed in which o the ollowing positions? (A) (B) (C) (D)

Dorsal recumbent with head elevated Dorsal recumbent with eet elevated Lateral recumbent Seated with eet supported

106. T e diameter o a needle’s lumen is re erred to as its (A) (B) (C) (D)

bevel gauge hub length

107. Anaphylactic shock mani ests early symptoms that include 1. dysphagia 2. itching o palms and soles 3. constriction o the throat (A) (B) (C) (D)

1 only 2 only 2 and 3 only 1, 2, and 3

108. A patient in a recumbent position with the head higher than the eet is said to be in which o the ollowing positions? (A) rendelenburg (B) Fowler (C) Sims (D) Stenver 109. T e normal average rate o respiration or a healthy adult patient is (A) (B) (C) (D)

5 to 7 breaths/min 8 to 12 breaths/min 12 to 20 breaths/min 20 to 30 breaths/min

110. Which o the ollowing is a vasopressor and may be used or an anaphylactic reaction or a cardiac arrest? (A) (B) (C) (D)

Nitroglycerin Epinephrine Hydrocortisone Digitoxin

111. Examples o means by which in ectious microorganisms can be transmitted via indirect contact include 1. a omite 2. a vector 3. nasal or oral secretions (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Questions: 102–120

112. All the ollowing rules regarding proper hand washing technique are correct except (A) (B) (C) (D)

keep hands and orearms lower than elbows use paper towels to turn water on avoid using hand lotions whenever possible care ully wash all sur aces and between ngers

113. T e ollowing instructions should be given to a patient ollowing a barium sul ate contrast examination 1. increase uid and ber intake or several days 2. changes in stool color will occur until all barium has been evacuated 3. contact a physician i no bowel movement occurs in 24 hours (A) (B) (C) (D)

1 only 2 only 1 and 3 only 1, 2, and 3

114. Instruments required to assess vital signs include 1. a stethoscope 2. a sphygmomanometer 3. a watch with a second hand (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

115. T e medical abbreviation meaning “a er meals” is (A) (B) (C) (D)

tid qid qh pc

116. Symptoms o inadequate oxygen supply include 1. dyspnea 2. cyanosis 3. retraction o intercostal spaces (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

13

117. Examples o various diverse cultural groups include the ollowing 1. Generational groups 2. Socioeconomic groups 3. Handicapped groups (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

118. In which o the ollowing conditions is a doublecontrast BE essential or demonstration o the condition? 1. Polyps 2. Colitis 3. Diverticulosis (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

119. When a radiographer is obtaining a patient history, both subjective and objective data should be obtained. An example o subjective data is that (A) the patient appears to have a productive cough (B) the patient has a blood pressure o 130/95 mm Hg (C) the patient states that she experiences extreme pain in the upright position (D) the patient has a palpable mass in the right upper quadrant o the le breast 120. All o the ollowing are use ul resources or non– English-speaking patients, except (A) (B) (C) (D)

Automated language lines Special dual headset phones A certi ed interpreter A amily member or riend

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1: Patient Care and Education

121. Which o the ollowing is (are) symptom(s) o shock? 1. Pallor and weakness 2. Increased pulse 3. Fever (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

126. When reviewing patient blood chemistry levels, what is considered the normal creatinine range? (A) (B) (C) (D)

127. Which o the ollowing medical equipment is used to determine blood pressure?

122. Increased pain threshold, breakdown o skin, and atrophy o at pads and sweat glands are all important considerations when working with which o the ollowing groups o patients? (A) (B) (C) (D)

(A) (B) (C) (D)

1. Pulse oximeter 2. Stethoscope 3. Sphygmomanometer (A) (B) (C) (D)

In ants Children Adolescents Geriatric patients

123. T e practice that is used to retard the growth o pathogenic bacteria is termed

1. B 2. mumps 3. rubella (A) (B) (C) (D)

124. T e usual patient preparation or an upper GI examination is

125. Success ul, e ective communication includes prociency in the ollowing skills 1. Writing 2. Speech 3. Observation (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

128. Diseases whose mode o transmission is through the air include

antisepsis disin ection sterilization medical asepsis

(A) nothing by mouth (NPO) 8 hours be ore the examination (B) light break ast only on the morning o the examination (C) clear uids only on the morning o the examination (D) 2 oz o castor oil and enemas until clear

0.6 to 1.5 mg/dL 4.5 to 6 mg/dL 8 to 25 mg/dL Up to 50 mg/dL

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

129. In pediatric imaging, a neonate is usually describes (A) Preschooler (B) oddler (C) In ant (D) Newborn 130.

racheostomy is indicated in cases o tracheal obstruction when the obstruction is located (A) (B) (C) (D)

below the level o the larynx above the level o the larynx in erior to the carina in the right primary bronchus

Answers and Explanations

1. (A) Super cial arteries are best suited or determination o pulse rate. T e ve most easily palpated pulse points are the radial, carotid, temporal, emoral, and popliteal pulses. T e radial pulse is used most requently. T e apical pulse, at the apex o the heart, is most accurate and can be determined with the use o a stethoscope. 2. (B) Any disease spread by direct or close contact, such as MRSA and Clostridium di cile (C-di ), and some wounds require contact precautions. Contact precaution procedures require a private patient room and the use o gloves and gowns or anyone coming in direct contact with the in ected individual or the in ected person’s environment. Some acilities require healthcare workers to also wear a mask when caring or a patient with MRSA in ection. 3. (C) T e word honor implies regard or the standards o one’s pro ession, a re usal to lie/deceive, an uprightness o character or action, a trustworthiness and incorruptibility. Other words used to describe these qualities are honesty, integrity, and probity. T ese are ethical qualities required o students and healthcare pro essionals. T is honor/ integrity can only be achieved in an environment where intellectual honesty and personal integrity are highly valued—and where the responsibility or communicating and maintaining these standards is widely shared. In order to meet ARR certi cation requirements, candidates or the ARR examination must answer the question: “Have you ever been suspended, dismissed, or expelled

rom an educational program that you have attended?” In addition to reading and signing the “Written Consent under FERPA,” allowing the ARR to obtain speci c parts o their educational records concerning violations to an honor code i the student has ever been suspended, dismissed, or expelled rom an educational program attended. I the applicant answers “yes” to that question he or she must include an explanation and documentation o the situation with the completed application or certi cation. I the applicant has any doubts, he or she should contact the ARR Ethics Requirements Department at (651) 687–0048, ext. 8580. 4. (B) Every radiographic image must include (1) the patient’s name or ID number, (2) the side marker, right or le ; (3) the date o the examination; and (4) the identity o the institution or of ce. Additional in ormation may be included: the patient’s birth date or age, name o the attending physician, and the time o day. When multiple examinations (e.g., chest examinations or small bowel images) o a patient are made on the same day, it becomes crucial that the time the radiographs were taken be included on the image. T is allows the physician to track the patient’s progress. 5. (B) A radiographer who discloses con dential in ormation to unauthorized individuals may be ound guilty o invasion o privacy. I the disclosure is in some way detrimental or otherwise harm ul to the patient, the radiographer may also be accused o de amation. Spoken de amation is slander; written de amation is libel.

15

16

1: Patient Care and Education

6. (A) T e pre x iatr- is rom the Greek iatros, meaning “physician.” An iatrogenic in ection is one caused by physician intervention or by medical or diagnostic treatment/procedures. Examples include in ection ollowing surgery and nausea or other illness ollowing prescribed drug use. 7. (C) Reactions to contrast agents are named and categorized according to the body system(s) a ected, the nature o the reaction (i.e., allergic vs. nonallergic), and its severity (i.e., mild, moderate, or severe). T ese reactions are categorized as mild (a nonallergic reaction), anaphylactic (allergic reaction), and vasovagal (li e-threatening). Mild e ects are principally emotional and anxiety-based. T ey are characterized by anxiety, syncope, nausea, lightheadedness, and sometimes, a ew hives. T e patient usually requires reassurance and not medical attention. An anaphylactic reaction is a true allergic reaction to, or example, iodinated media and can lead to a li e-threatening situation. Immediate medical attention is required. Symptoms o anaphylactic reaction include laryngo/bronchospasm, hypotension, moderate-to-severe urticaria, angioedema, and tachycardia. A vasovagal reaction is li e-threatening and requires a declared emergency (“code”). Symptoms o a vasovagal reaction include bradycardia, hypotension, and no detectable pulse. T e ourth type o reaction, acute renal ailure, may not mani est or up to 48 hours ollowing injection o the contrast agent. Patients should noti y their physician i they experience any changes in their urinary habits or any other atypical symptoms. reatment would include hydration, dispensation o a diuretic (e.g., Lasix), and possibly even renal dialysis. 8. (C) Although each o these steps is part o a complete radiologic examination, an all-important rst step is care ul and accurate patient identi cation. Patient identi cation, and correctly matching the patient with the intended examination, is a routine activity in the healthcare environment. T e healthcare worker has primary responsibility or checking/ veri ying patient identity. Most acilities require checking at least two patient identi ers. Rigorous observance o “timeout” processes prior to procedures can avoid costly events, including those involving patient identi cation. 9. (B) Lidocaine (Xylocaine) is an antiarrhythmic used to prevent or treat cardiac arrhythmias

(dysrhythmia). Epinephrine (Adrenalin) is a bronchodilator. Bronchodilators may be administered in a spray mister, such as or asthma, or by injection to relieve severe bronchospasm. Nitroglycerin and verapamil are vasodilators. Vasodilators permit increased blood ow by relaxing the walls o the blood vessels. 10. (D) T e pathway by which in ectious organisms gain entry to the body is termed the portal o entry. Potential portals o entry include breaks in the skin, the gastrointestinal tract, mucous membranes o eyes, nose or mouth, the respiratory tract, and the urinary tract. Entry can be accomplished by ingestion, injection, inhalation, and across mucous membrane; the placenta serves as portal o entry between mother and etus. 11. (D) A parental route o drug administration is one that bypasses the digestive system. T e ve parenteral routes require di erent needle placements: under the skin (subcutaneous), through the skin and into the muscle (intramuscular), between the layers o the skin (intradermal), into a vein (intravenous), and into the subarachnoid space (intrathecal). 12. (D) It is essential that the radiographer take adequate or explanation o the procedure to the patient. In addition, there are times when the radiographer must inquire i proper diet and/or other preparation instructions have been ollowed prior to the examination. T e radiographer requires the cooperation o the patient throughout the course o the examination; there ore, providing a thorough explanation will alleviate patient anxieties and permit uller cooperation. Patient anxiety can also be reduced when the radiographer employs good listening skills, that is, looking at the patient (eye contact) and listening care ully without interruption and answering questions in a simple, clear, and direct manner, avoiding the use o elaborate medical terminology. 13. (B) Epidemiologic studies indicate that HIV and acquired immunode ciency syndrome (AIDS) can be transmitted only by intimate contact with blood or body uids o an in ected individual. T is can occur through the sharing o contaminated needles, through sexual contact, rom mother to baby at childbirth, and rom trans usion o contaminated

Answers: 6–18

blood. HIV and AIDS cannot be transmitted by inanimate objects. Hepatitis B virus (HBV) is another blood-borne in ection that a ects the liver. It is thought that more than 1 million people in the United States have chronic hepatitis B and, as such, can transmit the disease to others. Acid- ast bacillus (AFB) isolation is employed with patients suspected or known to be in ected with tuberculosis ( B). AFB isolation requires that the patient wear a mask to avoid the spread o acid- ast bacilli (in bronchial secretions) during coughing. 14. (A) T e mechanical device used to correct an ine ectual cardiac ventricular rhythm is a de brillator. T e two paddles attached to the unit are placed on a patient’s chest and used to introduce an electric current in an e ort to correct the dysrhythmia. Automatic implantable cardioverter de brillators (AICDs) are devices that are implanted in the body and that deliver a small shock to the heart i a li e-threatening dysrhythmia occurs. A cardiac monitor is used to display, and sometimes record, electrocardiographic (ECG) readings and some pressure readings. A crash cart is a supply cart with various medications and equipment necessary or treating a patient who is su ering rom a myocardial in arction or some other serious medical emergency. It is checked and restocked periodically. A resuscitation bag is used or ventilation, such as during CPR. 15. (B) Injectable medications are available in two di erent kinds o containers. An ampoule is a small container that usually holds a single dose o medication. A vial is a somewhat larger container that holds a number o doses o medication. T e term bolus is used to describe an amount o uid to be injected. A cara e is a narrow-mouthed container; it is not likely to be used or medical purposes. 16. (C) T e sudden cessation o productive ventilation and circulation is called cardiopulmonary arrest. T e radiographer should be trained in basic li e support (BLS) or healthcare providers. T e American Heart Association uses the acronym CAB, representing circulation, airway, breathing to help individuals remember CPR step sequence. Compressions should be about 100 per minute, beginning with 30 compressions. A er 30 compressions, airway should be established using the head-tilt,

17

chin-li movement. I the victim is not breathing normally, the pro essional rescuer should begin mouth-to-mouth breathing. One cycle is considered to be 30 chest compressions ollowed by two rescue breaths. 17. (A) In classi ying contrast agents, the total number o dissolved particles in solution per kilogram o water de nes the osmolality o the contrast agent. T e toxicity de nes how noxious or harm ul a contrast agent is. Contrast agents with low osmolality have been ound to cause less tissue toxicity than the ionic IV contrast agents. T e viscosity de nes the thickness or concentration o the contrast agent. T e viscosity o a contrast agent can a ect its injection rate. A thicker, or more viscous, contrast agent will be more dif cult to inject (more pressure is needed to push the contrast agent through the syringe and needle or the angiocatheter). T e miscibility o a contrast agent re ers to its ability to mix with body uids, such as blood. Miscibility is an important consideration in preventing thrombus ormation. It is generally pre erable to use a contrast agent with low osmolality and low toxicity because such an agent is sa er or the patient and less likely to cause any untoward reactions. When ionic and nonionic contrast agents are compared, a nonionic contrast agent has a lower osmolality. o urther understand osmolality, remember that whenever IV contrast media are introduced, there is a notable shi in uid and ions. T is shi is caused by an in ow o water rom interstitial regions into the vascular compartment, which increases the blood volume and cardiac output. Consequently, there will be an increase in systemic arterial pressure and peripheral vascular resistance with peripheral vasodilation. In addition, the pulmonary pressure and heart rate increase. When the e ects o osmolality on the patient are understood, it becomes clear that an elderly patient or one with cardiac disease or impaired circulation would greatly bene t rom the use o an agent with lower osmolality. 18. (B) When the radiographer initially greets the patient, and as the diagnostic examination progresses, the radiographer should be alert to the patient’s appearance and condition, and any subsequent changes in them. T ese are re erred to as objective signs. It is important to notice the color, temperature, and moistness o the patient’s skin.

18

1: Patient Care and Education

Paleness requently indicates weakness; the diaphoretic patient has pale, cool skin. T e ebrile patient is usually everish and exhibits hot, dry skin. “Sweaty” palms may indicate anxiety. A patient who becomes cyanotic (bluish lips, mucous membranes, or nail beds) needs oxygen and requires immediate medical attention. 19. (D) Misunderstandings between cultures can occur as a result o the use o gestures, which have di erent meanings in di erent countries. In the United States and Europe, the “thumbs up” gesture has a positive implication. However, it is considered rude in Australia and obscene in the Middle East. Other examples o potentially misunderstood gestures include: i you compliment a Mexican child, you must touch the head, while in Asia it is not acceptable to touch the head o a child; in the Philippines, it is rude to beckon with the index nger; urthermore, in the United States, people are com ortable speaking about 18 in apart, while in the Middle East, people stand much closer together when they talk; in England, people stand urther apart. 20. (C) T e legal doctrine res ipsa loquitur relates to a thing or matter that speaks or itsel . For instance, i a patient went into the hospital to have a kidney stone removed and ended up with an appendectomy, that speaks or itsel , and negligence can be proven. Respondeat superior is a phrase meaning “let the master answer” or “the one ruling is responsible.” I a radiographer were negligent, there may be an attempt to prove that the radiologist was responsible because the radiologist oversees the radiographer. Res judicata means a thing or matter settled by justice. Stare decisis re ers to a matter settled by precedent. 21. (D) Medical equipment that could contain latex includes disposable gloves, tourniquets, blood pressure cu s, stethoscopes, IV tubing, oral and nasal airways, enema tips, endotracheal tubes, syringes, electrode pads, catheters, wound drains, and injection ports. It should be noted that when powdered latex gloves are changed, latex protein/powder particles get into the air, where they can be inhaled and come in contact with body membranes. Studies have indicated that when unpowdered gloves are worn, there are extremely low levels o the allergyproducing proteins present.

22. (D) T e imaging examination requisition is usually printed with the patient’s personal in ormation (name, address, age, re erring/admitting physician’s name, and the patient’s hospital identi cation number). When examining patients who are admitted to the hospital, the requisition should also include the patient’s mode o travel to the radiology department or other imaging acility (e.g., wheelchair vs. stretcher), the type o examination to be per ormed, pertinent diagnostic in ormation, and any in ection control or isolation in ormation. T e radiographer, having access to con dential patient in ormation, must be mind ul o compliance with HIPAA regulations. 23. (B) Quantities o medication can be dispensed intravenously over a period o time via an IV in usion. A special in usion pump may be used to precisely regulate the quantity received by the patient. An IV push re ers to a rapid injection; the term bolus re ers to the quantity o material being injected. T e term hypodermic re ers to administration o medication by any route other than oral. 24. (D) T e patient’s rights can be exercised on the patient’s behal by a designated surrogate or proxy decision maker i the patient lacks decisionmaking capacity, is legally incompetent, or is a minor. Many people believe that potential legal and ethical issues can be avoided by creating an advance healthcare directive or living will. Since all persons have the right to make decisions regarding their own health care, this legal document preserves that right in the event an individual is unable to make those decisions. An advance healthcare directive, or living will, names the healthcare proxy authorized to make all healthcare decisions and can include speci cs regarding DNR (Do not resuscitate), DNI (Do not intubate), and/or other end-o -li e decisions. 25. (B) A omite is an inanimate object that has been in contact with an in ectious microorganism. A reservoir is a site where an in ectious organism can remain alive and rom which transmission can occur. Although an inanimate object can be a reservoir or in ection, living objects (such as humans) also can be reservoirs. For in ection to spread, there must be a host environment. Although an inanimate object may serve as a temporary host

Answers: 19–32

where microbes can grow, microbes ourish on and in the human host, where there are plenty o body uids and tissues to nourish and eed the microbes. A vector is an animal host o an in ectious organism that transmits the in ection via bite or sting. 26. (B) T ere are our stages o in ection. In the initial phase, the latent period, the in ection is introduced and lies dormant. As soon as the microbes begin to shed, the in ection becomes communicable. T e microbes reproduce (during the incubation period), and during the actual disease period, signs and symptoms o the in ection may begin. T e in ection is most active and communicable at this point. As the patient ghts o the in ection and the symptoms regress, the convalescent (recovery) phase occurs. 27. (C) Dyspnea (dif culty breathing) can precede a respiratory arrest event. Dyspnea can be caused by an aspirated oreign object, injury to the chest, tongue obstruction o airway in unresponsive person, drug overdose, etc. Dyspnea caused by a partially obstructed airway can mani est itsel in the patient by wheezing, noisy/labored breathing, cyanosis o the nailbeds and lips, distention o the neck veins, and anxiety. T e radiographer should not leave the patient alone, should call or assistance, assist the patient to a seated or semi-Fowler position, and prepare to assist with emergency treatment. 28. (D) oday we know that the most important precaution in the practice o aseptic technique is proper hand hygiene. T e radiographer’s hands should be thoroughly washed with soap and warm running water or at least 15 seconds be ore and a er each patient examination, or by using an alcohol sanitizer. I the aucet cannot be operated with the knee, it should be opened and closed using paper towels (to avoid contamination o or by the aucet). T e radiographer’s uni orm should not touch the sink. T e hands and orearms should always be kept lower than the elbows; care should be taken to wash all sur aces and between ngers. Hand lotions should be used to prevent hands rom chapping; broken skin permits the entry o microorganisms. Disin ectants, antiseptics, and germicides are substances used to kill pathogenic bacteria; they are requently used in hand hygiene substances. Alcohol-based hand sensitizers have been recommended as an alternative to handwashing with

19

soap and water, except when there is visible soiling or a er caring or a patient with Clostridium di cile in ection. 29. (D) Rules o good body mechanics include: when carrying a heavy object, hold it close to the body; the back should be kept straight; avoid twisting when li ing an object; bend the knees and use leg and abdominal muscles to li (rather than the back muscles); whenever possible, push or roll heavy objects (rather than li ing or pulling). o trans er the patient with maximum sa ety, the radiographer must correctly use certain concepts o body mechanics. First, a broad base o support lends greater stability; there ore, the radiographer should stand with his or her eet approximately 12 inches apart and with one oot slightly orward. Second, stability is achieved when the body’s center o gravity (center o the pelvis) is positioned over its base o support. For example, leaning away rom the central axis o the body makes the body more vulnerable to losing balance; i the eet are close together, balance is even more dif cult to maintain. 30. (C) When caring or a patient with an indwelling Foley catheter, place the drainage bag and tubing below the level o the bladder to maintain the gravity ow o urine. Placement o the tubing or bag above or level with the bladder will allow back ow o urine into the bladder. T is re ux o urine can increase the chance o developing a urinary tract in ection (U I). 31. (B) When trans erring patients, always help the patient trans er toward the strong side. T at is, begin with the stronger side closer to the x-ray table. Be certain that the wheels o stretchers and wheelchairs are locked during trans er. A two-person li is not always necessary; most patients can trans er with the care ul assistance o the radiographer. When assisting a patient in changing, rst remove clothing rom the una ected side. I this is done, removing clothing rom the a ected side will require less movement and e ort. 32. (B) Nonionic, low-osmolality iodinated contrast agents are associated with ar ewer side e ects and reactions than ionic, higher osmolality contrast agents. A side e ect is an e ect that is unintended but possibly expected and undamentally

20

1: Patient Care and Education

not harm ul. An adverse reaction is a harm ul unintended e ect that can be immediate or delayed. Possible side e ects o iodinated contrast agents include a warm, ushed eeling, a metallic taste in the mouth, nausea, headache, and pain at the injection site. Adverse reactions include itching, anxiety, rash or hives, vomiting, sneezing, dyspnea, and hypotension. 33. (C) T e normal blood pressure range or adult men and women is a 90 to 120 mm Hg systolic reading (le number) and a 50 to 70 mm Hg diastolic reading (right number). Systolic pressure is the contraction phase o the le ventricle, and diastolic pressure is the relaxation phase in the heart cycle. T ere ore, in the blood pressure reading 145/75, the systolic pressure o 145 is higher than desirable, and the diastolic pressure o 75 is also higher than desirable. Systolic pressure consistently above 140 and diastolic pressure consistently above 90 is considered hypertension. 34. (C) Facsimile transmission o health in ormation is convenient but should be used only to address immediate and urgent patient needs—and every precaution must be taken to ensure its con dentiality. It should be used only with prior patient authorization, when urgently needed or patient care, or when required or third-party payer ongoing hospitalization certi cation. T ese recommendations are made by the American Health In ormation Management Association (AHIMA). 35. (C) Verbal de amation o another, or slander, is a type o intentional misconduct. Invasion o privacy (i.e., public discussion o privileged and con dential in ormation) is intentional misconduct. However, i a radiographer leaves a weak patient standing alone to check images or get supplies and that patient alls and sustains an injury, that would be considered unintentional misconduct, or negligence. 36. (B) When helping a patient out o a wheelchair, it must rst be locked. T en, the ootrests must be moved up and aside to prevent the patient rom tripping over them or tilting the wheelchair orward. T e wheelchair should be placed at a 45-degree angle with the x-ray table or bed, with the patient’s stronger side closest toward the x-ray table or bed. When returning the patient to the

wheelchair, once the patient is seated, the ootrests should be lowered into place or the patient’s com ort. 37. (A) Dr. Elizabeth Kubler-Ross explains that loss requires gradual adjustment and involves several steps. T e rst is denial or isolation, where the individual o en re uses to accept the thought o loss or death. T e second step is anger, as the individual attempts to deal with eelings o helplessness. T e next is bargaining, in which the patient behaves as though “being good” like a “good patient” will be rewarded by a miraculous cure or return o the loss. Once the individual acknowledges that this is not likely to happen, depression is the next step. T is depression precedes acceptance, where the individual begins to deal with ate or loss. 38. (D) An unconscious patient requently is able to hear and understand all that is going on, even though he or she is unable to respond. T ere ore, while per orming the examination, the radiographer always should re er to the patient by name and take care to continually explain what is being done and reassure the patient. 39. (C) Cathartics stimulate de ecation and are used in preparation or radiologic examinations o the large bowel. Diuretics are used to promote urine elimination in individuals whose tissues are retaining excessive uid. Emetics induce vomiting, and antitussives are used to inhibit coughing. 40. (B) Healthcare-associated in ections (HAIs) are in ections acquired by patients while they are in the hospital; they are also termed nosocomial in ections. Many o these in ections are acquired by patients whose resistance has been diminished by their illness and are unrelated to the condition or which the patients were hospitalized. In ection resulting rom physician intervention is termed iatrogenic. T e CDC estimates that rom 5% to 15% o all hospital patients acquire some type o HAI. Hospital personnel can also become in ected (occupationally acquired in ection). Individuals weakened by illness or disease are more susceptible to in ection than are healthy individuals. T e most common HAI is the urinary tract in ection (U I), o en related to the use o urinary catheters, which can allow passage o pathogens into

Answers: 33–47

the patient’s body. Other types o HAIs include sepsis, wound in ection, and respiratory tract in ection. T ese are o en attributable to methicillin-resistant Staphylococcus aureus (MRSA) and vancomycinresistant enterococci (VRE). Droplet and airborne identi y types o transmission-based precautions. 41. (D) Medications can be administered in a number o ways. Parenteral administration re ers to drugs administered via intramuscular, subcutaneous, IV, or intrathecal routes—that is, any way other than by mouth. Intramuscular drug injections usually require that the needle orm a 90-degree angle o injection. For subcutaneous injections, the needle should orm a 45-degree angle. Intravenous injections generally require that the needle orm about a 15-degree angle with the arm. 42. (C) Ethnocentrism is the belie that one’s personal experience and perception o the world is superior to the experiences and perceptions o others, that is, the belie that one’s own cultural ways are superior to any other. Ethnocentrism can be ound in all cultures and is the most signi cant barrier to good communication. Ethnology is the comparative study o various cultures. Ethnobiology is the study o biological characteristics o various races. Ethnography is the study o a single society’s culture. 43. (D) Most institutions now have computerized, paperless systems or patient in ormation transmittal; these systems must ensure con dentiality in compliance with Health Insurance Portability and Accountability Act (HIPAA) o 1996 regulations. Only healthcare pro essionals having been trained in HIPAA compliance may have access to the computerized system via personal password, thus helping ensure con dentiality o patient in ormation. Computer les containing patient in ormation must be encrypted. I authorization or release o medical in ormation is given, a copy o that authorization must be kept on le. All medical records and other individually identi able health in ormation, whether electronic, on paper, or oral, are covered by HIPAA legislation and by subsequent Department o Health and Human Services (HHS) rules that took e ect in April o 2001. 44. (A) Iodinated contrast material can become somewhat viscous (i.e., thick and sticky) at normal room

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temperatures. T is makes injection much more dif cult. Warming the contrast medium to body temperature serves to reduce viscosity. T is may be achieved by placing the vial in warm water or putting it into a special warming oven. 45. (B) Cardiogenic shock is related to cardiac ailure and results rom inter erence with heart unction. It can occur in cases o cardiac tamponade, pulmonary embolus, or myocardial in arction. Hypovolemic shock is related to loss o large amounts o blood, either rom internal bleeding or rom hemorrhage associated with trauma. Neurogenic shock is associated with the pooling o blood in the peripheral vessels. T is occurs in cases o trauma to the central nervous system that results in decreased arterial resistance and pooling o blood in peripheral vessels. Septic shock, along with anaphylactic shock, generally is classi ed as vasogenic shock. 46. (D) T e Joint Commission ( ormerly the Joint Commission on the Accreditation o Health-care Organizations [JCAHO]) is the organization that accredits healthcare organizations in the United States. T e Joint Commission sets orth certain standards or medical records, both written and electronic. In keeping with these standards, all diagnostic and therapeutic orders must appear in the patient’s medical record or chart. In addition, patient identi cation in ormation, medical history, consent orms, and any diagnostic and therapeutic reports should be part o the patient’s permanent record. T e patient’s chart is a means o communication between various healthcare providers. 47. (B) Category-speci c isolations have been replaced by transmission-based precautions: airborne, droplet, and contact. Under these guidelines, some conditions or diseases can all into more than one category. Airborne precautions are employed with patients suspected or known to be in ected with tubercle bacillus ( B), chickenpox (varicella), or measles (rubeola). Airborne precautions require that the patient wear a string mask to avoid the spread o bronchial secretions or other pathogens during coughing. I the patient is unable or unwilling to wear a mask, the radiographer must wear one, and or a patient in airborne precautions that would be an N95 particulate respirator mask. T e

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radiographer should wear gloves, but a gown is required only i agrant contamination is likely. Patients under airborne precautions require a private, specially ventilated (negative-pressure) room. A private room is also indicated or all patients on droplet precautions, that is, with diseases transmitted via large droplets expelled rom the patient while speaking, sneezing, or coughing. T e pathogenic droplets can in ect others when they come in contact with mouth or nasal mucosa or conjunctiva. Rubella (“German measles”), mumps, and inf uenza are among the diseases spread by droplet contact; a private room is required or the patient, and healthcare practitioners should wear a string mask and may also wear gown and gloves as needed. Any diseases spread by direct or close contact, such as MRSA, conjunctivitis, and hepatitis A, require contact precautions. Contact precautions require a private patient room and the use o gloves, gown, and sometimes a mask or anyone coming in direct contact with the in ected individual or his or her environment. 48. (A) In ormed consent is required or procedures that involve risk; many imaging procedures require signed consent. In ormed consent is also required or procedures that are considered experimental, or or any research in which the patient is participating. T e consent orm must be complete prior to being signed; there should be no blank spaces on the consent orm when the patient signs it. T e patient must sign the consent orm be ore receiving sedation. T e physician named on the consent orm must per orm the procedure; no other physician should per orm it. In the case o a minor, a parent or guardian is required to sign the orm. I a patient is not competent, then the legally appointed guardian must sign the consent orm. Remember that obtaining consent is the physician’s responsibility, so the explanation o the procedural risks should be per ormed by the physician, not by the radiographer. T e in ormed consent can be revoked by the patient at any time. 49. (D) T e importance o e ective and pro essional patient communication skills cannot be overemphasized; the interaction between the patient and radiographer generally leaves the patient with a lasting impression o his or her healthcare experience. O course, communication re ers not only to the spoken word (i.e., verbal communication) but also to

unspoken/nonverbal communication. Facial expression can convey caring and reassurance or impatience and disapproval. Pursed lips, pointed ngers, rowns, and hands on hips all indicate disapproval. Similarly, a radiographer’s touch can convey his or her commitment to considerate care, or it can convey a rough, uncaring, hurried attitude. Making eye contact while speaking is generally considered polite and respect ul in the United States, whereas it can be considered just the opposite in other cultures (e.g., Asian, East Indian, Native American). Our appearance gives an impression about how we eel about our work and our patients; it is very much a part o communication and we should strive or a pro essional appearance/image. 50. (B) Many microorganisms can remain in ectious while awaiting transmission to another host. A contaminated inanimate object such as a ood utensil, doorknob, or IV pole is re erred to as a omite. A vector is an insect or animal carrier o in ectious organisms, such as a rabid animal, a mosquito that carries malaria, or a mouse/deer tick that carries Lyme disease. T ey can transmit disease through either direct or indirect contact. 51. (B) A circumstance in which both the healthcare provider’s and the patient’s actions contribute to an injurious outcome is termed contributory negligence. An example would be a patient who ails to ollow the physician’s orders or ails to show up or ollow-up care and then sues when the condition causes permanent damage. Another example would be a patient who deliberately gives alse in ormation about the ingestion o drugs, leading to adverse e ects rom medications administered. Most states do not completely dismiss injury i there has been negligence on the part o the healthcare institution, even i the patient’s actions contributed substantially to the injury. Rather, comparative negligence is applied, where the percentage o the injury owing to the patient’s actions is compared with the total amount o injury. A jury may decide that a physician was negligent in his or her actions, but because the patient lied about using an illegal street drug that contributed to the injurious outcome, the patient is 80% responsible or his or her condition. T e party suing may be awarded $100,000 or injuries but actually would receive only $20,000. Gross negligence occurs when there is will ul or deliberate neglect o the patient. Assault, battery, invasion o

Answers: 48–59

privacy, alse imprisonment, and de amation o character all all under the category o intentional misconduct. 52. (C) Extravasation o contrast media into surrounding tissue is potentially very pain ul. I it does occur, the needle should be removed and the extravasation cared or immediately (be ore looking or another vein). First, pressure should be applied to the vein until bleeding stops. Application o a cold pack to the a ected area helps to relieve pain, and elevate the part. Application o a warm towel at the injection site can hasten absorption o any contrast medium. 53. (D) T e normal blood pressure range or adult men and women is a 90 to 120 mm Hg systolic reading (le number) and a 50 to 70 mm Hg diastolic reading (right number). Systolic pressure is the contraction phase o the le ventricle, and diastolic pressure is the relaxation phase in the heart cycle. Systolic pressure consistently above 140 and diastolic pressure consistently above 90 is considered hypertension. 54. (D) When moving heavy objects, there are several rules that will reduce back strain. When carrying a heavy object, hold it close to your body. Your back should be kept straight; avoid twisting. When li ing an object, bend at the knees and use leg and abdominal muscles to li (rather than your back muscles). Whenever possible, push or roll heavy objects (i.e., mobile unit), rather than pulling or li ing. 55. (D) None o the statements in the question is alse; all are true. Oxygen is classi ed as a drug and must be prescribed by a physician. T e rate and mode o delivery o oxygen must be speci ed in the physician’s orders. It can be ordered to be delivered continuously or as needed. 56. (A) It is unlikely that the radiographer will be aced with a wound hemorrhage because bleeding rom wounds is controlled be ore the patient is seen or x-ray examination. However, i a patient does experience hemorrhaging rom a wound, you should apply pressure to the bleeding site and call or assistance. Delay can lead to serious blood loss. 57. (B) A double-contrast GI examination requires that the patient ingest gas-producing powder, crystals, pills, or beverage ollowed by a small amount o

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high-density barium. T e patient then may be asked to roll in the recumbent position in order to coat the gastric mucosa while the carbon dioxide expands. T is procedure provides optimal visualization o the gastric walls. Although a double-contrast BE uses a negative contrast agent, it is not ingested but rather is delivered rectally. An oral cholecystogram can be per ormed approximately 3 hours a er ingestion o special ipodate calcium granules. An IVU requires an IV injection o iodinated contrast medium. 58. (C) Category-speci c isolations have been replaced by transmission-based precautions: airborne, droplet, and contact. Under these guidelines, some conditions or diseases can all into more than one category. Airborne precautions are employed with patients suspected or known to be in ected with tubercle bacillus ( B), chickenpox (varicella), or measles (rubeola). Airborne precautions require that the patient wear a string mask to avoid the spread o bronchial secretions or other pathogens during coughing. I the patient is unable or unwilling to wear a mask, the radiographer must wear a string mask to avoid the spread o bronchial secretions or other pathogens during coughing. T e radiographer should wear gloves, but a gown is required only i agrant contamination is likely. Patients under airborne precautions require a private, specially ventilated (negative-pressure) room. A private room is also indicated or all patients on droplet precautions, that is, with diseases transmitted via large droplets expelled rom the patient while speaking, sneezing, or coughing. T e pathogenic droplets can in ect others when they come in contact with mouth or nasal mucosa or conjunctiva. Rubella (“German measles”), mumps, and inf uenza are among the diseases spread by droplet contact; a private room is required or the patient, and healthcare practitioners should wear a string mask i within 3 o patient. Any diseases spread by direct or close contact, such as methicillin-resistant Staphylococcus aureus (MRSA), conjunctivitis, and Rotavirus, require contact precautions. Contact precautions require a private patient room and the use o gloves and gowns or anyone coming in direct contact with the in ected individual or his or her environment. 59. (D) Medications can be administered in a number o ways: orally, sublingually, topically, and parentally. Oral denotes delivery by mouth (e.g., analgesics, etc.). Sublingual re ers to medication placed

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under the tongue and dissolved there or rapid absorption (e.g., nitroglycerine). opical denotes medication that is applied directly onto the skin (e.g., topical anesthetics and transdermal patches). A parental route o drug administration is one that bypasses the digestive system. T e ve parenteral routes require di erent needle placements: under the skin (subcutaneous), through the skin and into the muscle (intramuscular), between the layers o the skin (intradermal), into a vein (intravenous), and into the subarachnoid space (intrathecal). 60. (D) Although it is never the responsibility o the radiographer to diagnose a patient, it is the responsibility o every radiographer to be alert. T e patient should not be subjected to unnecessary radiation rom an unwanted examination. Rather, it is the radiographer’s responsibility to check with the re erring physician and report the patient’s complaint. 61. (C) A Swan–Ganz catheter is a speci c type o IV catheter used to measure the pumping ability o the heart, to obtain pressure readings, and to introduce medications and IV uids. A pacemaker is a device that is inserted under the patient’s skin to regulate heart rate. Pacemakers may be permanent or temporary. Chest tubes are used to remove uid or air rom the pleural cavity. Any o these items may be identi ed on a chest radiograph, provided that the cassette is properly positioned and the correct exposure actors are employed. I the physician is interested in assessing the proper placement o a Swan–Ganz catheter, the lungs may have to be slightly overexposed to clearly delineate the proper placement o the tip o the Swan–Ganz catheter, which will overlap the denser cardiac silhouette. A urinary catheter will not appear on a chest radiograph. 62. (B) A patient who is having a BE generally is required to have a low-residue diet or 1 or 2 days, ollowed by cathartics and cleansing enemas prior to the examination. Any retained ecal material can simulate or obscure pathology. A patient who is scheduled or a pyelogram must have the preceding meal withheld to avoid the possibility o aspirating vomitus in case o an allergic reaction. A metastatic survey does not require the use o contrast media, and no patient preparation is necessary.

63. (A) When per orming bedside radiography in a contact isolation room, the radiographer should wear a gown and gloves. T e IPs are prepared or the examination by placing a pillowcase over them to protect them rom contamination. Whenever possible, one person should manipulate the mobile unit and remain “clean,” whereas the other handles the patient. T e mobile unit should be cleaned with a disin ectant on exiting the patient’s room, not prior to entering. 64. (C) T e Levin and Salem-sump tubes are NG tubes used or gastric decompression. T e Salem-sump tube is radiopaque and has a double lumen. One lumen is or gastric air compression, and the other is or removal o uids. T e Levin tube is a single-lumen tube that is used to prevent accumulation o intestinal liquids and gas during and ollowing intestinal surgery. T e Swan–Ganz IV catheter is advanced to the pulmonary artery and used to measure various heart pressures. 65. (D) A catheter placed in a large vein is called a central venous line. It can be used to deliver requent medications or nutrition or to monitor cardiac pressures. Catheters can vary in size and number o lumens depending on intended use. T e Port-aCath is a totally implanted access port, and the peripherally inserted central catheter (PICC) is a peripherally inserted central catheter—they both permit long-term intravenous treatment. T e Swan–Ganz catheter is advanced to the pulmonary artery and is used to measure the pumping ability o the heart, to obtain pressure readings, and to introduce medications and IV uids. T e Levin and Salem-sump tubes are NG tubes used or gastric decompression. T e Salem-sump tube is radiopaque and has a double lumen. One lumen is or gastric air compression, and the other is or removal o uids. 66. (B) T e most e ective method o sterilization is moist heat, using steam under pressure. T is is known as autoclaving. Sterilization with dry heat requires higher temperatures or longer periods o time than sterilization with moist heat. Chemical sterilization is a low temperature sterilization. Ethylene oxide is used to sterilize items that cannot tolerate high temperatures or moisture. Pasteurization is moderate heating with rapid cooling; it is used requently in the commercial preparation o milk and alcoholic beverages such as wine and beer. It is

Answers: 60–73

not a orm o sterilization. Freezing also can kill some microbes, but it is not a orm o sterilization. 67. (C) Emphysema is a progressive disorder caused by long-term irritation o the bronchial passages, such as by air pollution or cigarette smoking. Emphysema patients are unable to exhale normally because o loss o elasticity o alveolar walls. I emphysema patients receive oxygen, it is usually administered at a very slow ow rate because their respirations are controlled by the level o carbon dioxide in the blood. 68. Healthcare-associated in ections (HAIs) are in ections acquired by patients while they are in the hospital or other healthcare acility; they are also termed nosocomial in ections. Many o these in ections are acquired by patients whose resistance has been diminished by their illness and are unrelated to the condition or which the patients were hospitalized. In ection resulting rom physician intervention is termed iatrogenic. T e CDC estimates that rom 5% to 15% o all hospital patients acquire some type o HAI. Hospital personnel can also become in ected (occupationally acquired in ection). Microorganisms can remain in ectious while awaiting transmission to another host. A contaminated inanimate object such as a ood utensil, doorknob, or IV pole is re erred to as a omite. A vector is an insect or animal carrier o in ectious organisms, such as a rabid animal, a mosquito that carries malaria, or a mouse/deer tick that carries Lyme disease. 69. (B) Other names or an intermittent injection port is saline lock or heparin lock. Intermittent injection ports are used or patients who will require requent or regular injections. An intravenous catheter is placed in the vein, and an external adapter with a diaphragm allows or repeated injections. T is helps to prevent the ormation o scarred, sclerotic veins as a result o requent injections at the same site. Intermittent injection ports provide more reedom than an IV in usion, which also allows or repeated access. Hypodermic needles usually are used or drawing blood or drawing up uids, whereas a butterf y needle usually is used or venipuncture. 70. (C) In ormed consent is required or procedures that involve risk; many imaging procedures require signed consent. In ormed consent is also required

25

or procedures that are considered experimental, or or any research in which the patient is participating. T e consent orm must be complete prior to being signed; there should be no blank spaces on the consent orm when the patient signs it. T e patient must sign the consent orm be ore receiving sedation. T e physician named on the consent orm must per orm the procedure; no other physician should per orm it. In the case o a minor, a parent or guardian is required to sign the orm. I a patient is not competent, then the legally appointed guardian must sign the consent orm. Remember that obtaining consent is the physician’s responsibility, so the explanation o the procedural risks should be per ormed by the physician, not by the radiographer. T e in ormed consent can be revoked by the patient at any time. 71. (C) It is recommended that a radiographer wear protective eye gear (goggles) during any procedure in which there might be splattering o blood or body uids. T is includes both angiography and biopsy/aspiration procedures. T is would not be expected during a routine upper GI examination. 72. (C) T e BUN level indicates the quantity o nitrogen in the blood in the orm o urea. T e normal concentration is 8 to 20 mg/mg/dL. BUN and creatinine blood chemistry levels should be checked prior to beginning an IVU. An increase in the BUN level o en indicates decreased renal unction. Increased BUN and/or creatinine levels may orecast an increased possibility o contrast media–induced renal e ects and poor visualization o the renal collecting systems. T e normal creatinine range is 0.6 to 1.5 mg/dL. 73. (A) Met ormin (Glucophage) is an antidiabetic agent indicated or the treatment o type 2 diabetes mellitus. Radiologic examinations requiring the use o intravascular-iodinated contrast agents can lead to acute alteration o renal unction and have been associated with lactic acidosis in patients taking metormin. T e manu acturer recommends that patients taking met ormin discontinue it at the time o or prior to the x-ray examination and withhold it or 48 more hours ollowing the examination. T e medication should be continued only a er adequate renal unction has been indicated by blood test (blood urea nitrogen [BUN], serum creatinine, glomerular ltration rate [GFR]).

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74. (A) Volvulus and intussusception both involve a mechanical “closure” or obstruction o the intestinal lumen by a change in the continuous pathway o the GI tract—volvulus by a twisting o the bowel on itsel causing obstruction and intussusception by “telescoping” o the bowel causing obstruction. Meconium ileus is another orm o mechanical obstruction where meconium ( rst eces o a newborn) becomes hardened and impacted, causing obstruction. Paralytic (or adynamic) ileus, however, is an obstruction caused by loss o peristaltic movement o the intestine. 75. (C) An individual whose coronary arteries are not carrying enough blood to the heart muscle (myocardium) as a result o partial or complete blockage o a cardiac vessel experiences crushing pain in the chest, requently radiating to the le jaw and arm. T is is termed angina pectoris. It may be relieved by the drug nitroglycerin, which dilates the coronary arteries, thus acilitating circulation. achycardia re ers to rapid heart rate, and bradycardia, to slow heart rate. Syncope is ainting. 76. (B) T e presence o surgical clips, cochlear implant, neurostimulator, any implanted metal device or prosthesis, are contraindications or magnetic resonance imaging (MRI). MRI can be per ormed or a herniated disk and subdural bleeding. Dental llings do not contraindicate MRI. 77. (C) T e relatively low-osmolality and nonionic, water-soluble contrast media available to radiology departments have outstanding advantages, especially or patients with a history o allergic reaction. T ey were used originally or intrathecal injections (myelography), but they were quickly accepted or intravascular injections as well. Side e ects and allergic reactions are less likely and less severe with these media. One o the very signi cant disadvantages is their high cost compared with that o ionic contrast media. 78. (B) Gerontology, or geriatrics, is the study o the elderly. Although bone demineralization and loss o muscle mass occur to a greater or lesser degree in most elderly individuals, the radiographer must not assume that all gerontologic patients are hard o hearing, clumsy, or not mentally alert. oday, many elderly people remain very active, staying mentally and physically agile well into their

so-called golden years. T e radiographer must keep this in mind as he or she provides age-speci c care to the gerontologic patient. 79. (A) When a two-member team o radiographers is per orming mobile radiography on a patient with contact precautions, such as an MRSA patient, one radiographer remains “clean”—that is, he or she has no physical contact with the patient. T e clean radiographer will position the mobile unit and make the exposure. T e other member o the team will position the cassette and retrieve the cassette. As the two radiographers old down the cassette’s protective plastic cover, the “clean” radiographer will remove the cassette rom the plastic. Both radiographers should be protected with gowns, gloves, and possibly masks i the patient is on contact precautions. In addition, a er the examination is completed, the mobile unit should be cleaned with a disin ectant. Conditions requiring the use o contact precautions also include Vancomycin-resistant Enterococcus (VRE) and Rotavirus. 80. (D) All these symptoms are related to a respiratory reaction. T ere also may be dyspnea, asthma attack, or cyanosis. T e patient who has received contrast media should be watched closely. I any symptoms arise, the radiologist should be noti ed immediately. 81. (C) I a patient in your care asks to see his or her medical records/chart, the appropriate response is to re er the patient to his or her physician. Patients do have the right to review their own medical records; however, the patient should do so in the presence o the physician so that in ormation is not misinterpreted and so that the physician can address concerns or answer questions. It is not appropriate to provide the patient with their records, nor is it appropriate to deceive the patient into believing that the records are not available or viewing or that the patient has no right to review them. 82. (B) Cyanosis is a condition resulting rom a de ciency o oxygen circulating in the blood. It is characterized by bluish discoloration o the gums, nailbeds, earlobes, and the area around the mouth. Cyanosis may be accompanied by labored breathing or other types o respiratory distress. 83. (D) Category-speci c isolations have been replaced by transmission-based precautions: airborne, droplet,

Answers: 74–90

and contact. Under these guidelines, some conditions or diseases can all into more than one category. Any diseases spread by direct or close contact, such as MRSA, conjunctivitis, and Rotavirus, require contact precautions. Contact precautions require a private patient room and the use o gloves, gown and possibly a mask or anyone coming in direct contact with the in ected individual or his or her environment. Airborne precautions are employed with patients suspected or known to be in ected with tubercle bacillus ( B), chickenpox (varicella), or measles (rubeola). Airborne precautions require that the patient wear a string mask to avoid the spread o bronchial secretions or other pathogens during coughing. I the patient is unable or unwilling to wear a mask, the radiographer must wear a mask. T e radiographer should wear gloves, but a gown is required only i agrant contamination is likely. Patients under airborne precautions require a private, specially ventilated (negative-pressure) room. A private room is also indicated or all patients on droplet precautions, that is, with diseases transmitted via large droplets expelled rom the patient while speaking, sneezing, or coughing. T e pathogenic droplets can in ect others when they come in contact with mouth or nasal mucosa or conjunctiva. Rubella (“German measles”), mumps, and inf uenza are among the diseases spread by droplet contact; a private room is required or the patient, and healthcare practitioners should wear a string mask and possibly gloves and gown as needed. 84. (B) A patient who has been NPO since midnight or who is anxious, rightened, or in pain may su er an episode o syncope ( ainting) on exertion. T e patient should be helped to a recumbent position with eet elevated to increase blood ow to the head. A patient who eels like ainting should never be le alone. 85. (C) Urticaria is a vascular reaction resulting in dilated capillaries and edema and causing the patient to break out in hives. T e medical term or nosebleed is epistaxis. Vertigo re ers to a eeling o “whirling” or a sensation that the room is spinning. Some possible causes o vertigo include inner ear in ection and acoustic neuroma. An aura may be classi ed as either a eeling or a sensory response (such as ashing lights, tasting metal, or smelling co ee) that precedes an episode such as a seizure or a migraine headache.

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86. (A) Blood pressure is measured in millimeters o mercury (mm Hg). Heart rate, or pulse, is measured in units o beats per minute. emperature is measured in degrees Fahrenheit (°F). Oxygen delivery is measured in units o liters per minute (L/min). able 1-1 outlines the normal ranges or vital signs in healthy adults. TABLE 1-1. NORMAL RANGES FOR VITAL SIGNS IN ADULTS Blood pressure Pulse rate Temperature Respiration rate

110–140 mmHg/60–80 mmHg 60–100 beats/min 97.7°F–99.5°F 12–20 breaths/min

87. (C) Veracity (i.e., sincerity) is not only telling the truth but also not practicing deception. Autonomy is the ethical principle that is related to the theory that patients have the right to decide what will or will not be done to them. Bene cence is related to the idea o doing good and being kind. Fidelity is aith ulness and loyalty. 88. (C) alipes is the term used to describe congenital club oot. T ere are several types o talipes, generally characterized by a de ormed talus and a shortened Achilles tendon, giving the oot a club oot appearance. Osteochondritis (Osgood–Schlatter disease) is a pain ul incomplete separation o the tibial tuberosity rom the tibial sha . It is o en seen in active adolescent boys. Coxa plana (Legg–Calvé–Perthes disease) is ischemic necrosis leading to attening o the emoral head. Muscular dystrophy is a congenital disorder characterized by wasting o skeletal muscles. 89. (D) When scheduling patient examinations, it is important to avoid the possibility o residual contrast medium covering areas that will be o interest on later examinations. T e IVU (also re erred to as an intravenous pyelogram [IVP]) should be scheduled rst because the contrast medium used is excreted rapidly. T e BE should be scheduled next. Finally, the upper GI series is scheduled. T ere should not be enough barium remaining rom the previous BE to inter ere with the examination o the stomach or duodenum, although a preliminary scout image should be taken in each case. 90. (D) Hypochlorite bleach (Clorox) and Lysol are examples o disin ectants. Disin ectants are used in radiology departments to clean equipment and to remove microorganisms rom areas such as

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1: Patient Care and Education

radiographic tables. Antiseptics are also used to stop the growth o microorganisms, but they are o en applied to the skin, not to radiographic equipment. Anti ungal medications can be administered systemically or topically to treat or prevent ungal in ections. Antibacterial medications (bacteriostatics) also can be administered systemically or externally. etracycline is a systemic antibacterial medication. 91. (D) Ventricular septal de ect is a congenital heart condition characterized by a hole in the interventricular septum that allows oxygenated and unoxygenated blood to mix. Some interventricular septal de ects are small and close spontaneously; others require surgery. Coarctation o the aorta is a narrowing or constriction o the aorta. Atrial septal de ect is a small hole (the remnant o the etal oramen ovale) in the interatrial septum. It usually closes spontaneously in the rst months o li e; i it persists or is unusually large, surgical repair is necessary. T e ductus arteriosus is a short etal blood vessel connecting the aorta and pulmonary artery that usually closes within 10 to 15 hours a er birth. A patent ductus arteriosus is one that persists and requires surgical closure. 92. (B) Patients arriving at the emergency department (ED) with suspected spinal injury should not be moved. Anteroposterior (AP) and horizontal lateral projections o the suspected area should be evaluated and a decision made about the advisability o urther images. For a lateral projection, the patient should be moved along one plane, that is, rolled like a log. It is imperative that twisting motions be avoided. 93. (D) T e cycle o in ection includes our components: a susceptible host, a reservoir o in ection, a pathogenic organism, and a mode o transmission. Pathogenic organisms are microscopic and include bacteria, ungi, and viruses. T e reservoir o in ection is the environment in which the microorganism thrives; this can be the human body. A susceptible host may have reduced resistance to in ection. T e mode o transmission is either direct (i.e., touch) or indirect (i.e., vector, omite, or airborne. 94. (B) T e diaphragm is the major muscle o respiration. On inspiration/inhalation, the diaphragm and abdominal viscera are depressed, enabling lling and expansion o the lungs, accompanied by

upward movement o the sternum and ribs. During expiration/exhalation, air leaves the lungs, and they de ate while the diaphragm relaxes and moves to a more superior position along with the abdominal viscera. As the diaphragm relaxes and moves up, the sternum and ribs move in eriorly. 95. (D) A tort is an intentional or unintentional act that involves personal injury or damage to a patient. Allowing a patient to be exposed to unnecessary radiation, either by neglecting to shield the patient or by per orming an unwanted examination, would be considered a tort, and the radiographer would be legally accountable. Other examples o negligent/ unintentional torts can include imaging the wrong patient, or injury to a patient as a result o a all when le unattended on an x-ray table, in a radiographic room, or on a stretcher without side rails or sa ety belt. Radiographing the wrong patient or opposite limb are other examples o negligence/ unintentional tort. Immobilizing a patient against his/her will is an example o an intentional tort. 96. (C) Because hospitals are the re uge o the sick, they can also be places o disease transmission unless proper in ection prevention and control guidelines are ollowed. When cleaning contaminated objects or suraces such as the radiographic table, it is important to clean rom the least contaminated to the most contaminated area and rom the top down. Soiled gowns and linens should be olded rom the outside in and disposed o properly. When the patient’s skin is being prepared or surgery, it is o en cleaned in circular motion starting rom the center and working outward; however, this motion is not used or objects or sur aces. 97. (B) A radiographer who per orms the wrong examination on a patient may be charged with battery. Battery re ers to the unlaw ul laying o hands on a patient. T e radiographer also could be charged with battery i a patient is moved about roughly or touched in a manner that is inappropriate or without the patient’s consent. Assault is the threat o touching or laying hands on someone. I a patient eels threatened by a practitioner, either because o the tone or pitch o the practitioner’s voice or because the practitioner uses words that are threatening, the practitioner can be accused o assault. False imprisonment may be considered i a patient is ignored a er stating that she no longer wishes to continue with the procedure or i restraining devices

Answers: 91–106

are used improperly or used without a physician’s order. T e accusation o de amation can be upheld when patient con dentiality is not respected and, as a result, the patient su ers embarrassment or mockery. 98. (B) T e two most common types o chronic in ammation o the intestines are ulcerative colitis and Crohn’s disease. T e latter can attack any part o the GI tract and extends through all layers o the intestinal wall (there ore the possibility o orming stulous tracks to contiguous structures). Ulcerative colitis attacks only the large bowel and only the mucosal layer o the intestinal wall. Curiously, cigarette smoking increases the risk or Crohn’s disease and decreases the risk or ulcerative colitis. Intussusception is an obstructive disorder. 99. (C) racheostomy is the surgical opening o the trachea to provide and secure an open airway. A tracheostomy is o en per ormed in emergency situations when there is upper airway obstruction, that is, above the level o the larynx. T e tracheostomy patient will have dif culty speaking as a result o redirection o the air past the vocal cords. Gurgling or rattling sounds coming rom the trachea indicate an excess accumulation o secretions, requiring suction with sterile catheters. A tracheostomy tube must not be moved. Any rotation or movement o the tracheostomy tube may cause it to become dislodged, and an obstructed airway could result. 100. (A) It is generally recommended that the IV bottle/ bag be kept 18 to 24 inches above the level o the vein. I the container is too high, the pressure o the IV uid can cause it to pass through the vein into surrounding tissues, causing a pain ul and potentially harm ul condition. I the IV container is too low, blood may return through the needle into the tubing, orm a clot, and obstruct the ow o IV uid. 101. (D) A private room is indicated or all patients on droplet precaution; that is, diseases transmitted via large droplets expelled rom the patient while speaking, sneezing, or coughing. T e pathogenic droplets can in ect others when they come in contact with mouth or nasal mucosa or conjunctiva. Rubella (“German measles”), mumps, and inf uenza are among the diseases spread by droplet contact; a private room is required or the patient,

29

and healthcare practitioners must wear a regular (string) mask to enter a droplet precautions isolation room. 102. (C) A Protective Environment or Neutropenic Precautions (sometimes re erred to as expanded precautions) as indicated are used to keep the susceptible patient rom becoming in ected. Patients who have su ered burns have lost a very important means o protection, their skin, and there ore have increased susceptibility to bacterial invasion. Patients whose immune systems are depressed have lost the ability to combat in ection and hence are more susceptible to in ection. Active B requires airborne precautions, not expanded precautions. 103. (C) Whenever a per oration o the GI tract is suspected, a water-soluble contrast agent (such as Gastrogra n or oral Hypaque) should be used because it is easily absorbed rom within the peritoneal cavity. Leakage o barium sul ate into the peritoneal cavity can have serious consequences. Water-soluble contrast agents also may be used in place o barium sul ate when the possibility o barium impaction exists. Oil-based contrast agents are used rarely today. 104. (A) Angina pectoris is a crushing chest pain caused by a circulatory disturbance o the coronary arteries. Nitroglycerin is used to dilate blood vessels (vasodilation) and decrease blood pressure in the treatment o pain rom angina pectoris. Nitroglycerin usually is given sublingually and thus is absorbed directly into the bloodstream. 105. (B) Syncope, or ainting, is the result o a drop in blood pressure caused by insuf cient blood (oxygen) ow to the brain. T e patient should be helped into a dorsal recumbent position with eet elevated to acilitate blood ow to the brain. 106. (B) T e diameter o a needle is the needle’s gauge. T e higher the gauge number, the smaller is the diameter and the thinner is the needle. For example, a very tiny-gauge needle (25 gauge) may be used on a pediatric patient or an IV injection, whereas a large-gauge needle (16 gauge) may be used or donating blood. T e hub o a needle is the portion o the needle that attaches to a syringe. T e length o the needle varies depending on its use. A longer

30

1: Patient Care and Education

needle is needed or intramuscular injections, whereas a shorter needle is used or subcutaneous injection. T e bevel o the needle is the slanted tip o the needle. For IV injections, the bevel always should ace up. 107. (D) Adverse reactions to the intravascular administration o iodinated contrast media are not uncommon, and although the risk o a li e-threatening reaction is relatively low, the radiographer must be alert to recognize the situation and deal with it e ectively should a serious reaction occur. A minor reaction is characterized by ushed appearance and nausea and, occasionally, by vomiting and a ew hives. Early symptoms o a possible anaphylactic reaction include constriction o the throat, possibly because o laryngeal edema, dysphagia (dif culty swallowing), and itching o the palms and soles. T e radiographer must maintain the patient’s airway, summon the radiologist, and call a “code.” 108. (B) T e patient is said to be in the rendelenburg position when the head is positioned lower than the eet. T is position is help ul in several radiographic procedures, such as separating redundant bowel loops and demonstration o hiatal hernias. It is also used in treating shock. In the Fowler position, the head is higher than the eet. T e Fowler position relaxes abdominal muscles and promotes maximum chest expansion with resultant improved lung oxygenation. T e Sims position is the le posterior oblique (LPO) position with the right leg exed up or insertion o the enema tip. T e Stenver position is a radiographic position or imaging the mastoids. 109. (C) T e normal average rate o respiration or a healthy adult patient is between 12 and 20 breaths/ min. For children, the rate is higher, averaging between 20 and 30 breaths/min. In addition to monitoring the respiratory rate, it is also important to monitor the depth (shallow or labored) and pattern (regularity) o respiration. A respiratory rate greater than 20 breaths/min in an adult would be considered tachypnea. 110. (B) Epinephrine (Adrenalin) is the vasopressor used to treat an anaphylactic reaction or cardiac arrest. Nitroglycerin is a vasodilator. Hydrocortisone is a steroid that may be used to treat bronchial asthma, allergic reactions, and in ammatory reactions. Digitoxin is used to treat cardiac brillation.

111. (B) In ectious microorganisms can be transmitted rom patients to other patients or to healthcare workers and rom healthcare workers to patients. T ey are transmitted by means o either direct or indirect contact. Direct contact involves touch. Diseases transmitted by direct contact include skin in ections such as boils and sexually transmitted diseases such as syphilis and AIDS. Direct contact with droplets o nasal or oral secretions rom a sneeze or cough is re erred to as droplet contact. Indirect contact involves transmission o microorganisms via airborne contamination, omites, and vectors. Pathogenic microorganisms expelled rom the respiratory tract through the mouth or nose can be carried as evaporated droplets through the air or dust and settle on clothing, utensils, or ood. Patients with respiratory tract in ections or disease transported to the radiology department there ore should wear a mask to prevent such transmission during a cough or sneeze; it is not necessary or the healthcare worker to wear a mask (as long as the patient does). Many microorganisms can remain in ectious while awaiting transmission to another host. A contaminated inanimate object such as a ood utensil, doorknob, or IV pole is re erred to as a omite. A vector is an insect or animal carrier o in ectious organisms, such as a rabid animal, a mosquito that carries malaria, or a tick that carries Lyme disease. T ey can transmit disease through either direct or indirect contact. 112. (C) Frequent and correct hand hygiene is an essential part o medical asepsis; it is the best method or avoiding the spread o microorganisms. Hand hygiene can be accomplished with alcohol-based hand sanitizers i there is no actual soiling on the skin or the patient does not have Clostridium di cile, or by washing with soap and water. I the water aucet cannot be operated with the knee or a oot pedal, it should be opened and closed using paper towels. Care should be taken to wash all sur aces o the hand and between the ngers thoroughly. T e hands and orearms always should be kept below the elbows. Hand lotions should be used requently to keep hands rom chapping. Unbroken skin prevents the entry o microorganisms; dry, cracked skin breaks down that de ense and permits the entry o microorganisms. 113. (D) Physicians o en prescribe a mild laxative to aid in the elimination o barium sul ate. I a

Answers: 107–120

laxative is not given, the patient should be instructed to increase dietary uid and ber and to monitor bowel movements (the patient should have at least one within 24 hours). Patients should also be aware o the white appearance o their stool that will be present until all barium is expelled. 114. (D) T e our vital signs are temperature, pulse, respiration, and blood pressure. Because radiographers may be required to take vital signs in an emergency, they should practice these skills. A thermometer is required to measure a patient’s temperature. A watch with a second hand is required to measure a patient’s pulse and respiration. o measure blood pressure, a blood pressure cu , sphygmomanometer, and stethoscope are required. T is is the skill that the radiographer should practice most requently because it is the one most likely to be needed in an emergency situation. 115. (D) T e medical abbreviation pc means “a er meals.” “T ree times a day” is indicated by the abbreviation tid. T e abbreviation qid means “ our times a day.” “Every hour” is represented by qh. 116. (D) Oxygen is taken into the body and supplied to the blood to be delivered to all body tissues. Any tissue(s) lacking in or devoid o an adequate blood supply can su er permanent damage or die. Oxygen may be required in cases o severe anemia, pneumonia, pulmonary edema, and shock. Symptoms o inadequate oxygen supply include dyspnea, cyanosis, diaphoresis, retraction o intercostal spaces, dilated nostrils, and distension o the veins o the neck. T e patient who experiences any o these symptoms will be very anxious and must not be le unattended. T e radiographer must call or help, assist the patient to a sitting or semi-Fowler position (the recumbent position makes breathing more dif cult), and have oxygen and emergency drugs available. 117. (D) Diversity o culture is o en thought o as ethnic diversity—a di erence in nationality. But cultural groups include religious groups, age groups, racial groups, socioeconomic groups, geographic groups, handicapped groups, generational groups, gender groups, sexual pre erence groups, etc. Ethnocentrism is the belie that one’s own cultural ways are superior to any other way. Ethnocentrism can be ound in all cultures and is

31

the most signi cant barrier to good communication. It is essential that we have an awareness o our own ethnocentrism. 118. (B) Double-contrast studies o the large bowel are particularly use ul or demonstration o the bowel wall and anything projecting into it, or example, polyps. Polyps are projections o the bowel wall mucous membrane into the bowel lumen. Colitis is in ammation o the large bowel, o en associated with ulcerations o the mucosal wall. A single-contrast study most likely would obliterate these mucosal conditions, but coating o the bowel mucosa with barium and subsequent lling o the bowel with air (double contrast) provide optimal delineation. Single-contrast studies will demonstrate projections/ outpouchings rom the intestinal wall such as diverticulitis. 119. (C) Obtaining a complete and accurate history rom the patient or the radiologist is an important aspect o a radiographer’s job. Both subjective and objective data should be collected. Objective data include signs and symptoms that can be observed, such as a cough, a lump, or elevated blood pressure. Subjective data relate to what the patient eels and to what extent. A patient may experience pain, but is it mild or severe? Is it localized or general? Does the pain increase or decrease under di erent circumstances? A radiographer should explore this with the patient and document the in ormation on the requisition or the radiologist. 120. (D) Communication dif culties can arise with non–English-speaking patients. Most hospitals and large clinics have a list o resource people, automated systems, Language Lines, special dual headset phones, or similar accommodations to assist with interpretation when there is a language barrier. A certi ed interpreter is most help ul because he or she translates exactly what has been said—rather than a amily member or riend who might edit, or try to explain what he or she thinks is implied. People whose second language is English occasionally lose their ability to communicate in that second-language during times o trauma, illness, or stress. Volume, speed, and tone o voice may also be determined by culture. In addition, expressions/ gures o speech such as “a piece o cake” or “home ree” may not be understood by these patients or their amilies.

32

1: Patient Care and Education

121. (B) A patient who is going into shock may exhibit pallor and weakness, a signi cant drop in blood pressure, and an increased pulse. T e patient may also experience apprehension and restlessness and may have cool, clammy skin. A radiographer recognizing these symptoms should call them to the physician’s attention immediately. Fever is not associated with shock. 122. (D) Increased pain threshold, breakdown o skin, and atrophy o at pads and sweat glands are all important considerations when working with geriatric patients. Many changes occur as our bodies age. Although muscle is replaced with at, the amount o subcutaneous at is decreased, and the skin atrophies. T ere ore, the geriatric patient requires extragentle treatment. A mattress pad should always be placed on the radiographic table to help prevent skin injury or abrasions. I tape is required, paper tape should be used instead o adhesive tape. Geriatric patients are also more sensitive to hypothermia because o the breakdown o the sweat glands and always should be kept covered both to preserve modesty and or extra warmth. Loss o sensation in the skin increases pain tolerance, so the geriatric patient may not be aware o excessive stress on bony prominences such as the elbow, wrist, coccyx, and ankles. 123. (A) Antisepsis is the practice that retards the growth o pathogenic bacteria. Medical asepsis re ers to the destruction o pathogenic microorganisms through the process o disin ection. Examples o disin ectants include hydrogen peroxide, chlorine, and boric acid. Surgical asepsis (i.e., sterilization) re ers to the removal o all microorganisms and their spores (reproductive cells) and is practiced in the surgical suite. Healthcare practitioners must practice medical asepsis at all times. 124. (A) o obtain a diagnostic examination o the stomach, it must rst be empty. T e usual preparation is NPO (nothing by mouth) a er midnight (approximately 8 hours be ore the examination). Any material in the stomach can simulate the appearance o disease. 125. (D) Communication can be achieved in many orms; those orms can be verbal or nonverbal. E ective and pro essional patient communication skills are essential; the interaction between the

patient and radiographer generally leaves the patient with a lasting impression o his or her healthcare experience. T e radiographer’s communication skills must include a pro ciency in observational skills, listening skills, speaking skills, and writing skills. 126. (A) Creatinine is a normal alkaline constituent o urine and blood, but increased quantities o creatinine are present in advanced stages o renal disease. Creatinine and BUN blood chemistry levels should be checked prior to beginning an IVU. Increased levels may orecast an increased possibility o contrast media–induced renal e ects and poor visualization o the renal collecting systems. T e normal creatinine range is 0.6 to 1.5 mg/dL. T e normal BUN range is 8 to 20 mg/dL. 127. (C) A stethoscope and a sphygmomanometer are used together to measure blood pressure. T e rst sound heard is the systolic pressure, and the normal range is 110 to 140 mm Hg. When the sound is no longer heard, the diastolic pressure is recorded. T e normal diastolic range is 60 to 90 mm Hg. Elevated blood pressure is called hypertension. Hypotension, or low blood pressure, is not o concern unless it is caused by injury or disease; in that case, it can result in shock. A pulse oximeter is used to measure a patient’s pulse rate and oxygen saturation level. 128. (D) Diseases that are transmitted through the air include B, rubella (“German measles”), mumps, and in uenza. Airborne precautions require the patient to wear a string mask to avoid the spread o acid- ast bacilli (in the bronchial secretions o B patients) or other pathogens during coughing. I the patient is unable or unwilling to wear a mask, the radiographer must wear a mask to avoid the spread o acid- ast bacilli or other pathogens released during coughing. T e radiographer should wear gloves, but a gown is required only i agrant contamination is likely. Patients in ected with diseases calling or airborne precautions require a private, specially ventilated (negative-pressure) room. A private room is also indicated or all patients on droplet precautions, that is, with diseases that are transmitted via large droplets expelled rom the patient while speaking, sneezing, or coughing. T e pathogenic droplets can in ect others when they come in contact with the mouth or nasal mucosa or

Answers: 121–130

conjunctiva. Rubella (“German measles”), mumps, and inf uenza are among the diseases spread by droplet contact; a private room is required or the patient, and healthcare practitioners wear a string mask, and gown and gloves as needed. 129. (D) A special population that requires care ul consideration in the imaging department is our pediatric patients. Communication and care challenges can be quite di erent with children, depending on their age; they must be provided with a sa e environment and never le unattended. A neonate is usually described as a child rom birth to 28 days (i.e., newborn). Imaging procedures should be explained to the parent/guardian, i they are present. T e neonatal must be kept warm and sta must constantly be in attendance. In ant (up to 1 year) care includes minimizing separation anxiety by keeping in ant and parent(s) together, keeping a amiliar object or two (toy, blanket) with the

33

in ant, and limiting the number o sta present in the x-ray room. oddlers (1–2 years) should be spoken to at eye level; the radiographer should be cheer ul and unhurried. Preschoolers (3–5 years) bene t rom simple explanations. Be honest with school-age children (6–12 years), explain what you will be doing and let them help whenever possible. Adolescents (13–18 years) require privacy and modesty. Young adults are described as 19 to 45 years. 130. (B) racheostomy is the surgical opening o the trachea to provide and secure an open airway. A tracheostomy is o en per ormed in emergency situations when there is upper airway obstruction, that is, above the level o the larynx. Conditions requiring a tracheostomy include crushing injury o the tracheal rings, in amed and swollen tracheal mucous membranes, and aspiration o oreign body.

Subspecialty List

QUESTION NUMBER AND SUBSPECIALTY correspond to subcategories in each o the f ve ARRT examination specif cation sections 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 34

Medical emergencies In ection prevention and control Ethical and legal aspects Ethical and legal aspects Ethical and legal aspects Interpersonal communication Medical emergencies Interpersonal communication Pharmacology In ection prevention and control Contrast media Interpersonal communication In ection prevention and control Medical emergencies Pharmacology Medical emergencies Contrast media Medical emergencies Interpersonal communication Ethical and legal aspects Medical emergencies Ethical and legal aspects Pharmacology Ethical and legal aspects In ection prevention and control In ection prevention and control Medical emergencies In ection prevention and control Physical assistance and trans er Physical assistance and trans er Physical assistance and trans er

32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65. 66. 67.

Contrast media Physical assistance and trans er Ethical and legal aspects Ethical and legal aspects Physical assistance and trans er Interpersonal communication Interpersonal communication Pharmacology In ection prevention and control Physical assistance and trans er Interpersonal communication Ethical and legal aspects Contrast media Medical emergencies Ethical and legal aspects In ection prevention and control Ethical and legal aspects Interpersonal communication In ection prevention and control Ethical and legal aspects Physical assistance and trans er Physical assistance and trans er Physical assistance and trans er Physical assistance and trans er Medical emergencies Contrast media Interpersonal communication Pharmacology Ethical and legal aspects Physical assistance and trans er Contrast media In ection prevention and control Physical assistance and trans er Physical assistance and trans er In ection prevention and control Medical emergencies

Subspecialty List

68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 78. 79. 80. 81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92. 93. 94. 95. 96. 97. 98. 99.

In ection prevention and control Physical assistance and trans er Ethical and legal aspects In ection prevention and control Physical assistance and trans er Contrast media Physical assistance and trans er Medical emergencies Physical assistance and trans er Contrast media Physical assistance and trans er In ection prevention and control Medical emergencies Ethical and legal aspects Physical assistance and trans er In ection prevention and control Physical assistance and trans er Physical assistance and trans er Physical assistance and trans er Ethical and legal aspects Physical assistance and trans er Contrast media In ection prevention and control Physical assistance and trans er Physical assistance and trans er In ection prevention and control Physical assistance and trans er Ethical and legal aspects In ection prevention and control Ethical and legal aspects Physical assistance and trans er Physical assistance and trans er

Targeted Reading Adler AM, Carlton RR. Introduction to Radiologic Sciences and Patient Care. 5th ed. St. Louis, MO: Saunders Elsevier; 2012. ASR Code o Ethics. https://www.asrt.org/docs/practice-standards/codeo ethics.pd Frank ED, Long BW, Smith BJ. Merrill’s Atlas o Radiographic Positioning and Procedures. Bontrager KL, Lampignano JP. extbook o Radiographic Positioning and Related Anatomy. 8th ed. St Louis, MO: Mosby; 2014.

100. 101. 102. 103. 104. 105. 106. 107. 108. 109. 110. 111. 112. 113. 114. 115. 116. 117. 118. 119. 120. 121. 122. 123. 124. 125. 126. 127. 128. 129. 130.

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Physical assistance and trans er In ection prevention and control In ection prevention and control Contrast media Pharmacology Physical assistance and trans er Physical assistance and trans er Medical emergencies Physical assistance and trans er Physical assistance and trans er Pharmacology In ection prevention and control In ection prevention and control Contrast media Physical assistance and trans er Physical assistance and trans er Medical emergencies Ethical and legal aspects Contrast media Interpersonal communication Interpersonal communication Medical emergencies Physical assistance and trans er In ection prevention and control Physical assistance and trans er Interpersonal communication Physical assistance and trans er Physical assistance and trans er In ection prevention and control Interpersonal communication Physical assistance and trans er

Ehrlich RA, Coakes DM. Patient Care in Radiography. 8th ed. OSHA/latex,www. sbaa.org/at /c /%7B99DD789 C-904D467E-A2E4- DF1D36E381C0%7D/Latex_2006.pd Dutton AG, Linn-Watson A, orres LS. orres’ Patient Care in Imaging echnology. 8th ed. Philadelphia, PA: Lippincott; 2013. McConnell H. T e Nature o Disease, Pathology or the Health Pro essions. 2nd ed. Philadelphia, PA: Wolters Kluwer Lippincott Williams & Wilkins; 2014.

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CHAPTER 2

Imaging Procedures Questions

DIRECTIONS (Questions 1 through 300): Each of the numbered items or incomplete statements in this section is followed by answers or by completions of the statement. Select the one lettered answer or completion that is best in each case. 1. T e term valgus re ers to (A) (B) (C) (D)

turned outward turned inward rotated medially rotated laterally

2. Demonstration o the posterior at pad on the lateral projection o the adult elbow can be caused by 1. trauma or other pathology 2. greater than 90-degree exion 3. less than 90-degree exion (A) (B) (C) (D)

1 only 3 only 1 and 2 only 1 and 3 only

3. What is that portion o bone labeled C in the pediatric PA hand image seen in Figure 2-1 below? (A) (B) (C) (D)

A

Diaphysis Epiphysis Metaphysis Apophysis

B C

Figure 2-1.

4. T e proximal radius and ulna are seen ree o superimposition in the ollowing projection (A) (B) (C) (D)

Scapular Y AP scapula Medial oblique elbow Lateral oblique elbow

37

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2: Imaging Procedures

5. T e emale bony pelvis di ers rom the male bony pelvis in the ollowing way(s) 1. T e male greater/ alse pelvis is deep. 2. T e male acetabulum aces more laterally. 3. T e emale coccyx is more vertical. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

6. Which o the ollowing techniques would provide a posteroanterior (PA) projection o the gastroduodenal sur aces o a barium- lled high and transverse stomach? (A) Place the patient in a 35- to 40-degree right anterior oblique (RAO) position. (B) Place the patient in a lateral position. (C) Angle the CR 35 to 45 degrees cephalad. (D) Angle the CR 35 to 45 degrees caudad. 7. T e structures that would be visualized when obtained as positioned in Figure 2-2, could also be visualized when per ormed with the patient in the ollowing position 1. Lateral recumbent 2. Seated 3. Erect AP (A) (B) (C) (D)

8. All the ollowing statements regarding respiratory structures are true except (A) (B) (C) (D)

the le lung has two ssures. the in erior portion o a lung is its apex. each lung is enclosed in pleural membrane. the main stem bronchi enter the lung hilum.

9. All the ollowing statements regarding an exact PA projection o the skull are true except (A) (B) (C) (D)

the orbitomeatal line is perpendicular to the IR. the petrous pyramids ll the orbits. the midsagittal plane (MSP) is parallel to the IR. the central ray is perpendicular to the IR and exits at the nasion.

10. An accurate critique o the PA projection o the chest seen in Figure 2-3 would include the ollowing 1. T e pulmonary apices are demonstrated. 2. T e air- lled trachea and carina are demonstrated. 3. 10 posterior ribs are seen above the diaphragm. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Figure 2-2.

Figure 2-3.

Questions: 5–16

39

11. Pacemaker electrodes can be introduced through a vein in the chest or upper extremity, rom where they are advanced to the (A) (B) (C) (D)

le atrium right atrium le ventricle right ventricle

12. Flattening o the hemidiaphragms is characteristic o which o the ollowing conditions? (A) (B) (C) (D)

Pneumothorax Pleural e usion Emphysema Pneumonia

13. Structures located in the right lower quadrant (RLQ) include the ollowing 1. Cecum 2. Vermi orm appendix 3. Sigmoid (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

14. Which o the ollowing statements regarding Figure 2-4 is correct? (A) T e le kidney is more parallel to the IR. (B) T e image was made in the le posterior oblique position. (C) T e le ureter is better visualized. (D) T e image was made post-void.

Figure 2-4. Courtesy of Stamford Hospital, Department of Radiology.

15. During an upper gastrointestinal (GI) examination, a stomach o average shape demonstrates a barium- lled undus and double contrast o the pylorus and duodenal bulb. T e position used is most likely (A) (B) (C) (D)

AP erect PA RAO LPO

16. Which o the ollowing articulations participate(s) in ormation o the ankle mortise? 1. alotibial 2. alocalcaneal 3. alo bular (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 3 only

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2: Imaging Procedures

17. T e upper sur ace o the oot may be described as the 1. plantar sur ace 2. anterior sur ace 3. dorsum (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

22. Figure 2-5 demonstrates which o the ollowing conditions? (A) (B) (C) (D)

Right upper lobe atelectasis Le upper lobe atelectasis Pneumothorax Dextrocardia

L

18. T e outermost wall o the digestive tract is the (A) (B) (C) (D) 19.

mucosa muscularis submucosa serosa

erms used to describe movement include 1. Plantar exion 2. Valgus 3. Oblique (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

20. In the AP axial projection ( owne method) o the skull, with the CR directed 30 degrees caudad to the orbitomeatal line (OML) and passing midway between the external auditory meati, which o the ollowing is best demonstrated? (A) (B) (C) (D)

Occipital bone Frontal bone Facial bones Basal oramina

21. T e right posterior oblique position (Judet method) o the right acetabulum will demonstrate the 1. anterior rim o the right acetabulum 2. right iliac wing 3. right anterior iliopubic column (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Figure 2-5. Courtesy of Stamford Hospital, Department of Radiology.

23. A rontal view o the sternum is best accomplished in which o the ollowing positions? (A) (B) (C) (D)

AP PA RAO LAO

24. What is the name o the condition that results in the orward slipping o one vertebra on the one below it? (A) (B) (C) (D)

Spondylitis Spondylolysis Spondylolisthesis Spondylosis

Questions: 17–31

41

25. Which o the ollowing can be used to demonstrate the intercondyloid ossa? 1. Prone, knee exed 40 degrees, CR directed caudad 40 degrees to the popliteal ossa 2. Supine, IR under exed knee, CR directed cephalad to knee, perpendicular to tibia 3. Prone, patella parallel to IR, heel rotated 5 to 10 degrees lateral, CR perpendicular to knee joint (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

26. How should a chest examination to rule out air– uid levels be obtained on a patient with traumatic injuries? (A) Per orm the examination in the rendelenburg position. (B) Erect inspiration and expiration images should be obtained. (C) Include a lateral chest examination per ormed in dorsal decubitus position. (D) Per orm the examination AP supine at 44-in SID. 27. All the ollowing statements regarding the use o iodinated contrast agents with patients taking metormin hydrochloride are true except (A) met ormin is used to help lower blood sugar levels in type 2 diabetic patients (B) patients on met ormin who have intravenous (IV) iodinated contrast agent administration are at risk or renal ailure (C) met ormin should be withheld or 48 hours be ore IV iodinated contrast studies (D) met ormin should be withheld or 48 hours a er IV iodinated contrast studies 28. Which o the ollowing methods was used to obtain the image seen in Figure 2-6? (A) Erect PA, chin extended, OML orming 37 degrees to IR (B) Erect PA, OML, and CR perpendicular to IR (C) Erect PA, chin extended, OML 15 degrees rom horizontal (D) Erect PA, chin extended, OML 30 degrees rom horizontal

Figure 2-6. Courtesy of Stamford Hospital, Department of Radiology.

29. Which o the ollowing statements regarding the radiograph in Figure 2-6 is (are) true? 1. T e position is used to demonstrate the rontal and ethmoid sinuses. 2. T e ethmoid sinuses are seen near the medial aspect o the orbits. 3. T e perpendicular plate is visualized in midline o the nasal cavity. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

30. Which o the ollowing is an important consideration to avoid excessive metacarpophalangeal joint overlap in the oblique projection o the hand? (A) Oblique the hand no more than 45 degrees. (B) Use a support sponge or the phalanges. (C) Clench the st to bring the carpals closer to the IR. (D) Use ulnar exion. 31. Sternoclavicular articulations are likely to be demonstrated in all o the ollowing except (A) (B) (C) (D)

weight-bearing RAO LAO PA

42

2: Imaging Procedures

32. T e relationship between the ends o long bones is re erred to as (A) (B) (C) (D)

ractured

angulation apposition luxation sprain

1 2

33. Which o the ollowing positions is obtained with the patient lying supine on the radiographic table with the CR directed horizontally to the iliac crest? (A) (B) (C) (D)

Lateral decubitus, a ected side up Lateral decubitus, a ected side down AP rendelenburg AP supine

35. Which o the anatomic structures listed below is seen most anteriorly in a lateral projection o the chest? (A) Esophagus (B) rachea (C) Cardiac apex (D) Superimposed scapular borders 36. For an AP projection o the knee on a patient whose measurement rom ASIS to tabletop is 21 cm, which CR direction will best demonstrate the knee joint? (A) (B) (C) (D)

5 degrees caudad 10 degrees caudad 5 degrees cephalad 0 degree (perpendicular)

37. In which o the ollowing projections was the image in Figure 2-7 made? (A) (B) (C) (D)

4 5

Le lateral decubitus position Right lateral decubitus position Ventral decubitus position Dorsal decubitus position

34. Which o the ollowing positions is required to demonstrate small amounts o air in the peritoneal cavity? (A) (B) (C) (D)

3

AP Medial oblique Lateral oblique Acute exion

Figure 2-7. Courtesy of Stamford Hospital, Department of Radiology.

38. Which o the ollowing anatomic structures is indicated by the number 2 in Figure 2-7? (A) Medial epicondyle (B) rochlea (C) Capitulum (D) Olecranon process 39. Which o the ollowing is (are) well demonstrated in the lumbar spine pictured in Figure 2-8? 1. Zygpophyseal articulations 2. Intervertebral oramina 3. Pedicles (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Questions: 32–45

43

43. A lateral projection o the hand in extension is o en recommended to evaluate 1. a racture 2. a oreign body 3. so tissue (A) (B) (C) (D) L

44. Which o the ollowing positions is illustrated in Figure 2-9? (A) (B) (C) (D)

Figure 2-8. Courtesy of Stamford Hospital, Department of Radiology.

40. An intrathecal injection is associated with which o the ollowing examinations? (A) (B) (C) (D)

Intravenous urogram Retrograde pyelogram Myelogram Cystogram

41. Which o the ollowing projections can be used to supplement the traditional “open-mouth” projection when the upper portion o the odontoid process cannot be well demonstrated? (A) (B) (C) (D)

RPO LPO AP axial Right lateral decubitus

1 2

3

4 5 6

AP or PA through the oramen magnum AP oblique with right and le head rotation Horizontal beam lateral AP axial

42. T e oor o the cranium includes all the ollowing bones except (A) (B) (C) (D)

1 only 2 only 2 and 3 only 1 and 3 only

the temporal bones the occipital bone the ethmoid bone the sphenoid bone

Figure 2-9. Courtesy of Stamford Hospital, Department of Radiology.

45. T e cecum is labeled in Figure 2-9 as number (A) (B) (C) (D)

3 4 5 6

44

2: Imaging Procedures

46. T e condition that results rom a persistent connection between the etal aorta and pulmonary artery is (A) (B) (C) (D)

51. T e sternal angle is at approximately the same level as the

an atrial septal de ect a ventricular septal de ect a patent ductus arteriosus coarctation o the aorta

47. Which o the ollowing projections or positions will best demonstrate subacromial or subcoracoid dislocation?

(A) 2–3 interspace h thoracic vertebra (B) 9–10 interspace (C) 5 (D) costal margin 52. Which o the ollowing is a condition in which an occluded blood vessel stops blood ow to a portion o the lungs?

(A) angential (B) AP axial (C) ransthoracic lateral (D) PA oblique scapular Y 48. Arteries and veins enter and exit the medial aspect o each lung at the (A) (B) (C) (D)

root hilus carina epiglottis

49. Which o the ollowing positions can be used to demonstrate the axillary ribs o the right thorax?

(A) (B) (C) (D) 53.

Pneumothorax Atelectasis Pulmonary embolism Hypoxia

o demonstrate esophageal varices, the patient must be examined in (A) (B) (C) (D)

the recumbent position the erect position the anatomic position the Fowler position

54. Which o the ollowing statements regarding Figure 2-10 is (are) true?

1. RAO 2. LAO 3. RPO

1. Midphalanges are oreshortened. 2. T e degree o obliquity is too great. 3. Interphalangeal joints are well demonstrated.

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

50. In which projection o the oot are the interspaces between the rst and second cunei orms best demonstrated? (A) (B) (C) (D)

Lateral oblique oot Medial oblique oot Lateral oot Weight-bearing oot

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Questions: 46–59

45

58. What condition(s) is/are demonstrated in Figure 2-11? 1. Emphysema 2. Pneumothorax 3. Pleural E usion (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Figure 2-10. Courtesy of Stamford Hospital, Department of Radiology.

55. T e tissue that occupies the central cavity o the adult long bone body/sha is (A) (B) (C) (D)

red marrow yellow marrow endosteum cancellous tissue

56. All the ollowing structures are associated with the posterior emur except (A) (B) (C) (D)

popliteal sur ace intercondyloid ossa intertrochanteric line linea aspera

57. Which o the ollowing projections o the ankle would best demonstrate the mortise? (A) (B) (C) (D)

Medial oblique 15 to 20 degrees Lateral oblique 15 to 20 degrees Medial oblique 45 degrees Lateral oblique 45 degrees

Figure 2-11.

59. Which o the ollowing bony landmarks is in the same transverse plane as L2–3? (A) (B) (C) (D)

In erior costal margin Greater trochanter Iliac crest ASIS

46

2: Imaging Procedures

60. A radiolucent sponge can be placed under the patient’s waist or a lateral projection o the lumbosacral spine to 1. make the vertebral column parallel with the IR 2. place the intervertebral disk spaces perpendicular to the IR 3. decrease the amount o SR reaching the IR (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

61. Which o the ollowing may be used to evaluate the glenohumeral joint? 1. Scapular Y projection 2. In erosuperior axial 3. ransthoracic lateral (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

62. Which o the ollowing is (are) proximal to the tibial plateau? 1. Intercondyloid ossa 2. ibial condyles 3. ibial tuberosity (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

63. Evaluation criteria or a lateral projection o the humerus include 1. epicondyles parallel to the IR 2. lesser tubercle in pro le 3. superimposed epicondyles (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 1, 2, and 3

64. Which o the ollowing are mediastinal structures? 1. Heart 2. rachea 3. Esophagus (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

65. With the patient in the PA position, which o the ollowing tube angle and direction combinations is correct or an axial projection o the clavicle? (A) (B) (C) (D)

5 to 15 degrees caudad 5 to 15 degrees cephalad 15 to 30 degrees cephalad 15 to 30 degrees caudad

66. Which o the ollowing racture classi cations describes a small bony ragment pulled rom a bony process? (A) Avulsion racture (B) orus racture (C) Comminuted racture (D) Compound racture 67. What portion o the humerus articulates with the ulna to help orm the elbow joint? (A) Semilunar/trochlear notch (B) Radial head (C) Capitulum (D) rochlea 68. Movement o a part toward the midline o the body is termed (A) (B) (C) (D)

eversion inversion abduction adduction

69. During myelography, contrast medium is introduced into the (A) (B) (C) (D)

subdural space subarachnoid space epidural space epidermal space

Questions: 60–76

70. T e junction o the sagittal and coronal sutures is the (A) (B) (C) (D)

diploe lambda bregma pterion

71. Which o the ollowing statements is (are) true regarding the radiograph in Figure 2-12? 1. T e patient is placed in an RAO position. 2. T e midcoronal plane is about 60 degrees to the IR. 3. T e acromion process is ree o superimposition. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

47

72. Examples o synovial pivot articulations include the 1. atlantoaxial joint 2. radioulnar joint 3. temporomandibular joint (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3 only

73. T e lumbar vertebral lamina is represented by what part o the “Scotty dog” seen in a correctly positioned oblique lumbar spine? (A) (B) (C) (D)

Eye Nose Body Ear

74. An injury to a structure located on the side opposite that o the primary injury is re erred to as (A) (B) (C) (D)

blowout Le Fort contracture contrecoup

75. In which o the ollowing positions can the sesamoid bones o the oot be demonstrated to be ree o superimposition with the metatarsals or phalanges? (A) Dorsoplantar metatarsals/toes (B) angential metatarsals/toes (C) 30-degree medial oblique oot (D) 30-degree lateral oblique oot 76. Which o the ollowing conditions is limited speci cally to the tibial tuberosity? (A) (B) (C) (D)

Figure 2-12. Courtesy of Stamford Hospital, Department of Radiology.

Ewing sarcoma Osgood–Schlatter disease Gout Exostosis

48

2: Imaging Procedures

77. AP stress studies o the ankle may be per ormed 1. to demonstrate ractures o the distal tibia and bula 2. ollowing inversion or eversion injuries 3. to demonstrate a ligament tear (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

(A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

(A) (B) (C) (D)

right main stem bronchus le main stem bronchus esophagus proximal stomach

80. T e PA chest radiograph shown in Figure 2-13 demonstrates

78. Which o the ollowing is (are) part o the bony thorax? 1. Manubrium 2. Clavicles 3. 24 ribs

79. Aspirated oreign bodies in older children and adults are most likely to lodge in the

1. rotation 2. scapulae removed rom lung elds 3. adequate inspiration (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

81. T e letter A in Figure 2-13 indicates (A) (B) (C) (D)

a le anterior rib a right posterior rib a le posterior rib a right anterior rib

A

B

C

Figure 2-13. Courtesy of Stamford Hospital, Department of Radiology.

Questions: 77–88

82. With the patient seated at the end o the x-ray table, elbow exed 80 degrees, and the CR directed 45 degrees laterally rom the shoulder to the elbow joint, which o the ollowing structures will be demonstrated best? (A) (B) (C) (D)

Radial head Ulnar head Coronoid process Olecranon process

49

1 2 3 4

83. T e type(s) o articulations lacking a joint cavity include 1. Fibrous 2. Cartilaginous 3. Synovial (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

84. T e CR is parallel to the intervertebral oramina in the ollowing projection(s) 1. Lateral cervical spine 2. Lateral thoracic spine 3. Lateral lumbar spine (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

85. What structure is located midway between the anterosuperior iliac spine (ASIS) and pubic symphysis? (A) (B) (C) (D)

Dome o the acetabulum Femoral neck Greater trochanter Iliac crest

86. T e structure labeled 2 in Figure 2-14 is the (A) (B) (C) (D)

maxillary sinus sphenoidal sinus ethmoidal sinus rontal sinus

Figure 2-14.

87. Which o the ollowing would best evaluate the structure labeled 3 in Figure 2-14? (A) (B) (C) (D)

PA axial projection (Caldwell method) Parietoacanthial projection (Waters’ method) Lateral projection Submentovertex projection

88. Hysterosalpingography may be per ormed demonstration o 1. uterine tubal patency 2. mass lesions in the uterine cavity 3. uterine position (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

or

50

2: Imaging Procedures

89. T e radiograph shown in Figure 2-15 demonstrates the articulation between the

11

(A) (B) (C) (D)

8

12

1. talus and the calcaneus 2. calcaneus and the cuboid 3. talus and the navicular

7 9 10

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

5

6

1 2 3

4

Figure 2-16. Reproduced with permission from DA Saia. LANGE Radiography Review Flashcards. New York: McGraw-Hill; 2015.

91. T e articular acets o L5–S1 are best demonstrated in a(n) (A) (B) (C) (D)

AP projection 30-degree oblique 45-degree oblique AP axial projection

92. T e patient’s chin should be elevated during chest radiography to Figure 2-15. Courtesy of Stamford Hospital, Department of Radiology.

90. Identi y the structure labeled number 10 in the AP projection o the orearm shown in Figure 2-16 (A) (B) (C) (D)

Head o radius Head o ulna Radial styloid process Ulnar styloid process

(A) permit the diaphragm to move to its lowest position (B) avoid superimposition on the apices (C) assist in maintaining an upright position (D) keep the MSP parallel 93. T e secondary center o ossi cation in long bones is the (A) (B) (C) (D)

diaphysis epiphysis metaphysis apophysis

Questions: 89–100

94. Medial displacement o a tibial racture would be best demonstrated in the (A) (B) (C) (D)

AP projection lateral projection medial oblique projection lateral oblique projection

95. T e lumbar transverse process is represented by what part o the “Scotty dog” seen in a correctly positioned oblique lumbar spine view? (A) (B) (C) (D)

Eye Nose Body Neck

98. At what level do the carotid arteries bi urcate? (A) Foramen magnum (B) rachea (C) Pharynx (D) C4 99. During a double-contrast BE, which o the ollowing positions would a ord the best double-contrast visualization o the lateral wall o the descending colon and the medial wall o the ascending colon? (A) (B) (C) (D)

96. All the ollowing statements regarding the position shown in Figure 2-17 are true except (A) a le pleural e usion could be demonstrated. (B) a right pneumothorax could be demonstrated. (C) a le lateral decubitus position is illustrated. (D) the CR is directed vertically to the level o 7.

51

AP or PA erect Right lateral decubitus Le lateral decubitus Ventral decubitus

100. Which o the ollowing statements is/are true regarding the shoulder image seen in Figure 2-18? 1. T e una ected arm is adjacent to the IR. 2. It provides a lateral view. 3. It is requently per ormed in trauma situations. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Figure 2-17.

97. Which o the ollowing positions would best demonstrate the proximal tibio bular articulation? (A) (B) (C) (D)

AP 90 degrees mediolateral 45-degree internal rotation 45-degree external rotation

Figure 2-18. Reproduced with permission from DA Saia. LANGE Radiography Review Flashcards. New York: McGraw-Hill; 2015.

52

2: Imaging Procedures

101. Elements o correct positioning or PA projection o the chest include

105. In a lateral projection o the normal knee, the

1. Weight evenly distributed on eet 2. Elevation o the chin 3. Shoulders elevated and rolled orward

1. bular head should be somewhat superimposed on the proximal tibia 2. patello emoral joint should be visualized 3. emoral condyles should be superimposed

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

102. Which o the ollowing conditions is o en the result o ureteral obstruction or stricture? (A) (B) (C) (D)

Pyelonephrosis Nephroptosis Hydronephrosis Cystourethritis

103. Important considerations or radiographic examinations o traumatic injuries to the upper extremity include 1. the joint closest to the injured site should be supported during movement o the limb 2. both joints must be included in long bone studies 3. two views, at 90 degrees to each other, are required (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

104. All the ollowing statements regarding large bowel radiography are true except (A) the large bowel must be completely empty prior to examination. (B) retained ecal material can obscure pathology. (C) single-contrast studies help to demonstrate intraluminal lesions. (D) double-contrast studies help to demonstrate mucosal lesions.

1 only 2 only 1 and 3 only 1, 2, and 3

106. All elbow at pads are best demonstrated in which position? (A) (B) (C) (D)

AP Lateral Acute exion AP partial exion

107. T e term used to describe the presence o blood in vomit is (A) hemoptysis (B) hematemesis (C) chronic obstructive pulmonary disease (COPD) (D) bronchitis 108. Double-contrast examinations o the stomach or large bowel are per ormed to better visualize the (A) (B) (C) (D)

position o the organ size and shape o the organ diverticula gastric or bowel mucosa

109. Which position o the shoulder demonstrates the lesser tubercle in pro le medially? (A) (B) (C) (D)

AP External rotation Internal rotation Neutral position

Questions: 101–113

53

110. In the PA projection o the hand seen in Figure 2-19, which numeral identi es the proximal interphalangeal joint? (A) (B) (C) (D)

4 5 6 7

Figure 2-20.

7 6

113. Which o the ollowing structures is illustrated by the number 2 in Figure 2-21? (A) (B) (C) (D)

5 4

Maxillary sinus Coronoid process Zygomatic arch Coracoid process

3 2 1

R

Figure 2-19.

111. In which position o the shoulder is the greater tubercle seen superimposed on the humeral head? (A) (B) (C) (D)

AP External rotation Internal rotation Neutral position

112. With the patient positioned as illustrated in Figure 2-20, which o the ollowing structures is best demonstrated? (A) Patella (B) Patello emoral articulation (C) Intercondyloid ossa (D) ibial tuberosity

Figure 2-21. Courtesy of Stamford Hospital, Department of Radiology.

54

2: Imaging Procedures

114. Which o the ollowing articulations may be described as diarthrotic?

117. Structures comprising the neural, or vertebral, arch include

1. Condyloid 2. Sellar 3. Gomphosis

1. pedicles 2. laminae 3. body

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 3 only 1 and 2 only 1, 2, and 3

115. Ulnar exion/deviation will best demonstrate which carpal(s)?

118. In which type o racture are the splintered ends o bone orced through the skin?

1. Medial carpals 2. Lateral carpals 3. Scaphoid (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

(A) (B) (C) (D)

Use a perpendicular CR. Angle the CR about 30 degrees cephalad. Angle the CR about 30 degrees caudad. Angle the MSP 15 degrees toward the a ected side.

Closed Compound Compression Depressed

119. T e thoracic zygapophyseal joints are demonstrated with the (A) (B) (C) (D)

116. What should be done to better demonstrate the coracoid process shown in Figure 2-22? (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

120.

coronal plane 90 degrees to the IR. midsagittal plane 90 degrees to the IR. coronal plane 20 degrees to the IR. midsagittal plane 20 degrees to the IR.

o reduce the amount o scattered radiation reaching the IR in CR/DR imaging o the lumbosacral region, which o the ollowing is (are) recommended? 1. Close collimation 2. Lead mat on table posterior to the patient 3. Decreased SID (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

121. T e long, at structures that project posteromedially rom the pedicles are the (A) (B) (C) (D) Figure 2-22. Courtesy of Stamford Hospital, Department of Radiology.

transverse processes vertebral arches laminae pedicles

Questions: 114–127

122. T e type o ileus characterized by cessation o peristalsis is termed (A) (B) (C) (D)

125. Which o the ollowing statements is (are) correct with respect to the images shown in Figure 2-23? 1. Image A was made with cephalad angulation. 2. Image B was made with cephalad angulation. 3. Images A and B were made with CR directed 15 degrees cephalad.

mechanical paralytic asymptomatic sterile

(A) (B) (C) (D)

123. T e projection/method o en used to detect carpal canal de ect is (A) PA projection wrist, radial deviation (B) PA axial projection wrist, Stecher method (C) AP oblique hands/Norgaard Method (D) angential projection wrist, Gaynor-Hart method

AP projection lateral projection axial projection lordotic projection

(A) (B) (C) (D)

asthenic hyposthenic sthenic hypersthenic

127. Which o the ollowing should be per ormed to rule out subluxation or racture o the cervical spine? (A) (B) (C) (D)

A

1 only 2 only 2 and 3 only 1, 2, and 3

126. T e body habitus having short and wide heart and lung area and a high transverse stomach is the

124. Narrowing o the upper airway, as seen in pediatric croup, can be best visualized in the (A) (B) (C) (D)

55

Oblique cervical spine, seated AP cervical spine, recumbent Horizontal beam lateral Laterals in exion and extension

B

Figure 2-23. A and B: Courtesy of Stamford Hospital, Department of Radiology.

56

2: Imaging Procedures

128. Which o the ollowing is proximal to the carpal bones? (A) (B) (C) (D)

133. During IV urography, the prone position generally is recommended to demonstrate 1. the lling o the ureters 2. the renal pelvis 3. the superior calyces

Distal interphalangeal joints Proximal interphalangeal joints Metacarpals Radial styloid process

(A) (B) (C) (D)

129. Which o the ollowing statements regarding the scapular Y projection o the shoulder is (are) true? 1. T e midsagittal plane should be about 60 degrees to the IR. 2. T e scapular borders should be superimposed on the humeral sha . 3. An oblique projection o the shoulder is obtained. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

130. Which o the ollowing positions will demonstrate the lumbosacral zygapophyseal articulation? (A) (B) (C) (D)

AP Lateral 30-degree RPO 45-degree LPO

131. T e most proximal portion o the pharynx is the (A) (B) (C) (D)

laryngopharynx nasopharynx epiglottis oropharynx

132. With the patient’s head in a PA position and the CR directed 20 degrees cephalad, which part o the mandible will be best visualized? (A) (B) (C) (D)

Symphysis Rami Body Angle

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

134. T e plane that passes vertically through the body, dividing it into anterior and posterior halves, is termed the (A) (B) (C) (D) 135.

median sagittal plane (MSP) midcoronal plane sagittal plane transverse plane

o demonstrate a pro le view o the glenoid ossa, the patient is AP recumbent and obliqued 45 degrees (A) toward the a ected side (B) away rom the a ected side (C) with the arm at the side in the anatomic position (D) with the arm in external rotation

136. T e number 2 in Figure 2-24 indicates the ollowing (A) Body o L2 (B) Spinous process o L1 (C) Spinous process o L3 (D) ransverse process o L3 137. During an air-contrast BE, in what part o the colon is air most likely to be visualized with the body in the AP recumbent position? (A) ransverse colon (B) Descending colon (C) Ascending colon (D) Le and right colic exures

Questions: 128–143

57

140. Valid evaluation criteria or a lateral projection o the orearm requires that 1. the epicondyles be parallel to the IR 2. the radius and ulna be superimposed distally 3. the radial tuberosity should ace anteriorly 1 5

2

3

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

4

141. Which o the ollowing positions will provide an AP projection o the L5–S1 interspace? (A) Patient AP with 30- to 35-degree angle cephalad (B) Patient AP with 30- to 35-degree angle caudad (C) Patient AP with 0-degree angle (D) Patient lateral, coned to L5 Figure 2-24. Reproduced with permission from DA Saia. LANGE Radiography Review Flashcards. New York: McGraw-Hill; 2015.

138. Central ray angulation may be required or 1. magni cation o anatomic structures 2. oreshortening or sel -superimposition 3. superimposition o overlying structures (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

139. Which o the ollowing is recommended to better demonstrate the tarsometatarsal joints in a dorsoplantar projection o the oot? (A) (B) (C) (D)

Invert the oot Evert the oot Angle the CR 10 degrees posteriorly Angle the CR 10 degrees anteriorly

142. Subject/object unsharpness can result rom all o the ollowing except when (A) object shape does not coincide with the shape o x-ray beam (B) object plane is not parallel with x-ray tube and/or IR (C) anatomic object(s) o interest is/are in the path o the CR (D) anatomic object(s) o interest is/are at a distance rom the IR 143. Patients are instructed to remove all jewelry, hair clips, metal prostheses, coins, and credit cards be ore entering the room or an examination in (A) (B) (C) (D)

sonography computed tomography (C ) magnetic resonance imaging (MRI) nuclear medicine

58

2: Imaging Procedures

144. T e true lateral position o the skull uses which o the ollowing principles?

146. A kyphotic curve is ormed by which o the ollowing?

1. Interpupillary line perpendicular to the IR 2. MSP perpendicular to the IR 3. In raorbitomeatal line (IOML) parallel to the transverse axis o the IR (A) (B) (C) (D)

1. Sacral vertebrae 2. T oracic vertebrae 3. Lumbar vertebrae (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3 147.

145. In which o the ollowing positions was the radiograph shown in Figure 2-25 probably made? (A) (B) (C) (D)

Supine recumbent Prone recumbent PA upright Supine rendelenburg

1 only 1 and 2 only 3 only 1 and 3 only

o evaluate the interphalangeal joints in the oblique and lateral positions, the ngers (A) (B) (C) (D)

rest on the IR or immobilization must be supported parallel to the IR are radiographed in natural exion are radiographed in palmar exion

148. T e ossi ed portion o a long bone where cartilage has been replaced by bone is known as the (A) (B) (C) (D)

diaphysis epiphysis metaphysis apophysis

149. Which o the ollowing positions will most e ectively move the gallbladder away rom the vertebrae in an asthenic patient? (A) (B) (C) (D)

LAO RAO LPO Erect

150. T e ileocecal valve normally is located in which o the ollowing body regions?

Figure 2-25. Courtesy of Stamford Hospital, Department of Radiology.

(A) (B) (C) (D)

Right iliac Le iliac Right lumbar Hypogastric

Questions: 144–155

151. Which o the ollowing is (are) true regarding radiographic examination o the acromioclavicular joints?

59

155. Which o the ollowing statements is (are) true with respect to the radiograph shown in Figure 2-26?

1. T e procedure is per ormed in the erect position. 2. Use o weights can improve demonstration o the joints. 3. T e procedure should be avoided i dislocation or separation is suspected.

1. T e acromion process is seen partially superimposed on the third rib. 2. T is projection is per ormed to evaluate the scapula. 3. T is projection is per ormed to evaluate the acromioclavicular articulation.

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 2 and 3 only

1 only 2 only 1 and 2 only 2 and 3 only

152. A type o cancerous bone tumor occurring in children and young adults and arising rom bone marrow is (A) (B) (C) (D)

Ewing sarcoma multiple myeloma enchondroma osteochondroma

153. With the patient recumbent on the x-ray table with the head lower than the eet, the patient is said to be in the (A) rendelenburg position (B) Fowler position (C) decubitus position (D) Sims position 154. Which o the ollowing skull positions will demonstrate the cranial base, sphenoidal sinuses, atlas, and odontoid process? (A) (B) (C) (D)

AP axial Lateral Parietoacanthial Submentovertical (SMV)

Figure 2-26. Courtesy of Stamford Hospital, Department of Radiology.

60

2: Imaging Procedures

156. Which o the ollowing is (are) located on the anterior aspect o the emur? 1. Patellar sur ace 2. Intertrochanteric crest 3. Linea aspera (A) (B) (C) (D)

1. Sternal extremities o clavicles are equidistant rom vertebral borders. 2. en posterior ribs are demonstrated above the diaphragm. 3. T e esophagus is visible in the midline.

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

157. In which o the ollowing tangential axial projections o the patella is complete relaxation o the quadriceps emoris required or an accurate diagnosis? 1. Supine exion 45 degrees (Merchant) 2. Prone exion 90 degrees (Settegast) 3. Prone exion 55 degrees (Hughston) (A) (B) (C) (D)

(A) Neck o rib (B) ubercle o rib (C) ransverse process (D) Head o rib

1. talotibial joint is visualized. 2. talo bular joint is visualized. 3. tibia and bula are superimposed. 1 only 1 and 2 only 1 and 3 only 1, 2, and 3

1. supine and the CR angled 30 degrees caudad. 2. supine and the CR angled 30 degrees cephalad. 3. prone and the CR angled 30 degrees cephalad. 3 4 5 6 7

Figure 2-27.

Dorsoplantar projection o the oot Plantodorsal projection o the os calcis Medial oblique position o the oot Lateral oot

162. T e position illustrated in the radiograph in Figure 2-28 may be obtained with the patient 2

11

160. In which o the ollowing positions/projections will the talocalcaneal joint be visualized?

(A) (B) (C) (D)

1

10

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

161. In the lateral projection o the ankle, the

158. In Figure 2-27, the structure indicated as number 7 is which o the ollowing?

9

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3 only

8

159. Which o the ollowing statements is (are) correct with respect to evaluation criteria or a PA projection o the chest or lungs?

(A) (B) (C) (D)

1 only 2 only 1 and 3 only 2 and 3 only

Questions: 156–167

61

165. During atrial systole, blood ows into the 1. right ventricle via the mitral valve 2. le ventricle via the bicuspid valve 3. right ventricle via the tricuspid valve (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

166. T e scapula shown in Figure 2-29 demonstrates 1. its posterior aspect 2. its costal sur ace 3. its sternal articular sur ace (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3 1

Figure 2-28. Courtesy of Stamford Hospital, Department of Radiology.

(A) (B) (C) (D)

lateral rectum AP axial rectosigmoid right and le lateral decubitus abdomen RAO and LAO abdomen

164. Which o the ollowing statements regarding the Norgaard method, “Ball-Catcher’s position,” is (are) correct?

11

4 10

6

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

5

7

9

1. Bilateral AP oblique hands are obtained. 2. It is used or early detection o rheumatoid arthritis. 3. T e hands are obliqued about 45 degrees, palm up. (A) (B) (C) (D)

3

13

12

163. All the ollowing positions are likely to be employed or both single- and double-contrast examinations o the large bowel except

2

8

Figure 2-29.

167. In Figure 2-29, which o the ollowing is represented by the number 2? (A) (B) (C) (D)

Acromion process Scapular spine Coracoid process Acromioclavicular joint

62

2: Imaging Procedures

168. In Figure 2-29, which o the ollowing is represented by the number 9? (A) (B) (C) (D)

Medial border Lateral border In erior angle Superior angle

169. With the patient in the PA position and the OML and CR perpendicular to the IR, the resulting radiograph will demonstrate the petrous pyramids (A) (B) (C) (D)

below the orbits in the lower third o the orbits completely within the orbits above the orbits

173. What is the position o the stomach in a hypersthenic patient? (A) (B) (C) (D)

High and vertical High and horizontal Low and vertical Low and horizontal

174. In the anterior oblique position o the cervical spine, the structures best seen are the (A) (B) (C) (D)

intervertebral oramina nearest the IR intervertebral oramina urthest rom the IR interarticular joints intervertebral joints

175. During chest radiography, the act o inspiration 170. When evaluating a PA axial projection o the skull with a 15-degree caudal angle, the radiographer should see 1. petrous pyramids in the lower third o the orbits 2. equal distance rom the lateral border o the skull to the lateral rim o the orbit bilaterally 3. symmetrical petrous pyramids (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

171. Which o the ollowing barium- lled anatomic structures is best demonstrated in the LPO position? (A) (B) (C) (D)

Hepatic exure Splenic exure Sigmoid colon Ileocecal valve

172. T e uppermost portion o the iliac crest is at approximately the same level as the (A) (B) (C) (D)

costal margin umbilicus xiphoid tip ourth lumbar vertebra

1. elevates the diaphragm 2. raises the ribs 3. depresses the abdominal viscera (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

176. In the lateral projection o the scapula, the 1. vertebral and axillary borders are superimposed. 2. acromion and coracoid processes are superimposed. 3. in erior angle is superimposed on the ribs. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

177. Which o the ollowing statements is (are) true regarding Figure 2-30? 1. T e image was made in the RAO position. 2. Exposure was made during shallow respiration. 3. T e sternum is projected onto the le side o the thorax. (A) (B) (C) (D)

1 only 2 only 2 and 3 only 1, 2, and 3

Questions: 168–183

63

179. Which o the ollowing is (are) demonstrated in an AP axial projection o the cervical spine? 1. C3–7 cervical bodies 2. Intervertebral oramina 3. Zygpophyseal joints (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

180. With which o the ollowing does the trapezium articulate? (A) (B) (C) (D) Figure 2-30. Reproduced with permission from David Sack, B.S., R.T. (R), CRA, FAHRA.

178.

Fi h metacarpal First metacarpal Distal radius Distal ulna

181. Which o the ollowing statements is (are) true regarding a PA projection o the paranasal sinuses? 1. T e OML is elevated 15 degrees rom the horizontal. 2. T e petrous pyramids completely ll the orbits. 3. T e rontal and ethmoidal sinuses are visualized.

o better visualize the knee-joint space in the radiograph in Figure 2-31, the radiographer should (A) ex the knee more acutely (B) ex the knee less acutely (C) angle the CR 5 to 7 degrees cephalad (D) angle the CR 5 to 7 degrees caudad

(A) (B) (C) (D) 182.

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

racheotomy is an e ective technique used to restore breathing when there is (A) respiratory pathway obstruction above the larynx (B) crushed tracheal rings owing to trauma. (C) respiratory pathway closure owing to in ammation and swelling (D) all the above

183. During GI radiography, the position o the stomach may vary depending on 1. the respiratory phase 2. body habitus 3. patient position

Figure 2-31. Courtesy of Stamford Hospital, Department of Radiology.

(A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

64

2: Imaging Procedures

184. For which o the ollowing conditions is operative cholangiography a use ul tool? 1. Patency o the biliary ducts 2. Biliary tract calculi 3. Duodenal calculi (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

185. For the average patient, the CR or a lateral projection o a barium- lled stomach should enter (A) midway between the midcoronal line and the anterior abdominal sur ace (B) midway between the vertebral column and the lateral border o the abdomen (C) at the midcoronal line at the level o the iliac crest (D) perpendicular to the level o L2

188. Which o the ollowing positions is used to demonstrate vertical patellar ractures and the patello emoral articulation? (A) AP knee (B) Lateral knee (C) angential patella (D) unnel view 189. T e structure labeled 3 in Figure 2-32 is the (A) (B) (C) (D)

spinous process o C2 body o C2 body o C1 posterior arch o C1

3 4 6

186. When examining a patient whose elbow is in partial exion, how should an AP projection be obtained?

5

1

2

1. With humerus parallel to IR, CR perpendicular 2. With orearm parallel to IR, CR perpendicular 3. T rough the partially exed elbow, resting on the olecranon process, CR perpendicular (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

187. Which o the ollowing is (are) appropriate technique(s) or imaging a patient with a possible traumatic spine injury? 1. Instruct the patient to turn slowly and stop i anything hurts. 2. Maneuver the x-ray tube instead o moving the patient. 3. Call or help and use the log-rolling method to turn the patient. (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

Figure 2-32. Courtesy of Stamford Hospital, Department of Radiology.

190. T e structure labeled 1 in Figure 2-32 is the (A) (B) (C) (D)

Zygapophyseal joint Intervertebral oramen Intervertebral disc space Vertebral body

Questions: 184–200

191. Which o the ollowing examinations is used to demonstrate vesicoureteral re ux? (A) (B) (C) (D)

Retrograde urogram Intravenous urogram (IVU) Voiding cystourethrogram Retrograde cystogram

192. Which o the ollowing should be demonstrated in a true AP projection o the clavicle? 1. Clavicular body 2. Acromioclavicular joint 3. Sternocostal joint (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

193. In which o the ollowing projections is the talo bular joint best demonstrated? (A) (B) (C) (D)

AP Lateral oblique Medial oblique Lateral

194. Free air in the abdominal cavity is best demonstrated in which o the ollowing positions? (A) AP projection, le lateral decubitus position (B) AP projection, right lateral decubitus position (C) PA recumbent position (D) AP recumbent position 195. Which o the ollowing sequences correctly describes the path o blood ow as it leaves the le ventricle? (A) (B) (C) (D)

Arteries, arterioles, capillaries, venules, veins Arterioles, arteries, capillaries, veins, venules Veins, venules, capillaries, arteries, arterioles Venules, veins, capillaries, arterioles, arteries

65

196. Which o the ollowing projections o the elbow will demonstrate the radial head ree o ulnar superimposition? (A) (B) (C) (D)

AP Lateral Medial oblique Lateral oblique

197. An acromioclavicular separation will be best demonstrated in the ollowing projection (A) (B) (C) (D)

AP recumbent, a ected shoulder AP recumbent, both shoulders AP erect, a ected shoulder AP erect, both shoulders

198. Which o the ollowing statements regarding myelography is (are) correct? 1. Spinal puncture may be per ormed in the prone or exed lateral position. 2. Contrast medium distribution is regulated through x-ray tube angulation. 3. T e patient’s neck must be in extension during rendelenburg positions. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

199. Which o the ollowing is a major cause o bowel obstruction in children? (A) (B) (C) (D)

Appendicitis Intussusception Regional enteritis Ulcerative colitis

200. With the patient PA, the MSP centered to the grid, the OML orming a 37-degree angle with the IR, and the CR perpendicular and exiting the acanthion, which o the ollowing is best demonstrated? (A) (B) (C) (D)

Occipital bone Frontal bone Facial bones Basal oramina

66

2: Imaging Procedures

201. T e inhalation o liquid or solid particles into the nose, throat, or lungs is re erred to as (A) (B) (C) (D)

asphyxia aspiration atelectasis asystole

202. Endoscopic retrograde cholangiopancreatography (ERCP) usually involves 1. cannulation o the hepatopancreatic ampulla 2. introduction o contrast medium into the common bile duct 3. introduction o barium directly into the duodenum (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

203. Which o the ollowing is (are) associated with a Colles’ racture? 1. ransverse racture o the radial head 2. Chip racture o the ulnar styloid 3. Posterior or backward displacement (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 1, 2, and 3

204. T e axiolateral, or horizontal beam, projection o the hip requires the IR to be placed 1. parallel to the central ray (CR) 2. parallel to the long axis o the emoral neck 3. in contact with the lateral sur ace o the body (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

205. Which o the ollowing guidelines should be ollowed when per orming radiographic examinations on pediatric patients? (A) (B) (C) (D)

Use restraint only when necessary. Always use physical or mechanical restraint. Use physical restraint only. Use mechanical restraint only.

206. Which o the ollowing interventional procedures can be used to increase the diameter o a stenosed vessel? 1. Percutaneous transluminal angioplasty (P A) 2. Stent placement 3. Peripherally inserted central catheter (PICC line) (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

207. Which o the ollowing examinations involves the introduction o a radiopaque contrast medium through a uterine cannula? (A) (B) (C) (D)

Retrograde pyelogram Voiding cystourethrogram Hysterosalpingogram Myelogram

208. Correct preparation or a patient scheduled or an upper gastrointestinal (GI) series is most likely to be (A) iodinated contrast administration evening be ore examination; water only in the morning (B) NPO a er midnight (C) cathartics and cleansing enemas (D) NPO a er midnight, cleansing enemas, and empty bladder be ore scout image 209. T e contraction and expansion o arterial walls in accordance with orce ul contraction and relaxation o the heart are called (A) (B) (C) (D)

hypertension elasticity pulse pressure

Questions: 201–218

210. Which o the ollowing structures should be visualized through the oramen magnum in an AP axial projection ( owne method) o the skull or occipital bone?

67

215. T e AP projection o the coccyx requires that the CR be directed

1. Posterior clinoid processes 2. Dorsum sella 3. Posterior arch o C1

1. 15 degrees cephalad 2. 2 inches superior to the pubic symphysis 3. to a level midway between the ASIS and pubic symphysis

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 2 only 1 and 2 only 2 and 3 only

211. Which o the ollowing positions would be the best choice or a right shoulder examination to rule out racture? (A) (B) (C) (D)

Internal and external rotation AP and tangential AP and AP axial AP and scapular Y

212. Which o the ollowing projections will best demonstrate the tarsal navicular with minimal superimposition? (A) (B) (C) (D)

AP oblique, medial rotation AP oblique, lateral rotation Mediolateral Lateral weight-bearing

213. Which o the ollowing bones participate(s) in the ormation o the obturator oramen? 1. Ilium 2. Ischium 3. Pubis (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

214. Which o the ollowing radiologic procedures requires that a contrast medium be injected into the renal pelvis via a catheter placed within the ureter? (A) (B) (C) (D)

Nephrotomography Retrograde urography Cystourethrography IVU

1 only 2 only 1 and 2 only 1 and 3 only

216. Which o the ollowing views would best demonstrate arthritic changes in the knees? (A) (B) (C) (D)

AP recumbent Lateral recumbent AP erect Medial oblique

217. Which o the ollowing are characteristics o the hypersthenic body type? 1. Short, wide, transverse heart 2. High and peripheral large bowel 3. Diaphragm positioned low (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

218. Which o the ollowing statements is (are) true regarding the images shown in Figure 2-33? 1. Image A is positioned in internal rotation. 2. Image B is positioned in internal rotation. 3. T e greater tubercle is better demonstrated in image A. (A) (B) (C) (D)

1 only 2 only 1 and 3 only 2 and 3 only

68

2: Imaging Procedures

B

A

Figure 2-33. A and B. Courtesy of Stamford Hospital, Department of Radiology.

219. Which o the ollowing will best demonstrate the size and shape o the liver and kidneys? (A) (B) (C) (D)

Lateral abdomen AP abdomen Dorsal decubitus abdomen Ventral decubitus abdomen

220. Correct preparation or a patient scheduled or a lower GI series is most likely to be (A) iodinated contrast evening be ore examination; water only in the morning (B) NPO a er midnight (C) cathartics and cleansing enemas (D) NPO a er midnight, cleansing enemas, and empty bladder be ore scout image 221. In the AP axial projection, or bilateral “ rog-leg” position, which o the ollowing is most likely to place the long axes o the emoral necks parallel with the plane o the IR? (A) (B) (C) (D)

adducted 25 degrees abducted 25 degrees adducted 40 degrees abducted 40 degrees

rom the horizontal rom the vertical rom the horizontal rom the vertical

222. Which o the ollowing precautions should be observed when radiographing a patient who has sustained a traumatic injury to the hip? 1. When a racture is suspected, manipulation o the a ected extremity should be per ormed by a physician. 2. T e AP axiolateral projection should be avoided. 3. o evaluate the entire region, the pelvis typically is included in the initial examination. (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 1, 2, and 3

223. Which o the ollowing projections require(s) that the humeral epicondyles be perpendicular to the IR? 1. AP humerus 2. Lateral orearm 3. Internal rotation shoulder (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Questions: 219–231

224. Prior to the start o an IVU, which o the ollowing procedures should be carried out? 1. Have patient empty the bladder. 2. Review the patient’s allergy history. 3. Check the patient’s creatinine level. (A) (B) (C) (D) 225.

1 only 2 only 1 and 2 only 1, 2, and 3

o demonstrate the entire circum erence o the radial head, exposure(s) must be made with the 1. epicondyles perpendicular to the IR 2. hand pronated and supinated as much as possible 3. hand lateral and in internal rotation (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

226. T e image shown in Figure 2-34 was made in what position? (A) (B) (C) (D)

AP or PA erect Dorsal decubitus Le lateral decubitus Right lateral decubitus

227. In myelography, the contrast medium generally is injected into the (A) cisterna magna (B) individual intervertebral disks (C) subarachnoid space between the rst and second lumbar vertebrae (D) subarachnoid space between the third and ourth lumbar vertebrae 228. Which o the ollowing is (are) required or a lateral projection o the skull? 1. T e IOML is parallel to the IR. 2. T e MSP is parallel to the IR. 3. T e CR enters 3⁄4 inch superior and anterior to the EAM. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

229. Which o the ollowing is (are) e ective in reducing exposure to sensitive tissues or rontal views during scoliosis examinations? 1. Use o PA position 2. Use o breast shields 3. Use o compensating ltration (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

230. Which type o arthrography? (A) (B) (C) (D)

articulation is evaluated in

Synarthrodial Diarthrodial Amphiarthrodial Cartilaginous

231. T e laryngeal prominence is ormed by the

Figure 2-34. Courtesy of Stamford Hospital, Department of Radiology.

69

(A) (B) (C) (D)

thyroid gland thyroid cartilage vocal cords pharynx

70

2: Imaging Procedures

232. In the AP projection o the ankle, the 1. plantar sur ace o the oot is vertical 2. bula projects more distally than the tibia 3. calcaneus is well visualized (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

233. Which o the ollowing examinations most likely would be per ormed to diagnose Wilm’s tumor? (A) (B) (C) (D) 234.

BE Upper GI IVU Bone survey

o visualize or “open” the right sacroiliac joint, the patient is positioned (A) (B) (C) (D)

30 to 40 degrees LPO 30 to 40 degrees RPO 25 to 30 degrees LPO 25 to 30 degrees RPO

235. Deoxygenated blood rom the head and thorax is returned to the heart by the (A) (B) (C) (D)

pulmonary artery pulmonary veins superior vena cava thoracic aorta

236. Which o the ollowing women is likely to have the most homogenous glandular breast tissue? (A) (B) (C) (D)

A postpubertal adolescent A 20-year-old with one previous pregnancy A menopausal woman A postmenopausal 65-year-old

237. Standard radiographic protocols may be reduced to include two views, at right angles to each other, in which o the ollowing situations? (A) (B) (C) (D)

Barium examinations Spine radiography Skull radiography Emergency and trauma radiography

238. Which o the ollowing structures is (are) located in the right upper quadrant (RUQ)? 1. Spleen 2. Gallbladder 3. Hepatic exure (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

239. Following the ingestion o a atty meal, what hormone is secreted by the duodenal mucosa to stimulate contraction o the gallbladder? (A) (B) (C) (D)

Insulin Cholecystokinin Adrenocorticotropic hormone Gastrin

240. Which o the ollowing projections is most likely to demonstrate the carpal pisi orm ree o superimposition? (A) (B) (C) (D)

Radial exion/deviation Ulnar exion/deviation AP (medial) oblique AP (lateral) oblique

241. Myelography is a diagnostic examination used to demonstrate 1. internal disk lesions 2. posttraumatic swelling o the spinal cord 3. posterior disk herniation (A) (B) (C) (D)

1 only 2 only 2 and 3 only 1, 2, and 3

242. Which o the ollowing blood chemistry levels must the radiographer check prior to excretory urography? 1. Creatinine 2. Blood urea nitrogen (BUN) 3. Red blood cells (RBCs) (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Questions: 232–248

243. Which o the ollowing are components o a trimalleolar racture?

248. Which o the ollowing is (are) well demonstrated in the lumbar spine shown in Figure 2-35?

1. Fractured lateral malleolus 2. Fractured medial malleolus 3. Fractured anterior tibia

1. Zygapophyseal articulations 2. Intervertebral oramina 3. In erior articular processes

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

244. T e unctions o which body system include mineral homeostasis, protection, and triglyceride storage? (A) (B) (C) (D)

Endocrine Integumentary Skeletal Muscular

245. T e our major arteries supplying the brain include the 1. brachiocephalic artery 2. common carotid arteries 3. vertebral arteries (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

246. Ingestion o barium sul ate is contraindicated in which o the ollowing situations? 1. Suspected per oration o a hollow viscus 2. Suspected large bowel obstruction 3. Preoperative patients (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 1, 2, and 3

247. T e term that re ers to parts away rom the source or beginning is (A) (B) (C) (D)

cephalad proximal distal lateral

71

Figure 2-35. Courtesy of Stamford Hospital, Department of Radiology.

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2: Imaging Procedures

249. Which o the ollowing statements is (are) correct, with respect to a le lateral projection o the chest? 1. T e MSP must be per ectly vertical and parallel to the IR. 2. T e right posterior ribs will be projected slightly posterior to the le posterior ribs. 3. Arms must be raised high to prevent upperarm so -tissue superimposition on lung eld. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

250. Which o the ollowing is represented by the number 3 in Figure 2-36? (A) (B) (C) (D)

In erior vena cava Aorta Gallbladder Psoas muscle

252. All the ollowing are palpable bony landmarks used in radiography o the pelvis except (A) (B) (C) (D)

the emoral neck the pubic symphysis the greater trochanter the iliac crest

253. Lateral deviation o the nasal septum may be best demonstrated in the (A) (B) (C) (D)

lateral projection PA axial (Caldwell method) projection parietoacanthal (Waters’ method) projection AP axial ( owne method) projection

254. T e AP rendelenburg position is o en used during an upper GI examination to demonstrate (A) the duodenal loop (B) lling o the duodenal bulb (C) hiatal hernia (D) hypertrophic pyloric stenosis 255. What is the structure labeled number 5 in Figure 2-37? (A) Base o the second metacarpal (B) Pisi orm (C) rapezium (D) rapezoid

Figure 2-36. Courtesy of Stamford Hospital, Department of Radiology.

251. Which o the ollowing bones participate(s) in the ormation o the knee joint?

1

4

2

5

3

6

1. Femur 2. ibia 3. Patella (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

Figure 2-37. Courtesy of Stamford Hospital, Department of Radiology.

Questions: 249–263

256. What is the structure labeled number 3 in Figure 2-37? (A) rapezium (B) Scaphoid (C) Ulnar styloid (D) Radial styloid

73

261. What is the degree o di erence between the baselines numbered 2 and 3 in Figure 2-38 and used or various projections o the skull? (A) (B) (C) (D)

7 degrees 8 degrees 15 degrees 23 degrees

257. In the anterior oblique position o the cervical spine, the CR should be directed (A) (B) (C) (D)

parallel to C4 perpendicular to C4 15 degrees cephalad to C4 15 degrees caudad to C4

1 2 3

258. Which o the ollowing is a unctional study used to demonstrate the degree o AP motion present in the cervical spine? (A) (B) (C) (D)

259. I a patient’s zygomatic arch has been traumatically depressed or the patient has at cheekbones, the arch may be demonstrated by modi ying the SMV projection and rotating the patient’s head (A) 15 degrees toward the side being examined (B) 15 degrees away rom the side being examined (C) 30 degrees toward the side being examined (D) 30 degrees away rom the side being examined 260. Which o the ollowing actors can contribute to hypertension? 1. Obesity 2. Smoking 3. Stress (A) (B) (C) (D)

4

Open-mouth projection Moving-mandible AP Flexion and extension laterals Right and le bending AP

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Figure 2-38.

262. Re erring to Figure 2-38, which o the ollowing positions requires that baseline number 3 be parallel to the IR? (A) (B) (C) (D)

Parietoacanthial PA axial (Caldwell) AP axial ( owne) SMV

263. Orthoroentgenography, or radiographic measurement o long bones o an upper or lower extremity, requires which o the ollowing accessories? 1. Bell-T ompson scale 2. Bucky tray 3. Cannula (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

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2: Imaging Procedures

264. Which o the ollowing is (are) demonstrated in a lateral projection o the cervical spine? 1. Intervertebral oramina 2. Zygapophyseal joints 3. Intervertebral joints

1. orbital oor 2. in erior rectus muscle 3. zygoma

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

265. In a lateral projection o the nasal bones, the CR is directed (A) (B) (C) (D) 266.

268. Structures involved in blowout ractures include the

½ inch posterior to the anterior nasal spine ½ inch posterior to the glabella ½ inch distal to the nasion ½ inch anterior to the EAM

o make a patient as com ortable as possible during a single-contrast barium enema (BE), the radiographer should 1. instruct the patient to relax the abdominal muscles to prevent intra-abdominal pressure. 2. instruct the patient to concentrate on breathing deeply to reduce colonic spasm. 3. prepare a warm barium suspension (98–105°F) to aid in retention. (A) (B) (C) (D)

2 only 1 and 2 only 2 and 3 only 1, 2, and 3

267. Which o the ollowing statements regarding knee x-ray arthrography is (are) true? 1. Ligament tears can be demonstrated. 2. Sterile technique is observed. 3. MRI can ollow x-ray. (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

269. Inspiration and expiration projections o the chest are per ormed to demonstrate 1. partial or complete collapse o pulmonary lobe(s) 2. air in the pleural cavity 3. oreign body (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

270. Shoulder arthrography is per ormed to 1. evaluate humeral luxation 2. demonstrate complete or partial rotator cu tear 3. evaluate the glenoid labrum (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

271. Which o the ollowing positions will separate the radial head, neck, and tuberosity rom superimposition on the ulna? (A) (B) (C) (D)

AP Lateral Medial oblique Lateral oblique

272. T e most signi cant risk actor or breast cancer is (A) (B) (C) (D)

age gender amily history personal history

Questions: 264–282

273. Which o the ollowing structures is located at the level o the interspace between the second and third thoracic vertebrae? (A) (B) (C) (D)

278. Below-diaphragm ribs are better demonstrated when 1. the patient is in the AP erect position 2. respiration is suspended at the end o ull exhalation 3. the patient is in the recumbent position

Manubrium Jugular notch Sternal angle Xiphoid process

(A) (B) (C) (D)

274. For the AP projection o the scapula, the 1. patient’s arm is abducted at right angles to the body. 2. patient’s elbow is exed with the hand supinated. 3. exposure is made during quiet breathing. (A) (B) (C) (D)

1 and 2 only 1 and 3 only 3 only 1, 2, and 3

275. T e innominate bone is located in the (A) (B) (C) (D)

middle cranial ossa posterior cranial ossa oot pelvis

276. T e sternoclavicular joints are best demonstrated with the patient PA and (A) in a slight oblique position, a ected side adjacent to the IR (B) in a slight oblique position, a ected side away rom the IR (C) erect and weight-bearing (D) erect with and without weights 277. Which o the ollowing sinus groups is demonstrated with the patient positioned as or a parietoacanthal projection (Waters’ method) with the CR directed through the patient’s open mouth? (A) (B) (C) (D)

Frontal Ethmoidal Maxillary Sphenoidal

75

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

279. Which o the ollowing positions is essential in radiography o the paranasal sinuses? (A) Erect (B) Recumbent (C) Oblique (D) rendelenburg 280. What projection o the os calsis is obtained with the leg extended, the plantar sur ace o the oot vertical and perpendicular to the IR, and the CR directed 40 degrees cephalad? (A) (B) (C) (D) 281.

Axial plantodorsal projection Axial dorsoplantar projection Lateral projection Weight-bearing lateral projection

o demonstrate the rst two cervical vertebrae in the AP projection, the patient is positioned so that (A) the glabellomeatal line is vertical (B) the acanthiomeatal line is vertical (C) a line between the mentum and the mastoid tip is vertical (D) a line between the maxillary occlusal plane and the mastoid tip is vertical

282. With a patient in the PA position and the OML perpendicular to the table, a 15- to 20-degree caudal angulation would place the petrous ridges in the lower third o the orbit. o achieve the same result in a baby or a small child, it is necessary or the radiographer to modi y the angulation to (A) (B) (C) (D)

10 to 15 degrees caudal 25 to 30 degrees caudal 15 to 20 degrees cephalic 3 to 5 degrees caudal

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2: Imaging Procedures

283. T e structure labeled number 6 in Figure 2-39 is the (A) (B) (C) (D)

286. Which o the ollowing positions demonstrates the sphenoid sinuses? 1. Modi ed Waters’ (mouth open) 2. Lateral 3. PA axial

le subclavian artery brachiocephalic artery right common carotid artery le vertebral artery

(A) (B) (C) (D)

4 5 6 7

3 2

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

287. T e number 2 in Figure 2-40 represents which o the ollowing structures? (A) (B) (C) (D)

1

Body Pedicle In erior articular process Superior articular process 4

6

3

5 1 2

Figure 2-39. Reproduced, with permission, from Doherty GM, ed. Current Surgical Diagnosis &Treatment, 12th ed. New York: McGraw-Hill, 2006:824.

Figure 2-40.

288. 284. T e structure labeled number 3 in Figure 2-39 is the (A) (B) (C) (D)

le subclavian artery brachiocephalic artery right common carotid artery le vertebral artery

285. In the lateral projection o the oot, the

o demonstrate the mandibular body in the PA position, the (A) (B) (C) (D)

CR is directed perpendicular to the IR CR is directed cephalad to the IR skull is obliqued away rom the a ected side skull is obliqued toward the a ected side

289. Which o the ollowing equipment is necessary or ERCP?

1. plantar sur ace should be perpendicular to the IR 2. metatarsals are superimposed 3. talo bular joint should be visualized

1. A uoroscopic unit with imaging device and tilt-table capabilities 2. A beroptic endoscope 3. Polyethylene catheters

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

Questions: 283–297

290.

ypes o mechanical obstruction ound in pediatric patients include 1. volvulus 2. intussusception 3. paralytic ileus (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

291. T e act o expiration will cause the 1. diaphragm to move in eriorly 2. sternum and ribs to move in eriorly 3. diaphragm to move superiorly (A) (B) (C) (D)

294. Which o the ollowing positions will best demonstrate the right zygapophyseal articulations o the lumbar vertebrae? (A) (B) (C) (D)

PA Le lateral RPO LPO

295. What projection was used to obtain the image seen in Figure 2-41? (A) (B) (C) (D)

AP, internal rotation AP, external rotation AP, neutral position AP axial

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

1 2

292. A patient unable to extend his or her arm is seated at the end o the x-ray table, elbow exed 90 degrees. T e CR is directed 45 degrees medially. Which o the ollowing structures will be demonstrated best? 1. Radial head 2. Capitulum 3. Coronoid process (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

293. Which o the ollowing articulate(s) with the bases o the metatarsals? 1. T e heads o the rst row o phalanges 2. T e cuboid 3. T e cunei orms (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

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3 4 5

Figure 2-41. Courtesy of Conrad P. Ehrlich, M.D.

296. T e structure labeled number 4 in Figure 2-41 is the (A) (B) (C) (D)

acromion process coracoid process coronoid process glenoid process

297. T e structure labeled number 5 in Figure 2-41 is the (A) (B) (C) (D)

sternoclavicular joint acromioclavicular joint glenohumeral joint acromiohumeral joint

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2: Imaging Procedures

298. Which o the ollowing is demonstrated in a 25-degree RPO position with the CR entering 1 inch medial to the elevated ASIS? (A) (B) (C) (D)

Le sacroiliac joint Right sacroiliac joint Le ilium Right ilium

299. Which o the ollowing positions is most likely to place the right kidney parallel to the IR? (A) (B) (C) (D)

AP PA RPO LPO

300. A lateral projection o the larynx is occasionally required to rule out oreign body, polyps, or tumor. T e CR should be directed (A) (B) (C) (D)

just below the EAM to the level o the mandibular angles to the level o the laryngeal prominence to the level o C7

Answers and Explanations

1. (A) T e term valgus re ers to a part turned/ de ormed outward—as in hallux valgus and talipes valgus. Hallux valgus is angulation o the great toe away rom the midline; talipes valgus is a oot de ormity with the heel turned outward—a component o club oot. T e term varus re ers to bent or turned inward. In genu varus, the tibia or emur turns inward causing bowlegged de ormity; in talipes varus, the oot turns inward (club oot de ormity). 2. (D) T ere are three important at pads associated with the elbow, best demonstrated in the true lateral projection. T ey are not demonstrated in the AP projection because o their superimposition on bony structures. T e anterior at pad is located just anterior to the distal humerus. T e posterior at pad is located within the olecranon ossa at the distal posterior humerus. T e supinator at pad/stripe is located at the proximal radius just anterior to the head, neck, and tuberosity. T e posterior at pad is not visible radiographically in the normal elbow. T e posterior at pad is visible in cases o trauma or other pathology and when the elbow is insuf ciently exed. 3. (C) Long bones are composed o a body/sha , or diaphysis, and two extremities. T e diaphysis is the primary ossi cation center. In the growing bone, the cartilaginous epiphyseal plate (located at the extremities o long bones) is gradually replaced by bone. T e epiphyses are re erred to as the secondary ossi cation centers. T e wider portion o bone adjacent to the epiphyseal plate is the metaphysis—that portion o long bone where

lengthening/bone growth takes place. Apophysis re ers to a bony projection without an independent ossi cation center. 4. (D) T e lateral oblique elbow projection demonstrates the proximal radius and ulna ree o superimposition. T e coronoid process is located on the proximal anterior ulna. T e medial oblique projection o the elbow demonstrates the coronoid process in pro le, as well as the ulnar olecranon process within the humeral olecranon ossa. T e coracoid process is located on the scapula. 5. (B) he male and emale bony pelves have several di ering characteristics; male/ emale pelvic anatomy di ers more then any other body anatomy. An overview o comparisons is listed below. Male pelvis • T e general structure is heavy and thick. • T e greater, or alse, pelvis is deep. • T e pelvic brim, or inlet, is small and heartshaped. • T e acetabulum is large and aces laterally. • T e pubic angle is less than 90 degrees. • T e ilium is more vertical. Female pelvis • T e general structure is light and thin. • T e greater, or alse, pelvis is shallow. • T e pelvic brim, or inlet, is large and oval. • T e acetabulum is small and aces anteriorly. • T e pubic angle is more than 90 degrees. • T e ilium is more horizontal.

79

80

2: Imaging Procedures

6. (C) In the PA position, portions o the bariumlled hypersthenic stomach superimpose on themselves. T us, patients with a hypersthenic body habitus usually present a high transverse stomach with poorly de ned curvatures. I the PA stomach is projected with a 35- to 45-degree cephalad CR, the stomach “opens up.” T at is, the curvatures, the antral portion, and the duodenal bulb all appear as a sthenic habitus stomach would appear. A 35- to 40-degree RAO position is used to demonstrate many o these structures in the average, or sthenic, body habitus. A lateral position is used to demonstrate the anterior and posterior gastric sur aces and retrogastric space. 7. (B) Note the relationship between the thigh, lower leg, patella, and CR. T e CR is directed parallel to the plane o the patella, thereby providing a tangential projection o the patella (i.e., patella in pro le) and an unobstructed view o the patello emoral articulation (Fig. 2-42). Figure 2-2 illustrates how the image is obtained with the patient in the prone position. Many patients may not be able to assume the prone position. T e same relationship between the CR, part, and IR can be obtained with the patient in the lateral recumbent position or the seated position (see Fig. 2-42A and B). T e erect AP would superimpose the patella on other bony structures. 8. (A) T e trachea bi urcates into le and right main stem bronchi, each entering its respective lung hilum. T e le bronchus divides into two portions,

one or each lobe o the le lung. T e le lung has 1 ssure: the oblique. T e right bronchus divides into three portions, one or each lobe o the right lung (Fig. 2-43). T e right lung has 2 ssures: the horizontal and the oblique. T e lungs are conical in shape, consisting o upper pointed portions, termed the apices (plural o apex), and broad lower portions (or bases). T e lungs are enclosed in a double-walled serous membrane called the pleura. 9. (C) In the exact PA projection o the skull, the perpendicular CR exits the nasion and the petrous pyramids should be demonstrated lling the orbits (Fig. 2-44). As the CR is angled caudally, the petrous ridges/pyramids are projected lower in the orbits. At about 25 to 30 degrees caudad they are projected below the orbits. T e OML must be perpendicular to the IR or the petrous pyramids to be projected into the expected location, that is, within the orbital cavities. T e MSP must be perpendicular to the IR, or the skull will be rotated and le /right symmetry will be lost. 10. (D) T e gure illustrates a PA projection o the chest. T is projection demonstrates the air- lled trachea, the carina at the bi urcation o the trachea, the lungs rom apices to costophrenic angles, both hemidiaphragms, the heart and aortic arch. T e shoulders have been rolled orward to e ectively remove the scapulae rom the lung elds. Adequate inspiration is demonstrated by visualization o 10 posterior ribs above the diaphragm (see numbered ribs in Fig. 2-45).

CR

CR A

B

Figure 2-42.

Answers: 6–13

81

Figure 2-43. Reproduced, with permission, from Montgomery RL. Appleton &Lange’s Review of Anatomy for the USMLE Step I. East Norwalk, CT: Appleton &Lange, 1995:27.

11. (D) Pacemakers are electromechanical devices that help to regulate the heart rate. T ey consist o a pulse generator connected to a lead that has an electrode at its tip. T e lead is introduced under uoroscopic guidance into the subclavian vein, then o en moved to the right atrium, and then positioned at the apex o the right ventricle.

actors. Pneumonia is in ammation o the lungs, usually caused by bacteria, virus, or chemical irritant. Pneumothorax is a collection o air or gas in the pleural cavity (outside the lungs), with an accompanying collapse o the lung. Pleural e usion is excessive uid between the parietal and visceral layers o pleura.

12. (C) Chest radiographs demonstrating emphysema will show the characteristic irreversible trapping o air that increases gradually and overexpands the lungs. T is produces the characteristic “ attening” o the hemidiaphragms and widening o the intercostal spaces. T e increased air content o the lungs requires a compensating decrease in technical

13. (B) T e cecum is a blind pouch located at the most proximal ( rst) portion o the large intestine. Extending rom the lower end o the cecum is the worm-like vermi orm appendix. T e cecum and the vermi orm appendix are both located in the right lower quadrant (RLQ). T e sigmoid is located in the le lower quadrant (LLQ).

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2: Imaging Procedures

14. (A) T e image shown is one o a series o IVU images taken 15 minutes a er injection o the contrast medium. T e urinary collecting system is well demonstrated. An RPO position is illustrated, with the right marker indicating the right side; also, the right ilium is more “open” (i.e., parallel to the IR) than the le . T e RPO position places the le kidney and right ureter parallel to the IR. T e urinary bladder contains considerable contrast, indicating that it is most likely a prevoid image.

Figure 2-44. Courtesy of Stamford Hospital, Department of Radiology.

15. (D) In the recumbent position, the upper portion o the stomach occupies a more posterior position in the body than the distal aspect o the stomach. T ere ore, in the AP recumbent position (or LPO position), barium moves easily into the undus o the stomach ( rom the more distal portions o the stomach), displacing/drawing the stomach somewhat superiorly. T e undus is lled with barium, whereas the air that had been in the undus is now displaced into the gastric body, pylorus, and duodenum, illustrating them in double contrast. Double-contrast delineation o these structures allows us to see through the stomach to the retrogastric areas and structures. T e RAO position demonstrates a barium- lled pylorus and duodenum. Anterior and posterior aspects o the stomach are visualized in the lateral position; medial and lateral aspects o the stomach are visualized in the AP projection.

1 2

16. (B) he ankle mortise, or ankle joint, is ormed by the articulation o the tibia, ibula, and talus (Fig. 2-46). wo articulations orm the ankle mortise: the talotibial and talo ibular articulations. he calcaneus is not associated with ormation o the ankle mortise.

3 4

5

6

7

17. (C) T e oot has anterior, posterior, medial, and lateral sur aces. T e upper sur ace is the anterior, or dorsum/dorsal sur ace. T e lower sur ace is the plantar sur ace. Hence, the AP projection o the oot is also called the dorsoplantar projection o the oot (describing the path o the CR traversing rom dorsum to plantar sur ace).

8

9

10

Figure 2-45.

18. (D) T e walls o the digestive tract/alimentary canal rom outer to inner are: serosa, muscularis, submucosa, mucosa. T e outermost serosa is thin and membranous. T e muscular layer assists with peristaltic activity and the ormation o sphincter muscles. T e submucosa is a airly thick layer o

Answers: 14–22

83

Figure 2-47.

Figure 2-46.

loose connective tissue. T e mucosa is the innermost layer which orms orms called ruga.

and posterior clinoid processes o the sphenoid bone should be visualized within the oramen magnum. T is projection may also be obtained by angling the CR 30 degrees caudad to the OML (Fig. 2-47). T e rontal bone is best shown with the patient PA and with a perpendicular CR. T e parietoacanthal projection is the single best position or acial bones. Basal oramina are well demonstrated in the submentovertical projection.

19. (B) Plantar f exion describes upward movement o the oot and toes, decreasing the angle between the dorsum (upper sur ace) o the oot and lower leg. T is movement can be used in projections o the calcaneus. T e term valgus re ers to a part turned/ de ormed outward—as in hallux valgus and talipes valgus. Hallux valgus is angulation o the great toe away rom the midline; talipes valgus is a oot de ormity with the heel turned outward—a component o club oot. T e term valgus can also be used to describe the eversion position used in stress projections o the ankle. T e term oblique is a term used in positioning that re ers to longitudinal sections or body planes.

21. (B) T e posterior oblique projection o the acetabulum (Judet method) requires a 45-degree obliquity o the entire MSP. In the RPO position, the down side (the right side in this case) will demonstrate the anterior rim o the right acetabulum, the right posterior ilioischial column, and the right iliac wing. When centered to the up side (le in this case), the structures demonstrated are the posterior rim o the le acetabulum, le anterior iliopubic column, and the le obturator oramen.

20. (A) T e AP axial projects the anterior structures ( rontal and acial bones) downward, thus permitting visualization o the occipital bone without superimposition ( owne method). T e dorsum sella

22. (D) T e gure illustrates a PA projection o the chest and the side marker correctly placed. T e heart is seen on the right side—this is termed dextrocardia. Atelectasis (partial or complete collapse

84

2: Imaging Procedures

o lung) would be demonstrated as increased tissue density in the a ected area. A classic pneumothorax (air within the thoracic cavity) would demonstrate an absence o lung markings in the a ected area and attening o the hemidiaphragm on the a ected side. A small pneumothorax can be easily missed on a chest image having excessive density. 23. (C) Because the sternum and vertebrae would be superimposed in a direct PA or AP projection, a slight oblique (just enough to separate the sternum rom superimposition on the vertebrae) is used instead o a direct rontal projection. In the RAO position, the heart superimposes a homogenous density over the sternum, thereby providing more clear radiographic visualization o its bony structure. I the LAO position were used to project the sternum to the right o the thoracic vertebrae, the posterior ribs and pulmonary markings would cast con using shadows over the sternum because o their di ering densities. 24. (C) T e orward slipping o one vertebra on the one below it is called spondylolisthesis. Spondylolysis is the breakdown o the pars interarticularis; it may be unilateral or bilateral and results in orward slipping o the involved vertebra—the condition o spondylolisthesis. In ammation o one or more vertebrae is called spondylitis. Spondylosis re ers to degenerative changes occurring in the vertebra. 25. (B) Statement number 1 describes the PA axial projection (Camp-Coventry method) or demonstration o the intercondyloid ossa. Statement number 2 describes the AP axial projection (Béclère method) or demonstration o the intercondyloid ossa. T e positions are actually the reverse o each other. Statement number 3 describes the method o obtaining a PA projection o the patella. 26. (C) One o the most important principles in chest radiography is that it be per ormed, whenever possible, in the erect position. It is in this position that the diaphragm can descend to its lowest position during inspiration, and any air– uid levels can be detected. However, patients having traumatic injuries requently must be examined in the supine position. An AP supine chest is per ormed rst. I the examination is also being per ormed to rule out air– uid levels, this can be determined by

per orming the lateral projection in the dorsal decubitus position. T e patient is lying supine, and a horizontal (cross-table) x-ray beam is used. 27. (C) Met ormin hydrochloride (Glucophage) is used as an adjunct to appropriate diet to lower blood glucose levels in patients who have type 2 diabetes and whose hyperglycemia is not being managed satisactorily with diet alone. Patients on Glucophage who are having intravascular iodinated contrast studies can develop an acute alteration o renal unction or acute acidosis. It is recommended that patients on Met ormin hydrochloride (Glucophage) have it withheld 48 hours a er the examination. 28. (C) T e radiograph shown is a PA projection (Caldwell method) o the rontal and anterior ethmoidal sinuses. T e rontal sinuses are seen centrally in the vertical plate o the rontal bone behind the glabella and extending laterally over the superciliary arches. T e ethmoidal sinuses are seen adjacent and in erior to the medial aspect o the orbits. T e patient is positioned PA erect with the chin extended so that the OML is 15 degrees rom the horizontal. With the OML perpendicular to the IR, the petrous pyramids would ll the orbits (true PA). In the PA position with chin extended (choice A) and OML 37 degrees to the IR (parietoacanthial projection, Waters’ method), the petrous pyramids are projected below the maxillary sinuses. 29. (D) T e radiograph shown is a PA projection (Caldwell method) o the rontal and anterior ethmoid sinuses. T e rontal sinuses are seen centrally in the vertical plate o the rontal bone behind the glabella and extending laterally over the superciliary arches. T e ethmoid sinuses are seen adjacent and in erior to the medial aspect o the orbits. T e nasal cavity is seen, with the perpendicular plate and vomer, in the midline. T e patient is positioned PA erect with the chin extended so that the OML is 15 degrees rom the horizontal. 30. (A) T e oblique projection o the hand should demonstrate minimal overlap o the third, ourth, and h metacarpals. Excessive overlap o these metacarpals is caused by obliquing the hand more than 45 degrees. T e use o a 45-degree oam wedge ensures that the ngers will be extended and parallel to the IR, thus permitting visualization o the

Answers: 23–36

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interphalangeal joints and avoiding oreshortening o the phalanges. Clenching o the st and ulnar exion are maneuvers used to better demonstrate the carpal scaphoid. 31. (A) Sternoclavicular articulations may be examined with the patient PA, either bilaterally with the patient’s head resting on the chin or unilaterally with the patient’s head turned toward the side being examined. T e sternoclavicular articulations also may be examined in the oblique position, with either the patient rotated slightly or the CR angled slightly medialward. Weight-bearing positions are used requently or evaluation o acromioclavicular joints. 32. (B) Various terms are used to describe the position o ractured ends o long bones. T e term apposition is used to describe the alignment, or misalignment, between the ends o ractured long bones. T e term angulation describes the direction o misalignment. T e term luxation re ers to a dislocation. A sprain re ers to a wrenched articulation with ligament injury. 33. (D) A decubitus projection is obtained using a horizontal x-ray beam. T e type o decubitus projection is dependent on the patient’s recumbent position. When the patient is lying AP recumbent (i.e., supine), the patient is said to be in the dorsal decubitus position. When the patient is lying prone, he or she is in the ventral decubitus position. I the patient is lying in the le or right lateral recumbent position with the x-ray beam directed horizontally, the patient is said to be in the le or right lateral decubitus position, respectively. 34. (A) Air or uid levels will be clearly delineated only i the CR is directed parallel to them. T ereore, to demonstrate air or uid levels, the erect or decubitus position should be used. Small amounts o f uid within the peritoneal or pleural space are best demonstrated in the lateral decubitus position, a ected side down. Small amounts o air within the peritoneal or pleural space are best demonstrated in the lateral decubitus position, a ected side up. 35. (C) T e relationship o these three structures is easily appreciated in a lateral projection o the chest. T e heart is seen in the anterior hal o the

Figure 2-48. From the American College of Radiology Learning File. Courtesy of the ACR.

thoracic cavity, with its apex extending in erior and anterior. T e air- lled trachea can be seen in about the center o the chest, and the air- lled esophagus is seen just posterior to the trachea (Fig. 2-48). T e superimposed vertebral and axillary borders o the scapulae would be seen most posteriorly. 36. (D) T e knee structures are ormed by the proximal tibia, the patella, and the distal emur, which articulate to orm the emorotibial and emoropatellar joints. T e knee joint is the emorotibial joint. Body habitus can considerably change the knee joint and tabletop/IR relationship. T e CR should be directed to 1⁄2 in below patellar apex (knee joint). T e direction o CR depends on distance between the ASIS and tabletop/IR. When this distance is up to 19 cm (thin pelvis), the CR should be directed 3 to 5 degrees caudad; when the distance is between 19 to 24 cm, the CR is directed vertically/ perpendicular (0 degrees); when the distance is greater than 24 cm (thick pelvis), the CR is directed 3 to 5 degrees cephalad.

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2: Imaging Procedures

37. (B) he image illustrates a medial oblique (internal rotation) projection o the elbow with epicondyles 45 degrees to the IR. An oblique view o the proximal radius and ulna and the distal humerus is obtained. his projection is particularly use ul to demonstrate the coronoid process in pro ile, the trochlea, and the medial epicondyle. he external oblique (lateral rotation) projection demonstrates the radial head ree o superimposition as well as the radial neck and the humeral capitulum. he acute lexion projection (Jones Method) o the elbow is a twoprojection method demonstrating the elbow anatomy when the part cannot be extended or an AP projection. 38. (D) T e image illustrates a medial oblique (internal rotation) projection o the elbow with epicondyles 45 degrees to the IR. An oblique view o the proximal radius and ulna and the distal humerus is obtained. T is projection is particularly use ul to demonstrate the coronoid process in pro le (number 4), the trochlea (number 3), and the medial epicondyle (number 1). T e olecranon process (number 2) ts into the olecranon ossa during extension o the elbow. A small portion o the radial head (number 5) not superimposed on the ulna can be seen. T e external oblique (lateral rotation) projection demonstrates the entire radial head ree o superimposition as well as the radial neck and the humeral capitulum. 39. (C) A lateral projection o the lumbar spine is illustrated. T e intervertebral articulations (disk spaces) are well demonstrated. Because the intervertebral oramina, which are ormed by the pedicles, are 90 degrees to the MSP, they are also well demonstrated in the lateral projection. T e articular acets, orming the zygapophyseal joints, lie 30 to 50 degrees to the MSP and are visualized in the oblique position. 40. (C) An intrathecal injection is one made within the spinal meninges. A myelogram requires an intrathecal injection to introduce contrast medium into the subarachnoid space. An IVU requires an intravenous injection; a retrograde pyelogram requires that contrast medium be introduced into the ureters by way o cystoscopy. A cystogram requires that contrast medium be introduced via catheter into the urinary bladder.

41. (A) A diagnostic image o C1–2 depends on adjusting the exion o the neck so that the maxillary occlusal plane and the base o the skull are superimposed. Accurate adjustment o these structures usually will allow good visualization o the odontoid process and the atlantoaxial articulation. Should patient anatomy occasionally prevent the usual visualization, the odontoid process can be visualized through the oramen magnum, either AP or PA. In the AP position (Fuchs method) or the PA position (Judd method), the patient’s chin is extended to be in line vertically with the mastoid tip (similar to a Waters’ or reverse Waters’ position). T e CR is directed to the midline and perpendicularly at the level o the mastoid tip. T e resulting image demonstrates the odontoid process through the oramen magnum. T ese positions should not be attempted i the patient has a suspected, new, or healing racture or destructive disease. 42. (B) T e skull is divided into two parts—the cranial bones and the acial bones. T ere are eight cranial bones. Four o them comprise the calvarium— the rontal, the two parietals, and the occipital. T e bones that comprise the f oor o the cranium are the two temporals, the ethmoid, and the sphenoid. 43. (C) T e lateral hand in extension, with appropriate technique adjustment, is recommended to evaluate oreign-body location in so tissue. A small lead marker requently is taped to the spot thought to be the point o entry. T e physician then uses this external marker and the radiograph to determine the exact oreign-body location. Extension o the hand in the presence o a racture would cause additional and unnecessary pain and possibly additional injury. 44–45. (44, A; 45, B) T e radiograph shown is an oblique position o a double-contrast study o the large bowel, illustrating an “open” view o the splenic/le colic exure (number 1) and descending colon, with the hepatic/right colic exure (number 2) somewhat superimposed on the transverse and ascending (number 3) colon. T ere ore, the radiograph must have been made in either an RPO (i the patient was supine) or an LAO (i the patient was prone) position. T e LPO and RAO positions are used to demonstrate the hepatic exure and ascending colon ree o sel -superimposition. T e distal ilium is well visualized (number 6), as well as

Answers: 37–54

the commencement o the large bowel—the cecum (number 4)—and its vermi orm appendix (number 5). T e AP or PA axial position generally is used to visualize the rectosigmoid colon. 46. (C) T e ductus arteriosus is a short etal blood vessel connecting the aorta and pulmonary artery that usually closes within 10 to 15 hours a er birth. A patent ductus arteriosus is one that persists and requires surgical closure. Atrial septal de ect is a small hole (the remnant o the etal oramen ovale) in the interatrial septum. It usually closes spontaneously in the rst months o li e; i it persists or is unusually large, surgical repair is necessary. Ventricular septal de ect is a congenital heart condition characterized by a hole in the interventricular septum that allows oxygenated and unoxygenated blood to mix. Some interventricular septal de ects are small and close spontaneously; others require surgery. Coarctation o the aorta is a narrowing or constriction o the aorta. 47. (D) T e scapular Y re ers to the characteristic Y ormed by the humerus, acromion, and coracoid processes. T e patient is placed in a PA oblique position—an RAO or LAO position depending on which is the a ected side. T e midcoronal plane is adjusted approximately 60 degrees to the IR, and the a ected arm remains relaxed at the patient’s side. T e scapular Y position is employed to demonstrate anterior (subcoracoid) or posterior (subacromial) humeral dislocation. T e humerus normally is superimposed on the scapula in this position; any deviation rom this may indicate dislocation. 48. (B) T e hilus (hilum) is the slit-like opening on the medial aspect o the lung through which arteries, veins and lymphatics enter and exit. T e carina is an internal ridge located at the bi urcation o the trachea into right and le primary, or main stem, bronchi. T e epiglottis is a ap o elastic cartilage that unctions to prevent uids and solids rom entering the respiratory tract during swallowing. T e root o the lung attaches the lung, via dense connective tissue, to the mediastinum. T e root o the le lung is at the level o 6, and the root o the right is at 5. 49. (C) T e axillary portion o the ribs is best demonstrated in a 45-degree oblique position. T e axillary ribs are demonstrated in the AP oblique projection with the a ected side adjacent to the IR and in the PA oblique projection with the a ected

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side away rom the IR. T ere ore, the right axillary ribs would be demonstrated in the RPO (AP oblique with a ected side adjacent to the IR) and LAO (PA oblique with a ected side away rom the IR) positions. 50. (A) T e lateral oblique demonstrates the interspaces between the rst and second metatarsals and between the rst and second cunei orms. o best demonstrate most o the tarsals and intertarsal spaces (including the cuboid, sinus tarsi, and tuberosity o the h metatarsal), a medial oblique projection is required (plantar sur ace and IR orm a 30-degree angle). A weight-bearing lateral projection o the eet is used to demonstrate the longitudinal arches. 51. (C) Sur ace landmarks, prominences, and depressions are very use ul to the radiographer in locating anatomic structures that are not visible externally. T e h thoracic vertebra is at approximately the same level as the sternal angle. T e 2–3 interspace is about at the same level as the manubrial (suprasternal) notch. T e costal margin is about the same level as L3. 52. (C) Blood pressure in the pulmonary circulation is relatively low, and there ore, pulmonary vessels can easily become blocked by blood clots, air bubbles, or atty masses, resulting in a pulmonary embolism. I the blockage stays in place, it results in an extra strain on the right ventricle, which is now unable to pump blood. T is can result in congestive heart ailure. Pneumothorax is air in the pleural cavity. Atelectasis is a collapsed lung or part o a lung. Hypoxia is a condition o low tissue oxygen. 53. (A) Esophageal varices are tortuous dilatations o the esophageal veins. T ey are much less pronounced in the erect position and always must be examined with the patient recumbent. T e recumbent position a ords more complete lling o the veins because blood ows against gravity. 54. (A) A PA oblique projection o the hand is shown. T e correct degree o obliquity (45 degrees) is evidenced by no overlap o midsha third, ourth, and h metacarpals and minimal overlap o their heads. T e phalanges are oreshortened and the interphalangeal joint spaces are not visualized because the ngers are not adjusted to be parallel to the IR.

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2: Imaging Procedures

55. (B) Within the body/sha o a long bone is the medullary cavity, containing bone marrow and lined by a membrane called endosteum. In adults, yellow marrow is the most abundant and occupies the body/sha , and red marrow is ound within the proximal and distal extremities o long bones. Bone marrow, particularly red, is important in the production o blood cells—a process called hematopoiesis.

popliteal sur ace, whereas the distal anterior sur ace presents the patellar sur ace. Proximally, the emur presents a head, neck, and greater and lesser trochanters. T e intertrochanteric crest is a prominent ridge o bone between the trochanters posteriorly; anteriorly the intertrochanteric line is seen. T e emoral head presents a roughened prominence, the ovea capitis emoris—ligaments attached here secure the emoral head to the acetabulum.

56. (C) T e emur is the longest and strongest bone in the body. T e emoral sha is bowed slightly anteriorly and presents a long, narrow ridge posteriorly called the linea aspera. T e distal emur is associated with two large condyles; the deep depression separating them posteriorly is the intercondyloid ossa (Fig. 2-49). Just superior to the large condyles are the smaller medial and lateral epicondyles. T e posterior distal emoral sur ace presents the

57. (A) T e 15-degree medial oblique projection is used to demonstrate the ankle mortise (joint). Although the joint is well demonstrated in the 15-degree medial oblique projection, there is some superimposition o the distal tibia and bula, and greater obliquity is required to separate the bones. o best demonstrate the distal tibio bular articulation, a 45-degree medial oblique projection o the ankle is required.

Fove a ca pitis fe moris

He a d Gre a te r trocha nte r

Gre a te r trocha nte r

He a d Ne ck

Le s s e r trocha nte r

Ne ck Le s s e r trocha nte r

Line a a s pe ra S ha ft

La te ra l e picondyle

S ha ft

La te ra l s upra condyla r line Me dia l s upra condyla r line

Me dia l e picondyle

Inte rcondyla r fos s a La te ra l condyle

Me dia l condyle

Ante rio r

Me dial

Figure 2-49.

Me dia l condyle Po s te rio r

La te ra l condyle

Answers: 55–66

58. (C) Pneumothorax results rom an accumulation o air in the plural cavity, resulting in partial or complete collapse o the associated lung. T e a ected lung in this case can be seen displaced away rom the chest wall. Pleural e usion is also demonstrated here by an accumulation o uid in the pleural cavity. Air/ uid levels are well demonstrated in the erect position. In emphysema, however, air is trapped in the alveoli, it is a condition that is characterized by increased amount o air in the lungs, attening o the hemidiaphragms, and widening o the intercostal spaces. Notice that Figure 2-11 has an expiration marker—recall that a pneumothorax diagnosis usually requires inspiration and expiration images. 59. (A) T e in erior costal margin (in erior margin o the ribs) is located at the level o L2–L3. T e ASIS is in the same transverse plane as S2. T e ASIS and the pubic symphysis are the bony landmarks used to locate the hip joint, which is located midway between the two points. T e uppermost portion o the iliac crest is at the approximate level o L4–L5. T e most prominent part o the greater trochanter is at the same level as the pubic symphysis—both are valuable positioning landmarks. 60. (B) When placed in the recumbent lateral position, the average adult’s lumbar spine will not be parallel to the x-ray tabletop. Because the shoulders and hips generally are wider than the waist, the vertebral column slopes downward in the central areas—making the lower thoracic and upper lumbar spine closer to the tabletop than the upper thoracic and lower lumbar spine. One solution is to place a radiolucent sponge under the patient’s waist. T is will elevate the sagging spinal area and make the vertebral column parallel to the x-ray tabletop and IR. It will also open the intervertebral disks better, placing more o them parallel to the path o the x-ray photons and perpendicular to the IR. T is position also places the intervertebral oramina parallel with the path o the CR. T e radiolucent sponge is strictly a positioning aid and has no impact on the amount o SR reaching the IR. 61. (D) T e scapular Y projection is an oblique projection o the shoulder that is used to demonstrate anterior or posterior shoulder dislocation. T e in erosuperior axial projection may be used to evaluate the glenohumeral joint when the patient is

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able to abduct the arm. T e transthoracic lateral projection is used to evaluate the glenohumeral joint and upper humerus when the patient is unable to abduct the arm. 62. (A) T e knee ( emorotibial) joint is ormed by the emur and tibia. T e most superior aspect o the tibia is the tibial plateau— ormed by the tibial condyles just distal to it. T e proximal tibia also presents the tibial tuberosity on its anterior sur ace, just distal to the condyles. Proximal to the tibial plateau, and articulating with it, are the emoral condyles—the deep notch separating them is the intercondyloid ossa. T e term proximal re ers to a part located closer to the point o attachment; the term distal re ers to a part located arther away rom the point o attachment. 63. (C) T e greater and lesser tubercles are prominences on the proximal humerus separated by the intertubercular (bicipital) groove. T e lateral projection o the humerus places the shoulder in extreme internal rotation with the epicondyles perpendicular to the IR and superimposed. T e lateral projection o the humerus should demonstrate the lesser tubercle in pro le. T e AP projection o the humerus/shoulder places the epicondyles parallel to the IR and the shoulder in external rotation and demonstrates the greater tubercle in pro le. 64. (D) T e mediastinum is the space between the lungs that contains the heart, great vessels, trachea, esophagus, and thymus gland. It is bounded anteriorly by the sternum and posteriorly by the vertebral column, and extends rom the upper thorax to the diaphragm. 65. (D) When the clavicle is examined in the PA recumbent position, the CR must be directed 15 to 30 degrees caudad to project most o the clavicle’s length above the ribs. T e direction o the CR is reversed when examining the patient in the AP position. 66. (A) An avulsion racture is a small bony ragment pulled rom a bony process as a result o a orce ul pull o the attached ligament or tendon. A comminuted racture is one in which the bone is broken or splintered into pieces. A torus racture is a greenstick racture with one cortex buckled and the other intact. A compound racture is an open racture in which the ractured ends have per orated the skin.

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2: Imaging Procedures

Coronoid fos s a

Hume rus

Ole cra non fos s a

Me dia l e picondyle

Ole cra non proce s s

Trochle a

Ca pitulum

Ulna Ra dius

Ante rio r

Po s te rio r

Figure 2-50.

67. (D) T e distal humerus articulates with the proximal radius and ulna to orm the elbow joint. Speci ically, the semilunar/trochlear notch o the proximal ulna articulates with the trochlea o the distal medial humerus. T e capitulum is lateral to the trochlea and articulates with the radial head (Fig. 2-50). 68. (D) T ese are all terms used to describe particular body movements. Eversion re ers to movement o the oot caused by turning the ankle outward. Inversion is oot motion caused by turning the ankle inward. Abduction is movement o a part away rom the midline. Adduction is movement o a part toward the midline. 69. (B) T e central nervous system (brain and spinal cord) is located within three protective membranes, the meninges. T e inner membrane is the pia mater, the middle membrane is the arachnoid, and the outer membrane is the dura mater. T e subarachnoid space is located between the pia and arachnoid mater and contains cerebrospinal uid (CSF). During myelography, the needle is introduced into the subarachnoid space (L3–4 or L4–5), a small amount o CSF is removed, and the contrast medium is introduced (Fig. 2-51). T e subdural space is located between the arachnoid and dura mater. T e epidural space is located between the two layers o the dura mater. 70. (C) T e skull has two major parts: the cranium, which is composed o 8 bones and houses the

brain, and the 14 irregularly shaped acial bones (Fig. 2-52). T e inner and outer compact tables o the cranial skull are separated by cancellous tissue called diploe. T e internal table has a number o branching meningeal grooves and larger sulci that house blood vessels. T e bones o the skull are separated by immovable (synarthrotic) joints called sutures. T e major sutures o the cranium are the sagittal, which separates the parietal bones; the coronal, which separates the rontal and parietal bones; the lambdoidal, which separates the parietal and occipital bones; and the squammosal, which separates the temporal and parietal bones. T e sagittal and coronal sutures meet at the bregma, which corresponds to the etal anterior ontanel. T e

End of s pina l cord a t L2 Lumba r puncture ne e dle

S a cra l a ne s the s ia ne e dle

Figure 2-51. Reproduced with, permission from, Waxman: Correlative Neuroanatomy, 24th ed. 2000. McGraw-Hill, Inc. p. 75; Fig. 6-11.

Answers: 67–74 Pa rie ta l S qua mos a l bone s uture Te mpora l bone

91

Bre gma Corona l s uture Fronta l bone P te rion

As te rion

Gre a te r wing of s phe noid

La mbda

Gla be lla

La mbdoida l s uture

Na s ion

Occipita l bone

Na s a l bone La crima l bone

Exte rna l occipita l protube ra nce

Ethmoid bone Zygoma tic bone

Exte rna l a cous tic me a tus

Ante rior na s a l s pine Ma xilla Ma s toid proce s s S tyloid proce s s Zygoma tic a rch Angle of ma ndible

Ma ndible

Figure 2-52.

sagittal and lambdoidal sutures meet posteriorly at the lambda, which corresponds to the etal posterior ontanel. T e parietal, rontal, and sphenoid bones meet at the pterion, the location o the anterolateral ontanel. T e highest point o the skull is called the vertex. 71. (D) A right scapular Y is illustrated; this re ers to the characteristic Y ormed by the clearly visible humerus, acromion, and coracoid. T e patient is positioned in a PA oblique position—in this case, an RAO projection to demonstrate the right side. T e MCP is adjusted to approximately 60 degrees to the IR, and the a ected arm is le relaxed at the patient’s side. T e scapular Y position is employed to demonstrate anterior or posterior humeral dislocation. T e humerus is superimposed on the scapula in this position; any deviation rom this may indicate dislocation. 72. (B) ypically, traumatic injury to the hip requires a cross-table (axiolateral) lateral projection, as well as an AP projection o the entire pelvis. Both o these are per ormed using minimal manipulation o the a ected extremity, reducing the possibility o

urther injury. A physician should per orm any required manipulation o the traumatized hip. 73. (C) T e 45-degree oblique projection o the lumbar spine generally is per ormed or demonstration o the zygapophyseal joints. In a correctly positioned oblique lumbar spine, “Scotty dog” images are demonstrated (Figs. 2-53 and 2-54). T e Scotty’s ear corresponds to the superior articular process, his nose to the transverse process, his eye to the pedicle, his neck to the pars interarticularis, his body to the lamina, and his ront leg to the in erior articular process. 74. (D) An injury to a structure located on the side opposite o the primary injury is called a contrecoup injury. For example, a blow to the back o the head will injure rontal and temporal lobes because they are orced orward against the irregularly shaped bones o the anterior cranial vault. Blowout ractures occur to the oor o the orbit on a direct blow. A Le Fort racture involves severe bilateral maxillary ractures. Contracture re ers to shortening o muscle bers.

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the IR. T e a ected oot is dorsi exed so as to place its plantar sur ace 15 to 20 degrees with the vertical. T e CR is directed perpendicular to the posterior sur ace o the oot (near the metatarsophalangeal joints). T e dorsoplantar and oblique projections o the oot will demonstrate the sesamoid bones superimposed on adjacent bony structures.

Figure 2-53.

75. (B) T e tangential projection projects the sesamoid bones separate rom adjacent structures. T e patient is best examined in the prone position because this places the parts o interest closest to

76. (B) Osgood–Schlatter disease is most common in adolescent boys, involving osteochondritis o the tibial tuberosity epiphysis. T e large patellar tendon actually will pull the tibial tuberosity away rom the tibia. Immobilization generally will resolve the issue. Ewing sarcoma is a malignant bone tumor most common in young children. It attacks long bones and presents a characteristic “onion peel” appearance. Gout is a type o arthritis that most commonly attacks the knee and rst metatarsophalangeal joint, although other joints also can be involved. High levels o uric acid in the blood are deposited in the joint. Exostosis is a bony growth arising rom the sur ace o a bone and growing away rom the joint. It is a benign and sometimes pain ul condition. 77. (C) A er orce ul eversion or inversion injuries o the ankle, AP stress studies are valuable to con rm the presence o a ligament tear. Keeping the ankle in an AP position, the physician guides the ankle into inversion and eversion maneuvers. Characteristic changes in the relationship o the talus, tibia, and bula will indicate ligament injury. Inversion stress demonstrates the lateral ligament, whereas eversion stress demonstrates the medial ligament. A ractured ankle would not be manipulated in this manner. 78. (C) T e bony thorax consists o 12 pairs o ribs and the structures to which they are attached anteriorly and posteriorly: the sternum (consisting o manubrium, body/gladiolus, and xiphoid/ensiorm process) and the 12 thoracic vertebrae (Fig. 2-55). T ese structures orm a bony cage that surrounds and protects the vital organs within (the heart, lungs, and great vessels). T e scapulae, together with the clavicles, orm the shoulder (pectoral) girdle o the upper extremity.

Figure 2-54. Courtesy of Stamford Hospital, Department of Radiology.

79. (A) Because the right main stem bronchus is wider and more vertical, aspirated oreign bodies are more likely to enter it than the le main stem bronchus, which is narrower and angles more sharply rom the trachea. An aspirated oreign body does not enter

Answers: 75–83

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Firs t thora cic ve rte bra Ma nubrium Cos tochondra l junction S te rna l a ngle 1 Body of rib

Body of s te rnum

2 3

Xiphoid proce s s 4 Ante rior a ngle of rib

5 6 T10 7 T11 8

T12

9 12 He a d of rib

Inte rcos ta l ca rtila ge of ribs 6, 7, 8, 9, a nd 10

10 11

Ante rio r view

Figure 2-55.

the esophagus or the stomach because they are not respiratory structures. T e esophagus and stomach are digestive structures; a oreign body would most likely be swallowed to enter these structures. 80. (B) A PA projection o the chest is shown. T e shoulders are rolled orward, removing the scapulae rom the lung elds. Rotation o the chest is demonstrated by the unequal distance between the sternum and medial extremities o the clavicles. Adequate inspiration is not demonstrated because 10 posterior ribs are not visualized above the diaphragm. Pulmonary apices and costophrenic angles are demonstrated adequately. An air- lled trachea is seen in the lower cervical and upper thoracic region as an area o increased density. Adequate long-scale contrast has been achieved, as indicated by visualization o pulmonary vascular markings. 81. (C) A PA projection o the chest is shown. Adequate inspiration is demonstrated by visualization o 10 posterior ribs above the diaphragm. Rotation o the chest is demonstrated by asymmetrical

sternoclavicular joints. T e apices and costophrenic angles should be included on every chest radiograph. T e letter A indicates a le posterior rib, B represents a le anterior rib, and C represents the right costophrenic angle. 82. (C) T e axial trauma lateral (Coyle) position is described. I routine elbow projections in extension are not possible because o limited part movement, these positions can be used to demonstrate the coronoid process and/or radial head. With the elbow exed 90 degrees and the CR directed to the elbow joint at an angle o 45 degrees medially (i.e., toward the shoulder), the joint space between the radial head and capitulum should be revealed. With the elbow exed 80 degrees and the CR directed to the elbow joint at an angle o 45 degrees laterally (i.e., rom the shoulder toward the elbow), the elongated coronoid process will be visualized. 83. (B) Fibrous, or immovable (synarthrotic), articulations are tightly joined by brous connective tissue and have no joint cavity. T e articular sur aces in

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cartilaginous (amphiarthrotic) joints are held together by cartilage, o ering them little movement. Only synovial (diarthrotic, reely movable) joints possess a joint cavity, thus permitting them ree movement. Synovial type joints are the most numerous in the body.

several articulations should be demonstrated—the articulations between the talus and the navicular, between the calcaneus and the cuboid, between the cuboid and the bases o the ourth and h metatarsals, and between the cuboid and the lateral (third) cunei orm.

84. (C) I the x-ray photons can pass through/between structures such as joint spaces and oramina, these joint spaces and oramina must be situated perpendicular to the IR and parallel to the CR. T e intervertebral oramina o the thoracic and lumbar vertebrae are perpendicular to the IR and, thereore, parallel to the CR in the lateral projection. T e cervical intervertebral oramina are well demonstrated when placed 45 degrees to the IR and CR.

90. (B) T e AP projection o the radius and ulna in Fig. 2-16 has anatomical eatures numbered rom 1 to 12. 1: radial tuberosity, 2: neck o radius, 3: head o radius, 4: proximal radioulnar joint, 5: radius, 6: ulna, 7: base o h metacarpal, 8: lunate, 9: styloid process o ulna, 10: head o ulna, 11: scaphoid, 12: radial styloid process.

85. (A) T e dome o the acetabulum lies midway between the ASIS and the symphysis pubis. On an adult o average size, a line perpendicular to this point will parallel the plane o the emoral neck. In an AP projection o the hip, the CR should be directed to a point approximately 2 in down that perpendicular line so as to enter the distal portion o the emoral head. 86–87. (86, C; 87, D) Figure 2-14 illustrates an anatomic lateral view o the paranasal sinuses. Number 1 points to the rontal sinuses and number 2 to the ethmoidal sinuses; both can be visualized using the PA projection (Caldwell method). Number 3 is the sphenoidal sinuses, which are well demonstrated in the SMV projection. Number 4 is the maxillary sinuses, which are best demonstrated using the parietoacanthal projection (Waters’ method). T e lateral projection demonstrates the our groups o paranasal sinuses superimposed on each other. 88. (D) Hysterosalpingography may be per ormed or demonstration o uterine tubal patency, mass lesions in the uterine cavity, and uterine position. Although hysterosalpingography is o en perormed to check tubal patency, the uterine anatomy, position, and morphology are also exhibited. In addition, polyps, broids, or space-occupying lesions within the uterus are well demonstrated. 89. (C) T e radiograph shown is a medial oblique oot. With the oot rotated medially so that the plantar sur ace orms a 30-degree angle with the IR, the sinus tarsi, the tuberosity o the h metatarsal, and

91. (B) Lumbar articular acets, orming the zygapophyseal joints, are demonstrated in the oblique position. L1 through L4 are best demonstrated in a 45-degree oblique, while L5–S1 are best seen in the 30-degree oblique. T e AP axial projection is used to demonstrate an AP projection o L5–S1. 92. (B) Chest positioning must be correct and accurate; thoracic structures are easily distorted. o avoid superimposition on the upper medial apices, the patient’s chin should be suf ciently elevated. Movement o the diaphragm to its lowest position is a unction o the erect position and o making the exposure a er the second inspiration. T e MSP is perpendicular to the IR in the PA projection and parallel to the IR in the lateral projection. T e position o the chin has little to do with the MSP. 93. (B) Long bones are composed o a body/sha , or diaphysis, and two extremities. T e diaphysis is the primary ossi cation center. In the growing bone, the cartilaginous epiphyseal plate (located at the extremities o long bones) is gradually replaced by bone. T e epiphyses are re erred to as the secondary ossi cation centers. T e wider portion o bone adjacent to the epiphyseal plate is the metaphysis— that portion o long bone where lengthening/bone growth takes place. Apophysis re ers to a bony projection without an independent ossi cation center. 94. (A) A rontal projection (AP or PA) demonstrates the medial and lateral relationships o structures. A lateral projection demonstrates the anterior and posterior relationships o structures. wo views, at right angles to each other, generally are taken o most structures.

Answers: 84–102

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arteries bi urcate into internal and external carotid arteries at the level o C4. T e oramen magnum and pharynx are superior to the level o bi urcation, and the larynx is in erior to the level o bi urcation.

Figure 2-56.

95. (B) T e 45-degree oblique projection o the lumbar spine generally is per ormed or demonstration o the zygapophyseal joints. In a correctly positioned oblique lumbar spine, “Scotty dog” images are demonstrated. T e Scotty’s ear corresponds to the superior articular process, his nose to the transverse process, his eye to the pedicle, his neck to the pars interarticularis, his body to the lamina, and his ront oot to the in erior articular process (Fig. 2-56). 96. (D) T e illustration shows the patient positioned on his le side with the IR behind his back. T is is a le lateral decubitus position. T e x-ray beam is directed horizontally in decubitus positions to demonstrate air– uid levels. Air or uid levels will be clearly delineated only i the CR is directed parallel to them. Fluid levels will be best detected on the down side (in this case, le ); air levels will be best detected on the up side (in this case, right). I the patient were lying on the right side, it would be a right lateral decubitus position. I the patient were lying on his or her back with a horizontal x-ray beam, it would be a dorsal decubitus position. Lying prone with a horizontal x-ray beam is termed a ventral decubitus position. 97. (C) In the AP projection, the proximal bula is at least partially superimposed on the lateral tibial condyle. Medial rotation o 45 degrees will “open” the proximal tibio bular articulation. Lateral rotation will obscure the articulation even more. 98. (D) T e common carotid arteries unction to supply oxygenated blood to the head and neck. Major branches o the common carotid arteries (internal carotids) unction to supply the anterior brain, whereas the posterior brain is supplied by the vertebral arteries (branches o the subclavian). T e carotid

99. (B) A right lateral decubitus position will demonstrate a double-contrast visualization o le -sided bowel structures, that is, the lateral side o the descending colon and the medial side o the ascending colon. A le lateral decubitus position will demonstrate a double-contrast visualization o right-sided bowel structures, that is, the lateral side o the ascending colon and the medial side o the descending colon. With the patient in the erect position, barium moves in eriorly and air rises to provide double-contrast visualization o the hepatic and splenic exures. 100. (C) T e image is a transthoracic lateral projection o the proximal humerus, most o en used to in trauma situations. T e a ected humerus is adjacent to the image receptor, the una ected arm is elevated. T e proximal humerus and shoulder joint are projected and visualized through the thorax. T e una ected shoulder is elevated as much as possible to avoid superimposition on the a ected shoulder. I suf cient elevation o the una ected shoulder is not possible, the CR can be directed cephalad 10 to 15 degrees. T e use o “breathing technique” can urther improve visualization o the proximal humerus, as seen in the current image. 101. (B) o avoid the possibility o rotation, weight should be evenly distributed on the eet. T e chin should be elevated/extended in order to prevent its superimposition on pulmonary apices. T e shoulders should be depressed and rolled orward in order to remove the scapula rom the lung elds. In addition, in the case o large pendulous breasts, the patient should be requested to li and move them laterally be ore leaning against the upright mechanism. T e wellpositioned PA chest should demonstrate: scapulae away rom lung elds, medial aspect o sternoclavicular joints equidistant rom lateral aspect o adjacent vertebra, chin elevated away rom lung apices, inspiration adequate to demonstrate 10 posterior ribs. 102. (C) Hydronephrosis is a collection o urine in the renal pelvis owing to obstructed out ow, such as rom a stricture or obstruction. I the obstruction occurs at the level o the bladder or along the

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course o the ureter, it will be accompanied by the condition o hydroureter above the level o obstruction. T ese conditions may be demonstrated during IVU. T e term pyelonephrosis re ers to some condition o the renal pelvis. Nephroptosis re ers to drooping or downward displacement o the kidneys. T is may be demonstrated using the erect position during IVU. Cystourethritis is in ammation o the bladder and urethra. 103. (C) All traumatic injuries require the radiographer to be particularly alert and observant. Patient status must be observed and monitored continually. T e radiographer must speak calmly to the patient, explaining the procedure even i the patient appears unconscious or unresponsive. In the case o an injured limb, both joints must be supported i any movement is required. Both joints also must be included when examining long bones. T e injured limb need not be placed in exact AP and lateral positions, but any two views o the part at right angles to each other must be obtained. 104. (C) Perhaps the most important prerequisite to a success ul BE examination is a thoroughly clean large bowel. Any retained ecal material can simulate or obscure pathology. A single-contrast examination demonstrates the anatomy and contour o the large bowel, as well as anything that may project out rom the bowel wall (e.g., diverticula). In a double-contrast examination, the bowel wall (mucosa) is coated with barium, and then the lumen is lled with air. T is enables visualization o any intraluminal lesions such as polyps and tumor masses. 105. (D) o better visualize the joint space in the lateral projection o the knee, 20 to 30 degrees o exion is recommended. T e emoral condyles are superimposed so as to demonstrate the patello emoral joint and the articulation between the emur and the tibia. T e head o the bula will be slightly superimposed on the proximal tibia. T e correct degree o orward or backward body rotation is responsible or visualization o the patello emoral joint. Cephalad tube angulation o 5 to 7 degrees is responsible or demonstrating the articulation between the emur and the tibia (by removing the magni ed medial emoral condyle rom superimposition on the joint space). 106. (B) T ere are three important at pads associated with the elbow. T e anterior at pad is located just

anterior to the distal humerus. T e posterior at pad is located within the olecranon ossa at the distal posterior humerus. T e supinator at pad/stripe is located at the proximal radius just anterior to the head, neck, and tuberosity. T e posterior at pad is not visible radiographically in the normal elbow. All three at pads can be demonstrated only in the lateral projection o the elbow. 107. (B) Hematemesis is the presence o blood in vomit—this can occur with gastric ulcers, gastritis, esophageal varices, and other conditions. T e expectoration o blood rom the larynx, trachea, bronchi, or lungs is termed hemoptysis. Hemoptysis can occur in several diseases, including pneumonia, bronchitis, pulmonary tuberculosis, and others. 108. (D) Double-contrast studies o the stomach or large intestine involve coating the organ with a thin layer o barium sul ate and then introducing air. T is allows the operator to see through the organ to structures behind it and, most especially, allows visualization o the mucosal lining o the organ. A barium- lled stomach or large bowel demonstrates the position, size, and shape o the organ and any lesion that projects out rom its walls, such as diverticula. Polypoid lesions, which project inward rom the wall o an organ, may go unnoticed unless a double-contrast examination is per ormed. 109. (C) T e external rotation position is the true AP position and places the greater tubercle in pro le laterally and places the lesser tubercle anteriorly. T e internal rotation position demonstrates the lesser tubercle in pro le medially and places the humerus in a true lateral position; the greater tubercle is seen superimposed on the humeral head. T e epicondyles should be superimposed and perpendicular to the IR. T e neutral position places the epicondyles about 45 degrees to the IR and places the greater tubercle anteriorly but still lateral to the lesser tubercle. 110. (C) A PA projection o the hand is seen with seven anatomical eatures illustrated. Number 1 indicates the triquetrum; number 2 is the pisi orm; number 3 is the base o the h metacarpal; number 4 is the head o the h metacarpal; number 5 is the h metacarpophalangeal joint; number 6 is the h proximal interphalangeal joint; number 7 is the h distal interphalangeal joint.

Answers: 103–117

111. (C) T e external rotation position is the true AP position and places the greater tubercle in pro le laterally and places the lesser tubercle anteriorly. T e internal rotation position demonstrates the lesser tubercle in pro le medially and places the humerus in a true lateral position; the greater tubercle is seen superimposed on the humeral head. T e epicondyles should be superimposed and perpendicular to the IR. T e neutral position places the epicondyles about 45 degrees to the IR and places the greater tubercle anteriorly but still lateral to the lesser tubercle. 112. (C) T e PA axial projection (Camp-Coventry method) o the intercondyloid ossa (tunnel view) is shown. T e knee is exed about 40 degrees, and the CR is directed caudally 40 degrees and perpendicular to the tibia (Fig. 2-57). T e patella and patello emoral articulation are demonstrated in the axial/tangential view o the patella. 113. (C) T e parietoacanthal projection (Waters’method) demonstrates a distorted view o the rontal and ethmoidal sinuses. T e maxillary sinuses (number 4) are well demonstrated, projected ree o the petrous pyramids. T is is also the best single position or the demonstration o acial bones. T e mandibular angle is illustrated by the number 1, the zygomatic arch by number 2, and the coronoid process by number 3. 114. (C) Diarthrotic, or synovial, joints are reely movable. Most diarthrotic joints are associated with a joint capsule containing synovial uid. Diarthrotic joints are the most numerous in the body and are

subdivided according to the type o movement. Classi cations o diarthrotic joints include plane/ gliding, trochoid/pivot, ginglymus/hinge, spheroid/ball and socket, ellipsoid/condyloid, sellar/ saddle, and bicondylar/modi ed hinge. Amphiarthrotic (cartilaginous) joints are partially movable joints whose articular sur aces are connected by cartilage, such as intervertebral joints. Synarthrotic brous joints, such as the cranial sutures and gomphosis (roots o teeth), are immovable. 115. (C) T e carpal scaphoid is somewhat curved and consequently oreshortened radiographically in the PA position. o better separate it rom the adjacent carpals, the ulnar exion (ulnar deviation) maneuver is employed requently. In addition to correcting oreshortening o the scaphoid, ulnar exion/deviation opens the interspaces between adjacent lateral carpals. Radial exion/deviation is used to better demonstrate medial carpals. 116. (B) T e gure shows an AP projection o the shoulder. A plane passing through the epicondyles is parallel to the IR (and perpendicular to the CR). o project the coracoid process with less sel superimposition, the CR must be angled cephalad 15 degrees. T e amount o cephalad angulation depends on the degree o thoracic kyphosis; the greater the degree o kyphosis, the greater is the degree o cephalad angulation required. A 30-degree angle is used or the average patient. 117. (B) T e typical vertebra has a body and a neural/ vertebral arch surrounding the vertebral oramen (Fig. 2-58). T e neural arch is composed o two pedicles and two laminae that support our articular

S upe rior a rticula r proce s s

La mina

S pinous proce s s

Tra ns ve rs e proce s s

Pe dicle

Infe rior a rticula r proce s s

Ve rte bra l ca na l fora me n Body S e c o nd lumbar ve rte bra (s upe rio r view)

Figure 2-57.

97

Figure 2-58.

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processes, two transverse processes, and one spinous process. T e pedicles are short, thick processes extending back rom the posterior aspect o the vertebral body, each one sustaining a lamina. T e laminae extend posteriorly to the midline and join to orm the spinous process. Each pedicle has notches superiorly and in eriorly (superior and in erior vertebral notches) that – with adjacent vertebrae – orm the intervertebral oramina, through which the spinal nerves pass. T e neural arch also has lateral transverse processes or muscle attachment and superior and in erior articular processes or the ormation o zygapophyseal joints (classi ed as diarthrotic). T e vertebral column permits exion, extension, and lateral and rotary motions through its various articulations. 118. (B) T e type o racture in which the splintered ends o bone are orced through the skin is a compound racture. In a closed racture, no bone protrudes through the skin. Compression ractures are seen in stressed areas, such as the vertebrae. A depressed racture would not protrude but rather would be pushed in. 119. (D) T e thoracic zygapophyseal joints are demonstrated in an oblique position with the coronal plane 70 degrees to the IR (MSP 20 degrees to the IR). T is may be accomplished by rst placing the patient lateral and then obliquing the patient 20 degrees “o lateral.” T e zygapophyseal joints closest to the IR are demonstrated in the PA oblique projection and those remote rom the IR in the AP oblique projection. Comparable detail is obtained using either method because the OID is about the same. T e thoracic intervertebral oramina are demonstrated in the lateral projection. T is places the MSP o the patient parallel to the IR, and the coronal plane perpendicular to the IR. 120. (B) Electronic imaging (CR and DR) uses highly sensitive image-capture devices. Consideration must be given to the SR emerging rom the patient and striking the IR. o reduce the amount o SR that reaches the IR, the x-ray beam should be tightly collimated, and a lead mat should be placed on the x-ray table just posterior to the patient’s lumbosacral area. T e x-ray photons that would have extended posterior to the patient’s skin and simply struck the x-ray table – causing increased SR to reach the IR – will be absorbed by the lead mat. T e SID is unrelated to scattered radiation production.

121. (C) T e typical vertebra has two parts—the body and the vertebral arch. T e body is the dense, anterior bony mass. Posteriorly attached is the vertebral arch, a ring-like structure. T e vertebral arch is ormed by two pedicles (short, thick processes projecting posteriorly rom the body) and two laminae (broad, at processes projecting posteriorly and medially rom the pedicles). 122. (B) Obstruction o the small bowel is termed ileus; there are two types o ileus—paralytic/adynamic and mechanical. Paralytic or adynamic ileus is characterized by an absence o peristalsis. T is can be caused by in ection (e.g., appendicitis or peritonitis) or postoperative dif culty. Mechanical ileus is caused by some sort o physical obstruction such as tumor or adhesions. 123. (D) T e tangential projection o the wrist, GaynorHart method demonstrates the carpal canal and several carpals/portions o carpals. T is position can be used to evaluate compression o median nerve and to detect carpal ractures. AP oblique hands/ Norgaard Method, o en re erred to as the ballcatcher’s position, is used to detect evidence o early rheumatoid arthritis. Radial deviation o the wrist is used to demonstrate medial carpals and their articulations. T e PA axial projection wrist, Stecher method, is used to demonstrate scaphoid racture. 124. (A) Croup is a viral in ection generally seen in children 1 to 3 years o age. It is characterized by a dry cough, sometimes accompanied by ever. So tissue projections o the neck are requently used to evaluate the upper airway. Narrowing o the upper airway is best demonstrated in the AP projection. 125. (A) T ere are ve used sacral vertebrae; the used transverse processes orm the alae. T e anterior and posterior sacral oramina transmit spinal nerves. T e sacrum articulates superiorly with the h lumbar vertebra, orming the L5–S1 articulation, and in eriorly with the coccyx, orming the sacrococcygeal joint. T e sacrum curves posteriorly and in eriorly, whereas the coccyx curves anteriorly; thus, they require di erent tuble angles to “open them up.” Image A demonstrates an AP axial projection o the sacrum with CR angulation o 15 degrees cephalad. Image B is an AP axial projection o the coccyx using the required 10-degree caudal CR angle.

Answers: 118–136

126. (D) T e our types o body habitus describe di erences in visceral shape, position, tone, and motility. One body type is hypersthenic, characterized by the very large individual having short and wide heart and lungs, and high transverse stomach. T e hyperstatic habitus also has a high horizontal gallbladder and peripheral colon. T e sthenic individual is the average, athletic, most predominant type. T e hyposthenic patient is somewhat thinner and a little railer, with organs positioned somewhat lower. T e asthenic type is smaller in the extreme, with a long thorax, a very long, almost pelvic stomach, and a low medial gallbladder. T e colon is medial and redundant. Hypersthenic patients usually demonstrate the greatest motility. 127. (C) When a cervical spine radiograph is requested to rule out subluxation or racture, the patient will arrive in the radiology area on a stretcher. T e patient should not be moved be ore a subluxation is ruled out. Any movement o the head and neck could cause serious damage to the spinal cord. A horizontal beam lateral projection is per ormed and evaluated. T e physician then will decide what urther images are required. 128. (D) T e term proximal re ers to structures closer to the point o attachment. For example, the elbow is described as being proximal to the wrist; that is, the elbow is closer to the point o attachment (the shoulder) than is the wrist. Re erring to the question, then, the interphalangeal joints (both proximal and distal) and the metacarpals are both distal to the carpal bones. T e radial styloid process is proximal to the carpals. 129. (C) T e scapular Y projection requires that the coronal plane be about 60 degrees to the IR (MSP is about 30 degrees), thus resulting in an oblique projection o the shoulder. T e vertebral and axillary borders o the scapula are superimposed on the humeral sha , and the resulting relationship between the glenoid ossa and humeral head will demonstrate anterior or posterior dislocation. Lateral or medial dislocation is evaluated on the AP projection. 130. (C) T e articular acets (zygapophyseal joints) o the L5–S1 articulation orm a 30-degree angle with the MSP; they are, there ore, well demonstrated in a 30-degree oblique position. T e 45-degree

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oblique position demonstrates the zygapophyseal joints o L1–4. 131. (B) T e pharynx is the portion o the elementary canal continuous with the oral cavity. Its three portions, rom proximal to distal, are: the nasopharynx, the oropharynx, and the laryngopharynx. T e laryngopharynx is then continuous with the esophagus. T e epiglottis covers the airway/laryngeal opening during swallowing. 132. (B) With the patient in the PA position, the rami are well visualized with a perpendicular ray or with 20 to 25 degrees o cephalad angulation. A portion o the mandibular body is demonstrated in this position, but most o it is superimposed over the cervical spine. 133. (B) T e kidneys lie obliquely in the posterior portion o the trunk with their superior portion angled posteriorly and their in erior portion and ureters angled anteriorly. T ere ore, to acilitate lling o the most anteriorly placed structures, the patient is examined in the prone position. Opaci ed urine then ows to the most dependent part o the kidney and ureter—the ureteropelvic region, in erior calyces, and ureters. 134. (B) T e median sagittal, or midsagittal, plane (MSP) passes vertically through the midline o the body, dividing it into le and right halves. Any plane parallel to the MSP is termed a sagittal plane. T e midcoronal plane is perpendicular to the MSP and divides the body into anterior and posterior halves. A transverse plane passes through the body at right angles to a sagittal plane. T ese planes, especially the MSP, are very important re erence points in radiographic positioning (Fig. 2-59). 135. (A) In an AP projection o the shoulder, there is superimposition o the humeral head and glenoid ossa. With the patient obliqued 45 degrees toward the a ected side, the glenohumeral joint is open, and the glenoid ossa is seen in pro le. T e patient’s arm is abducted somewhat and placed in internal rotation. 136. (B) T e radiograph shown illustrates an AP projection o the lumbar spine. T e intervertebral disk spaces (number 3) are well visualized because the patient’s knees were exed with eet at on the

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Midcoronal plane

Midsagittal plane

Transverse plane

Pos t e rio r An te r

io r

Figure 2-59.

table. Number 2 points out the body/spinous process o the rst lumbar vertebrae; number 4 is the transverse process o L3. Number 1 indicates the right 12th rib. Number 5 indicates the well-de ned margins o the psoas muscle. 137. (A) During a double-contrast BE, barium and air will distribute themselves according to the position o parts o the colon within the body and according to body position. When the body is in the AP recumbent position, the most anterior structures will be air lled. Anterior structures include the transverse colon and a portion o the sigmoid colon. Both exures would be air lled in the erect position. 138. (C) I structures are overlying or underlying the area to be demonstrated (e.g., the medial emoral condyle obscuring the joint space in the lateral knee projection), CR angulation is used (e.g., 5-degree cephalad angulation to see the joint space in the lateral knee).

I structures are likely to be oreshortened or sel -superimposed (e.g., the scaphoid in a PA wrist), CR angulation may be employed to place the structure more closely parallel with the IR. Another example is the oblique cervical spine, where cephalad or caudad angulation is required to “open” the intervertebral oramina. Magni cation is controlled by object-toimage-receptor distance (OID) and SID; it is unrelated to CR angulation. 139. (C) In the dorsoplantar projection o the oot, the CR may be directed perpendicularly or angled 10 degrees posteriorly. Angulation serves to “open” the tarsometatarsal joints that are not well visualized on the dorsoplantar projection with perpendicular ray. Inversion and eversion o the oot do not a ect the tarsometatarsal joints. 140. (C) o accurately position a lateral orearm, the elbow must orm a 90-degree angle with the

Answers: 137–145

humeral epicondyles perpendicular to the IR and superimposed. T e radius and ulna are superimposed distally. Proximally, the coronoid process and radial head are superimposed, and the radial head aces anteriorly. Failure o the elbow to orm a 90-degree angle or the hand to be lateral results in a less than satis actory lateral projection o the orearm. 141. (A) T e routine AP projection o the lumbar spine demonstrates the intervertebral disk spaces between the rst our lumbar vertebrae. T e space between L5 and S1, however, is angled with respect to the other disk spaces. T ere ore, the CR must be directed 30 to 35 degrees cephalad to parallel the disk space and thus project it open onto the IR. 142. (C) A certain amount o object unsharpness is an inherent part o every radiographic image because o the position and shape o anatomic structures within the body. Structures within the threedimensional human body lie in di erent planes. In addition, the three-dimensional shape o solid anatomic structures rarely coincides with the shape o the divergent beam. Consequently, some structures are imaged with more inherent distortion than others, and shapes o anatomic structures can be entirely misrepresented. Structures arther rom the IR will be distorted (i.e., magni ed) more than those closer to the IR; structures closer to the x-ray source will be distorted (i.e., magni ed) more than those arther rom the x-ray source. For the shape o anatomic structures to be accurately recorded, the structures must be parallel to the x-ray tube and the IR, and aligned with the central ray (CR). T e shape o anatomic structures lying at an angle within the body or placed away rom the CR will be misrepresented on the IR. T ere are two types o shape distortion. I a linear structure is angled within the body, that is, not parallel with the long axis o the part/body and not parallel to the IR, then that anatomic structure will appear smaller—it will be oreshortened. On the other hand, elongation occurs when the x-ray tube is angled. Image details placed away rom the path o the CR will be exposed by more divergent rays, resulting in rotation distortion. T is is why the CR must be directed to the part o greatest interest. Unless the edges o a three-dimensional object con orm to the shape o the x-ray beam, blur or unsharpness will occur at the partially attenuating

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edge o the object. T is can be accompanied by changes in radiographic/image density, according to the thickness o areas traversed by the x-ray beam. 143. (C) Patients are instructed to remove all jewelry, hair clips, metal prostheses, coins, and credit cards be ore entering the room or MRI. MRI does not use radiation to produce images but instead uses a very strong magnetic eld. All patients must be screened prior to entering the magnetic eld to be sure that they do not have any metal on or within them. Proper screening includes questioning the patient about any eye injury involving metal, cardiac pacemakers, aneurysm clips, insulin pumps, heart valves, shrapnel, or any metal in the body. T is is extremely important, and i there is any doubt, the patient should be rescheduled or a time a er it has been determined that it is sa e or him or her to enter the room. Patients who have done metalwork or welding are requently sent to diagnostic radiology or screening images o the orbits to ensure that there are no metal ragments near the optic nerve. Any external metallic objects, such as bobby pins, hair clips, or coins in the pocket, must be removed, or they will be pulled by the magnet and can cause harm to the patient. Credit cards and any other plastic cards with a magnetic strip will be wiped clean i they come in contact with the magnetic eld. 144. (C) A lateral projection generally is included in a routine skull series. T e patient is placed in a PA oblique position. T e MSP is positioned parallel to the IR, and the IOML is adjusted so as to be parallel to the long axis o the IR. T e interpupillary line must be perpendicular to the IR. In a routine lateral projection o the skull, the CR should enter approximately 2 in superior to the EAM. 145. (B) T e radiograph shown in Figure 2-25 is a prone recumbent projection. I the patient were in the supine recumbent position, barium would be located in the undus o the stomach because the undus is more posterior, and barium would ow down to ll the posterior structure. I the patient were in the supine rendelenburg position, barium ow to the undus would be acilitated even more. I the patient were erect, air– uid levels would be clearly de ned. In addition, the barium- lled stomach tends to spread more horizontally in the prone position (as is seen in the radiograph).

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146. (B) T e lordotic curves are secondary curves; that is, they develop sometime a er birth. T e cervical and lumbar vertebrae orm lordotic curves. T e thoracic and sacral vertebrae exhibit the primary kyphotic curves, those that are present at birth.

caused by separation or dislocation. Weights should be anchored rom the patient’s wrists rather than held in the patient’s hands because this encourages tightening o the shoulder muscles and obliteration o any small separation.

147. (B) T e ngers must be supported parallel to the IR (e.g., on a nger sponge) in order that the joint spaces parallel the x-ray beam. When the ngers are exed or resting on the IR, the relationship between the joint spaces and the IR changes, and the joints appear “closed.”

152. (A) Ewing sarcoma is a (primary) malignant bone tumor that arises rom bone marrow and occurs in children and young adults. T e disease is characterized by new bone ormation in a layering e ect—giving the bone the characteristic “onion peel” appearance radiographically. Multiple myeloma is also a cancerous bone tumor usually a ecting adults between the ages o 40 and 70 years. Bone undergoes osteolytic changes, and radiographic demonstration appears as circular areas o bone loss. As their name implies (chondr), enchondroma and osteochondroma involve cartilage—they are both benign conditions.

148. (C) Long bones are composed o a body/sha , or diaphysis, and two extremities. T e diaphysis is the primary ossi cation center. In the growing bone, the cartilaginous epiphyseal plate (located at the extremities o long bones) is gradually replaced by bone. T e epiphyses are re erred to as the secondary ossi cation centers. T e wider portion o bone adjacent to the epiphyseal plate is the metaphysis— that portion o long bone where lengthening/bone growth takes place. Apophysis re ers to a bony projection without an independent ossi cation center. 149. (A) T e position o the gallbladder varies with the body habitus o the patient. Hypersthenic patients are more likely to have their gallbladder located high and lateral. T e asthenic patient’s gallbladder is most likely to occupy a low and medial position, occasionally superimposed on the vertebrae or iliac ossa. T e LAO position is used most o en to move the gallbladder away rom the spine. T e erect position would make the gallbladder move even more in erior and medial. 150. (A) T e abdomen is divided into nine regions. T e upper lateral regions are the le and right hypochondriac, with the epigastric separating them. T e middle lateral regions are the le and right lumbar, with the umbilical region between them. T e lower lateral regions are the le and right iliac, with the hypogastric region between them. T e ileocecal valve, cecum, and appendix (i present) are located in the lower right abdomen—there ore, the right iliac region. 151. (B) Evaluation o the acromioclavicular joints requires bilateral AP or PA erect projections with and without the use o weights. Weights are used to emphasize the minute changes within a joint

153. (A) When the patient is recumbent with the head lower than the eet, he or she is said to be in the rendelenburg position. T e decubitus position is used to describe the patient who is recumbent (prone, supine, or lateral) with the CR directed horizontally. In the Fowler position, the patient’s head is positioned higher than the eet. T e Sim position is the (LAO) position assumed or enema tip insertion. 154. (D) T e SMV projection is made with the patient’s head resting on the vertex and the CR directed perpendicular to the IOML. T is position may be used as part o a sinus survey to demonstrate the sphenoidal sinuses or as a view o the cranial base or the basal oramina (especially the oramina ovale and spinosum). It also demonstrates the bony part o the auditory (eustachian) tubes. AP or PA axial projections are used requently to demonstrate the occipital region or evaluate the sellar region. A lateral projection is usually part o a routine skull evaluation. T e parietoacanthal projection is the single best position to demonstrate acial bones. 155. (B) T e radiograph in Figure 2-26 illustrates a lateral projection o the scapula. T e axillary and vertebral borders are superimposed. T e acromion and coracoid process are visualized; the coracoid process is partially superimposed on the axillary portion o the third rib. A scapular Y projection is o en per ormed to demonstrate shoulder dislocation, but the a ected arm is le to rest at the patient’s

Answers: 146–161

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side; the arm in this radiograph is abducted somewhat to better view the body o the scapula.

transverse process acet (number 9) to orm the costotransverse articulation (number 3).

156. (A) T e emur is the longest and strongest bone in the body. T e emoral sha is bowed slightly anteriorly and presents a long, narrow ridge posteriorly called the linea aspera. T e proximal emur consists o a head that is received by the pelvic acetabulum. T e emoral neck, which joins the head and sha , normally angles upward about 120 degrees and orward (in anteversion) about 15 degrees. T e greater and lesser trochanters are large processes on the posterior proximal emur. T e intertrochanteric crest runs obliquely between the trochanters; the intertrochanteric line parallels the intertrochanteric crest on the anterior emoral sur ace. T e intercondyloid ossa, a deep notch, is ound on the distal posterior emur between the large emoral condyles, and the popliteal sur ace is a smooth surace just superior to the intercondyloid ossa. Just opposite the popliteal sur ace, on the distal anterior emur is the patellar sur ace—a smooth sur ace or patellar motion during exion and extension o the knee.

159. (B) In a PA projection o the chest, there should be no rotation, as evidenced by symmetry o sternal extremities o clavicles equidistant rom vertebral borders. T e shoulders are rolled orward to remove the scapulae rom the lung elds. Inspiration should be adequate to demonstrate 10 posterior ribs above the diaphragm. T e air- lled trachea should be seen midline; the esophagus is unlikely to be visualized without a contrast agent.

157. (A) T e tangential axial projections o the patella are also o en re erred to as sunrise or skyline views. T e supine exion 45-degree (Merchant) position requires a special apparatus, and the patellae can be examined bilaterally. T is position also requires patient com ort without muscle tension—muscle tension can cause a subluxed patella to be pulled into the intercondyler sulcus, giving the appearance o a normal patella. T e two prone positions di er according to the degree o exion employed. T e 90-degree exion (Settegast) position must not be employed with suspected patellar racture. 158. (D) T e typical vertebra is divided into two portions—the (anterior) body (number 11) and the (posterior) vertebral arch. T e vertebral arch supports seven processes: two transverse (number 8), one spinous (number 1), two superior articular processes, and two in erior articular processes. A thoracic vertebra is shown. T e thoracic vertebrae are unique in that they have downward-angling spinous processes and articulations or ribs. Numbers 5 and 10 illustrate the acets where the heads o ribs (number 7) articulate to orm the costovertebral articulations (number 6). Number 2 illustrates the ribs’ tubercle—it articulates with the

160. (B) T e talocalcaneal, or subtalar, joint is a three- aceted articulation ormed by the talus and the os calcis (calcaneus). T e plantodorsal and dorsoplantar projections o the os calcis should exhibit suf cient density to visualize the talocalcaneal joint (Fig. 2-60). T is is the only “routine” projection that will demonstrate the talocalcaneal joint. I evaluation o the talocalcaneal joint is desired, special views (such as the Broden and Isherwood methods) are required. 161. (C) In a lateral projection o the ankle, the tibia and bula are superimposed, and the oot is somewhat dorsi exed to better demonstrate the talotibial joint. T e talo bular joint is not visualized because o superimposition with other bony structures. It may be well visualized in the medial oblique projection o the ankle.

Figure 2-60. Courtesy of Stamford Hospital, Department of Radiology.

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162. (B) A double-contrast examination o the large bowel is per ormed to see through the bowel to its posterior wall and to visualize any intraluminal lesions or masses. Oblique projections are used to “open up” the exures—the RAO or the hepatic exure and the LAO or the splenic exure. o view the redundant S-shaped sigmoid in the AP position, the CR is directed 30 to 40 degrees cephalad. T e CR is reversed when the patient is in the PA position; that is, the CR is directed 30 to 40 degrees caudad. 163. (C) Radiographic examinations o the large bowel generally include the AP or PA axial position to “open” the S-shaped sigmoid colon, the lateral position especially or the rectum, and the LAO and RAO (or LPO and RPO) positions to “open” the colic exures. T e le and right decubitus positions usually are employed only in double-contrast barium enemas to better demonstrate double contrast o the medial and lateral walls o the ascending and descending colon.

164. (D) Bilateral AP oblique hands are obtained using the Norgaard method or “Ball-Catcher position.” T e method is used to detect early rheumatoid arthritis changes or racture to the base o the h metacarpal. T e hands are positioned and supported in a 45-degree oblique, palm-up position. T e CR is directed to the level o the h metacarpophalangeal joint (MPJ) midway between the hands—both hands are exposed simultaneously. 165. (C) Venous blood is returned to the right atrium via the superior ( rom the upper body) and in erior ( rom the lower body) venae cavae (see Fig. 2-61). During atrial systole, blood passes rom the right atrium through the tricuspid valve into the right ventricle and rom the le atrium through the bicuspid/mitral valve into the le ventricle. During ventricular systole, the pulmonary artery (the only artery to carry deoxygenated blood) carries blood rom the right ventricle to the lungs or oxygenation, whereas the le ventricle moves oxygenated

S upe rior ve na cava (from he a d a nd a rms )

Aorta To lung

Right pulmona ry a rte ry

Le ft pulmona ry a rte ry To lung Le ft pulmona ry ve ins

Right pulmona ry ve ins

From lung

From lung

Le ft a trium Bicus pid (mitra l) va lve

P ulmona ry s e miluna r va lve

Aortic va lve

Right a trium Tricus pid va lve

Chorda e te ndine a e

Chorda e te ndine a e

Le ft ve ntricle

Infe rior ve na cava (from trunk a nd le gs ) Right ve ntricle

Figure 2-61.

Answers: 162–175

blood through the aortic semilunar valve into the aorta and to all body tissues. 166. (A) Visualization o the scapular spine (number 13) indicates that this is a view o the posterior aspect o the scapula. T e scapula’s anterior, or costal, sur ace is that which is adjacent to the ribs. T e scapula has no sternal articulation. 167–168. (167, C; 168, A) Figure 2-29 depicts a posterior view o the right scapula and its articulation with the humerus (number 4). T e scapula presents two borders—the lateral or axillary border (number 7) and the medial or vertebral border (number 9). It also presents three angles—the in erior angle (number 8), the superior angle (number 12), and the lateral angle (number 6). T e processes o the scapula are the coracoid (number 2), the acromion (number 3), and the scapular spine (number 13). T e scapula has a (supra) scapular notch (number 1), a supraspinatus ossa (number 11), and an in raspinatus ossa (number 10). Number 5 identi es the glenoid ossa—the articular sur ace or the humeral head, orming the glenohumeral articulation. 169. (C) For the PA projection o the skull, the OML is adjusted perpendicular to the IR, and the MSP must be perpendicular to the IR. T e CR is directed so as to exit the nasion. In this position, the petrous pyramids should completely ll the orbits. When caudal angulation is used with this position, the petrous pyramids are projected in the lower portion, or out o , the orbits. I cephalad angulation is used with this position, the petrous pyramids are projected up toward the occipital region (as in the nucho rontal projection). 170. (D) A PA axial projection o the skull with a 15-degree caudad angle will show the petrous pyramids in the lower third o the orbits. I no angulation is used, the petrous pyramids will ll the orbits. Either PA projection should demonstrate symmetrical petrous pyramids and an equal distance rom the lateral border o the skull to the lateral border o the orbit on both sides. T is determines that there is no rotation o the skull. 171. (A) T e AP oblique positions (RPO and LPO) demonstrate the colonic structures arther rom the IR. T e LPO position will demonstrate the hepatic exure and ascending colon, whereas the

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RPO position demonstrates the splenic exure and descending colon. In the prone oblique positions (RAO and LAO), the exure disclosed is the one closer to the IR. T ere ore, the LAO position will “open up” the le colic, or splenic, exure, and the RAO position will demonstrate the right colic, or hepatic, exure. 172. (D) Sur ace landmarks, prominences, and depressions are very use ul to the radiographer in locating anatomic structures that are not visible externally. T e costal margin is at about the same level as L3. T e umbilicus is at approximately the same level as the L3–4 interspace. T e xiphoid tip is at about the same level as 10. T e ourth lumbar vertebra is at approximately the same level as the iliac crest. 173. (B) T e position, shape, and motility o various organs can di er greatly rom one body habitus to another. T e hypersthenic individual is large and heavy; the lungs and heart are high, the stomach is high and transverse, the gallbladder is high and lateral, and the colon is high and peripheral. In contrast, the other habitus extreme is the asthenic individual. T is patient is slender and light and has a long and narrow thorax, a low and long stomach, a low and medial gallbladder, and a low medial and redundant colon. T e radiographer must consider these characteristic di erences when radiographing individuals o various body types. 174. (A) T e cervical intervertebral oramina lie 45 degrees to the MSP and 15 to 20 degrees to a transverse plane. When the anterior oblique position (LAO or RAO) is used, the cervical intervertebral oramina demonstrated are those closer to the IR. In the posterior oblique position (LPO or RPO), the oramina disclosed are those arther rom the IR. T ere is, there ore, some magni cation o the oramina in the posterior oblique positions. T e interarticular (zygapophyseal) joints and intervertebral joints are best visualized in the lateral projection. 175. (C) With inspiration, the diaphragm moves in eriorly and depresses the abdominal viscera. T e ribs and sternum are elevated. As the ribs are elevated, their angle is decreased. Radiographic density can vary considerably in appearance depending on the phase o respiration during which the exposure is made.

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176. (A) A lateral projection o the scapula superimposes its medial and lateral borders (vertebral and axillary, respectively). T e coracoid and acromion processes should be readily identi ed separately (not superimposed) in the lateral projection. T e entire scapula should be ree o superimposition with the ribs. T e erect position is probably the most com ortable position or a patient with scapular pain. 177. (D) T e image demonstrates the sternum made in the RAO position. Minimal rotation succeeds in projecting the sternum ree o superimposition with the vertebral column. T is position projects the sternum to the le side o the thorax. Superimposition o the sternum onto the heart and other mediastinal structures promotes more uni orm density. Exposure made during shallow respiration serves to obliterate pulmonary vascular markings. 178. (C) In the lateral projection o the knee, the joint space is obscured by the magni ed medial emoral condyle unless the CR is angled 5 to 7 degrees cephalad. T e degree o exion o the knee is important when evaluating the knee or possible transverse patellar racture. In such a case, the knee should not be exed more than 10 degrees. T e knee normally should be exed 20 to 30 degrees in the lateral position. 179. (A) T e AP axial projection o the cervical spine demonstrates the bodies and intervertebral spaces o the last ve vertebrae (C3–7). T e intervertebral oramina are 45 degrees to the MSP and there ore demonstrated in the oblique projection. T e cervical zygapophyseal joints are 90 degrees to the MSP and, are demonstrated in the lateral projection. 180. (B) T e base o the rst metacarpal, on the lateral side o the hand, articulates with the most lateral carpal o the distal carpal row, the trapezium/ greater multangular. T is articulation orms a rather unique and very versatile sellar/saddle joint named or the shape o its articulating sur aces. 181. (C) T e PA (Caldwell) projection o the paranasal sinuses is used to demonstrate the rontal and ethmoidal sinuses. T e patient’s skull is placed PA, and the OML is elevated 15 degrees rom the horizontal. T is projects the petrous pyramids into the lower third o the orbits, thus permitting optimal visualization o the rontal and ethmoidal sinuses.

182. (A) T e respiratory passageways include the nose, pharynx, larynx (upper respiratory structures), trachea, bronchi, and lungs (lower structures). I obstruction o the breathing passageways occurs in the upper respiratory tract, above the larynx (i.e., in the nose or pharynx), tracheotomy may be per ormed to restore breathing. Intubation can be done into the lower structures, larynx, and trachea, moving aside any so obstruction and restoring the breathing passageway. 183. (D) During GI radiography, the position o the stomach may vary depending on the respiratory phase, the body habitus, and the patient position. Inspiration causes the lungs to ll with air and the diaphragm to descend, thereby pushing the abdominal contents downward. On expiration, the diaphragm will rise, allowing the abdominal organs to ascend. Body habitus is an important actor in determining the size and shape o the stomach. An asthenic patient may have a long, J-shaped stomach, whereas the stomach o a hypersthenic patient may be transverse. T e body habitus is an important consideration in determining the positioning and placement o the IR. T e patient position also can alter the position o the stomach. I a patient turns rom the RAO position into the AP position, the stomach will move into a more horizontal position. Although the cardiac sphincter and the pyloric sphincter are relatively xed, the undus is quite mobile and will vary in position. 184. (B) Operative cholangiography can play a vital role in biliary tract surgery. T e contrast medium is injected, usually through the CBD, and images are usually made ollowing the cholecystectomy. T e procedure is used to investigate the patency o the bile ducts, the unction o the hepatopancreatic sphincter (o Oddi), and the presence o previously undetected biliary tract calculi. 185. (A) Lateral projections o the barium- lled stomach (Fig. 2-62) may be per ormed recumbent or upright or demonstration o the retrogastric space. With the patient in the (usually right) lateral position, the CR is directed to a point midway between the midcoronal line and the anterior sur ace o the abdomen at the level o L1. When the patient is in the LPO or RAO position, the CR should be directed midway between the vertebral column (MCP) and the anterior sur ace o the abdomen.

Answers: 176–192

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movement that should be permitted is movement o the entire spine, body, and head together, as in log-rolling. Any twisting could cause severe and permanent damage to the spinal cord, resulting in paralysis or even death. 188. (C) In the tangential (sunrise) projection o the patella, the CR is directed parallel to the longitudinal plane o the patella, thereby demonstrating a vertical racture and providing the best view o the patello emoral articulation. T e AP knee projection could demonstrate a vertical racture through the superimposed emur, but it does not demonstrate the patello emoral articulation. T e tunnel view o the knee is used to demonstrate the intercondyloid ossa.

Figure 2-62. Courtesy of Stamford Hospital, Department of Radiology.

For the PA projection, the CR is directed perpendicular to the IR at the level o L2. 186. (B) When injury requires that the elbow be examined in partial exion, the lateral projection o ers little dif culty, but the AP projection requires special attention. I the AP radiograph is made with a perpendicular CR and the olecranon process resting on the tabletop, the articulating sur aces are obscured. With the elbow in partial exion, two exposures are necessary. One is made with the orearm parallel to the IR (humerus elevated), which demonstrates the proximal orearm. T e other is made with the humerus parallel to the IR ( orearm elevated), which demonstrates the distal humerus. In both cases, the CR is perpendicular i the degree o exion is not too great or is angled slightly into the joint space with greater degrees o exion. 187. (C) When imaging a patient with a possible traumatic spine injury, it is appropriate to either maneuver the x-ray tube head or, i the patient must be moved, to use the log-rolling method. T is cannot be done by one person; the radiographer must summon assistance. I the patient is on a backboard and in a neck collar, as most patients with suspected spine injury are, it is never appropriate to ask the patient to turn, scoot, or slide over. T e only

189–190. (189, D; 190, A) T e radiograph shown is a lateral projection o the cervical spine taken in exion. Flexion and extension views are use ul in certain cervical injuries, such as whiplash, to indicate the degree o anterior and posterior motion. T e structure labeled number 1 is a zygapophyseal joint; because zygapophyseal joints orm a 90-degree angle with the MSP, they are well visualized in the lateral projection. T e structure labeled number 2 is a vertebral body. Numbers 3 through 6 are various components o C1 (atlas) and C2 (axis). T e large body o C2 (number 6) is has a process superiorly, the odontoid process/dens (number 4). T e odontoid process ts into, and articulates with C1. T e superimposed posterior arch o C1 is indicated by number 3. T e dens (number 4) is articulated with the anterior arch o C1 (number 5). 191. (C) T e voiding cystourethrogram (VCUG) is a unctional study per ormed to evaluate the physiology o urination to demonstrate possible vesicoureteral ref ux (backup o urine rom bladder into ureters, causing repeated urinary tract in ections). T e retrograde urogram and retrograde cystogram demonstrate the anatomy (not unction) o the urinary tract. T e intravenous/excretory urogram does demonstrate unction o the urinary tract but does not evaluate the urethra. 192. (B) T e AP projection o the clavicle should demonstrate the clavicular body/sha and its two extremities: the sternal extremity and its associated sternoclavicular articulation, and the acromial extremity and its associated acromioclavicular

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articulation. T e sternocostal joint is the articulation between the sternum and rib and is not delineated in the AP clavicle image. 193. (C) T e AP projection demonstrates superimposition o the distal bula on the talus; the joint space is not well seen. T e 15- to 20-degree medial oblique position shows the entire mortise joint; the talo bular joint is well visualized, as well as the talotibial joint. T ere is considerable superimposition o the talus and bula in the lateral and lateral oblique projections. 194. (A) T e erect position is employed most o en to demonstrate air– uid levels in the chest or abdomen or both. However, patients having traumatic injuries requently must be examined in the recumbent position. T e recumbent position will not demonstrate air– uid levels unless it is a decubitus position. I ree air is being questioned, we will look or that quantity o air on the “up” side because air rises. However, because liver tissue is so homogenous, a small amount o air will be perceived more easily superimposed on it rather than on le -sided structures. T us, an AP projection obtained in the le lateral decubitus position will best demonstrate a small amount o ree air because that air will be superimposed on the liver. 195. (A) Blood is oxygenated in the lungs and carried to the le atrium by the our pulmonary veins. From the le atrium, blood ows through the bicuspid (mitral) valve into the le ventricle. Blood leaving the le ventricle is bright red, oxygenated blood that travels through the systemic circulation, which delivers oxygenated blood via arteries and returns deoxygenated blood to the lungs via veins. From the le ventricle, blood rst goes through the largest arteries and then goes to progressively smaller arteries (arterioles), to the capillaries, to the smallest veins (venules), and on to progressively larger veins. 196. (D) On the AP projection o the elbow, the radial head and ulna normally are somewhat superimposed. T e lateral oblique projection demonstrates the radial head ree o ulnar superimposition. T e lateral projection demonstrates the olecranon process in pro le. T e medial oblique projection demonstrates considerable overlap o the proximal radius and ulna but should clearly demonstrate the

coronoid process ree o superimposition and the olecranon process within the olecranon ossa. 197. (D) Acromioclavicular (AC) joints usually are examined when separation or dislocation is suspected. T ey must be examined in the erect position because in the recumbent position a separation appears to reduce itsel . Both AC joints are examined simultaneously or comparison because separations may be minimal. 198. (D) Myelography is radiologic examination o the structures within the spinal canal. Opaque contrast medium is usually used. Following injection, the contrast medium is distributed to the vertebral region o interest by gravity; the table is angled rendelenburg or visualization o the cervical region and in the Fowler position or visualization o the thoracic and lumbar regions. Although the table is rendelenburg, care must be taken that the patient’s neck is kept in acute extension to compress the cisterna magna and keep contrast medium rom traveling into the ventricles o the brain. 199. (B) Intussusception is the telescoping o one part o the intestinal tract into another. It is a major cause o bowel obstruction in children, usually in the region o the ileocecal valve, and is much less common in adults. Radiographically, intussusception appears as the classic “coil spring,” with barium trapped between olds o the telescoped bowel. T e diagnostic BE procedure occasionally can reduce the intussusception, although care must be taken to avoid per oration o the bowel. Appendicitis occurs when an obstructed appendix becomes in amed. Distension o the appendix occurs, and i the appendix is le untended, gangrene and per oration can result. Regional enteritis (Crohn disease) is a chronic granulomatous in ammatory disorder that can a ect any part o the GI tract but generally involves the area o the terminal ilium. Ulceration and ormation o stulous tracts o en occur. Ulcerative colitis occurs most o en in young adults; its etiology is unknown, although psychogenic or autoimmune actors seem to be involved. 200. (C) T e parietoacanthal projection (Waters’ position) provides an oblique rontal projection o the acial bones. T e maxilla (and antra), zygomatic arches, and orbits are well demonstrated. T e patient is positioned PA with the head resting on the

Answers: 193–208

extended chin so that the OML orms a 37-degree angle with the IR. T e position may be reversed i the patient is positioned AP and the CR is directed 30 degrees cephalad to the IOML. T is position is not pre erred, however, because the acial bones are signi cantly magni ed as a result o increased OID. 201. (B) Inhalation o a oreign substance such as water or ood particles into the airway and/or bronchial tree is called aspiration. Asphyxia is caused by deprivation o oxygen as a result o inter erence with ventilation rom trauma, electric shock, and so on. Atelectasis is incomplete expansion o a lung or portion o a lung. Asystole is cardiac standstill— ailure o the heart muscle to contract and pump blood to vital organs. 202. (B) ERCP may be per ormed to investigate abnormalities o the biliary system or pancreas. T e patient’s throat is treated with a local anesthetic in preparation or the passage o the endoscope. T e hepatopancreatic ampulla (o Vater) is located, and a cannula is passed through it so that contrast medium may be introduced into the common bile duct. Spot images o the common bile duct and pancreatic duct are taken requently in the oblique position. Direct injection o barium mixture into the duodenum occurs during an enteroclysis procedure o the small bowel. 203. (C) A Colles racture usually is caused by a all onto an outstretched (extended) hand to “brake” a all. T e wrist then su ers an impacted transverse racture o the distal inch o the radius with an accompanying chip racture o the ulnar styloid process. Because o the hand position at the time o the all, the racture usually is displaced backward approximately 30 degrees. 204. (C) T e IR or a cross-table (axiolateral or horizontal beam) lateral projection o the hip is placed in a vertical position. T e top edge o the IR should be placed directly above the iliac crest and adjacent to the lateral sur ace o the a ected hip. T e IR is positioned parallel to the emoral neck; the CR is perpendicular to the emoral neck and IR. 205. (A) No hard and ast rule can be applied to restraining pediatric patients. Much depends on the child’s age and emotional temperament and the type o examination. Children never should be

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restrained routinely; many are capable o understanding a clear and simple explanation o why their cooperation is needed. Physical restraint is almost always rightening to the older child, and unnecessary restraint is inexcusable. When a parent or other individual (never a radiation worker!) must be in the radiographic room with the patient, remember to provide proper protection. 206. (B) Radiologic interventional procedures unction to treat pathologic conditions as well as provide diagnostic in ormation. Percutaneous transluminal angioplasty (P A) uses an in atable balloon catheter under uoroscopic guidance to increase the diameter o a plaquestenosed vessel. A stent is a cage-like metal device that can be placed in the vessel to provide support to the vessel wall. A peripherally inserted central catheter (PICC) is also placed under uoroscopic control. It is simply a venous access catheter that can be le in place or several months. It provides convenient venous access or patients requiring requent blood tests, chemotherapy, or large amounts o antibiotics. 207. (C) Hysterosalpingography involves the introduction o a radiopaque contrast medium through a uterine cannula into the uterus and uterine (Fallopian) tubes. T is examination is o en per ormed to document patency o the uterine tubes in cases o in ertility. A retrograde pyelogram requires cystoscopy and involves introduction o contrast medium through the vesicoureteral ori ces and into the renal collecting system. A voiding cystourethrogram also requires cystoscopy and involves lling the bladder with contrast medium and documenting the voiding mechanism. A myelogram is per ormed to investigate the spinal canal. 208. (B) Diagnostic x-ray examinations that require contrast agents include upper gastrointestinal (GI) series, lower GI series (BE), intravenous urogram (IVU), and the occasional gallbladder (GB) series. Patient preparation is somewhat di erent or each o these examinations. An iodinated contrast agent, usually in the orm o several pills, is taken by the patient the evening be ore a scheduled GB examination, and only water is allowed the morning o the examination. T e patient scheduled or an upper GI series must receive NPO (nothing by mouth) a er midnight. A lower GI series (BE) requires that the large bowel be very clean prior to

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the administration o barium; this requires the administration o cathartics (laxatives) and cleansing enemas. Preparation or an IVU requires that the patient be NPO a er midnight; some institutions also require that the large bowel be cleansed o gas and ecal material. A ercare or barium examinations is very important. Patients typically are instructed to take milk o magnesia, increase their intake o ber, drink plenty o water, and expect changes in stool color until all barium is evacuated and to call their physician i they do not have a bowel movement within 24 hours. Because water is removed rom the barium sul ate suspension in the large bowel, it is essential to make patients understand the importance o these instructions to avoid barium impaction in the large bowel. T e use o barium sul ate suspensions is contraindicated when ruling out visceral per oration. 209. (C) Since the heart contracts and relaxes while unctioning to pump blood rom the heart, arteries that are large and those that are in closest proximity to the heart will eel the e ect o the heart’s orce ul contractions in their walls. T e arterial walls pulsate in unison with the heart’s contractions. T is movement may be detected with the ngers in various parts o the body and is re erred to as the pulse. 210. (C) T e AP axial projection ( owne method) o the skull requires that the CR be angled 30 degrees caudad i the OML is perpendicular to the IR (37 degrees caudad i the IOML is perpendicular to the IR). T e rontal and acial bones are projected down and away rom superimposition on the occipital bone. I positioning is accurate, the dorsum sella and posterior clinoid processes will be demonstrated within the oramen magnum. I the CR is angled excessively, the posterior aspect o the arch o C1 will appear in the oramen magnum. 211. (D) T e AP projection will give a general survey and show mediolateral and in erosuperior joint relationships. T e scapular Y position (LAO or RAO) is employed to demonstrate anterior (subcoracoid) or posterior (subacromial) humeral dislocation. T e humerus normally is superimposed on the scapula in this position; any deviation rom this may indicate dislocation. Rotational views must be avoided in cases o suspected racture. T e AP and scapular Y combination is the closest to two views at right angles to each other.

212. (A) T e medial oblique projection requires that the leg be rotated medially until the plantar sur ace o the oot orms a 30-degree angle with the IR. T is position demonstrates the navicular with minimal bony superimposition. T e lateral oblique projection o the oot superimposes much o the navicular on the cuboid. T e navicular is also superimposed on the cuboid in lateral projections. 213. (C) T e obturator oramen is a large oval oramen below each acetabulum and is ormed by the ischium and pubis. T e acetabulum is the bony socket that receives the head o the emur to orm the hip joint. T e upper two- hs o the acetabulum are ormed by the ilium, the lower anterior one- h is ormed by the pubis, and the lower posterior two- hs are ormed by the ischium. T us, the acetabulum is ormed by all three o the bones that orm the pelvis—the ilium, the ischium, and the pubis. 214. (B) Retrograde urography requires ureteral catheterization so that a contrast medium can be introduced directly into the pelvicalyceal system. T is procedure provides excellent opaci cation and structural in ormation but does not demonstrate the unction o these structures. IV studies such as the IVU demonstrate unction. Cystourethrography is an examination o the bladder and urethra, requently per ormed during voiding. Nephrotomography is per ormed a er IV administration o a contrast agent; it may be used to evaluate small intrarenal lesions and renal hypertension. 215. (B) T e AP projection o the coccyx requires the CR to be directed 10 degrees caudally and centered 2 ins superior to the pubic symphysis. T e AP projection o the sacrum requires a 15-degree cephalad angle centered at a point midway between the pubic symphysis and the ASIS. 216. (C) Arthritic changes in the knee result in changes in the joint bony relationships. T ese bony relationships are best evaluated in the AP position. Narrowing o the joint spaces is readily detected more on AP weight-bearing projections than on recumbent projections. 217. (A) T e hypersthenic body type is large and heavy. T e thoracic cavity is short, the lungs are short with broad bases, and the heart is usually in an

Answers: 209–225

almost transverse position. T e diaphragm is high; the stomach and gallbladder are high and transverse. T e large bowel is positioned high and peripheral (and o en requires that 14 × 17 in IRs be placed cross-wise or imaging a BE). 218. (D) When the shoulder is placed in internal rotation, a greater portion o the glenoid ossa is superimposed by the humeral head, and the lesser tubercle is visualized, as in image B. T e external rotation position (image A) removes the humeral head rom a large portion o the glenoid ossa and better demonstrates the greater tubercle. 219. (B) T e AP projection provides a general survey o the abdomen showing the size and shape o the liver, spleen, and kidneys. When per ormed erect, it should demonstrate both hemidiaphragms. T e lateral projection is sometimes requested and is use ul or evaluating the prevertebral space occupied by the aorta. Ventral and dorsal decubitus positions provide a lateral view o the abdomen that is use ul or demonstration o air– uid levels. 220. (C) Diagnostic x-ray examinations that require contrast agents include upper GI series, lower GI series (BE), IVU, and the occasional GB series. Patient preparation is somewhat di erent or each o these examinations. An iodinated contrast agent, usually in the orm o several pills, is taken by the patient the evening be ore a scheduled GB examination, and only water is allowed the morning o the examination. T e patient scheduled or an upper GI series must receive NPO (nothing by mouth) a er midnight. A lower GI series (BE) requires that the large bowel be very clean prior to the administration o barium; this requires the administration o cathartics (laxatives) and cleansing enemas. Preparation or an IVU requires that the patient be NPO a er midnight; some institutions also require that the large bowel be cleansed o gas and ecal material. A ercare or barium examinations is very important. Patients typically are instructed to take milk o magnesia, increase their intake o ber, drink plenty o water, and expect changes in stool color until all barium is evacuated and to call their physician i they do not have a bowel movement within 24 hours. Because water is removed rom the barium sul ate suspension in the large bowel, it is essential to make patients understand the importance o these instructions to avoid barium impaction in the large bowel.

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T e use o barium sul ate suspensions is contraindicated when ruling out visceral per oration. 221. (D) T e patient is supine with the leg(s) abducted (drawn away rom the midline) approximately 40 degrees. T is 40-degree abduction rom the vertical places the long axes o the emoral necks parallel to the IR. T e term adduction re ers to drawing the extremity closer to the midline o the body. 222. (B) Synovial pivot joints are diarthrotic, that is, reely movable. Pivot joints permit rotation motion. Examples include the proximal radioulnar joint that permits supination and pronation o the hand. T e atlantoaxial joint is the articulation between C1 and C2 and permits rotation o the head. T e temporomandibular joint is diarthrotic, having both hinge and planar movements. 223. (C) When the arm is placed in the AP position, the epicondyles are parallel to the plane o the IR, and the shoulder is placed in external rotation. In this position, an AP projection o the humerus, elbow, and orearm can be obtained; it places the greater tubercle o the humerus in pro le. For the lateral projection o the humerus and the internal rotation projection o the shoulder, the arm is internally rotated, elbow somewhat exed, with the back o the hand against the thigh, and the epicondyles are superimposed and perpendicular to the IR. T e lateral projections o the humerus, elbow, and orearm all require that the epicondyles be perpendicular to the plane o the IR. 224. (D) Prior to the start o an IVU, the patient should be instructed to empty the bladder. T is is advised to avoid dilution o the contrast agent. Diluted contrast within the bladder will not a ect the diagnosis o renal abnormalities but may obscure bladder abnormalities. T e patient’s allergy history should be reviewed to avoid the possibility o a severe reaction to the contrast agent. T e patient’s creatinine level and blood urea nitrogen (BUN) should be checked; signi cant elevation o these blood chemistry levels o en suggests renal dys unction. T e normal BUN level is 8 to 25 mg/100 mL; normal creatinine range is 0.6 to 1.5 mg/100 mL. 225. (D) Although routine elbow projections may be essentially negative, conditions may exist (such as an elevated at pad) that seem to indicate the presence o a small racture o the radial head. o demonstrate

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the entire circum erence o the radial head, our exposures are made with the elbow exed 90 degrees and with the humeral epicondyles superimposed and perpendicular to the IR—one with the hand supinated as much as possible, one with the hand lateral, one with the hand pronated, and one with the hand in internal rotation, thumb down. Each maneuver changes the position o the radial head, and a di erent sur ace is presented or inspection. 226. (D) T e radiograph shown is made in the right lateral decubitus position. It is part o a series o radiographs made during an air contrast (double-contrast) BE examination. A double-contrast examination o the large bowel is per ormed to see through the bowel to its posterior wall and to visualize any intraluminal (e.g., polypoid) lesions or masses. Various body positions are used to redistribute the barium and air. o demonstrate the medial and lateral walls o the bowel, decubitus positions are used. T e radiograph shows a right lateral decubitus position because the barium has gravitated to the right side (the side o the hepatic exure). T e air rises and delineates the medial side o the ascending colon and the lateral side o the descending colon. T e posterior wall o the rectum could be visualized using the ventral decubitus position and a horizontal beam lateral to the rectum.

sa e injection site. T e cisterna magna can be used, but the risk o contrast medium entering the ventricles and causing side e ects increases. Diskography requires injection o contrast medium into the individual intervertebral disks. 228. (B) In the lateral position o the skull, the midsagittal plane must be parallel to the IR and the interpupillary line vertical. Flexion o the head is adjusted until the IOML is parallel to the IR. T e CR should enter about 2 in superior to the EAM. T e centering point or a lateral sella turcica is 3⁄4 in anterior and superior to the EAM. 229. (D) Spinal column studies o en are required or evaluation o adolescent scoliosis, thus presenting a two old problem—radiation exposure to youthul gonadal and breast tissues and signi cantly di ering tissue densities/thicknesses. Electronic imaging (CR/DR) helps to reduce the exposure required or the examination. Exposure–dose concerns are also addressed with the use o a compensating lter ( or uni orm density) that incorporates lead shielding or the breasts and gonads (Fig. 2-64).

227. (D) Generally, contrast medium is injected into the subarachnoid space between the third and ourth lumbar vertebrae (Fig. 2-63). Because the spinal cord ends at the level o the rst or second lumbar vertebra, this is considered to be a relatively

End of s pina l cord a t L2 Lumba r puncture ne e dle

S a cra l a ne s the s ia ne e dle

Figure 2-63. Reproduced, with permission, from Waxman: Correlative Neuroanatomy, 24th ed. 2000. McGraw-Hill, Inc. p 75; Fig 6-11.

Figure 2-64. Courtesy of Nuclear Associates.

Answers: 226–237

230. (B) Diarthrodial joints are reely movable joints that distinctively contain a joint capsule. Contrast medium is injected into this joint capsule to demonstrate the menisci, articular cartilage, bursae, and ligaments o the joint under investigation. Synarthrodial joints are immovable joints composed o either cartilage or brous connective tissue. Amphiarthrodial joints allow only slight movement. 231. (B) T e laryngeal prominence, or “Adam’s apple,” is ormed by the thyroid cartilage—the principal cartilage o the larynx. T e thyroid gland, one o the endocrine glands, is lateral and in erior to the thyroid cartilage. T e vocal cords are within the laryngeal cavity. Portions o the pharynx serve as passages or both air and ood. 232. (B) o demonstrate the ankle joint space to best advantage, the plantar sur ace o the oot should be vertical in the AP projection o the ankle. Note that the bula is the more distal o the two long bones o the lower leg and orms the lateral malleolus. T e calcaneus is not well visualized in this projection because o superimposition with other tarsals. 233. (C) Wilm’s tumor is a rapidly developing tumor o the kidney(s). It is the most common childhood renal tumor, usually a ecting only one kidney. Newer treatments are e ective in controlling about 90% o these tumors. As the kidneys are a ected, an IVU would be the most appropriate o the examinations listed. Other use ul examinations would be C scan and sonography. 234. (C) Sacroiliac joints lie obliquely within the pelvis and open anteriorly at an angle o 25 to 30 degrees to the midsagittal plane. A 25- to 30-degree oblique position places the joints perpendicular to the IR. T e right sacroiliac joint may be demonstrated in the LPO and RAO positions with little magni cation variation. 235. (C) Deoxygenated (venous) blood rom the upper body (i.e., head, neck, thorax, and upper extremities) empties into the superior vena cava. Deoxygenated (venous) blood rom the lower body (i.e., abdomen, pelvis, and lower extremities) empties into the in erior vena cava. T e superior and in erior venae cavae empty into the right atrium. T e coronary sinus, which returns venous blood rom the heart, also empties into the right atrium.

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Deoxygenated blood passes rom the right atrium through the tricuspid valve into the right ventricle. From the right ventricle, blood is pumped (during ventricular systole) through the pulmonary semilunar valve into the pulmonary artery—the only artery that carries deoxygenated blood. From the pulmonary artery, blood travels to the lungs, picks up oxygen, and is carried by the our pulmonary veins (the only veins carrying oxygenated blood) to the le atrium. T e oxygenated blood passes through the mitral (or bicuspid) valve during atrial systole and into the le ventricle. During ventricular systole, oxygenated blood rom the le ventricle passes through the aortic semilunar valve into the aorta and into the systemic circulation. 236. (A) Breast tissue is most dense, glandular, and radiographically homogenous in appearance in the postpubertal adolescent. Following pregnancy and lactation, changes occur within the breast that reduce the glandular tissue and replace it with atty tissue (a process called atty in ltration). Menopause causes urther atrophy o glandular tissue. 237. (D) Standard radiographic protocols may be reduced to include two views, at right angles to each other, in emergency and trauma radiography. Department policy and procedure manuals include protocols or radiographic examinations. In the best interest o the patient, and to enable the radiologist to make an accurate diagnosis, standard radiographic protocols should be ollowed. I the radiographer must deviate rom the protocol or believes that additional projections may be help ul, then this should be discussed with the radiologist. Emergency and trauma radiography occasionally is an exception to this rule. I the emergency department physician’s request varies rom the department protocol, the radiographer must respect this. A note should be added to the request so that the radiologist is in ormed o the reason or a change in protocol. For example, a patient who has been involved in a motor vehicle accident may need many radiographic studies, but the emergency department physician may order an AP chest and an AP and cross-table lateral C-spine only. Standard protocol may include a lateral chest and a cone-down view o the atlas and axis, as well as cervical oblique views. T e emergency department physician has made a decision based on experience and expertise that overrules standard protocols. At a later time, when the patient

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has been stabilized, the patient may be sent back to radiology or additional views. 238. (C) T e abdomen can be divided into our quadrants or nine regions. T e liver, gallbladder, and hepatic/right colic exure are all located in the RUQ. T e stomach and spleen are both normally located in the LUQ. 239. (B) About 30 minutes a er the ingestion o atty oods, cholecystokinin is released rom the duodenal mucosa and absorbed into the bloodstream. As a result, the gallbladder is stimulated to contract, releasing bile into the intestine. 240. (C) In the direct PA projection o the wrist, the carpal pisi orm is superimposed on the carpal triquetrum. T e AP oblique projection (medial surace adjacent to the IR) separates the pisi orm and triquetrum and projects the pisi orm as a separate structure. T e pisi orm is the smallest and most palpable carpal. 241. (C) Myelography is used to demonstrate encroachment on and compression o the spinal cord as a result o disk herniation, tumor growth, or posttraumatic swelling o the cord. T is is accomplished by placing positive or negative contrast medium into the subarachnoid space. Myelography will demonstrate posterior protrusion o herniated intervertebral disks or spinal cord tumors. Anterior protrusion o a herniated intervertebral disk does not impinge on the spinal cord and is not demonstrated in myelography. Internal disk lesions can be demonstrated only by injecting contrast medium into the individual disks (diskography). 242. (B) T e radiographer must check blood chemistry levels that are associated with renal unction prior to beginning excretory urography. T ese levels are blood urea nitrogen (BUN) and creatinine. Normal BUN range is 8 to 25 mg/100 mL. Normal creatinine range is 0.6 to 1.5 mg/100 mL. Elevated levels can indicate poor renal unction. 243. (B) A trimalleolar racture involves three separate ractures. T e lateral malleolus is ractured in the “typical” ashion, but the medial malleolus is ractured on both its medial and posterior aspects. T e trimalleolar racture requently is associated with subluxation o the articular sur aces.

244. (C) T e skeleton’s design unctions to protect vital internal organs such as the heart and lungs. Bone stores important minerals (e.g., calcium and phosphorus) and releases them into the blood as needed. Yellow bone marrow is composed mainly o at cells and stores triglycerides or use as an energy reserve. T e endocrine system is associated with hormone production; the integumentary system includes the skin that is important in protection and excretion; the muscular system is responsible or movement and heat production. 245. (C) Major branches o the common carotid arteries (internal carotids) unction to supply the anterior brain, whereas the posterior brain is supplied by the vertebral arteries (branches o the subclavian artery). T e brachiocephalic (innominate) artery is unpaired and is one o the three branches o the aortic arch, rom which the right common carotid artery is derived. T e le common carotid artery comes directly o the aortic arch. 246. (D) Barium sul ate suspension is the usual contrast medium o choice or investigation o the alimentary tract. T ere are, however, a ew exceptions. Whenever there is the possibility o escape o contrast medium into the peritoneal cavity, barium sul ate is contraindicated, and a water-soluble iodinated medium is recommended because it is easily aspirated be ore surgery (or resorbed and excreted by the kidneys). Patients with a ruptured hollow viscus (e.g., per orated ulcer, diverticulitis, etc.), those with suspected large bowel obstruction, and those who are scheduled or surgery are examples o patients who should ingest only water-soluble iodinated media. 247. (C) T ere are many terms (with which the radiographer must be amiliar) that are used to describe radiographic positioning techniques. Cephalad re ers to that which is toward the head, and caudad re ers to that which is toward the eet. Structures close to the source or beginning are said to be proximal, whereas those lying away rom the source or origin are distal. Parts close to the midline are said to be medial, and those away rom the midline are lateral. 248. (C) An oblique projection o the lumbar spine is shown. T is is a 45-degree LPO projection demonstrating the zygapophyseal joints closest to the IR.

Answers: 238–257

T e zygapophyseal joints are ormed by the articulation o the in erior articular acets o one vertebra with the superior articular acets o the vertebra below. Note the “Scotty dog” images that appear in the oblique lumbar spine. Intervertebral oramina are best visualized in the lateral lumbar position. 249. (D) T e chest should be examined in the upright position whenever possible to demonstrate any air– uid levels. For the lateral projection, the patient elevates the arms well enough to avoid upper-arm so -tissue superimposition on the lung elds. In the le lateral position, the right posterior ribs, being remote rom the IR, will be somewhat magni ed and very slightly posterior to the le posterior ribs. T e MSP must remain vertical to avoid “tilt” distortion, and the coronal plane must be vertical to avoid rotation distortion. 250. (B) A cross-sectional image o the abdomen is shown in Figure 2-36. T e large structure on the right, labeled number 1, is the liver. T e gallbladder is seen as a somewhat darker density on the medial border o the liver. T e le kidney is labeled number 4; the right kidney is seen clearly on the other side. T e vertebra is labeled number 5, and the psoas muscles are seen just posterior to the vertebra. Just anterior to the body o the vertebra is the circular aorta, labeled number 3 (some calci cation can be seen as brighter densities). T e somewhat attened in erior vena cava (number 2) is seen to the le o and slightly anterior to the aorta. 251. (A) T e knee (tibio emoral joint) is the largest joint o the body, ormed by the articulation o the emur and tibia. However, it actually consists o three articulations—the patello emoral joint, the lateral tibio emoral joint (lateral emoral condyle with tibial plateau), and the medial tibio emoral joint (medial emoral condyle with tibial plateau). Although the knee is classi ed as a synovial (diarthrotic) hinge-type joint, the patello emoral joint actually is a gliding joint, and the medial and lateral tibio emoral joints are hinge type. 252. (A) Femoral necks are nonpalpable bony landmarks. T e ASIS, pubic symphysis, and greater trochanter are palpable bony landmarks used in radiography o the pelvis and or localization o the emoral necks.

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253. (C) T e ull length o the nasal septum is best demonstrated in the parietoacanthal (Waters’ method) projection. T is is also the single best view or acial bones. T e PA axial (Caldwell method) projection superimposes the petrous structures over the nasal septum, whereas the lateral projection superimposes and obscures good visualization o the septum. T e AP axial projection is used to demonstrate the occipital bone. 254. (C) Placing the patient in a 20- to 30-degree AP rendelenburg position during an upper GI examination helps to demonstrate the presence o a hiatal hernia. A 10- to 15-degree rendelenburg position with the patient rotated slightly to the right also will help demonstrate regurgitation and hiatal hernia. Filling o the duodenal bulb and demonstration o the duodenal loop are best seen in the RAO position. Congenital hypertrophic pyloric stenosis is caused by excessive thickening o the pyloric sphincter. It is noted in in ancy and characterized by projectile vomiting. T e pyloric valve will let very little pass through, and as a result, the stomach becomes enlarged (hypertrophied). 255–256. (255, B; 256, D) T e image illustrates a PA projection o the wrist. T is projection best demonstrates visualization o the distal radioulnar joint, the proximal and distal rows o carpals, and the proximal metacarpals (more o the metacarpals should be seen here). T e base o the h metacarpal is number 4. T e trapezium (lateral carpal, distal row) is number 1; the base o the rst metacarpal is seen articulating with the trapezium orming the (saddle) carpometacarpal articulation. Number 2 is the scaphoid—the most lateral carpal o the proximal carpal row. Number 3 is the radial styloid process. Number 5 is the pisi orm, seen just lateral to, and partially superimposed upon, the triquetrum. Number 6 is the ulnar styloid process. 257. (D) T e anterior oblique positions (LAO and RAO) o the cervical spine require a 15-degree caudal angulation and demonstrate the intervertebral oramina closest to the IR. T e posterior oblique positions (LPO and RPO) require that the CR be directed 15 degrees to C4. T e posterior oblique positions demonstrate the intervertebral oramina arther away rom the IR.

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258. (C) T e degree o anterior and posterior motion occasionally is diminished with a whiplash type o injury. Anterior ( orward, exion) and posterior (backward, extension) motion is evaluated in the lateral position, with the patient assuming the best possible exion and extension. Le - and right-bending images o the thoracic and lumbar vertebrae are obtained requently when evaluating scoliosis. 259. (A) When one cheekbone is depressed, a tangential projection is required to “open up” the zygomatic arch and draw it away rom the overlying cranial bones. T is is accomplished by placing the patient in the SMV position, rotating the head 15 degrees toward the a ected side, and centering to the zygomatic arch. A 30-degree rotation places the mandibular shadow over the zygomatic arch. 260. (D) Normal blood pressure is 110 to 140 mm Hg systolic and 60 to 80 mm Hg diastolic. High blood pressure (hypertension) is indicated by systolic pressure higher than 140 mmHg and diastolic pressure higher than 90 mm Hg. Hypertension can be identi ed as extreme or moderate. Extreme hypertension can result in brain damage within just a ew minutes. Moderate hypertension can cause damage to organs: the lungs, kidneys, brain, heart, and so on. Various disease processes can produce hypertension as well as contributing actors such as medications, obesity, smoking, and stress. 261. (A) Accurate positioning o the skull requires the use o several baselines. In the gure, line 1 represents the glabellomeatal line (GML), line 2 is the orbitomeatal line (OML), line 3 is the in raorbitomeatal line (IOML), and line 4 is the acanthomeatal line (AML). T e OML and the IOML usually are separated by 7 degrees. T e OML and the GML usually are separated by 8 degrees (thereore, there is a 15-degree di erence between the GML and the IOML). It is use ul to remember these di erences because CR angulation must be adjusted when using a baseline other than the one recommended or a particular position. For example, i it is recommended that the CR be angled 30 degrees to the OML, then the CR would be angled 37 degrees to the IOML. 262. (D) T e SMV projection o the skull requires that the patient’s neck be extended, placing the vertex

adjacent to the IR holder/upright Bucky so that the IOML is parallel with the IR. T is projection is useul or demonstrating the ethmoidal and sphenoidal sinuses, pars petrosae, mandible, and oramina ovale and spinosum. T e lateral projection o the skull requires that the patient be in the prone oblique position with the MSP parallel to the IR and the interpupillary line perpendicular to the IR. T is position also requires that the IOML (line 3) be parallel to the long axis o the IR. T e AP and PA axial projections o the skull require the OML or IOML to be perpendicular to the IR. 263. (B) Orthoroentgenography is the radiographic measurement o long-bone length. It can be required on adults or children having extremity length (especially leg) discrepancies. T is can be per ormed most easily with the use o the metallic Bell-T ompson scale secured to the x-ray tabletop adjacent to the limb being examined (or between both limbs or simultaneous bilateral examination). A 14 × 17 in IR is in the Bucky tray (to permit movement o the IR between exposures), and three well-collimated exposures are made—at the hip joint, the knee joint, and the ankle joint. A cannula is a tube placed in a cavity to introduce or withdraw material and is unrelated to orthoroentgenography. 264. (C) Intervertebral joints (occupied by the intervertebral disks) are well visualized in the lateral projection o all the vertebral groups. Cervical articular acets ( orming zygapophyseal/interarticular joints) are 90 degrees to the midsagittal plane and, thereore, are well demonstrated in the lateral projection. T e cervical intervertebral oramina lie 45 degree to the midsagittal plane (and 15–20 degrees to a transverse plane) and, there ore, are demonstrated in the oblique position. 265. (C) T e patient is placed in a true lateral position, and the CR is directed perpendicular to a point 1/2 in distal to the nasion. An 8 × 10 in IR divided in hal may be used or this procedure. 266. (B) o reduce anxiety prior to the examination, the radiographer should give the patient a ull explanation o the enema procedure. T is explanation should include keeping the anal sphincter tightly contracted, relaxing the abdominal muscles, and deep breathing. T e barium suspension should be either just below body temperature

Answers: 258–273

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(at 85–90°F) to prevent injury and bowel irritation or cold (at 41°F) to produce less colonic irritation and to stimulate contraction o the anal sphincter. 267. (D) X-ray arthrography requires the use o local anesthesia; sterile technique must be observed to avoid introducing in ection into the joint. Fluoroscopy is used or proper placement o the needle and to obtain images immediately a er the introduction o contrast medium. Many physicians ollow up the x-ray arthrogram with a magnetic resonance (MR) arthrogram to visualize additional so tissue structures. Arthrography is per ormed to detect compromised knee capsule structures, meniscal damage, ligament tears, and Baker cysts. 268. (B) Blowout ractures o the orbital oor are caused by a direct blow to the eye. T e orbital oor is caused to collapse; this carries the in erior rectus muscle through the racture site and into the maxillary sinus. Diplopia (double vision) o en results. Blowout ractures are well demonstrated with the Waters’ method (parietoacanthal projection) and by using tomographic studies. A parietoacanthal projection with the OML perpendicular and the CR angled 30 degrees caudad also will demonstrate the orbital oor in pro le. T e zygoma usually is not involved with a blowout racture but rather with a tripod racture. 269. (D) T e phase o respiration is exceedingly important in thoracic radiography because lung expansion and the position o the diaphragm strongly in uence the appearance o the nished radiograph. Inspiration and expiration radiographs o the chest are taken to demonstrate air in the pleural cavity (pneumothorax), to demonstrate atelectasis (partial or complete collapse o one or more pulmonary lobes) or the degree o diaphragm excursion, or to detect the presence o a oreign body. T e expiration image will require a somewhat greater exposure (6–8 kV more) to compensate or the diminished quantity o air in the lungs. 270. (C) Shoulder arthrograms (Fig. 2-65) are used to evaluate rotator cu tear, glenoid labrum (a ring o brocartilaginous tissue around the glenoid ossa), and rozen shoulder. Routine radiographs demonstrate arthritis, and the addition o a transthoracic humerus or scapular Y projection would be used to demonstrate luxation (dislocation).

Figure 2-65. Courtesy of Stamford Hospital, Department of Radiology.

271. (D) In the AP projection o the elbow, the proximal radius and ulna are partially superimposed. In the lateral projection, the radial head is partially superimposed on the coronoid process, acing anteriorly. In the medial oblique projection, there is even greater superimposition. T e lateral oblique projection completely separates the proximal radius and ulna, projecting the radial head, neck, and tuberosity ree o superimposition with the proximal ulna. 272. (B) Changes in hormone levels a ect changes in the glandular tissue o the breast. T ese breast tissue changes are seen during breast development, during pregnancy and lactation, and during menopause. Women at higher risk o developing breast cancer include those having experienced early menses (be ore age 12 years), late menopause (a er age 52 years), and nulliparity (no ull- or late-term pregnancies). Risks other than hormonal include amily and personal history and age. T e greatest single risk actor or breast cancer is gender—being emale. Although occurrence o breast cancer in men is not unknown, it is airly rare. 273. (B) T ere are several sur ace landmarks and localization points that can help the radiographer in positioning various body structures. T e jugular notch, located at the superior aspect o the manubrium, is approximately opposite the 2–3 interspace. T e sternal angle is located opposite the 4–5 interspace. T e xiphoid (or ensi orm) process is located opposite 10.

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274. (D) With the patient in the AP position, the scapula and upper thorax are normally superimposed. With the arm abducted, the elbow exed, and the hand supinated, much o the scapula is drawn away rom the ribs. T e patient should not be rotated toward the a ected side because this causes superimposition o ribs on the scapula. T e exposure is made during quiet breathing to obliterate pulmonary vascular markings.

279. (A) Because sinus examinations are per ormed to evaluate the presence or absence o uid, they must be per ormed in the erect position with a horizontal x-ray beam. T e PA axial (Caldwell) projection demonstrates the rontal and ethmoidal sinus groups, and the parietoacanthal projection (Waters’ method) shows the maxillary sinuses. T e lateral position demonstrates all the sinus groups, and the SMV position is used requently to demonstrate the sphenoidal sinuses.

275. (D) T e two innominate bones (os coxae) make up the pelvis. Each innominate bone is made three bones: ilium, ischium, and pubis. T ese three bones contribute to orm the ormation o the acetabulum. When the interior o the acetabulum is viewed, the ilium comprises its upper two-thirds, the ischium comprises its lower posterior twothirds, and the pubis comprises the lower anterior one-third o the acetabulum.

280. (A) T e plantodorsal projection o the os calsis/ calcaneus is described. It is per ormed supine and requires cephalad angulation. T e CR enters the plantar sur ace and exits the dorsal sur ace. T e axial dorsoplantar projection requires that the CR enter the dorsal sur ace o the oot and exit the plantar sur ace.

276. (A) Sternoclavicular joints should be imaged in the PA position whenever possible to keep the object-to-image-receptor distance (OID) to a minimum. T e oblique position (about 15 degrees) opens the joint closest to the IR. T e erect position may be used but is not required. Weight-bearing images are not recommended or sternoclavicular joints because they o en are or acromioclavicular joints.

281. (D) o clearly demonstrate the atlas and axis without superimposition o the teeth or the base o the skull, a line between the maxillary occlusal plane (edge o upper teeth) and mastoid tip must be vertical. I the head is exed too much, the teeth will be superimposed. I the head is extended too much, the cranial base will be superimposed on the area o interest. A line between the mentum and the mastoid tip is used to demonstrate the odontoid process only through the oramen magnum (Fuchs method).

277. (D) T is is a modi cation o the parietoacanthal projection (Waters’ method) in which the patient is requested to open the mouth, and then the skull is positioned so that the OML orms a 37-degree angle with the IR. T e CR is directed through the sphenoidal sinuses and exits the open mouth. T e routine parietoacanthal projection (with mouth closed) is used to demonstrate the maxillary sinuses projected above the petrous pyramids. T e rontal and ethmoidal sinuses are best visualized in the PA axial position (modi ed Caldwell method). 278. (C) T e ribs below the diaphragm are best demonstrated with the diaphragm elevated. T is is accomplished by placing the patient in a recumbent position and by taking the exposure at the end o exhalation. Conversely, the ribs above the diaphragm are best demonstrated with the diaphragm depressed. Placing the patient in the erect position and taking the exposure at the end o deep inspiration accomplishes this.

282. (A) With a patient in the PA position and the OML perpendicular to the table, a 15- to 20-degree caudal angulation would place the petrous ridges in the lower third o the orbit. o achieve the same result in a baby or a small child, it is necessary or the radiographer to decrease the angulation or modi y the angulation to 10 to 15 degrees caudal. T e reason or this can be understood by examining the baselines or skull positioning. In the adult skull, the OML and IOML are about 7 degrees apart. In a baby or small child, the di erence is larger, about 15 degrees apart. Remember that in adults, the head makes up about one-seventh the length o the body. In children, the head is about one- ourth the length o the body. T ese di erences must be considered in radiographic examination o the skull or babies. 283–284. (283, B; 284, D) T e gure illustrates the aortic arch (number 1) and its three main branches— the brachiocephalic artery (number 6), the le

Answers: 274–291

common carotid artery (number 4), and the le subclavian artery (number 2). T e right common carotid artery (number 5) and the right subclavian artery (number 7) are branches o the brachiocephalic. T e vertebral arteries are the rst main branch o the subclavian arteries. T e le vertebral artery is labeled number 3. 285. (B) When the oot is positioned or a lateral projection, the plantar sur ace should be perpendicular to the IR so as to superimpose the metatarsals. T is may be accomplished with the patient lying on either the a ected or the una ected side (usually the a ected), that is, mediolateral or lateromedial. T e talo bular articulation is best demonstrated in the medial oblique projection o the ankle. 286. (B) T e parietoacanthial (Waters’ method) projection demonstrates the maxillary sinuses. T e modied Waters’ position, with the CR directed through the open mouth, will demonstrate the sphenoid sinuses through the open mouth. T e PA axial projection demonstrates the rontal and ethmoidal sinus groups. T e lateral projection, with the CR entering 1 in posterior to the outer canthus, demonstrates all the paranasal sinuses. X-ray examinations o the sinuses always should be per ormed erect to demonstrate leveling o any uid present. 287. (C) T e typical vertebra, shown in Figure 2-66, is divided into two portions—the body (anteriorly) and the vertebral arch (posteriorly). T e vertebral arch supports seven processes—two transverse, one spinous (number 3), two superior articular (number 4), and two in erior articular (number 2).

4 5

3

1 2

Figure 2-66.

6

119

T e superior articular processes and the superjacent in erior articular processes join to orm zygapophyseal joints. Pedicles (number 5) project posteriorly rom the vertebral body (number 6). T eir upper and lower sur aces orm vertebral notches. Superjacent vertebral notches orm intervertebral oramina. T e lamina is represented by number 1. T e transverse and spinous processes serve as attachments or muscles or articulations or ribs in the thoracic region. T e superior and in erior sur aces o the vertebral body are covered with articular cartilage, and between the vertebral bodies lie the intervertebral disks. 288. (A) T e straight PA projection (0 degrees), with CR directed perpendicular to the IR, e ectively demonstrates the mandibular body. In this position, the rami and condyles are superimposed on the occipital bone and petrous portion o the temporal bone. o better visualize the rami and condyles, the CR is directed cephalad 20 to 30 degrees. 289. (D) A uoroscopic unit with spot device and tilt table should be used or endoscopic retrograde pancreatography. T e rendelenburg position is sometimes necessary to ll the interhepatic ducts, and a semierect position may be necessary to ll the lower end o the common bile duct. Also necessary are a beroptic endoscope or locating the hepatopancreatic ampulla and polyethylene catheters or the introduction o contrast medium. 290. (B) Intussusception is a type mechanical obstruction involving “telescoping” o a portion the pediatric large intestine, causing obstruction. Volvulus is a condition o the pediatric intestine involving twisting o intestinal loops, causing obstruction. T ese are described as mechanical conditions. Paralytic (adynamic) ileus is a type o obstruction caused as a result loss o intestinal motility/contraction. 291. (C) T e diaphragm is the major muscle o respiration. On inspiration/inhalation, the diaphragm and abdominal viscera are depressed, enabling the lling and expansion o the lungs, accompanied by upward movement o the sternum and ribs. During expiration/exhalation, air leaves the lungs and they de ate, and the diaphragm relaxes and moves to a more superior position along with the abdominal viscera. As the diaphragm relaxes and moves up, the sternum and ribs move in eriorly.

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2: Imaging Procedures

292. (B) T e axial trauma lateral (Coyle) position is described. I routine elbow projections in extension are not possible because o limited part movement, this position can be used to demonstrate the coronoid process and/or radial head. With the elbow exed 90 degrees and the CR directed to the elbow joint at an angle o 45 degrees medially (i.e., toward the shoulder), the joint space between the radial head and capitulum should be revealed. With the elbow exed 80 degrees and the CR directed to the elbow joint at an angle o 45 degrees laterally (i.e., rom the shoulder toward the elbow), the elongated coronoid process will be visualized. 293. (C) T e oot is composed o the 7 tarsal bones, 5 metatarsals, and 14 phalanges. T e metatarsals and phalanges are miniature long bones; each has a sha , base (proximal), and head (distal). T e bases o the rst to third metatarsals articulate with the three cunei orms. T e bases o the ourth and h metatarsals articulate with the cuboid. T e heads o the metatarsals articulate with the bases o the rst row o phalanges. 294. (C) T e posterior oblique positions (LPO and RPO) o the lumbar vertebrae demonstrate the zygapophyseal joints closer to the IR. T e le zygapophyseal joints are demonstrated in the LPO position, whereas the right zygapophyseal joints are demonstrated in the RPO position. T e lateral position is use ul to demonstrate the intervertebral disk spaces, intervertebral oramina, and spinous processes. 295–297. (295, B; 296, B; 297, C) An AP, external rotation, projection o the shoulder is pictured. T e hand is supinated, and the arm is in the anatomical position. T ere ore, the greater tubercle (number 3) is well visualized. T e greater portion o the clavicle is seen, the acromioclavicular joint (number 1), the acromion process (number 2), the coracoid process

(number 4), and the glenohumeral joint (number 5). T e coronoid process is located on the ulna. 298. (A) T e sacroiliac joints angle posteriorly and medially 25 degrees to the MSP. T ere ore, to demonstrate the sacroiliac joints with the patient in the AP position, the a ected side must be elevated 25 degrees. T is places the joint space perpendicular to the IR and parallel to the CR. T ere ore, the RPO position will demonstrate the le sacroiliac joint, and the LPO position will demonstrate the right sacroiliac joint. When the examination is perormed with the patient in the PA position, the una ected side will be elevated 25 degrees. 299. (D) Since the kidneys do not lie parallel to the IR in the AP position, the oblique positions are used during IVU to visualize them better. With the AP oblique projections (RPO and LPO positions), the kidney that is arther away is placed parallel to the IR, and the kidney that is closer is placed perpendicular to the IR. T ere ore, in the LPO position, the le kidney, being closer, is perpendicular to the IR. T e right kidney, the one arther away, is placed parallel to the IR. 300. (C) AP and lateral projections o the airway and larynx are required occasionally to rule out oreign body, polyps, tumors, or any other condition suspected o causing some airway obstruction. T e AP projection is positioned as or an AP cervical spine projection with the CR perpendicular to the laryngeal prominence. T e lateral projection is positioned as or a lateral cervical spine projection and is centered to the coronal plane passing through the trachea (anterior to the cervical spine) at the level o the laryngeal prominence. Centering just below the EAM would demonstrate the nasopharynx. Centering at the mandibular angles would demonstrate the oropharynx. Exposures are made on slow inspiration to visualize air- lled structures.

Subspecialty List

QUESTION NUMBER AND SUBSPECIALTY correspond to subcategories in each o the f ve ARRT examination specif cation sections 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30.

General procedural considerations Extremities Extremities Extremities Spine and pelvis Abdomen and GI studies General procedural considerations T orax Head T orax T orax T orax Abdomen and GI studies Urological studies Abdomen and GI studies Extremities Extremities Abdomen and GI studies General procedural considerations Head Spine and pelvis T orax T orax Spine and pelvis Extremities T orax General procedural considerations Head Head Extremities

31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65.

T orax Extremities Abdomen and the GI studies Abdomen and GI studies T orax Extremities Extremities Extremities Spine and pelvis Other Spine and pelvis Head Extremities Abdomen and GI studies Abdomen and GI studies T orax Extremities T orax T orax Extremities General procedural considerations T orax Abdomen and G.I. studies Extremities Extremities Extremities Extremities T orax General procedural considerations Spine and pelvis Extremities Extremities Extremities T orax Extremities

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122

66. 67. 68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 78. 79. 80. 81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92. 93. 94. 95. 96. 97. 98. 99. 100. 101. 102. 103. 104. 105. 106. 107. 108. 109. 110. 111. 112. 113. 114. 115. 116.

2: Imaging Procedures

Extremities Extremities General procedural considerations Other Head Extremities Extremities Spine and pelvis Extremities Extremities Extremities Extremities T orax T orax T orax T orax Extremities General procedural considerations Spine and pelvis Spine and pelvis Head Head Other Extremities Extremities Spine and pelvis Head Extremities Extremities Spine and pelvis T orax Extremities Head Abdomen and the GI studies Extremities T orax Urological studies Extremities Abdomen and GI studies Extremities Extremities Abdomen and GI studies Abdomen and GI studies Extremities Extremities Extremities Extremities Head Extremities Extremities Extremities

117. 118. 119. 120. 121. 122. 123. 124. 125. 126. 127. 128. 129. 130. 131. 132. 133. 134. 135. 136. 137. 138. 139. 140. 141. 142. 143. 144. 145. 146. 147. 148. 149. 150. 151. 152. 153. 154. 155. 156. 157. 158. 159. 160. 161. 162. 163. 164. 165. 166. 167.

Spine and pelvis General procedural considerations Spine and pelvis Spine and pelvis Spine and pelvis Abdomen and GI studies Extremities T orax Spine and pelvis General procedural considerations Spine and pelvis Extremities Extremities Spine and pelvis T orax Head Urological studies General procedural considerations Extremities Spine and pelvis Abdomen and GI studies General procedural considerations Extremities Extremities Spine and pelvis General procedural considerations General procedural considerations Head Abdomen and GI studies Spine and pelvis Extremities Extremities Abdomen and G.I. studies Abdomen and G.I. studies Extremities General procedural considerations General procedural considerations Head Extremities Extremities Extremities T orax Extremities Extremities Extremities Abdomen and GI studies Abdomen and GI studies Extremities T orax T orax Extremities

Subspecialty List

168. 169. 170. 171. 172. 173. 174. 175. 176. 177. 178. 179. 180. 181. 182. 183. 184. 185. 186. 187. 188. 189. 190. 191. 192. 193. 194. 195. 196. 197. 198. 199. 200. 201. 202. 203. 204. 205. 206. 207. 208. 209. 210. 211. 212. 213. 214. 215. 216. 217. 218.

Extremities Head Head Abdomen and GI studies General procedural considerations Abdomen and GI studies Spine and pelvis T orax T orax T orax Extremities Spine and pelvis Extremities Head T orax Abdomen and GI studies Abdomen and GI studies Abdomen and GI studies Extremities Spine and pelvis Extremities Spine and pelvis Spine and pelvis Urological studies Extremities Extremities Abdomen and GI studies General procedural considerations Extremities Extremities Other Abdomen and GI studies Head T orax Abdomen and GI studies Extremities Spine and pelvis General procedural considerations Other Other Abdomen and GI studies General procedural considerations Head Extremities Extremities Spine and pelvis Urological procedures Spine and pelvis Extremities General procedural considerations Extremities

219. 220. 221. 222. 223. 224. 225. 226. 227. 228. 229. 230. 231. 232. 233. 234. 235. 236. 237. 238. 239. 240. 241. 242. 243. 244. 245. 246. 247. 248. 249. 250. 251. 252. 253. 254. 255. 256. 257. 258. 259. 260. 261. 262. 263. 264. 265. 266. 267. 268. 269.

Abdomen and GI studies Abdomen and the GI studies Spine and pelvis Spine and pelvis Extremities Urological studies Extremities Abdomen and GI studies Other Head Spine and pelvis Other T orax Extremities Urological studies Spine and pelvis T orax Other General procedural considerations Abdomen and GI studies Abdomen and GI studies Extremities Other Urological studies Extremities General procedural considerations Head Abdomen and GI studies General procedural considerations Spine and pelvis T orax Abdomen and GI studies Extremities Spine and pelvis Head Abdomen and GI studies Extremities Extremities Spine and pelvis Spine and pelvis Head General procedural considerations Head Head Extremities Spine and pelvis Head Abdomen and GI studies Other Head T orax

123

124

270. 271. 272. 273. 274. 275. 276. 277. 278. 279. 280. 281. 282. 283. 284. 285.

2: Imaging Procedures

Other Extremities Other Spine and pelvis T orax Spine and pelvis Extremities Head T orax Head Extremities Spine and pelvis Head T orax T orax Extremities

Targeted Reading Bontrager KL, Lampignano JP. extbook o Radiographic Positioning and Related Anatomy. 8th ed. St Louis, MO: Mosby; 2014. Frank ED, Long BW, Smith BJ. Merrill’s Atlas o Radiographic Positioning and Procedures.Vols 1, 2, and 3. 12th ed. St. Louis, MO: Mosby; 2012.

286. 287. 288. 289. 290. 291. 292. 293. 294. 295. 296. 297. 298. 299. 300.

Head Spine and pelvis Head Abdomen and GI studies Abdomen and GI studies T orax Extremities Extremities Spine and pelvis Extremities Extremities Extremities Spine and pelvis Urological studies T orax

Saladin KS. Anatomy and Physiology: T e Unity o Form and Function. 7th ed. New York, NY: McGraw-Hill; 2015. ortora GJ, Derrickson B. Principles o Anatomy and Physiology. 12th ed. Hoboken, NJ: John Wiley & Sons, Inc; 2009. Saia DA. Radiography PREP. 8th ed. New York, NY: McGraw-Hill; 2015.

CHAPTER 3

Radiation Protection Questions

DIRECTIONS (Questions 1 through 200): Each of the numbered items or incomplete statements in this section is followed by answers or by completions of the statement. Select the one lettered answer or completion that is best in each case. 1. Biologic material irradiated under hypoxic conditions is (A) more sensitive than when irradiated under oxygenated conditions (B) less sensitive than when irradiated under anoxic conditions (C) less sensitive than when irradiated under oxygenated conditions (D) una ected by the presence or absence o oxygen 2. According to the National Council on Radiation Protection and Measurements (NCRP), the monthly gestational dose-equivalent limit or embryo/ etus o a pregnant radiographer is (A) (B) (C) (D)

0.1 mSv 0.5 mSv 1.0 mSv 5.0 mSv

4. Stochastic/probabilistic e ects o radiation are those that 1. have a threshold 2. may be described as “all-or-nothing” e ects 3. are late e ects (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

5. What percentage o public exposure to ionizing radiation is rom medical sources? (A) (B) (C) (D)

5% 10% 25% 50%

6. Which o the ollowing cell types has the greatest radiosensitivity in the adult human? (A) (B) (C) (D)

Nerve cells Muscle cells Spermatids Lymphocytes

3. A time o 1.5 minutes is required or a particular uoroscopic examination, whose exposure rate is 275 mR/h. What is the approximate radiation exposure or the radiologic sta present in the uoroscopy room during the examination? (A) (B) (C) (D)

183 mR 68.7 mR 18.33 mR 6.87 mR 125

126

3: Radiation Protection

7. Guidelines or the use o protective shielding state that gonadal shielding should be used 1. i the patient has reasonable reproductive potential 2. when the gonads are within 5 cm o the collimated eld 3. when tight collimation is not possible (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 2 and 3 only

8. T e interaction between ionizing radiation and the target molecule that is most likely to occur is the (A) (B) (C) (D)

direct e ect indirect e ect target e ect random e ect

9. Sources o natural background radiation include 1. radon 2. internal sources 3. thoron (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

10. T e unit used to express kinetic energy released in matter is the (A) (B) (C) (D)

erg gray kerma rad

11. Which acute radiation syndrome requires the largest exposure be ore the associated e ects become apparent? (A) (B) (C) (D)

Hematopoietic Gastrointestinal Central nervous system (CNS) Skeletal

12. What is the established annual occupational dose-equivalent limit or the lens o the eye? (A) (B) (C) (D)

250 mSv 150 mSv 50 mSv 10 mSv

13. Occupational radiation monitoring is required when it is possible that the individual might receive more than (A) (B) (C) (D)

5 mrem 10 mrem one-tenth the annual dose limit one- ourth the annual dose limit

14. Sources o natural background radiation contributing to whole-body radiation dose include 1. dental x-rays 2. terrestrial radionuclides 3. internal radionuclides (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

15. Irradiation o water molecules within the body and their resulting breakdown is termed (A) (B) (C) (D)

epilation radiolysis proli eration repopulation

16. Diagnostic x-radiation may be correctly described as (A) (B) (C) (D)

low energy, low LE low energy, high LE high energy, low LE high energy, high LE

Questions: 7–25

17. Which o the ollowing is (are) used to account or the di erences in tissue characteristics when determining e ective dose to biologic material? 1. issue weighting actors (Wt) 2. Radiation weighting actors (Wr) 3. Absorbed dose (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

18. T e x-ray interaction with matter that is responsible or the majority o scattered radiation reaching the image receptor (IR) is (A) (B) (C) (D)

the photoelectric e ect Compton scatter classical scatter T ompson scatter

19. T e exposure rate to a body 4 rom a source o radiation is 16 R/h. What distance rom the source would be necessary to decrease the exposure to 6 R/h? (A) (B) (C) (D)

5 7 10 14

20. Protective devices such as lead aprons unction to protect the user rom 1. scattered radiation 2. the primary beam 3. remnant radiation (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

127

21. Late radiation-induced somatic e ects include 1. thyroid cancers 2. cataractogenesis 3. genetic mutations (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

22. Each time an x-ray beam scatters, its intensity at 1 m rom the scattering object is what raction o its original intensity? (A) (B) (C) (D)

1/10 1/100 1/500 1/1,000

23. T e law o Bergonié and ribondeau states that cells are more radiosensitive i they are 1. highly proli erative 2. highly di erentiated 3. immature (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

24. A thermoluminescent dosimetry system would use which o the ollowing crystals? (A) (B) (C) (D)

Silver halide Sodium thiosul ate Lithium uoride Aluminum oxide

25. Sources o secondary radiation include 1. background radiation 2. leakage radiation 3. scattered radiation (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

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3: Radiation Protection

26. All the ollowing have an e ect on patient dose except (A) (B) (C) (D)

kilovoltage milliampere-seconds ocal spot size inherent ltration

27. T e photoelectric e ect is more likely to occur with 1. absorbers having a high Z number 2. high-energy incident photons 3. positive contrast media (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

28. An increase in total ltration o the x-ray beam will increase (A) (B) (C) (D)

patient skin dose beam HVL image contrast milliroentgen (mR) output

29. In radiation protection, the product o absorbed dose, tissue weighting actor, and radiation weighting actor is used to determine (A) (B) (C) (D)

C/kg mR ED QF

30. Which o the ollowing is recommended or the pregnant radiographer? (A) Change dosimeters weekly. (B) Wear a second dosimeter under the lead apron. (C) Wear two dosimeters and switch their positions appropriately. (D) T e pregnant radiographer must leave radiation areas or duration o the pregnancy.

31. T e annual dose limit or medical imaging personnel includes radiation rom 1. occupational exposure 2. background radiation 3. medical x-rays (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

32. Which o the ollowing anomalies is (are) possible i an exposure dose o 40 rad (400 mGy) were delivered to a pregnant uterus in the third week o pregnancy? 1. Skeletal anomaly 2. Organ anomaly 3. Neurologic anomaly (A) (B) (C) (D)

1 only 2 only 2 and 3 only 1, 2, and 3

33. I a quantity o ionizing radiation is delivered to a body over a long period o time, the e ect (A) will be greater than i it were delivered all at one time (B) will be less than i it were delivered all at one time (C) has no relation to how it is delivered in time (D) depends solely on the radiation quality 34. Moving the image intensi er closer to the patient during uoroscopy 1. decreases patient dose 2. improves image quality 3. decreases the SID (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

Questions: 26–44

35. Which o the ollowing is (are) composed o nondividing, di erentiated cells? 1. Neurons and neuroglia 2. Epithelial tissue 3. Lymphocytes (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

40. What is the term used to describe x-ray photon interaction with matter and the trans erence o part o the photon’s energy to matter? (A) (B) (C) (D)

37. What is the minimum lead requirement or lead aprons, according to the NCRP? (A) (B) (C) (D)

1.0 mm Pb equivalent 0.25 mm Pb equivalent 0.50 mm Pb equivalent 0.05 mm Pb equivalent

38. T e most radiosensitive portion o the GI tract is the (A) (B) (C) (D)

upper esophagus stomach small bowel cecum and ascending colon

39. Immature cells are re erred to as 1. undi erentiated cells 2. stem cells 3. genetic cells (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

Absorption Scattering Attenuation Divergence

41. Advantages o anatomic compression during imaging include

36. How does ltration a ect the primary beam? (A) It increases the average energy o the primary beam. (B) It decreases the average energy o the primary beam. (C) It makes the primary beam more penetrating. (D) It increases the intensity o the primary beam.

129

1. Decreased patient dose 2. Improved contrast resolution 3. Improved spatial resolution (A) (B) (C) (D) 42.

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

o be in compliance with radiation sa ety standards, the uoroscopy exposure switch must (A) (B) (C) (D)

sound during uoro-on time be on a 6- -long cord terminate uoro a er 5 minutes be the “dead man” type

43. Any wall that the use ul x-ray beam can be directed toward is called a (A) (B) (C) (D)

secondary barrier primary barrier leakage barrier scattered barrier

44. T e annual dose limit or occupationally exposed individuals is valid or (A) (B) (C) (D)

alpha, beta, and x-radiations x- and gamma radiations only beta, x-, and gamma radiations all ionizing radiations

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3: Radiation Protection

45. T e interaction between x-ray photons and matter shown in Figure 3-1 is associated with

49. LE is best de ned as

1. an inner shell electron 2. photoelectric e ect 3. partial energy trans er rom photon to electron

1. a method o expressing radiation quality 2. a measure o the rate at which radiation energy is trans erred to so tissue 3. absorption o polyenergetic radiation

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 2 and 3 only Eje cte d K s he ll e le ctron

Incide nt photon

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

50. For exposure to 1 rad o each o the ollowing ionizing radiations, which would result in the greatest dose to the individual? (A) (B) (C) (D)

External source o External source o Internal source o External source o

1-MeV x-rays diagnostic x-rays alpha particles beta particles

51. T e skin response to radiation exposure that appears as hair loss is known as Figure 3-1.

46. Patient dose increases as uoroscopic (A) (B) (C) (D) 47.

FOV increases FOV decreases FSS increases FSS decreases

ypes o gonadal shielding include which o the ollowing? 1. Flat contact 2. Shaped contact (contour) 3. Shadow (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

48. What unit o measure is used to express ionizing radiation dose to biologic material? (A) (B) (C) (D)

Roentgen (C/kg) Rad (Gy) Rem (Sv) RBE

(A) (B) (C) (D)

dry desquamation moist desquamation erythema epilation

52. Examples o late e ects o ionizing radiation on humans include 1. leukemia 2. local tissue damage 3. malignant disease (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

53. T e reduction in the intensity o an x-ray beam as it passes through material is termed (A) (B) (C) (D)

absorption scattering attenuation divergence

Questions: 45–63

54. Which type o dose–response relationship represents radiation-induced leukemia and genetic e ects? (A) (B) (C) (D)

Linear, threshold Nonlinear, threshold Linear, nonthreshold Nonlinear, nonthreshold

55. A dose o 25 rad to the etus during the seventh or eighth week o pregnancy is likely to cause which o the ollowing? (A) (B) (C) (D)

Spontaneous abortion Skeletal anomalies Neurologic anomalies Organogenesis

131

59. T e largest amount o diagnostic x-ray absorption is most likely to occur in which o the ollowing tissues? (A) (B) (C) (D)

Lung Adipose Muscle Bone

60. According to NCRP regulations, leakage radiation rom the x-ray tube must not exceed (A) (B) (C) (D)

10 mR/h (0.1 m Gya/hr) 100 mR/h (1.0 m Gya/hr) 10 mR/min (0.1 m Gya/min) 100 mR/min (1.0 m Gya/min)

61. Patient dose during uoroscopy is a ected by the 56. Late e ects o radiation, whose incidence is dose related and or which there is no threshold dose, are re erred to as (A) (B) (C) (D)

nonstochastic/deterministic stochastic/probabilistic chromosomal aberration hematologic depression

57. What is used to illustrate the relationship between exposure to ionizing radiation and possible resultant biologic responses? (A) (B) (C) (D)

Ionization chamber T ermoluminescent dosimeter Dose–response curve Electromagnetic spectrum

58. Classi y the ollowing tissues in order o increasing radiosensitivity: 1. Liver cells 2. Intestinal crypt cells 3. Muscle cells (A) (B) (C) (D)

1, 3, 2 2, 3, 1 2, 1, 3 3, 1, 2

1. distance between the patient and the input phosphor 2. amount o magni cation 3. tissue density (A) (B) (C) (D)

1 only 3 only 2 and 3 only 1, 2, and 3

62. Which o the ollowing statements is (are) true with respect to radiation sa ety in uoroscopy? 1. abletop radiation intensity must not exceed 2.1 R/min/mA. 2. abletop radiation intensity must not exceed 10 R/min. 3. In high-level uoroscopy, tabletop intensity up to 20 R/min is permitted. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

63. T e symbols 130 56 Ba and which o the ollowing? (A) (B) (C) (D)

Isotopes Isobars Isotones Isomers

138 56

Ba are examples o

3: Radiation Protection

(A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

65. Which o the ollowing actors will a ect both the quality and the quantity o the primary beam? 1. Hal -value layer (HVL) 2. Kilovolts (kV) 3. Milliamperes (mA) (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

66. Which o the ollowing contributes most to occupational exposure? (A) (B) (C) (D)

T e photoelectric e ect Compton scatter Classic scatter T ompson scatter

67. Primary radiation barriers usually require which thickness o shielding? (A) ¼-inch lead (B) ⅛-inch lead (C) 116-inch lead (D) 1 32-inch lead

AP projection PA projection erect position supine position

70. According to the NCRP, the annual occupational dose-equivalent limit (50 rem) to the thyroid, skin, and extremities is (A) (B) (C) (D)

50 mSv 150 mSv 500 mSv 1,500 mSv

71. What is the relationship between LE and RBE? (A) (B) (C) (D)

As LE increases, RBE increases. As LE increases, RBE decreases. As LE decreases, RBE increases. T ere is no direct relationship between LE and RBE.

72. Which o the dose–response curve(s) shown in Figure 3-2 illustrate(s) a linear threshold response to radiation exposure? 1. Dose–response curve A 2. Dose–response curve B 3. Dose–response curve C (A) (B) (C) (D)

1 only 2 only 1 and 2 only 2 and 3 only

p s

300 mA, 250 ms, 70 kVp 300 mA, 125 ms, 80 kVp 400 mA, 90 ms, 80 kVp 600 mA, 30 ms, 90 kVp

e

(A) (B) (C) (D)

o

n

68. Which o the ollowing groups o technical actors will deliver the least patient dose?

(A) (B) (C) (D)

e

1. Incident electrons interacting with several layers o tungsten target atoms 2. Energy di erences among incident electrons 3. Electrons moving to ll di erent shell vacancies

69. For radiographic examinations o the skull, it is generally pre erred that the skull be examined in the

s

64. Which o the ollowing account(s) or an x-ray beam’s heterogeneity?

R

132

A

B

Dos e

Figure 3-2.

C

Questions: 64–81

73. T e NCRP recommends an annual e ective occupational dose-equivalent limit o (A) (B) (C) (D)

2.5 rem (25 mSv) 5 rem (50 mSv) 10 rem (100 mSv) 20 rem (200 mSv)

74. Which o the ollowing ormulas is a representation o the inverse-square law o radiation used to determine x-ray intensity at di erent distances? (A) (B)

D 22

I1 = 2 I2 D1

2 I1 D 1 = 2 I2 D 2

2 D kVp 2 1 (C) = 2 kVp2 D 1 2 D kVp 1 1 (D) = 2 kVp2 D 2

75. An increase o 1.0-mm added aluminum ltration o the x-ray beam would have which o the ollowing e ects? 1. Increase in average energy o the beam 2. Increase in patient skin dose 3. Increase in milliroentgen output (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

76. Aluminum ltration has its greatest e ect on (A) (B) (C) (D)

low-energy x-ray photons high-energy x-ray photons low-energy scattered photons high-energy scattered photons

77. T e amount o time that x-rays are being produced and directed toward a particular wall is re erred to as the (A) (B) (C) (D)

workload use actor occupancy actor controlling actor

133

78. T e operation o personnel radiation monitoring devices can depend on which o the ollowing? 1. Ionization 2. Luminescence 3. T ermoluminescence (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

79. Which o the ollowing result(s) rom restriction o the x-ray beam? 1. Less scattered radiation production 2. Less patient hazard 3. Less radiographic contrast (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

80. How will x-ray photon intensity be a ected i the source-to-image distance (SID) is doubled? (A) (B) (C) (D)

Its intensity increases two times. Its intensity increases our times. Its intensity decreases two times. Its intensity decreases our times.

81. Early symptoms o acute radiation syndrome include 1. leukopenia 2. nausea and vomiting 3. cataracts (A) (B) (C) (D)

1 and 2 only 2 only 1 and 3 only 2 and 3 only

134

3: Radiation Protection

82. Re erring to the nomogram in Figure 3-3, what is the approximate patient ESE rom an AP projection o the abdomen made at 105 cm using 70 kVp, 300 mA, 200 ms, and 2.5 mm Al total ltration? (A) (B) (C) (D)

5 mR 166 mR 245 mR 288 mR

84. Which o the ollowing re ers to a regular program o evaluation that ensures the proper unctioning o x-ray equipment, thereby protecting both radiation workers and patients? (A) (B) (C) (D)

Sensitometry Quality assurance Quality control Modulation trans er unction

85. T e Bucky slot cover is in place to protect the 1. patient 2. uoroscopist 3. technologist (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

86. Which type o personnel radiation monitor can provide an immediate reading? (A) (B) (C) (D)

T ermoluminescent dosimeter ( LD) Optically stimulated luminescence (OSL) Film badge Ionization chamber

87. Which o the ollowing terms is correctly used to describe x-ray beam quality? (A) (B) (C) (D) Figure 3-3. Reproduced, with permission, from McCullough EC, Cameron JR. Exposure rates from diagnostic x-ray units. Br J Radiol. 1970;43:448–451.

83. T e unit o measurement used to express occupational exposure is the (A) (B) (C) (D)

roentgen (C/kg) rad (Gy) rem (Sv) relative biologic e ectiveness (RBE)

mA HVL Intensity Dose rate

88. T e most e ective type o shield or anterior and lateral male gonadal protection during uoroscopy is (A) at contact (B) shaped contact (contour) (C) shadow (D) cylindrical 89. Isotopes are atoms that have the same (A) (B) (C) (D)

mass number but a di erent atomic number atomic number but a di erent mass number atomic number but a di erent neutron number atomic number and mass number

Questions: 82–98

90. I the ESE or a particular exposure is 25 mrad, what will be the intensity o the scattered beam perpendicular to and 1 m rom the patient? (A) (B) (C) (D)

25 mrad 2.5 mrad 0.25 mrad 0.025 mrad

91. T e likelihood o adverse radiation e ects to any radiographer whose dose is kept below the recommended guideline is (A) (B) (C) (D)

very probable possible very remote zero

92. Factors that contribute to the amount o scattered radiation produced include 1. radiation quality 2. eld size 3. grid ratio (A) (B) (C) (D)

95. According to the NCRP, the annual occupational whole-body dose-equivalent limit is (A) (B) (C) (D)

1 mSv 50 mSv 150 mSv 500 mSv

96. It is necessary to question a emale patient o childbearing age regarding her 1. date o last menstrual period 2. possibility o being pregnant 3. age at her rst pregnancy (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 2 and 3 only

97. Which o the dose–response curves seen in Figure 3-4 represents possible genetic e ects o ionizing radiation? (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Dose–response curve A Dose–response curve B Dose–response curve C None o these

93. T e SSD in mobile uoroscopy must be

s

p

o

n

s

e

15 in 15 in 12 in 12 in

e

a minimum o a maximum o a minimum o a maximum o

R

(A) (B) (C) (D)

94. T e automatic exposure device that is located immediately under the x-ray table is the (A) (B) (C) (D)

ionization chamber scintillation camera photomultiplier photocathode

135

A

B

C

Dos e

Figure 3-4.

98. What is the e ect on RBE as LE increases? (A) (B) (C) (D)

As LE increases, RBE increases. As LE increases, RBE decreases. As LE increases, RBE stabilizes. LE has no e ect on RBE.

136

3: Radiation Protection

99. Which o the ollowing would most likely result in the greatest skin dose? (A) (B) (C) (D)

1. T ey reduce the e ect o radiation exposure. 2. T ey permit cellular repair. 3. T ey allow tissue recovery.

Short SID High kVp Increased ltration Increased mA

100. Which o the ollowing radiation-induced conditions is most likely to have the longest latent period? (A) Leukemia (B) emporary in ertility (C) Erythema (D) Acute radiation lethality

10 MeV protons 5 MeV alpha particles Diagnostic x-rays Fast neutrons

Standing 3 Standing 8 Standing 5 Standing 6

rom the source rom the source rom the source rom the source

or 2 minutes or 2 minutes or 1 minute or 2 minutes

103. An optically stimulated luminescence dosimeter contains which o the ollowing detectors? (A) (B) (C) (D)

Gadolinium Aluminum oxide Lithium uoride Photographic lm

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

(A) (B) (C) (D)

an inner-shell electron an outer-shell electron a nucleus another photon

106. Filters used in radiographic x-ray tubes generally are composed o

102. I an individual receives 50 mR while standing 4 rom a source o radiation or 2 minutes, which o the ollowing option(s) will most e ectively reduce his or her radiation exposure to that source o radiation? (A) (B) (C) (D)

(A) (B) (C) (D)

105. T e photoelectric e ect is an interaction between an x-ray photon and

101. Which o the ollowing ionizing radiations is described as having an RBE o 1.0? (A) (B) (C) (D)

104. How do ractionation and protraction a ect radiation dose e ects?

(A) (B) (C) (D)

aluminum copper tin lead

107. All the ollowing unction to reduce patient dose except (A) (B) (C) (D)

beam restriction high kVp, low mAs actors a high-speed grid a high-speed imaging system

108. In the production o Bremsstrahlung radiation (A) the incident photon ejects an inner-shell tungsten electron. (B) the incident photon is de ected, with resulting energy loss. (C) the incident electron ejects an inner-shell tungsten electron. (D) the incident electron is de ected, with resulting energy loss.

Questions: 99–118

109. All the ollowing radiation-exposure responses exhibit a nonlinear threshold dose–response relationship except (A) (B) (C) (D)

skin erythema hematologic depression radiation lethality leukemia

110. Which o the ollowing is o en used to express exposure in air? (A) (B) (C) (D)

Roentgen (C/kg) Rad (Gy) Rem (Sv) RBE

111. T e purpose o (A) (B) (C) (D)

lters in a lm badge is

to eliminate harm ul rays to measure radiation quality to prevent exposure by alpha particles as a support or the lm contained within

112. How many HVLs are required to reduce the intensity o a beam o monoenergetic photons to less than 15% o its original value? (A) (B) (C) (D)

2 3 4 5

113. Which o the ollowing has (have) an e ect on the amount and type o radiation-induced tissue damage? 1. Quality o radiation 2. ype o tissue being irradiated 3. Fractionation (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

137

114. Radiation dose to personnel is reduced by which o the ollowing exposure control cord guidelines? 1. Exposure cords on xed equipment must be very short. 2. Exposure cords on mobile equipment should be airly long. 3. Exposure cords on xed and mobile equipment should be o the coiled, expandable type. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

115. Primary radiation barriers must be at least how high? (A) (B) (C) (D)

5 6 7 8

116. Which o the ollowing body parts is (are) included in whole-body dose? 1. Gonads 2. Blood- orming organs 3. Extremities (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

117. Which o the ollowing projections would deliver the largest thyroid dose? (A) (B) (C) (D)

AP skull PA skull PA esophagus PA chest

118. Which o the ollowing personnel monitoring devices used in diagnostic radiography is considered to be the most sensitive and accurate? (A) LD (B) Film badge (C) OSL dosimeter (D) Pocket dosimeter

138

3: Radiation Protection

119. Irradiation o macromolecules in vitro can result in 1. cleaved chromosome 2. cross-linking 3. mutation (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

120. Which o the ollowing radiation situations is potentially the most harm ul? (A) A large dose to a speci c area all at once. (B) A small dose to the whole body over a period o time. (C) A large dose to the whole body all at one time. (D) A small dose to a speci c area over a period o time. 121. How much protection is provided rom a 100-kVp x-ray beam when using a 0.50-mm lead equivalent apron? (A) (B) (C) (D)

40% 75% 88% 99%

122. Occupational radiation monitoring is required when it is likely that an individual will receive more than what raction o the annual dose limit? (A) ½ (B) ¼ (C) 110 (D) 1 40 123. T e interaction illustrated in Figure 3-5 1. can pose a sa ety hazard to personnel 2. can have a negative impact on image quality 3. occurs with low-energy incident photons (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Figure 3-5.

124. Biologic material is least sensitive to irradiation under which o the ollowing conditions? (A) (B) (C) (D)

Anoxic Hypoxic Oxygenated Deoxygenated

125. Which o the ollowing cells are the most radiosensitive? (A) (B) (C) (D)

Myelocytes Erythroblasts Megakaryocytes Myocytes

126. Which o the ollowing statements regarding the pregnant radiographer is (are) true? 1. She should declare her pregnancy to her supervisor. 2. She should be assigned a second personnel monitor. 3. Her radiation history should be reviewed. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Questions: 119–134

127. E ects o deoxyribonucleic acid (DNA) irradiation include 1. mitotic delay 2. reproductive death 3. chromosome breakage (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

T e photoelectric e ect Compton scatter Classic scatter T ompson scatter

129. Which o the ollowing statements is (are) true with respect to the dose–response curve shown in Figure 3-6? 1. T e quantity o radiation is directly related to the dose received. 2. No threshold is required or e ects to occur. 3. A minimum amount o radiation is required or mani estation o e ects. (A) (B) (C) (D)

130. T e classi cations o acute radiation syndrome include all the ollowing except (A) (B) (C) (D)

central nervous system gastrointestinal neonatal hematologic

131. In the production o characteristic radiation at the tungsten target, the incident electron

128. Which o the ollowing contributes most to patient dose? (A) (B) (C) (D)

139

1 only 1 and 2 only 1 and 3 only 2 and 3 only

(A) (B) (C) (D)

ejects an inner-shell tungsten electron ejects an outer-shell tungsten electron is de ected, with resulting energy loss is de ected, with resulting energy gain

132. Which o the ollowing de nes the gonadal dose that, i received by every member o the population, would be expected to produce the same total genetic e ect on that population as the actual doses received by each o the individuals? (A) (B) (C) (D)

Genetically signi cant dose Somatically signi cant dose Maximum permissible dose Lethal dose

133. I an exposure dose o 50 mR/h is delivered rom a distance o 3 , what would be the dose delivered a er 20 minutes at a distance o 5 rom the source? (A) (B) (C) (D)

6 mR 18 mR 46 mR 138 mR

134. T e term e ective dose re ers to (A) (B) (C) (D)

R

D

Figure 3-6.

whole-body dose localized organ dose genetic e ects somatic and genetic e ects

140

3: Radiation Protection

135. Which o the ollowing is (are) possible long-term somatic e ects o radiation exposure? 1. Blood changes 2. Cataractogenesis 3. Embryologic e ects (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

136. T e operation o personal radiation monitoring can be based on stimulated luminescence. Which o the ollowing personal radiation monitors unction(s) in that manner? 1. OSL dosimeter 2. LD 3. Pocket dosimeter (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

137. I a patient received 1,400 mrad during a 7-minute uoroscopic examination, what was the dose rate? (A) (B) (C) (D)

200 rad/min 5 rad/min 2.0 rad/min 0.2 rad/min

138. What is used to account or the di erences in tissue sensitivity to ionizing radiation when determining e ective dose E?

139. Which interaction between ionizing radiation and the target molecule involves ormation o a ree radical? (A) Direct e ect (B) Indirect e ect (C) arget e ect (D) Random e ect 140. T e single most important scattering object in both radiography and uoroscopy is the (A) (B) (C) (D)

x-ray table x-ray tube patient IR

141. All the ollowing statements regarding LDs are true except (A) LDs are reusable (B) a LD is a personal radiation monitor (C) LDs use a lithium uoride phosphor (D) a er x-ray exposure, LDs emit heat in response to stimulation by light 142. A student radiographer who is under 18 years o age must not receive an annual occupational dose o greater than (A) (B) (C) (D)

0.1 rem (1 mSv) 0.5 rem (5 mSv) 5 rem (50 mSv) 10 rem (100 mSv)

143. Sources o medical radiation exposure include

1. issue weighting actors (Wt) 2. Radiation weighting actors (Wr) 3. Absorbed dose

1. computed tomography 2. sonography 3. magnetic resonance imaging

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

Questions: 135–152

144. Which o the ollowing is (are) likely to improve image quality and decrease patient dose? 1. Beam restriction 2. Low–kilovolt and high–microampere-second actors 3. Grids (A) (B) (C) (D) 145.

1 only 1 and 3 only 2 and 3 only 1, 2, and 3

ypes o secondary radiation barriers include 1. the control booth 2. lead aprons 3. the x-ray tube housing (A) (B) (C) (D)

2 only 1 and 2 only 2 and 3 only 1, 2, and 3

146. Which o the ollowing radiation protection concepts/ measures apply to mobile radiography? 1. T e radiographer should be at least 6 rom the patient and the x-ray tube during the exposure. 2. T e least amount o scattered radiation is perpendicular to the scattering object. 3. At least one lead apron should be assigned to each mobile unit. (A) (B) (C) (D) 147.

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

ypes o structural damage to a DNA molecule by ionizing radiation include which o the ollowing? 1. Single-side-rail scission 2. Double-side-rail scission 3. Cross-linking (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

141

148. Which o the ollowing can be an e ective means o reducing radiation exposure? 1. Barriers 2. Distance 3. ime (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

149. T e e ects o radiation on biologic material depend on several actors. I a large quantity o radiation is delivered to a body over a short period o time, the e ect (A) will be greater than i it were delivered in increments (B) will be less than i it were delivered in increments (C) has no relation to how it is delivered in time (D) solely depends on the radiation quality 150. Somatic e ects o radiation re er to e ects that are mani ested (A) in the descendants o the exposed individual (B) during the li e o the exposed individual (C) in the exposed individual and his or her descendants (D) in the reproductive cells o the exposed individual 151. What minimum total amount o ltration (inherent plus added) is required in x-ray equipment operated above 70 kVp? (A) (B) (C) (D)

2.5-mm Al equivalent 3.5-mm Al equivalent 2.5-mm Cu equivalent 3.5-mm Cu equivalent

152. T e dose o radiation that will cause a noticeable skin reaction is re erred to as the (A) (B) (C) (D)

LE SSD SED SID

142

3: Radiation Protection

153. What is the intensity o scattered radiation perpendicular to and 1 m rom a patient compared with the use ul beam at the patient’s sur ace? (A) (B) (C) (D)

0.01% 0.1% 1.0% 10.0%

154. Some patients, such as in ants and children, are unable to maintain the necessary radiographic position without assistance. I mechanical restraining devices cannot be used, who o the ollowing should be the rst choice to help immobilize the patient? (A) ransporter (B) Patient’s ather (C) Patient’s mother (D) Student radiographer 155. A controlled area is de ned as one 1. that is occupied by people trained in radiation sa ety 2. that is occupied by people who wear radiation monitors 3. whose occupancy actor is 1 (A) (B) (C) (D)

1 and 2 only 2 only 1 and 3 only 1, 2, and 3

156. Which o the ollowing terms re ers to the period between conception and birth? (A) (B) (C) (D)

Gestation Congenital Neonatal In vitro

157. Somatic e ects resulting rom radiation exposure can 1. have possible consequences on the exposed individual 2. have possible consequences on uture generations 3. cause temporary in ertility (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 1, 2, and 3

158. I the image intensi er is moved arther rom the patient 1. SID increases 2. patient dose decreases 3. image quality improves (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

159. In which type o monitoring device do photons release electrons by their interaction with air? (A) Film badge (B) LD (C) Pocket dosimeter (D) OSL dosimeter 160. T e advantages o beam restriction include which o the ollowing? 1. Less scattered radiation is produced. 2. Less biologic material is irradiated. 3. Less total ltration will be necessary. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

161. T e person responsible or ascertaining that all radiation guidelines are adhered to and that personnel understand and employ radiation sa ety measures is the (A) (B) (C) (D)

radiology department manager radiation sa ety of cer chie radiologist chie technologist

162. T e dose–response curve that appears to be valid or genetic and some somatic e ects is the 1. linear 2. nonlinear 3. nonthreshold (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 1, 2, and 3

Questions: 153–172

163. Which o the ollowing statements regarding the human gonadal cells is (are) true? 1. T e emale oogonia reproduce only during etal li e. 2. T e male spermatogonia reproduce continuously. 3. Both male and emale stem cells reproduce only during etal li e. (A) (B) (C) (D)

1 only 2 only 1 and 2 only 3 only

164. With milliamperes (mA) increased to maintain output intensity, how is the ESE a ected as the source-to-skin distance (SSD) is increased? (A) (B) (C) (D)

T e ESE increases. T e ESE decreases. T e ESE remains unchanged. ESE is unrelated to SSD.

165. T e primary unction o (A) (B) (C) (D)

ltration is to reduce

patient skin dose operator dose image noise scattered radiation

166. Which o the ollowing actors can a ect the amount or the nature o radiation damage to biologic tissue? 1. Radiation quality 2. Absorbed dose 3. Size o irradiated area (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

167. Examples o stochastic/probabilistic e ects o radiation exposure include 1. radiation-induced malignancy 2. genetic e ects 3. leukemia (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

143

168. Which o the ollowing tissues is (are) considered to be particularly radiosensitive? 1. Intestinal mucous membrane 2. Epidermis o extremities 3. Optic nerves (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

169. Which o the ollowing groups o technical actors will deliver the least amount o exposure to the patient? (A) (B) (C) (D)

400 mA, 0.25 second, 100 kVp 600 mA, 0.33 second, 90 kVp 800 mA, 0.5 second, 80 kVp 800 mA, 1.0 second, 70 kVp

170. I the exposure rate to an individual standing 4.0 m rom a source o radiation is 10 mR/h, what will be the dose received a er 20 minutes at a distance o 6 m rom the source? (A) (B) (C) (D)

22.5 mR 7.5 mR 4.44 mR 1.48 mR

171. Which o the ollowing projections is most likely to deliver the largest dose to the ovaries? (A) (B) (C) (D)

AP lumbar spine, 7 × 17 inch IR, 80 kVp AP lumbar spine, 14 × 17 inch IR, 80 kVp AP abdomen, 80 kVp AP abdomen, 70 kVp

172. Under what circumstances might a radiographer be required to wear two dosimeters? 1. During pregnancy 2. While per orming vascular procedures 3. While per orming mobile radiography (A) (B) (C) (D)

1 and 2 only 2 only 2 and 3 only 1, 2, and 3

144

3: Radiation Protection

173. What quantity o radiation exposure to the reproductive organs is required to cause temporary in ertility? (A) (B) (C) (D)

100 rad 200 rad 300 rad 400 rad

(A) (B) (C) (D)

174. Which o the ollowing personnel radiation monitors will provide an immediate reading? (A) LD (B) Film badge (C) Lithium uoride chips (D) Pocket dosimeter

176. Which o the dose–response curves shown in Figure 3-7 is representative o radiation-induced skin erythema?

179. Radiation that passes through the tube housing in directions other than that o the use ul beam is termed (A) (B) (C) (D)

scattered radiation secondary radiation leakage radiation remnant radiation

180. T e presence o ionizing radiation may be detected in which o the ollowing ways? 1. Ionizing e ect on air 2. Photographic e ect on lm emulsion 3. Fluorescent e ect on certain crystals

1 only 1 and 2 only 3 only 2 and 3 only

(A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

181. Possible responses to irradiation in utero include

o

n

s

e

1. spontaneous abortion 2. congenital anomalies 3. childhood malignancies

p s e R

(A) (B) (C) (D)

the photoelectric e ect Compton scatter classic scatter pair production

uoroscopy

5 mR/min 10 R/min 10 mR/h 5 R/h

1. Dose–response curve A 2. Dose–response curve B 3. Dose–response curve C

7 mR 12 mR 14 mR 24 mR

178. Lead aprons are worn during uoroscopy to protect the radiographer rom exposure to radiation rom (A) (B) (C) (D)

175. T e tabletop exposure rate during shall not exceed (A) (B) (C) (D)

177. I the exposure rate at 3 rom the uoroscopic table is 40 mR/h, what will be the exposure rate or 30 minutes at a distance o 5 rom the table?

A

B

Dos e

Figure 3-7.

C

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3 only

Questions: 173–187

182. What should be the radiographer’s main objective regarding personal radiation sa ety? (A) Not to exceed his or her dose limit. (B) o keep personal exposure as ar below the dose limit as possible. (C) o avoid whole-body exposure. (D) o wear protective apparel when “holding” patients or exposures. 183. Re erring to the nomogram in Figure 3-8, what is the approximate patient ESE rom a particular projection made at 105 cm using 110 kVp, 300 mA, 5 ms, and 2.5 mm Al total ltration? (A) (B) (C) (D)

42 mR 18 mR 420 mR 180 mR

145

184. I the exposure rate to a body standing 7 rom a radiation source is 140 mR/h, what will be the dose to that body at a distance o 8 rom the source in 30 minutes? (A) (B) (C) (D)

182.8 mR 107 mR 91.4 mR 53.6 mR

185. Which o the ollowing types o radiation is (are) considered electromagnetic? 1. X-ray 2. Gamma 3. Beta (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

186. Which o the ollowing eatures o uoroscopic equipment is (are) designed especially to eliminate unnecessary radiation exposure to the patient and/ or personnel? 1. Bucky slot cover 2. Exposure switch/ oot pedal 3. Cumulative exposure timer (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

187. Radiation output rom a diagnostic x-ray tube is measured in which o the ollowing units o measurement? (A) (B) (C) (D)

Figure 3-8. Reproduced, with permission, from McCullough EC, Cameron JR. Exposure rates from diagnostic x-ray units. Br J Radiol. 1970;43:448–451.

Rad Rem Roentgen Becquerel

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3: Radiation Protection

188. Which o the ollowing is (are) considered especially radiosensitive tissues?

192. T e genetic dose o radiation borne by each member o the reproductive population is called the

1. Bone marrow 2. Intestinal crypt cells 3. Erythroblasts (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

(A) (B) (C) (D)

193. According to the NCRP, the pregnant radiographer’s gestational dose-equivalent limit or a 1-month period is

189. Which o the ollowing sa eguards is (are) taken to prevent inadvertent irradiation in early pregnancy? 1. Patient postings 2. Patient questionnaire 3. Elective booking (A) (B) (C) (D) 190.

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

he interaction between x-ray photons and tissue that is responsible or radiographic contrast but that also contributes signi icantly to patient dose is (A) (B) (C) (D)

the photoelectric e ect Compton scatter coherent scatter pair production

191. Which o the ollowing is (are) acceptable way(s) to monitor the radiation exposure o those who are occupationally employed? 1. LD 2. OSL dosimeter 3. Quarterly blood cell count (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

genetically related dose genetically signi cant dose somatic related dose somatic signi cant dose

(A) (B) (C) (D) 194.

1 mSv 5 mSv 0.1 mSv 0.5 mSv

o within what percentage o the SID must the collimator light and actual irradiated area be accurate? (A) (B) (C) (D)

2% 5% 10% 15%

195. T e correct way(s) to check or cracks in lead aprons is (are) 1. to uoroscope them once a year 2. to radiograph them at low kilovoltage twice a year 3. by visual inspection (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

196. T e target theory applies to (A) (B) (C) (D)

spermatogonia oocytes lymphocytes DNA molecules

Questions: 188–200

197. Which o the ollowing is (are) eatures o uoroscopic equipment designed especially to eliminate unnecessary radiation to patient and/or personnel? 1. Protective curtain 2. Filtration 3. Collimation (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

198. Which o the ollowing have been identi ed as source(s) o radon exposure? 1. Indoors, in houses 2. Smoking cigarettes 3. Radiology departments (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

147

199. T e skin response to radiation exposure, which appears as reddening o the irradiated skin area, is known as (A) (B) (C) (D)

dry desquamation moist desquamation erythema epilation

200. T e biologic e ect on an individual depends on which o the ollowing? 1. ype o tissue interaction(s) 2. Amount o interactions 3. Biologic di erences (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

Answers and Explanations

1. (C) Biologic tissue is more sensitive to radiation when it is in an oxygenated state. A characteristic o many avascular (and, there ore, hypoxic) tumors is their resistance to treatment with radiation. Hyperbaric (high-pressure oxygen) therapy is used in some therapy centers in an e ort to increase the sensitivity o the tissues being treated. 2. (B) T e pregnant radiographer poses a special radiation protection consideration, or the sa ety o the unborn individual. It must be remembered that the developing etus is particularly sensitive to radiation exposure. T ere ore, established guidelines state that the occupational gestational dose-equivalent limit or embryo/ etus o a pregnant radiographer is 5 mSv (500 mrem), not to exceed 0.5 mSv in 1 month. According to the NCRP, the annual occupational whole-body dose-equivalent limit is 50 mSv (5 rem or 5,000 mrem). T e annual occupational whole-body dose-equivalent limit or students under the age o 18 years is 1 mSv (100 mrem or 0.1 rem). T e annual occupational dose-equivalent limit or the lens o eye is 150 mSv (15 rem). T e annual occupational dose-equivalent limit or the thyroid, skin, and extremities is 500 mSv (50 rem). 3. (D) I the exposure rate or the examination is 250 mR/h (60 minutes), then a 3-minute examination would be proportionally less—as the ollowing equation illustrates: 275( mR ) x ( mR ) = 60( min ) 1.5( min ) 60x = 412.5 T us, x = 6.87-mR dose in 1.5 minutes.

148

4. (C) Late e ects o radiation can occur in cells that have survived a previous irradiation months or years earlier. T ese late e ects, such as carcinogenesis and genetic e ects, are “all-or-nothing” e ects—either the organism develops cancer or it does not. Most late e ects do not have a threshold dose; that is, any dose, however small, theoretically can induce an e ect. Increasing that dose will increase the likelihood o the occurrence but will not a ect its severity; these e ects are termed stochastic/probabilistic. Nonstochastic/deterministic e ects are those that will not occur below a particular threshold dose and that increase in severity as the dose increases. 5. (D) Humans have always been exposed to ionizing radiation. Some ionizing radiations occur naturally in the earth’s crust and in its atmosphere. T ese radiations are present in the structures in which we live and in the ood we consume; radioactive gas is present in the air that we breathe, and there are traces o radioactive minerals in our bodies. T ese radiations are re erred to as external and internal sources o natural background (environmental) radiation. Our largest source o natural background radiation exposure is to radon and thoron gasses. We are also exposed to sources o radiation created by humans. Arti cial or manmade radiation contributes to the dose received by the U.S. population. According to the BEIR VII report, medical and dental x-rays and nuclear medicine studies account or approximately 79% o the man-made radiation exposure in the United States. In addition, NCRP Report No. 160 states

Answers: 1–11

that medical radiation exposure now contributes 50% o the public’s exposure to ionizing radiation. NRC (Nuclear Regulatory Commission) regulations and radiation exposure limits are published in itle 10 o the Code o Federal Regulations (CFR), Part 20. 6. (D) Lymphocytes, a type o white blood cell concerned with the immune system, have the greatest radiosensitivity o all body cells. Spermatids are also highly radiosensitive, although not to the same degree as lymphocytes. Muscle cells have a airly low radiosensitivity, and nerve cells are the least radiosensitive in the body (in etal li e, however, nerve cells are highly radiosensitive). 7. (B) It is our pro essional responsibility to minimize exposure dose to both patients and ourselves, and one o the most important ways is with a closely collimated radiation eld. Gonadal shielding should be used when the patient is o reproductive age or younger, when the gonads are in or near the collimated eld, and when the clinical objectives will not be compromised. 8. (B) T e principal interactions that occur between x-ray photons and body tissues in the diagnostic x-ray range, the photoelectric e ect and Compton scatter, are ionization processes producing photoelectrons and recoil electrons that traverse tissue and subsequently ionize molecules. T ese interactions occur randomly but can lead to molecular damage in the orm o impaired unction or cell death. T e target theory speci es that DNA molecules are the targets o greatest importance and sensitivity; that is, DNA is the key sensitive molecule. However, since the body has 65% to 80% water, most interactions between ionizing radiation and body cells will involve radiolysis o water rather than direct interaction with DNA. T e two major types o e ects that occur are the direct e ect and the indirect e ect. T e direct e ect usually occurs with high-LE radiations and when ionization occurs at the DNA molecule itsel . T e indirect e ect, which occurs most requently, happens when ionization takes place away rom the DNA molecule in cellular water. However, the energy rom the interaction can be trans erred to the molecule via a ree radical ( ormed by radiolysis o cellular water). Possible

149

damage to the DNA molecule is diverse. A single main-chain/side-rail scission (break) on the DNA molecule is repairable. A double mainchain/side-rail scission may repair with dif culty or may result in cell death. A double main-chain/ side-rail scission on the same “rung” o the DNA ladder results in irreparable damage or cell death. Faulty repair o main-chain breakage can result in cross-linking. Damage to the nitrogenous bases, that is, damage to the base itsel or to the rungs connecting the main chains, can result in alteration o base sequences, causing a molecular lesion/point mutation. Any subsequent divisions result in daughter cells with incorrect genetic in ormation. 9. (D) Humans have always been exposed to ionizing radiation. Some ionizing radiations (such as those emitted by uranium) occur naturally in the earth’s crust and in its atmosphere ( rom the sun and cosmic reactions in space). T ese radiations are present in the structures in which we live and in the ood we consume; radioactive gas is present in the air that we breathe, and there are traces o radioactive minerals in our bodies. T ese radiations are re erred to as external and internal sources o natural background (environmental) radiation. T e levels o natural background radiation can vary greatly rom one geographic location to another. Our largest source o natural background radiation exposure is to radon and thoron gasses. 10. (C) T e term kerma is used to express kinetic energy released in matter. X-rays expend kinetic energy as they ionize the air or matter. Joule/kilogram is used to measure air kerma and 1 J/kg = 1 Gya. T e subscript a represents air as the absorber. T e mGya is the Standard International (SI) unit o measure o radiation intensity. T e rad has been described as equivalent to 100 ergs o energy deposited per gram o irradiated material. T e SI unit is Gray (Gyt)—the subscript t representing tissue. 11. (C) Radiation e ects that appear days or weeks ollowing exposure (early e ects) are in response to high radiation doses; this is called acute radiation syndrome. T ese e ects should never occur in diagnostic radiology; they occur only in response

150

3: Radiation Protection

to much greater doses. Suf cient exposure o the hematologic system to ionizing radiation can result in nausea, vomiting, diarrhea, decreased blood cells count, and in ection. Very large exposure o the GI system (1,000–5,000 rad) causes severe damage to the (stem) cells lining the GI tract. T is can result in nausea, vomiting, diarrhea, blood changes, and hemorrhage. Exposure greater than 5,000 rad is required to a ect the normally resilient CNS. 12. (B) According to the NCRP, the annual occupational whole-body dose-equivalent limit is 50 mSv (5 rem or 5,000 mrem). T e annual occupational whole-body dose-equivalent limit or students under the age o 18 years is 1 mSv (100 mrem or 0.1 rem). T e annual occupational dose-equivalent limit or the lens o eye is 150 mSv (15 rem). T e annual occupational dose-equivalent limit or the thyroid, skin, and extremities is 500 mSv (50 rem). 13. (C) Di erent types o monitoring devices are available or the occupationally exposed, and anyone who might receive more than one-tenth the annual dose limit must be monitored. Ionization is the undamental principle o operation o both the lm badge and the pocket dosimeter. In the lm badge, the lm’s silver halide emulsion is ionized by x-ray photons. T e pocket dosimeter contains an ionization chamber (containing air), and the number o ions ormed (o either sign) is equated to exposure dose. LDs are radiation monitors that use lithium uoride crystals. Once exposed to ionizing radiation and then heated, these crystals give o light in proportion to the amount o radiation received. OSL dosimeters are radiation monitors that use aluminum oxide crystals. T ese crystals, once exposed to ionizing radiation and then subjected to a laser, give o luminescence proportional to the amount o radiation received. 14. (C) T e entire population o the world is exposed to varying amounts o background (environmental) radiation. Sources o background radiation are either natural or human-made. Exposure to natural background radiation is a result o cosmic radiation rom space (external terrestrial) and naturally radioactive elements within the earth’s crust (internal terrestrial) and our own bodies (internal sources, rom ingested materials). Naturally, the closer we are to the cosmic radiations rom space, the greater our personal exposure will be; living at higher

elevations and air travel expose us to greater amounts o radiation. Living or working in a building made o materials derived rom the ground exposes us to some background radiation rom the naturally radioactive elements ound in the earth’s crust. T e ood we eat, the water we drink, and the air we breathe all contribute to the quantity o radiation we ingest and inhale. Human-made radiation, however, is the type o background radiation over which we have some control. Medical and dental x-rays, nuclear power plant environs, and nuclear medicine contribute to our exposure to human-made background radiation. 15. (B) Radiolysis has to do with the irradiation o water molecules and the ormation o ree radicals. Free radicals contain enough energy to damage other molecules some distance away. T ey can migrate to and damage a DNA molecule (indirect hit theory). 16. (A) X-radiation used or diagnostic purposes is o relatively low energy. Kilovoltages o up to 150 kV are used, as compared with radiations having energies o up to several million volts. Linear energy trans er (LE ) re ers to the rate at which energy is trans erred rom ionizing radiation to so tissue. Particulate radiations, such as alpha particles, have mass and charge and, there ore, lose energy rapidly as they penetrate only a ew centimeters o air. X- and gamma radiations, having no mass or charge, are low-LE radiations. 17. (A) T e tissue weighting actor (Wt) represents the relative tissue radiosensitivity o irradiated material (e.g., muscle vs. intestinal epithelium vs. bone). T e radiation weighting actor (Wr) is a number assigned to di erent types o ionizing radiations in order to better determine their e ect on tissue (e.g., x-ray vs. alpha particles). T e Wr o di erent ionizing radiations depends on the LE o that particular radiation. T e ollowing ormula is used to determine e ective dose E: E ective dose E = radiation weighting actor Wr × tissue weighting actor Wt × absorbed dose 18. (B) In the photoelectric e ect, a relatively lowenergy photon uses all its energy to eject an innershell electron, leaving a vacancy. An electron rom

Answers: 12–25

151

the shell above drops down to ll the vacancy and in so doing gives up a characteristic ray. T is type o interaction is most harm ul to the patient because all the photon energy is trans erred to tissue. In Compton scatter, a high-energy incident photon ejects an outer-shell electron. In doing so, the incident photon is de ected with reduced energy, but it usually retains most o its energy and exits the body as an energetic scattered ray. T is scattered ray will either contribute to image og or pose a radiation hazard to personnel depending on its direction o exit. In classic scatter, a low-energy photon interacts with an atom but causes no ionization; the incident photon disappears into the atom and then is released immediately as a photon o identical energy but with changed direction. T ompson scatter is another name or classic scatter.

skin cancers are examples o carcinogenic somatic e ects o radiation. Another example o somatic e ects o radiation is cataract ormation to the lenses o eyes o individuals accidentally exposed to suf cient quantities o radiation. T e lives o many o the early radiation workers were several years shorter than the lives o the general population. Statistics revealed that radiologists, or example, had a shorter li e span than physicians o other specialties. Li e-span shortening, then, was another somatic e ect o radiation. Certainly, these e ects should never be experienced today. T e human reproductive organs are particularly radiosensitive. Fertility and heredity can be greatly a ected by the germ cells produced within the testes (spermatogonia) and ovaries (oogonia). Excessive radiation exposure to the gonads can cause temporary or permanent sterility and/or genetic mutations.

19. (B) T e relationship between x-ray intensity and distance rom the source is expressed by the inverse-square law o radiation. T e ormula is

22. (D) One o the radiation protection guidelines or the occupationally exposed is that the x-ray beam should scatter twice be ore reaching the operator. Each time the x-ray beam scatters, its intensity at 1 m rom the scattering object is one-thousandth o its original intensity. O course, the operator should be behind a shielded booth while making the exposure, but multiple scatterings urther reduce the danger o exposure rom scattered radiation.

2 I1 D 2 = 2 I2 D1

Substituting known values: 16 R h x 2 = 6 R h 16 6x 2 = 256 x 2 = 42.66 T us, x = 6.5 (necessary to decrease the exposure to 6 R/h). Note that in order or the exposure rate to decrease, the distance rom the source o radiation must increase. 20. (A) Protective apparel unctions to protect the occupationally exposed person rom scattered radiation only. Lead aprons and lead gloves do not protect rom the primary beam. No one in the radiographic room except the patient must ever be exposed to the primary beam. T e occupationally exposed and those ( amily and riends) who might assist a patient during an examination must wear protective apparel and keep out o the way o the primary beam. 21. (D) Late somatic e ects are those that can occur years a er initial exposure and are caused by low, chronic exposures. Occupationally exposed personnel are concerned with the late e ects o radiation exposure. Bone malignancies, thyroid cancers, leukemia, and

23. (C) Bergonié and ribondeau were French scientists who, in 1906, theorized what has now become veri ed law. Cells are more radiosensitive i they are immature (undi erentiated or stem) cells, i they are highly mitotic (having a high rate o proli eration), and i the irradiated tissue is young. Cells and tissues that are still undergoing development are more radiosensitive than ully developed tissues. 24. (C) LDs are personnel radiation monitors that use lithium uoride crystals. Once exposed to ionizing radiation and then heated, these crystals give o light proportional to the amount o radiation received. LDs are very accurate personal monitors. Even more accurate are optically stimulated luminescence (OSL) dosimeters. OSL dosimeters use aluminum oxide as their sensitive crystal. Silver halide is in lm emulsion and sodium thiosul ate is in xer solution. 25. (C) Secondary radiation consists o leakage and scattered radiation. Leakage radiation can be emitted when a de ect exists in the tube housing. A

152

3: Radiation Protection

signi cant quantity o scattered radiation is generated within, and emitted rom, the patient. Background radiation is naturally occurring radiation that is emitted rom the earth and that also exists within our bodies. 26. (C) T e selected milliampere-seconds is directly related to patient dose. T at is, i milliampere-seconds are doubled, patient dose is doubled. Similarly, i milliampere-seconds are cut in hal , patient dose is cut in hal . T e selected kilovolts peak is inversely related to patient dose. T at is, i the kilovolts peak is increased, patient dose can be decreased because more x-ray photons are transmitted through the patient rather than being absorbed. Inherent ltration is provided by materials that are a permanent part o the tube housing, that is, the glass envelope o the x-ray tube and the oil coolant. Added ltration, usually thin sheets o aluminum, is present to make a total o 2.5-mm Al equivalent or equipment operated above 70 kVp. Filtration is used to decrease patient dose by removing the weak x-rays that have no value but contribute to the skin dose. T e e ect o ocal spot size is principally on radiographic sharpness; it has no e ect on patient dose. 27. (B) T e photoelectric e ect is the interaction between x-ray photons and matter that is largely responsible or patient dose. T e photoelectric e ect occurs when a relatively low-energy photon uses all its energy to eject an inner-shell electron. T at electron is ejected rom the atom, leaving a hole in, or example, the K shell. An L-shell electron then drops down to ll the K vacancy and in so doing emits a characteristic ray whose energy equals the di erence in binding energies or the K and L shells. T e photoelectric e ect occurs with high–atomic-number (Z) absorbers such as bone and with positive contrast media. 28. (B) Aluminum lters are used to decrease patient skin dose by absorbing the low-energy photons (there ore, decreased milliroentgen output) that do not contribute to the image but do contribute to patient skin dose. HVL is de ned as that thickness o any absorber that will decrease the intensity o a particular beam to one-hal its original value. As ltration o an x-ray beam is increased, the overall average energy o the resulting beam is greater (because the low-energy photons have been removed)—and, there ore, the HVL thickness required would be greater.

29. (C) T e tissue weighting actor (Wt ) represents the relative tissue radiosensitivity o irradiated material (e.g., muscle vs. intestinal epithelium vs. bone). T e radiation weighting actor (Wr ) is a number assigned to di erent types o ionizing radiations in order to better determine their e ect on tissue (e.g., x-ray vs. alpha particles). T e Wr o di erent ionizing radiations depends on the LE o that particular radiation. T e ollowing ormula is used to determine e ective dose (E D): E ective dose (E D) = radiation weighting actor Wr × tissue weighting actor Wt × absorbed dose 30. (B) Special arrangements are required or occupational monitoring o the pregnant radiographer. T e pregnant radiographer will wear two dosimeters—one in its usual place at the collar and the other, a baby/ etal dosimeter, worn over the abdomen and under the lead apron during uoroscopy. T e baby/ etal dosimeter must be identi ed as such and always must be worn in the same place. Care must be taken not to mix the positions o the two dosimeters. T e dosimeters are read monthly, as usual. T e pregnant radiographer may not be made to leave the radiation area/department because o her pregnancy. 31. (A) Occupationally exposed individuals are required to use devices that will record and provide documentation o the radiation they receive over a given period o time, traditionally 1 month. T e most commonly used personal dosimeters are the OSL, the LD, and the lm badge. T ese devices must be worn only or documentation o occupational exposure. T ey must not be worn or any medical or dental x-rays one receives as a patient, and they are not used to measure naturally occurring background radiation. 32. (B) Irradiation during pregnancy, especially in early pregnancy, must be avoided. T e etus is particularly radiosensitive during the rst trimester, during much o which time pregnancy may not even be suspected. High-risk examinations include pelvis, hip, emur, lumbar spine, cystograms and urograms, and upper and lower gastrointestinal (GI) series. During the rst trimester, speci cally the 2nd to 10th weeks o pregnancy (i.e., during major organogenesis), i the radiation dose is

Answers: 26–41

suf cient, etal anomalies can be produced. Skeletal and/or organ anomalies can appear i irradiation occurs in the early part o this time period, and neurologic anomalies can be ormed in the latter part; mental retardation and childhood malignant diseases, such as cancers or leukemia, and retarded growth/development also can result rom irradiation during the rst trimester. Fetal irradiation during the second and third trimesters is not likely to produce anomalies but rather, with suf cient dose, some type o childhood malignant disease. Fetal irradiation during the rst 2 weeks o gestation can result in embryonic resorption or spontaneous abortion. It must be emphasized, however, that the likelihood o producing etal anomalies at doses below 20 rad is exceedingly small and that most general diagnostic examinations are likely to deliver etal doses o less than 1 to 2 rad. 33. (B) T e e ects o a quantity o radiation delivered to a body depend on the amount o radiation received, the size o the irradiated area, and how the radiation is delivered in time. I the radiation is delivered in portions over a period o time, it is said to be ractionated and has a less harm ul e ect than i it were delivered all at once because cells have an opportunity to repair, and some recovery occurs between doses. 34. (D) X-ray intensity is inversely related to SID; as SID increases, x-ray intensity decreases. T e x-ray intensity at the image intensi er also depends on the SID. Moving the image intensi er closer to the patient decreases the SID and increases x-ray beam intensity at the input phosphor. T e automatic brightness control (ABC) then decreases the mA thereby decreasing patient dose. Moving the image intensi er closer to the patient also results in a shorter OID, there ore decreased magni cation and improved image quality. 35. (A) Nondividing, di erentiated cells are specialized, mature cells that do not undergo mitosis. Having these qualities, they are rendered radioresistant, according to the theory proposed by Bergonié and ribondeau. T e adult nervous system is composed o nondividing, di erentiated cells and thus is the most radioresistant system in the adult. Epithelial tissue and lymphocytes contain many precursor stem cells and hence are among the most radiosensitive cells in the body.

153

36. (A) X-rays produced at the tungsten target make up a heterogeneous primary beam. Filtration serves to eliminate the so er, less penetrating photons, leaving an x-ray beam o higher average energy. Filtration is important in patient protection because un ltered, low-energy photons that are not energetic enough to reach the IR stay in the body and contribute to total patient dose. 37. (C) Lead aprons are secondary radiation barriers and must contain at least 0.25-mm Pb equivalent (according to CFR 20), usually in the orm o lead-impregnated vinyl. Many radiology departments routinely use lead aprons containing 0.5 mm Pb (the NCRP recommends 0.5-mm Pb equivalent minimum). T ese aprons are heavier, but they attenuate a higher percentage o scattered radiation. 38. (C) T e most radiosensitive portion o the GI tract is the small bowel. Projecting rom the lining o the small bowel are villi, rom the intestinal crypt cells o Lieberkühn, which are responsible or the absorption o nutrients into the bloodstream. Because the cells o the villi are continually being cast o , new cells must continually arise rom the crypts o Lieberkühn. Being highly mitotic undi erentiated stem cells, they are very radiosensitive. T us, the small bowel is the most radiosensitive portion o the GI tract. 39. (B) Cells are requently identi ed by their stage o development. Immature cells may be re erred to as undi erentiated or stem cells. Immature cells are much more radiosensitive than mature cells. 40. (B) Scattering occurs when there is partial trans er o the proton’s energy to matter, as in the Compton e ect. Absorption occurs when an x-ray photon interacts with matter and disappears, as in the photoelectric e ect. T e reduction in the intensity (quantity) o an x-ray beam as it passes through matter is termed attenuation. Divergence re ers to a directional characteristic o the x-ray beam as it is emitted rom the ocal spot. 41. (D) Part compression, when possible, can improve spatial resolution by reducing part thickness and decreasing OID. Contrast resolution is improved because less scattered radiation will be generated in a thinner part. Because the part is essentially thinner, technical actors can be reduced thereby decreasing patient dose.

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3: Radiation Protection

42. (D) For radiation sa ety, the uoroscopy exposure switch must be o the “dead man” type. When the oot is removed rom the uoro pedal, the “dead man” switch will terminate the exposure immediately. T ere must also be a uoroscopy timer that will either sound or interrupt exposure a er 5 minutes o uoroscopy. 43. (B) Protective barriers are classi ed as either primary or secondary. Primary barriers protect rom the use ul, or primary, x-ray beam and consist o a certain thickness o lead. T ey are located anywhere that the primary beam can possibly be directed, or example, the walls o the x-ray room. T e walls o the x-ray room usually require a 116 -in (1.5-mm) thickness o lead and should be 7 high. Secondary barriers protect rom secondary (scattered and leakage) radiation. Secondary barriers are control booths, lead aprons, gloves, and the wall o the x-ray room above 7 . Secondary barriers require much less lead than primary barriers. 44. (C) T e occupational dose limit is valid or beta, x-, and gamma radiations. Because alpha radiation is so rapidly ionizing, traditional personnel monitors will not record alpha radiation. However, because alpha particles are capable o penetrating only a ew centimeters o air, they are practically harmless as an external source. 45. (B) Diagnostic x-ray photons interact with tissue in a number o ways, but most requently they are involved in the production o Compton scatter or in a photoelectric interaction. T e photoelectric e ect is shown in Figure 3-9; it occurs when a relatively low-energy x-ray photon uses all its energy to eject an inner-shell electron. T at electron is ejected

Eje cte d photoe le ctron

Incide nt photon (low e ne rgy)

Figure 3-9.

(photoelectron) rom the innermost (K) shell, leaving a “hole” in the K shell and producing a positive ion. An L-shell electron then drops down to ll the K vacancy and in so doing emits a characteristic ray whose energy is equal to the di erence between the binding energies o the K and L shells. T e photoelectric e ect occurs with high–atomic-number absorbers such as bone and positive contrast media and is responsible or the production o contrast. T ere ore, its occurrence is help ul or the production o the radiographic image, but it contributes signi cantly to the dose received by the patient (because it involves complete absorption o the incident photon). Scattered radiation, which produces a radiation hazard to the radiographer (as in uoroscopy), is a product o the Compton scatter interaction occurring with higher-energy x-ray photons. 46. (B) During uoroscopic procedures, as eld o view (FOV) decreases, magni cation o the output screen image increases, and contrast and resolution improve. T e ocal point on an image intensier’s 6-in eld/mode is urther away rom the output phosphor than the ocal point on the normal mode; there ore, the output image is magnied. Because less mini cation takes place, the image is not as bright. Exposure actors are increased automatically to compensate or the loss in brightness with smaller FOVs. Focal spot size (FSS) is unrelated to patient dose. 47. (D) Gonadal shielding should be used whenever appropriate and possible during radiographic and uoroscopic examinations. Flat contact shields are use ul or simple recumbent (AP, PA) studies, but when the examination necessitates obtaining oblique, lateral, or erect projections, they become less ef cient. Shaped contact (contour) shields are best because they enclose the male reproductive organs and remain in position in oblique, lateral, and erect positions. Shadow shields that attach to the tube head are particularly use ul or surgical sterile elds. 48. (C) Rad is an acronym or radiation absorbed dose; it measures the energy deposited in any material. Roentgen is the unit o exposure; it is o en used to express the quantity o ionizations in air as a traditional unit o measure. Rem is an acronym or radiation-equivalent man; it includes the RBE

Answers: 42–56

speci c to the tissue irradiated and, there ore, is a valid unit o measurement or the dose to biologic tissue. 49. (B) When biologic material is irradiated, there are a number o modi ying actors that determine what kind and how much response will occur in the material. One o these actors is LE , which expresses the rate at which particulate or photon energy is trans erred to the absorber. Because di erent kinds o radiation have di erent degrees o penetration in di erent materials, it is also a use ul way o expressing the quality o the radiation. 50. (C) Electromagnetic radiations such as x-rays and gamma rays are considered low-LE radiations because they produce ewer ionizations than the highly ionizing particulate radiations such as alpha particles. Alpha particles are large and heavy (two protons and two neutrons), and although they possess a great deal o kinetic energy (approximately 5 MeV), their energy is lost rapidly through multiple ionizations (approximately 40,000 atoms/cm o air). As an external source, alpha particles are almost harmless because they ionize the air very quickly and never reach the individual. As internal sources, however, they ionize tissues and are potentially the most harm ul. It may be stated that the alpha particle has one o the highest LE s o all ionizing radiations. 51. (D) T e various skin responses to irradiation include all our choices. T e rst noticeable response would be erythema, a reddening o the skin very much like sunburn. Dry desquamation could ollow; it is a dry peeling o the skin. Moist desquamation is peeling with associated pus-like uid. Epilation is hair loss; it can be temporary or permanent depending on sensitivity and dose. 52. (D) Occupationally exposed individuals are concerned principally with late (i.e., long-term or delayed) e ects o ionizing radiation such as radiation-induced genetic e ects, leukemia, and cancers (e.g., bone, lung, thyroid, and breast), as well as local e ects, such as skin erythema, in ertility, and cataracts—these can occur many years ollowing initial exposure to low levels o ionizing radiation. T e long-term/delayed e ects usually are chronic, and many are represented by the linear, nonthreshold dose–response curve.

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53. (C) T e reduction in the intensity (quantity) o an x-ray beam as it passes through matter as a result o absorption and scatter is called attenuation. Absorption occurs when an x-ray photon interacts with matter and disappears, as in the photoelectric e ect. Scattering occurs when there is partial transer o energy to matter, as in the Compton e ect. 54. (C) Radiation-induced malignancy, leukemia, and genetic e ects are late e ects (or stochastic/ probabilistic e ects) o radiation exposure. T ese can occur years a er survival o an acute radiation dose or a er exposure to low levels o radiation over a long period o time. Radiation workers need to be especially aware o the late e ects o radiation because their exposure to radiation is usually low level over a long period o time. Occupational radiation protection guidelines, there ore, are based on late e ects o radiation according to a linear, nonthreshold dose–response curve. 55. (C) During the rst trimester, speci cally the second through eighth weeks o pregnancy (during major organogenesis), i the radiation dose is at least 20 rad, etal anomalies can be produced. Skeletal anomalies usually appear i irradiation occurs in the early part o this time period, and neurologic anomalies are ormed in the latter part; mental retardation and childhood malignant diseases, such as cancers or leukemia, also can result rom irradiation during the rst trimester. Fetal irradiation during the second and third trimesters is not likely to produce anomalies but rather, with suf cient dose, some type o childhood malignant disease. Fetal irradiation during the rst 2 weeks o gestation can result in spontaneous abortion. It must be emphasized that the likelihood o producing etal anomalies at doses below 20 rad is exceedingly small and that most general diagnostic examinations are likely to deliver etal doses o less than 1 to 2 rad. 56. (B) Late or long-term e ects o radiation can occur in tissues that have survived a previous irradiation months or years earlier. T ese late e ects, such as carcinogenesis and genetic e ects, are “all-or-nothing” e ects—either the organism develops cancer or it does not. Most late e ects do not have a threshold dose; that is, any dose, however small, can induce an e ect. Increasing that dose will increase the likelihood o the occurrence

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but will not a ect its severity; these e ects are termed stochastic/probabilistic. Nonstochastic/ deterministic e ects are those that will not occur below a particular threshold dose and that increase in severity as the dose increases. Early e ects o radiation exposure are in response to relatively high radiation doses. T ese should never occur in diagnostic radiology; they occur only in response to doses much greater than those used in diagnostic radiology. One o the e ects that may be noted in such a circumstance is the hematologic e ect—reduced numbers o white blood cells, red blood cells, and platelets in the circulating blood. Immediate local tissue e ects can include e ects on the gonads (temporary in ertility) and on the skin (epilation, erythema). Acute radiation lethality, or radiation death, occurs a er an acute exposure and results in death in weeks or days. 57. (C) Although humans are exposed to ionizing radiation rom both natural and manmade sources, very high doses o manmade ionizing radiation can cause tissue damage that can mani est within days a er exposure. Late e ects such as cancer, which can occur a er more ordinary doses, may take many years to develop. T e association between a dose o ionizing radiation and the magnitude o the resulting response or e ect is re erred to as a dose–response, or dose–e ect, relationship. Dose– response curves are used to illustrate the relationship between exposure to ionizing radiation and possible resultant biologic responses. Ionization chambers and thermoluminescent dosimeters are used to detect and quanti y an individual’s exposure to ionizing radiation. T e electromagnetic spectrum identi es the various types o wavelike uctuations o electric and magnetic elds. 58. (D) According to Bergonié and ribondeau, the most radiosensitive cells are undi erentiated, rapidly dividing cells, such as lymphocytes, intestinal crypt (o Lieberkühn) cells, and spermatogonia. Liver cells are among the types o cells that are somewhat di erentiated and capable o mitosis. T ese characteristics render them somewhat radiosensitive. Muscle cells, as well as nerve cells and red blood cells, are highly di erentiated and do not divide. T ere ore, in order o increasing sensitivity ( rom least to greatest sensitivity), the cells are muscle, liver, and then intestinal crypt cells.

59. (D) Our bodies contain a variety o tissues having a variety o tissue densities. T ese tissues densities a ord di ering degrees o resistance to the passage o x-ray photons. issues having greater density absorb more o the x-ray beam (recall the photoelectric e ect). So tissues are airly easily penetrated to varying degrees; that is, lung and adipose are easier to penetrate than muscle. Bone has much higher tissue mass density and, there ore, absorbs more o the x-ray beam. 60. (B) X-ray photons produced in the x-ray tube can radiate in directions other than the one desired. T e tube housing, there ore, is constructed so that very little o this leakage radiation is permitted to escape. T e regulation states that leakage radiation must not exceed 100 mR/h at 1 m while the tube is operated at maximum potential. 61. (D) Moving the image intensi er closer to the patient during uoroscopy decreases the SID and patient dose (as SID is reduced, the intensity o the x-ray photons at the image intensi er’s input phosphor increases; the automatic brightness control then automatically decreases the milliamperage and, there ore, patient dose). Moving the image intensier closer to the patient during uoroscopy also decreases the OID and, there ore, magni cation. As tissue density increases, a greater exposure dose is required. 62. (D) In uoroscopy, the source o x-rays is 12 to 15 in below the x-ray tabletop. Since the source to object distance (SOD) is so short, patient skin dose can be quite high. Consequently, the x-ray intensity at the tabletop is limited to keep patient dose (ESE) within sa e limits. T e radiation protection guidelines state that x-ray intensity at tabletop must not exceed 2.1 R/ min/mA at 80 kVp. In equipment without high-level uoroscopy capability, the guideline can be expressed as 10 R/min tabletop limit. In equipment with highlevel uoroscopy capability, the tabletop limit is 20 R/min. 138 63. (A) 130 Ba and 56 56 Ba are isotopes o the same element, barium (Ba), because they have the same atomic number but di erent mass numbers (numbers o neutrons). Isobars are atoms with the same mass number but di erent atomic numbers. Isotones have the same number o neutrons but di erent atomic numbers. Isomers have the

Answers: 57–69

same atomic number and mass number; they are identical atoms existing at di erent energy states. 64. (D) T e x-ray photons produced at the tungsten target make up a heterogeneous beam, a spectrum o photon energies. T is is accounted or by the act that the incident electrons have di ering energies. Also, the incident electrons travel through several layers o tungsten target material, lose energy with each interaction, and, there ore, produce increasingly weaker photons. During characteristic x-ray production, vacancies may be lled in the K, L, or M shells, which di er rom each other in binding energies, and, there ore, photons with varying amounts o energy are emitted. 65. (B) Kilovoltage (kV) and the hal -value layer (HVL) e ect a change in both the quantity and the quality o the primary beam. T e principal qualitative actor o the primary beam is kilo-voltage, but an increase in kilovoltage will also increase the number o photons produced at the target. HVL, de ned as the amount o material necessary to decrease the intensity o the beam to one-hal , thereore changes both beam quality and beam quantity. Milliamperage is directly proportional to x-ray intensity (quantity) but is unrelated to the quality o the beam. 66. (B) In the photoelectric e ect, a relatively lowenergy photon uses all its energy to eject an innershell electron, leaving a vacancy. An electron rom the shell above drops down to ll the vacancy and in so doing gives up a characteristic ray. T is type o interaction is most harm ul to the patient because all the photon energy is trans erred to tissue. In Compton scatter, a high-energy incident photon uses some o its energy to eject an outer-shell electron. In so doing, the incident photon is de ected with reduced energy, but it usually retains most o its energy and exits the body as an energetic scattered ray. T is scattered ray will either contribute to image og or pose a radiation hazard to personnel depending on its direction o exit; thus, Compton scatter contributes the most to occupational exposure. In classic scatter, a low-energy photon interacts with an atom but causes no ionization; the incident photon disappears into the atom and then is released immediately as a photon o identical energy but with changed direction. T ompson scatter is another name or classic scatter.

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67. (C) Examples o primary barriers are the lead walls and doors o a radiographic room, that is, any sur ace that could be struck by the use ul beam. Primary protective barriers o typical installations generally consist o walls with 116 in (1.5 mm) o lead and 7 high. Secondary radiation is de ned as leakage and/or scattered radiation. T e x-ray tube housing protects rom leakage radiation, as stated earlier. T e patient is the source o most scattered radiation. Secondary radiation barriers include that portion o the walls above 7 in height; this area requires only 1 32 in o lead. T e control booth is also a secondary barrier, toward which the primary beam must never be directed. 68. (D) Selection o exposure actors has a signi cant impact on patient dose. Remember that milliampere-seconds (mAs) are used to regulate the quantity o radiation delivered to the patient and kilovolts peak (kVp) determines the penetrability o the x-ray beam. As kilovoltage is increased, more high-energy photons are produced, and the overall average energy o the beam is increased. An increase in milliampere-seconds increases the number o photons produced at the target, but milliampere-seconds are unrelated to photon energy. Generally speaking, then, in an e ort to keep radiation dose to a minimum, it makes sense to use the lowest mAs setting and the highest kVp setting that will produce the desired radiographic results. An added bene t is that at high kilovolts peak and low milliampere-second values, the heat delivered to the x-ray tube is lower, and tube li e is extended. In this example, (A) = 75 mAs, (B) = 37.5 mAs, (C) = 36 mAs, and (D) = 18 mAs. Decreasing the milliampere-seconds and increasing the kilovolts peak appropriately is the most e ective combination or reducing patient dose. 69. (B) Because the primary x-ray beam has a polyenergetic (heterogeneous) nature, the entrance or skin dose is signi cantly greater than the exit dose. T is principle may be employed in radiation protection by placing particularly radiosensitive organs away rom the primary beam. o place the gonads urther rom the primary beam and reduce gonadal dose, abdominal radiography should be per ormed in the posteroanterior (PA) position whenever possible. Dose to the lens is decreased signi cantly when skull radiographs are per ormed in the PA position.

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70. (C) According to the NCRP, the annual occupational whole-body dose-equivalent limit is 50 mSv (5 rem or 5,000 mrem). T e annual occupational whole-body dose-equivalent limit or students under the age o 18 years is 1 mSv (100 mrem or 0.1 rem). T e annual occupational dose-equivalent limit or the lens o eye is 150 mSv (15 rem). T e annual occupational dose-equivalent limit or the thyroid, skin, and extremities is 500 mSv (50 rem). T e total gestational dose-equivalent limit or embryo/ etus o a pregnant radiographer is 5 mSv (500 mrem), not to exceed 0.5 mSv in 1 month. 71. (A) LE increases with the ionizing potential o the radiation; or example, alpha particles are more ionizing than x-radiation; there ore, they have a higher LE . As ionizations and LE increase, there is greater possibility o an e ect on living tissue; there ore, the RBE increases. T e RBE (sometimes called the quality actor) o diagnostic x-rays is 1, the RBE o ast neutrons is 10, and the RBE o 5-MeV alpha particles is 20. 72. (B) Dose–response curves are used to illustrate the relationship between exposure to ionizing radiation and possible resultant biologic responses. Figure 3-2 illustrates three dose–response curves. Curve A begins at zero, indicating that there is no sa e dose, that is, no threshold. Even one x-ray photon theoretically can cause a response. It is a straight (linear) line, indicating that response is proportional to dose. T at is, as dose increases, response increases. Curve B is another linear curve, but this one illustrates a situation in which a particular dose o radiation must be received be ore the response will occur. T at is, there is a threshold dose, and this is a linear threshold curve. Curve C is another threshold curve, but this curve is nonlinear. It illustrates that once the minimum dose is received, a response occurs slowly initially and then increases sharply as exposure increases. 73. (B) In the past ew decades, ICRP and NCRP studies have indicated that radiation-induced cancer risks are greater than radiation-induced genetic risks—contrary to previous thought. heir philosophy then grew to be concerned with the probability o radiation-induced cancer mortality in the occupational radiation industry in comparison with annual accidental mortality in “sa e” (radiation- ree) industries. he NCRP

reexamined its 1987 recommendations, and in NCRP Report No. 116, it reiterates its annual e ective occupational dose limit as 50 mSv (5 rem). 74. (A) As an x-ray source moves away rom a detector, the x-ray intensity (quantity) decreases. Conversely, as the source o x-rays moves closer to the detector, the intensity increases. T is is a predictable relationship that may be calculated using the inverse-square law, which states that the intensity (exposure rate) o radiation at a given distance rom a point source is inversely proportional to the square o the distance. For example, i the distance rom an x-ray source were doubled, the intensity o x-rays at the detector would be one- ourth its original value. T is relationship is represented by the ormula: 2 I1 D 2 = 2 I2 D1

75. (A) Aluminum lters are used to decrease patient skin dose by absorbing the low-energy photons (there ore, decreased milliroentgen output) that do not contribute to the image but do contribute to patient skin dose. HVL is de ned as that thickness o any absorber that will decrease the intensity o a particular beam to one-hal its original value. As ltration o an x-ray beam is increased, the overall average energy o the resulting beam is greater (because the low-energy photons have been removed) and, there ore, the HVL thickness required would be greater. 76. (A) X-ray photons emerging rom the ocal spot comprise a heterogeneous primary beam. T ere are many low-energy x-rays that, i not removed, would contribute signi cantly to patient skin dose. T ese low-energy photons are too weak to penetrate the patient and expose the IR; they simply penetrate a small thickness o tissue be ore being absorbed. Filters, usually made o aluminum, are used in radiography to reduce patient dose by removing this low-energy radiation (i.e., decreased beam intensity) and resulting in an x-ray beam o higher average energy. otal ltration is composed o inherent ltration plus added ltration. X-ray photons scatter only a er they have interacted with the absorber/patient; scatter is unrelated to ltration.

Answers: 70–85

77. (B) Use actor describes the percentage o time that the primary beam is directed toward a particular wall. T e use actor is one o the actors considered in determining protective barrier thickness. Another is workload, which is determined by the number o x-ray exposures made per week. Occupancy actor is a re ection o who occupies particular areas (radiation workers or nonradiation workers) and is another actor used in determining radiation barrier thickness. 78. (D) Ionization is the undamental principle o operation o both the lm badge and the pocket dosimeter. In the lm badge, the lm’s silver halide emulsion is ionized by x-ray photons. T e pocket dosimeter contains an ionization chamber, and the number o ionizations taking place may be equated to the exposure dose. LDs contain lithium uoride crystals that undergo characteristic changes on irradiation. When the crystals are subsequently heated, they emit a quantity o visible (thermo) luminescence/light in proportion to the amount o radiation absorbed. OSL dosimeters contain aluminum oxide crystals that also undergo characteristic changes on irradiation. When the Al2 O3 crystals are stimulated by a laser, they emit (optically stimulated) luminescence/light in proportion to the amount o radiation absorbed. 79. (B) As the size o the irradiated eld decreases, scattered radiation production and patient hazard decrease. I the amount o scattered radiation decreases, then radiographic contrast is higher (shorter scale). 80. (D) Source-to-image-receptor distance (SID) has a signi cant impact on x-ray beam intensity (other terms we could use are exposure rate and dose). As the distance between the x-ray tube and IR increases, exposure rate/intensity/dose (and, there ore, radiographic density) decreases according to the inversesquare law. According to the inverse-square law, the exposure rate is inversely proportional to the square o the distance; that is, i the SID is doubled, the resulting beam intensity will be one- ourth the original intensity; i the SID is cut in hal , the resulting beam intensity will be 4 times the original intensity. 81. (A) Occupationally exposed individuals generally receive small amount o low-energy radiation over a long period o time. T ese individuals, there ore,

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are concerned with the potential long-term e ects o radiation, such as carcinogenesis (including leukemia) and cataractogenesis. However, i a large amount o radiation is delivered to the whole body at one time, the short-term early somatic e ects must be considered. I the whole body receives 600 rad at one time, acute radiation syndrome is likely to occur. Early signs o acute radiation syndrome include nausea, vomiting, diarrhea, atigue, and leukopenia (decreased white blood cells count); these occur in the rst (prodromal) stage o acute radiation syndrome. 82. (D) An approximate ESE can be determined using the illustrated nomogram. First, mark 2.5 mm Al on the x (horizontal) axis. Next, mark where a line drawn up rom that point intersects the 70-kVp line. Draw a line straight across to the y (vertical) axis; this should approximately reach the 4.8 mR/ mAs point. Because 60 mAs was used or the exposure, the approximate ESE is 288 mR (60 × 4.8). 83. (C) Roentgen was the traditional unit o exposure; it is still o en used to express the quantity o ionizations in air. Rad is an acronym or radiation absorbed dose; it has been used measure the energy deposited in any material and has been replaced by the gray (Gy). Rem is an acronym or radiationequivalent man; it includes the RBE speci c to the tissue irradiated and, there ore, is a valid unit o measurement or the dose to biologic material. Personal dosimeters still use the rem to report occupational exposure, however the unit has been largely replaced by the Sievert. 84. (C) Quality control involves testing and maintenance o equipment, while quality assurance involves direct patient-related actors. Sensitometry and densitometry are used in evaluation o an x-ray lm processor; they are just one portion o a complete QC program. Modulation trans er unction (M F) is used to express spatial resolution— another component o the QC program. A complete QC program includes testing, monitoring, and maintenance o all equipment components o the imaging system— ltration (HVL), collimation, ocal spot, x-ray timers, intensi ying screens, beam alignment, and so on. 85. (C) All uoroscopic equipment has protective devices and protocols to protect the patient and user.

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Fluoroscopic equipment must provide at least 12 in (30 cm) and pre erably 15 in (38 cm) between the x-ray source ( ocal spot) and the x-ray tabletop (patient), according to NCRP Report No. 102. T e tabletop intensity o the uoroscopic beam must not exceed 10 R/min or 2.1 R/min/mA. With under-table uoroscopic tubes, a Bucky slot closer/cover having at least the equivalent o 0.25 mm Pb must be available to attenuate scattered radiation coming rom the patient, posing a radiation hazard to the uoroscopist and radiographer. Fluoroscopic milliamperes must not exceed 5 mA. Because the image intensi er unctions as a primary barrier, it must have a lead equivalent o at least 2.0 mm. A cumulative timing device must be available to signal the uoroscopist when a maximum o 5 minutes o uoroscopy time has elapsed. Because occupational exposure to scattered radiation is o considerable importance in uoroscopy, a protective curtain/ drape o at least 0.25-mm Pb equivalent must be placed between the patient and uoroscopist. 86. (D) T e pocket dosimeter, or pocket ionization chamber, resembles a penlight. Within the dosimeter is a thimble ionization chamber. In the presence o ionizing radiation, a particular quantity o air will be ionized and cause the ber indicator to register radiation quantity in milliroentgen (mR). T e sel -reading type may be “read” by holding the dosimeter up to the light and, looking through the eyepiece, observing the ber indicator, which indicates a quantity o 0 to 200 mR. Although it provides an immediate reading while other personnel monitors require “processing,” the disadvantage o the pocket dosimeter is that it does not provide a permanent legal record o exposure. 87. (B) Kilovoltage (kV) and the HVL e ect a change in both the quantity and the quality o the primary beam. T e principal qualitative actor o the primary beam is kilovoltage, but an increase in kilovoltage will also increase the number o photons produced at the target. HVL, de ned as the amount o material necessary to decrease the intensity o the beam to one-hal , there ore changes both beam quality and beam quantity. Milliamperage is directly proportional to x-ray intensity (i.e., quantity/dose rate) but is unrelated to the quality o the beam. 88. (B) Gonadal shielding should be used whenever appropriate and possible during radiographic and

uoroscopic examinations. Flat contact shields are use ul or simple recumbent studies, but when the examination necessitates obtaining oblique, lateral, or erect projections, at contact shields are easily displaced and become less ef cient. Shaped contact (contour) shields are best because they enclose the male reproductive organs (principally the anterior and lateral portions) and remain in position or oblique, lateral, and erect projections. Shadow shields that attach to the tube head are particularly use ul or surgical sterile elds. 89. (B) Isotopes are atoms o the same element (the same atomic number or number o protons) but a di erent mass number. T ey di er, there ore, in their number o neutrons. Atoms having the same mass number but di erent atomic number are isobars. Atoms having the same neutron number but di erent atomic number are isotones. Atoms with the same atomic number and mass number are isomers. 90. (D) T e patient is the most important radiation scatterer during both radiography and uoroscopy. In general, at 1 m rom the patient, the intensity is reduced by a actor o 1,000 to about 0.1% o the original intensity. Successive scatterings can reduce the intensity to unimportant levels. Calculate that 0.1% o 25 mrad is 0.025 mrad. 91. (C) T e likelihood o radiation e ects to occupationally exposed individuals whose dose is kept below the recommended limits is very remote. Exposure to ionizing radiation always carries some risk, but studies have indicated that the risk is a very small one i established guidelines are ollowed. Potential hazards must be understood and proper precautions taken. 92. (B) T e amount o scattered radiation produced depends rst on the kilovoltage (beam quality) selected; the higher the kilovolts peak, the more scattered radiation is produced. T e size o the irradiated eld also has a great deal to do with the amount o scattered radiation produced; the larger the eld size, the greater is the amount o scattered radiation. T ickness and condition o tissue also are important considerations; the thicker and/or more dense the tissue, the more scatter is produced. I the condition o the tissue is such that pathology makes it more dif cult to penetrate, more scattered

Answers: 86–99

radiation will be produced. Grid ratio has no e ect on the amount o scattered radiation produced but does signi cantly impact the amount o scattered radiation reaching the IR. 93. (C) Lead and distance are the two most important ways to protect rom radiation exposure. Fluoroscopy can be particularly hazardous because the source-to-skin distance (SSD) is so much shorter than in overhead radiography. T ere ore, it has been established that xed (stationary) and mobile uoroscopic equipment must provide at least 12 in (30 cm) o SSD or protection o the patient. 94. (A) Automatic exposure control (AEC) devices are used in today’s equipment and serve to produce consistent and comparable radiographic results. In one type o AEC, there is an ionization chamber just beneath the tabletop above the IR. T e part to be examined is centered on it (the sensor) and radiographed. When a predetermined quantity o ionization has occurred (equal to the correct density), the exposure terminates automatically. In the other type o AEC, the phototimer/photomultiplier, a small uorescent screen is positioned beneath the IR. When remnant radiation emerging rom the patient exposes the IR and exits the IR, the uorescent screen emits light. Once a predetermined amount o uorescent light is “seen” by the photocell sensor, the exposure is terminated. A scintillation camera is used in nuclear medicine. A photocathode is an integral part o the image intensi cation system. 95. (B) According to the NCRP, the annual occupational whole-body dose-equivalent limit is 50 mSv (5 rem or 5,000 mrem). T e annual occupational whole-body dose-equivalent limit or students under the age o 18 years is 1 mSv (100 mrem or 0.1 rem). T e annual occupational dose-equivalent limit or the lens o eye is 150 mSv (15 rem). T e annual occupational dose-equivalent limit or the thyroid, skin, and extremities is 500 mSv (50 rem). T e total gestational dose-equivalent limit or embryo/ etus o a pregnant radiographer is 5 mSv (500 mrem), not to exceed 0.5 mSv in 1 month. 96. (B) It is our ethical responsibility to minimize radiation exposure to ourselves and our patients, particularly during early pregnancy. One way to do this is to inquire about the possibility o our emale

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patients being pregnant or or the date o their last menstrual period (to determine the possibility o irradiating a newly ertilized ovum). T e sa est time or a woman o childbearing age to have elective radiographic examinations is during the rst 10 days ollowing the onset o menstruation. 97. (A) Figure 3-4 illustrates three dose–response curves. Dose–response curves are used to illustrate the relationship between exposure to ionizing radiation and possible resultant biologic responses. Curve A begins at zero, indicating that there is no sa e dose, that is, no threshold. Even one x-ray photon theoretically can cause a response. It is a straight (linear) line, indicating that response is proportional to dose; as dose increases, response increases. Radiation-induced cancer, leukemia, and genetic e ects ollow a linear nonthreshold dose–response relationship. Curve B is another linear curve (response is proportional to dose), but this one illustrates that a particular dose o radiation must be received be ore a response will occur. T at is, there is a threshold dose; this is called a linear threshold curve. Curve C is another threshold curve, but this curve is nonlinear. It illustrates that once the minimum dose is received, a response occurs slowly initially and then increases sharply as exposure increases. T is threshold, nonlinear (sigmoid) dose–response curve, illustrates the e ect to skin rom exposure to high levels o ionizing radiation. 98. (A) LE expresses the rate at which photon or particulate energy is trans erred to (absorbed by) biologic material (through ionization processes); it depends on the type o radiation and the characteristics o the absorber. RBE describes the degree o response or amount o biologic change one can expect o the irradiated material. As the amount o trans erred energy (LE ) increases ( rom interactions occurring between radiation and biologic material), the amount o biologic e ect/damage will also increase. 99. (A) T e shorter the SID, the greater is the skin dose. T at is why there are speci c SSD restrictions in uoroscopy. High-kilovolt peak produces more penetrating photons, thereby decreasing skin dose. Filtration is used to remove the low-energy photons rom the primary beam, which contribute to skin dose.

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100. (A) Radiation e ects that appear days or weeks ollowing exposure (early e ects) are in response to relatively high radiation doses. T ese should never occur in diagnostic radiology today; they occur only in response to doses much greater than those used in diagnostic radiology. One o the e ects that may be noted in such a circumstance is the hematologic e ect—reduced numbers o white blood cells, red blood cells, and platelets in the circulating blood. Immediate local tissue e ects can include e ects on the gonads (i.e., temporary in ertility) and on the skin (e.g., epilation and erythema). Acute radiation lethality, or radiation death, occurs a er an acute exposure and results in death in weeks or days. Radiation-induced malignancy, leukemia, and genetic e ects are late e ects (or stochastic/probabilistic e ects) o radiation exposure. T ese can occur years a er survival o an acute radiation dose or a er exposure to low levels o radiation over a long period o time. Radiation workers need to be especially aware o the late e ects o radiation because their exposure to radiation is usually low level over a long period o time. Occupational radiation protection guidelines, there ore, are based on late e ects o radiation according to a linear, nonthreshold dose–response curve. 101. (C) LE increases with the ionizing potential o the radiation; or example, alpha particles are more ionizing than x-radiation, and, there ore, they have a higher LE . As ionizations and LE increase, there is greater possibility o an e ect on living tissue; there ore, the RBE increases. T e RBE (sometimes called quality actor [QF]) o diagnostic x-rays is 1, the RBE o ast neutrons is 10, the RBE o 5-MeV alpha particles is 20, and the RBE o 10-MeV protons is 5.0. 102. (B) A quick survey o the distractors reveals that option (A) will increase exposure dose and thus is eliminated as a possible correct answer. Options (B), (C), and (D) will serve to reduce radiation exposure because in each case either time is decreased or distance is increased. It remains to be seen, then, which is the more e ective. Using the inverse-square law o radiation, at a distance o 8 , the individual will receive 12.5 mR in 2 minutes (double distance rom source = one- ourth the original intensity). At 5 , the individual will receive 16 mR in 1 minute:

2 50( I1 ) 25 D 2 = x ( I 2 ) 16 D12

( )

25x = 800 T us, x = 32 mR in 2 minutes and, there ore, 16 mR in 1 minute at 5 . At 6 , the individual will receive 22.2 mR in 2 minutes: 2 50( I1 ) 36 D 2 = x ( I 2 ) 16 D12

( )

36x = 800 T us, x = 22.22 mR in 2 minutes at 6 . T ere ore, the most e ective option is (B), 12.5 mR in 2 minutes at 8 f . 103. (B) Di erent types o monitoring devices are available or the occupationally exposed. T e lm badge has photographic lm; the pocket dosimeter contains an ionization chamber; LDs use lithium uoride crystals. OSL dosimeters are personnel radiation monitors that use aluminum oxide crystals. T ese crystals, once exposed to ionizing radiation and then subjected to a laser, give o luminescence proportional to the amount o radiation received. 104. (D) Fractionation and protraction in uence the e ect o radiation on tissue. Larger quantities, o course, increase tissue e ect. T e energy (i.e., quality and penetration) o the radiation determines whether the e ects will be super cial (erythema) or deep (organ dose). Certain tissues (such as blood- orming organs and the gonads) are more radiosensitive than others (such as muscle and nerve). I the dose is delivered in portions ( ractionation) and/or delivered over a length o time (protraction), the less the tissue e ects. 105. (A) In the photoelectric e ect, a relatively low-energy incident photon uses all its energy to eject an innershell electron, leaving a vacancy. An electron rom the next shell will drop to ll the vacancy, and a characteristic ray is given up in the transition. T is type o interaction is more harm ul to the patient because all the photon energy is trans erred to tissue. 106. (A) Filters are used in radiography to remove so (low-energy) radiation that contributes only to patient dose. T e lters usually are made o aluminum. Equipment operating above 70 kVp must have total iltration o 2.5-mm Al equivalent (inherent + added).

Answers: 100–115

107. (C) T e use o a grid requires an increase in milliampere-seconds and, there ore, patient dose; the higher the grid ratio, the greater is the increase in milliampere-seconds required. Collimation (beam restriction) restricts the amount o tissue being irradiated and, there ore, reduces patient dose. High kilovoltage reduces the amount o radiation absorbed by the patient’s tissues (recall the photoelectric e ect), and low milliampere-seconds reduces the quantity o radiation delivered to the patient. T e higher the speed o the imaging system (e.g., lm–screen combination), the less are the required milliampere-seconds. 108. (D) Bremsstrahlung (or Brems) radiation is one o the two kinds o x-rays produced at the tungsten target o the x-ray tube during interaction between high-speed electrons coming rom the lament and the anodes’ tungsten atoms. T e incident highspeed electron, passing through a tungsten atom, is attracted by the positively charged nucleus and, there ore, is de ected rom its course, with a resulting loss o energy. T is energy is given up in the orm o an x-ray photon. 109. (D) Dose–response curves are used to illustrate the relationship between exposure to ionizing radiation and possible resultant biologic responses. T e genetic e ects o radiation and some somatic e ects, such as leukemia, are plotted on a linear dose–response curve. T e linear dose–response curve has no threshold; that is, there is no dose below which radiation is absolutely sa e. T e nonlinear/ sigmoidal dose–response curve has a threshold and is thought to be generally correct or most somatic e ects—such as skin erythema, epilation, hematologic depression, and radiation lethality (death). 110. (B) Roentgen was the traditional unit o exposure and it is still o en used to express the quantity o ionizations in air. Rad is an acronym or radiation absorbed dose; it has been used measure the energy deposited in any material and has been replaced by the gray (Gy). Rem is an acronym or radiation-equivalent man; it includes the RBE speci c to the tissue irradiated and, there ore, is a valid unit o measurement or the dose to biologic material. Personal dosimeters still use the rem to report occupational exposure, however the unit has been largely replaced by the Sievert.

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111. (B) T e lters (usually aluminum and copper) serve to help measure radiation quality (i.e., energy). Only the most energetic radiation will penetrate the copper; radiation o lower levels o energy will penetrate the aluminum, and the lowest energy radiation will pass readily through the un ltered area. T us, radiation o di erent energy levels can be recorded, measured, and reported. 112. (B) An HVL may be de ned as the amount and thickness o absorber necessary to reduce the radiation intensity to hal its original value. T us, the rst HVL would reduce the intensity to 50% o its original value, the second to 25%, the third to 12.5%, and the ourth to 6.25% o its original value. 113. (D) All the actors listed in uence the e ect o radiation on tissue. Larger quantities, o course, increase radiation’s e ect on tissue. T e energy (i.e., quality and penetration) o the radiation determines whether the e ects will be super cial (erythema) or deep (organ dose). Certain tissues (such as blood- orming organs and the gonads) are more radiosensitive than others (such as muscle and nerve). T e length o time over which the exposure is spread ( ractionation) is important; the longer the period o time, the less are the tissue e ects. 114. (B) Radiographic and uoroscopic equipment is designed to help decrease the exposure dose to patient and operator. One o the design eatures is the exposure cord. Exposure cords on xed equipment must be short enough to prevent the exposure rom being made outside the control booth. Exposure cords on mobile equipment must be long enough to permit the operator to stand at least 6 rom the x-ray tube. 115. (C) Radiation protection guidelines have established that primary radiation barriers must be 7 high. Primary radiation barriers are walls toward which the primary beam may be directed. T ese walls usually contain 1.5 mm (1/16 inch) o lead, but this can vary depending on use actor, etc. Secondary radiation barriers include that portion o the walls above 7 in height; this area requires only 1/32 inch o lead. T e control booth is also a secondary barrier, toward which the primary beam must never be directed.

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116. (B) Whole-body dose is calculated to include all the especially radiosensitive organs. T e gonads and the blood- orming organs are particularly radiosensitive. Some body parts, such as the skin and extremities, have a higher annual dose limit. 117. (A) Exposure dose to patients can be expressed as entrance skin exposure (ESE), sometimes re erred to as skin entrance exposure (SEE). Exposure can also be expressed in terms o organ dose. Organ doses to the gonads, bone marrow, breast, thyroid, lens, and lung can be determined. Patient position and beam restriction o en make a signi cant di erence in patient dose. Examinations per ormed PA, rather than AP, o en decrease exposure to sensitive organs. T is is so because the lower-energy x-ray photons will be absorbed by the anatomic structures closer to the x-ray source, and the higher-energy photons will penetrate and exit the part (penetrating the sensitive part rather than being absorbed by it). PA abdomen radiographs deliver less quantity dose to the reproductive organs than do AP abdomen radiographs. An AP skull head and neck projection (80 kVp) delivers about 0.9 mGy (90 mrad) to the thyroid, whereas a PA skull head and neck (80 kVp) radiograph projection deliver abouts 0.8 mGy (8 mrad); a PA esophagus (110 kVp) image delivers 0.09 mGy (9 mrad), and the PA chest (120 kVp) delivers about 0.008 mGy (0.8 mrad). 118. (C) Ionization is the undamental principle o operation o both the lm badge and the pocket dosimeter. In the lm badge, the lm’s silver halide emulsion is ionized by x-ray photons. T e pocket dosimeter contains an ionization chamber, and the number o ionizations taking place may be equated to exposure dose; it is accurate, but it is used principally to detect larger amounts o radiation exposure. T e LD can measure exposures as low as 5 mrem, whereas lm badges cannot express exposure less than 10 mrem. LDs contain lithium uoride crystals that undergo characteristic changes on irradiation. When the crystals are subsequently heated, they emit a quantity o visible (thermo) luminescence/light in proportion to the amount o radiation absorbed. T e relatively new OSL dosimeters contain aluminum oxide crystals that also undergo characteristic changes on irradiation. When the Al2O3 crystals are stimulated by a laser, they emit (optically stimulated) luminescence/

light in proportion to the amount o radiation absorbed. OSL dosimeters can measure exposures as low as 1 mrem. 119. (D) Irradiation damage is a result o either the e ects o irradiation on water (radiolysis) or its e ects on macromolecules. E ects on macromolecules include cleaved chromosomes, cross-linking, and mutations. Cleaved/broken chromosome is the result o a double-strand break on the same DNA “rung”. Cross-linking is incorrect joining o broken DNA ragments. A mutation is the result o damage/alteration o nitrogenous base sequence as a result o irradiation. Because 80% o the body is made up o water, radiolysis o water is the predominant radiation interaction in the body. 120. (C) T e greatest e ect–response rom irradiation is brought about by a large dose o radiation to the whole body delivered all at one time. Whole-body radiation can depress many body unctions. With a ractionated dose, the e ects would be less severe because the body would have an opportunity to repair between doses. 121. (B) Lead aprons are worn by occupationally exposed individuals during uoroscopic procedures. Lead aprons are available with various lead equivalents; 0.25, 0.5, and 1.0 mm o lead are the most common. T e 1.0-mm lead equivalent apron will provide close to 100% protection at most kilovoltage levels, but it is rarely used because it weighs anywhere rom 12 to 24 lb. A 0.25-mm lead equivalent apron will attenuate about 97% o a 50-kVp x-ray beam, 66% o a 75-kVp beam, and 51% o a 100-kVp beam. A 0.5-mm apron will attenuate about 99% o a 50-kVp beam, 88% o a 75-kVp beam, and 75% o a 100-kVp beam. 122. (C) Di erent types o monitoring devices are available or the occupationally exposed, and anyone who might receive more than one-tenth the annual dose limit must be monitored. Ionization is the undamental principle o operation o both the lm badge and the pocket dosimeter. In the lm badge, the lm’s silver halide emulsion is ionized by x-ray photons. T e pocket dosimeter contains an ionization chamber (containing air), and the number o ions ormed (o either sign) is equated to exposure dose. LDs are radiation monitors that use lithium uoride crystals. Once exposed to

Answers: 116–128

ionizing radiation and then heated, these crystals give o light proportional to the amount o radiation received. OSL dosimeters are radiation monitors that use aluminum oxide crystals. T ese crystals, once exposed to ionizing radiation and then subjected to a laser, give o luminescence proportional to the amount o radiation received. 123. (B) T e principal interactions that occur between x-ray photons and body tissues in the diagnostic x-ray range, the photoelectric e ect and Compton scatter, are ionization processes producing photoelectrons and recoil electrons that traverse tissue and subsequently ionize molecules. In the illustrated Compton scatter, a airly high-energy x-ray photon ejects an outer-shell electron. Although the x-ray photon is de ected with reduced energy (modi ed scatter), it retains most o its original energy and exits the body as an energetic scattered photon. Because the scattered photon exits the body, it does not pose a radiation hazard to the patient. It can, however, contribute to image og and pose a radiation hazard to personnel (as in uoroscopic procedures). In the photoelectric e ect, a low-energy x-ray photon uses all its energy to eject an inner-shell electron, leaving an orbital vacancy. An electron rom the shell above lls the vacancy and in so doing gives up energy in the orm o a characteristic ray. T e photoelectric e ect is more likely to occur in absorbers having high atomic number and contributes signi cantly to patient dose because all the photon energy is absorbed by the patient. Coherent (unmodi ed) scatter does not involve ionization. 124. (A) issue is most sensitive to radiation when it is oxygenated and least sensitive when it is devoid o oxygen. Anoxic re ers to tissue without oxygen; hypoxic re ers to tissue with little oxygen. Anoxic and hypoxic tumors typically are avascular (with little or no blood supply) and, there ore, more radioresistant. 125. (B) Bergonié and ribondeau theorized in 1906 that all precursor cells are particularly radiosensitive (e.g., stem cells ound in bone marrow). T ere are several types o stem cells in bone marrow, and the di erent types di er in degree o radiosensitivity. O these, red blood cell precursors, or erythroblasts, are the most radiosensitive. White blood cell precursors, or myelocytes, ollow. Platelet

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precursor cells, or megakaryocytes, are the least radiosensitive. Myocytes are mature muscle cells that are airly radioresistant. 126. (D) T e pregnant radiographer should declare her pregnancy to her supervisor; at that time, her radiation exposure history can be reviewed and appropriate assignments made. Special arrangements are required or occupational monitoring o the pregnant radiographer. T e pregnant radiographer will wear two dosimeters—one in its usual place at the collar and the other, a baby/ etal dosimeter, worn over the abdomen and under the lead apron during uoroscopy. T e baby/ etal dosimeter must be identi ed as such and always must be worn in the same place. Care must be taken not to mix the positions o the two dosimeters. T e dosimeters are read monthly as usual. 127. (D) Irradiation o cellular DNA has the potential to produce a number o e ects that can have an impact on the structure and/or unction o the cell. T e cell’s mitotic potential can be delayed or completely stopped. Most chromosome breakage/damage is an indirect consequence o irradiation. I the damage happens to the DNA o a germ cell, the radiation response may not occur until one or more generations later. 128. (A) In the photoelectric e ect, a relatively lowenergy photon uses all its energy to eject an innershell electron, leaving a vacancy. An electron rom the shell above drops down to ll the vacancy and in so doing emits a characteristic ray. T is type o interaction is most harm ul to the patient because all the photon energy is trans erred to tissue. In Compton scatter, a high-energy incident photon uses some o its energy to eject an outer-shell electron. In so doing, the incident photon is de ected with reduced energy but usually retains most o its energy and exits the body as an energetic scattered ray. T e scattered radiation will either contribute to image og or pose a radiation hazard to personnel depending on its direction o exit. In classic scatter, a low-energy photon interacts with an atom but causes no ionization; the incident photon disappears in the atom and then reappears immediately and is released as a photon o identical energy but with changed direction. T ompson scatter is another name or classic scatter.

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129. (C) Dose–response curves are used to illustrate the relationship between exposure to ionizing radiation and possible resultant biologic responses. Figure 3-6 shows a linear threshold dose–response curve. Its linear aspect indicates that the response/ e ect is related directly to the dose received; that is, as the dose increases, the response increases. T e act that this is a threshold curve indicates that a particular dose is required be ore any response/ e ect will occur. 130. (C) Early somatic e ects are mani ested within minutes, hours, days, or weeks o irradiation and occur only ollowing a very large dose o ionizing radiation. It must be emphasized that doses received rom diagnostic radiologic procedures are not suf cient to produce these early e ects. An exceedingly high dose o radiation delivered to the whole body in a short period o time is required to produce early somatic e ects. T ese whole-body responses are grouped into three categories— re ecting the system(s) a ected and the resulting symptoms: hematologic, gastrointestinal, and central nervous system. 131. (A) Characteristic radiation is one o two kinds o x-rays produced at the tungsten target o the x-ray tube. T e incident, or incoming, high-speed electron ejects a K-shell tungsten electron. T is leaves a hole in the K shell, and an L-shell electron drops down to ll the K vacancy. Because L electrons are at a higher-energy level than K-shell electrons, the L-shell electron gives up the di erence in binding energy in the orm o a photon, a characteristic x-ray (characteristic o the K shell). 132. (A) T e genetically signi cant dose (GSD) illustrates that large exposures to a ew people are cause or little concern when diluted by the total population. On the other hand, we all share the burden o that radiation received by the total population, especially as the use o medical radiation increases, so each individual’s share o the total exposure increases. 133. (A) T e relationship between x-ray intensity and distance rom the source is expressed by the inverse-square law o radiation. T e ormula is 2 I1 D 2 = 2 I2 D1

Substituting known values: 50 25 = x 9 25x = 450 T us, x = 18 mR/h (60 minutes) and, there ore, 6 mR in 20 minutes. Distance has a pro ound e ect on dose received and, there ore, is one o the cardinal rules o radiation protection. As distance rom the source increases, dose received decreases. 134. (A) Every radiographic examination involves an ESE, which can be determined airly easily. It also involves a gonadal dose and a marrow dose, which, i needed, can be calculated by the radiation physicist. I the ESE o a particular examination were calculated to determine the equivalent whole-body dose, this would be termed the e ective dose. For example, the ESE o a PA chest radiograph is approximately 70 mrem, whereas the e ective dose is 10 mrem. T e e ective (whole body) dose is much less because much o the body is not included in the primary beam. 135. (C) Somatic e ects are those induced in the irradiated body. Genetic e ects o ionizing radiation are those that may not appear or many years (generations) ollowing exposure. Formation o cataracts or cancer (such as leukemia) and embryologic damage are all possible long-term somatic e ects o radiation exposure. A ourth is li e-span shortening. Blood changes are generally early e ects o exposure to large quantities o ionizing radiation. 136. (B) Occupationally exposed individuals are required to use devices to record and document the radiation they receive over a given period o time, traditionally 1 month. T e most commonly used personal dosimeters are the OSL dosimeter, the LD, and the lm badge. T ese devices are worn only or documentation o occupational exposure, not or any medical or dental x-rays received as a patient. LDs are radiation monitors that use lithium uoride crystals. Once exposed to ionizing radiation and then heated, these crystals give o light proportional to the amount o radiation received. OSL dosimeters are radiation monitors that use aluminum oxide crystals. T ese crystals, once exposed to ionizing radiation and then subjected to a laser, give o luminescence proportional to the amount o radiation received. T e pocket dosimeter contains an ionization

Answers: 129–143

chamber (containing air), and the number o ions ormed (o either sign) is equated to exposure dose. 137. (D) A measure 1,400 mrad is equal to 1.4 rad. I 1.4 rad were delivered in 7 minutes, then the dose rate would be 0.2 rad/min: 1.4 rad x rad = 7 min 1 min 7 x = 1.4 x = 0.2 Rad min 138. (A) T e tissue weighting actor (Wt) represents the relative tissue radiosensitivity o irradiated material (e.g., muscle vs. intestinal epithelium vs. bone). T e radiation weighting actor (Wr) is a number assigned to di erent types o ionizing radiations in order to better determine their e ect on tissue (e.g., x-ray vs. alpha particles). T e Wr o di erent ionizing radiations depends on the LE o that particular radiation. T e ollowing ormula is used to determine e ective dose ...e ective dose (E D): E ective dose (E D) = radiation weighting actor Wr × tissue weighting actor Wt × absorbed dose 139. (B) T e principal interactions that occur between x-ray photons and body tissues in the diagnostic x-ray range, the photoelectric e ect and Compton scatter, are ionization processes producing photoelectrons and recoil electrons that traverse tissue and subsequently ionize molecules. T ese interactions occur randomly but can lead to molecular damage in the orm o impaired unction or cell death. T e target theory speci es that DNA molecules are the targets o greatest importance and sensitivity; that is, DNA is the key sensitive molecule. However, since the body is 65% to 80% water, most interactions between ionizing radiation and body cells will involve radiolysis o water rather than direct interaction with DNA. T e two major types o e ects that occur are the direct e ect and the indirect e ect. T e direct e ect usually occurs with high-LE radiations and when ionization occurs at the DNA molecule itsel . T e indirect e ect, which occurs most requently, happens when ionization takes place away rom the DNA molecule in cellular water. However, the energy rom the interaction can be trans erred to the molecule via a ree radical ( ormed by radiolysis o cellular water).

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Possible damage to the DNA molecule is diverse. A single main-chain/side-rail scission (break) on the DNA molecule is repairable. A double main-chain/ side-rail scission may be repaired with dif culty or may result in cell death. A double main-chain/siderail scission on the same rung o the DNA ladder results in irreparable damage or cell death. Faulty repair o main-chain breakage can result in cross-linking. Damage to the nitrogenous bases, that is, damage to the base itsel or to the rungs connecting the main chains, can result in alteration o base sequences, causing a molecular lesion/point mutation. Any subsequent divisions result in daughter cells with incorrect genetic in ormation. 140. (C) T e patient, as the rst scatterer, is the most important scatterer. At 1 m rom the patient, the intensity o the scattered beam is 0.1% o the intensity o the primary beam. Compton scatter emerging rom the patient is almost as energetic as the primary beam entering the patient. 141. (D) A LD is a sensitive and accurate device used in radiation dosimetry. It may be used as a personal dosimeter or to measure patient dose during radiographic examinations and therapeutic procedures. T e LD uses a thermoluminescent phosphor, usually lithium uoride. When used as a personal monitor, the LD is worn or 1 month. During this time, it stores in ormation regarding the radiation to which it has been exposed. It is then returned to the commercial supplier. In the laboratory, the phosphors are heated. T ey respond by emitting a particular quantity o light (not heat) that is in proportion to the quantity o radiation delivered to it. A er they are cleared o stored in ormation, they are returned or reuse. 142. (A) Because the established dose-limit ormula guideline is used or occupationally exposed persons 18 years o age and older, guidelines had to be established to cover the event that a student entered the clinical component o a radiography educational program prior to age 18. T e guideline states that the occupational dose limit or students under 18 years o age is 0.1 rem (100 mrem or 1 mSv) in any given year. 143. (A) Medical imaging includes diagnostic x-ray, computed tomography, interventional procedures, diagnostic sonography, magnetic resonance imaging, nuclear medicine, etc. Some orms o medical

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imaging utilize ionizing radiation, others do not. Diagnostic x-ray, uoroscopy and interventional procedures, computed tomography (C ), nuclear medicine, and positron emission tomography (PE ) all utilize ionizing radiation. Sonography utilizes sound waves; magnetic resonance imaging (MRI) utilizes magnetic elds. 144. (A) T e use o beam restrictors limits the amount o tissue being irradiated, thus decreasing patient dose and decreasing the production o scattered radiation. High milliampere-second actors increase patient dose. Patient dose is reduced by using high-kilovolt and low–milliampere-second combinations. Although the use o a grid improves image quality by decreasing the amount o scattered radiation reaching the IR, it always requires an increase in exposure actor (usually milliampere-seconds) and, there ore, results in increased patient dose. 145. (D) Secondary radiation includes leakage and scattered radiation. T e control booth wall is a secondary barrier; there ore, the primary beam must never be directed toward it. T e x-ray tube housing must reduce leakage radiation to less than 100 mR/h at a distance o 1 m rom the housing. Lead aprons, lead gloves, portable x-ray barriers, and so on are also designed to protect the user rom exposure to scattered radiation and will not protect her or him rom the primary beam. 146. (D) Mobile radiography (along with uoroscopy and special procedures) is an area o higher occupational exposure. With no lead barrier to retreat behind, distance becomes the best source o protection. T e exposure switch o mobile equipment must be manu actured to allow the technologist to stand at least 6 f away rom the patient and the x-ray tube. T e least amount o scattered radiation is perpendicular to the scattering object, however, lead and distance have the greatest impact on personal protection during mobile imaging. A lead apron should be assigned to each mobile unit, and worn by the radiographer during the exposure. Hospital personnel, visitors, and patients also must be protected rom unnecessary radiation exposure. T ere ore, the radiographer must request that persons leave the immediate area until a er the exposure is made and announce in a loud voice when the exposure is about to be made, allowing time or individuals to leave the area.

147. (D) T e principal interactions that occur between x-ray photons and body tissues in the diagnostic x-ray range, the photoelectric e ect and Compton scatter, are ionization processes producing photoelectrons and recoil electrons that traverse tissue and subsequently ionize molecules. T ese interactions occur randomly but can lead to molecular damage in the orm o impaired unction or cell death. T e target theory speci es that DNA molecules are the targets o greatest importance and sensitivity; that is, DNA is the key sensitive molecule. However, since the body is 65% to 80% water, most interactions between ionizing radiation and body cells will involve radiolysis o water rather than direct interaction with DNA. T e two major types o e ects that occur are the direct e ect and the indirect e ect. T e direct e ect usually occurs with high-LE radiations and when ionization occurs at the DNA molecule itsel . T e indirect e ect, which occurs most requently, happens when ionization takes place away rom the DNA molecule in cellular water. However, the energy rom the interaction can be trans erred to the molecule via a ree radical ( ormed by radiolysis o cellular water). Possible damage to the DNA molecule is diverse. A single main-chain/side-rail scission (break) on the DNA molecule is repairable. A double main-chain/ side-rail scission may be repaired with dif culty or may result in cell death. A double main-chain/ side-rail scission on the same rung o the DNA ladder results in irreparable damage or cell death. Faulty repair o main-chain breakage can result in cross-linking. Damage to the nitrogenous bases, that is, damage to the base itsel or to the rungs connecting the main chains, can result in alteration o base sequences, causing a molecular lesion/point mutation. Any subsequent divisions result in daughter cells with incorrect genetic in ormation. 148. (D) As the amount o time one spends in a controlled area decreases, radiation exposure should decrease. Radiation exposure is a ected considerably by one’s proximity to the radiation source, as de ned by the inverse-square law. Barriers (shielding) are an e ective means o reducing radiation exposure; primary barriers, such as walls, protect one rom the primary beam, and secondary barriers, such as lead aprons, are used to protect one rom secondary radiation.

Answers: 144–158

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149. (A) T e e ects o a quantity o radiation delivered to a body depend on a ew actors, including the amount o radiation received, the size o the irradiated area, and how the radiation is delivered in time. I the radiation is delivered in portions over a period o time, it is said to be ractionated and has a less harm ul e ect than i the radiation were delivered all at once. Cells have an opportunity to repair, and some recovery occurs between doses.

newly ertilized ovum to even scattered radiation. I a riend or relative is not available, a nurse or transporter may be asked or help. Protective apparel, such as lead apron and gloves, must be provided to the person(s) holding the patient. It is the protocol o many radiology departments that radiology personnel must never assist in holding patients. In any case, the individual assisting must never be in the path o the primary beam.

150. (B) Somatic e ects o radiation re er to those e ects experienced directly by the exposed individual, such as erythema, epilation, and cataracts. Genetic e ects o radiation exposure are caused by irradiation o the reproductive cells o the exposed individual and are transmitted rom one generation to the next.

155. (D) A controlled area is one that is occupied by radiation workers who are trained in radiation sa ety and who wear radiation monitors. T e exposure rate in a controlled area must not exceed 100 mR/week; its occupancy actor is considered to be 1, indicating that the area may always be occupied and, there ore, requires maximum shielding. An uncontrolled area is one occupied by the general population; the exposure rate there must not exceed 10 mR/week. Shielding requirements vary according to several actors, one being occupancy actor.

151. (A) T e x-ray tube’s glass envelope and oil coolant are considered inherent (built-in) ltration. T in sheets o aluminum are added to make a total o at least 2.5-mm Al equivalent ltration in equipment operated above 70 kVp. T is is done to remove the low-energy photons that serve only to contribute to patient skin dose. 152. (C) Erythema is the reddening o skin as a result o exposure to large quantities o ionizing radiation. It was one o the rst somatic responses to irradiation demonstrated to the early radiology pioneers. T e e ects o radiation exposure to the skin ollow a nonlinear, threshold dose–response relationship. An individual’s response to skin irradiation depends on the dose received, the period o time over which it was received, the size o the area irradiated, and the individual’s sensitivity. T e dose that it takes to bring about a noticeable erythema is re erred to as the SED. 153. (B) T e patient is the most important radiation scatterer during both radiography and uoroscopy. In general, at 1 m rom the patient, the intensity is reduced by a actor o 1,000 to about 0.1% o the original intensity. Successive scatterings can reduce the intensity to unimportant levels. 154. (B) I mechanical restraint is impossible, a relative or riend accompanying the patient may be requested/permitted to hold the patient. I a parent is to per orm this task, it is pre erable to elect the ather so as to avoid the possibility o subjecting a

156. (A) T e length o time rom conception to birth, that is, pregnancy, is re erred to as gestation. T e term congenital re ers to a condition existing at birth. Neonatal relates to the time immediately a er birth and the rst month o li e. In vitro re ers to something living outside a living body (as in a test tube), as opposed to in vivo (within a living system). 157. (B) It is well established that suf cient quantities o ionizing radiation can cause a number o serious somatic and/or genetic e ects. Somatic e ects o radiation are those that a ect the irradiated body itsel . Somatic e ects are described as being early or late depending on the length o time between irradiation and mani estation o e ects. T e human reproductive organs are particularly radiosensitive. Fertility and heredity are greatly a ected by the germ cells produced within the testes (spermatogonia) and ovaries (oogonia). Excessive radiation exposure to the gonads can cause temporary or permanent in ertility and/or genetic mutations. In ertility is somatic because it a ects the exposed individual; genetic mutations a ect uture generations. 158. (A) X-ray intensity is inversely related to SID; as SID increases, x-ray intensity decreases. T e x-ray

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intensity at the image intensi er also depends on the SID. Moving the image intensi er arther rom the patient increases the SID and decreases x-ray beam intensity at the input phosphor. T e automatic brightness control (ABC) would then increase the mA thereby increasing patient dose. Moving the image intensi er arther rom the patient also results in a longer OID, thereby increasing magni cation and diminishing image quality. 159. (C) Di erent types o monitoring devices are available or the occupationally exposed. Ionization is the undamental principle o operation o both the lm badge and the pocket dosimeter. T e pocket dosimeter contains an ionization chamber (containing air), and the number o ions ormed (o either sign) is equated to exposure dose. In the lm badge, the lm’s silver halide emulsion is ionized by x-ray photons. LDs are radiation monitors that use lithium uoride crystals. Once exposed to ionizing radiation and then heated, these crystals emit a quantity o light proportional to the amount o radiation received. OSL dosimeters are radiation monitors that use aluminum oxide crystals. T ese crystals, once exposed to ionizing radiation and then subjected to a laser, emit luminescence proportional to the amount o radiation received. 160. (B) With greater beam restriction, less biologic material is irradiated, thereby reducing the possibility o harm ul e ects. I less tissue is irradiated, less scattered radiation is produced, resulting in improved IR contrast. T e total ltration is not a unction o beam restriction but rather is a radiation protection guideline aimed at reducing patient skin dose. 161. (B) Radiation sa ety guidelines are valuable only i they are ollowed by radiation personnel. T e radiation sa ety of cer (RSO) is responsible or being certain that established guidelines are en orced and that personnel understand and employ radiation sa ety measures to protect themselves and their patients. T e RSO is also responsible or per orming routine equipment checks to ensure that all equipment meet radiation sa ety standards. 162. (B) T e genetic e ects o radiation and some somatic e ects, such as leukemia, are plotted on a linear

dose–response curve. T e linear dose–response curve has no threshold; that is, there is no dose below which radiation is absolutely sa e. T e nonlinear/sigmoidal dose–response curve has a threshold and is thought to be generally correct or most somatic e ects. 163. (C) T e development o male and emale reproductive stem cells has important radiation protection implications. Male stem cells reproduce continuously. However, emale stem cells develop only during etal li e; women are born with all the reproductive cells they will ever have. It is exceedingly important to shield children whenever possible because they have their reproductive utures ahead o them. 164. (B) As an x-ray source moves away rom an absorber, the x-ray intensity (quantity) decreases. Conversely, as the source o x-rays moves closer to the absorber, the intensity increases. In uoroscopy, the source o x-rays is 12 to 15 in below the x-ray tabletop. Since the source-to-object distance (SOD) is so short, patient skin dose can be quite high. Simply increasing the SID will decrease ESE, but mA will have to be increased to maintain the required exit exposure. Although mA is increased to maintain required exit exposure, because o the characteristic divergence o the x-ray beam, ESE will still be less at longer SIDs. Distance has a pro ound e ect on dose received and, there ore, is one o the cardinal rules o radiation protection. As distance rom the source increases, dose received decreases. 165. (A) It is our ethical responsibility to minimize the radiation dose to our patients. X-rays produced at the tungsten target make up a heterogeneous primary beam. T ere are many “so ” (low-energy) photons that, i not removed by lters, would only contribute to greater patient skin dose. T ey are too weak to penetrate the patient and contribute to the image- orming radiation; they penetrate a small thickness o tissue and are absorbed. 166. (D) Radiation quality determines degree o penetration and the amount o energy trans erred to the irradiated tissue (LE ). Certainly, the larger the absorbed radiation dose, the greater is the e ect. Biologic e ect is increased as the size o the irradiated area is increased. T e nature o the e ect is in uenced by the location o irradiated tissue (bone marrow vs. gonads).

Answers: 159–172

167. (D) Radiation e ects that appear days or weeks ollowing exposure (early e ects) are in response to relatively high radiation doses. T ese should never occur in diagnostic radiology today; they occur only in response to doses much greater than those used in diagnostic radiology. One o the e ects that may be noted in such a circumstance is the hematologic e ect—reduced numbers o white blood cells, red blood cells, and platelets in the circulating blood. Immediate local tissue e ects can include e ects on the gonads (i.e., temporary in ertility) and on the skin (e.g., epilation and erythema). Acute radiation lethality, or radiation death, occurs a er an acute exposure and results in death in weeks or days. Radiation-induced malignancy, leukemia, and genetic e ects are late e ects (or stochastic/probabilistic e ects) o radiation exposure. T ese can occur years a er survival o an acute radiation dose or a er exposure to low levels o radiation over a long period o time. Radiation workers need to be especially aware o the late e ects o radiation because their exposure to radiation is usually low level over a long period o time. Occupational radiation protection guidelines, there ore, are based on late e ects o radiation according to a linear, nonthreshold dose–response curve. 168. (A) T e most radiosensitive portion o the GI tract is the small bowel. Projecting rom the lining o the small bowel are villi, rom the epithelial crypts o Lieberkühn, which are responsible or the absorption o nutrients into the bloodstream. Because the epithelial cells o the villi are continually being cast o , new cells must continually arise rom the crypts o Lieberkühn. Being highly mitotic, undi erentiated stem cells, they are very radiosensitive. T us, the small bowel is the most radiosensitive portion o the GI tract. In the adult, the CNS is the most radioresistant system, and the epidermis is composed o radioresistant-mature, postmitotic cells. 169. (A) T e mAs setting regulates the quantity o radiation delivered to the patient, and the kVp setting regulates the quality (i.e., penetration) o the radiation delivered to the patient. T ere ore, higher-energy (i.e., more penetrating) radiation (which is more likely to exit the patient), accompanied by lower milliampere-seconds (mAs), is the sa est combination or the patient.

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170. (D) T e relationship between x-ray intensity and distance rom the source is expressed in the inverse-square law o radiation. T e ormula is 2 I1 D 2 = 2 I2 D1

Substituting known values: 10 36 = x 16 36x = 160 x = 4.44 T us, x = 4.44 mR in 60 minutes and, there ore, 1.48 mR in 20 minutes. Distance has a pro ound e ect on dose received and, there ore, is one o the cardinal rules o radiation protection. As distance rom the source increases, dose received decreases. 171. (B) Exposure dose to patients can be expressed as entrance skin exposure (ESE), sometimes re erred to as skin entrance exposure (SEE). Exposure can also be expressed in terms o organ dose. Organ doses to the gonads, bone marrow, breast, thyroid, lens, and lung can be determined. Patient position and beam restriction o en make a signi cant di erence in patient dose. Examinations per ormed PA rather than AP o en decrease exposure to sensitive organs. T is is so because the lower-energy x-ray photons will be absorbed by the anatomic structures closer to the x-ray source, and the higher-energy photons will penetrate and exit the part (penetrating the sensitive part rather than being absorbed by it). PA abdomen radiographs deliver less quantity dose to the reproductive organs than AP abdomen radiographs do. An AP lumbar spine radiograph, 7 × 17 inch IR, 80 kVp delivers about 74 mrad to the ovaries, whereas the same projection using a 14 × 17 inch IR delivers 92 mrad. An AP abdomen radiograph with 70 kVp delivers 80 mrad, whereas at 80 kVp, the ovarian dose is 68 mrad. 172. (A) Radiographers usually are required to wear one dosimeter, positioned at their collar and worn outside a lead apron. Special circumstances, however, warrant the use o a second monitor. During pregnancy, a second “baby monitor” is worn at the abdomen, under any lead apron. During special vascular procedures, the dose to the radiographer can increase signi cantly. T is is so because the leaded protective curtain is o en absent rom the uorotower and because o the extensive use o

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cineradiography. As a result, the radiographer’s upper extremities can receive a greater exposure (e.g., when assisting during catheter introduction), and a ring or bracelet badge is o en recommended. A second dosimeter is not required when per orming mobile radiography. 173. (B) T e reproductive cells are considered among the most radiosensitive cells in the body. T e immature emale sex cells are the oogonia; they mature to ova. T e immature male sex cells are the spermatogonia; they mature to sperm. Di erent amounts o ionizing radiation to these cells can cause di ering levels/degrees o response. Doses as low as 10 rad can cause menstrual changes in women and decrease the number o sperm in men. At 200 rad, temporary in ertility is likely, and at 500 rad, sterility will result. 174. (D) A LD is used to measure monthly exposure to radiation, as is the lm badge. Lithium uoride chips are the thermoluminescent material used in LDs. A pocket dosimeter (a small personal ionization chamber) measures the quantity o ionizations occurring during the period worn and reads out in millirem; it is used primarily when working with large quantities o radiation. 175. (B) It is important to limit tabletop exposure during uoroscopy because the SSD is so much less than in overhead radiography, so a much higher skin dose is delivered to the patient. For this reason, the tabletop exposure rate during uoroscopy should not exceed 10 R/min. 176. (C) Erythema is the reddening o skin as a result o exposure to large quantities o ionizing radiation. It was one o the rst somatic responses to irradiation demonstrated to the early radiology pioneers. Figure 3-7 illustrates three dose–response curves. Curve A begins at zero, indicating that there is no sa e dose, that is, no threshold. Even one x-ray photon theoretically can cause a response. It is a straight (linear) line, indicating that response is directly related to dose; as dose increases, response increases. Radiation-induced cancer, leukemia, and genetic e ects ollow a linear nonthreshold dose–response relationship. Curve B is another linear curve (response is directly related to dose), but this one illustrates that a particular dose o radiation must be received be ore a response will occur. T at is, there is a threshold dose;

this is called a linear threshold curve. Curve C is another threshold curve, but this curve is nonlinear. It illustrates that once the minimum dose is received, a response occurs slowly initially and then increases sharply as exposure increases. T is threshold, nonlinear (sigmoid) dose–response curve, illustrates the e ect to skin rom exposure to high levels o ionizing radiation. An individual’s response to skin irradiation depends on the dose received, the period o time over which it was received, the size o the area irradiated, and the individual’s sensitivity. T e dose that it takes to bring about a noticeable erythema is re erred to as the SED. 177. (A) T e intensity/exposure rate o radiation at a given distance rom a point source is inversely proportional to the square o the distance. T is is the inverse-square law o radiation, and it is expressed in the ollowing equation: 2 I1 D 2 = 2 I2 D1

Substituting known values: 40mR h 25 = x mR h 9 25x = 360 T us, x = 14.4 mR/h and, there ore, 7.2 mR in 30 minutes. 178. (B) In the photoelectric e ect, a relatively lowenergy photon uses all its energy to eject an innershell electron, leaving a vacancy. An electron rom the shell above drops down to ll the vacancy and in so doing gives up a characteristic ray. T is type o interaction is most harm ul to the patient because all the photon energy is trans erred to tissue. In Compton scatter, a high-energy incident photon ejects an outer-shell electron. T e incident photon is de ected with reduced energy, but it usually retains most o its energy and exits the body as an energetic scattered ray. T is scattered ray either will contribute to image og or will pose a radiation hazard to personnel depending on its direction o exit. In classic scatter, a low-energy photon interacts with an atom but causes no ionization; the incident photon disappears into the atom and then is released immediately as a photon o identical energy but with changed direction. Pair production is an interaction that occurs only at energies o 1.02 MeV, and there ore, it does not occur in diagnostic radiography.

Answers: 173–186

179. (C) Scattered and secondary radiations are those that have deviated in direction while passing through a part. Leakage radiation is radiation that emerges rom the leaded tube housing in directions other than that o the use ul beam. ube head construction must keep leakage radiation to less than 0.1 R/h at 1 m rom the tube. Remnant radiation is the radiation that emerges rom the patient to orm the radiographic image. 180. (D) T e presence o ionizing radiation may be detected in several ways. It has an ionizing e ect on air, which is the basic principle o the roentgen as unit o measurement. X-rays have a photographic e ect on lm emulsion, which is readily observable on radiographic images. T e uorescent e ect on certain crystals, such as calcium tungstate and lanthanum, accounts or our use o these phosphors in intensi ying screens. Radiation’s physiologic e ects have been demonstrated to be genetic damage, erythema, and cataractogenesis; many o these were noted by the early radiology pioneers. 181. (D) Irradiation during pregnancy, especially in early pregnancy, is avoided because the etus is particularly radiosensitive during the rst trimester. Especially high-risk examinations include pelvis, hip, emur, lumbar spine, cystograms and urograms, upper GI series, and barium enema (BE) examinations. During the 2nd through 10th weeks o pregnancy (i.e., during major organogenesis), etal anomalies can be produced. Skeletal and/or organ anomalies can appear i irradiation occurs early on, and neurologic anomalies can be ormed in the latter part; mental retardation and childhood malignant diseases can also result rom irradiation during the rst trimester. Fetal irradiation during the second and third trimesters, with suf cient dose, can cause some type o childhood malignant disease. Fetal irradiation during the rst 2 weeks o gestation most likely will result in embryonic resorption or spontaneous abortion. It must be emphasized that the likelihood o producing etal anomalies at doses below 20 rad is exceedingly small and that most general diagnostic examinations are likely to deliver etal doses o less than 1 to 2 rad. 182. (B) Even the smallest exposure to radiation can be harm ul. It, there ore, must be every radiographer’s objective to keep his or her occupational exposure as ar below the dose limit as possible. Radiology

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personnel never should hold patients during an x-ray examination. 183. (B) An approximate ESE can be determined using the illustrated nomogram. First, mark 2.5 mm Al on the x (horizontal) axis. Next, mark where a line drawn up rom that point intersects the 110-kVp line. Draw a line straight across to the y (vertical) axis; this should approximately reach the 12 mR/ mAs point. Because 1.5 mAs was used or the exposure, the approximate ESE is 18 mR (12 × 1.5). 184. (D) T e relationship between x-ray intensity and distance rom the source is expressed in the inverse-square law o radiation. T e ormula is 2 I1 D 2 = 2 I2 D1

Substituting known values: 104 64 = x 49 64 x = 6860 T us, x = 107 mR in 1 hour (60 minutes) and, there ore, 53.6 mR in 30 minutes. Note the inverse relationship between distance and dose. As distance rom the source o radiation increases, dose rate decreases signi cantly. 185. (B) Alpha and beta radiations are particulate radiations; alpha is composed o two protons and two neutrons, and beta is identical to an electron. Gamma and x-radiations are electromagnetic, having wave-like uctuations like other radiations o the electromagnetic spectrum (e.g., visible light and radio waves). 186. (D) T e Bucky slot cover shields the opening at the side o the table because the Bucky tray is parked at the end o the table or the uoroscopy procedure; this is important because the opening created otherwise would allow scattered radiation to emerge at approximately the level o the operator’s gonads. T e exposure switch (usually a oot pedal) must be o the “dead man” type; that is, when the oot is released rom the switch, there is immediate termination o exposure. T e cumulative exposure timer sounds or interrupts the exposure a er 5 minutes o uoro time, thus making the uoroscopist aware o accumulated uoro time. In addition, source-to-tabletop distance is restricted to at least 15 in or

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stationary equipment and at least 12 in or mobile equipment. Increased source-to-tabletop distance increases source-to-patient distance, thereby decreasing patient dose. 187. (C) As x-ray photons emerge rom the x-ray tube they immediately encounter air—be ore being intercepted by any material. T e roentgen has been the traditional unit o exposure; it measures the quantity o ionizations in air. T e roentgen, there ore, measures x-ray tube output—and an ion-chamber dosimeter instrument is used or this purpose. Rad is an acronym or radiation absorbed dose; it has been used measure the energy deposited in any material and has been replaced by the gray (Gy). Rem is an acronym or radiation-equivalent man; it includes the RBE speci c to the tissue irradiated and, there ore, is a valid unit o measurement or the dose to biologic material. Personal dosimeters still use the rem to report occupational exposure, however the unit has been largely replaced by the Sievert. Becqueral is the SI unit o measurement or radioactivity. 188. (D) All the tissues listed are considered especially radiosensitive. T e intestinal crypt cells o Lieberkühn are responsible or the absorption o nutrients into the bloodstream. Because these cells are continually being cast o , new cells must continually arise. Being highly mitotic undi erentiated stem cells, they are very radiosensitive. Excessive radiation to the blood- orming organs (such as bone marrow) can cause leukemia or li e-span shortening. Young, immature embryonic cells such as erythroblasts are listed among the most radiosensitive. Lymphocytes are the most radiosensitive cells in the body. 189. (D) Elective booking o a radiologic examination a er inquiring about the patient’s previous menstrual cycle is the most e ective means o preventing accidental exposure o a recently ertilized ovum. Patient questionnaires obtain this in ormation rom the patient and are also used o en in an in ormed consent orm. Patient postings in waiting and changing areas alert patients to advise the radiographer i there is any chance o pregnancy. T ese three sa eguards replace the earlier 10-day rule, which is now obsolete. 190. (A) In the photoelectric e ect, the incident (low-energy) photon is completely absorbed and thus is

responsible or producing contrast and contributing to patient dose. T e photoelectric e ect is the interaction between x-ray and tissue that predominates in the diagnostic range. In Compton scatter, only partial absorption occurs, and most energy emerges as scattered photons. In coherent scatter, no energy is absorbed by the part; it all emerges as scattered photons. Pair production occurs only at very high-energy levels, at least 1.02 MeV. 191. (B) T e OSL dosimeter and LD are used requently to measure the radiation exposure o radiographers. T e pocket dosimeter may be employed by radiation workers who are exposed to higher doses o radiation and need a daily reading. A blood test is an unacceptable method o monitoring radiation dose e ects because a very large dose would have to be received be ore blood changes would occur. 192. (B) T e genetically signi cant dose (GSD) illustrates that large exposures to a ew people are cause or little concern when diluted by the total population. On the other hand, we all share the burden o that radiation received by the total population, especially as the use o medical radiation increases, so each individual’s share o the total exposure increases. 193. (D) According to the NCRP, the annual occupational whole-body dose-equivalent limit is 50 mSv (5 rem or 5,000 mrem). T e annual occupational whole-body dose-equivalent limit or students under the age o 18 years is 1 mSv (100 mrem or 0.1 rem). T e annual occupational dose-equivalent limit or the lens o the eye is 150 mSv (15 rem). T e annual occupational dose-equivalent limit or the thyroid, skin, and extremities is 500 mSv (50 rem). T e total gestational dose-equivalent limit or the embryo/ etus o a pregnant radiographer is 5 mSv (500 mrem), not to exceed 0.5 mSv in 1 month. 194. (A) Restriction o eld size is one important method o patient protection. However, the accuracy o the light eld must be evaluated periodically as part o a quality assurance (QA) program. Guidelines or patient protection state that the collimator light and actual irradiated area must be accurate to within 2% o the SID. 195. (A) Lead aprons require certain maintenance and care i they are to continue to provide protection rom ionizing radiation. T ey can be kept clean

Answers: 187–200

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with a damp cloth. It is very important that they be hung when not in use rather than being olded or le in a heap between examinations. A olded or crumpled position encourages the ormation o cracks in the leaded vinyl. Lead aprons should be uoroscoped (at about 120 kVp) at least once a year to check or development o any cracks.

the uoroscopist to greatly reduce the exposure o the uoroscopist to energetic scatter rom the patient. As with overhead equipment, uoroscopic total ltration must be at least 2.5-mm Al equivalent to reduce excessive exposure to so radiation. Collimator–beam alignment must be accurate to within 2%.

196. (D) T e principal interactions that occur between x-ray photons and body tissues in the diagnostic x-ray range, the photoelectric e ect and Compton scatter, are ionization processes producing photoelectrons and recoil electrons that traverse tissue and subsequently ionize molecules. T ese interactions occur randomly but can lead to molecular damage in the orm o impaired unction or cell death. T e target theory speci es that DNA molecules are the targets o greatest importance and sensitivity; that is, DNA is the key sensitive molecule. However, since the body is 65% to 80% water, most interactions between ionizing radiation and body cells will involve radiolysis o water rather than direct interaction with DNA. T e two major types o e ects that occur are the direct e ect and the indirect e ect. T e direct e ect usually occurs with high-LE radiations and when ionization occurs at the DNA molecule itsel . T e indirect e ect, which occurs most requently, happens when ionization takes place away rom the DNA molecule in cellular water. However, the energy rom the interaction can be trans erred to the molecule via a ree radical ( ormed by radiolysis o cellular water).

198. (B) Because minerals in rocks and the earth can emanate radioactivity, high levels o radon gas inside homes have been o recent concern. Another source o radon gas is rom burning cigarettes, whether as a smoker or as passive exposure. Uranium miners have been identi ed with a much higher incidence o lung cancer; many o these individuals also were smokers. Radiology departments are not known as a source o radon gas exposure.

197. (D) T e protective curtain, which is usually made o leaded vinyl with at least 0.25-mm Pb equivalent, must be positioned between the patient and

199. (C) T e rst noticeable skin response to excessive irradiation would be erythema, a reddening o the skin very much like sunburn. Dry desquamation, a dry peeling o the skin, may ollow. Moist desquamation is peeling with associated puslike uid. Epilation, or hair loss, may be temporary or permanent depending on sensitivity and dose. 200. (D) Photoelectric interaction in tissue involves complete absorption o the incident photon, whereas Compton interactions involve only partial trans er o energy. T e larger the quantity o radiation and the greater the number o photoelectric interactions, the greater is the patient dose. Radiation to more radiosensitive tissues such as gonadal tissue or blood- orming organs is more harm ul than the same dose to muscle tissue.

Subspecialty List

QUESTION NUMBER AND SUBSPECIALTY correspond to subcategories in each o the f ve ARRT examination specif cation sections 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30.

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Biological aspects o radiation Radiation exposure and monitoring Personnel protection Biological aspects o radiation Radiation exposure and monitoring Minimizing patient exposure Minimizing patient exposure Biological aspects o radiation Radiation exposure and monitoring Radiation exposure and monitoring Biological aspects o radiation Radiation exposure and monitoring Personnel protection Radiation exposure and monitoring Biological aspects o radiation Radiation exposure and monitoring Minimizing patient exposure Personnel protection Personnel protection Personnel protection Biological aspects o radiation Personnel protection Biological aspects o radiation Radiation exposure and monitoring Personnel protection Minimizing patient exposure Minimizing patient exposure Minimizing patient exposure Radiation exposure and monitoring Personnel protection

31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65.

Radiation exposure and monitoring Biological aspects o radiation Biological aspects o radiation Minimizing patient exposure Biological aspects o radiation Minimizing patient exposure Radiation exposure and monitoring Biological aspects o radiation Biological aspects o radiation Biological aspects o radiation Minimizing patient exposure Minimizing patient exposure Personnel protection Radiation exposure and monitoring Biological aspects o radiation Minimizing patient exposure Minimizing patient exposure Radiation exposure and monitoring Biological aspects o radiation Radiation exposure and monitoring Biological aspects o radiation Biological aspects o radiation Radiation exposure and monitoring Biological aspects o radiation Biological aspects o radiation Biological aspects o radiation Biological aspects o radiation Biological aspects o radiation Biological aspects o radiation Radiation exposure and monitoring Minimizing patient exposure Personnel protection Radiation exposure and monitoring Minimizing patient exposure Personnel protection

Subspecialty List

66. 67. 68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 78. 79. 80. 81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92. 93. 94. 95. 96. 97. 98. 99. 100. 101. 102. 103. 104. 105. 106. 107. 108. 109. 110. 111. 112. 113. 114. 115.

Personnel protection Radiation exposure and monitoring Minimizing patient exposure Minimizing patient exposure Radiation exposure and monitoring Biological aspects o radiation Biological aspects o radiation Radiation exposure and monitoring Personnel protection Minimizing patient exposure Minimizing patient exposure Radiation exposure and monitoring Radiation exposure and monitoring Minimizing patient exposure Minimizing patient exposure Biological aspects o radiation Minimizing patient exposure Radiation exposure and monitoring Radiation exposure and monitoring Personnel protection Radiation exposure and monitoring Minimizing patient exposure Minimizing patient exposure Radiation exposure and monitoring Personnel protection Personnel protection Personnel protection Minimizing patient exposure Minimizing patient exposure Radiation exposure and monitoring Minimizing patient exposure Biological aspects o radiation Biological aspects o radiation Minimizing patient exposure Biological aspects o radiation Biological aspects o radiation Personnel protection Radiation exposure and monitoring Minimizing patient exposure Biological aspects o radiation Minimizing patient exposure Minimizing patient exposure Radiation exposure and monitoring Biological aspects o radiation Radiation exposure and monitoring Radiation exposure and monitoring Minimizing patient exposure Minimizing patient exposure Personnel protection Personnel protection

116. 117. 118. 119. 120. 121. 122. 123. 124. 125. 126. 127. 128. 129. 130. 131. 132. 133. 134. 135. 136. 137. 138. 139. 140. 141. 142. 143. 144. 145. 146. 147. 148. 149. 150. 151. 152. 153. 154. 155. 156. 157. 158. 159. 160. 161. 162. 163. 164. 165.

Minimizing patient exposure Minimizing patient exposure Radiation exposure and monitoring Biological aspects o radiation Biological aspects o radiation Radiation exposure and monitoring Radiation exposure and monitoring Personnel protection Biological aspects o radiation Biological aspects o radiation Personnel protection Biological aspects o radiation Minimizing patient dose Biological aspects o radiation Biological aspects o radiation Radiation exposure and monitoring Radiation exposure and monitoring Personnel protection Radiation exposure and monitoring Biological aspects o radiation Radiation exposure and monitoring Minimize patient dose Biological aspects o radiation Biological aspects o radiation Personnel protection Radiation exposure and monitoring Personnel protection Radiation exposure and monitoring Minimizing patient exposures Personnel protection Personnel protection Biological aspects o radiation Personnel protection Biological aspects o radiation Biological aspects o radiation Minimizing patient exposure Biological aspects o radiation Personnel protection Minimizing patient exposure Personnel protection Minimizing patient exposure Biological aspects o radiation Minimizing patient exposure Radiation exposure and monitoring Minimizing patient exposure Radiation exposure and monitoring Biological aspects o radiation Biological aspects o radiation Minimizing patient exposure Minimizing patient exposure

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178

166. 167. 168. 169. 170. 171. 172. 173. 174. 175. 176. 177. 178. 179. 180. 181. 182. 183.

3: Radiation Protection

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Targeted Reading Adler AM, Carlton RR. Introduction to Radiologic Sciences and Patient Care. 5th ed. St. Louis, MO: Saunders Elsevier; 2012. Selman J. T e Fundamentals o Imaging Physics and Radiobiology. 9th ed. Spring eld, IL: Charles C T omas; 2000. Statkiewicz-Sherer MA, Visconti PJ, Ritenour ER, Haynes KW. Radiation Protection in Medical Radiography. 7th ed. St. Louis, MO: Mosby; 2014. Fosbinder RA, Kelsey CA. Essentials o Radiologic Science. 1st ed. New York, NY: McGraw-Hill; 2002. Bontrager KL, Lampignano JP. extbook o Radiographic Positioning and Related Anatomy. 8th ed. St Louis, MO: Mosby; 2014.

184. 185. 186. 187. 188. 189. 190. 191. 192. 193. 194. 195. 196. 197. 198. 199. 200.

Personnel protection Radiation exposure and monitoring Minimizing patient exposure Radiation exposure and monitoring Biological aspects o radiation Minimizing patient exposure Biological aspects o radiation Personnel protection Biological aspects o radiation Radiation exposure and monitoring Minimizing patient exposure Personnel protection Biological aspects o radiation Personnel protection Biological aspects o radiation Biological aspects o radiation Biological aspects o radiation

Bushong SC. Radiologic Science or echnologists. 10th ed. St. Louis, MO: Mosby; 2013. Frank ED, Long BW, Smith BJ. Merrill’s Atlas o Radiographic Positioning and Procedures, Vols 1, 2, and 3. 12th ed. St. Louis, MO: Mosby; 2012. NCRP Report No. 116. Recommendations on Limits or Exposure to Ionizing Radiation. NCRP; 1987. NCRP Report No. 99. Quality Assurance or Diagnostic Imaging. NCRP; 1990. NCRP Report No. 160. Ionizing Radiation Exposure o the Population o the United States. NCRP; 2009. NCRP Report No. 102. Medical x-ray, Electron Beam and Gamma-Ray Protection or Energies up to 50 MeV (Equipment Design, Per ormance and Use). NCRP; 1989.

CHAPTER 4

Image Acquisition and Evaluation Questions

DIRECTIONS (Questions 1 through 250): Each of the numbered items or incomplete statements in this section is followed by answers or by completions of the statement. Select the one lettered answer or completion that is best in each case. 1. Misalignment o the tube–part–IR relationship results in (A) (B) (C) (D)

shape distortion size distortion magni cation blur

2. In digital imaging, brightness is controlled by

4. An algorithm, as used in x-ray imaging, is a (an) (A) (B) (C) (D)

geometric ormula speci c exposure actors series o variable instructions predetermined exposure actors

5. T e chest radiograph shown in Figure 4-1 demonstrates (A) (B) (C) (D)

part motion aliasing arti act double exposure grid cuto

1. IR exposure 2. monitor unctions 3. postprocessing unctions (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

3. In electronic imaging, as digital image matrix size increases 1. pixel size decreases 2. resolution decreases 3. pixel depth decreases (A) (B) (C) (D)

1 only 2 only 1 and 2 only 2 and 3 only

Figure 4-1. Courtesy of Stamford Hospital, Department of Radiology.

179

180

4: Image Acquisition and Evaluation

6. T e intensity o ionizing radiation decreases as

10. An increase in kilovoltage will have which o the ollowing e ects in digital imaging?

(A) distance rom the source o radiation decreases (B) distance rom the source o radiation increases (C) requency increases (D) wavelength decreases

1. More scattered radiation will be produced. 2. T e exposure rate will increase. 3. Radiographic contrast will increase. (A) (B) (C) (D)

7. Grid interspace material can be made o 1. carbon ber 2. aluminum 3. plastic ber (A) (B) (C) (D)

11. T e x-ray tube used in C must be capable o 1. high-speed rotation 2. short pulsed exposures 3. withstanding millions o heat units

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

8. T e reduction in x-ray photon intensity as the photon passes through material is termed (A) (B) (C) (D)

t n u

5

10

4

10

3

10

2

m e a

v i t

(A) (B) (C) (D)

double exposure inverted IP incomplete erasure image ading

3 De ns ity

A

l

c

a

e

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Line A is representative o CR DR. Line B is representative o CR DR. Neither line is representative o CR DR. Both lines are representative o CR DR.

o

10

(A) (B) (C) (D)

12. What is the correct critique o the CR image shown in Figure 4-3?

absorption scattering attenuation divergence

9. Which o the lines indicated in Figure 4-2 represents the dynamic range o ered by computed radiography digital radiography (CR DR)? (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

10 1

u

m

i

n

I

e

P

s

'

s

c

e

r

e

n

2

1

l

B 10 0 10

-2

-1

0

1

10 10 10 Expos ure dos e (mR)

10

2

Figure 4-2. Courtesy FUJIFILM Medical Systems USA, Inc.

10

3

Figure 4-3. Courtesy of Stamford Hospital, Department of Radiology.

Questions: 6–20

13. I a lateral projection o the chest is being perormed on an asthenic patient and the outer photocells are selected, what is likely to be the outcome? (A) (B) (C) (D)

Decreased IR exposure Increased IR exposure Scattered radiation og Motion blur

14. Which o the ollowing groups o exposure actors will produce the greatest receptor exposure? (A) (B) (C) (D)

100 mA, 50 ms 200 mA, 40 ms 400 mA, 70 ms 600 mA, 30 ms

15. T e component o a CR image plate (IP) that records the radiologic image is the (A) (B) (C) (D)

emulsion helium–neon laser photostimulable phosphor scanner–reader

16. An x-ray image o the ankle was made at 40-SID, 200 mA, 50 ms, 70 kV, 0.6-mm ocal spot, and minimal OID. Which o the ollowing modi cations would result in the greatest increase in magni cation? (A) (B) (C) (D)

1.2-mm ocal spot 36-in SID 44-in SID 4-in OID

17. T e radiation dose received by the digital detector or each image is indicated by the (A) (B) (C) (D)

mA meter exposure indicator kV selector histogram

181

18. HVL is a ected by the amount o 1. kVp 2. beam ltration 3. tissue density (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

19. T e luminescent light emitted by the PSP is transormed into the image seen on the CR by the (A) (B) (C) (D)

PSP scanner–reader ADC helium–neon laser

20. T e lateral coccyx image shown in Figure 4-4 was made using AEC but is overexposed. T is is most likely a result o (A) (B) (C) (D)

incorrect selection o the small ocal spot insu cient backup time selection o the center photocell incorrect centering o the part

182

4: Image Acquisition and Evaluation

Figure 4-4. Reproduced, with permission, from Shephard CT. Radiographic Image Production and Manipulation. New York, NY: McGraw-Hill; 2003.

21. Which o the ollowing units is (are) used to express resolution? 1. Line-spread unction 2. Line pairs per millimeter 3. Line- ocus principle (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

22. T e term windowing describes the practice o (A) varying the automatic brightness control (B) changing the image brightness and or contrast scale (C) varying the FOV (D) increasing resolution

23. Foreshortening can be caused by (A) the radiographic object being placed at an angle to the IR (B) excessive distance between the object and the IR (C) insu cient distance between the ocus and the IR (D) excessive distance between the ocus and the IR 24. Acceptable method(s) o unsharpness is (are) 1. suspended respiration 2. short exposure time 3. patient instruction (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

minimizing motion

Questions: 21–30

25. Using xed milliampere-seconds and variable kilovoltage technical actors, each centimeter increase in patient thickness requires what adjustment in kilovoltage? (A) (B) (C) (D)

28. Factors that contribute to lm og include 1. the age o the lm 2. excessive exposure to sa elight 3. processor chemistry

Increase 2 kV Decrease 2 kV Increase 4 kV Decrease 4 kV

(A) (B) (C) (D)

26. Unopened boxes o radiographic lm should be stored away rom radiation and (A) (B) (C) (D)

1. photon wavelength 2. applied milliamperes (mA) 3. applied kilovoltage (kV)

in the horizontal position in the vertical position stacked with the oldest on top stacked with the newest on top

(A) (B) (C) (D)

1. PACS 2. annotation 3. inversion reversal

A

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

29. X-ray photon energy is inversely related to

27. Potential digital image postprocessing tasks include

(A) (B) (C) (D)

183

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

30. Which o the radiographs shown in Figure 4-5 most likely required the greater exposure?

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

(A) Image A (B) Image B (C) No di erence in exposure was required

B

Figure 4-5. From the American College of Radiology Learning File. Courtesy of the ACR.

184

4: Image Acquisition and Evaluation

31. Characteristics o DR imaging include 1. solid-state detector receptor plates 2. a direct-capture imaging system 3. immediate image display (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 1, 2, and 3

32. Compared with a low-ratio grid, a high-ratio grid will 1. allow more centering latitude 2. absorb more scattered radiation 3. absorb more primary radiation (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

33. A decrease in kilovoltage will result in 1. a decrease in image resolution 2. a decrease in photon energy 3. a decrease in receptor exposure (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

34. What is the correct critique o the CR image shown in Figure 4-6? (A) (B) (C) (D)

double exposure inverted IP incomplete erasure image ading

Figure 4-6. Courtesy of Stamford Hospital, Department of Radiology.

35.

o be suitable or use in an image intensi er’s input screen, a phosphor should have which o the ollowing characteristics? 1. High conversion e ciency 2. High x-ray absorption 3. High atomic number (A) (B) (C) (D)

1 only 3 only 1 and 2 only 1, 2, and 3

36. Resolution in CR increases as 1. laser beam size decreases 2. monitor matrix size decreases 3. PSP crystal size decreases (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

Questions: 31–40

37. What pixel size has a 512 × 512 matrix with a 20-cm eld o view (FOV)? (A) (B) (C) (D)

0.07 mm pixel 0.40 mm pixel 0.04 mm pixel 4.0 mm pixel

38. In radiography o a large abdomen, which o the ollowing is (are) e ective way(s) to minimize the amount o scattered radiation reaching the image receptor (IR)? 1. Use o close collimation 2. Use o low mAs 3. Use o a low-ratio grid A

(A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

39. Which o the ollowing actors contribute(s) to the e cient per ormance o a grid? 1. Grid ratio 2. Number o lead strips per inch 3. Amount o scatter transmitted through the grid (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

B

40. T e changes between the images shown in Figure 4-7 represent changes made to (A) (B) (C) (D)

pixel size matrix size window width window level

C

Figure 4-7. Courtesy of Stamford Hospital, Department of Radiology.

185

186

4: Image Acquisition and Evaluation

41. All the ollowing a ect the exposure rate o the primary beam except (A) milliamperage (B) kilovoltage (C) distance (D) eld size

(A) (B) (C) (D)

42. Which o the ollowing terms is used to describe unsharp edges o tiny radiographic details? (A) (B) (C) (D)

1. di erential tissue absorption 2. atomic number o tissue being traversed 3. proper regulation o milliampere-seconds

46. In comparison with 60 kV, 80 kV (in analog screen– lm imaging) will

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

(A) (B) (C) (D)

(A) (B) (C) (D)

3:1 5:1 10:1 16:1

1 only 2 only 1 and 2 only 2 and 3 only

47. T e term pixel is associated with all o the ollowing except

44. What grid ratio is represented in Figure 4-8? (A) (B) (C) (D)

5.1 in 5.7 in 6.1 in 6.7 in

1. permit greater exposure latitude 2. produce more scattered radiation 3. produce shorter-scale contrast

Di usion Mottle Blur Umbra

43. Image contrast, in screen– lm imaging, is a result o

(A) (B) (C) (D)

45. A 5-in object to be radiographed at a 44-in SID lies 6 in rom the IR. What will be the image width?

two dimensional picture element measured in xy direction how much o the part is included in the matrix

48. Geometric blur can be evaluated using all the ollowing devices except

1.0 mm

(A) (B) (C) (D)

star pattern slit camera penetrometer pinhole camera

49. Causes o grid cuto , when using ocused reciprocating grids, include the ollowing?

5 mm

0.5 mm

1. Inadequate SID 2. X-ray tube o -center with the long axis o the lead strips 3. Angling the beam in the direction o the lead strips (A) (B) (C) (D)

Figure 4-8.

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Questions: 41–56

50. T e tiny increased brightness, dropout arti acts, seen in the proximal portion o the CR image o the radius shown in Figure 4-9 are representative o (A) (B) (C) (D)

backscatter skipped scan lines dust dirt on the PSP image ading

187

52. Which o the ollowing groups o actors would produce the least radiographic density in analog screen– lm imaging)? (A) 400 mA, 0.010 second, 94 kV, 100-speed screens (B) 500 mA, 0.008 second, 94 kV, 200-speed screens (C) 200 mA, 0.040 second, 94 kV, 50-speed screens (D) 100 mA, 0.020 second, 80 kV, 200-speed screens 53. Chemical og on a radiographic lm image may be attributed to 1. excessive developer temperature 2. oxidized developer 3. excessive replenishment (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

54. Because o the anode heel e ect, the intensity o the x-ray beam is greatest along the (A) (B) (C) (D)

path o the central ray anode end o the beam cathode end o the beam transverse axis o the IR

55. T e di erences between CR and DR include 1. CR uses IPs. 2. CR has higher DQE and lower patient dose. 3. CR images are displayed immediately.

Figure 4-9. Reproduced, with permission, from Shephard CT. Radiographic Image Production and Manipulation. New York: McGraw-Hill; 2003.

51. Using a short (25–30 in) SID with a large (14 × 17 in) IR is likely to (A) (B) (C) (D)

increase the scale o contrast increase the anode heel e ect cause mal unction o the AEC cause premature termination o the exposure

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

56. T e term voxel is associated with all o the ollowing except (A) bit depth (B) volume element (C) measured in Z direction (D) eld o view

188

4: Image Acquisition and Evaluation

57. Using a 48-in SID, how much OID must be introduced to magni y an object two times? (A) (B) (C) (D)

1. light shield layer 2. support layer 3. electroconductive layer

8-in OID 12-in OID 16-in OID 24-in OID

58. A particular radiograph was produced using 12 mAs and 85 kV with a 16:1 ratio grid. T e radiograph is to be repeated using an 8:1 ratio grid. What should be the new milliampere-seconds value? (A) (B) (C) (D)

61. T e photostimulable phosphor (PSP) plates used in CR are constructed in layers that include

3 6 8 10

59. T e main di erence between the direct-capture and indirect-capture DR is that (A) direct capture conversion has no scintillator (B) direct capture conversion uses a photostimulable phosphor (C) in direct capture conversion, light is detected by CCDs (D) in direct capture conversion, light is detected by F s

(A) (B) (C) (D)

62. For the same FOV, spatial resolution will be improved using (A) (B) (C) (D)

CR DR SF Direct conversion

a smaller matrix a larger matrix ewer pixels shorter SID

63. Which o the ollowing are methods o limiting the production o scattered radiation? 1. Using moderate ratio grids 2. Using the prone position or abdominal examinations 3. Restricting the eld size to the smallest practical size (A) (B) (C) (D)

60. Analog-to-digital conversion is required in the ollowing imaging system (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

64.

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

wo screen– lm images o the skull are shown in Figure 4-10. Which o the ollowing best describes their di erent appearance? (A) (B) (C) (D)

Image B was made using a grid. Image A demonstrates higher contrast. Image A demonstrates motion. Image B demonstrates shape distortion.

Questions: 57–66

A

B

Figure 4-10. A and B. From the American College of Radiology Learning File. Courtesy of the ACR.

65. T e absorption o use ul radiation by a grid is called (A) (B) (C) (D)

grid selectivity grid cleanup grid cuto latitude 1

2

3

4

66. Which o the images in Figure 4-11 has the largest matrix size? (A) (B) (C) (D)

Image #1 Image #2 Image #3 Image #4

Figure 4-11.

189

190

67.

4: Image Acquisition and Evaluation

ypes o shape distortion include 1. magni cation 2. elongation 3. oreshortening (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

68. For the same FOV, as the matrix size increases 1. spatial resolution increases 2. image quality increases 3. pixel size decreases (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

69. In digital imaging, as the size o the image matrix increases, 1. FOV increases 2. pixel size decreases 3. spatial resolution increases (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

70. All the ollowing are related to spatial resolution except (A) (B) (C) (D)

milliamperage ocal-spot size SID OID

71. A satis actory radiograph was made using a 36-in SID, 12 mAs, and a 12:1 grid. I the examination will be repeated at a distance o 42 in and using a 5:1 grid, what should be the new milliampere-seconds value to maintain the original receptor exposure? (A) (B) (C) (D)

5.6 6.5 9.7 13

72. O the ollowing groups o exposure actors, which will produce the most receptor exposure? (A) (B) (C) (D)

400 mA, 30 ms, 72-in SID 200 mA, 30 ms, 36-in SID 200 mA, 60 ms, 36-in SID 400 mA, 60 ms, 72-in SID

73. Which o the ollowing groups o analog screen– lm exposure actors will produce the shortest scale o contrast? (A) (B) (C) (D)

200 mA, 0.08 second, 95 kV, 12:1 grid 500 mA, 0.03 second, 70 kV, 8:1 grid 300 mA, 0.05 second, 95 kV, 8:1 grid 600 mA, ¹/ second, 70 kV, 6:1 grid

74. All o the ollowing statements regarding digital imaging are true, except (A) window level adjustments are associated with image brightness. (B) brightness is related to IR exposure. (C) image visibility is a unction o IR exposure. (D) brightness and density are not interchangeable terms. 75. In digital imaging, kV selection has an e ect on 1. photon energy 2. penetration 3. image contrast (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

76. Which o the ollowing actors in uence(s) the production o scattered radiation? 1. Kilovoltage level 2. issue density 3. Size o eld (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

Questions: 67–86

77. Exposure actors o 2 mAs and 75 kV were used or a particular part. Which o the ollowing changes would result in twice the exposure to the image receptor? (A) (B) (C) (D)

1 mAs 4 mAs 76 kV 64 kV

78. Factors impacting spatial resolution include 1. Focal-spot size 2. Subject motion 3. SOD (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

79. Which o the ollowing is (are) tested as part o a quality assurance (QA) program? 1. Beam alignment 2. Reproducibility 3. Linearity (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

80. Focal-spot blur is greatest (A) (B) (C) (D)

directly along the course o the central ray toward the cathode end o the x-ray beam toward the anode end o the x-ray beam as the SID is increased

81. How are mAs and patient dose related? (A) mAs and patient dose are inversely proportional. (B) mAs and patient dose are directly proportional. (C) mAs and patient dose are unrelated. (D) mAs and patient dose are inversely related.

191

82. Image plate ront material can be made o which o the ollowing? 1. Carbon ber 2. Magnesium 3. Lead (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

83. Which o the ollowing pathologic conditions would require a decrease in exposure actors? (A) (B) (C) (D)

Congestive heart ailure Pneumonia Emphysema Pleural e usion

84. An exposure was made at a 36-inch SID using 300 mA, a 30-ms exposure, and 80 kV and an 8:1 grid. It is desired to repeat the radiograph using a 40-inch SID and 70 kV. With all other actors remaining constant, what new exposure time will be required? (A) (B) (C) (D)

0.03 second 0.07 second 0.14 second 0.36 second

85. Practice(s) that enable the radiographer to reduce the exposure time required or a particular image include 1. use o a higher milliamperage 2. use o a higher kilovoltage 3. use o a higher ratio grid (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

86. I 400 mA, 10 ms, and 90 kV were used or a particular exposure using three-phase, 12-pulse equipment, which o the ollowing exposure changes would be most appropriate or use on single-phase equipment to produce a similar image? (A) (B) (C) (D)

Use 200 mA Use 20 mAs Use 70 kV Use 0.02 second

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4: Image Acquisition and Evaluation

87. Which o the ollowing materials may be used as grid interspace material? 1. Lead 2. Plastic 3. Aluminum (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

88. T e radiograph shown in Figure 4-12 demonstrates an example o (A) (B) (C) (D)

motion blur underexposure scanner reader arti act exposure arti act

89. Exposure-type arti acts include 1. double exposure 2. motion 3. image ading (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

90. An increase in the kilovoltage applied to the x-ray tube increases the 1. x-ray wavelength 2. exposure rate 3. patient absorption (A) (B) (C) (D)

1 only 2 only 2 and 3 only 1, 2, and 3

91. Which o the ollowing statements about histograms is are true? 1. A histogram illustrates pixel value distribution. 2. T ere is a de ault histogram or each di erent body parts. 3. A histogram is representative o the image grayscale. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

92. Which o the ollowing is the correct order o radiographic lm processing? (A) (B) (C) (D)

Figure 4-12. Courtesy of Stamford Hospital, Department of Radiology.

Developer, wash, xer, dry Fixer, wash, developer, dry Developer, xer, wash, dry Fixer, developer, wash, dry

93. I the radiographer is unable to achieve a short OID because o the structure o the body part or patient condition, which o the ollowing adjustments can be made to minimize magni cation distortion? (A) (B) (C) (D)

A smaller ocal-spot size should be used. A longer SID should be used. A shorter SID should be used. A lower-ratio grid should be used.

Questions: 87–100

94. T e exposure actors used or a particular nongrid x-ray image were 300 mA, 4 ms, and 90 kV. Another image, using an 8:1 grid, is requested. Which o the ollowing groups o actors is most appropriate? (A) (B) (C) (D)

400 mA, 3 ms, 110 kV 400 mA, 12 ms, 90 kV 300 mA, 8 ms, 100 kV 200 mA, 240 ms, 90 kV

95. T e PA chest image shown in Figure 4-13 exhibits which o the ollowing qualities? 1. Adequate penetration o the heart 2. Long-scale contrast 3. Adequate inspiration (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

193

96. Exposure rate will decrease with an increase in 1. SID 2. kilovoltage 3. ocal-spot size (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

97. Which o the ollowing pathologic conditions probably will require a decrease in exposure actors? (A) (B) (C) (D)

Osteomyelitis Osteoporosis Osteosclerosis Osteochondritis

98. Diagnostic x-rays are generally associated with (A) (B) (C) (D)

high requency and long wavelength high requency and short wavelength low requency and long wavelength low requency and short wavelength

99. A screen– lm image exhibiting insu cient density might be attributed to 1. inadequate kilovoltage 2. inadequate SID 3. grid cuto (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

100. Decreasing eld size rom 14 × 17 in to 8 × 10 in, with no other changes, will

Figure 4-13. Reproduced, with permission, from Slone RM, Guitierrez FR, Fisher AJ. Thoracic Imaging. New York: McGraw-Hill; 1999.

(A) decrease the amount o scattered radiation generated within the part (B) increase the amount o scattered radiation generated within the part (C) increase x-ray penetration o the part (D) decrease x-ray penetration o the part

194

4: Image Acquisition and Evaluation

101. Which o the ollowing devices is used to overcome severe variation in patient anatomy or tissue density, providing more uni orm receptor exposure? (A) (B) (C) (D)

Compensating lter Grid Collimator Added ltration

102. What are the e ects o scattered radiation on a radiographic image? 1. It produces og. 2. It increases contrast. 3. It increases grid cuto . (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

106. In digital imaging, mAs selection has an e ect on 1. receptor exposure 2. patient dose 3. density (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

107. T e x-ray image seen in Figure 4-14 is most likely the result o (A) (B) (C) (D)

an o -level grid pronounced anode heel e ect too low mAs actors too low kVp actors

103. Which o the ollowing groups o exposure actors would be most appropriate to control involuntary motion? (A) (B) (C) (D)

400 mA, 0.03 second 200 mA, 0.06 second 600 mA, 0.02 second 100 mA, 0.12 second

104. Spatial resolution detail can be improved by decreasing 1. the SID 2. the OID 3. patient part motion (A) (B) (C) (D)

1 only 3 only 2 and 3 only 1, 2, and 3

105. T e unction(s) o the developer in lm processing is (are) to 1. remove the unexposed silver bromide crystals 2. change the exposed silver bromide crystals to black metallic silver 3. harden the emulsion (A) (B) (C) (D)

1 only 2 only 1 and 3 only 2 and 3 only

Figure 4-14. Courtesy of Stamford Hospital, Department of Radiology.

Questions: 101–116

108. Which o the ollowing a ect(s) both the quantity and the quality o the primary beam? 1. Hal -value layer (HVL) 2. Kilovoltage (kV) 3. Milliamperage (mA) (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

109. In which o the ollowing ways does SID a ect spatial resolution? (A) Spatial resolution is directly related to SID. (B) Spatial resolution is inversely related to SID. (C) As SID increases, spatial resolution decreases. (D) SID is not a resolution actor. 110. Which o the ollowing would be use ul or an examination o a patient su ering rom Parkinson’s disease? 1. Short exposure time 2. Decreased SID 3. Compensating ltration (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

111. Underexposure o an SF radiograph can be caused by all the ollowing except insu cient (A) (B) (C) (D)

milliamperage (mA) exposure time Kilovoltage SID

112. I a duration o 0.05 second was selected or a particular exposure, what milliamperage would be necessary to produce 30 mAs? (A) (B) (C) (D)

900 600 500 300

195

113. An anteroposterior (AP) projection o the emur was made using 300 mA, 0.03 second, 76 kV, 40-in SID, 1.2-mm ocal spot, and a 400-speed screen– lm system. With all other actors remaining constant, which o the ollowing exposure times would be required to maintain correct IR exposure at a 44-in SID using 500 mA? (A) (B) (C) (D)

12 ms 22 ms 30 ms 36 ms

114. An AP radiograph o the emur was made using 300 mA, 30 ms, 76 kV, 40-in SID, and 1.2-mm ocal spot. With all other actors remaining constant, which o the ollowing exposure times would be required to maintain correct IR exposure using 87 kV and the addition o a 12:1 grid? (A) (B) (C) (D)

38 ms 60 ms 75 ms 150 ms

115. Which o the ollowing statements regarding dual x-ray absorptiometry is (are) true? 1. Radiation dose is low. 2. Only low-energy photons are used. 3. Photon attenuation by bone is calculated. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

116. In a posteroanterior (PA) projection o the chest being used or cardiac evaluation, the heart measures 14.7 cm between its widest points. I the magni cation actor is known to be 1.2, what is the actual diameter o the heart? (A) (B) (C) (D)

10.4 cm 12.25 cm 13.5 cm 17.64 cm

196

4: Image Acquisition and Evaluation

117. Bone densitometry is of en per ormed to 1. measure degree o bone (de) mineralization 2. evaluate the results o osteoporosis treatment therapy 3. evaluate the condition o sof tissue adjacent to bone (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

118. T e di erences between CR and DR include 1. DR images are displayed immediately. 2. DR has higher DQE and lower patient dose. 3. DR uses IPs. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

119. Which o the ollowing errors is illustrated in Figure 4-15? (A) (B) (C) (D)

Patient not centered to IR X-ray tube not centered to grid Inaccurate collimation Unilateral grid cuto

120. T e process o “windowing” o digital images determines the image (A) (B) (C) (D)

spatial resolution contrast pixel size matrix size

121. What is the purpose o the thin layer o lead that is of en located in the rear portion o an IP? (A) (B) (C) (D)

o prevent crossover o increase speed o di use light photons o prevent scattered radiation og

122. T e purpose o the electroconductive layer o a CR PSP plate is to (A) provide support to the PSP layer (B) provide mechanical strength (C) acilitate transportation through the scanner reader (D) provide better resolution 123. Which o the ollowing combinations is most likely to be associated with quantum mottle? (A) Decreased milliampere-seconds, decreased SID (B) Increased milliampere-seconds, decreased kilovoltage (C) Decreased milliampere-seconds, increased kilovoltage (D) Increased milliampere-seconds, increased SID 124. What pixel size has a 2,048 × 2,048 matrix with a 60-cm FOV? (A) (B) (C) (D)

0.3 mm 0.5 mm 0.15 mm 0.03 mm

125. As window level increases

Figure 4-15. Courtesy of Stamford Hospital, Department of Radiology.

(A) (B) (C) (D)

contrast scale increases contrast scale decreases brightness increases brightness decreases

Questions: 117–133

126. Which o the ollowing matrix sizes is most likely to produce the best image resolution? (A) (B) (C) (D)

128 × 128 512 × 512 1,024 × 1,024 2,048 × 2,048

127. T e device shown in Figure 4-16 is used or (A) (B) (C) (D)

C and MR QA testing timer and recti er testing mammographic QA testing kilovoltage calibration testing

197

129. Examples o healthcare in ormatics include 1. HIS 2. RIS 3. PACS (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

130. T e exposure actors o 400 mA, 17 ms, and 82 kV produce a milliampere-seconds value o (A) (B) (C) (D)

2.35 6.8 23.5 68

131. All the ollowing statements regarding CR IPs are true except (A) (B) (C) (D)

IPs do not contain radiographic lm. IPs use no intensi ying screens. IPs must exclude all white light. IPs unction to protect the PSP.

132. T e radiographic accessory used to measure the thickness o body parts in order to determine optimal selection o exposure actors is the

Figure 4-16. Courtesy of Gammex Inc.

128. Factors that determine spatial resolution in digital imaging include 1. part motion 2. geometric actors 3. size o ocal spot (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

(A) (B) (C) (D)

ulcrum caliper densitometer ruler

133. T e x-ray image seen on the computer display monitor is a (an) (A) (B) (C) (D)

analog image digital image phosphor image emulsion image

198

4: Image Acquisition and Evaluation

134. Modi cations to the degree o digital image brightness can be made by adjustments to 1. total IR exposure 2. monitor controls 3. window level postprocessing (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

1. Lateral thoracic spine 2. AP emur 3. Right anterior oblique (RAO) sternum 1 only 1 and 2 only 1 and 3 only 1, 2, and 3

(A) (B) (C) (D)

photon energy grid ratio OID ocal-spot size

137. A radiograph made with a parallel grid demonstrates decreased receptor exposure on its lateral edges. T is is most likely due to

135. For which o the ollowing examinations can the anode heel e ect be an important consideration?

(A) (B) (C) (D)

136. All the ollowing have an impact on radiographic contrast except

(A) (B) (C) (D)

static electrical discharge the grid being o -centered improper tube angle decreased SID

138. What is the correct critique o the CR image shown in Figure 4-17? (A) (B) (C) (D)

Double exposure Grid centering error Incorrect AEC photocell Inverted ocused grid

Figure 4-17. From the American College of Radiology Learning File. Courtesy of the ACR.

Questions: 134–147

139. A particular milliampere-seconds value, regardless o the combination o milliamperes and time, will reproduce the same receptor exposure. T is is a statement o the (A) (B) (C) (D)

line- ocus principle inverse square law reciprocity law law o conservation o energy

140. OID is related to spatial resolution in which o the ollowing ways? (A) (B) (C) (D)

Spatial resolution is directly related to OID. Spatial resolution is inversely related to OID. As OID increases, so does spatial resolution. OID is unrelated to spatial resolution.

141. I 300 mA has been selected or a particular exposure, what exposure time would be required to produce 6 mAs? (A) (B) (C) (D)

5 ms 10 ms 15 ms 20 ms

199

145. Spatial resolution is inversely related to 1. SID 2. OID 3. part motion (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

146. O the ollowing groups o SF exposure actors, which will produce the shortest scale o radiographic contrast? (A) (B) (C) (D)

500 mA, 0.040 second, 70 kV 100 mA, 0.100 second, 80 kV 200 mA, 0.025 second, 92 kV 700 mA, 0.014 second, 80 kV

147. T e arti act seen in Figure 4-18 represents (A) (B) (C) (D)

CR processing arti act static electrical discharge cleaning solution arti act secondary exposure arti act

142. In digital imaging, as DEL size decreases (A) (B) (C) (D)

brightness increases brightness decreases spatial resolution increases spatial resolution decreases

143. An increase in kilovoltage will serve to (A) (B) (C) (D)

increase image brightness decrease image brightness increase photon energy decrease tissue penetration

144. T e unctions o automatic beam limitation devices include 1. reducing the production o scattered radiation 2. increasing the absorption o scattered radiation 3. changing the quality o the x-ray beam (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

Figure 4-18. Reproduced with permission from Saia DA. Radiography PREP Program Review and Exam Preparation. 7th ed. New York, NY: McGraw-Hill; 2012.

200

4: Image Acquisition and Evaluation

148. Magni cation uoroscopy is accomplished by 1. moving the image intensi er ocal point urther rom the output phosphor 2. selecting a smaller portion o the input phosphor 3. decreasing the voltage to the electrostatic lenses (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

(A) (B) (C) (D)

Pinhole camera Slit camera Star pattern Bar pattern

152. Focusing distance is associated with which o the ollowing?

149. Figure 4-19 is representative o (A) (B) (C) (D)

151. Which o the ollowing requires two exposures to evaluate ocal-spot accuracy?

the anode heel e ect the line- ocus principle the inverse square law the reciprocity law

(A) (B) (C) (D)

Computed tomography Chest radiography Magni cation radiography Grids

153. T e processing algorithm represents the (A) (B) (C) (D)

pixel value distribution anatomical part and projection image grayscale screen speed

154. T e relationship between the height o a grid’s lead strips and the distance between them is re erred to as grid (A) (B) (C) (D)

A 75%

CR 100%

B 120%

Figure 4-19.

150. O the ollowing groups o technical actors, which will produce the greatest radiographic receptor exposure? (A) (B) (C) (D)

10 mAs, 74 kV, 44-in SID 10 mAs, 74 kV, 36-in SID 5 mAs, 85 kV, 48-in SID 5 mAs, 85 kV, 40-in SID

ratio radius requency ocusing distance

155. Greater latitude in analog screen– lm imaging is available to the radiographer in which o the ollowing circumstances? 1. Using high kV technical actors 2. Using a low-ratio grid 3. Using low kV technical actors (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 3 only

Questions: 148–162

156. Characteristics o high-ratio ocused grids, compared with lower-ratio grids, include which o the ollowing? 1. T ey allow more positioning latitude. 2. T ey are more e cient in collecting SR. 3. T ey absorb more o the use ul beam. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

157. Factors that can a ect histogram appearance include 1. beam restriction 2. centering errors 3. incorrect SID (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

158. Figure 4-20 was made using screen– lm technique. T e area o blurriness seen in the upper part o the radiograph shown is most likely due to (A) (B) (C) (D)

scattered radiation og patient motion poor screen– lm contact grid cuto

201

159. Changes in milliampere-seconds can a ect all the ollowing except (A) (B) (C) (D)

quantity o x-ray photons produced exposure rate receptor exposure spatial resolution

160. Low kilovoltage exposure actors usually are indicated or radiographic examinations using 1. water-soluble, iodinated media 2. a negative contrast agent 3. barium sul ate (A) (B) (C) (D)

1 only 1 and 2 only 3 only 1 and 3 only

161. Which o the ollowing examinations might require the use o 70 kV? 1. AP abdomen 2. Chest radiograph 3. Barium- lled stomach (A) (B) (C) (D)

1 only 2 only 1 and 2 only 2 and 3 only

162. Which o the ollowing is are associated with magni cation uoroscopy? 1. Increased mA 2. Smaller portion o the input phosphor is used 3. Image intensi er ocal point moves closer to the output phosphor (A) (B) (C) (D)

Figure 4-20. From the American College of Radiology Learning File. Courtesy of the ACR.

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

202

4: Image Acquisition and Evaluation

163. A lateral SF projection o the lumbar spine was made using 200 mA, 1.0-second exposure, and 90 kV. I the exposure actors were changed to 200 mA, 0.5 second, and 104 kV, there would be an obvious change in which o the ollowing? 1. Receptor exposure 2. Scale o radiographic contrast 3. Distortion (A) (B) (C) (D)

1 only 2 only 2 and 3 only 1, 2, and 3

164. Subject object unsharpness can result rom all o the ollowing except when (A) object shape does not coincide with the shape o x-ray beam (B) object plane is not parallel with x-ray tube and or IR (C) anatomic object(s) o interest is are in the path o the CR (D) anatomic object(s) o interest is are a distance rom the IR

167. A decrease rom 200 to 100 mA will result in a decrease in which o the ollowing? 1. Wavelength 2. Exposure rate 3. Beam intensity (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

168. T e radiograph shown in Figure 4-21 illustrates incorrect use o (A) (B) (C) (D)

collimator grid AEC ocal spot

165. Brightness and contrast resolution in digital imaging can be in uenced by 1. window level (WL) 2. window width (WW) 3. look-up table (LU ) (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

166. What eature is used to display RIS in ormation on current patients? (A) (B) (C) (D)

HIS Modality work list PACS DICOM

Figure 4-21. Courtesy of Stamford Hospital, Department of Radiology.

169. T e e ect described as di erential absorption is 1. responsible or radiographic contrast 2. a result o attenuating characteristics o tissue 3. minimized by the use o a high peak kilovoltage (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

Questions: 163–177

170. A satis actory radiograph o the abdomen was made at a 38-in SID using 400 mA, 60-ms exposure, and 80 kV. I the distance is changed to 42 in, what new exposure time would be required? (A) (B) (C) (D)

25 ms 50 ms 73 ms 93 ms

171. Which o the ollowing is (are) associated with subject contrast? 1. Patient thickness 2. issue density 3. Kilovoltage (A) (B) (C) (D) 172.

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

203

175. Why is a very short exposure time essential in chest radiography? (A) (B) (C) (D)

o avoid excessive ocal-spot blur o maintain short-scale contrast o minimize involuntary motion o minimize patient discom ort

176. T e interaction between x-ray photons and matter illustrated in Figure 4-22 is most likely to be associated with 1. high kilovoltage 2. high contrast 3. high–atomic-number absorber (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

ypical patient demographic and examination in ormation include(s) 1. type o examination 2. accession number 3. date and time o examination (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

173. For which o the ollowing examinations might the use o a grid not be necessary in an adult patient? (A) (B) (C) (D)

Hip Knee Abdomen Lumbar spine

174. T e quantity o scattered radiation reaching the IR can be reduced through the use o 1. a ast imaging system 2. an air gap 3. a stationary grid (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

Figure 4-22.

177. Beam attenuation characteristics, or density values, in C are expressed as 1. Houns eld units 2. C numbers 3. heat units (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

204

4: Image Acquisition and Evaluation

178. I an IR exposed using a 12:1 ratio grid exhibits loss o signal at its lateral edges, it is probably because the (A) SID was too great (B) grid ailed to move during the exposure (C) x-ray tube was angled in the direction o the lead strips (D) central ray was o -center 179. Which o the ollowing is (are) characteristic(s) o a 5:1 grid? 1. It allows some positioning latitude. 2. It is used with high kilovoltage exposures. 3. It absorbs a high percentage o scattered radiation. (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 1, 2, and 3

180. How is SID related to exposure rate and image receptor exposure? (A) As SID increases, exposure rate increases and receptor exposure increases. (B) As SID increases, exposure rate increases and receptor exposure decreases. (C) As SID increases, exposure rate decreases and receptor exposure increases. (D) As SID increases, exposure rate decreases and receptor exposure decreases. 181. A x-ray exposure o a particular part is made and restricted to a 14 × 17 in eld size. T e same exposure is repeated, but the x-ray beam is restricted to a 4 × 4 in eld. Compared with the rst image, the second image is likely to 1. generate less scattered radiation 2. require increased exposure actors 3. demonstrate less spatial resolution (A) (B) (C) (D)

1 only 1 and 2 only 3 only 2 and 3 only

182. In digital imaging, F DEL size is related to (A) (B) (C) (D)

contrast brightness spatial resolution plate size

183. Which o the ollowing pathologic conditions would require an increase in exposure actors? (A) (B) (C) (D)

Pneumoperitoneum Obstructed bowel Renal colic Ascites

184. Factors that determine spatial resolution in digital imaging include 1. ocal-spot size 2. SID 3. DEL size (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

185. Which o the ollowing analog screen– lm technical changes would best serve to remedy the e ect o very dissimilar tissue densities? (A) (B) (C) (D)

Use o a small ocal spot Use o a high-ratio grid High kilovoltage exposure actors High milliampere-seconds exposure actors

186. A QA program serves to 1. keep patient dose to a minimum 2. keep radiographic quality consistent 3. ensure equipment e ciency (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

Questions: 178–192

187. One line pair is described as (A) two black lines on a light background (B) one blank line on a light background and an interspace o the same width (C) two black lines on a light background ollowed by two similar interspaces (D) black lines that are 5, 8, 12, or 16 times taller then their adjacent interspaces 188. Any images obtained using dual x-ray absorptiometry (DXA) bone densitometry 1. are used to evaluate accuracy o the region o interest (ROI). 2. are used as evaluation or various bone joint disorders. 3. re ect the similar attenuation properties o sof tissue and bone. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

205

191. A SF x-ray image made using 300 mA, 0.1 second, and 75 kV exhibits motion unsharpness but otherwise satis actory technical quality. T e image will be repeated using a shorter exposure time. Using 86 kV and 400 mA, what should be the new exposure time? (A) (B) (C) (D)

25 ms 37 ms 50 ms 75 ms

192. T e radiograph shown in Figure 4-23 was made using screen lm technique and exhibits an artiact caused by (A) (B) (C) (D)

an inverted ocused grid poor screen– lm contact a oreign body in the IR static electricity

189. Foreshortening o an anatomic structure means that (A) it is projected on the IR smaller than its actual size. (B) its image is more lengthened than its actual size. (C) it is accompanied by geometric blur. (D) it is signi cantly magni ed. 190. Digital radiographic imaging equipment provides a number o unctions or optimization o image quality, including 1. exposure data recognition 2. automatic rescaling 3. narrow latitude (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Figure 4-23. From the American College of Radiology Learning File. Courtesy of the ACR.

206

4: Image Acquisition and Evaluation

193. X-ray tubes used in C di er rom those used in x-ray, in that C x-ray tubes must 1. have a very high short-exposure rating 2. be capable o tolerating several million heat units 3. have a small ocal spot or optimal resolution (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

194. Figure 4-24 is representative o (A) (B) (C) (D)

the anode heel e ect the line- ocus principle the inverse square law the reciprocity law

196. When involuntary motion must be considered in SF imaging, the exposure time may be cut in hal i the kilovoltage is (A) (B) (C) (D)

doubled increased by 15% increased by 25% increased by 35%

197. Which o the ollowing groups o exposure actors would be most e ective in eliminating prominent pulmonary vascular markings in the RAO position o the sternum? (A) (B) (C) (D)

500 mA, 1/30 second, 70 kV 200 mA, 0.04 second, 80 kV 300 mA, 1/10 second, 80 kV 25 mA, 7/10 second, 70 kV

198. An exposure was made o a part using 300 mA and 0.06 second with a 200-speed screen- lm combination. An additional radiograph is requested using a 400-speed system to reduce motion unsharpness. Using 400 mA, all other actors remaining constant, what should be the new exposure time? (A) (B) (C) (D)

Figure 4-24.

195. Which o the ollowing can impact the visibility o the anode heel e ect? 1. SID 2. IR size 3. Focal-spot size (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

5 ms 11 ms 22 ms 44 ms

199. T e image seen in Figure 4-25 was made using screen- lm technique and the lm was processed in a chemical lm processor. T e arti acts seen on the resulting radiograph are called (A) (B) (C) (D)

pi lines guide-shoe marks hesitation marks reticulation

Questions: 193–206

207

202. I , upon QC testing, the HVL o the x-ray beam produced by a particular x-ray tube increases, it is an indication o 1. vaporized tungsten deposited on the inner surace o the glass envelope 2. an increase in the kilovoltage being produced by the tube 3. a decrease in the kilovoltage being produced by the tube (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

203. A compensating lter is used to (A) absorb the harm ul photons that contribute only to patient dose. (B) even out widely di ering tissue densities. (C) eliminate much o the scattered radiation. (D) improve uoroscopy. Figure 4-25. Courtesy of Stamford Hospital, Department of Radiology.

200. HVL is a ected by the amount o 1. kVp 2. beam ltration 3. tissue density (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

201. T e attenuation o x-ray photons is not in uenced by 1. pathology 2. structure atomic number 3. photon quantity (A) (B) (C) (D)

1 only 3 only 2 and 3 only 1, 2, and 3

204. Boxes o lm stored in too warm an area may be subject to (A) static marks (B) lm og (C) high contrast (D) loss o density 205. Which o the ollowing will in uence spatial resolution? 1. Dynamic range 2. Part motion 3. Focal spot (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

206. Which interaction is responsible or producing the most x-ray photons at the x-ray tube target? (A) (B) (C) (D)

Bremsstrahlung Characteristic Photoelectric Compton

208

4: Image Acquisition and Evaluation

207. Factors that determine the production o scattered radiation include 1. eld size 2. beam restriction 3. kilovoltage (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

208. Which o the ollowing is (are) classi ed as rare earth phosphors? 1. Lanthanum oxybromide 2. Gadolinium oxysul de 3. Cesium iodide (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

209. Which o the ollowing is the most appropriate critique or the image seen as Figure 4-26? (A) (B) (C) (D)

insu cient penetration low ratio no grid used poor detail excessive brightness

210. As grid ratio is decreased in analog SF imaging, (A) (B) (C) (D)

the scale o contrast becomes longer the scale o contrast becomes shorter receptor exposure decreases radiographic distortion decreases

211. X-ray lm emulsion is most sensitive to sa elight og (A) (B) (C) (D)

be ore exposure and development af er exposure during development at low humidity

212. Which o the ollowing ocal-spot sizes should be employed or magni cation radiography? (A) (B) (C) (D)

0.2 mm 0.6 mm 1.2 mm 2.0 mm

213. I a 6-inch OID is introduced during a particular radiographic examination, what change in SID will be necessary to overcome objectionable magni cation? (A) (B) (C) (D)

T T T T

e SID must be increased by 6 inches. e SID must be increased by 18 inches. e SID must be decreased by 6 inches. e SID must be increased by 42 inches.

214. I a particular grid has lead strips 0.40 mm thick, 4.0 mm high, and 0.25 mm apart, what is its grid ratio? (A) (B) (C) (D)

8:1 10:1 12:1 16:1

215. T e line- ocus principle expresses the relationship between

Figure 4-26.

(A) the actual and the e ective ocal spot (B) exposure given the IR and resulting receptor exposure (C) SID used and resulting receptor exposure (D) grid ratio and lines per inch

Questions: 207–224

216. Which o the ollowing has the greatest e ect on radiographic IR exposure? (A) (B) (C) (D)

Aluminum ltration Kilovoltage SID Scattered radiation

217. Shape distortion is in uenced by the relationship between the 1. x-ray tube and the part to be imaged 2. part to be imaged and the IR 3. IR and the x-ray tube (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

218. T e attened hemidiaphragms and widened intercostal spaces seen in Figure 4-27 are representative o (A) (B) (C) (D)

emphysema congestive heart ailure pneumonia pleural e usion

209

219. IRs requently have a rear lead- oil layer that unctions to (A) (B) (C) (D)

improve penetration absorb backscatter preserve resolution increase the screen speed

220. T e continued emission o light by a phosphor af er the activating source has ceased is termed (A) uorescence (B) phosphorescence (C) image intensi cation (D) quantum mottle 221. Which combination o exposure actors most likely will contribute to producing the shortest-scale contrast?

(A) (B) (C) (D)

mAs 10 12 15 20

kV 70 90 90 80

Screen–Film System 400 200 200 400

Grid Ratio 5:1 8:1 12:1 10:1

Field Size 14 × 17 inch 14 × 17 inch 11 × 14 inch 8 × 10 inch

222. How of en are radiographic equipment collimators required to be evaluated? (A) (B) (C) (D)

Annually Biannually Semiannually Quarterly

223. During CR imaging, the latent image present on the PSP is changed to a computerized image by the (A) (B) (C) (D)

PSP Scanner–reader ADC helium–neon laser

224. Exposed silver halide crystals are changed to black metallic silver by the

Figure 4-27. From the American College of Radiology Learning File. Courtesy of the ACR.

(A) (B) (C) (D)

preservative reducers activators hardener

210

4: Image Acquisition and Evaluation

225. Grid cuto due to o -centering would result in (A) overall loss o receptor exposure (B) both sides o the image receptor underexposed (C) overexposure under the anode end (D) underexposure under the anode end 226. T e advantage(s) o high kilovoltage chest radiography is (are) that 1. exposure latitude is increased 2. it produces long-scale contrast 3. it reduces patient dose (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

227. T e exposure actors o 400 mA, 70 ms, and 78 kV were used to produce a particular image receptor exposure. A similar image could be produced using 500 mA, 90 kV, and (A) (B) (C) (D)

14 ms 28 ms 56 ms 70 ms

228. Pathologic or abnormal conditions that would require a decrease in exposure actors include all o the ollowing except (A) (B) (C) (D)

osteoporosis osteomalacia emphysema pneumonia

229. T e arti act(s) seen in Figure 4-28 include 1. motion 2. jewelry arti acts 3. hair braid arti acts (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Figure 4-28.

230. Geometric unsharpness is directly in uenced by 1. OID 2. SOD 3. SID (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

231. Which o the ollowing is are associated with magni cation uoroscopy? 1. Less noise 2. Improved contrast resolution 3. Improved spatial resolution (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Questions: 225–239

232. Which o the ollowing may be used to reduce the e ect o scattered radiation on the radiographic image? 1. Grids 2. Collimators 3. Compression bands (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 1, 2, and 3

233. Which o the ollowing is (are) directly related to photon energy? 1. Kilovoltage 2. Milliamperes 3. Wavelength (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

234. What in ormation, located on each box o lm, is important to note and has a direct relationship to image quality? (A) (B) (C) (D)

Number o lms in the box Manu acturer’s name Expiration date Emulsion lot

235. I 40 mAs and a 200-speed screen– lm system were used or a particular exposure, what new milliampere-seconds value would be required to produce the same density i the screen– lm system were changed to 800 speed? (A) (B) (C) (D)

10 20 80 160

211

236. An exposure was made using 8 mAs and 60 kV. I the kilovoltage was changed to 70, what new milliampere-seconds value is required to maintain receptor exposure? (A) (B) (C) (D)

2 4 16 32

237. Methods that help to reduce the production o scattered radiation include using 1. compression 2. beam restriction 3. a grid (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

238. Compression o the breast during mammographic imaging improves the technical quality o the image because 1. geometric blurring is decreased 2. less scattered radiation is produced 3. patient motion is reduced (A) (B) (C) (D)

1 only 3 only 2 and 3 only 1, 2, and 3

239. Distortion can be caused by 1. tube angle 2. the position o the organ or structure within the body 3. the radiographic positioning o the part (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

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4: Image Acquisition and Evaluation

240. Which o the ollowing possesses the widest dynamic range? (A) (B) (C) (D)

Film screen imaging Beam restriction AEC CR

241. Which o the ollowing statements is (are) true with respect to the radiograph shown in Figure 4-29? 1. T e image exhibits long-scale contrast. 2. T e image exhibits a clothing arti act. 3. T e image demonstrates motion blur. (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

242. What is the relationship between tissue attenuation coe cient in C and its related Houns eld unit (HU)? (A) T e greater the tissue attenuation coe cient, the lower the HU value. (B) T e greater the tissue attenuation coe cient, the higher the HU value. (C) issue attenuation coe cient and HU value are unrelated. (D) issue attenuation coe cient and HU value are identical. 243. A grid usually is employed in which o the ollowing circumstances? 1. When radiographing a large or dense body part 2. When using high kilovoltage 3. When a lower patient dose is required (A) (B) (C) (D)

1 only 3 only 1 and 2 only 1, 2, and 3

244. Exposure actors o 90 kV and 3 mAs are used or a particular nongrid exposure. What should be the new milliampere-seconds (mAs) value i a 12:1 grid is added? (A) (B) (C) (D)

86 9 12 15

245. An exposure was made using 300 mA, 40 ms exposure, and 85 kV. Each o the ollowing changes will decrease the receptor exposure by one hal except a change to

Figure 4-29. Courtesy of Stamford Hospital, Department of Radiology.

(A) (B) (C) (D)

1

/50-second exposure 72 kV 10 mAs 150 mA

Questions: 240–248

246. Which o the ollowing is are true when comparing screen– lm imaging to CR imaging? 1. CR DQE is better than screen– lm DQE. 2. CR has a wider exposure range than screen– lm. 3. CR has better spatial resolution than screen– lm. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

247. Which o the ollowing is (are) methods used or x-ray lm silver reclamation? 1. Photoelectric method 2. Metallic replacement method 3. Electrolytic method (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

248. Which o the ollowing groups o technical actors would be most appropriate or the radiographic examination shown in Figure 4-30? (A) (B) (C) (D)

400 mA, 1/30 second, 72 kV 300 mA, 1/50 second, 82 kV 300 mA, 1/120 second, 94 kV 50 mA, 1/4 second, 72 kV

Figure 4-30. Courtesy of Stamford Hospital, Department of Radiology.

213

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4: Image Acquisition and Evaluation

249. In which o the ollowing examinations should 70 kV not be exceeded? (A) (B) (C) (D)

Upper GI (UGI) Barium enema (BE) Intravenous urogram (IVU) Chest

250. Which o the ollowing statements is (are) true regarding the arti act seen in the erect PA projection o the chest shown in Figure 4-31? (A) T e object is located within the patient. (B) T e object is located within the IP. (C) T e object is located between the patient and the x-ray tube. (D) T e object is located between the patient and the IP.

Figure 4-31. Courtesy of Stamford Hospital, Department of Radiology.

Answers and Explanations

1. (A) Shape distortion (e.g., oreshortening or elongation) is caused by improper alignment o the tube, part, and IR. Size distortion, or magni cation, is caused by too great an OID or too short an SID. Focal-spot blur is caused by the use o a large ocal spot. 2. (C) In SF imaging the density and contrast are determined principally by exposure actor selection. In digital imaging brightness and contrast are determined by computer sof ware and monitor controls…. however, the principal actor in good digital image visibility and patient dose is still the result o proper IR exposure. Selection o kV and mAs in digital imaging is very similar to SF imaging, that is, kV still a ects penetration, but not contrast; mAs still determines dose, but has no impact on brightness. T e terms density and brightness do not mean the same thing and there ore are not used interchangeably. 3. (A) Pixel depth is directly related to shades o gray – called dynamic range – and is measured in bits. T e greater the number o bits, the more shades o gray. For example, a 1-bit (21) pixel will demonstrate 2 shades o gray, whereas a 6-bit (26) pixel can display 64 shades, and a 7-bit (27) pixel 128 shades. However, pixel depth is unrelated to resolution. A digital image is ormed by a matrix o pixels (picture elements) in rows and columns. A matrix that has 512 pixels in each row and column is a 512 × 512 matrix. T e term eld o view is used to describe how much o the patient (e.g., 150-mm diameter) is included in the matrix. T e matrix and the eld o view can be changed independently

without one a ecting the other, but changes in either will change pixel size. As in traditional radiography, spatial resolution is measured in line pairs per millimeter (lp mm). As matrix size is increased (e.g., rom 512 × 512 to 1,024 × 1,024) there are more and smaller pixels in the matrix and, thereore, improved resolution. Fewer and larger pixels result in poor resolution, a “pixelly” image, that is, one in which you can actually see the individual pixel boxes. 4. (C) An algorithm is a series o computerized stepby-step instructions used to solve a problem. T e instructions are exible, that is, variable, and various options are checked to produce the best possible results rom the range o available options. Radiographically speaking, the algorithm will test a range o variations to produce the best possible group o exposure actors or the anatomic particular part and circumstances. 5. (B) T e image illustrates aliasing arti act, or Moiré e ect. Aliasing, or Moiré, has the appearance o somewhat wavy linear lines and can occur in computed radiography when using stationary grids. I the grid’s lead strip pattern (i.e., requency) matches the scanning (sampling) pattern o the scanner reader, the resulting inter erence can cause aliasing (also called Moiré) arti act. When sampling requencies are decreased, aliasing Moiré is less evident. As sampling requencies increase, aliasing Moiré is more obvious. 6. (B) As distance rom a light source increases, the light diverges and covers a larger area; the quantity

215

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o light available per unit area becomes less and less as distance increases. T e intensity (quantity) o light decreases according to the inverse square law, that is, the intensity o light at a particular distance rom its source is inversely proportional to the square o the distance. For example, i you decreased the distance between a book you were reading and your illuminating lamp rom 6 to 3 f , you would have our times as much light available. Similarly, SID has a signi cant impact on x-ray beam intensity. As the distance between the x-ray tube and IR increases, exposure rate decreases according to the inverse square law. 7. (C) Grids are composed o alternating strips o lead and radiolucent interspace material. T e interspace material is either aluminum or plastic ber. Aluminum resists moisture, is sturdier, provides a “smoother” appearance with less visible grid lines, but requires a higher mAs and there ore increases patient dose. Plastic ber interspace material can be a ected by moisture, resulting in warping. Carbon ber is of en used as image plate ront material because o its durability and homogeneity. 8. (C) Absorption occurs when an x-ray photon interacts with matter and disappears, as in the photoelectric e ect. Scattering occurs when there is partial trans er o energy to matter, as in the Compton e ect. T e reduction in the intensity o an x-ray beam as it passes through matter is called attenuation. 9. (A) One o the biggest advantages o CR DR is the latitude it o ers. T e characteristic curve o typical lm emulsion has a “range o correct exposure” limited by the toe and shoulder o the curve. In CR DR, there is a linear relationship between the exposure, given the PSP and its resulting luminescence, as it is scanned by the laser, as illustrated in the gure. T is a ords much greater exposure latitude; technical inaccuracies can be e ectively eliminated. Overexposure o up to 500% and underexposure o up to 80% are reported as recoverable, thus eliminating most retakes. T is surely a ords increased e ciency; however, this does not mean that images can be exposed arbitrarily. T e pro essional radiographer has a responsibility to keep dose reduction to a minimum. T e same exposure actors as screen– lm systems or less generally are recommended or CR DR.

10. (B) An increase in kilovoltage (photon energy) will result in a greater number (i.e., exposure rate) o scattered photons (Compton interaction). T ese scattered photons carry no use ul in ormation and contribute to radiation og. In analog (screen– lm) imaging, this would result in decreased lower radiographic contrast. 11. (D) A C imaging system has three component parts—a gantry, a computer, and an operating console. T e gantry component includes an x-ray tube, a detector array, a high voltage generator, a collimator assembly, and a patient couch with its motorized mechanism. Although the C x-ray tube is similar to direct-projection x-ray tubes, it has several special requirements. T e C x-ray tube must have a very high short-exposure rating and must be capable o tolerating several million heat units while still having a small ocal spot or optimal resolution. o help tolerate the very high production o heat units, the anode must be capable o high-speed rotation. T e x-ray tube produces a pulsed x-ray beam (1–5 ms) using up to about 1,000 mA. 12. (A) T e image shown is a double exposure. Note the ilia and lower pelvic structures. wo pelves are clearly identi able. Particularly noteworthy is how CR will “correct” the exposure values. T e image does not appear overexposed, but the superimposed abdominal images are unmistakably evident. An inverted IP would have imaged the rear panel o the IP—a large grid-like appearance. An incomplete erasure or image ading would show only a portion o the image—here we have the entire superimposed abdomen. 13. (A) I a lateral projection o the chest is being perormed on an asthenic patient and the outer photocells are selected incorrectly, it is likely that IR exposure will be decreased. T e part is thin, and the lateral cells have little no tissue superimposed on them. T ere ore, as soon as the lateral photocells detect radiation (which will be immediately), the exposure will be terminated, leaving the IR with insu cient exposure. 14. (C) Milliampere-seconds (mAs) is the technical actor that regulates receptor exposure. Using the equation milliamperage × time = mAs, determine each mAs: (A) = 5 mAs, (B) = 8 mAs, (C) = 28 mAs, (D) = 18 mAs. Group C will produce the greatest exposure to the image receptor.

Answers: 7–20

15. (C) Inside the IP is the photostimulable phosphor (PSP). T is PSP (or SPS—Storage Phosphor Screen), with its layer o europium-activated barium uorohalide, serves as the IR because it is exposed in the traditional manner and receives the latent image. T e PSP can store the latent image or several hours; af er about 8 hours, noticeable image ading will occur. Once the IP is placed into the CR processor (scanner or reader), the PSP plate is removed automatically. T e latent image on the PSP is changed to a mani est image as it is scanned by a narrow, high-intensity helium–neon laser to obtain the pixel data. As the PSP is scanned in the reader, it releases a violet light—a process re erred to as photostimulated luminescence (PSL). 16. (D) All the actor changes a ect spatial resolution, but ocal-spot size does not a ect magni cation. An increase in SID would decrease magni cation. Although a decrease in SID will increase magni cation, it does not have as signi cant an e ect as an increase in OID. In general, it requires an increase o 7 in SID to compensate or every inch o OID. 17. (B) Digital systems provide some type o exposure indicator to serve as a quality control and radiation sa ety tool, in an e ort to avoid “dose creep.” T e exposure indicator name varies according to manuacturer: an S (sensitivity) number, EI (exposure index), REX (reached exposure index), or other identi ying exposure index depending on the manu acturer used. T e manu acturer usually provides a chart identi ying the acceptable range the exposure indicator numbers should be within or various examination types. While in one manu acturer’s system a high S number is related to under exposure, a high EI number in another manu acturer’s system is related to over exposure—it is essential or radiographers to be knowledgeable about the various types o equipment they use. 18. (B) Manu acturers o x-ray equipment must ollow guidelines that state maximum x-ray output at speci c distances, total quantities o ltration, positive beam limitation, and other guidelines. Radiographers must practice sa e principles o operation; preventive maintenance and quality control (QC) checks must be per ormed at speci c intervals to ensure continued sa e equipment per ormance. Radiologic QC involves monitoring and regulating the variables associated with image production and patient care.

217

HVL testing provides beam quality in ormation that is di erent rom that obtained rom kV testing. HVL is de ned as the thickness o any absorber that will reduce x-ray beam intensity to one-hal its original value. It is determined by measuring the beam intensity without an absorber and then recording the intensity as successive millimeters o aluminum are added to the radiation eld. It is inf uenced by the type o recti cation, total ltration, and kV. An x-ray tube HVL should remain almost constant. I HVL decreases, it is an indication o a decrease in the actual kV. I the HVL increases, it indicates the deposition o vaporized tungsten on the inner sur ace o the glass envelope (as a result o tube aging) or an increase in the actual kV. 19. (C) T e exposed IP is placed into the CR scanner reader, where the PSP SPS is removed automatically. T e latent image appears as the PSP is scanned by a narrow, high-intensity helium–neon laser to obtain the pixel data. As the PSP plate is scanned in the CR reader, it releases a violet light—a process re erred to as photostimulated luminescence (PSL). T e luminescent light is converted to electrical energy representing the analog image. T e electrical energy is sent to an analog-to-digital converter (ADC), where it is digitized and becomes the digital image that is displayed eventually (af er a short delay) on a high-resolution monitor and or printed out by a laser printer. T e digitized images can also be manipulated in postprocessing, transmitted electronically, and stored archived. 20. (D) he lateral projection o the coccyx seen in the igure is markedly overexposed. Although a small ocal spot would not be a practical selection or a lateral coccyx, ocal-spot size is unrelated to receptor exposure or contrast. I insu icient backup time had been selected, the image might be underexposed. he center photocell is the appropriate photocell to select because the part o interest, the coccyx, should be in the center o the image. Because the coccyx was not centered to the IR (but rather the thicker hip portion o the body was centered), the AEC correctly exposed the thicker portion—thus overexposing the less dense coccyx area. Accurate positioning centering is particularly important when using AEC.

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4: Image Acquisition and Evaluation

21. (B) Resolution describes how closely ne details may be associated and still be recognized as separate details be ore seeming to blend into each other and appear “as one.” T e degree o resolution trans erred to the IR is a unction o the resolving power o each o the system components and can be expressed in line pairs per millimeter (lp mm), line-spread unction (LSP), or modulation trans er unction (M F). Lp mm can be measured using a resolution test pattern; a number o resolution test tools are available. LSP is measured using a 10-mm x-ray beam; M F measures the amount o in ormation lost between the object and the IR. T e e ective ocal spot is the oreshortened size o the actual ocal spot as it is projected down toward the IR, that is, as it would be seen looking up into the emerging x-ray beam. T is is called the line- ocus principle and is not a unit used to express resolution. 22. (B) In electronic imaging (CR DR), the radiographer can manipulate the digital image displayed on the CR through postprocessing. One way to alter image contrast and or brightness is through windowing. T is re ers to some change made to window width and or window level. Change in window width changes the number o gray shades, that is, contrast scale/contrast resolution. Change in window level changes the image brightness. Windowing and other postprocessing mechanisms permit the radiographer to produce “special e ects” such as edge enhancement, image stitching, and image inversion, rotation, and reversal. A digital image is ormed by a matrix o pixels in rows and columns. A matrix having 512 pixels in each row and column is a 512 × 512 matrix. T e term eld o view is used to describe how much o the patient (e.g., 150-mm diameter) is included in the matrix. T e matrix or eld o view can be changed without a ecting the other, but changes in either will change pixel size. Automatic brightness control is associated with image intensi cation. 23. (A) Aligning the x-ray tube, anatomic part, and IR so that they are parallel reduces shape distortion. Angulation o the long axis o the part with respect to the IR results in oreshortening o the object. ube angulation causes elongation o the part. Size distortion (magni cation) is inversely proportional to SID and directly proportional to OID. Decreasing the SID and increasing the OID serve to increase size distortion.

24. (D) T e shortest possible exposure time should be used to minimize motion unsharpness. Motion causes unsharpness that destroys detail. Care ul and accurate patient instruction is essential or minimizing voluntary motion. Suspended respiration eliminates respiratory motion. Using the shortest possible exposure time is essential or decreasing involuntary motion. Immobilization is also very use ul in eliminating motion unsharpness. 25. (A) When the variable-kilovoltage method is used, a particular milliampere-seconds value is assigned to each body part. As part thickness increases, the kilovoltage (i.e., penetration) is also increased. T e body part being radiographed must be measured care ully, and or each centimeter o increase in thickness, 2 kV is added to the exposure. 26. (B) Boxes o x-ray lm, especially the larger sizes, should be stored in the vertical (upright) position. I lm boxes are stacked on one another, the sensitive emulsion can be a ected by pressure rom the boxes above. Pressure marks are produced and result in loss o contrast in that area o the radiographic image. When retrieving x-ray lm rom storage, the oldest should be used rst. 27. (C) Digital image postprocessing provides the opportunity or image optimization. Image annotation permits placement o labels, arrow indicators, etc. Windowing allows adjustment o image contrast and or brightness to diagnostic requirements. Contrast scale enhancement is the most valuable tool in digital imaging. Image mini cation, with larger matrix sizes, enables us to see tiny anatomic details and improve spatial resolution. Image inversion, or reversal, provides a di erent perspective by changing white to black and black to white. Image ip also provides another perspective by enabling us to rotate the image. Edge enhancement is use ul or small and high-contrast tissues. Other postprocessing unctions include highlighting, zoom, pan, and scroll. T e pixel shif eature is important in DSA. Image subtraction is used to enhance contrast. I the part moves during acquisition o serial images, misregistration occurs, making the required exact superimposition impossible. Pixel shif is a unction that can correct misregistration. Another emerging postprocessing task used in diagnostic unctions is determining numeric pixel value or particular

Answers: 21–34

ROI (region o interest). T is eature has proved use ul in bone densitometry, renal calculus recognition, and calci ed lung nodule identi cation. 28. (D) Film age is an important consideration when determining the causes o lm og. Outdated lm will exhibit loss o contrast in the orm o og and loss o speed. A sa elight is “sa e” only or practical periods o time required or the necessary handling o lm. Films that are lef out on the darkroom counter can be ogged by excessive exposure to the sa elight. Film emulsion is much more sensitive to sa elight og af er exposure. T e high temperatures required or automatic processors’ rapid processing are a source o lm og. Daily QA ensures that og levels do not exceed the upper limit o 0.2 density. 29. (A) As kilovoltage is increased, more high-energy photons are produced, and the overall energy o the primary beam is increased. Photon energy is inversely related to wavelength; that is, as photon energy increases, wavelength decreases. An increase in milliamperage serves to increase the number o photons produced at the target but is unrelated to their energy. 30. (B) O the two radiographs illustrated, image A was made recumbent, and image B was made in the erect position; this may be discerned by the presence o clearly de ned air– uid levels in the lower abdomen. Abdominal viscera move to a lower position in the erect position, making the abdomen “thicker” and requiring an increase in exposure (usually the equivalent o about 10 kV).

Inte rs pa ce ma te ria l

219

Le a d s trips

D

H

W grid ra tio = H:D

Figure 4-32.

distance between the strips), the higher the grid ratio, and the greater the percentage o scattered radiation absorbed. However, a grid does absorb some primary use ul radiation as well. T e higher the lead strips, the more critical is the need or accurate centering because the lead strips will more readily trap photons whose direction does not parallel them.

31. (D) Whereas CR uses traditional x-ray devices to enclose and protect the PSP SPS, digital radiography (DR) requires the use o somewhat di erent equipment. DR does not use cassettes or a traditional x-ray table; it is a direct-capture system o x-ray imaging. DR uses solid-state detector plates as the x-ray IR (instead o a cassette in the Bucky tray) to intercept the collimated x-ray beam and orm the latent image. T e solid-state detector plates are made o barium uorohalide compounds similar to that used in CR’s PSP SPSs. DR a ords the advantage o immediate display o the image, compared with CR’s delayed image display.

33. (C) As kilovoltage is increased, more electrons are driven to the anode with greater speed and energy. More high-energy electrons will result in production o more high-energy, more penetrating x-rays. T us, kilovoltage a ects both quantity and quality (energy) o the x-ray beam. However, although kilovoltage and receptor exposure are directly related, they are not directly proportional; that is, twice the receptor exposure does not result rom doubling the kilovoltage. With respect to the e ect o kilovoltage on receptor exposure, i it is desired to double the exposure to the IR yet impossible to adjust the milliampere-seconds, a similar e ect can be achieved by increasing the kilovoltage by 15%. Conversely, the receptor exposure may be cut in hal by decreasing the kilovoltage by 15%. T ere ore, a decrease in kilovoltage will produce ewer x-ray photons, resulting in decreased exposure to the IR. Kilovoltage is unrelated to spatial resolution.

32. (C) Grid ratio is de ned as the height o the lead strips to the width o the interspace material (Fig. 4-32). T e higher the lead strips (or the smaller the

34. (B) T e image shown is the result o using a CR image plate inadvertently upside down. T e rear panel is imaged, showing a large grid-like pattern. A

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double exposure would have demonstrated superimposed anatomical images (see Fig. 4-3). An incomplete erasure or image ading would show only a portion o the anatomical image—here, we see the entire anatomical part. 35. (D) Phosphors that have a high atomic number are more likely to absorb a high percentage o the incident x-ray photons and convert x-ray photon energy to uorescent light energy. How e ciently the phosphors detect and interact with the x-ray photons is termed quantum detection e ciency. How e ectively the phosphors make this energy conversion is termed conversion e ciency. 36. (C) Spatial resolution in CR is impacted by the size o the PSP, the size o the scanning laser beam, and monitor matrix size. High-resolution monitors (2–4 MP, megapixels) are required or high-quality, high-resolution image display. T e larger the matrix size, the better is the image resolution. ypical image matrix size (rows and columns) used in chest radiography is 2,048 × 2,048. As in traditional radiography, spatial resolution is measured in line pairs per millimeter. As matrix size is increased, there are more and smaller pixels in the matrix and, there ore, improved spatial resolution. Other actors contributing to image resolution are the size o the laser beam and the size o the PSP phosphors. Smaller phosphor size improves resolution in ways similar to that o intensi ying screens—anything that causes an increase in light di usion will result in a decrease in resolution. Smaller phosphors in the PSP (SPS) plate allow less light di usion. In addition, the scanning laser light must be o the correct intensity and size. A narrow laser beam is required or optimal resolution. 37. (B) In digital imaging, pixel size is determined by dividing the eld o view (FOV) by the matrix. In this case, the FOV is 20 cm; since the answer is expressed in millimeters, rst change 20 cm to 200 mm. T en 200 divided by 512 equals 0.39 mm: 20 cm = 200 mm 200 ÷ 512 = 0.39 mm pixel T e FOV and matrix size are independent o one another; that is, either can be changed, and the other will remain una ected. However, pixel size is a ected by changes in either the FOV or matrix size. For example, i the matrix size is increased, pixel size

decreases. I FOV is increased, pixel size increases. Pixel size is inversely related to resolution. As pixel size increases, resolution decreases. 38. (A) One way to minimize scattered radiation reaching the IR is to use optimal kilovoltage; excessive kilovoltage increases the production o scattered radiation. Close collimation is exceedingly important because the smaller the volume o irradiated material, the less scattered radiation will be produced. T e mAs selection has no impact on scattered radiation production or cleanup. Low-ratio grids allow a greater percentage o scattered radiation to reach the IR. Use o a high-ratio grid will clean up a greater amount o scattered radiation be ore it reaches the IR. Use o a compression band, or the prone position, in a large abdomen has the e ect o making the abdomen “thinner”; it will, there ore, generate less scattered radiation. 39. (D) Grid ratio is de ned as the ratio o the height o the lead strips to the width o the interspace material; the higher the lead strips, the more scattered radiation they will trap and the greater is the grid’s e ciency. T e greater the number o lead strips per inch, the thinner and less visible they will be on the nished radiograph. T e unction o a grid is to absorb scattered radiation in order to improve radiographic contrast. T e selectivity o a grid is determined by the amount o primary radiation transmitted through the grid divided by the amount o scattered radiation transmitted through the grid. 40. (C) T e radiographer can manipulate (i.e., change or enhance) digital images displayed on the CR through postprocessing. One way to alter image contrast and or brightness is through windowing. T e term windowing re ers to some change made to window width and or window level. Change in window width a ects change in the number o gray shades, that is, image contrast—as demonstrated in the gures shown (Fig. 4-7). Change in window level a ects change in the image brightness. Windowing and other postprocessing mechanisms permit the radiographer to e ect changes in the image and to produce “special e ects” such as edge enhancement, image stitching (use ul in scoliosis examinations), image inversion, rotation, and reversal. 41. (D) Exposure rate is regulated by milliamperage. Distance signi cantly a ects the exposure rate

Answers: 35–47

according to the inverse square law o radiation. Kilovoltage also has an e ect on exposure rate because an increase in kilovoltage will increase the number o high-energy photons produced at the target. T e size o the x-ray eld determines the volume o tissue irradiated, and hence the amount o scattered radiation generated, but is unrelated to the exposure rate. 42. (C) Spatial resolution is evaluated by how sharply tiny anatomic details are imaged on the radiograph. T e area o blurriness that may be associated with small image details is termed geometric blur. T e blurriness can be produced by using a large ocal spot or by di used uorescent light rom intensi ying screens. T e image proper (i.e., without blur) is termed the umbra. Mottle is a grainy appearance caused by ast imaging systems. 43. (B) Radiographiccontrast is de ned as the degree o di erence between adjacent densities. T ese tissue density di erences represent sometimes very subtle di erences in the absorbing properties o adjacent body tissues. T e radiographic subject, the patient, is composed o many di erent tissue types that have varying densities, resulting in varying degrees o photon attenuation and absorption. T e atomic number o the tissues under investigation is directly related to their attenuation coe cient. T is di erential absorption contributes to the various shades o gray (scale o radiographic contrast) on the nished analog screen– lm radiograph. Normal tissue density may be altered signi cantly in the presence o pathologic processes. T e technical actor used to regulate SF contrast is kilovoltage. Radiographic contrast is unrelated to milliampere-seconds. 44. (C) Grid ratio is de ned as the height o the lead strips compared with (divided by) the width o the interspace material. T e width o the lead strips has no bearing on the grid ratio. T e height o the lead strips is 5 mm; the width o the interspace material (same as the distance between the lead strips) is 0.5 mm. T ere ore, the grid ratio is 5 0.5, or a 10:1 grid ratio. 45. (B) Magni cation is part o every radiographic image. Anatomic parts within the body are at various distances rom the IR and, there ore, have various degrees o magni cation. T e ormula

221

used to determine the amount o image magni cation is Image size SID = Object size SOD Substituting known values: 44 in ( SID ) x = 5 in 38 in (SOD ) (SOD = SID-OID) 38x = 220 T us, x = 5.78-in image width. 46. (C) T e higher the kilovoltage range, the greater is the exposure latitude (margin o error in exposure). Higher kilovoltage produces more energetic photons, is more penetrating, and produces more grays on the analog radiographic image, lengthening the scale o contrast. As kilovoltage increases, the percentage o scattered radiation also increases (in both analog and digital imaging). 47. (D) Digital image storage is located in a pixel, which is a two-dimensional “picture element,” measured in the “XY” direction. T e third dimension, “Z” direction, in the matrix o pixels is the depth that is re erred to as the voxel (volume element). T e depth o the block is the number o bits required to describe the gray level that each pixel can take on—known as the bit depth. Bit depth in C is approximately 212 with a dynamic range o almost 5,000 gray shades, approximately 214 in CR DR with a dynamic range o more than 16,000 gray shades, and approximately 216 in digital mammography with a dynamic range o more than 65,500 gray shades. T e matrix is the number o pixels in the XY direction. As matrix size increases, or a xed FOV, pixel size is smaller and better spatial resolution results. An electronic digital image is ormed by a matrix o pixels in rows and columns. A matrix having 512 pixels in each row and column is a 512 × 512 matrix (a typical C image). T e term FOV is used to describe how much o the patient is included in the matrix. Either the matrix or the FOV can be changed without one a ecting the other, but changes in either will change pixel size. As FOV increases, or a xed matrix size, the size o each pixel increases and spatial resolution decreases. Fewer and larger pixels result in a poor-resolution “pixelly” or “mosaicked”

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image, that is, one in which you can actually see the individual pixel boxes. 48. (C) Focal-spot size accuracyis related to the degree o geometric blur, that is, edge gradient or penumbra. Manu acturer tolerance or new ocal spots is 50%; that is, a 0.3-mm ocal spot actually may be 0.45 mm. In addition, the ocal spot can increase in size as the x-ray tube ages—hence the importance o testing newly arrived ocal spots and periodic testing to monitor ocal-spot changes. Focal-spot size can be measured with a pinhole camera, slit camera, or star-pattern-type resolution device. T e pinhole camera is rather di cult to use accurately and requires the use o excessive tube (heat) loading. With a slit camera, two exposures are made; one measures the length o the ocal spot, and the other measures the width. T e star pattern, or similar resolution device such as the bar pattern, can measure ocalspot size as a unction o geometric blur and is readily adaptable in a QA program to monitor ocal-spot changes over a period o time. It is recommended that ocal-spot size be checked on installation o a new x-ray tube and annually thereaf er. 49. (A) I the SID is above or below the recommended ocusing distance, the primary beam will not coincide with the angled lead strips at their lateral edges. Consequently, there will be absorption o the primary beam termed grid cuto . I the central ray is o -center longitudinally, there will be no ill e ects. I the central ray is o -center side to side, the lead strips are no longer parallel with the divergent x-ray beam, and there will be loss o receptor exposure owing to grid cuto . Central ray angulation in the direction o the lead strips is appropriate and will not cause grid cuto . Central ray angulation against the direction o the lead strips will cause grid cuto . 50. (C) T e tiny areas o increased brightness, termed dropout arti acts, and seen in the proximal portion o the CR image o the radius shown are representative o dust/dirt particles that have accumulated on the PSP. PSPs (as well as any other re ective surace) are susceptible to dust, and can appear as little clear pinholes. PSPs are particularly sensitive to scattered radiation og and backscatter, but these would give the image the typical overall gray

appearance o og. Phantom image arti acts are a result o incomplete erasure o a previous image on that PSP. Image ading occurs i an exposed PSP has been lef several hours without processing and usually a ects the entire image. 51. (B) Use o a short SID with a large-size IR (and also with anode angles o 10 degrees or less) causes the anode heel e ect to be much more apparent. T e x-ray beam needs to diverge more to cover a large-size IR, and it needs to diverge even more or coverage as the SID decreases. T e x-ray beam has no problem diverging toward the cathode end o the beam, but as it tries to diverge toward the anode end o the beam, it is eventually stopped by the anode (x-ray photons are absorbed by the anode). T is causes a decrease in beam intensity at the anode end o the beam and is characteristic o the anode heel e ect. 52. (D) Each milliampere-second setting is determined [(A) = 4; (B) = 4; (C) = 8; (D) = 2] and numbered in order o greatest to least density [(C) = 1; (A) and (B) = 2; (D) = 3]. T en, the kilovoltages are reviewed and also numbered in order o greatest to least density [(A), (B), and (C) = 1; (D) = 2]. Next, screen speeds are numbered rom greatest density-producing to least density-producing [(D) and (B) = 1; (A) = 2; (C) = 3]. Finally, the numbers assigned to the milliampere-seconds, kilovoltage, and screen speed are added up or each o the our groups [(B) = 4; (A) and (C) = 5; (D) = 6]; the lowest total (B) indicates the group o actors that will produce the greatest radiographic density; the highest total (D) indicates the group o actors that will produce the least radiographic density. T is process is illustrated as ollows: (A) (B) (C) (D)

4 mAs (2) + 4 mAs (2) + 8 mAs (1) + 2 mAs (3) +

94 kV (1) + 94 kV (1) + 94 kV (1) + 80 kV (2) +

100 screens (2) = 5 200 screens (1) = 4 50 screens (3) = 5 200 screens (1) = 6

53. (D) I developer temperature is too high, some o the less exposed or unexposed silver halide crystals may be reduced, thus creating chemical og. I the developer solution has become oxidized rom exposure to air, chemical og also results. I developer replenishment is excessive, and too much new solution is replacing the deteriorated developer, chemical og is again the result.

Answers: 48–59

54. (C) Because the anode’s ocal track is beveled (angled, acing the cathode), x-ray photons can reely diverge toward the cathode end o the x-ray tube. However, the “heel” o the ocal track prevents x-ray photons rom diverging toward the anode end o the tube. T is results in varying intensity rom anode to cathode, with ewer photons at the anode end and more photons at the cathode end. T e anode heel e ect is most noticeable when using large IRs, short SIDs, and steep target angles. 55. (A) While CR utilizes traditional x-ray tables and IPs to enclose and protect the exible PSP screen, DR requires the use o signi cantly di erent equipment. DR does not use IPs or a traditional x-ray table—it is a direct-capture conversion, or indirectcapture conversion, system o x-ray imaging. Besides eliminating IPs and their handling, DR a ords the advantage o immediate display o the image (compared with CR’s slightly delayed image display), and DR exposures can be lower because o the detector’s higher DQE (i.e., ability to perceive and interact with x-ray photons). DR, like CR, also o ers the advantage o image preview and postprocessing. 56. (D) Digital image storage is located in a pixel, which is a two-dimensional “picture element,” measured in the “XY” direction. T e third dimension, “Z” direction, in the matrix o pixels is the depth that is re erred to as the voxel (volume element). T e depth o the block is the number o bits required to describe the gray level that each pixel can take on—known as the bit depth. Bit depth in C is approximately 212 with a dynamic range o almost 5,000 gray shades, approximately 214 in CR DR with a dynamic range o more than 16,000 gray shades, and approximately 216 in digital mammography with a dynamic range o more than 65,500 gray shades. T e matrix is the number o pixels in the XY direction. As matrix size increases, or a xed FOV, pixel size is smaller and better spatial resolution results. An electronic digital image is ormed by a matrix o pixels in rows and columns. A matrix having 512 pixels in each row and column is a 512 × 512 matrix (a typical C image). T e term FOV is used to describe how much o the patient is included in the matrix. Either the matrix or the FOV can be changed without one a ecting the other, but changes in either will change pixel size. As FOV increases, or a xed

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matrix size, the size o each pixel increases and spatial resolution decreases. Fewer and larger pixels result in a poor-resolution “pixelly” or “mosaicked” image, that is, one in which you can actually see the individual pixel boxes. 57. (D) Magni cation radiography may be used to delineate a suspected hairline racture or to enlarge tiny, contrast- lled blood vessels. It also has application in mammography. o magni y an object to twice its actual size, the part must be placed midway between the ocal spot and the IR. 58. (C) o change nongrid exposures to grid exposures, or to adjust exposure when changing rom one grid ratio to another, you must remember the actor or each grid ratio: No grid = 5:1 grid = 6:1 grid = 8:1 grid = 12:1 grid = 16:1 grid =

1× 2× 3× 4× 5× 6×

original mAs original mAs original mAs original mAs original mAs original mAs

o adjust exposure actors, you simply compare the old with the new: 12 (old mAs) 6 (old grid factor) = x (new mAs) 4 (new grid factor) 6x = 48 x = 88 mAs (using 8:1 grid) 59. (A) One type o indirect-capture at-panel detector uses cesium iodide or gadolinium oxysul de as the scintillator, that is, which captures x-ray photons and emits light. T at light is then trans erred via a photodetector coupling agent—a CCD or F . In direct-capture at-panel detector systems, x-ray energy is converted to an electrical signal in a single layer o material such as the semiconductor a-Se. Electric charges are applied to both sur aces o the a-Se, electron–hole pairs are created, and charges are read by F arrays located on the suraces. T e electrical signal is trans erred directly to the ADC. T e number o F s is equal to the number o image pixels. T us, the direct-capture system eliminates the scintillator step required in indirect DR. Since selenium has a relatively low Z number (compared with gadolinium [Z 64] or cesium [Z 55]), a-Se

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detectors are made thicker to improve detection, thus compensating or the low x-ray absorption o selenium. T ere is no di usion o electrons, so spatial resolution is not a ected in this manner. 60. (A) Digital Imaging (CR DR) is the same as SF (or projection) imaging with respect to the production o x-rays, x-ray interaction and production o scatter, x-ray beam geometry, and actors a ecting resolution detail and distortion. Digital imaging di ers rom SF imaging in its method o acquisition; in a one (direct conversion) or two (indirect conversion) step process, remnant x-ray photons are converted into an electric charge image. Computer hardware and sof ware are required in both CR and DR. Analog-to-digital conversion is required in CR; that conversion is the second step in the two-step process. 61. (D) T e PSP plate within the CR image plate has several layers. Its uppermost layer is a protective coat or the phosphor layer below. T is layer a ords durability and must be translucent to allow passage o photostimulable luminescent light. T e phosphor layer is the “active” layer that responds to the x-ray photons that reach it. Under the phosphor layer is the electroconductive layer that serves to acilitate transportation through the scanner reader and prevent image arti acts resulting rom static electricity. Below the electroconductive layer is the plate support layer. Below the support layer is a light-shield layer that serves to prevent light rom erasing image plate data or rom approaching through the rear protective layer. Behind the light-shield layer is the rear protective layer o the PSP plate. 62. (B) Field o view (FOV) re ers to the area being viewed. T e FOV can be increased or decreased. As the FOV is increased, the part being examined is magni ed; as the FOV is decreased, the part returns closer to actual size. Pixel size is a ected by changes in either the FOV or matrix size. For example, i the matrix size is increased, or example, rom 256 × 256 to 512 × 512, pixel size must decrease. I FOV increases, pixel size must increase. Pixel size is inversely related to resolution. As pixel size decreases, resolution increases. 63. (C) I a airly large patient is turned prone, the abdominal measurement will be signi cantly di erent rom the AP measurement as a result o the

e ect o compression. T us, the part is essentially “thinner,” and less scattered radiation will be produced. I the patient remains supine and a compression band is applied, a similar e ect will be produced. Beam restriction is probably the single most e ective means o reducing the production o scattered radiation. Grid ratio a ects the cleanup o scattered radiation; it has no e ect on the production o scattered radiation. 64. (B) wo screen– lm images o the skull are shown and their appearance is quite di erent. Image A demonstrates higher shorter scale contrast. Image B is quite gray—demonstrating low- long-scale contrast. Image B would have higher contrast i a higher-ratio grid had been used. T e positioning o the images is identical; no motion or distortion is apparent. 65. (C) Grids are used in radiography to absorb scattered radiation be ore it reaches the IR (grid “cleanup”), thus improving radiographic contrast. Contrast obtained with a grid compared with contrast without a grid is termed contrast-improvement actor. T e greater the percentage o scattered radiation absorbed compared with absorbed primary radiation, the greater is the “selectivity” o the grid. I a grid absorbs an abnormally large amount o use ul radiation as a result o improper centering, tube angle, or tube distance, grid cuto occurs. 66. (D) Digital image storage is located in a pixel, a two-dimensional “picture element,” measured in the “XY” direction. T e third dimension, “Z” direction, in the matrix o pixels is the depth—re erred to as the voxel (volume element). T e depth o the block is the number o bits required to describe the gray level that each pixel can take on—known as bit depth. Bit depth in C is about 212 with a dynamic range o almost 5,000 gray shades, about 214 in CR/ DR with a dynamic range o more than 16,000 gray shades, and about 216 in digital mammography with a dynamic range o more than 65,500 gray shades. T e matrix is the number o pixels in the XY direction. As matrix size increases, or a xed FOV, pixel size is smaller and better image resolution results. An electronic digital image is ormed by a matrix o pixels in rows and columns. A matrix having 512 pixels in each row and column is a 512 × 512 matrix (a typical C image). T e term FOV is used to describe how much o the patient is included in the matrix. Either the matrix or the FOV can be

Answers: 60–72

changed without one a ecting the other, but changes in either will change pixel size. As FOV increases, or a xed matrix size, the size o each pixel increases and spatial resolution decreases. Fewer and larger pixels result in a poor-resolution “pixelly” (“mosaicked”) image, that is, one in which you can actually see the individual pixel boxes. In the gure shown, Image #1 is the most pixelly mosaicked, having a matrix o 16 × 16, and demonstrates the poorest spatial resolution. T e images improve with Image #2 having a matrix o 32 × 32, Image #3 having a matrix 64 × 64, and Image #4 having a matrix o 128 × 128—and the best spatial resolution. An image matrix o 256 × 256 would demonstrate even better resolution. 67. (C) Size distortion (magni cation) is inversely proportional to SID and directly proportional to OID. Increasing the SID and decreasing the OID decrease size distortion. Aligning the tube, part, and IR so that they are parallel reduces shape distortion. T ere are two types o shape distortion—elongation and oreshortening. Angulation o the part with relation to the IR results in oreshortening o the object. ube angulation causes elongation o the object. 68. (D) Digital image storage is located in a pixel, which is a two-dimensional “picture element,” measured in the “XY” direction. T e third dimension, “Z” direction, in the matrix o pixels is the depth that is re erred to as the voxel (volume element). T e depth o the block is the number o bits required to describe the gray level that each pixel can take on—known as the bit depth. T e matrix is the number o pixels in the XY direction. As matrix size increases, or a xed FOV, pixel size is smaller and better spatial resolution results. An electronic digital image is ormed by a matrix o pixels in rows and columns. A matrix having 512 pixels in each row and column is a 512 × 512 matrix (a typical C image). T e term FOV is used to describe how much o the patient is included in the matrix. Either the matrix or the FOV can be changed without one a ecting the other, but changes in either will change pixel size. As FOV increases, or a xed matrix size, the size o each pixel increases and spatial resolution decreases. Fewer and larger pixels result in a poor-resolution “pixelly” or “mosaicked” image, that is, one in which you can actually see the individual pixel boxes.

225

69. (C) T e FOV and matrix size are independent o one another; that is, either can be changed, and the other will remain una ected. However, pixel size is a ected by changes in either the FOV or matrix size. For example, i the matrix size is increased, pixel size decreases. I FOV increases, pixel size increases. Pixel size is inversely related to resolution. As pixel size decreases, resolution increases. 70. (A) T e ocal-spot size selected will determine the amount o ocal spot, or geometric, blur produced in the image. OID and SID are responsible or image magni cation and hence spatial resolution. T e milliamperage is unrelated to spatial resolution; it a ects only the quantity o x-ray photons produced and thus the receptor exposure. 71. (B) According to the exposure-maintenance ormula, i the SID is changed to 42 in, 16.33 mAs is required to maintain the original receptor exposure: (old mAs) 12 (old D 2 ) 362 = (New mAs) x (new D 2 ) 422 12 1,296 = x 1,764 1,296x = 21,168 T us, x = 16.33 mAs at 42 in SID. T en, to compensate or changing rom a 12:1 grid to a 5:1 grid, the milliampere-seconds value becomes 6.53 mAs: (old mAs) 16.33 (old grid factor) 5 = (New mAs) x (old grid factor) 2 5x = 32.66 T us, x = 6.53 mAs with 5:1 grid at 42 in SID. Hence, 6.53 mAs is required to produce a receptor exposure similar to that o the original radiograph. T e ollowing are the actors used or milliampereseconds conversion rom nongrid to grid: No grid = 5:1 grid = 6:1 grid = 8:1 grid = 12:1 grid = 16:1 grid =

1× 2× 3× 4× 5× 6×

original mAs original mAs original mAs original mAs original mAs original mAs

72. (C) T e ormula mA × s = 5 mAs is used to determine each milliampere-second setting (remember to rst change milliseconds to seconds). T e greatest analog screen– lm radiographic density will be produced by the combination o highest

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milliampere-seconds value and shortest SID. T e groups in choices (B) and (D) should produce identical radiographic density, according to the inverse square law, because group (D) includes twice the distance and 4 times the milliampere-seconds value o group (B). T e group in (A) has twice the distance o the group in (B) but only twice the milliampere-seconds; there ore, it has the least density. T e group in (C) has the same distance as the group in (B) and twice the milliampere-seconds, making group in (C) the group o technical actors that will produce the greatest analog screen– lm radiographic density. In digital imaging, predetermined algorithm selections control the required contrast and brightness requirements. 73. (B) O the given actors, kilovoltage and grid ratio will have a signi cant e ect on analog screen– lm radiographic contrast. Remember that the milliampere-seconds value has no e ect on contrast scale. Because a combination o lower kilovoltage and a higher-ratio grid will allow the least amount o scattered radiation to reach the IR, thereby producing ewer gray tones, (B) is the best answer. (D) also uses low kilovoltage, but the grid ratio is lower—allowing more scatter to reach the IR (there ore, longer-scale contrast). In digital imaging, predetermined algorithm selections control the required contrast and brightness requirements. 74. (B) In digital imaging brightness and contrast are determined by computer sof ware and monitor controls…. however, the principal actor in good digital image visibility and patient dose is still the result o proper IR exposure. Selection o kV and mAs in digital imaging is very similar to SF imaging, that is, kV still a ects penetration, but not contrast; mAs still determines dose, but has no impact on brightness. Window level adjustments are associated with image brightness changes; window width adjustments are associated with changes in image contrast. T e terms density and brightness do not mean the same thing and there ore are not used interchangeably. 75. (B) In SF imaging the density and contrast are determined principally by exposure actor selection. In digital imaging brightness and contrast are determined by computer sof ware and monitor controls…. however, the principal actor in good digital image visibility and patient dose is still the result o proper IR exposure. Selection o kV and mAs in

digital imaging is very similar to SF imaging, that is, kV still a ects penetration, but not contrast; mAs still determines dose, but has no impact on brightness. T e terms density and brightness do not mean the same thing and there ore are not used interchangeably. 76. (D) As photon energy (kV) increases, so does the production o scattered radiation. he greater the density o the irradiated tissues, the greater is the production o scattered radiation. As the size o the irradiated eld increases, there is an increase in the volume o tissue irradiated, and the percentage o scatter again increases. Beam restriction is the single most important way to limit the amount o scattered radiation produced. 77. (B) Milliampere-seconds (mAs) is directly related to x-ray intensity quantity. Exposure to the IR will be doubled when the milliampere-seconds is doubled. Although kilovoltage (kV) describes beam quality and penetration, it also in uences beam intensity, thereby having e ect on IR exposure. Receptor exposure will be doubled when the kV is increased by 15%. 78. (D) Focal-spot size a ects spatial resolution by its e ect on ocal-spot blur: T e larger the ocalspot size, the greater is the blur produced. Spatial resolution is a ected signi cantly by distance changes because o their e ect on magni cation. As SID increases and as OID decreases, magni cation decreases and spatial resolution increases. SOD is determined by subtracting OID rom SID. 79. (D) Each o the three is included in a good QA program. Beam alignment must be accurate to within 2% o the SID. Reproducibility means that repeated exposures at a given technique must provide consistent intensity. Linearity means that a given milliampere-second setting, using di erent milliampere stations with appropriate exposure-time adjustments, will provide consistent intensity. 80. (B) Focal-spot blur, or geometric blur, is caused by photons emerging rom a large ocal spot. T e actual ocal spot is always larger than the e ective (or projected) ocal spot, as illustrated by the line- ocus principle. In addition, the e ective ocal-spot size varies along the longitudinal tube

Answers: 73–88

axis, being greatest in size at the cathode end o the beam and smallest at the anode end o the beam. Because the projected ocal spot is greatest at the cathode end o the x-ray tube, geometric blur is also greatest at the corresponding part (cathode end) o the radiograph. 81. (B) T e milliampere-seconds value regulates the number o x-ray photons produced at the target and thus regulates patient dose. I the milliampere-seconds is doubled, dose is doubled; thereore, mAs and patient dose are directly proportional. 82. (B) T e image plate ront material must not attenuate the remnant beam yet must be sturdy enough to withstand daily use. Bakelite has long been used as the material or tabletops and IR ronts, but now it has been replaced largely by magnesium and carbon bers. Lead would not be a suitable material because it would absorb the remnant beam, and no image would be ormed. 83. (C) Emphysema is abnormal distension o the pulmonary alveoli (or tissue spaces) with air. T e presence o abnormal amounts o air makes a decrease rom normal exposure actors necessary to avoid excessive receptor exposure. Congestive heart ailure, pneumonia, and pleural e usion all involve abnormal amounts o uid in the chest and, thereore, would require an increase in exposure actors. 84. (B) A review o the problem reveals that three changes are being made: an increase in SID, a decrease in kV, and a change in exposure time (to be considered last). T e original mAs value was 9. T e decrease in kV requires us to double the mAs to 18 in order to maintain su cient exposure. Now, we must deal with the distance change. Using the exposure-maintenance ormula (and remembering that 18 is now the old milliampere-seconds value), we nd that the required new milliampere-seconds value at 42 inches is 22.

(Old mAs) 18 = (old D

2

) 362 (New mAs) x (new D 2 ) 402 1,296x = 28,800

T us, x = 22.22 mAs at 40-inch SID. Because milliamperage is unchanged, we must determine the exposure time that, when used with 300 mA, will yield 22 mAs.

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300x = 22 x = 0.07-s exposure 85. (B) I it is desired to reduce the exposure time or a particular radiograph, as it might be when radiographing patients who are unable to cooperate ully, the milliamperage must be increased su ciently to maintain the original milliampere-seconds value and thus correct IR exposure. A higher kilovoltage could be use ul because it would allow urther reduction o the milliampere-seconds (exposure time) according to the 15% rule. Changing grid ratio is unrelated to desired changes in exposure time. Use o a higher-ratio grid would only necessitate an increase in mAs and not likely a decrease in exposure time. 86. (D) With three-phase equipment, the voltage never drops to zero, and x-ray intensity is signi cantly greater. When changing rom single-phase to three-phase, six-pulse equipment, two-thirds o the original milliampere-seconds value is required to produce a radiograph with similar receptor exposure. When changing rom single-phase to threephase, 12-pulse equipment, only hal the original milliampere-seconds value is required. In this problem, we are changing rom three-phase, 12-pulse to single-phase equipment; there ore, the milliampereseconds value should be doubled ( rom 4 to 8 mAs). 87. (C) A grid is composed o alternate strips o lead and interspace material. T e lead strips serve to trap scattered radiation be ore it ogs the IR. T e interspace material must be radiolucent; plastic or sturdier aluminum usually is used. Cardboard was used in the past as interspace material, but it had the disadvantage o being a ected by humidity (moisture). 88. (D) T e radiograph shown is that o an adult PA erect chest. T e image is well positioned and exposed, but observe the braids o hair that extend past the neck and superimpose on the pulmonary apices. Braided hair should be pinned up or otherwise removed rom superimposition on thoracic structures. T e braided hair was imaged during the exposure o the PA chest and is, there ore, re erred to as an exposure arti act. Example o a scanner reader arti act is laser jitter, which results in an image distortion. It is important to inquire about or examine patients or materials that will image

228

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radiographically and cast unwanted densities over essential anatomy. 89. (B) Arti acts can be a result o exposure, handling, and storage, or processing. Exposure arti acts include motion, double exposure, and patient clothing jewelry—the e ects o these are seen as a result o the exposure. Handling and storage arti acts include ogged PSP, image ading, upside-down IP, damaged PSP—all these occur as a result o improper use or storage. Processing arti acts occur while the PSP is in the scanner reader and include skipped scan lines, laser jitter, etc. 90. (B) As the kilovoltage is increased, a greater number o electrons are driven across to the anode with greater orce. T ere ore, as energy conversion takes place at the anode, more high-energy (short-wavelength) photons are produced. However, because they are higher-energy photons, there will be less patient absorption. 91. (D) In digital imaging, as in screen– lm radiography, there are numerous tonal values that represent various tissue densities (i.e., x-ray attenuation properties), or example, bone, muscle, at, bloodlled organs, air gas, metal, contrast media, and pathologic processes. In CR, the CR scanner reader recognizes all these values and constructs a representative grayscale histogram o them, corresponding to the anatomic characteristics o the imaged part. T us, all PA chest histograms are similar, all lateral chest histograms are similar, all pelvis histograms are similar, etc. A histogram is a graphic representation o pixel value distribution. T e histogram is an analysis and graphic representation o all the densities rom the PSP screen, demonstrating the quantity o exposure, the number o pixels, and their value. Histograms are unique to each body part imaged. Histogram appearance and patient dose can be a ected by the radiographer’s knowledge and skill using digital imaging, in addition to their degree o accuracy in positioning and centering. Collimation is exceedingly important to avoid histogram analysis errors. Lack o adequate collimation can result in signals outside the anatomic area being included in the exposure data recognition histogram analysis. T is can result in a variety o histogram analysis errors including excessively light, dark, or noisy images. Poor collimation can a ect exposure level

1

2

3

4

Figure 4-33.

and exposure latitude; these changes are re ected in the images’ in ormational numbers (“S number,” “exposure index,” etc.). Other actors a ecting histogram appearance, and there ore these in ormational numbers, include selection o the correct processing algorithm (e.g., chest vs. emur vs. cervical spine), changes in scatter, source-to-image-receptor distance (SID), objectto-image-receptor distance (OID), and collimation— in short, anything that a ects scatter and or dose. 92. (C) During automatic processing (Fig. 4-33), radiographic lm is rst immersed in the developer solution, which unctions to reduce the exposed silver bromide crystals in the lm emulsion to black metallic silver (which constitutes the image). Next, the lm goes directly into the xer, which unctions to remove the unexposed silver bromide crystals rom the emulsion. T e lm then is transported to the wash tank, where chemicals are removed rom the lm, and then into the dryer section, where it is dried be ore leaving the processor. 93. (B) An increase in SID will help to decrease the e ect o excessive OID. For example, in the lateral projection o the cervical spine, there is normally a signi cant OID that would result in obvious magni cation at a 40-inch SID. T is e ect is decreased by the use o a 72-inch SID. However, especially with larger body parts, increased SID usually requires a signi cant increase in exposure actors. Focal-spot size and grid ratio are unrelated to magni cation.

Answers: 89–101

94. (B) T e addition o a grid will help to clean up the scattered radiation produced by higher kilovoltage, but the grid requires an adjustment o milliampereseconds. According to the grid conversion actors listed here, the addition o an 8:1 grid requires that the original milliampere-seconds be multiplied by a actor o 4: No grid = 5:1 grid = 6:1 grid = 8:1 grid = 12:1 (or 10:1) grid = 16:1 grid =

1× 2× 3× 4× 5× 6×

original mAs original mAs original mAs original mAs original mAs original mAs

T e original milliampere-seconds value is 1.2. T e ideal adjustment, there ore, requires a 4.8 mAs at 90 kV. Although 2.4 mAs with 100 kV (choice C), or 1.2 mAs with 110 kV (choice A), also might seem workable, an increase in kilovoltage would urther compromise contrast, nulli ying the e ect o the grid. In addition, kilovoltage exceeding 100 should not be used with an 8:1 grid. 95. (D) T e PA projection o the chest shown in the gure demonstrates aint visualization o the thoracic vertebrae through the heart—characteristic o adequate penetration. Many shades o gray are seen, illustrating a long scale o contrast. T e image is representative o having been exposed at the ideal milliampere-seconds and kilovoltage actors. en posterior ribs are seen; this illustrates adequate inspiration. 96. (A) Exposure rate decreases with an increase in SID according to the inverse square law o radiation. T e quantity o x-ray photons produced at the ocal spot is the unction o milliampere-seconds. T e quality (i.e., wavelength, penetration, and energy) o x-ray photons produced at the target is the unction o kilovoltage. T e kilovoltage also has an e ect on exposure rate because an increase in kilovoltage will increase the number o highenergy x-ray photons produced at the anode. 97. (B) Osteoporosis is a condition, of en seen in the elderly, marked by increased porosity and sof ening o bone. T e bones are much less dense, and thus a decrease in exposure is required. Osteomyelitis and osteochondritis are in ammatory conditions that usually have no e ect on bone density. Osteosclerosis is abnormal hardening o the bone, and an increase in exposure actors would be required.

229

98. (B) Electromagnetic radiation can be described as wave-like uctuations o electric and magnetic elds. T ere are many kinds o electromagnetic radiation; visible light, microwaves, and radio waves, as well as x-ray and gamma rays, are all part o the electromagnetic spectrum. All the electromagnetic radiations have the same velocity, that is, 3 × 108 m s (1,86,000 miles per second); however, they di er greatly in wavelength and requency. Wavelength re ers to the distance between two consecutive wave crests. Frequency re ers to the number o cycles per second; its unit o measurement is hertz (Hz), which is equal to 1 cycle per second. Frequency and wavelength are closely associated with the relative energy o electromagnetic radiations. More energetic radiations have shorter wavelength and higher requency. T e relationship among requency, wavelength, and energy is graphically illustrated in the electromagnetic spectrum. Some radiations are energetic enough to rearrang e atoms in materials through which they pass, and they can there ore be hazardous to living tissue. T ese radiations are called ionizing radiation because they have the energetic potential to break apart electrically neutral atoms, resulting in the production o negative and or positive ions. 99. (C) As kilovoltage is reduced, the number o high-energy photons produced at the target is reduced; there ore, a decrease in receptor exposure occurs. I a grid has been used improperly (o centered or out o ocal range), the lead strips will absorb excessive amounts o primary radiation, resulting in grid cuto and loss o receptor exposure. I the SID is inadequate (too short), an increase in IR exposure will occur. 100. (A) Limiting the size o the radiographic eld (irradiated area) serves to limit the amount o scattered radiation produced within the anatomic part. T ereore, as eld size decreases, scattered radiation production decreases, and image quality increases. Limiting the size o the radiographic eld is a very e ective means o reducing the quantity o non– in ormation-carrying scattered radiation ( og) produced, resulting in improved detail visibility. Limiting the size o the radiographic eld is also the most e ective means o patient radiation protection. 101. (A) A compensating lter is used when the part to be radiographed is o uneven thickness or density

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4: Image Acquisition and Evaluation

(in the chest, mediastinum vs. lungs). T e lter (made o aluminum or lead acrylic) is constructed in such a way that it will absorb much o the x-ray photons that would have exposed the low tissue density area while allowing the remaining x-ray photons to pass una ected to the high tissue density area. A collimator is used to decrease the production o scattered radiation by limiting the volume o tissue irradiated. T e grid unctions to trap scattered radiation be ore it reaches the IR, thus reducing scattered radiation og. Added ltration addresses patient protection, decreasing patient dose. 102. (A) Scattered radiation is produced as x-ray photons travel through matter, interact with atoms, and are scattered (change direction). I these scattered rays are energetic enough to exit the body, they will strike the IR rom all di erent angles. T ey, there ore, do not carry use ul in ormation and merely produce a at, gray (low-contrast) og over the image. Grid cuto increases contrast and is caused by an improper relationship between the x-ray tube and the grid, resulting in absorption o some o the use ul primary beam. 103. (C) Control o motion, both voluntary and involuntary, is an important part o radiography. Patients are unable to control certain types o motion, such as heart action, peristalsis, and muscle spasm. In these circumstances, it is essential to use the shortest possible exposure time in order to have a “stop action” e ect. 104. (C) Motion, voluntary or involuntary, is most detrimental to good spatial resolution. Even i all other actors are adjusted to maximize detail, i motion occurs during exposure, detail is lost. T e most important ways to reduce the possibility o motion are using the shortest possible exposure time, care ul patient instruction ( or suspended respiration), and adequate immobilization when necessary. Minimizing magni cation through the use o increased SID and decreased OID unctions to improve spatial resolution. 105. (B) X-ray lm processing consists o our parts: development, xing, wash, and dry. Developing agents change the exposed silver bromide crystals (latent image) to black metallic silver, thus producing a mani est image. T e xer solution removes

the unexposed silver bromide crystals rom the emulsion and hardens the gelatin emulsion, thus ensuring permanence o the radiograph. 106. (B) In SF imaging the density and contrast are determined principally by exposure actor selection. In digital imaging brightness and contrast are determined by computer sof ware and monitor controls….however, the principal actor in good digital image visibility and patient dose is still the result o proper IR exposure. Selection o kV and mAs in digital imaging is very similar to SF imaging, that is, kV still a ects penetration, but not contrast; mAs still determines dose, but has no impact on brightness. T e terms density and brightness do not mean the same thing and there ore are not used interchangeably. 107. (C) Quantum noise, or mottle, is a grainy appearance; it has a spotted or reckled appearance. It looks very similar to a low-resolution photograph image that has been enlarged. Low mAs and high kV actors are most likely to be the cause o quantum noise mottle. Grid cuto is absorption o the use ul beam by the grid and usually results in loss o signal and visibility o grid lines. T e anode heel e ect is most pronounced using short SIDs, large IRs, small anode angles, and imaging parts having uneven tissue densities; it is represented by a noticeable IR exposure di erence between the anode and cathode ends o the image. 108. (C) Kilovoltage and the HVL a ect both the quantity and the quality o the primary beam. T e principal qualitative actor or the primary beam is kilovoltage, but an increase in kilovoltage will also create an increase in the number o photons produced at the target. HVL is de ned as the amount o material necessary to decrease the intensity o the beam to one-hal its original value, thereby e ecting a change in both beam quality and quantity. T e milliampere-seconds value is adjusted to regulate the number o x-ray photons produced at the target. X-ray-beam quality is una ected by changes in milliampere-seconds. 109. (A) As the distance rom ocal spot to IR (SID) increases, so does spatial resolution. Because the part is being exposed by more perpendicular (less divergent) rays, less magni cation and blur are

Answers: 102–117

produced. Although the best spatial resolution is obtained using a long SID, the necessary increase in exposure actors and resulting increased patient exposure become a problem. An optimal 40-in SID is used or most radiography, with the major exception being chest examinations. 110. (A) T e shortest possible exposure should be used as a matter o routine. Parkinson disease is characterized by uncontrollable tremors, and the resulting unsharpness can destroy image resolution detail. A short exposure time is essential. T at can be achieved by increasing the mA or the kV—AEC will react with a shorted exposure time. SID and compensating ltration are unrelated to the problem and are not indicated here. 111. (D) Insu cient milliamperage and or exposure time will result in lack o receptor exposure (density, in SF imaging). Insu cient kilovoltage can result in underpenetration and excessive contrast. Insu cient SID, however, will result in increased exposure rate and overexposure to the IR (and the part). 112. (B) T e ormula or mAs is mA × s = mAs. Substituting known values: 0.05x = 30 x = 600 mA 113. (B) T e original milliampere-seconds value was 9 (300 mA × 0.03 second). Using the exposure-maintenance ormula, the new milliampere-seconds value must be determined or the distance change rom 40 to 44 in o the SID: old D ) 40 ( = ( new mAs) x ( new D ) 44 2

(old mAs)9

2

2 2

1,600x = 17,424 T us, x = 10.89 (11) mAs at 44-inch SID. T en, i 500 is the new milliamperage, we must determine what exposure time is required to achieve 8.1 mAs: 500 x = 11 T us, x = 0.022 second (22 ms) at 500 mA and 44-in SID.

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exposure the milliampere-seconds value now must be cut in hal ( rom 9 to 4.5 mAs) to compensate. Grids are used to absorb scattered radiation rom the remnant beam be ore it can contribute to the x-ray image. Because the grid removes scattered radiation (and some use ul photons as well) rom the beam, an increase in exposure actors is required. T e amount o increase depends on the grid ratio; the higher the grid ratio, the higher is the correction actor. T e correction actor or a 12:1 grid is 5; there ore, the milliampere-seconds value (4.5) is multiplied by 5 to arrive at the new required milliampere-seconds value (22.5). Using the milliampere-seconds equation mA × s = mAs, it is determined that 0.15 second will be required at 300 mA: 300x = 22.5 x = 0.075 s = 75 ms. 115. (C) Dual x-ray absorptiometry (DXA) imaging is used to evaluate bone mineral density (BMD). It is the most widely used method o bone densitometry— it is low-dose, precise, and uncomplicated to use per orm. DXA uses two photon energies—one or sof tissue and one or bone. Since bone is denser and attenuates x-ray photons more readily, photon attenuation is calculated to represent the degree o bone density. Bone densitometry DXA can be used to evaluate bone mineral content o the body, or part o it, to diagnose osteoporosis or to evaluate the e ectiveness o treatments or osteoporosis. 116. (B) T e ormula or magni cation actor (MF) = image size object size. In the stated problem, the anatomic measurement is 14.7 cm, and the magnication actor is known to be 1.2. Substituting the known actors in the appropriate equation: image size MF = object size 14.7 1.2 = x 14.7 x= 1.2 x = 12.25 cm (actual anatomic size).

114. (C) A 15% increase in kilovoltage was made, increasing the kilovoltage to 87 kV. Because the kilovoltage change e ectively doubles the receptor

117. (B) DXA imaging is used to evaluate bone mineral density (BMD). Bone densitometry (i.e., DXA) can

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4: Image Acquisition and Evaluation

be used to evaluate bone mineral content o the body, or part o it, to diagnose osteoporosis or to evaluate the e ectiveness o treatments or osteoporosis. It is the most widely used method o bone densitometry—it is low-dose, precise, and uncomplicated to use per orm. DXA uses two photon energies—one or sof tissue and one or bone. Since bone is denser and attenuates x-ray photons more readily, their attenuation is calculated to represent the degree o bone density. Sof tissue attenuation in ormation is not used to measure bone density. 118. (B) While CR utilizes traditional x-ray tables and IPs to enclose and protect the exible PSP screen, DR requires the use o signi cantly di erent equipment. DR does not use IPs or a traditional x-raytable—itisadirect-capture conversion,orindirectcapture conversion, system o x-ray imaging. Besides eliminating IPs and their handling, DR a ords the advantage o immediate display o the image (compared with CR’s slightly delayed image display), and DR exposures can be lower because o the detector’s higher DQE (i.e., ability to perceive and interact with x-ray photons). DR, like CR, also o ers the advantage o image preview and postprocessing. 119. (B) T e radiograph shown demonstrates a 1.5-in unexposed strip along the length o the IR. T is occurred because, although the patient was centered correctly to the collimator light and x-ray eld, the x-ray tube was not centered to the grid. I the patient was o -center, the entire image would be exposed, and the patient’s spine would be o center. Grid cuto would not appear as such a sharply delineated line but rather as gradually decreasing loss o reception exposure. 120. (B) T e digital images’ scale o contrast (contrast resolution) and brightness, can be changed electronically through leveling and windowing o the image. T e level control determines the midbrightness, whereas the window control determines the total number o grays (to the right and lef o the central midbrightness). Matrix and pixel sizes are related to (spatial) resolution o digital images. 121. (D) T e purpose o the thin layer o lead that is of en located in the rear portion o an IP is to absorb x-ray photons that strike the rear o the IP and bounce back toward the PSP, resulting in

scattered radiation og. T e thin layer o lead absorbs these x-ray photons and thus improves the radiographic image. 122. (C) T e PSP plate within the CR cassette IP has several layers. Its uppermost layer is a protective coat or the phosphor layer below. T is layer a ords durability and must be translucent to allow passage o photostimulable luminescent light. T e phosphor layer is the “active” layer that responds to the x-ray photons that reach it. Under the phosphor layer is the electroconductive layer that serves to acilitate transportation through the scanner reader and prevent image arti acts resulting rom static electricity. Below the electroconductive layer is the plate support layer. Below the support layer is a light-shield layer that serves to prevent light rom erasing image plate data or rom approaching through the rear protective layer. Behind the light-shield layer is the rear protective layer o the PSP plate. 123. (C) Quantum noise, or mottle, is a grainy appearance; it has a spotted or reckled appearance. It looks very similar to a low-resolution photograph image that has been enlarged. Low mAs and high kV actors are most likely to be the cause o quantum noise mottle. SID is unrelated to quantum noise. 124. (A) In digital imaging, pixel size is determined by dividing the FOV by the matrix. In this case, the FOV is 60 cm; since the answer is expressed in millimeters, rst change 60 cm to 600 mm. T en 600 divided by 2,048 equals 0.35 mm: 60 cm = 600 mm 600 = 0.29 mm 2,084 T e FOV and matrix size are independent o one another; that is, either can be changed, and the other will remain una ected. However, pixel size is a ected by changes in either the FOV or matrix size. For example, i the matrix size is increased, pixel size decreases. I FOV increases, pixel size increases. Pixel size is inversely related to resolution. As pixel size increases, resolution decreases. 125. (C) In electronic digital imaging, changes in window width a ect changes in contrast scale, while changes in window level a ect changes in

Answers: 118–130

brightness. As window width increases, the scale o contrast increases (i.e., contrast decreases). As window level increases, brightness increases. T is can be easily illustrated as you postprocess window your own digital photographs or scanned documents. As the brightness scale is moved in one direction or the other, images become more or less bright. 126. (D) T e matrix is the number o pixels in the xy direction. T e larger the matrix size, the better is the image resolution. ypical image matrix sizes used in radiography are • Nuclear medicine • Digital subtraction angiography (DSA) • C • Chest radiography

128 × 128 1,024 × 1,024 512 × 512 2,048 × 2,048

A digital image is ormed by a matrix o pixels in rows and columns. A matrix having 512 pixels in each row and column is a 512 × 512 matrix. T e term eld o view is used to describe how much o the patient (e.g., 150-mm diameter) is included in the matrix. T e matrix or eld o view can be changed without a ecting the other, but changes in either will change pixel size. As in traditional radiography, spatial resolution is measured in line pairs per millimeter (lp/mm). As matrix size is increased, there are more and smaller pixels in the matrix and, there ore, improved spatial resolution. Fewer and larger pixels result in a poor-resolution “pixelly” image, that is, one in which you can actually see the individual pixel boxes. 127. (C) Quality control in mammography includes scrupulous testing o virtually all component parts o the mammographic imaging system. It includes processor checks, screen maintenance, accurate and consistent viewing conditions, and evaluation o phantom images, to name a ew. T e device shown constitutes the structures to be imaged within a mammography phantom. A mammographic phantom contains Mylar bers, simulated masses, and specks o simulated calci cations. T e American College o Radiology accreditation criteria state that a minimum o 10 objects (4 bers, 3 specks, and 3 masses) must be visualized on test images. Changes in any part(s) o the imaging system (e.g., lm, screens, image receptors, x-ray equipment, ltration, or viewbox) can result in unsuccess ul results.

233

128. (D) Factors in uencing spatial resolution in digital imaging are very much the same as those actors a ecting recorded detail in analog imaging, that is, motion, geometric actors ( ocal-spot size, OID, and SID). In analog imaging, spatial resolution is related to the speed o the imaging system (intensi ying screen speed) and is signi cantly better than digital imaging resolution. T e spatial resolution o direct digital systems, however, is xed and is related to the detector element (DEL) size o the thin lm transistor ( F ). T e smaller the F DEL size, the better the spatial resolution. DEL size o 100 microns provides a spatial resolution o about 5 lp mm (available only in some digital mammography systems). DEL size o 200 microns provides a spatial resolution o about 2.5 lp mm (general radiography)—lower than that achieved with 400 speed intensi ying screen system. A 100 speed intensi ying screen system o ers a spatial resolution o about 10 lp mm—signi cantly greater than, and currently unachievable in, digital imaging. Spatial resolution in digital imaging is xed, but it is very important that radiographers are alert to the opportunity they have to utilize and control the remaining recorded detail actors (motion and geometric actors). 129. (D) Healthcare in ormation technology, or health in ormatics, has ever-increasing application and use in the imaging sciences. PACS (Picture Archiving and Communication Systems) is used by healthcare acilities to economically store, archive, exchange, and transmit digital images rom multiple imaging modalities. PACS replaces the need to manually le, retrieve, and transport lm and lm jackets. RIS (Radiology In ormation Systems) and HIS (Hospital In ormation Systems) can be integrated with PACS or electronic health in ormation storage. T e purpose o HIS is to manage healthcare in ormation and documents electronically, and to ensure data security and availability. RIS is a system or tracking radiological and imaging procedures. RIS is used or patient registration and scheduling, radiology work ow management, reporting and printout, manipulation and distribution and tracking o patient data, and billing. RIS complements HIS and is critical to competent work ow to radiologic acilities. 130. (B) o calculate milliampere-seconds, multiply milliamperage times exposure time. In this case,

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4: Image Acquisition and Evaluation

400 mA × 0.017 second (17 ms) = 6.8 mAs. Careul attention to proper decimal placement will help to avoid basic math errors. 131. (C) Externally, IPs (Image Plates) appear very much like traditional screen– lm cassettes. However, the main unction o an IP is to support and protect the PSP (SPS) that lies within the IP. IPs do not contain intensi ying screens or lm and, thereore, do not need to be lighttight. T e photostimulable PSP is not a ected by light. 132. (B) Radiographic technique charts are highly recommended or use with every x-ray unit. A technique chart identi es the standardized actors that should be used with that particular x-ray unit or various examinations positions o anatomic parts o di erent sizes. o be used e ectively, these technique charts require that the anatomic part in question be measured correctly with a caliper. A ulcrum is o importance in tomography; a densitometer is used in sensitometry and QA. 133. (A) Remnant x-rays emerging rom the patient part are converted to electrical signals. T is is an analog image. T ese electrical signals are sent to the ADC (analog-to-digital converter) to be converted to digital data (in binary digits or bits). T en, the digital image data is trans erred to a DAC (digital-to-analog converter) to be converted to a perceptible analog image on the display monitor. T e monitor image can be manipulated, postprocessed, stored, or transmitted. 134. (C) In digital imaging brightness and contrast are determined by computer sof ware and monitor controls…. however, the principal actor in good digital image visibility and patient dose is still the result o proper IR exposure. Selection o kV and mAs in digital imaging is very similar to SF imaging, that is, kV still a ects penetration, but not contrast; mAs still determines dose, but has no impact on brightness. Window level adjustments are associated with image brightness changes; window width adjustments are associated with changes in image contrast. T e terms density and brightness do not mean the same thing and thereore are not used interchangeably. 135. (B) T e heel e ect is characterized by a variation in beam intensity that increases gradually rom

anode to cathode. T is can be e ectively put to use when per orming radiographic examinations o large body parts with uneven tissue density. For example, the AP thoracic spine is thicker caudally than cranially, so the thicker portion is best placed under the cathode. However, in the lateral projection o the thoracic spine, the upper portion is thicker because o superimposed shoulders, and there ore, that portion is best placed under the cathode end o the beam. T e emur is also uneven in tissue density, particularly in the AP position, and can bene t rom use o the heel e ect. However, the sternum and its surrounding anatomy are airly uni orm in thickness and would not bene t rom use o the anode heel e ect. T e anode heel e ect is most pronounced when using large IRs at short SIDs and with an anode having a steep (small) target angle. 136. (D) As photon energy increases, more penetration and greater production o scattered radiation occur, producing a longer scale o contrast. As grid ratio increases, more scattered radiation is absorbed, producing a shorter scale o contrast. As OID increases, the distance between the part and the IR acts as a grid, and consequently, less scattered radiation reaches the IR, producing a shorter scale o contrast. Focal-spot size is related only to spatial resolution. 137. (D) T e lead strips in a parallel grid are parallel to one another and, there ore, are not parallel to the x-ray beam. T e more divergent the x-ray beam, the more likely there is to be cuto decreased receptor exposure at the lateral edges o the radiographic image. T is problem becomes more pronounced at short SIDs. A centering or tube angle problem would more likely be a noticeable receptor exposure loss on one side or the other. 138. (B) T is is an example o both o - ocus and lateral decentering errors. Note the asymmetric cuto rom right to lef . T e individual grid errors, as well as the result o both errors together, are summarized below. • O - ocus errors: Grid cuto will occur i the SID is below the lower limits, or above the upper limits, o the speci ed ocal range. T is type o error is also re erred to as ocus–grid distance decentering. O - ocus errors are usually characterized by loss o receptor exposure at the periphery o the image.

Answers: 131–146

• O -center errors: I the x-ray beam is not centered to the grid (i.e., i it is shif ed laterally) grid cuto will occur. T is type o error is re erred to as lateral decentering and characterized by a uniorm receptor exposure loss across the radiographic image. I the x-ray beam is both o -center and o - ocus below the ocusing distance, the portion o the image below the ocus will show increased receptor exposure; i the x-ray beam is o -center and o - ocus above the ocusing distance, the image below the ocus will show decreased receptor exposure. 139. (C) T e reciprocity law states that a particular milliampere-seconds value, regardless o the milliamperage and exposure time used, will provide identical radiographic receptor exposure. T is holds true with direct exposure techniques, but it does ail somewhat with the use o intensi ying screens. However, the ault is so slight as to be unimportant in most radiographic procedures. 140. (B) As the distance rom the object to the IR (OID) increases, so does magni cation distortion, thereby decreasing spatial resolution. Some magnication is inevitable in radiography because it is not possible to place anatomic structures directly on the IR. However, our understanding o how to minimize magni cation distortion is an important part o our everyday work. 141. (D) Milliampere-seconds (mAs) is the exposure actor that regulates receptor exposure. T e equation used to determine mAs is mA × s = mAs. Substituting the known actors: 300x = 6 x = 0.02 s (20 ms) 142. (C) Factors in uencing spatial resolution in digital imaging are very much the same as those actors a ecting recorded detail in analog imaging, that is, motion, geometric actors ( ocal-spot size, OID, and SID). In analog imaging, spatial resolution is related to the speed o the imaging system (intensi ying screen speed) and is signi cantly better than digital imaging resolution. T e spatial resolution o direct digital systems, however, is xed and is related to the detector element (DEL) size o the thin lm transistor ( F ). T e smaller the F DEL size, the better the spatial resolution. DEL size o 100 microns

235

provides a spatial resolution o about 5 lp mm (available only in some digital mammography systems). DEL size o 200 microns provides a spatial resolution o about 2.5 lp mm (general radiography)—lower than that achieved with 400 speed intensi ying screen system. A 100 speed intensi ying screen system o ers a spatial resolution o about 10 lp mm—signi cantly greater than, and currently unachievable in, digital imaging. Spatial resolution in digital imaging is xed, but it is very important that radiographers are alert to the opportunity they have to utilize and control the remaining recorded detail actors (motion and geometric actors). 143. (C) An increase in kilovoltage increases the overall average energy o the x-ray photons produced at the target, thus giving them greater penetrability. T is can also increase the incidence o Compton interaction and, there ore, the production o scattered radiation. Excessive scattered radiation reaching the IR will cause SR og noise. In digital imaging, predetermined algorithm selections control the required contrast and brightness requirements. 144. (A) Beam restrictors unction to limit the size o the irradiated eld. In so doing, they limit the volume o tissue irradiated (thereby decreasing the percentage o scattered radiation generated in the part) and help to reduce patient dose. Beam restrictors do not a ect the quality (energy) o the x-ray beam—that is, the unction o kilovoltage and ltration. Beam restrictors do not absorb scattered radiation—that is a unction o grids. 145. (C) SID is directly related to spatial resolution because as SID increases, so does spatial resolution (because magni cation is decreased). OID is inversely related to spatial resolution because as OID increases, spatial resolution decreases. Motion is also inversely related to spatial resolution because as motion increases, spatial resolution decreases—as a result o motion blur, the greatest enemy o resolution. T ereore, o the given choices, OID and motion are inversely related to spatial resolution. SID is directly related to spatial resolution. 146. (A) T e single most important actor regulating radiographic contrast in SF imaging is kilovoltage. T e lower the kilovoltage, the shorter is the scale o contrast. All the milliampere-seconds values in

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4: Image Acquisition and Evaluation

this problem have been adjusted or kilovoltage changes to maintain density, but just a glance at each o the kilovoltages is of en a good indicator o which will produce the longest scale or shortest scale contrast. 147. (A) T e arti act seen in the gure is a vertical processing arti act resulting rom irregular movement as PSP is removed rom the IP. A cleaning solution artiact usually appears as a splatter-like e ect. Secondary exposure results in ogging o the very sensitive PSP. Static electrical discharge is usually associated with screen– lm imaging. 148. (B) T e input phosphor o image intensi ers is usually made o cesium iodide. For each x-ray photon absorbed by cesium iodide, approximately 5,000 light photons are emitted. As the light photons strike a photoemissive photocathode, a number o electrons are released rom the photocathode and ocused toward the output side o the image tube by voltage applied to the negatively charged electrostatic ocusing lenses. T e electrons are then accelerated through the neck o the tube where they strike the small (0.5–1 in) output phosphor that is mounted on a at glass support. T e entire assembly is enclosed within a 2- to 4-mm thick vacuum glass envelope. Remember that the image on the output phosphor is mini ed, brighter, and inverted (electron ocusing causes image inversion). Input screen diameters o 5 to 12 in are available. Although smaller diameter input screens improve resolution, they do not permit a large FOV, that is, viewing o large patient areas.

149. (A) T e gure represents the anode heel e ect. Because the anode’s ocal track is beveled, x-ray photons can reely diverge toward the cathode end o the x-ray tube. However, the “heel” o the ocal track prevents x-ray photons rom diverging toward the anode end o the tube. T is results in varying intensity with ewer photons at the anode end (A) and more photons at the cathode end (B). T e line- ocus principle (Fig. 4-34) relates to the anode’s ocal spot, and x-ray tube targets are constructed according to the line- ocus principle—the ocal spot is angled to the vertical. As the actual ocal spot is projected downward, it is oreshortened; thus, Anode a ngle

Anode a ngle

e –– e– e– e Actua l foca l s pot X-ra y photons

Dual- and triple- eld image intensi ers are available that permit magni ed viewing o uoroscopic images. o achieve magni cation, the voltage to the ocusing lenses is increased and a smaller portion o the input phosphor is used, thereby resulting in a smaller FOV. Because mini cation gain is now decreased, the image is not as bright. T e mA is automatically increased to compensate or the loss in brightness when the image intensier is switched to magni cation mode. Entrance skin exposure (ESE) can increase dramatically as the FOV decreases (i.e., as magni cation increases). As FOV decreases, magni cation o the output screen image increases, there is less noise because increased mA provides a greater number o x-ray photons, and contrast and resolution improve. T e ocal point in the magni cation mode is urther away rom the output phosphor (as a result o increased voltage applied to the ocusing lenses) and there ore the output image is magni ed.

e– e– e– e–

Actua l foca l s pot

X-ra y photons Effe ctive foca l s pot

Effe ctive foca l s pot A

Ele ctrons

B

Figure 4-34. Reproduced with permission from Saia DA. Radiography PREP Program Review and Exam Preparation. 7th ed. New York, NY: McGraw-Hill; 2012.

Answers: 147–157

the e ective ocal spot is always smaller than the actual ocal spot. T e inverse square law deals with the changing x-ray intensity with changes in distance. T is principle is important in image ormation and in radiation protection. 150. (B) I (A) and (B) are reduced to 5 mAs or consistency, the kilovoltage will increase to 85 kV in both cases, thereby balancing radiographic receptor exposures. T us, the greatest receptor exposure is determined by the shortest SID (greatest exposure rate). 151. (B) Focal-spot size accuracy is related to the degree o geometric blur, that is, edge gradient or penumbra. Manu acturer tolerance or new ocal spots is 50%; that is, a 0.3-mm ocal spot actually may be 0.45 mm. In addition, the ocal spot can increase in size as the x-ray tube ages—hence, the importance o testing newly arrived ocal spots and periodic testing to monitor ocal-spot changes. Focal-spot size can be measured with a pinhole camera, slit camera, or star-pattern-type resolution device. T e pinhole camera is rather di cult to use accurately and requires the use o excessive tube (heat) loading. With a slit camera, two exposures are made; one measures the length o the ocal spot, and the other measures the width. T e star pattern, or similar resolution device, such as the bar pattern, can measure ocal-spot size as a unction o geometric blur and is readily adaptable in a QA program to monitor ocal-spot changes over a period o time. It is recommended that ocal-spot size be checked on installation o a new x-ray tube and annually thereaf er. 152. (D) Focusing distance is the term used to speci y the optimal SID used with a particular ocused grid. It is usually expressed as ocal range, indicating the minimum and maximum SID workable with that grid. Lesser or greater distances can result in grid cuto . Although proper distance is important in computed tomography and chest and magni cation radiography, ocusing distance is unrelated to them. 153. (B) T e radiographer selects a processing algorithm by selecting the anatomic part and particular projection on the computer control panel. T e CR unit then matches that in ormation with a

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particular lookup table (LU )—a characteristic curve that best matches the anatomic part being imaged. T e observer is able to review the image and, i desired, change its appearance (through “windowing”); doing so changes the LU . Hence, histogram analysis and use o the appropriate LU together unction to produce predictable image quality in CR. 154. (A) Grids are used in radiography to trap scattered radiation that otherwise would cause og on the radiograph. Grid ratio is de ned as the ratio o the height o the lead strips to the distance between them. Grid requency re ers to the number o lead strips per inch. Focusing distance and grid radius are terms denoting the distance range with which a ocused grid may be used. 155. (B) In the low kilovoltage ranges, a di erence o just a ew kilovolts makes a very noticeable radiographic di erence, there ore o ering little margin or error latitude. High kilovolt technical actors o er much greater margin or error; in the high kV ranges, an error o a ew kV makes little no di erence in the resulting image. Lower-ratio grids o er more tube-centering latitude than high-ratio grids. 156. (C) wo o a grid’s physical characteristics that determine its degree o e ciency in the removal o scattered radiation are grid ratio (the height o the lead strips compared with the distance between them) and the number o lead strips per inch. As the lead strips are made taller or the distance between them decreases, scattered radiation is more likely to be trapped be ore reaching the IR. A 12:1 ratio grid will absorb more scattered radiation than an 8:1 ratio grid. An undesirable but unavoidable characteristic o grids is that they do absorb some primary use ul photons as well as scattered photons. T e higher the ratio grid, the more scatter radiation the grid will clean up, but more use ul photons will be absorbed as well. T e higher the primary to scattered photon transmission ratio, the more desirable is the grid. Higher-ratio grids restrict positioning latitude more severely—grid centering must be more accurate (than with lower-ratio grids) to avoid grid cuto . 157. (D) In digital imaging, as in screen– lm radiography, there are numerous tonal values that represent various tissue densities (i.e., x-ray attenuation

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properties), or example, bone, muscle, at, bloodlled organs, air gas, metal, contrast media, and pathologic processes. In CR, the CR scanner reader recognizes these values and constructs a representative grayscale histogram o them, corresponding to the anatomic characteristics o the imaged part. T us, all PA chest histograms are similar, all lateral chest histograms are similar, all pelvis histograms are similar, etc. A histogram is a graphic representation o pixel value distribution. T e histogram is an analysis and graphic representation o all the densities rom the PSP screen, demonstrating the quantity o exposure, the number o pixels, and their value. Histograms are unique to each body part imaged. Histogram appearance and patient dose can be a ected by the radiographer’s knowledge and skill using digital imaging, in addition to their degree o accuracy in positioning and centering. Collimation is exceedingly important to avoid histogram analysis errors. Lack o adequate collimation can result in signals outside the anatomic area being included in the exposure data recognition histogram analysis. T is can result in a variety o histogram analysis errors including excessively light, dark, or noisy images. Poor collimation can a ect exposure level and exposure latitude; these changes are re ected in the images’ in ormational numbers (“S number,” “exposure index,” etc.). Other actors a ecting histogram appearance, and there ore these in ormational numbers, include selection o the correct processing algorithm (e.g., chest vs. emur vs. cervical spine), changes in scatter, source-to-image-receptor distance (SID), object-to-image-receptor distance (OID), and collimation—in short, anything that a ects scatter and or dose. 158. (C) T e screen lm radiographic image shown is an illustration o poor screen– lm contact. Motion and scattered radiation og can be ruled out because the blurriness is seen only in the apical region. Screen– lm contact is evaluated using a wire mesh that is placed on the questionable IR and radiographed (Fig. 4-35). Any areas o unsharpness represent poor contact, which can result rom warped screens, a oreign body in the IR, or a damaged IR rame. 159. (D) Milliampere-seconds (mAs) are the product o milliamperes (mA) and exposure time

Figure 4-35. From the American College of Radiology Learning File. Courtesy of the ACR.

(seconds). Any combinations o milliamperes and time that will produce a given milliampere-seconds value (i.e., a particular quantity o x-ray photons) will produce identical receptor exposure. T is is known as the reciprocity law. T e milliampere-seconds value is directly proportional to x-ray beam intensity, exposure rate, quantity, or number o x-ray photons produced and greatly impacts patient dose. I the milliampere-seconds value is doubled, twice the exposure rate, twice the patient dose, and twice the receptor exposure occur. I the milliampere-seconds value is cut in hal , the exposure rate, the patient dose, and receptor exposure are cut in hal . T e milliampereseconds value has no e ect on spatial resolution. 160. (B) Positive contrast medium is radiopaque; negative contrast material is radioparent. Barium sul ate (radiopaque, positive contrast material) is used most requently or examinations o the intestinal tract, and high kilovoltage exposure actors are used to penetrate (to see through and behind) the barium. Water-based iodinated contrast media (Conray, Amipaque) are also positive contrast agents. However, the K-edge binding energy o iodine prohibits the use o much greater than 70 kV

Answers: 158–164

with these materials. Higher kilovoltage values will obviate the e ect o the contrast agent. Air is an example o a negative contrast agent, and high kilovoltage actors are clearly not indicated.

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skin exposure (ESE) can increase dramatically as the FOV decreases (i.e., as magni cation increases). As FOV decreases, magni cation o the output screen image increases, there is less noise because increased mA provides a greater number o x-ray photons, and contrast and resolution improve. T e ocal point in the magni cation mode is urther away rom the output phosphor (as a result o increased voltage applied to the ocusing lenses) and there ore the output image is magni ed.

161. (A) It is appropriate to per orm an AP abdomen radiograph with lower kilovoltage because it has such low subject contrast. Abdominal tissue densities are so similar that it takes high- or short-scale contrast (using low kilovoltage) to emphasize the little di erence there is between tissues. However, high kilovoltage actors are used requently to even out densities in anatomic parts having high tissue contrast (e.g., the chest). However, since high kilovoltage produces added scattered radiation, it generally must be used with a grid. Barium- lled structures requently are radiographed using 120 kV or more to penetrate the barium—to see through to posterior structures

163. (B) T e original milliampere-seconds value (regulating receptor exposure) was 200. T e original kilovoltage (regulating radiographic contrast) was 90. T e milliampere-seconds value was cut in hal , to 100, causing a proportional decrease in receptor exposure. T e kilovoltage was increased (by 15%) to compensate or the receptor exposure loss and thereby increase the scale o contrast.

162. (B) T e input phosphor o image intensi ers is usually made o cesium iodide. For each x-ray photon absorbed by cesium iodide, approximately 5,000 light photons are emitted. As the light photons strike a photoemissive photocathode, a number o electrons are released rom the photocathode and ocused toward the output side o the image tube by voltage applied to the negatively charged electrostatic ocusing lenses. T e electrons are then accelerated through the neck o the tube where they strike the small (0.5–1 in) output phosphor that is mounted on a at glass support. T e entire assembly is enclosed within a 2- to 4-mm thick vacuum glass envelope. Remember that the image on the output phosphor is mini ed, brighter, and inverted (electron ocusing causes image inversion). Input screen diameters o 5 to 12 in are available. Although smaller diameter input screens improve resolution, they do not permit a large FOV, that is, viewing o large patient areas. Dual- and triple- eld image intensi ers are available that permit magni ed viewing o uoroscopic images. o achieve magni cation, the voltage to the ocusing lenses is increased and a smaller portion o the input phosphor is used, thereby resulting in a smaller FOV. Because mini cation gain is now decreased, the image is not as bright. T e mA is automatically increased to compensate or the loss in brightness when the image intensier is switched to magni cation mode. Entrance

164. (C) A certain amount o object unsharpness is an inherent part o every radiographic image because o the position and shape o anatomic structures within the body. Structures within the threedimensional human body lie in di erent planes. In addition, the three-dimensional shape o solid anatomic structures rarely coincides with the shape o the divergent beam. Consequently, some structures are imaged with more inherent distortion than others, and shapes o anatomic structures can be entirely misrepresented. Structures arther rom the IR will be distorted (i.e., magni ed) more than those closer to the IR; structures closer to the x-ray source will be distorted (i.e., magni ed) more than those arther rom the x-ray source. For the shape o anatomic structures to be accurately recorded, the structures must be parallel to the x-ray tube and the IR, and aligned with the central ray (CR). T e shape o anatomic structures lying at an angle within the body or placed away rom the CR will be misrepresented on the IR. T ere are two types o shape distortion. I a linear structure is angled within the body, that is, not parallel with the long axis o the part body and not parallel to the IR, that anatomic structure will appear smaller—it will be oreshortened. On the other hand, elongation occurs when the x-ray tube is angled. Image details placed away rom the path o the CR will be exposed by more divergent rays, resulting in rotation distortion. T is is why the CR must be directed to the part o greatest interest.

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Unless the edges o a three-dimensional object con orm to the shape o the x-ray beam, blur or unsharpness will occur at the partially attenuating edge o the object. T is can be accompanied by changes in receptor exposure, according to the thickness o areas traversed by the x-ray beam. 165. (D) T e radiographer selects a processing algorithm by selecting the anatomic part and particular projection on the computer control panel. T e CR unit then matches that in ormation with a particular lookup table (LU )—a characteristic curve that best matches the anatomic part being imaged. T e observer is able to review the image and, i desired, change its appearance (through “windowing”); doing so changes the LU . Histogram analysis and use o the appropriate LU together unction to produce predictable image quality in CR. In addition, the radiographer can manipulate, that is, change and enhance, the digital image displayed on the display monitor through postprocessing. One way to alter image contrast and or brightness is through windowing. T e term windowing re ers to some change made to window width and or window level, that is, a change in the LU . Change in window width a ects change in the number o gray shades, that is, image contrast. Change in window level a ects change in the image brightness. T ereore, windowing and other postprocessing mechanisms permit the radiographer to a ect changes in the image and produce “special e ects,” such as contrast enhancement, edge enhancement, image stitching. 166. (B) Patient demographic and examination in ormation originates rom the hospital acility HIS, where it is obtained when the patient is initially registered. T at in ormation is available or retrievable when the patient is scheduled, or arrives, or imaging services. ypical patient in ormation includes name, DOB or age, sex, ID number, accession number, examination being per ormed, date and time o examination. Additional in ormation may be available on the examination requisition; more in ormation is usually entered by the technologist at the time o the examination. A eature that is use ul in sorting examinations and decreasing (but not eliminating) errors is the Modality Work List (MWL). T e MWL “brings up” existing RIS in ormation, that is, the examinations

scheduled or each imaging area— or example, x-ray, C , MR, mammography, ultrasound, etc. T e technologist selects the correct patient, which includes that patient’s particular demographics, rom the particular modality work list. It is essential that the technologist is attentive to detail and accuracy when entering patient in ormation; errors in patient demographics entry, and entry duplication, must be avoided. PACS is used by healthcare acilities to economically store, archive, exchange, transmit digital images rom multiple imaging modalities; it replaces the need to manually le, retrieve, and transport lm and lm jackets. RIS and HIS can be integrated with PACS or electronic health in ormation storage. T e purpose o HIS is to manage healthcare in ormation and documents electronically, and to ensure data security and availability. RIS is a system or tracking radiological and imaging procedures. RIS is used or patient registration and scheduling, radiology work ow management, reporting and printout, manipulation and distribution and tracking o patient data, and billing. RIS complements HIS and is critical to competent work ow to radiologic acilities. 167. (C) echnical actors can be expressed in terms o milliampere-seconds rather than milliamperes and time. T e milliampere-seconds value is a quantitative actor because it regulates x-ray beam intensity, exposure rate, quantity, or number o x-ray photons produced (the milliampere-seconds value is the single most important technical actor associated with receptor exposure). T e milliampere-seconds value is directly proportional to the intensity (i.e., exposure rate, number, and quantity) o x-ray photons produced and the resulting receptor exposure. I the milliampere-seconds value is doubled, twice the exposure rate and twice the receptor exposure occur. I the milliampere-seconds value is cut in hal , the exposure rate and resulting receptor exposure are cut in hal . Kilovoltage is the qualitative exposure actor—it determines beam quality by regulating photon energy (i.e., wavelength). Kilovoltage has an e ect on receptor exposure, but it is not a proportional e ect. 168. (B) An upside-down ocused grid presents its lead strips in the opposite direction to that o the x-ray

Answers: 165–174

beam. T is results in severe grid cuto everywhere except in the central portion o the radiographic image. Severe grid cuto o chest anatomy can be seen outside the central exposed area. A misaligned collimator would not show such symmetrical loss o receptor exposure, nor would an incorrectly selected AEC photocell. Focal spot is unrelated to image receptor exposure. 169. (D) Di erential absorption re ers to the x-ray absorption characteristics o neighboring anatomic structures. T e radiographic representation o these structures is re erred to as radiographic contrast; it may be enhanced with high-contrast technical actors, especially using low kilovoltage levels. At low kilovoltage levels, the photoelectric e ect predominates. 170. (C) According to the inverse square law o radiation, as the distance between the radiation source and the IR decreases, the exposure rate increases. T ere ore, a decrease in technical actors is indicated. T e exposure-maintenance ormula is used to determine new milliampere-seconds values when changing distance:

(Old mAs) 24 = (old mAs D ) 38 2

2

(New mAs) x (new D 2 ) 422 24 1,444 = x 1,764 444 x = 42,336

T us, x = 29.31 mAs at 42-in SID. T en, to determine the new exposure time (mA × s = mAs), 400x = 29.31 T us, x = 0.073 second (73 ms) at 400 mA. 171. (D) Subject contrast has a signi cant in uence on radiographic contrast. Several actors in uence subject contrast, each as a result o beam-attenuation di erences in the irradiated tissues. As patient thickness and tissue density increase, attenuation increases, and subject contrast is increased. As kilovoltage increases, higher-energy photons are produced, beam attenuation is decreased, and subject contrast decreases. 172. (D) Patient demographic and examination in ormation originates rom the hospital acility HIS, where it is obtained when the patient is initially registered. T at in ormation is available or

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retrievable when the patient is scheduled, or arrives, or imaging services. ypical patient in ormation includes name, DOB or age, sex, ID number, accession number, examination being per ormed, date and time o examination. Additional in ormation may be available on the examination requisition; more in ormation is usually entered by the technologist at the time o the examination. A eature that is use ul in sorting examinations and decreasing (but not eliminating) errors is the Modality Work List (MWL). T e MWL “brings up” existing RIS in ormation, that is, the examinations scheduled or each imaging area— or example, x-ray, C , MR, mammography, ultrasound, etc. T e technologist selects the correct patient, which includes that patient’s particular demographics, rom the particular modality work list. It is essential that the technologist is attentive to detail and accuracy when entering patient in ormation; errors in patient demographics entry, and entry duplication, must be avoided. 173. (B) T e abdomen is a thick structure that contains many structures o similar density, and thus it requires increased exposure and a grid to absorb scattered radiation. T e lumbar spine and hip are also dense structures requiring increased exposure and use o a grid. T e knee, however, is requently small enough to be radiographed without a grid. T e general rule is that structures measuring more than 10 cm should be radiographed with a grid. 174. (C) Scattered radiation adds unwanted degrading densities to the x-ray image. T e single most important way to reduce the production o scattered radiation is to collimate. Although collimation, optimal kilovoltage, and compression can be used, a large amount o scattered radiation is still generated within the part being imaged, and because it adds unwanted non–in ormationcarrying densities, it can have a severely degrading e ect on image quality. A grid is a device interposed between the patient and IR that unctions to absorb a large percentage o scattered radiation be ore it reaches the IR. It is constructed o alternating strips o lead oil and radiolucent ller material. X-ray photons traveling in the same direction as the primary beam pass between the lead strips. X-ray photons, having undergone interactions within the body and deviated in various directions,

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are absorbed by the lead strips; this is re erred to as cleanup o scattered radiation. An air gap introduced between the object and IR can have an e ect similar to that o a grid. As energetic scattered radiation emerges rom the body, it continues to travel in its divergent ashion and much o the time will bypass the IR. It is usually necessary to increase the SID to reduce magni cation caused by increased OID. Imaging system speed is unrelated to scattered radiation. 175. (C) Radiographers usually are able to stop voluntary motion using suspended respiration, care ul instruction, and immobilization. However, involuntary motion also must be considered. o have a “stop action” e ect on the heart when radiographing the chest, it is essential to use a short exposure time. 176. (A) Diagnostic x-ray photons interact with tissue in a number o ways, but mostly they are involved in the production o Compton scatter or the photoelectric e ect. Compton scatter is pictured; it occurs when a relatively high-energy (kV) photon uses some o its energy to eject an outer-shell electron. In so doing, the photon is deviated in direction and becomes a scattered photon. Compton scatter causes objectionable scattered radiation og in large structures such as the abdomen and poses a radiation hazard to personnel during procedures such as uoroscopy. In the photoelectric e ect, a relatively low-energy x-ray photon uses all its energy to eject an inner-shell electron, leaving a hole in the K shell. An L-shell electron then drops down to ll the K vacancy and in so doing emits a characteristic ray whose energy is equal to the di erence between the binding energies o the K and L shells. T e photoelectric e ect occurs with high–atomicnumber absorbers such as bone and positive contrast media and is responsible or the production o radiographic contrast. It is help ul or the production o the radiographic image, but it contributes to the dose received by the patient (because it involves complete absorption o the incident photon). 177. (B) Sir God rey Newbold Houns eld created the rst C unit, describing the reconstruction o data taken rom multiple projection angles. Alan MacLeod Cormack worked with the complex mathematical algorithms required or image reconstruction. T eir rst commercial C head scanner was available in

1971. In 1979, Houns eld and Cormack shared the Nobel Prize in Medicine or their historic work with this new imaging science. o express the beam-attenuation characteristics o various tissues, the Houns eld unit (HU) is used. HUs can also be re erred to as C numbers or density values. God rey Houns eld assigned a value o 0 to distilled water, a value o + 1,000 to dense osseous tissue, and a value o –1,000 to air. T ere is a direct relationship between the HU and tissue attenuation coe cient. T e greater the attenuation coe cient o the particular tissue, the higher the HU value. One HU represents a 0.1% di erence between the particular tissue attenuation characteristics and that o distilled water. HU value accuracy can be a ected by equipment calibration, volume averaging, and image arti acts. 178. (A) T at portion o the x-ray beam striking the IR and representing image anatomy is re erred to as the signal. Some o the initial x-ray beam is absorbed via photoelectric interaction; some is scattered via Compton scatter (creating noise). I the SID is above or below the recommended ocusing distance, the use ul beam will not coincide with the angled lead strips at the lateral edges. Consequently, there will be absorption o the use ul beam, termed grid cuto , and diminished signal to the IR. I the grid ailed to move during the exposure, there would be grid lines throughout. Central ray angulation in the direction o the lead strips is appropriate and will not cause grid cuto . I the central ray were o -center, there would be uni orm loss o signal. 179. (A) Low-ratio grids, such as 5:1, 6:1, and 8:1, are used with moderate kilovolt techniques and are not recommended or use beyond 85 kV. T ey are not able to clean up the amount o scatter produced at high kilovoltages, but their low ratio permits more positioning latitude than high-ratio grids. High kilovoltage exposures produce large amounts o scattered radiation, and there ore, high-ratio grids are used in an e ort to trap more o this scattered radiation. However, accurate centering and positioning become more critical to avoid grid cuto . 180. (D) According to the inverse square law o radiation, the intensity or exposure rate o radiation is inversely proportional to the square o the distance rom its source. T us, as distance rom the source o radiation increases, exposure rate decreases.

Answers: 175–187

Because exposure rate and image receptor exposure are directly proportional, i the exposure rate o a beam directed to an IR is decreased, the resulting image receptor exposure would be decreased proportionately. 181. (B) Less scattered radiation is generated within a part as the kilovoltage is decreased, as the size o the eld is decreased, and as the thickness and density o tissue decrease. As the quantity o scattered radiation decreases rom any o these sources, overall receptor exposure will decrease and technical actors are likely to be increased. Spatial resolution is unrelated to eld size and scattered radiation. 182. (C) Factors in uencing spatial resolution in digital imaging are very much the same as those actors a ecting that is, motion, geometric in analog imaging, that is, motion, geometric actors ( ocalspot size, OID, and SID). T e spatial resolution o direct digital systems is xed and is related to the detector element (DEL) size o the thin lm transistor ( F ). T e smaller the F DEL size, the better the spatial resolution. DEL size o 100 microns provides a spatial resolution o about 5 lp mm (available only in some digital mammography systems). DEL size o 200 microns provides a spatial resolution o about 2.5 lp mm (general radiography)—lower than that achieved with 400 speed intensi ying screen system. A 100 speed intensi ying screen system o ers a spatial resolution o about 10 lp mm—signi cantly greater than, and currently unachievable in, digital imaging. Spatial resolution in digital imaging is xed, but it is very important that radiographers are alert to the opportunity they have to utilize and control the remaining recorded detail actors (motion and geometric actors). 183. (D) Because pneumoperitoneum is an abnormal accumulation o air or gas in the peritoneal cavity, it would require a decrease in exposure actors. Obstructed bowel usually involves distended, air- or gas- lled bowel loops, again requiring a decrease in exposure actors. With ascites, there is an abnormal accumulation o f uid in the abdominal cavity, necessitating an increase in exposure actors. Renal colic is the pain associated with the passage o renal calculi; no change rom the normal exposure actors is usually required.

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184. (D) Factors in uencing spatial resolution in digital imaging are very much the same as those actors a ecting recorded detail in analog imaging, that is, motion, geometric actors ( ocal-spot size, OID, and SID). In analog imaging, spatial resolution is related to the speed o the imaging system (intensiying screen speed) and is signi cantly better than digital imaging resolution. T e spatial resolution o direct digital systems, however, is xed and is related to the detector element (DEL) size o the thin lm transistor ( F ). T e smaller the F DEL size, the better the spatial resolution. DEL size o 100 microns provides a spatial resolution o about 5 lp mm (available only in some digital mammography systems). DEL size o 200 microns provides a spatial resolution o about 2.5 lp mm (general radiography)—lower than that achieved with 400 speed intensi ying screen system. A 100 speed intensi ying screen system o ers a spatial resolution o about 10 lp mm—signi cantly greater than, and currently unachievable in, digital imaging. Spatial resolution in digital imaging is xed, but it is very important that radiographers are alert to the opportunity they have to utilize and control the remaining recorded detail actors (motion and geometric actors). 185. (C) When tissue densities within a part are very dissimilar (e.g., chest x-ray), the analog screen– lm radiographic result can be unacceptably high contrast. o “even out” these densities and produce a more appropriate scale o grays, exposure actors using high kilovoltage should be employed. Focalspot size is unrelated to image contrast. T e higher the grid ratio, the higher is the contrast. Exposure actors using high milliampere-seconds generally result in unnecessary patient exposure. In digital imaging, predetermined algorithm selections control the required contrast requirements. 186. (D) A QA program includes regular overseeing o all components o the imaging system—equipment calibration, lm and cassettes, processor, x-ray equipment, and so on. With regular maintenance, testing, and repairs, equipment should operate e ciently and consistently. In turn, radiographic quality will be consistent, and repeat exposures will be minimized, thereby reducing patient exposure. 187. (B) Every x-ray image can be evaluated according to its spatial resolution and its contrast resolution.

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T ese qualities are closely related to the clarity, or detail, o the radiographic image. Spatial requency can be used as an indication measure o spatial resolution. Spatial requency is measured in line pairs per millimeter. One line pair is de ned as one black line on a light background having an interspace o the same width. Spatial resolution increases as spatial requency increases, i.e., they are directly related. 188. (A) DXA imaging is used to evaluate BMD. It is the most widely used method o bone densitometry—it is low-dose, precise, and uncomplicated to use perorm. DXA uses two photon energies—one or sof tissue and one or bone. Since bone is denser and attenuates x-ray photons more readily, their attenuation is calculated to represent the degree o bone density. Sof tissue attenuation in ormation is not used to measure bone density. Any images obtained in DXA bone densitometry are strictly to evaluate the accuracy o the region o interest (ROI); they are not used or urther diagnostic purposes— additional diagnostic examinations are done or any required urther evaluation. Bone densitometry DXA can be used to evaluate bone mineral content o the body or part o it, to diagnose osteoporosis, or to evaluate the e ectiveness o treatments or osteoporosis. 189. (A) I a structure o a given length is not positioned parallel to the recording medium (PSP or lm), it will be projected smaller than its actual size ( oreshortened). An example o this can be a lateral projection o the third digit. I the nger is positioned so as to be parallel to the IR, no distortion will occur. I , however, the nger is positioned so that its distal portion rests on the cassette while its proximal portion remains a distance rom the IR, oreshortening will occur. 190. (B) Digital imaging exposure data recognition (EDR) and automatic rescaling o er wide latitude and automatic optimization o the values o interest (VOI) in the radiologic image. EDR, using the selected processing algorithm and its LU , enables compensation or approximately 80% underexposure and 500% overexposure. While automatic computerized optimization o the radiologic image is a wonder ul tool, radiographers must be even more aware o their responsibility to keep patient dose to a minimum. Overexposure, though correctable via EDR, results in increased patient dose;

underexposure results in decreased image quality because o increased image noise. 191. (B) T e milliampere-seconds (mAs) ormula is milliamperage × time = mAs. With two o the actors known, the third can be determined. o nd the milliampere-seconds value that was used originally, substitute the known values: 300 × 0.1 = 30 We have increased the kilovoltage to 86 kV, an increase o 15%, which has an e ect similar to that o doubling the milliampere-seconds. T ere ore, only 15 mAs is now required as a result o the kilovoltage increase: mA × s = mAs 400x = 15 T us, x = 0.0375-s exposure = 37.5 ms. 192. (D) Static electricity can be a problem in screen lm imaging, especially in cool, dry weather. Sliding the lm in and out o the cassette IR can be the cause o a static electrical buildup and subsequent discharge. Removing one’s sweater in the darkroom on a dry winter day can cause static electrical sparking. T e lm exposed by a large static discharge (tree static) requently exhibits black, branching arti acts such as those illustrated. Poor screen– lm contact results in very blurry areas o the nished radiograph. A oreign body in the IR will be sharply imaged on the nished radiograph. An inverted ocused grid will result in an area o exposure down the middle o the image and grid cuto everywhere else. 193. (D) A C imaging system has three component parts—a gantry, a computer, and an operating console. T e gantry component includes an x-ray tube, a detector array, a high voltage generator, a collimator assembly, and a patient couch with its motorized mechanism. While the C x-ray tube is similar to direct-projection x-ray tubes, it has several special requirements. T e C x-ray tube must have a very high short-exposure rating and must be capable o tolerating several million heat units while still having a small ocal spot or optimal resolution. o help tolerate the very high production o heat units, the anode must be capable o high-speed rotation. T e x-ray tube produces a pulsed x-ray beam (1–5 ms) using up to about 1,000 mA.

Answers: 188–200

194. (C) T e gure illustrates that as distance rom a light x-ray source increases, the light x-rays diverge and cover a larger area; the quantity o light x-ray available per unit area becomes less and less as distance increases. T e intensity (quantity) o light x-ray decreases according to the inverse square law; that is, the intensity at a particular distance rom its source is inversely proportional to the square o the distance. As the distance between the x-ray tube and image receptor increases, exposure rate (and IR exposure) decreases according to the inverse square law. Because the anode’s ocal track is beveled, x-ray photons can reely diverge toward the cathode end o the x-ray tube. However, the “heel” o the ocal track prevents x-ray photons rom diverging toward the anode end o the tube. his results in varying intensity with ewer photons at the anode end and more photons at the cathode end. X-ray tube targets are constructed according to the line- ocus principle—the ocal spot is angled to the vertical. As the actual ocal spot is projected downward, it is oreshortened; thus, the e ective ocal spot is always smaller than the actual ocal spot. 195. (B) Because the ocal spot (track) o an x-ray tube is along the anode’s beveled edge, photons produced at the target are able to diverge considerably toward the cathode end o the x-ray tube but are absorbed by the heel o the anode at the opposite end o the tube. T is results in a greater number o x-ray photons distributed toward the cathode end, which is known as the anode heel e ect. T e e ect o this restricting heel is most pronounced when the x-ray photons are required to diverge more, as would be the case with short SID, large-size IRs and steeper (smaller) target angles. 196. (B) I the exposure time is cut in hal , one normally would double the milliamperage to maintain the same milliampere-seconds value and, consequently, the same receptor exposure and radiographic density in SF imaging. However, increasing the kilovoltage by 15% has a similar e ect. For example, i the original kilovoltage were 85 kV, 15% o this is 13, and there ore, the new kilovoltage would be 98 kV. T e same percentage value would be used to cut the radiographic density (in SF imaging) in hal (reduce kilovoltage by 15%).

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197. (D) In the RAO position, the sternum must be visualized through the thorax and heart. Prominent pulmonary vascular markings can hinder good visualization. A method requently used to overcome this problem is to use a milliampere-seconds value with a long exposure time. T e patient is permitted to breathe normally during the (extended) exposure and by so doing blurs out the prominent vascularities. 198. (C) High-speed imaging systems are valuable or reducing patient exposure and patient motion. However, some detail will be sacri ced, and quantum mottle can cause urther image impairment. In general, doubling the screen– lm speed doubles the radiographic density, thereby requiring that the milliampere-seconds value be halved to maintain the original radiographic density. Changing rom 200 to 400 screens requires halving the milliampere-seconds value to 9 mAs. T e new exposure time, using 400 mA, is 400x = 9. T us, x = 0.0225-s exposure using 400 mA and 400-speed screens (0.0225 = 22.5 ms). 199. (B) T e automatic lm processor has a number o component systems. T e transport system moves lm rom solution to solution between rollers, changing the direction o the lm around critical turns. T e circulation system unctions to agitate, mix, and lter solutions. T e temperature control system unctions to monitor and control solution temperature. T e replenishment system serves to monitor the solution and replace it as needed. Guide shoes are ound at crossover and turnaround assemblies and unction to direct the lm around corners as it changes direction. I a guide shoe becomes misaligned, it will scratch the emulsion and leave the characteristic guide-shoe marks running in the direction o lm travel, as seen in the radiograph shown. Pi lines appear as plus-density lines running perpendicular to the direction o lm travel; they are sometimes seen in new processors or af er a complete maintenance overhaul. Hesitation marks are plus-density lines occurring as a result o pauses, or hesitations, in a aulty roller transport system. 200. (B) Manu acturers o x-ray equipment must ollow guidelines that state maximum x-ray output at speci c distances, total quantities o ltration, positive beam limitation, and other guidelines.

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Radiographers must practice sa e principles o operation; preventive maintenance and quality control (QC) checks must be per ormed at speci c intervals to ensure continued sa e equipment perormance. Radiologic QC involves monitoring and regulating the variables associated with image production and patient care. HVL testing provides beam quality in ormation that is di erent rom that obtained rom kV testing. HVL is de ned as the thickness o any absorber that will reduce x-ray beam intensity to one-hal its original value. It is determined by measuring the beam intensity without an absorber and then recording the intensity as successive millimeters o aluminum are added to the radiation eld. It is inf uenced by the type o recti cation, total ltration, and kV. An x-ray tube HVL should remain almost constant. I HVL decreases, it is an indication o a decrease in the actual kV. I the HVL increases, it indicates the deposition o vaporized tungsten on the inner sur ace o the glass envelope (as a result o tube aging) or an increase in the actual kV. 201. (B) Attenuation (decreased intensity through scattering or absorption) o the x-ray beam is a result o its original energy and its interactions with di erent types and thicknesses o tissue. T e greater the original energy quality (the higher the kilovoltage) o the incident beam, the less is the attenuation. T e greater the e ective atomic number o the tissues (tissue type and pathology determine absorbing properties), the greater is the beam attenuation. T e greater the volume o tissue (subject density and thickness), the greater is the beam attenuation. 202. (B) Manu acturers o x-ray equipment must ollow guidelines that state maximum x-ray output at speci c distances, total quantities o ltration, positive beam limitation, and other guidelines. Radiographers must practice sa e principles o operation; preventive maintenance and quality control (QC) checks must be per ormed at speci c intervals to ensure continued sa e equipment perormance. Radiologic QC involves monitoring and regulating the variables associated with image production and patient care. HVL testing provides beam quality in ormation that is di erent rom that obtained rom kV testing. HVL is de ned as the thickness o any absorber that

will reduce x-ray beam intensity to one-hal its original value. It is determined by measuring the beam intensity without an absorber and then recording the intensity as successive millimeters o aluminum are added to the radiation eld. It is in uenced by the type o recti cation, total ltration, and kV. An x-ray tube HVL should remain almost constant. I HVL decreases, it is an indication o a decrease in the actual kV. I the HVL increases, it indicates the deposition o vaporized tungsten on the inner sur ace o the glass envelope (as a result o tube aging) or an increase in the actual kV. 203. (B) A compensating lter is used to make up or widely di ering tissue densities. For example, it is di cult to obtain a satis actory image o the mediastinum and lungs simultaneously without the use o a compensating lter to “even out” the densities. With this device, the chest is radiographed using mediastinal actors, and a trough-shaped lter (thicker laterally) is used to absorb excess photons that would overexpose the lungs. T e middle portion o the lter lets the photons pass to the mediastinum almost unimpeded. Filters that absorb the photons contributing to skin dose are inherent and added lters. Compensating ltration is unrelated to elimination o scattered radiation or uoroscopy. 204. (B) X-ray lm emulsion is sensitive and requires proper handling and storage. It should be stored in a cool (40–60°F), dry (40–60% humidity) place. Exposure to excessive temperatures or humidity can lead to lm og and loss o contrast. Static marks are a result o low humidity. 205. (C) Motion is the greatest enemy o resolution. While everything else may be per ect, i motion is introduced, resolution is lost. Focal-spot blur is related to ocal-spot size; smaller ocal spots produce less blur and thus better spatial resolution. Pixel depth is directly related to shades o gray – called dynamic range – and is measured in bits. T e greater the number o bits, the more shades o gray. Dynamic range is not related to resolution. 206. (A) Diagnostic x-rays are produced within the x-ray tube when high-speed electrons are rapidly decelerated upon encountering the tungsten atoms o the anode target. T e source o electrons is the heated cathode lament; they are driven across to

Answers: 201–212

the anode ocal spot when thousands o volts (kV) are applied. When the high-speed electrons are suddenly stopped at the ocal spot, their kinetic energy is converted to x-ray photon energy. T is happens in two ways: Bremsstrahlung (“Brems”) or “braking” radiation: A high-speed electron, passing near or through a tungsten atom, is attracted and “braked” (i.e., slowed down) by the positively charged nucleus and de ected rom its course with a loss o energy. T is energy loss is given up in the orm o an x-ray photon. T e electron might not give up all its kinetic energy in one interaction; it can go on to have several more interactions deeper in the anode, each time producing an x-ray photon having less and less energy. T is is one reason the x-ray beam is polyenergetic, that is, has a spectrum o energies. Brems radiation comprises 70% to 90% o the x-ray beam. Characteristic radiation: In this case, a highspeed electron encounters a tungsten atom within the anode and ejects a K shell electron, leaving a vacancy in that shell. An electron rom the adjacent L shell moves to the K shell to ll its vacancy and in doing so emits a K characteristic ray. T e energy o the characteristic ray is equal to the di erence in energy between the K and L shell energy levels. Characteristic radiation comprises 10% to 30% o the x-ray beam. Photoelectric e ect and Compton scatter are interactions that occur between x-ray photons and matter. 207. (D) High kV may be desirable in terms o patient dose, tube li e, and making more details visible, but use o excessively high kV will result in production o avoidable amounts o scattered radiation and og, resulting in diminished visibility o image details. Much o the scattered radiation produced is highly energetic and exits the patient along with use ul image- orming radiation. T e scattered radiation carries no use ul in ormation but adds noise in the orm o og, thereby impairing detail visibility. Because scattered radiation can have such a devastating e ect on image contrast, it is essential that radiographers are knowledgeable about methods o reducing its production. T e three actors that have a signi cant e ect on the production o scattered radiation are beam restriction (i.e., size o irradiated eld), kV, and thickness volume and density o tissues.

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Perhaps the most important way to limit the production o scattered radiation and improve contrast is by limiting the size o the irradiated eld, that is, through beam restriction. As the size o the x-ray eld is reduced, there is less area and tissue volume or scattered radiation to be generated. As the volume and or density o the irradiated tissues increase(s), so does scattered radiation. T icker and more dense anatomic structures will generate more scattered radiation. Compression o certain parts can occasionally be used to minimize the e ect o scatter, but close collimation can always be used e ectively. 208. (B) Rare earth phosphors have a greater conversion e ciency than do other phosphors. Lanthanum oxybromide is a blue-emitting rare earth phosphor, and gadolinium oxysul de is a green-emitting rare earth phosphor. Cesium iodide is the phosphor used on the input screen o image intensi ers; it is not a rare earth phosphor. 209. (B) T e image is an AP projection o the abdomen. T e most obvious characteristic is its lack o contrast. T e image is very gray because a grid was not employed. T e major unction o a grid it is to improve image contrast. Remember that a grid is usually indicated or parts measuring greater than 10 cm. Image detail is related to image geometry, which is not impacted here. T e lack o contrast impacts detail visibility. 210. (A) When grid ratio decreases, total land content decreases and a smaller amount o scattered radiation is trapped be ore reaching the IR. More grays rom scattered radiation og are there ore recorded, and a longer scale o contrast results. Receptor exposure would increase with a decrease in grid ratio. Grid ratio is unrelated to distortion. 211. (B) X-ray lm emulsion becomes more sensitive to sa elight og ollowing exposure to uorescent light rom intensi ying screens. Care must be taken not to leave exposed lm on the darkroom workbench or any length o time because its sensitivity to sa elight og is now greatly heightened. 212. (A) Proper use o ocal-spot size is o paramount importance in magni cation radiography. A magnied image that is diagnostic can be obtained only by

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using a ractional ocal spot o 0.3 mm or smaller. T e amount o blur or geometric unsharpness produced by ocal spots that are larger in size render the radiograph undiagnostic.

IR/ lm. An object can be alsely imaged ( oreshortened or elongated) by incorrect placement o the tube, the body part, or the IR. Only one o the three need be misaligned or distortion to occur.

213. (D) As OID is increased, spatial resolution is diminished as a result o magni cation distortion. I the OID cannot be minimized, an increase in SID is required to reduce the e ect o magni cation distortion. However, the relationship between OID and SID is not an equal relationship. In act, to compensate or every 1 in o OID, an increase o 7 in o SID is required. T ere ore, an OID o 6 in requires an SID increase o 42 in. T is is why a chest radiograph with a 6-in air gap usually is per ormed at a 10-f SID.

218. (A) Emphysema is abnormal distension o the pulmonary alveoli (or tissue spaces) with air. It is characterized with attening o the hemidiaphragm and widening o the intercostal spaces. T e presence o abnormal amounts o air makes a decrease rom normal exposure actors necessary to avoid excessive receptor exposure. Congestive heart ailure, pneumonia, and pleural e usion all involve abnormal amounts o uid in the chest and, thereore, require an increase in exposure actors.

214. (D) Grid ratio is de ned as the ratio between the height o the lead strips and the width o the distance between them (i.e., their height divided by the distance between them). I the height o the lead strips is 4.0 mm and the lead strips are 0.25 mm apart, the grid ratio must be 16:1 (4.0 divided by 0.25). T e thickness o the lead strip is unrelated to grid ratio.

219. (B) Many IR have a thin lead- oil layer behind their rear section to absorb backscattered radiation that is energetic enough to exit the rear, strike the metal back, and bounce back to og the image. T e lead oil absorbs the backscatter be ore it can og the PSP.

215. (A) T e line- ocus principle is a geometric principle illustrating that the actual ocal spot is larger than the e ective (projected) ocal spot. T e actual ocal spot (target) is larger, to accommodate heat over a larger area, and is angled so as to project a smaller ocal spot, thus maintaining spatial resolution by reducing blur. T e relationship between the exposure given the IR and the resulting receptor exposure is expressed in the reciprocity law; the relationship between the SID and resulting IR exposure is expressed by the inverse square law. Grid ratio and lines per inch are unrelated to the line- ocus principle. 216. (C) Receptor exposure is greatly a ected by changes in the SID, as expressed by the inverse square law o radiation. As distance rom the radiation source increases, exposure rate decreases, and IR exposure decreases. Exposure rate is inversely proportional to the square o the SID. Aluminum ltration, kilovoltage, and scattered radiation all have a signi cant e ect on receptor exposure, but they are not the controlling actors. 217. (D) Shape distortion is caused by misalignment o the x-ray tube, the part to be radiographed, and the

220. (B) Fluorescence occurs when an intensi ying screen absorbs x-ray photon energy, emits light, and then ceases to emit light as soon as the energizing source ceases. Phosphorescence occurs when an intensi ying screen absorbs x-ray photon energy, emits light, and continues to emit light or a short time af er the energizing source ceases. Quantum mottle is the reckle-like appearance on some radiographs made using a very ast imaging system. T e brightness o a uoroscopic image is ampli ed through image intensi cation. 221. (D) Review the groups o actors. First, because the milliampere-seconds value has no e ect on the scale o contrast produced, eliminate milliampereseconds rom consideration by drawing a line through the column. T en, check the two entries in each column that are likely to produce shorter-scale contrast. For example, in the kilovoltage column, because lower kilovoltage will produce shorter-scale contrast, place checkmarks next to the 70 and 80 kV. In the screen– lm column, the aster screens (400) will produce higher (shorter-scale) contrast than the slower screens; place a checkmark next to each. Because higher-ratio grids permit less scattered radiation to reach the IR, the 10:1 and 12:1 grids will produce a shorter scale o contrast than the lower-ratio grids; check them. As the volume o

Answers: 213–228

irradiated tissue decreases, so does the amount o scattered radiation produced, and consequently, the shorter is the scale o radiographic contrast; thereore, check the 11 × 14 and 8 × 10 in eld sizes. An overview shows that the actors in groups (A) and (C) have two checkmarks, whereas the actors in group (D) have our checkmarks, indicating that group (D) will produce the shortest-scale contrast. 222. (C) Quality Control re ers to our equipment and its sa e and accurate operation. Various components must be tested at speci ed intervals, and test results must be within speci ed parameters. Any deviation rom those parameters must be corrected. Examples o equipment components that are tested annually are the ocal-spot size, linearity, reproducibility, ltration, kV, and exposure time. Congruence is a term used to describe the relationship between the collimator light eld and the actual x-ray eld—they must be congruent (i.e., match) to within 2% o the SID. Radiographic equipment collimators should be inspected and veri ed as accurate semiannually, that is, twice a year. Kilovoltage settings can most e ectively be tested using an electronic kV meter; to meet required standards, the kV should be accurate to within + –4 kV. Reproducibility testing should speci y that radiation output be consistent to within + –5%. 223. (C) T e exposed CR cassette is placed into the CR scanner reader, where the PSP (SPS) is removed automatically. T e latent image appears as the PSP is scanned by a narrow, high-intensity helium–neon laser to obtain the pixel data. As the plate is scanned in the CR reader, it releases a violet light—a process re erred to as photostimulated luminescence (PSL). T e luminescent light is converted to electrical energy representing the analog image. T e electrical energy is sent to an analog-to-digital converter (ADC), where it is digitized and becomes the digital image that is displayed eventually (af er a short delay) on a high-resolution monitor and or printed out by a laser printer. T e digitized images can also be manipulated in postprocessing, transmitted electronically, and stored archived. 224. (B) As the lm emulsion is exposed to light or x-rays, latent image ormation takes place. T e exposed silver halide crystals are reduced to black metallic silver by the developer reducing agents in

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the automatic processor’s developer solution. T e preservative helps to prevent oxidation o the developer solution. T e activator provides the necessary alkalinity or the developer solution, and hardener is added to the developer in automatic processing to keep emulsion swelling to a minimum. 225. (A) Grids are composed o alternate strips o lead and interspace material and are used to trap scattered radiation af er it emerges rom the patient and be ore it reaches the IR. Accurate centering o the x-ray tube is required. I the x-ray tube is o center but within the recommended ocusing distance, there usually will be an overall loss o receptor exposure. Over- or underexposure under the anode is usually the result o exceeding the ocusing distance limits in addition to being o -center. 226. (D) T e chest is composed o tissues with widely di ering densities (bone and air). In an e ort to “even out” these tissue densities and better visualize pulmonary vascular markings, high kilovoltage generally is used. T is produces more uni orm penetration and results in a longer scale o contrast with visualization o the pulmonary vascular markings as well as bone (which is better penetrated) and air densities. T e increased kilovoltage also a ords the advantage o greater exposure latitude (an error o a ew kilovolts will make little, i any, di erence). T e act that the kilovoltage is increased means that the milliampere-seconds value is reduced accordingly, and thus patient dose is reduced as well. A grid usually is used whenever high kilovoltage is required. 227. (B) First, evaluate the change(s): T e kilovoltage was increased by 15% (78 + 15% = 90). A 15% increase in kilovoltage will double the image receptor exposure; there ore, it is necessary to use hal the original milliampere-seconds value to maintain the original IR exposure. T e original milliampereseconds value was 28 mAs (300 mA × 0.07 second [70 ms] 28 mAs), so we now need 14 mAs, using 500 mA. Because mA × s mAs: 500x = 14 x = 0.028 s (28 ms) 228. (D) Pathologic processes and abnormal conditions that alter tissue composition or thickness can

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have a signi cant e ect on receptor exposure. T e radiographer must be aware o these variants and processes to make an appropriate and accurate adjustment o technical actors. Examples o additive pathologic conditions: • • • • • • •

Ascites Rheumatoid arthritis Paget disease Pneumonia Atelectasis Congestive heart ailure Edematous tissue

Examples o destructive pathologic conditions: • • • • • •

Osteoporosis Osteomalacia Pneumoperitoneum Emphysema Degenerative arthritis Atrophic and necrotic conditions

229. (C) Be ore the radiologic examination begins, patients of en need to change their clothing and or remove radiopaque objects (e.g., jewelry, dentures, and braided hair) rom superimposition on structures o interest. T e gure illustrates multiple braids o hair superimposed on skull structures, as well as nose and ear jewelry. While loose hair is radiolucent, hair that is braided becomes more dense and is of en imaged radiographically. T e ensuing arti acts can inter ere with accurate diagnosis otherwise, the bony detail is good and no motion is present. 230. (A) Geometric unsharpness is a ected by all three actors listed. As OID increases, so does magni cation—there ore, OID is directly related to magni cation. As SOD and SID decrease, magni cation increases—there ore, SOD and SID are inversely related to magni cation. 231. (D) T e input phosphor o image intensi ers is usually made o cesium iodide. For each x-ray photon absorbed by cesium iodide, approximately 5,000 light photons are emitted. As the light photons strike a photoemissive photocathode, a number o electrons are released rom the photocathode and ocused toward the output side o the image tube by voltage applied to the negatively

charged electrostatic ocusing lenses. T e electrons are then accelerated through the neck o the tube where they strike the small (0.5–1 in) output phosphor that is mounted on a at glass support. T e entire assembly is enclosed within a 2- to 4-mm thick vacuum glass envelope. Remember that the image on the output phosphor is mini ed, brighter, and inverted (electron ocusing causes image inversion). Input screen diameters o 5 to 12 in are available. Although smaller diameter input screens improve resolution, they do not permit a large FOV, that is, viewing o large patient areas. Dual- and triple- eld image intensi ers are available that permit magni ed viewing o uoroscopic images. o achieve magni cation, the voltage to the ocusing lenses is increased and a smaller portion o the input phosphor is used, thereby resulting in a smaller FOV. Because mini cation gain is now decreased, the image is not as bright. T e mA is automatically increased to compensate or the loss in brightness when the image intensier is switched to magni cation mode. Entrance skin exposure (ESE) can increase dramatically as the FOV decreases (i.e., as magni cation increases). As FOV decreases, magni cation o the output screen image increases, there is less noise because increased mA provides a greater number o x-ray photons, and contrast and spatial resolution improve. T e ocal point in the magni cation mode is urther away rom the output phosphor (as a result o increased voltage applied to the ocusing lenses) and there ore the output image is magni ed. 232. (D) Collimators restrict the size o the irradiated eld, thereby limiting the volume o irradiated tissue, and hence less scattered radiation is produced. Once radiation has scattered and emerged rom the body, it can be trapped by the grid’s lead strips. Grids e ectively remove much o the scattered radiation in the remnant beam be ore it reaches the IR. Compression can be applied to reduce the e ect o excessive atty tissue (e.g., in the abdomen); in e ect, reducing the thickness o the part to be radiographed. 233. (A) Kilovoltage is the qualitative regulating actor; it has a direct e ect on photon energy. T at is, as kilovoltage is increased, photon energy increases. Photon energy is inversely related to wavelength. T at is, as photon energy increases, wavelength decreases. Photon energy is unrelated to milliamperage.

Answers: 229–241

234. (C) Every box o lm comes with the expiration date noted. Film used af er its expiration date usually will su er a loss o speed and contrast and will exhibit og. Film should be ordered in quantities that will ensure that it is used be ore it becomes outdated, and it should be rotated in storage so that the oldest is used rst. 235. (A) T e screen– lm system and radiographic density are directly proportional; that is, i the system speed is doubled, the radiographic density is doubled. In this case, we started at 40 mAs with a 200-speed system. I the system speed is doubled to 400, we should decrease the milliampere-seconds to 20 mAs. I the speed is again doubled to 800, we use hal the 20 mAs, or 10 mAs. Or milliampere-seconds conversion actors and the ollowing ormula may be used: Screen speed factor 1 mAs 1 = Screen speed factor 2 mAs 2 2 40 = 0.5 x 2x = 20 T us, x = 10 mAs with a 800-speed screen– lm system. 236. (B) According to the 15% rule, i the kilovoltage is increased by 15%, receptor exposure will be doubled. T ere ore, to compensate or this change and to maintain IR exposure, the milliampere-seconds value should be reduced to 4 mAs. 237. (A) Limiting the size o the irradiated eld is a most e ective method o decreasing the production o scattered radiation. T e smaller the volume o tissue irradiated, the smaller is the amount o scattered radiation generated; this can be accomplished using compression (prone position instead o supine or a compression band). Use o a grid does not a ect the production o scattered radiation but rather removes it once it has been produced. 238. (D) Compression o the breast tissue during mammographic imaging improves the technical quality o the image or several reasons. Compression brings breast structures into closer contact with the IR, thus reducing geometric blur and improving detail. As the breast tissue is compressed and essentially becomes thinner, less scattered radiation is

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produced. Compression serves as excellent immobilization as well. 239. (D) Distortion is caused by improper alignment o the tube, body part, and IR. Anatomic structures within the body are rarely parallel to the IR in a simple recumbent position. In an attempt to overcome this distortion, we position the part to be parallel with the IR or angle the central ray to “open up” the part. Examples o this technique are obliquing the pelvis to place the ilium parallel to the IR or angling the central ray cephalad to “open up” the sigmoid colon. 240. (D) One o the biggest advantages o CR is the dynamic range, or latitude, it o ers. T e characteristic curve o x-ray lm emulsion has a certain “range o correct exposure,” limited by the toe and shoulder o the curve. In CR, there is a linear relationship between the exposure, given the PSP (SPS) and its resulting luminescence as it is scanned by the laser. T is a ords much greater exposure latitude, and technical inaccuracies can be e ectively eliminated. Overexposure o up to 500% and underexposure o up to 80% are reported as recoverable, thus eliminating most retakes. T is surely a ords increased e ciency; however, this does not mean that images can be exposed arbitrarily. T e radiographer must keep dose reduction in mind. T e same exposure actors as screen– lm systems, or less, generally are recommended or CR. Intensi ying screens used in screen– lm x-ray imaging tend to produce high contrast. T e aster the screens, the higher is the contrast; higher contrast of en is associated with decreased latitude. AEC re ers to automatic exposure control and is unrelated to dynamic range or latitude. 241. (D) T e abdomen radiograph shown in the gure demonstrates motion blur. T is can be seen particularly in the upper abdomen and in the bowel gas patterns. Motion obliterates detail. Patients who are in pain of en are unable to cooperate as ully as patients who are not in pain. Care ul positioning and patient instruction are help ul, but it remains use ul to use the shortest exposure time possible. T e radiograph also demonstrates good long-scale contrast that enables visualization o many tissue densities. T e dark horizontal line across the abdomen is a clothing arti act resulting rom a taut elastic underwear waist-band.

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4: Image Acquisition and Evaluation

242. (B) Sir God rey Newbold Houns eld created the rst C unit, describing the reconstruction o data taken rom multiple projection angles. Alan MacLeod Cormack worked with the complex mathematical algorithms required or image reconstruction. T eir rst commercial C head scanner was available in 1971. In 1979, Houns eld and Cormack shared the Nobel Prize in Medicine or their historic work with this new imaging science. o express the beam-attenuation characteristics o various tissues, the Houns eld unit (HU) is used. HUs can also be re erred to as C numbers or density values. God rey Houns eld assigned a value o 0 to distilled water, a value o + 1,000 to dense osseous tissue, and a value o –1,000 to air. T ere is a direct relationship between the HU and tissue attenuation coe cient. T e greater the attenuation coe cient o the particular tissue, the higher the HU value. One HU represents a 0.1% di erence between the particular tissue attenuation characteristics and that o distilled water. HU value accuracy can be a ected by equipment calibration, volume averaging, and image arti acts. 243. (C) Signi cant scattered radiation is generated within the part when imaging large or dense body parts and when using high kilovoltage. A radiographic grid is made o alternating lead strips and interspace material; it is placed between the patient and the IR to absorb energetic scatter emerging rom the patient. Although a grid prevents much o the scattered radiation rom reaching the radiograph, its use does necessitate a signi cant increase in patient exposure. 244. (D) o change nongrid to grid exposure or to adjust exposure when changing rom one grid ratio to another, it is necessary to recall the actor or each grid ratio: No grid = 5:1 grid = 6:1 grid = 8:1 grid = 12:1 (or 10:1) grid = 16:1 grid =

1× 2× 3× 4× 5× 6×

original mAs original mAs original mAs original mAs original mAs original mAs

T ere ore, to change rom nongrid to a 12:1 grid, multiply the original milliampere-seconds value by a actor o 5. A new milliampere-seconds value o 15 is required.

245. (C) Receptor exposure is directly proportional to milliampere-seconds. I exposure time is halved rom 40 ms (0.04 or 1/25 second) to 0.02 (1/50 second), IR exposure will be cut in hal . Changing to 150 mA also will halve the milliampere-seconds, e ectively halving the IR exposure. I the kilovoltage is decreased by 15%, rom 85 to 72 kV, receptor exposure will be halved according to the 15% rule. o cut the receptor exposure in hal , the milliampere-seconds value must be reduced to 6 mAs (rather than 10 mAs). 246. (B) CR systems convert x-ray photons into use ul in ormation much more e ciently than screenlm systems, hence a ar better DQE. CR also converts that in ormation over a ar wider exposure range (about 104 times wider) than screen lm. T e single negative aspect o CR is its limited spatial resolution (image detail). While screen– lm systems resolve about 10 to 15 lp mm, CR resolution is about 3 to 5 lp mm. 247. (C) About hal the silver in a lm emulsion remains to orm the image. T e other hal is removed rom the lm during the xing process. T ere ore, xer solution has a high silver content. Silver is a toxic metal and cannot simply be disposed o into the public sewer system. Since silver is also a precious metal, it becomes nancially wise to recycle the silver removed rom x-ray lm. T e three most commonly used silver recovery systems are the electrolytic, metallic replacement, and chemical precipitation methods. In electrolytic units, an electric current is passed through the xer solution. Silver ions are attracted to and become plated onto the negative electrode o the unit. T e plated silver is periodically scraped rom the cathode and accurately measured so that the hospital can be reimbursed appropriately. T e electrolytic method is a practical recovery system or moderate- and high-use processors. T e metallic replacement (or displacement) method o silver recovery uses a steel mesh steel wool type o cartridge that traps silver as xer is run through it. T is system is use ul or low-volume processors and is of en also used as a backup to the electrolytic unit. Chemical precipitation adds chemicals that release electrons into the xer solution. T is causes the metallic silver to precipitate out, all to the bottom o the tank, and orm a recoverable sludge. T is method is used principally by commercial silver dealers.

Answers: 242–250

248. (A) A 15-minute oblique image o an IVU is pictured. IVU requires the use o iodinated contrast medium. Low kilovoltage (about 70 kV) usually is employed to enhance the photoelectric e ect and, in turn, better visualize the renal collecting system. High kilovoltage will produce excessive scattered radiation and obviate the e ect o the contrast agent. A higher milliamperage with a shorter exposure time is pre erred to decrease the possibility o motion. 249. (C) T e iodine-based contrast material used in IVU gives optimal opaci cation at 60 to 70 kV. Use o higher kilovoltage will negate the e ect o the contrast medium; a lower contrast will be

253

produced, and poor visualization o the renal collecting system will result. GI and BE examinations employ high kilovoltage exposure actors (about 120 kV) to penetrate through the barium. In chest radiography, high kilovoltage technical actors are pre erred or maximum visualization o pulmonary vascular markings made visible with long-scale contrast. 250. (B) T e arti act shown in the gure has sharply delineated edges, indicating that it is located adjacent to the PSP within the IP. T e arther the object is rom the IR, the more blurred its edges will be as a result o magni cation distortion.

Subspecialty List

QUESTION NUMBER AND SUBSPECIALTY correspond to subcategories in each o the f ve ARRT examination specif cation sections 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30.

254

Criteria or image evaluation Image acquisition and evaluation Image acquisition and evaluation Image processing and quality assurance Criteria or image evaluation Selection o technical actors Selection o technical actors Selection o technical actors Image processing and quality assurance Selection o technical actors Image processing and quality assurance Criteria or image evaluation Selection o technical actors Selection o technical actors Image processing and quality assurance Selection o technical actors Selection o technical actors Selection o technical actors Image processing and quality assurance Criteria or image evaluation Image processing and quality assurance Image processing and quality assurance Criteria or image evaluation Criteria or image evaluation Selection o technical actors Image processing and quality assurance Image processing and quality assurance Image processing and quality assurance Selection o technical actors Criteria or image evaluation

31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65.

Image processing and quality assurance Selection o technical actors Selection o technical actors Criteria or image evaluation Image processing and quality assurance Image processing and quality assurance Image processing and quality assurance Selection o technical actors Selection o technical actors Criteria or image evaluation Selection o technical actors Criteria or image evaluation Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Image processing and quality assurance Image processing and quality assurance Criteria or image evaluation Criteria or image evaluation Selection o technical actors Selection o technical actors Image processing and quality assurance Selection o technical actors Image processing and quality assurance Image processing and quality assurance Selection o technical actors Selection o technical actors Image processing and quality assurance Image processing and quality assurance Image processing and quality assurance Image processing and quality assurance Selection o technical actors Criteria or image evaluation Selection o technical actors

Subspecialty List

66. 67. 68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 78. 79. 80. 81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92. 93. 94. 95. 96. 97. 98. 99. 100. 101. 102. 103. 104. 105. 106. 107. 108. 109. 110. 111. 112. 113. 114. 115.

Image processing and quality assurance Selection o technical actors Image processing and quality assurance Image processing and quality assurance Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Image processing and quality assurance Selection o technical actors Criteria or image evaluation Selection o technical actors Selection o technical actors Image processing and quality assurance Selection o technical actors Selection o technical actors Image processing and quality assurance Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Image processing and quality assurance Criteria or image evaluation Criteria or image evaluation Selection o technical actors Image processing and quality assurance Image processing and quality assurance Selection o technical actors Selection o technical actors Criteria or image evaluation Selection o technical actors Selection o technical actors Image processing and quality assurance Criteria or image evaluation Selection o technical actors Selection o technical actors Criteria or image evaluation Selection o technical actors Image processing and quality assurance Image processing and quality assurance Selection o technical actors Criteria or image evaluation Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors

116. 117. 118. 119. 120. 121. 122. 123. 124. 125. 126. 127. 128. 129. 130. 131. 132. 133. 134. 135. 136. 137. 138. 139. 140. 141. 142. 143. 144. 145. 146. 147. 148. 149. 150. 151. 152. 153. 154. 155. 156. 157. 158. 159. 160. 161. 162. 163. 164. 165.

Criteria or image evaluation Image processing and quality assurance Image processing and quality assurance Criteria or image evaluation Image processing and quality assurance Image processing and quality assurance Image processing and quality assurance Image processing and quality assurance Selection o technical actors Image processing and quality assurance Image processing and quality assurance Image processing and quality assurance Selection o technical actors Image processing and quality assurance Selection o technical actors Image processing and quality assurance Selection o technical actors Image processing and quality assurance Image processing and quality assurance Criteria or image evaluation Selection o technical actors Criteria or image evaluation Criteria or image evaluation Selection o technical actors Selection o technical actors Selection o technical actors Image processing and quality assurance Selection o technical actors Selection o technical actors Image processing and quality assurance Selection o technical actors Criteria or image evaluation Image processing and quality assurance Criteria or image evaluation Selection o technical actors Image processing and quality assurance Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Image processing and quality assurance Criteria or image evaluation Selection o technical actors Selection o technical actors Selection o technical actors Image processing and quality assurance Selection o technical actors Selection o technical actors Image processing and quality assurance

255

256

166. 167. 168. 169. 170. 171. 172. 173. 174. 175. 176. 177. 178. 179. 180. 181. 182. 183. 184. 185. 186. 187. 188. 189. 190. 191. 192. 193. 194. 195. 196. 197. 198. 199. 200. 201. 202. 203. 204. 205. 206. 207. 208.

4: Image Acquisition and Evaluation

Image processing and quality assurance Selection o technical actors Criteria or image evaluation Selection o technical actors Selection o technical actors Selection o technical actors Image processing and quality assurance Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Criteria or image evaluation Selection o technical actors Selection o technical actors Selection o technical actors Image processing and quality assurance Selection o technical actors Image processing and quality assurance Selection o technical actors Image processing and quality assurance Image processing and quality assurance Image processing and quality assurance Criteria or image evaluation Image processing and quality assurance Selection o technical actors Criteria or image evaluation Image processing and quality assurance Image processing and quality assurance Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Criteria or image evaluation Image processing and quality assurance Selection o technical actors Image processing and quality assurance Image processing and quality assurance Image processing and quality assurance Criteria or image evaluation Selection o technical actors Selection o technical actors Selection o technical actors

209. 210. 211. 212. 213. 214. 215. 216. 217. 218. 219. 220. 221. 222. 223. 224. 225. 226. 227. 228. 229. 230. 231. 232. 233. 234. 235. 236. 237. 238. 239. 240. 241. 242. 243. 244. 245. 246. 247. 248. 249. 250.

Criteria or image evaluation Selection o technical actors Image processing and quality assurance Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Criteria or image evaluation Image processing and quality assurance Criteria or image evaluation Selection o technical actors Image processing and quality assurance Image processing and quality assurance Image processing and quality assurance Criteria or image evaluation Selection o technical actors Selection o technical actors Selection o technical actors Criteria or image evaluation Selection o technical actors Image processing and quality assurance Selection o technical actors Selection o technical actors Image processing and quality assurance Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Image processing and quality assurance Criteria or image evaluation Selection o technical actors Selection o technical actors Selection o technical actors Selection o technical actors Image processing and quality assurance Image processing and quality assurance Selection o technical actors Selection o technical actors Criteria or image evaluation

Subspecialty List

Targeted Reading Fosbinder R, Orth D. Essentials o Radiologic Science. Baltimore, MD: Lippincott Williams & Wilkins; 2012. Bontrager KL, Lampignano JP. extbook o Radiographic Positioning and Related Anatomy. 8th ed. St Louis, MO: Mosby; 2014. Carlton RR, Adler AM. Principles o Radiographic Imaging. 5th ed. Albany, NY: Delmar; 2013. Seeram E. Digital Radiography: An Introduction. Delmar: CENGAGE Learning; 2011.

257

Bushong SC. Radiologic Science or echnologists. 10th ed. St. Louis, MO: Mosby; 2013. Fuji Photo Film Co., Ltd (FCR). Fuji Computed Radiography. Minato-Ku, Japan; 2002. Fosbinder RA, Kelsey CA. Essentials o Radiologic Science. 1st ed. New York, NY: McGraw-Hill; 2002. Saia DA. Radiography PREP. 8th ed. New York, NY: McGraw-Hill; 2015. Selman J. T e Fundamentals o Imaging Physics and Radiobiology. 9th ed. Spring eld, IL: Charles C T omas; 2000. Shephard C . Radiographic Image Production and Manipulation. 1st ed. New York, NY: McGraw-Hill; 2003.

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CHAPTER 5

Equipment Operation and Quality Control Questions

DIRECTIONS (Questions 1 through 120): Each of the numbered items or incomplete statements in this section is followed by answers or by completions of the statement. Select the one lettered answer or completion that is best in each case. 1. With what requency must radiographic equipment be checked or linearity and reproducibility? (A) (B) (C) (D)

Annually Biannually Semiannually Quarterly

2. Which o the ollowing occurs during Bremsstrahlung (Brems) radiation production? (A) An electron makes a transition rom an outer to an inner electron shell. (B) An electron approaching a positive nuclear charge changes direction and loses energy. (C) A high-energy photon ejects an outer-shell electron. (D) A low-energy photon ejects an inner-shell electron. 3.

ypical examples o digital imaging include 1. MRI 2. C 3. CR (A) (B) (C) (D)

4. Component parts o a C gantry include 1. high-voltage generator 2. multidetector array 3. x-ray tube (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

5. Design characteristics o x-ray tube targets that determine heat capacity include 1. the rotation o the anode 2. the diameter o the anode 3. the size o the ocal spot (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

6. I exposure actors o 85 kV, 400 mA, and 12 ms yield an output exposure o 150 mR, what is the milliroentgens per milliampere-seconds (mR/mAs)? (A) (B) (C) (D)

0.32 3.1 17.6 31

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

259

260

5: Equipment Operation and Quality Control

7. I a high-voltage trans ormer has 100 primary turns and 50,000 secondary turns and is supplied by 220 V and 100 A, what are the secondary voltage and current? (A) (B) (C) (D)

200 A and 110 V 200 mA and 110 kV 20 A and 100 V 20 mA and 100 kV

8. Which o the wave orms below is illustrative o high- requency current? (A) (B) (C) (D)

Diagram D Diagram E Diagram F Diagram G

9. When using the smaller eld in a dual- eld image intensi er 1. the image is magni ed 2. the image is brighter 3. a larger anatomic area is viewed (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 1, 2, and 3

10. Light-sensitive AEC devices are known as (A) (B) (C) (D)

phototimers ionization chambers sensors backup timers

11. T e electron cloud within the x-ray tube is the product o a process called

A

(A) (B) (C) (D)

B

electrolysis thermionic emission recti cation induction

12. Which o the ollowing will improve the spatial resolution o image-intensi ed images?

C

1. A very thin coating o cesium iodide on the input phosphor 2. A smaller-diameter input screen 3. Increased total brightness gain

D

(A) (B) (C) (D)

E

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

13. Which o the ollowing is (are) characteristics o the x-ray tube?

F

1. T e target material should have a high atomic number and a high melting point. 2. T e use ul beam emerges rom the port window. 3. T e cathode assembly receives both low and high voltages.

G

Figure 5-1.

(A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

Questions: 7–22

14. A parallel-plate ionization chamber receives a particular charge as x-ray photons travel through it. T is is the operating principle o which o the ollowing devices? (A) (B) (C) (D)

AEC Image intensi er Video recorder Photospot camera

15. Which o the ollowing will serve to increase the e ective energy o the x-ray beam?

18. Which o the ollowing systems unctions to compensate or changing patient/part thicknesses during uoroscopic procedures? (A) (B) (C) (D)

Automatic brightness control Mini cation gain Automatic resolution control Flux gain

19. Delivery o large exposures to a cold anode or the use o exposures exceeding tube limitation can result in

1. Increase in added ltration 2. Increase in kilovoltage 3. Increase in milliamperage

1. increased tube output 2. cracking o the anode 3. rotor-bearing damage

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

16. Which o the ollowing combinations would pose the least hazard to a particular single phase anode? (A) (B) (C) (D)

1.2-mm 0.6-mm 1.2-mm 0.6-mm

ocal spot, 92 kV, 1.5 mAs ocal spot, 80 kV, 3 mAs ocal spot, 70 kV, 6 mAs ocal spot, 60 kV, 12 mAs

17. O what material is Number 1 in Figure 5-2 made? (A) Nickel (B) Molybdenum (C) ungsten (D) Copper

20. I the primary coil o a high-voltage trans ormer is supplied by 220 V and has 400 turns and the secondary coil has 100,000 turns, what is the voltage induced in the secondary coil? (A) (B) (C) (D)

(A) (B) (C) (D)

3

5

2 7

80 kV 55 kV 80 V 55 V

As kV increases, the HVL increases. As kV decreases, the HVL decreases. I the kV is doubled, the HVL doubles. I the kV is doubled, the HVL is squared.

22. As window level increases (A) (B) (C) (D)

6

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

21. What is the relationship between kV and HVL?

4

8

1

Figure 5-2.

261

contrast scale increases contrast scale decreases brightness increases brightness decreases

262

5: Equipment Operation and Quality Control

23. Circuit devices that permit electrons to only one direction are (A) (B) (C) (D)

ow in

solid-state diodes resistors trans ormers autotrans ormers

24. Patient dose during uoroscopy is a ected by the 1. distance between the patient and the input phosphor 2. amount o magni cation 3. tissue density (A) (B) (C) (D)

1 only 3 only 2 and 3 only 1, 2, and 3

25. T e AEC backup timer unctions to 1. protect the patient rom overexposure 2. protect the x-ray tube rom excessive heat 3. increase or decrease programmed receptor exposure (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

26. Which o the ollowing devices converts mechanical energy to electrical energy? (A) (B) (C) (D)

Motor Generator Stator Rotor

27. T e essential unction o a phototimer is to (A) provide a brighter uoroscopic image (B) automatically restrict the eld size (C) terminate the x-ray exposure once the IR is correctly exposed (D) automatically increase or decrease incoming line voltages

28. A slit camera is used to measure 1. ocal-spot size 2. spatial resolution 3. intensi ying screen resolution (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

29. In which o the ollowing examinations would an IP ront with very low absorption properties be especially important? (A) (B) (C) (D)

Abdominal radiography Extremity radiography Angiography Mammography

30. Which o the ollowing causes pitting, or many small sur ace melts, o the anode’s ocal track? (A) (B) (C) (D)

Vaporized tungsten on the glass envelope Loss o anode rotation A large amount o heat to a cold anode Repeated, requent overloading

31. T e advantages o collimators over aperture diaphragms and are cones include 1. the variety o eld sizes available 2. more e cient beam restriction 3. better cleanup o scattered radiation (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 2 and 3 only

32. T e type o x-ray tube designed to turn on and o rapidly, providing multiple short, precise exposures, is (A) (B) (C) (D)

high speed grid-controlled diode electrode

Questions: 23–40

33. Characteristics o the metallic element tungsten include 1. ready dissipation o heat 2. high melting point 3. high atomic number (A) (B) (C) (D)

charge-coupled device (CCD) spot image device image intensi er television monitor

37. A high-speed electron is decelerated as is attracted to a tungsten atom nucleus. T is results in

34. Which o the illustrations in Figure 5-3 depicts the phototimer-type automatic exposure control (AEC)? (A) (B) (C) (D)

36. T e device that receives the remnant beam, converts it into light, and then increases the brightness o that light is the (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

263

Image A Image B Both illustrate a phototimer-type AEC Neither illustrates a phototimer-type AEC

(A) (B) (C) (D)

38. All the ollowing are components o the image intensi er except (A) (B) (C) (D)

Expos ure switch

Ba ckup time r

Bremsstrahlung radiation characteristic radiation Compton scatter a photoelectric e ect

the photocathode the ocusing lenses the V monitor the accelerating anode

39. Components o digital imaging include 1. computer manipulation o the image 2. ormation o an electronic image on the radiation detector 3. ormation o an x-ray image directly on the IR

A

(A) (B) (C) (D)

IR

40. Which o the ollowing is used in digital uoroscopy, replacing the image intensi er’s television camera tube?

IR

B Figure 5-3.

35. T e voltage ripple associated with a three-phase, 12-pulse recti ed generator is about (A) (B) (C) (D)

4% 13% 32% 100%

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

(A) (B) (C) (D)

Solid-state diode Charge-coupled device Photostimulable phosphor Vidicon

264

5: Equipment Operation and Quality Control

41. Which o the ollowing devices is used to control voltage by varying resistance? (A) (B) (C) (D)

Autotrans ormer High-voltage trans ormer Rheostat Fuse

42. T e regular measurement and evaluation o radiographic equipment components and their per ormance is most accurately termed as (A) (B) (C) (D)

postprocessing quality assurance quality control quality congruence

43. T e procedure whose basic operation involves reciprocal motion o the x-ray tube and IR is (A) (B) (C) (D)

cine uorography spot image device tomography image intensi cation

44. In uoroscopy, the automatic brightness control is used to adjust the (A) (B) (C) (D)

kilovoltage (kV) and milliamperage (mA) backup timer milliamperage (mA) and time kilovoltage (kV) and time

45. When the radiographer selects kilovoltage on the control panel, which device is adjusted? (A) (B) (C) (D)

Step-up trans ormer Autotrans ormer Filament circuit Recti er circuit

46. Star and wye con gurations are related to (A) (B) (C) (D)

autotrans ormers three-phase trans ormers recti cation systems AECs

47. What is the device that directs the light emitted rom the image intensi er to various viewing and imaging apparatus? (A) (B) (C) (D)

Output phosphor Beam splitter Spot image device Automatic brightness control

48. As electrons impinge on the anode sur ace, less than 1% o their kinetic energy is changed to (A) (B) (C) (D)

x-rays heat gamma rays recoil electrons

49. Which o the ollowing contribute(s) to inherent ltration? 1. X-ray tube glass envelope 2. X-ray tube port window 3. Aluminum between the tube housing and the collimator (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

50. A quality-control (QC) program includes checks on which o the ollowing radiographic equipment conditions? 1. Reproducibility 2. Linearity 3. Positive beam limitation/automatic collimation (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

51. What x-ray tube component does the Number 7 in Figure 5-4 indicate? (A) (B) (C) (D)

Anode stem Rotor Stator Focal track

Questions: 41–59

55. Disadvantages o moving grids over stationary grids include which o the ollowing?

3

4

265

5

1. T ey can prohibit the use o very short exposure times. 2. T ey increase patient radiation dose. 3. T ey can cause phantom images when anatomic parts parallel their motion.

2 6

7

8

1

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Figure 5-4.

52. Characteristics o x-ray photons include

56. T e unctions o a picture archiving and communication system (PACS) include

1. uorescent e ect on certain phosphors 2. physiological e ect on living tissue 3. characteristic negative electric charge

1. storage o analog images 2. reception o digital images 3. storage o digital images

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

53. All the ollowing x-ray circuit devices are located between the incoming power supply and the primary coil o the high-voltage trans ormer except (A) (B) (C) (D)

the timer the kilovoltage meter the milliamperage meter the autotrans ormer

54. Congruence o the x-ray beam with the light eld is tested using (A) (B) (C) (D)

a pinhole camera a star pattern radiopaque objects a slit camera

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

57. How many hal -value layers will it take to reduce an x-ray beam whose intensity is 78 R/min to an intensity o less than 20 R/min? (A) (B) (C) (D)

2 3 4 8

58. T e kV settings on radiographic equipment must be tested annually and must be accurate to within (A) (B) (C) (D)

+ /–2 kV + /–4 kV + /–6 kV + /–8 kV

59. T e device used to test the accuracy o the x-ray timer is the (A) (B) (C) (D)

densitometer sensitometer penetrometer spinning top

266

5: Equipment Operation and Quality Control

60. T e x-ray tube in a C imaging system is most likely to be associated with (A) (B) (C) (D)

low-energy photons an unrestricted x-ray beam a pulsed x-ray beam a large ocal spot

61. T e image shown in Figure 5-5 was made using an accurately calibrated (A) (B) (C) (D)

3ϕ 3ϕ 1ϕ 1ϕ

6P unit; 0.05 sec 6P unit; 0.10 sec unit, 0.05 sec unit; 0.10 sec

63. Exposures less than the minimum response time o an AEC may be required when 1. using high milliamperage 2. using ast imaging systems 3. examining large patients or body parts (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

64. Which o the ollowing in ormation is necessary to determine the maximum sa e kilovoltage using the appropriate x-ray tube rating chart? 1. Milliamperage and exposure time 2. Focal-spot size 3. Imaging-system speed (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

65. Which o the ollowing statements regarding dual x-ray absorptiometry is (are) true? 1. It is a low-dose procedure. 2. wo x-ray photon energies are used. 3. Photon attenuation by bone is calculated.

Figure 5-5.

62. Conditions that contribute to x-ray tube damage include 1. lengthy anode rotation 2. exposures to a cold anode 3. low-milliampere-seconds/high-kilovoltage exposure actors (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

(A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

66. A device used to ensure reproducible radiographs, regardless o tissue density variations, is the (A) (B) (C) (D)

automatic exposure control penetrometer grid device induction motor

67. T e device used to change alternating current to unidirectional current is (A) (B) (C) (D)

a capacitor a solid-state diode a trans ormer a generator

Questions: 60–76

68. I the distance rom the ocal spot to the center o the collimator’s mirror is 6 in, what distance should the illuminator’s light bulb be rom the center o the mirror? (A) (B) (C) (D) 69.

3 in 6 in 9 in 12 in

o maintain image clarity in an image-intensi er system, the path o electron ow rom the photocathode to the output phosphor is controlled by (A) (B) (C) (D)

the accelerating anode electrostatic lenses the vacuum glass envelope the input phosphor

70. T e ltering e ect o the x-ray tube’s glass envelope and its oil coolant are re erred to collectively as (A) (B) (C) (D)

inherent ltration added ltration compensating ltration port ltration

71. Which o the ollowing equipment is mandatory or per ormance o a myelogram? (A) Cine device (B) High- requency grid (C) ilting x-ray table (D) omography 72. Deposition o vaporized tungsten on the inner surace o the x-ray tube glass window

73. Which o the ollowing circuit devices operate(s) on the principle o sel -induction? 1. Autotrans ormer 2. Choke coil 3. High-voltage trans ormer (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

74. Which o the ollowing terms describes the amount o electric charge owing per second? (A) (B) (C) (D)

Voltage Current Resistance Capacitance

75. T e brightness level o the uoroscopic image can vary with 1. milliamperage 2. kilovoltage 3. patient thickness (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

76. Which o the ollowing does Figure 5-6 represent? (A) (B) (C) (D)

Compton scatter Bremsstrahlung radiation Photoelectric e ect Characteristic radiation

1. acts as additional ltration 2. results in increased tube output 3. results in anode pitting (A) (B) (C) (D)

267

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

N

Figure 5-6.

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5: Equipment Operation and Quality Control

77. T at portion o the remnant x-ray beam representing anatomical details having desirable quality is re erred to as (A) (B) (C) (D)

Photoelectric Compton Signal Noise

78. Component parts o a C imaging system include a(n) 1. high- requency generator 2. x-ray tube 3. operator console (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

79. All the ollowing are associated with the anode except (A) (B) (C) (D)

the line- ocus principle the heel e ect the ocal track thermionic emission

82. Which part o an induction motor is located outside the x-ray tube glass envelope? (A) (B) (C) (D)

83. Moving the image intensi er closer to the patient during uoroscopy 1. decreases the SID 2. decreases patient dose 3. improves image quality (A) (B) (C) (D)

(A) (B) (C) (D)

inverse-square law line- ocus principle reciprocity law anode heel e ect

1

Filament Focusing cup Stator Rotor

81. A technique chart should be prepared or each AEC x-ray unit and should contain which o the ollowing in ormation or each type o examination? 1. Photocell(s) used 2. Optimum kilovoltage 3. Backup time (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

84. Figure 5-7 illustrates the

80. Which part o an induction motor is located within the x-ray tube glass envelope? (A) (B) (C) (D)

Filament Focusing cup Stator Rotor

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

2

Figure 5-7.

85. Although the stated ocal-spot size is measured directly under the actual ocal spot, ocal-spot size actually varies along the length o the x-ray beam. At which portion o the x-ray beam is the e ective ocal spot the smallest? (A) (B) (C) (D)

At its outer edge Along the path o the central ray At the cathode end At the anode end

Questions: 77–93

86. T e total brightness gain o an image intensi er is the product o 1. ux gain 2. mini cation gain 3. ocusing gain (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1 and 3 only

87. Which o the ollowing is/are associated with magni cation uoroscopy? 1. Higher patient dose than nonmagni cation uoroscopy 2. Higher voltage to the ocusing lenses 3. Image intensi er ocal point closer to the input phosphor (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

88. Advantages o battery-powered mobile x-ray units include their 1. ability to store a large quantity o energy 2. ability to store energy or extended periods o time 3. lightness and ease o maneuverability (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

89. Which o the ollowing modes o a tri eld image intensi er will result in the highest patient dose? (A) (B) (C) (D)

Its 25-in mode Its 17-in mode Its 12-in mode Diameter does not a ect patient dose

269

90. O - ocus, or extra ocal, radiation is minimized by (A) avoiding the use o very high kilovoltages (B) restricting the x-ray beam as close to its source as possible (C) using compression devices to reduce tissue thickness (D) avoiding extreme collimation 91. Which o the ollowing is/are components o the secondary, or high voltage, side o the x-ray circuit? 1. Recti cation system 2. Autotrans ormer 3. kV meter (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

92. An AEC device can operate on which o the ollowing principles? 1. A photomultiplier tube charged by a uorescent screen 2. A parallel-plate ionization chamber charged by x-ray photons 3. Motion o magnetic elds inducing current in a conductor (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

93. Which o the ollowing unctions to increase the milliamperage? (A) (B) (C) (D)

Increase in charge o anode Increase in heat o the lament Increase in kilovoltage Increase in ocal-spot size

270

5: Equipment Operation and Quality Control

94. I 92 kV and 15 mAs were used or a particular abdominal exposure with single-phase equipment, what milliampere-seconds value would be required to produce a similar radiograph with three-phase, 12-pulse equipment? (A) (B) (C) (D)

36 24 10 7.5

95. Fractional- ocus tubes, with a 0.3-mm ocal spot or smaller, have special application in (A) magni cation radiography (B) uoroscopy (C) tomography (D) image intensi cation

A

96. In the radiographic rating charts shown in Figure 5-8, what is the maximum sa e kilovoltage that may be used with the 1.0-mm ocal-spot, single-phase x-ray tube using 400-mA and a 0.02-s exposure? (A) (B) (C) (D)

70 kV 75 kV 80 kV 85 kV B

C

Figure 5-8. Reproduced, with permission, from Dunlee Tech Data Publication 50014.

Questions: 94–104

97. In Figure 5-8, which o the illustrated x-ray tubes permit(s) an exposure o 400 mA, 0.1 s, and 80 kV? 1. ube A 2. ube B 3. ube C (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

98. In Figure 5-8, what is the maximum sa e milliamperage that may be used with a 0.10-s exposure and 120 kV, using the three-phase, 1.0-mm ocal-spot x-ray tube? (A) (B) (C) (D)

300 mA 400 mA 500 mA 600 mA

99. Re erring to the anode cooling chart in Figure 5-9, i the anode is saturated with 300,000 heat units (HU), how long will the anode need to cool be ore another 160,000 HU can be sa ely applied? (A) (B) (C) (D)

3 minutes 4 minutes 5 minutes 7 minutes

271

100. A three-phase timer can be tested or accuracy using a synchronous spinning top. T e resulting image looks like a (A) series o dots or dashes, each representative o a radiation pulse (B) solid arc, with the angle (in degrees) representative o the exposure time (C) series o gray tones, rom white to black (D) multitude o small, mesh-like squares o uni orm sharpness 101. Anode angle will have an e ect on the 1. severity o the heel e ect 2. ocal-spot size 3. heat-load capacity (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

102. T e minimum response time o an automatic exposure control (AEC) (A) is the time required to energize the intensi ying phosphors (B) is its shortest possible exposure time (C) unctions to protect the patient rom overexposure (D) unctions to protect the tube rom excessive heat 103. All the ollowing statements regarding mobile radiographic equipment are true except (A) exposure switches must be the “dead man” type (B) the radiographer must alert individuals in the area be ore making the exposure (C) the exposure cord must permit the operator to stand at least 4 f rom the patient, x-ray tube, and use ul beam (D) a lead apron should be carried with the unit and worn by the radiographer during exposure 104. Which o the ollowing is most closely related to Figure 5-10?

Figure 5-9. Reproduced, with permission, from Dunlee Tech Data Publication 50014.

(A) (B) (C) (D)

low kV high kV low mA high mA

272

5: Equipment Operation and Quality Control

108. Which o the ollowing combinations will o er the greatest heat-loading capability? (A) (B) (C) (D)

17-degree target angle, 1.2-mm actual 10-degree target angle, 1.2-mm actual 17-degree target angle, 0.6-mm actual 10-degree target angle, 0.6-mm actual

ocal spot ocal spot ocal spot ocal spot

109. Which o the ollowing would be appropriate IP ront material(s)?

Figure 5-10.

105. Which o the ollowing ormulas would the radiographer use to determine the total number o heat units produced with a given exposure using threephase, six-pulse equipment? (A) (B) (C) (D)

mA × mA × mA × mA ×

time × time × time × time ×

kV kV × 0.6 kV × 1.2 kV × 1.4

106. T e voltage across the x-ray tube in three-phase equipment 1. drops to zero every 180 degrees 2. is 87% to 96% o the maximum value 3. is at nearly constant potential (A) (B) (C) (D)

1 only 2 only 1 and 2 only 2 and 3 only

1. ungsten 2. Magnesium 3. Bakelite (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

110. How of en are radiographic equipment kV settings required to be evaluated? (A) (B) (C) (D)

Annually Biannually Semiannually Quarterly

111. What x-ray tube component does the Number 7 in Figure 5-11 indicate? (A) (B) (C) (D)

Anode stem Rotor Stator Focal track

107. Images using a particular single-phase, ull-waverecti ed x-ray unit were made, using known correct exposures. A spinning-top test was per ormed at 200 mA, 0.05 s, and 70 kV, and 8 dots were visualized. Which o the ollowing is indicated? (A) (B) (C) (D)

3

4 5

T e 0.05-s time station is inaccurate. T e 200-mA station is inaccurate. A recti er is not unctioning. T e processor needs servicing.

2 6

7

8

1

Figure 5-11.

Questions: 105–120

112. T e image-intensi er tube’s input phosphor unctions to convert (A) kinetic energy to light (B) x-rays to light (C) electrons to light (D) uorescent light to electrons 113. Accurate operation o the AEC device depends on 1. tissue thickness and density 2. positioning o the object with respect to the photocell 3. beam restriction (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

114. T e image intensi er’s input phosphor generally is composed o (A) (B) (C) (D)

cesium iodide zinc cadmium sul de gadolinium oxysul de calcium tungstate

115. T e total number o x-ray photons produced at the target is contingent on the 1. tube current 2. target material 3. square o the kilovoltage (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

116. A photostimulable phosphor plate is used with (A) CR (B) radiographic intensi ying screens (C) uoroscopic intensi ying screens (D) image-intensi ed uoroscopy

273

117. X-ray tubes used in C imaging systems must be capable o 1. high short-exposure rating 2. tolerating millions o heat units 3. high-speed anode rotation (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

118. An incorrect relationship between the primary beam and the center o a ocused grid results in 1. an increase in scattered radiation production 2. grid cuto 3. insu cient receptor exposure (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

119. QA was being per ormed on a three-phase, ull-wave-recti ed x-ray unit. A synchronous spinning-top test was per ormed using 300 mA, 60 ms, and 70 kV. A 22-degree arc is observed on the test image. Which o the ollowing statements regarding these results is most correct? (A) (B) (C) (D)

T e timer is inaccurate. T e milliamperage station is inaccurate. One recti er is mal unctioning. T e test results are satis actory.

120. Which o the ollowing will most likely produce the highest quality radiographic image? (A) (B) (C) (D)

high SNR low SNR low contrast resolution moderate noise

Answers and Explanations

1. (A) Quality Control re ers to our equipment and its sa e and accurate operation. Various components must be tested at speci ied intervals and test results must be within speci ied parameters. Any deviation rom those parameters must be corrected. Examples o equipment components that are tested annually are the ocal-spot size, linearity, reproducibility, iltration, kV, and exposure time. Reproducibility speci ies that radiation output must be consistent to within + /–5%. Linearity tests x-ray output with increasing mAs; mR/mAs should be accurate to within 10%. Kilovoltage settings can most e ectively be tested using an electronic kV meter; to meet required standards, the kV should be accurate to within + /–4 kV. Congruence is a term used to describe the relationship between the collimator light ield and the actual x-ray ield—they must be congruent to within 2% o the SID. Radiographic equipment collimators should be inspected and veri ied as accurate semiannually. 2. (B) wo types o interactions between high-speed incident electrons and the tungsten-target atoms account or the production o x-rays within the x-ray tube. (1) In the production o Brems (“braking”) radiation, a high-speed electron is attracted to the positive nuclear charge o a tungsten atom. In doing so, it is “braked” and gives up energy in the orm o an x-ray photon. Most o the primary beam is made up o Brems radiation. (2) I the incident electron were to eject a K-shell electron, an L-shell electron would move in to ll the vacancy. It releases a photon (K-characteristic ray) whose energy equals the di erence between the

274

K- and L-shell energy levels. T is is characteristic radiation; it is responsible or only a small portion o the primary beam. 3. (D) C (Computed omography), MRI (Magnetic Resonance Imaging), and CR (Computed Radiography) are three common examples o digital imaging. Special equipment is also available or direct digital radiography (DR)—images produced by either a an-shaped x-ray beam received by linearly arrayed radiation detectors or a traditional anshaped x-ray beam received by a light-stimulated phosphor plate. Digital images can also be obtained in digital subtraction angiography (DSA), nuclear medicine, and diagnostic sonography. Analog images are conventional images; they can be converted to digital images with a device called a digitizer. 4. (D) A C imaging system has three component parts—a gantry, a computer, and an operating console. T e gantry component includes an x-ray tube, a detector array, a high-voltage generator, a collimator assembly, and a patient couch with its motorized mechanism. Although the C x-ray tube is similar to direct-projection x-ray tubes, it has several special requirements. T e C x-ray tube must have a very high short-exposure rating and must be capable o tolerating several million heat units while still having a small ocal spot or optimal resolution. o help tolerate the very high production o heat units, the anode must be capable o high-speed rotation. T e x-ray tube produces a pulsed x-ray beam (1–5 ms) using up to about 1,000 mA. T e scintillation detector array is made o thousands o

Answers: 1–8

solid-state photodiodes. T ese scintillation crystal photodiode assemblies (cadmium tungstate or rare earth oxide ceramic crystals) convert the transmitted x-ray energy into light. T e light then is converted into electrical energy and nally into an electronic/digital signal. I the scintillation crystals are packed tightly together so that there is virtually no distance between them, e ciency o x-ray absorption is increased, and patient dose is decreased. Detection e ciency is extremely high— approximately 90%. T e high-voltage generator provides high- requency power to the C x-ray tube, enabling the high-speed anode rotation and the production o high-energy pulsed x-ray photons. Similar to the high- requency x-ray tubes used in projection radiography, conventional 60-Hz ull-wave-recti ed power is converted to a higher requency o 500 to 25,000 Hz. T e high- requency generator is small in size, in addition to producing an almost constant potential wave orm. T e C high- requency generator is of en mounted in the gantry’s rotating wheel. T e collimator assembly has two parts: T e prepatient, or predetector, collimator is at the x-ray tube and consists o multiple beam restrictions so that the x-ray beam diverges little. T is reduces patient dose and reduces the production o scattered radiation, thereby improving the C image. T e postpatient collimator, or predetector collimator, con nes the exit photons be ore they reach the detector array and determines slice thickness. T e patient table, or couch, provides positioning support or the patient. Its motorized movement should be smooth and accurate. Inaccurate indexing can result in missed anatomy and/or doubleexposed anatomy. 5. (D) Each time an x-ray exposure is made, less than 1% o the total energy is converted to x-rays, and the remainder (>99%) o the energy is converted to heat. T us, it is important to use target material with a high atomic number and high melting point. T e larger the actual ocal-spot size, the larger is the area over which the generated heat is spread, and the more tolerant the x-ray tube is. Heat is particularly damaging to the target i it is concentrated or limited to a small area. A target that rotates during the exposure is spreading the heat over a large area, the entire sur ace o the ocal track. I the diameter o the anode is greater, the ocal track will be longer, and heat will be spread over an even larger area.

275

6. (D) Determining milliroentgens per milliampere-seconds output is of en done to determine linearity among x-ray machines. However, all the equipment being compared must be o the same type (e.g., all single-phase or all three-phase, six-pulse). I there is linearity among these machines, then identical technique charts can be used. In the example given, 400 mA and 12 ms were used, equaling 4.8 mAs. I the output or 4.8 mAs was 150 mR, then 1 mAs is equal to 31.25 mR (150 mR ÷ 4.8 mAs = 31.25 mR/mAs). 7. (B) T e high-voltage, or step-up, trans ormer unctions to increase voltage to the necessary kilovoltage. It decreases the amperage to milliamperage. T e amount o increase or decrease depends on the trans ormer ratio—the ratio o the number o turns in the primary coil to the number o turns in the secondary coil. T e trans ormer law is as ollows: o determine secondary V, Vs N s = Vp N p o determine secondary I, Ns I p = N p Is Substituting known actors: x 50,000 = 220 100 100x = 11,000,000 x = 110,000 V(110 kV) 50,000 100 = 100 x 50,000x = 10,000 x = 0.2 A(200 mA) 8. (C) Seven wave orms are illustrated. Wave orm A represents alternating current. Wave orm B illustrates hal -wave recti cation; each use ul pulse (o x-ray) is ollowed by a pause o equal length. Figure C illustrates ull-wave recti cation. Note the 100% voltage ripple as each pulse starts at 0 potential, makes its way to 100%, and returns to 0 potential. Wave orm D represents three-phase, six-pulse current exhibiting a 13% voltage drop between peak potentials. Wave orm E represents three-phase, 12-pulse current having only about a 4% voltage drop between peak potentials. A big advantage o

276

5: Equipment Operation and Quality Control

three-phase current is the very small drop in voltage between pulses. Wave orm F illustrates high- requency current, which is most e cient and produces less than 1% voltage ripple. Here, 60-Hz ull-wave-recti ed current is converted to higher requency (500–25,000 Hz). Mobile x-ray units rst used this technology, because one o its greatest advantages is its small size. High- requency generators are also used in mammography units and helical C . More and more traditional x-ray equipment is using high- requency technology because o its compact size, lower cost, and greater e ciency. 9. (A) When a dual- eld image intensi er is switched to the smaller eld, the electrostatic ocusing lenses are given a greater charge to ocus the electron image more tightly. T e ocal point, then, moves urther rom the output phosphor (the diameter o the electron image is, there ore, smaller as it reaches the output phosphor), and the brightness gain is somewhat diminished. Hence, the patient area viewed is somewhat smaller and is magni ed. However, the mini cation gain has been reduced, and the image is somewhat less bright. 10. (A) AECs are used in today’s equipment and serve to produce consistent and comparable results. In one type o AEC, there is an ionization chamber beneath the tabletop above the IR. T e part to be examined is centered to it (the sensor) and radiographed. When a predetermined quantity o ionization has occurred (equal to the correct receptor exposure), the exposure terminates automatically. With the second type o AEC, the phototimer, a small uorescent screen, is positioned beneath the cassette. When remnant radiation emerging rom the patient exposes the IR and exits, the uorescent screen emits light. Once a predetermined amount o uorescent light has been “seen” by the photocell sensor, the exposure is terminated automatically. In either case, the manual timer should be used as a backup timer; in case o AEC mal unction, the exposure would terminate, thus avoiding patient overexposure and tube overload. 11. (B) T e thoriated tungsten lament o the cathode is heated by its own lament circuit. T e x-ray tube lament is made o thoriated tungsten and is part o

the cathode assembly. Its circuit provides current and voltage to heat it to incandescence, at which time it undergoes thermionic emission—the liberation o valence electrons rom the lament atoms. Electrolysis describes the chemical ionization e ects o an electric current. Recti cation is the process o changing alternating current to unidirectional current. 12. (B) An image’s spatial resolution re ers to its recorded detail. T e e ect o the input screen’s phosphor layer is similar to the e ect o the phosphor layer thickness in intensi ying screens; that is, as the phosphor layer is made thinner, recorded detail increases. Also, the smaller the input phosphor diameter, the greater is the spatial resolution. A brighter image is easier to see but does not a ect resolution. 13. (D) Anode target material with a high atomic number produces higher-energy x-rays more e ciently. Because a great deal o heat is produced at the target, the material should have a high melting point so as to avoid damage to the target sur ace. Most o the x-rays generated at the ocal spot are directed downward and pass through the x-ray tube’s port window. T e cathode lament receives low-voltage current to heat it to the point o thermionic emission. T en, high voltage is applied to drive the electrons across to the ocal track. 14. (A) A parallel-plate ionization chamber is a type o AEC. A radiolucent chamber is beneath the patient (between the patient and the IR). As photons emerge rom the patient, they enter the chamber and ionize the air within it. Once a predetermined charge has been reached, the exposure is terminated automatically. 15. (C) As ltration is added to the x-ray beam, the lower-energy photons are removed, and the overall energy or wavelength o the beam is greater. As kilovoltage is increased, more high-energy photons are produced, and again, the overall, or average, energy o the beam is greater. An increase in milliamperage serves to increase the number o photons produced at the target but is unrelated to their energy. 16. (A) Radiographic rating charts enable the operator to determine the maximum sa e milliamperage,

Answers: 9–22

exposure time, and kilovoltage or a particular exposure using a particular x-ray tube. An exposure that can be made sa ely with the large ocal spot may not be sa e or use with the small ocal spot o the same x-ray tube. T e total number o heat units that an exposure generates also in uences the amount o stress (in the orm o heat) imparted to the anode. T e product o milliampere-seconds and kilovoltage determines heat units. Group (A) produces 138 HU, group (B) produces 240 HU, group (C) produces 420 HU, and group (D) produces 720 HU. T e least hazardous group o technical actors is, there ore, group (A). Group (A) is also delivering its heat to the large ocal spot, thereby decreasing the heat load to the anode. 17. (C) T e gure illustrates the component parts o a rotating-anode x-ray tube enclosed within a glass envelope (Number 3) to preserve the vacuum necessary or x-ray production. Number 4 is the rotating anode with its beveled ocal track at the periphery (Number 8) and its stem (at Number 5). Numbers 6 and 7 are the stator and rotor, respectively—the two components o an induction motor—whose unction is to rotate the anode. Number 1 is the lament o the cathode assembly, which is made o thoriated tungsten and unctions to liberate electrons (thermionic emission) when heated to white hot (incandescence). Number 2 is the nickel ocusing cup, which unctions to direct the liberated lament electrons to the ocal spot. 18. (A) Parts being examined during uoroscopic procedures change in thickness and density as the patient is required to change positions and as the uoroscope is moved to examine di erent regions o the body that have varying thickness and tissue densities. T e automatic brightness control unctions to vary the required milliampereseconds and/or kilovoltage as necessary. With this method, patient dose varies, and image quality is maintained. Mini cation and ux gain contribute to total brightness gain. 19. (C) A large quantity o heat applied to a cold anode can cause enough sur ace heat to crack the anode. Excessive heat to the target can cause pitting or localized melting o the ocal track. Localized melts can result in vaporized tungsten deposits on the

277

glass envelope, which can cause a ltering e ect, decreasing tube output. Excessive heat also can be conducted to the rotor bearings, causing increased riction and tube ailure. 20. (B) T e high-voltage, or step-up, trans ormer unctions to increase voltage to the necessary kilovoltage. It decreases the amperage to milliamperage. T e amount o increase or decrease depends on the trans ormer ratio, that is, the ratio o the number o turns in the primary coil to the number o turns in the secondary coil. T e trans ormer law is as ollows: o determine secondary V, Vs N s = Vp N p o determine secondary I, Ns I p = N p Is Substituting known values: x 100,000 = 220 400 400x = 22,000,000 T us, x = 55,000 V (55 kV). 21. (A) T e HVL o a particular beam is de ned as that thickness o a material that will reduce the exposure rate to one-hal o its original value. T e more energetic the beam (the higher the kilovoltage), the greater is the HVL thickness required to cut its intensity in hal . T ere ore, it may be stated that kilovoltage and HVL have a direct relationship: As kilovoltage increases, HVL increases. 22. (C) In electronic/digital imaging, changes in window width a ect changes in contrast scale, while changes in window level a ect changes in brightness. As window width increases, the scale o contrast increases (i.e., contrast decreases). As window level increases, brightness increases. T is process can also be illustrated while postprocessing/windowing personal digital photographs or scanned documents. 23. (A) Recti ers change AC into unidirectional current by allowing current to ow through them in only one direction. Valve tubes are vacuum rectier tubes ound in older equipment. Solid-state diodes are the types o recti ers used in today’s

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5: Equipment Operation and Quality Control

x-ray equipment. Recti cation systems are ound between the secondary coil o the high-voltage trans ormer and the x-ray tube. Resistors, such as rheostats or choke coils, are circuit devices used to vary voltage or current. rans ormers, operating on the principle o mutual induction, change the voltage (and current) to use ul levels. Autotrans ormers, operating on the principle o sel -induction, enable us to select the required kilovoltage. 24. (D) Moving the image intensi er closer to the patient during uoroscopy decreases the SID and patient dose (as SID is reduced, the intensity o the x-ray photons at the image intensi er’s input phosphor increases; the automatic brightness control then automatically decreases the milliamperage and, there ore, patient dose). Moving the image intensi er closer to the patient during uoroscopy also decreases the OID and, there ore, magni cation. As tissue density increases, a greater exposure dose is required. 25. (B) When an AEC is installed in an x-ray circuit, it is calibrated to produce radiographic densities as required by the radiologist. Once the part being radiographed has been exposed to produce the correct receptor exposure, the AEC automatically terminates the exposure. T e manual timer should be used as a backup timer; in case the AEC ails to terminate the exposure, the backup timer would protect the patient rom overexposure and the x-ray tube rom excessive heat load. T e master receptor exposure override generally is set on normal to produce the required receptor exposure. In special cases, when this produces excessive or insu cient receptor exposure, the master receptor exposure override may be adjusted to plus or minus position. 26. (B) A generator converts mechanical energy into electrical energy—as alternating or direct current. A motor is a device used to convert electrical energy to mechanical energy. T e stator and rotor are the two principal parts o an induction motor. 27. (C) A phototimer is a type o AEC that is used to automatically terminate the x-ray exposure once the IR is correctly exposed. Another type o AEC is the ionization chamber. An image intensi er unctions to provide a brighter uoroscopic image, and positive beam limitation (PBL), or

automatic collimation, serves to restrict the eld size to the size o the cassette/IR used in the Bucky tray. T e line-voltage compensator automatically adjusts the incoming line voltage to the x-ray machine to correct or any voltage drops or surges. 28. (B) A quality-control (QC) program requires the use o a number o devices to test the e ciency o various parts o the imaging system. Spatial resolution is most signi cantly a ected by the ocalspot size. A slit camera, as well as a star pattern (Fig. 5-12), or pinhole camera, is used to test ocal-spot size. T e slit camera is considered the standard or (annual) measurement o the e ective ocal-spot size. A parallel line–type resolution test pattern (Fig. 5-12) can be used to test the resolution capability o intensi ying screens. 29. (D) Because mammography uses such lowkilovoltage levels, IR ront material becomes especially important. Any attenuation o the beam by the IR ront would be most undesirable. Lowattenuating carbon bers or special plastics that resist impact and heat sof ening (e.g., polystyrene and polycarbonate) are used requently as IR ront material. 30. (D) As the lament ages, vaporized tungsten may be deposited on the port window and act as an additional lter. ungsten may also vaporize as a result o anode abuse. Exposures in excess o sa e values deliver su cient heat to cause sur ace melts, or pits, on the ocal track. T is results in roughening o the anode sur ace and decreased tube output. Delivery o a large amount o heat to a cold anode can cause cracking i the anode does not have su cient time to disperse the heat. Loss o anode rotation would cause one large melt on the ocal track because the electrons would bombard only one small area. I the anode is not heard to be rotating, the radiographer should not make an exposure. 31. (B) T ere are three types o beam restrictors— aperture diaphragms, cones and cylinders, and collimators. T e most practical and e cient type is the collimator. Its design makes available an in nite number o eld-size variations that are not available with the other types o beam restrictors. Because aperture diaphragms and are cones have a xed aperture size and shape, their beam

Answers: 24–33

279

Figure 5-12. Courtesy of Nuclear Associates.

restriction is not as e cient as that o the variable size collimator. Aperture diaphragms, cones, and cylinders may be placed on a collimator track so that the illuminated crosshairs are visualized. Although the collimator assembly contributes approximately 1.0-mm Al equivalent to the added ltration o the x-ray tube (because o the plastic exit portal and silver-coated re ective mirror), its unctions are unrelated to the cleanup o scattered radiation. T is is so because the patient is the principal scatterer, and grids unction to clean up scattered radiation generated by the patient. 32. (B) X-ray tubes are diode tubes; that is, they have two electrodes—a positive electrode called the anode and a negative electrode called the cathode. T e cathode lament is heated to incandescence and releases electrons—a process called thermionic emission. During the exposure, these electrons are driven by thousands o volts toward the anode,

where they are suddenly decelerated. T at deceleration is what produces x-rays. Some x-ray tubes, such as those used in uoroscopy, digital radiography, and DSA, are required to make short, precise—sometimes multiple—exposures. T is need is met by using a grid-controlled tube. A grid-controlled tube uses the molybdenum ocusing cup as the switch, permitting very precise control o the tube current ( ow o electrons between cathode and anode). 33. (D) T e x-ray anode may be a molybdenum disk coated with a tungsten–rhenium alloy. Because tungsten has a high atomic number (74), it produces high-energy x-rays more e ciently. Since a great deal o heat is produced at the target, tungsten’s high melting point (3,410°C) helps to avoid damage to the target sur ace. Heat produced at the target should be dissipated readily, and tungsten’s conductivity is similar to that o copper. T ere ore, as heat

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is applied to the ocus, it can be conducted throughout the disk to equalize the temperature and thus avoid pitting, or localized melting, o the ocal track. 34. (B) AEC devices are used in today’s equipment and serve to produce consistent and comparable radiographic results. In one type o AEC, an ionization chamber (Figure A) is located just beneath the tabletop above the IR. T e part to be examined is centered to the AEC’s sensor and imaged. When a predetermined quantity o ionization has occurred (equal to the correct receptor exposure), the x-ray exposure terminates automatically. In the phototimer-type AEC (Figure B), a small uorescent screen is positioned beneath the IR. When remnant radiation emerging rom the patient exposes and exits the IR, the uorescent screen emits light. Once a predetermined amount o uorescent light is measured by the photocell sensor, the exposure is terminated. A special IR, one without lead oil backing, is of en required with this type o AEC. In either case, the manual timer should be used as a backup timer. In case o AEC mal unction, this would terminate the exposure, thus avoiding patient overexposure and x-ray tube overload. 35. (B) Voltage ripple re ers to the percentage drop rom maximum voltage each pulse o current experiences. In single-phase recti ed equipment, the entire pulse (hal -cycle) is used; there ore, there is rst an increase to the maximum (peak) voltage value and then a decrease to zero potential (90-degree past peak potential). T e entire waveorm is used; at 100 kV, the actual average kilovoltage output would be approximately 70 kV. T ree-phase recti cation produces almost constant potential, with small ripples (drops) in maximum potential between pulses. Approximately a 13% voltage ripple (drop rom maximum value) characterizes the operation o three-phase, six-pulse generators. T ree-phase, 12-pulse generators have about a 4% voltage ripple. High- requency current is most e cient and produces less than 1% voltage ripple. T e high- requency generator is small in size and produces an almost constant potential wave orm. 36. (C) T e visual apparatus that is responsible or visual acuity and contrast perception is the cones

within the retina. Cones are also used or daylight vision. T ere ore, the most desirable condition or uoroscopic viewing is to have a bright enough image to permit cone (daylight) vision or better detail perception. T e image intensi er accomplishes this. T e intensi ed image is then transerred to a V monitor or viewing. Cine and spot image devices can be used to record uoroscopic events. 37. (A) T e incident electron has a certain amount o energy as it approaches the tungsten target. I the positive nucleus o a tungsten atom attracts the electron, changing its course, a certain amount o energy is released during the “braking” action. T is energy is given up in the orm o an x-ray photon called Bremsstrahlung (“braking”) radiation. Characteristic radiation is also produced at the target (less requently) when an incident electron ejects a K-shell electron, and an L-shell electron drops into its place. Energy is liberated in the orm o a characteristic ray, and its energy is representative o the di erence in energy levels. Compton scatter and the photoelectric e ect are interactions between x-ray photons and tissue atoms. 38. (C) T e input phosphor o an image intensi er receives remnant radiation emerging rom the patient and converts it to a uorescent light image. Directly adjacent to the input phosphor is the photocathode, which is made o a photoemissive alloy (usually, a cesium and antimony compound). T e uorescent light image strikes the photocathode and is converted to an electron image. T e electrons are ocused care ully, to maintain image resolution, by the electrostatic ocusing lenses, through the accelerating anode and to the output phosphor or conversion back to light. T e V monitor is not part o the image intensi er but serves to display the image that is transmitted to it rom the output phosphor. 39. (B) In digital imaging, x-rays orm an electronic image on a special radiation detector. T is electronic image can be manipulated by a computer and stored in the computer memory or displayed as a matrix o intensities. T is nal digital image is of en viewed on a computer monitor and looks very much like an x-ray lm image, but the computer has the capability o postprocessing image enhancement.

Answers: 34–46

40. (B) In digital uoroscopy (DF), the image-intensier output screen image is coupled via a chargecoupled device (CCD) or viewing on a display monitor. A CCD converts visible light to an electrical charge that is then sent to the analog-to-digital converter (ADC) or processing. When output screen light strikes the CCD cathode, a proportional number o electrons are released by the cathode and stored as digital values by the CCD. T e CCD’s rapid discharge time virtually eliminates image lag and is particularly use ul in high-speed imaging procedures such as cardiac catheterizations. CCD cameras have replaced analog cameras (such as the Vidicon and Plumbicon) in new uoroscopic equipment. CCDs are more sensitive to the light emitted by the output phosphor (than the analog cameras) and are associated with less “noise.” DF photo-spot images are simply still- rame images and, in comparison to lm images, need no chemical processing, require less patient dose, and o er postprocessing capability. DF also o ers “road-mapping” capability. “Road-mapping” is a technique use ul in procedures involving guidewire/catheter placement. During the uoroscopic examination, the most recent uoroscopic image is stored on the monitor, thereby reducing the need or continuous x-ray exposure. T is technique can o er signi cant reductions in patient and personnel radiation exposure. 41. (C) T e autotrans ormer operates on the principle o sel -induction and unctions to select the correct voltage to be sent to the high-voltage trans ormer to be “stepped up” to kilovoltage. T e high-voltage trans ormer increases the voltage and decreases the current. T e rheostat is a type o variable resistor that is used to change voltage or current values. It is ound requently in the lament circuit. A use is a device used to protect the circuit elements rom overload by opening the circuit in the event o a power surge. 42. (C) Quality Control re ers to our equipment and its sa e and accurate operation. Various components must be tested at speci ed intervals and test results must be within speci ed parameters. Any deviation rom those parameters must be corrected. Examples o equipment components that are tested annually are the ocal-spot size, linearity, reproducibility, collimation, ltration, kV, and exposure time. Quality Assurance is associated with patients and sta , and their interactions and relationships.

281

Congruence is a term used to describe the relationship between the collimator light eld and the actual x-ray eld—they must be congruent (i.e., match) to within 2% o the SID. Postprocessing re ers to the windowing or other manipulation o a digital image. 43. (C) Structures that we wish to visualize requently are superimposed on other structures o lesser interest. omography uses reciprocal motion between the x-ray tube and the IR to image structures at a particular level in the body while blurring everything above and below that level. T e thickness o the level visualized can be changed by changing the tube angle (amplitude). T e greater the tube angle, the thinner is the section imaged. 44. (A) As body areas o di erent thicknesses and densities are scanned with the image intensi er, image brightness, and contrast require adjustment. T e ABC unctions to maintain constant brightness and contrast o the output screen image, correcting or uctuations in x-ray beam attenuation with adjustments in kilovoltage and/ or milliamperage. T ere are also brightness and contrast controls on the monitor that the radiographer can regulate. 45. (B) Because the high-voltage trans ormer has a xed ratio, there must be a means o changing the voltage sent to its primary coil; otherwise, there would be a xed kilovoltage. T e autotrans ormer makes these changes possible. When kilovoltage is selected on the control panel, the radiographer actually is adjusting the autotrans ormer and selecting the amount o voltage to send to the high-voltage trans ormer to be stepped up (to kilovoltage). T e lament circuit supplies the proper current and voltage to the x-ray tube lament or proper thermionic emission. T e recti er circuit is responsible or changing AC to unidirectional current. 46. (B) T e terms star and wye (or delta) re er to the con guration o trans ormer windings in threephase equipment. Instead o having a single primary coil and a single secondary coil, the high-voltage trans ormer has three primary and three secondary windings—one winding or each phase (Fig. 5-13). Autotrans ormers operate on the principle o sel -induction and have only one

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S e conda ry high volta ge coil (s ta r/wye winding) P rima ry high volta ge coil (de lta winding)

Thre e -pha s e tra ns forme r

Re ctifie rs

Figure 5-13.

winding. T ree-phase x-ray equipment of en has three autotrans ormers. 47. (B) T e light image emitted rom the output phosphor o the image intensi er is directed to the V monitor or viewing and sometimes to recording devices such as a spot image or cine device. T e light is directed to these places by a beam splitter or objective lens located between the output phosphor and the V camera tube (or CCD). T e majority o the light will go to the recording device, whereas a small portion goes to the monitor so that the procedure may continue to be observed during imaging. 48. (A) T e vast majority o target interactions involve the incident electrons and outer-shell tungsten electrons. No ionization occurs, and the energy loss is re ected in heat generation. T e production o x-rays is an amazingly ine cient process: More than 99% o the electrons’ kinetic energy is changed to heat energy and less than 1% into x-ray photon energy. T is presents a serious heat-buildup problem in the anode because heat production is directly proportional to tube current. 49. (B) Inherent ltration is that which is “built into” the construction o the x-ray tube. Be ore exiting the x-ray tube, x-ray photons must pass through the tube’s glass envelope and port window; the photons are ltered somewhat as they do so. T is inherent ltration is usually the equivalent o 0.5 mm Al. Aluminum ltration placed between the x-ray tube housing and the collimator is added to contribute to

the total necessary requirement o 2.5-mm Al equivalent. T e collimator itsel is considered part o the added ltration (1.0-mm Al equivalent) because o the silver sur ace o the mirror within. It is important to remember that as aluminum ltration is added to the x-ray tube, the HVL increases. 50. (D) T e accuracy o all three is important to ensure adequate patient protection. Reproducibility means that repeated exposures using given technical actors must provide consistent intensity. Linearity means that a given milliampere-seconds value, using di erent milliamperage stations with appropriate exposure time adjustments, will provide consistent intensity. PBL is automatic collimation and must be accurate to 2% o the SID. Light-localized collimators must be available and must be accurate to within 2%. 51. (B) T e gure illustrates the component parts o a rotating-anode x-ray tube enclosed within a glass envelope (Number 3) to preserve the vacuum necessary or x-ray production. Number 4 is the rotating anode with its beveled ocal track at the periphery (Number 8) and its stem (at Number 5). Numbers 6 and 7 are the stator and rotor, respectively—the two components o an induction motor—whose unction is to rotate the anode. Number 1 is the lament o the cathode assembly, which is made o thoriated tungsten and unctions to liberate electrons (thermionic emission) when heated to white hot (incandescence). Number 2 is the molybdenum ocusing cup, which unctions to direct the liberated lament electrons to the ocal

Answers: 47–57

spot. Aliasing, or Moiré, has the appearance o somewhat wavy linear lines and can occur in computed radiography when using stationary grids. 52. (B) X-rays are energetic enough to rearrange atoms in materials through which they pass, and they can, there ore, be hazardous to living tissue. X-rays are called ionizing radiation because they have the energetic potential to break apart electrically neutral atoms, resulting in the production o negative and/or positive ions. X-rays are in nitesimal bundles o energy called photons that deposit some o their energy into matter as they travel through it. T is deposition o energy and subsequent ionization has the potential to cause chemical and biologic damage. Several o the outstanding properties o x-ray photons are: • • • • • • • • • • • •

X-rays are not perceptible by the senses. X-rays travel in straight lines. X-rays travel at the speed o light. X-rays are electrically neutral. X-rays have a penetrating e ect on all matter. X-rays have a physiological e ect on living tissue. X-rays have an ionizing e ect on air. X-rays have a photographic e ect on lm emulsion. X-rays produce uorescence in certain phosphors. X-rays cannot be ocused. X-rays have a spectrum o energies. X-rays are una ected by a magnetic eld.

53. (C) All circuit devices located be ore the primary coil o the high-voltage trans ormer are said to be on the primary or low-voltage side o the x-ray circuit. T e timer, autotrans ormer, and (prereading) kilovoltage meter are all located in the low-voltage circuit. T e milliampere meter, however, is connected at the midpoint o the secondary coil o the high-voltage trans ormer. When studying a diagram o the x-ray circuit, it will be noted that the milliampere meter is grounded at the midpoint o the secondary coil (where it is at zero potential). T ere ore, it may be placed in the control panel sa ely. 54. (C) Radiographic results should be consistent and predictable with respect to positioning accuracy, exposure actors, and equipment operation. X-ray equipment should be tested and calibrated periodically as part o an ongoing quality assurance (QA)

283

program. T e ocal spot should be tested periodically to evaluate its size and its impact on recorded detail; this is accomplished using a slit camera, a pinhole camera, or a star pattern. o test the congruence o the light and x-ray elds, a radiopaque object such as a paper clip or a penny is placed at each corner o the light eld be ore the test exposure is made. Af er processing, the corners o the x-ray eld should be exactly delineated by the radiopaque objects. 55. (B) One generally thinks in terms o moving grids being totally superior to stationary grids because moving grids unction to blur the appearance o the lead strips on the radiographic image. Moving grids do, however, have several disadvantages. First, their complex mechanism is expensive and subject to mal unction. Second, today’s sophisticated x-ray equipment makes possible the use o extremely short exposures, a valuable eature whenever motion may be a problem (as in pediatric radiography). However, grid mechanisms requently are not able to oscillate rapidly enough or the short exposure times, and as a result, the grid motion can be “stopped,” and the lead strips then visible. T ird, patient dose is increased with moving grids. Since the central ray is not always centered to the grid because it is in motion, lateral decentering occurs (resulting in diminished receptor exposure), and consequently, an increase in exposure is needed to compensate (either manually or via AEC). 56. (C) PACS re ers to a picture archiving and communication system. Analog images (conventional images) can be digitized with a digitizer. PACS systems receive digital images and displays them on monitors or interpretation. T ese systems also store images and allow their retrieval at a later time. PACS systems provide us with a completely lmless radiology department. 57. (A) HVL may be used to express the quality o an x-ray beam. T e HVL o a particular beam is that thickness o an absorber that will decrease the intensity o the beam to one-hal its original value. I the original intensity o the beam was 78 R/min, the rst HVL will reduce the intensity to 39 R/min, the second HVL will reduce it to 19.5 R/min, and the third HVL will reduce it to 9.75 R/min, etc.

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58. (B) Quality Control re ers to our equipment and its sa e and accurate operation. Various components must be tested at speci ed intervals and test results must be within speci ed parameters. Any deviation rom those parameters must be corrected. Examples o equipment components that are tested annually are the ocal-spot size, linearity, reproducibility, ltration, kV, and exposure time. Kilovoltage settings can most e ectively be tested using an electronic kV meter; to meet required standards, the kV should be accurate to within + /–4 kV. Congruence is a term used to describe the relationship between the collimator light eld and the actual x-ray eld—they must be congruent (i.e., match) to within 2% o the SID. Collimators should be inspected and veri ed as accurate semiannually, that is, twice a year. Reproducibility testing should speci y that radiation output be consistent to within + /–5%. 59. (D) T e spinning-top test may be used to test timer accuracy in single-phase equipment. A spinning top is a metal disk with a small hole in its outer edge that is placed on a pedestal about 6 in high. An exposure is made (e.g., 0.1 s) while the top spins. Because a ull-wave-recti ed unit produces 120 x-ray photon impulses per second, in 0.1 s the IR should record 12 dots (i the timer is accurate). Because three-phase equipment produces almost constant potential rather than pulsed radiation, the standard spinning top cannot be used. An oscilloscope or synchronous spinning top must be employed to test the timers o three-phase equipment. 60. (C) Although the C x-ray tube is similar to direct-projection x-ray tubes, it has several special requirements. T e C x-ray tube must have a very high short-exposure rating and must be capable o tolerating several million heat units while still having a small ocal spot or optimal resolution. o help tolerate the very high production o heat units, the anode must be capable o high-speed rotation. T e x-ray tube produces a pulsed x-ray beam (1–5 ms) using up to about 1,000 mA. T e collimator assembly has two parts: T e prepatient, or predetector, collimator is at the x-ray tube and consists o multiple beam restrictions so that the x-ray beam diverges little. T is reduces patient dose and reduces the production o scattered radiation, thereby improving the C image. T e postpatient

collimator, or predetector collimator, con nes the exit photons be ore they reach the detector array and determines slice thickness. 61. (C) A spinning top is used to test the timer e ciency o single phase (1ϕ ) ull-wave-recti ed single-phase equipment. T e result should be a series o dots or dashes, with each dot representing a pulse o x-radiation. With 1ϕ ull-wave-recti ed current there should be 120 dots/pulses seen per second. One should visualize 12 dots/pulses at 1⁄10 sec, 6 dots at 0.05 sec, 10 dots at 1⁄12 sec, and 3 dots at 0.025 sec. I an incorrect number o dots/pulses is obtained, it is an indication o either timer mal unction/miscalibration or recti er ailure. Because 3ϕ equipment is at almost constant potential, a synchronous spinning top must be used or timer testing, and the result is a solid arc (rather than dots). T e number o degrees covered by the arc is measured and equated to a particular exposure time; one second exposure should demonstrate 360 degrees. 62. (B) X-ray tube li e may be extended by using exposure actors that produce a minimum o heat, that is, a lower milliampere-seconds and higher kilovoltage combination, whenever possible. When the rotor is activated, the lament current is increased to produce the required electron source (thermionic emission). Prolonged rotor time, then, can lead to shortened lament li e as a result o early vaporization. Large exposures to a cold anode will heat the anode sur ace, and the big temperature di erence can cause cracking o the anode. T is can be avoided by proper warming o the anode prior to use, thereby allowing su cient dispersion o heat through the anode. 63. (B) T e minimum response time, or minimum reaction time, is the length o the shortest exposure possible with a particular AEC. I less than the minimum response time is required or a particular exposure, the radiograph will exhibit excessive receptor exposure. T is problem becomes apparent when making exposures that require very short exposure times, such as when using high-milliamperage and/or ast imaging systems (e.g., ast lm–screen combinations in analog imaging). o resolve this problem, the radiographer should decrease the milliamperage rather than the kilovoltage in order to leave contrast una ected.

Answers: 58–70

64. (B) Given the milliamperage and exposure time, a radiographic rating chart enables the radiographer to determine the maximum sa e kilovoltage or a particular exposure. Because the heat load an anode will sa ely accept varies with the size o the ocal spot and the type o recti cation, these variables must be identi ed. Each x-ray tube has its own radiographic rating chart. T e speed o the imaging system has no impact on the use o a radiographic rating chart.

285

x-ray photons P rote ctive Al filtra tion Mirror Inca nde s ce nt light bulb Light Bulb illumina tion Congrue nt Light a nd X-ray be a ms Lowe rmos t s hutte rs Collima tor box

65. (D) DXA imaging is used to evaluate bone mineral density (BMD). It is the most widely used method o bone densitometry—it is low dose, precise, and uncomplicated to use/per orm. DXA uses two photon energies—one or sof tissue and one or bone. Since bone is denser and attenuates x-ray photons more readily, their attenuation is calculated to represent the degree o bone density. Bone densitometry/DXA can be used to evaluate bone mineral content o the body or part o it, to diagnosis osteoporosis, or to evaluate the e ectiveness o treatments or osteoporosis. 66. (A) Radiographic reproducibility is an important concept in producing high-quality diagnostic images. Radiographic results should be consistent and predictable not only in terms o positioning accuracy but also with respect to exposure actors. AEC devices (phototimers and ionization chambers) automatically terminate the x-ray exposure once a predetermined quantity o x-rays has penetrated the patient, thus ensuring consistent results. A penetrometer can be used to demonstrate e ects o kV on contrast. An induction motor has two parts, a stator and a rotor, and is used to rotate the anode. 67. (B) Some x-ray circuit devices, such as the transormer and autotrans ormer, will operate only on AC. T e e cient operation o the x-ray tube, however, requires the use o unidirectional current, so current must be recti ed be ore it gets to the x-ray tube. T e process o ull-wave recti cation changes the negative hal -cycle to a use ul positive hal cycle. An x-ray circuit recti cation system is located between the secondary coil o the high-voltage trans ormer and the x-ray tube. Recti ers are solid-state diodes made o semiconductive materials such as silicon, selenium, or germanium that conduct electricity in only one direction. T us, a series

Figure 5-14.

o recti ers placed between the trans ormer and x-ray tube unction to change AC to a more use ul unidirectional current. 68. (B) T e collimator assembly includes a series o lead shutters, a mirror, and a light bulb (Fig. 5-14). T e mirror and light bulb unction to project the size, location, and center o the irradiated eld. T e bulb’s emitted beam o light is de ected by a mirror placed at an angle o 45 degrees in the path o the light beam. In order or the projected light beam to be the same size as the x-ray beam, the ocal spot and the light bulb must be exactly the same distance rom the center o the mirror. 69. (B) T e input phosphor o an image intensi er receives remnant radiation emerging rom the patient and converts it to a uorescent light image. Directly adjacent to the input phosphor is the photocathode, which is made o a photoemissive alloy (usually, a cesium and antimony compound). T e uorescent light image strikes the photocathode and is converted to an electron image. T e electrons are care ully ocused to maintain image resolution by the electrostatic ocusing lenses through the accelerating anode and to the output phosphor or conversion back to light. 70. (A) T e x-ray photons emitted rom the anode ocus are heterogeneous in nature. T e low-energy photons must be removed because they are not penetrating enough to contribute to the image and because they do contribute to the patient’s skin

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dose. T e glass envelope and oil coolant provide approximately 0.5- to 1.0-mm Al equivalent ltration, which is re erred to as inherent because it is a built-in, permanent part o the tube head.

way in which they a ect the radiographic image. For optimal contrast, especially taking patient dose into consideration, higher kilovoltage and lower milliamperage are generally pre erred.

71. (C) Myelography requires that contrast medium be instilled into the lumbar subarachnoid space and distributed via gravity to various levels o the spinal canal. T is gravitational distribution is accomplished through the use o an x-ray table that is capable o angling or tilting during the procedure.

76. (B) In Bremsstrahlung (Brems) or “braking” x-ray production, a high-speed electron, accelerated toward a tungsten atom, is attracted (and “braked,” i.e., slowed down) by the positively charged nucleus and there ore is de ected rom its original course with a resulting loss o energy. T is energy loss is given up in the orm o an x-ray photon. T e electron might not give up all its kinetic energy in one such interaction; it might go on to have several more interactions deeper in the target, each time giving up an x-ray photon having less and less energy. T is is one reason the x-ray beam is heterogeneous (i.e., has a spectrum o energies). Brems radiation comprises 70% to 90% o the x-ray beam. T e other type o x-ray production that occurs in the tungsten anode is characteristic radiation. In this case, a high-speed electron encounters the tungsten atom and ejects a K-shell electron, leaving a vacancy in the K shell. An electron rom a shell above (e.g., the L shell) lls the vacancy and in doing so emits a K-characteristic ray. T e energy o the characteristic ray is equal to the di erence in energy between the K and L shells. K-characteristic x-rays rom a tungsten-target x-ray tube have 69 keV o energy. Characteristic radiation comprises very little o the x-ray beam (10–30%).

72. (A) T rough the action o thermionic emission, as the tungsten lament continually gives up electrons, it gradually becomes thinner with age. T is evaporated tungsten requently is deposited on the inner sur ace o the glass envelope at the tube window. When this happens, it acts as an additional lter o the x-ray beam, thereby reducing tube output. Also, the tungsten deposit actually may attract electrons rom the lament, creating a tube current, and causing puncture o the glass envelope. 73. (B) T e principle o sel -induction is an example o the second law o electromagnetics (Lenz’s law), which states that an induced current within a conductive coil will oppose the direction o the current that induced it. It is important to note that sel -induction is a characteristic o AC only. T e act that AC is constantly changing direction accounts or the opposing current set up in the coil. wo x-ray circuit devices operate on the principle o sel -induction. T e autotrans ormer operates on the principle o sel -induction and enables the radiographer to vary the kilovoltage. T e choke coil also operates on the principle o sel -induction; it is a type o variable resistor that may be used to regulate lament current. T e high-voltage trans ormer operates on the principle o mutual induction. 74. (B) Current is de ned as the amount o electric charge owing per second. Voltage is the potential di erence existing between two points. Resistance is the property o a circuit that opposes current ow. Capacitance describes a quantity o stored electricity. 75. (D) T e thicker and more dense the anatomic part being studied, the less bright will be the uoroscopic image. Both milliamperage and kilovoltage a ect the uoroscopic image in a way similar to the

77. (C) T at portion o the x-ray beam striking the IR and representing image anatomy is re erred to as the signal. Some o the initial x-ray beam is absorbed via photoelectric interaction; some is scattered via Compton scatter (creating noise). Signal-to-noise ratio (SNR) is an important actor in all o medical imaging. Noise impairs image resolution; a high SNR is desirable (more signal, less noise). Generally speaking, SNR increases as mAs increases— however, this is at the expense o patient dose. It is the responsibility o the radiographer to select technical actors and techniques that will provide a quality diagnostic image while keeping the ALARA concept in mind and minimizing patient dose. 78. (D) A computed tomographic (C ) imaging system has three component parts: a gantry, a computer, and an operator console. T e gantry component includes

Answers: 71–83

an x-ray tube, a detector array, a high-voltage generator, a collimator assembly, and a patient couch with its motorized mechanism. T e computer is exceedingly sophisticated, per orming thousands o calculations simultaneously per second. It is responsible or image reconstruction and postprocessing unctions. At the operator console, somewhat similar to a control panel used in projection radiography, are the controls or equipment operation and image manipulation. echnical actors are selected and monitored here, adjustments can be made, and the patient couch is operated rom here. 79. (D) T e rotating anode has a target (or ocal spot) on its beveled edge that orms the target angle. As the anode rotates, it constantly turns a new ace to the incoming electrons; this is the ocal track. T e portion o the ocal track that is bombarded by electrons is the actual ocal spot, and because o the target’s angle, the e ective or projected ocal spot is always smaller (line- ocus principle). T e anode heel e ect re ers to decreased beam intensity at the anode end o the x-ray beam. T e electrons impinging on the target have “boiled o ” the cathode lament as a result o thermionic emission. 80. (D) T e anode is made to rotate through the use o an induction motor. An induction motor has two main parts, a stator and a rotor. T e stator is the part located outside the glass envelope and consists o a series o electromagnets occupying positions around the stem o the anode. T e stator’s electromagnets are supplied with current, and the associated magnetic elds unction to exert a drag or pull on the rotor within the glass envelope. T e anode is a 2- to 5-in diameter molybdenum or graphite disk with a beveled edge. T e beveled sur ace has a ocal track o tungsten and rhenium alloy. T e anode rotates at about 3,600 rpm (high-speed anode rotation is about 10,000 rpm) so that heat generated during x-ray production is evenly distributed over the entire track. Rotating anodes can withstand delivery o a greater amount o heat or a longer period o time than stationary anodes. 81. (D) T e AEC automatically adjusts the exposure required or body parts that have di erent thicknesses and densities. Proper unctioning o the phototimer depends on accurate positioning by the radiographer. T e correct photocell(s) must be selected, and the anatomic part o interest must

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completely cover the photocell to achieve the desired receptor exposure. I collimation is inadequate and a eld size larger than the part is used, excessive scattered radiation rom the body or tabletop can cause the AEC to terminate the exposure prematurely, resulting in an underexposed radiograph. Backup time should always be selected on the manual timer to prevent patient overexposure and to protect the x-ray tube rom excessive heat production, should the AEC malunction. Selection o the optimal kilovoltage or the part being radiographed is essential—no practical amount o milliampere-seconds can make up or inadequate penetration (kilovoltage), and excessive kilovoltage can cause the AEC to terminate the exposure prematurely. A technique chart, there ore, is strongly recommended or use with AEC; it should indicate the optimal kilovoltage or the part, the photocells that should be selected, and the backup time that should be set. 82. (C) T e anode is made to rotate through the use o an induction motor. An induction motor has two main parts, a stator and a rotor. T e stator is the part located outside the glass envelope and consists o a series o electromagnets occupying positions around the stem o the anode. T e stator’s electromagnets are supplied with current and the associated magnetic elds unction to exert a drag or pull on the rotor within the glass envelope. T e anode is a 2- to 5-in diameter molybdenum or graphite disc with a beveled edge. T e beveled sur ace has a ocal track o tungsten and rhenium alloy. T e anode rotates at about 3,600 rpm (high-speed anode rotation is about 10,000 rpm), so that heat generated during x-ray production is evenly distributed over the entire track. Rotating anodes can withstand delivery o a greater amount o heat or a longer period o time than stationary anodes. 83. (D) Moving the image intensi er closer to the patient during uoroscopy reduces the distance between the x-ray tube (source) and the image intensi er (IR), that is, the SID. It ollows that the distance between the part being imaged (object) and the image intensier (IR), that is, the object-to-image distance (OID), is also reduced. T e shorter OID produces less magni cation and better image quality. As the SID is reduced, the intensity o the x-ray photons at the image intensi er’s input phosphor increases, stimulating the automatic brightness control (ABC) to

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II II OID

S ID OID

S ID

Obje ct

Obje ct

Figure 5-15.

decrease the milliamperage and thereby decreasing patient dose (Fig. 5-15). 84. (B) X-ray tube ocal spots/targets are constructed according to the line- ocus principle—the ocal spot is angled (usually, 12–17 degrees) to the vertical. As the actual ocal spot is projected downward, it is oreshortened; thus, the e ective ocal spot is always smaller than the actual ocal spot. As it is projected toward the cathode end o the x-ray beam, the e ective ocal spot becomes larger and approaches its actual size. As it is projected toward the anode end, and oreshortening becomes more pronounced, the e ective ocal spot becomes smaller. Anode heel e ect re ers to the variation in x-ray beam intensity between the anode and cathode. Because o the anode angle, x-ray beam intensity is greater at the cathode end o the beam and less at the anode into the beam–as the x-ray beam attempts to diverge, it is absorbed by the “heel” o the anode at that end o the x-ray tube. 85. (D) X-ray tube targets are constructed according to the line- ocus principle—the ocal spot is angled (usually, 12–17 degrees) to the vertical. As the actual ocal spot is projected downward, it is oreshortened; thus, the e ective ocal spot is always smaller than the actual ocal spot. As it is projected toward the cathode end o the x-ray beam, the e ective ocal spot becomes larger and approaches its actual size. As it is projected toward the anode end, and oreshortening becomes more pronounced, the e ective ocal spot becomes smaller.

86. (C) T e brightness gain o image intensi ers is 5,000 to 20,000. T is increase is accounted or in two ways. As the electron image is ocused to the output phosphor, it is accelerated by high voltage (about 25 kV). T e output phosphor is only a raction o the size o the input phosphor, and this decrease in image size represents brightness gain, termed mini cation gain. T e ratio o the number o x-ray photons at the input phosphor compared to the number light photons at the output phosphor is termed ux gain. otal brightness gain is equal to the product o mini cation gain and ux gain. 87. (D) T e input phosphor o image intensi ers is usually made o cesium iodide. For each x-ray photon absorbed by cesium iodide, approximately 5,000 light photons are emitted. As the light photons strike a photoemissive photocathode, a number o electrons are released rom the photocathode and ocused toward the output side o the image tube by voltage applied to the negatively charged electrostatic ocusing lenses. T e electrons are then accelerated through the neck o the tube, where they strike the small (0.5–1 in) output phosphor that is mounted on a at glass support. T e entire assembly is enclosed within a 2- to 4-mm thick vacuum glass envelope. Remember that the image on the output phosphor is mini ed, brighter, and inverted (electron ocusing causes image inversion). Input screen diameters o 5 to 12 in are available. Although smaller-diameter input screens improve resolution, they do not permit a large FOV, that is, viewing o large patient areas. Dual- and triple- eld image intensi ers are available that permit magni ed viewing o uoroscopic images. o achieve magni cation, the voltage to the ocusing lenses is increased and a smaller portion o the input phosphor is used, thereby resulting in a smaller FOV. Because mini cation gain is now decreased, the image is not as bright. T e mA is automatically increased to compensate or the loss in brightness when the image intensier is switched to magni cation mode. Entrance skin exposure (ESE) can increase dramatically as the FOV decreases (i.e., as magni cation increases). As FOV decreases, magni cation o the output screen image increases, there is less noise because increased mA provides a greater number o x-ray photons, and contrast and resolution improve. T e ocal point in the magni cation mode is urther

Answers: 84–95

away rom the output phosphor (as a result o increased voltage applied to the ocusing lenses) and there ore the output image is magni ed. 88. (B) T ere are two main types o mobile x-ray equipment—capacitor-discharge and batterypowered. Although capacitor-discharge units are light, and there ore airly easy to maneuver, the battery-powered mobile unit is very heavy (largely because it carries its heavy-duty power source). It is, however, capable o storing a large milliampere-seconds capacity or extended periods o time. T ese units requently have a capacity o 10,000 mAs, with 12 hours required or a ull charge. 89. (C) Most image-intensi er tubes are either dualeld or tri eld, indicating the diameter o the input phosphor. When a change to a smaller-diameter mode is made, the voltage on the electrostatic ocusing lenses is increased, and the result is a magni ed but dimmer image. T e milliamperage will be increased automatically to compensate or the loss in brightness with a magni ed image, resulting in higher patient dose in the smaller-diameter modes. 90. (B) O - ocus, or extra ocal, radiation is produced as electrons strike metal sur aces other than the ocal track and produce x-rays that emerge with the primary beam at a variety o angles. T is radiation is responsible or indistinct images outside the collimated eld. Mounting a pair o shutters as close to the source as possible minimizes o - ocus radiation. 91. (A) All circuit devices located be ore the primary coil o the high-voltage trans ormer are said to be on the primary or low-voltage side o the x-ray circuit. T e timer, autotrans ormer, and (prereading) kilovoltage meter are all located in the low-voltage circuit. T e secondary/high-voltage side o the circuit begins with the secondary coil o the high-voltage trans ormer. T e mA meter is connected at the midpoint o the secondary coil o the high-voltage trans ormer. Following the secondary coil is 4 the recti cation system, and the x-ray tube. rans ormers are used to change the value o alternating current (AC). T ey operate on the principle o mutual induction. T e secondary coil o the step-up trans ormer is located in the high-voltage

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(secondary) side o the x-ray circuit. T e step-down trans ormer, or lament trans ormer, is located in the lament circuit and serves to regulate the voltage and current provided to heat the x-ray tube lament. T e recti cation system is also located on the high-voltage, or secondary, side o the x-ray circuit. 92. (C) A phototimer is one type o AEC that actually measures light. As x-ray photons penetrate and emerge rom a part, a uorescent screen beneath the IR glows, and the uorescent light charges a photomultiplier tube. Once a predetermined charge has been reached, the exposure terminates automatically. A parallel-plate ionization chamber is another type o AEC. A radiolucent chamber is located beneath the patient (between the patient and the IR). As photons emerge rom the patient, they enter the chamber and ionize the air within it. Once a predetermined charge has been reached, the exposure is terminated automatically. Motion o magnetic elds inducing current in a conductor re ers to the principle o mutual induction. 93. (B) T e x-ray tube lament is made o thoriated tungsten. When heated to incandescence (white hot), the lament liberates electrons—a process called thermionic emission. It is these electrons that will become the tube current (mA). As heat is increased, more electrons are released, and milliamperage increases. 94. (D) Single-phase radiographic equipment is less e cient than three-phase equipment because it has a 100% voltage ripple. With three-phase equipment, voltage never drops to zero, and x-ray intensity is signi cantly greater. o produce similar receptor exposure, only two-thirds o the original milliampere-seconds would be used or three-phase, six-pulse equipment. With three-phase, 12-pulse equipment, the original milliampere-seconds would be cut in hal (one-hal o 15 mAs = 7.5). 95. (A) Magni cation radiography may be used to demonstrate small, delicate structures that are di cult to image with conventional radiography. Because OID is an integral part o magni cation radiography, the problem o magni cation unsharpness arises. T e use o a ractional ocal spot (0.3 mm or smaller) is essential to the maintenance o image sharpness in magni cation images. Radiographic rating charts should be consulted because the heat

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load to the anode may be critical in magni cation radiography. T e long exposures typical o imageintensi ed uoroscopy and tomography make the use o a ractional ocal spot generally impractical and hazardous to the anode. 96. (C) A radiographic rating chart enables the radiographer to determine the maximum sa e milliamperage, exposure time, and kilovoltage or a given exposure using a particular x-ray tube. Because the heat load that an anode will sa ely accept varies with the size o the ocal spot, type o recti cation, and anode rotation, these variables must also be identi ed. Each x-ray tube has its own characteristics and its own rating chart. First, nd the chart with the identi ying single-phase sine wave in the upper right corner and the correct ocal-spot size in the upper lef corner (chart C). Once the correct chart has been identi ed, locate 0.02 s on the horizontal axis, and ollow its line up to where it intersects with the 400-mA curve. T en, draw a line to where this point meets the vertical (kV) axis; it intersects at exactly 80 kV. T is is the maximum permissible kilovoltage exposure at the given milliampere-seconds or this x-ray tube. T e radiographer should always use somewhat less than the maximum exposure. 97. (B) A radiographic rating chart enables the radiographer to determine the maximum sa e milliamperage, exposure time, and kilovoltage or a given exposure using a particular x-ray tube. Because the heat load that an anode will accept sa ely varies with the size o the ocal spot, type o recti cation, and anode rotation, these variables must also be identied. Each x-ray tube has its own characteristics and its own rating chart. Only x-ray tubes A and B, the three-phase recti ed x-ray tubes, will sa ely permit this exposure. Locate 0.1 s on the horizontal axis and ollow it up to where it intersects with the 400-mA curve. X-ray tube A will permit over 150 kV sa ely, whereas x-ray tube B will permit only about 92 kV sa ely. Notice the signi cant di erence between the two, which is solely due to the di erence in ocalspot size. X-ray tube C will permit only about 75 kV at the given mAs. 98. (A) A radiographic rating chart enables the radiographer to determine the maximum sa e milliamperage, exposure time, and kilovoltage or a given exposure using a particular x-ray tube. Because the

heat load that an anode will sa ely accept varies with the size o the ocal spot, type o recti cation, and anode rotation, these variables must also be identi ed. Each x-ray tube has its own characteristics and its own rating chart. Find the correct chart or the three-phase, 1.0-mm ocal-spot x-ray tube. Locate 0.1 s on the horizontal (seconds) axis and ollow it up to where it intersects with the 120-kV line on the vertical (kV) axis. T ey intersect just below the 300-mA curve, at approximately 310 mA. T us, 300 mA is the maximum sa e milliamperage or this particular group o exposure actors and x-ray tube. 99. (B) Each x-ray exposure made by the radiographer produces hundreds or thousands o heat units at the target. I the examination requires several consecutive exposures, the potential or extreme heat load is increased. Just as each x-ray tube has its own radiographic rating chart, each tube also has its own anode cooling curve to describe its unique heating and cooling characteristics. An x-ray tube generally cools most rapidly during the rst 2 minutes o nonuse. First, note that the tube is saturated with heat at 300,000 HU. In order or another 160,000 HU to be sa ely applied, the x-ray tube must rst release 160,000 HU, which means that it has to cool down at least to 140,000 HU. Find the 140,000 HU point on the vertical axis and ollow across to where it intersects with the cooling curve. It intersects at about the 4-minute point. 100. (B) When a spinning top is used to test the e ciency o a single-phase timer, the result is a series o dots or dashes, with each representing a pulse o radiation. With ull-wave-recti ed current and a possible 120 dots (pulses) available per second, one should visualize 12 dots at 1/10 s, 24 dots at 1/5 s, 6 dots at 1/20 s, and so on. However, because three-phase equipment is at almost constant potential, a synchronous spinning top must be used, and the result is a solid arc (rather than dots). T e number o degrees ormed by the arc is measured and equated to a particular exposure time. A multitude o small, mesh-like squares describes a screen contact test. An aluminum step wedge (penetrometer) may be used to demonstrate the e ect o kilovoltage on contrast (demonstrating a series o gray tones rom white to black), with a greater number o grays demonstrated at higher kilovoltage levels.

Answers: 96–107

101. (D) As the anode angle is decreased (made steeper), a larger actual ocal spot may be used while still maintaining the same small e ective ocal spot. Because the actual ocal spot is larger, it can accommodate a greater heat load. However, with steeper (smaller) anode angles, the anode heel e ect is accentuated and can compromise IR coverage. 102. (B) T e minimum response time, or minimum reaction time, is the length o the shortest exposure possible with a particular AEC. I less than the minimum response time is required or a particular exposure, the radiograph will exhibit excessive receptor exposure. T e problem may become apparent when using ast imaging systems (e.g., high milliamperage or ast lm–screen combinations in analog imaging) or when imaging small or easily penetrated body parts. T e backup timer unctions to protect the patient rom overexposure and the x-ray tube rom overload. 103. (C) NCRP Report No. 102 states that the exposure switch on mobile radiographic units shall be so arranged that the operator can stand at least 2 m (6 f ) rom the patient, the x-ray tube, and the use ul beam. An appropriately long exposure cord accomplishes this requirement. T e uoroscopic and/or radiographic exposure switch or switches must be o the “dead man” type; that is, the exposure will terminate should the switch be released. A lead apron should be carried with every mobile x-ray unit or the operator to wear during the exposure. Finally, the radiographer must be certain to alert individuals in the area, enabling unnecessary occupants to move away, be ore making the exposure. 104. (B) In Compton scatter, a high-energy (high kilovoltage) x-ray photon ejects an outer-shell electron in tissue or other absorber. T e ejected electron is called a recoil electron. Although the x-ray photon is de ected with somewhat reduced energy (modied scatter), it retains most o its original energy and exits the body as an energetic scattered photon. Because the scattered photon exits the body, it does not pose a radiation hazard to the patient. It can, however, contribute to image og and pose a radiation hazard to personnel (as in uoroscopic procedures). In the photoelectric e ect, a relatively low-energy (low kilovoltage) x-ray photon uses all its energy (true/total absorption) to eject an

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inner-shell electron, leaving an orbital vacancy. An electron rom the shell above drops down to ll the vacancy and in doing so gives up energy in the orm o a characteristic ray. T e photoelectric e ect is more likely to occur in absorbers having high atomic number (e.g., bone or positive contrast media) and contributes signi cantly to patient dose because all the photon energy is absorbed by the patient (and, there ore, is responsible or the production o short-scale contrast). Brems and characteristic x-rays are produced at the ocal spot as high-speed electrons are rapidly decelerated. 105. (C) Each time an x-ray exposure is made, heat is produced in the x-ray tube. O all the energy used to make an exposure, 99.8% is converted to heat, and only 0.2% is converted to x-ray photon energy. Since greater heat production leads to increased wear and tear on the x-ray tube, decreasing its useul li e, the radiographer should be able to calculate heat units and to understand the means o keeping heat production to a minimum. Heat units (HU) or a single-phase x-ray unit are determined by using the ormula HU = mA × kV × time. Heat units or three-phase and high- requency x-ray equipment are determined by using the ormula HU = mA × kV × time × 1.4. High milliampere-seconds technical actors produce ar more heat units than low milliampere-seconds technical actors. 106. (D) With single-phase, ull-wave-recti ed equipment, the voltage is constantly changing rom 0% to 100% o its maximum value. It drops to 0 every 180 degrees (o the AC wave orm); that is, there is 100% voltage ripple. With three-phase equipment, the voltage ripple is signi cantly smaller. T reephase, six-pulse equipment has a 13% voltage ripple, and three-phase, 12-pulse equipment has a 3.5% ripple. T ere ore, the voltage never alls below 87% to 96.5% o its maximum value with threephase equipment, and it closely approaches constant potential (direct current [DC]). 107. (A) T e spinning-top test is used to test timer accuracy or recti er operation. Because singlephase, ull-wave-recti ed current has 120 use ul impulses per second, a 1-s exposure o the spinning top should demonstrate 120 dots. T ere ore, a 0.05-s exposure should demonstrate six dots. Anything more or less than this indicates that the time

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station needs calibration. I exactly one-hal the expected number o dots appears, recti er ailure is suspected. 108. (B) T e smaller the ocal spot, the more limited the anode is with respect to the quantity o heat it can sa ely accept. As the target angle decreases, the actual ocal spot can be increased while still maintaining a small e ective ocal spot. T ere ore, group (B) o ers the greatest heat-loading potential, with a steep target angle and a large actual ocal spot. It must be remembered, however, that a steep target angle increases the heel e ect, and IR coverage may be compromised. 109. (C) T e IP is used to house, support, and protect the PSP. T e IP ront should be made o a sturdy material with a low atomic number because attenuation o the remnant beam is undesirable. Bakelite (the orerunner o today’s plastics) and magnesium (the lightest structural metal) are the materials used most commonly or cassette ronts. T e high atomic number o tungsten makes it inappropriate as an IP ront material. 110. (A) Quality Control re ers to our equipment and its sa e and accurate operation. Various components must be tested at speci ed intervals and test results must be within speci ed parameters. Any deviation rom those parameters must be corrected. Examples o equipment components that are tested annually are the ocal-spot size, linearity, reproducibility, ltration, kV, and exposure time. Kilovoltage settings can most e ectively be tested using an electronic kV meter; to meet required standards, the kV should be accurate to within + /–4 kV. Congruence is a term used to describe the relationship between the collimator light eld and the actual x-ray eld— they must be congruent (i.e., match) to within 2% o the SID. Collimators should be inspected and veri ed as accurate semiannually. Reproducibility testing should speci y that radiation output be consistent to within + /–5%. 111. (B) T e gure illustrates the component parts o a rotating-anode x-ray tube enclosed within a glass envelope (Number 3) to preserve the vacuum necessary or x-ray production. Number 4 is the rotating anode with its beveled ocal track at the periphery (Number 8) and its stem (at Number 5). Numbers 6 and 7 are the stator and rotor,

respectively—the two components o an induction motor—whose unction is to rotate the anode. Number 1 is the lament o the cathode assembly, which is made o thoriated tungsten and unctions to liberate electrons (thermionic emission) when heated to white hot (incandescence). Number 2 is the nickel ocusing cup, which unctions to direct the liberated lament electrons to the ocal spot. 112. (B) T e image intensi er’s input phosphor receives the remnant radiation emerging rom the patient and converts it into a uorescent light image. Very close to the input phosphor, separated by a thin, transparent layer, is the photocathode. T e photocathode is made o a photoemissive alloy, usually an antimony and cesium compound. T e uorescent light image strikes the photocathode and is converted to an electron image that is ocused by the electrostatic lenses to the output phosphor. 113. (C) T e AEC automatically terminates the exposure when the proper receptor exposure has been reached. T e important advantage o the phototimer, then, is that it can accurately duplicate receptor exposures. It is very use ul in providing accurate comparison in ollow-up examinations and in decreasing patient exposure dose by reducing the number o “retakes” needed because o improper exposure. T e AEC automatically adjusts the exposure required or body parts with di erent thicknesses and densities. However, proper unctioning o the phototimer depends on accurate positioning by the radiographer. T e correct photocell(s) must be selected, and the anatomic part o interest must completely cover the photocell to achieve the desired receptor exposure. I collimation is inadequate and a eld size larger than the part is used, excessive scattered radiation rom the body or tabletop can cause the AEC to terminate the exposure prematurely, resulting in an underexposed image. 114. (A) T e image intensi er’s input phosphor receives the remnant beam rom the patient and converts it to a uorescent light image. o maintain resolution, the input phosphor is made o cesium iodide crystals. Cesium iodide is much more e cient in this conversion process than was the phosphor used previously, zinc cadmium sul de. Calcium tungstate was the phosphor used in cassette intensi ying screens or many years prior to the development o rare earth phosphors such as gadolinium oxysul de.

Answers: 108–120

115. (D) T e greater the number o electrons making up the electron stream and bombarding the target, the greater is the number o x-ray photons produced. Although kilovoltage usually is associated with the energy o the x-ray photons, because a greater number o more energetic electrons will produce more x-ray photons, an increase in kilovoltage also will increase the number o photons produced. Speci cally, the quantity o radiation produced increases as the square o the kilovoltage. T e material composition o the tube target also plays an important role in the number o x-ray photons produced. T e higher the atomic number o this material, the denser and more closely packed are the atoms making up the material, and there ore, the greater is the chance o an interaction between a high-speed electron and the target material. 116. (A) A photostimulable (light-stimulated) phosphor, or simply PSP, is used in CR. CR does not use intensi ying screens or lm. Rather, the CR cassette contains a photostimulable phosphor that unctions as the IR. Upon exposure, the PSP stores in ormation. T e IP is placed into a special scanner/processor where the PSP is scanned with a laser light and the stored image is displayed on the computer monitor. 117. (D) Although the C x-ray tube is similar to direct-projection x-ray tubes, it has several special requirements. T e C x-ray tube must have a very high short-exposure rating and must be capable o tolerating several million heat units while still having a small ocal spot or optimal resolution. o help tolerate the very high production o heat units, the anode must be capable o high-speed rotation. T e x-ray tube produces a pulsed x-ray beam (1–5 ms) using up to about 1,000 mA.

293

118. (C) T e lead strips o a ocused grid are angled to correspond to the con guration o the divergent x-ray beam. T us, any radiation that is changing direction, as is typical o scattered radiation, will be trapped by the lead oil strips. However, i the central ray and the grid center do not correspond, the lead strips will absorb the use ul radiation. T e absorption o primary radiation is termed cuto and results in diminished receptor exposure. 119. (D) A synchronous spinning-top test is used to test timer accuracy or recti er unction in threephase equipment. Because three-phase, ullwave- recti ed current would expose a 360-degree arc each second, a 60-ms (0.06-s) exposure should expose a 21.6-degree arc (360 degrees × 0.06 = 21.6 degrees). Anything more or less indicates timer inaccuracy. I exactly one-hal the expected arc appears, recti er ailure should be suspected. 120. (A) T at portion o the x-ray beam striking the IR and representing image anatomy is re erred to as the signal. Some o the initial x-ray beam is absorbed via photoelectric interaction; some is scattered via Compton scatter (creating noise). Signal-to-noise ratio (SNR) is an important actor in all o medical imaging. Noise impairs image resolution; a high SNR is desirable (more signal, less noise). Noise impairs contrast resolution. Generally speaking, SNR increases as mAs increases—however, this is at the expense o patient dose. It is the responsibility o the radiographer to select technical actors and techniques that will provide a quality diagnostic image while keeping the ALARA concept in mind and minimizing patient dose.

Subspecialty List

QUESTION NUMBER AND SUBSPECIALTY correspond to subcategories in each o the f ve ARRT examination specif cation sections 1. Quality control o imaging equipment and accessories 2. Principles o radiation physics 3. Imaging equipment 4. Imaging equipment 5. Imaging equipment 6. Principles o radiation physics 7. Imaging equipment 8. Principles o radiation physics 9. Imaging equipment 10. Imaging equipment 11. Principles o radiation physics 12. Imaging equipment 13. Imaging equipment 14. Imaging equipment 15. Principles o radiation physics 16. Imaging equipment 17. Imaging equipment 18. Imaging equipment 19. Quality control o imaging equipment and accessories 20. Principles o radiation physics 21. Principles o radiation physics 22. Imaging equipment 23. Imaging equipment 24. Quality control o imaging equipment and accessories 25. Quality control o imaging equipment and accessories 26. Imaging equipment 27. Imaging equipment 28. Quality control o imaging equipment and accessories 29. Imaging equipment

294

30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64.

Quality control o imaging equipment and accessories Quality control o imaging equipment and accessories Imaging equipment Principles o radiation physics Imaging equipment Imaging equipment Imaging equipment Principles o radiation physics Imaging equipment Imaging equipment Imaging equipment Imaging equipment Quality control o imaging equipment and accessories Imaging equipment Imaging equipment Imaging equipment Imaging equipment Imaging equipment Principles o radiation physics Imaging equipment Quality control o imaging equipment and accessories Imaging equipment Principles o radiation physics Imaging equipment Quality control o imaging equipment and accessories Imaging equipment Imaging equipment Principles o radiation physics Quality control o imaging equipment and accessories Quality control o imaging equipment and accessories Imaging equipment Quality control o imaging equipment and accessories Quality control o imaging equipment and accessories Imaging equipment Imaging equipment

Subspecialty List

65. 66. 67. 68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 78. 79. 80. 81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92.

Imaging equipment Quality control o imaging equipment and accessories Imaging equipment Quality control o imaging equipment and accessories Imaging equipment Imaging equipment Imaging equipment Quality control o imaging equipment and accessories Imaging equipment Principles o radiation physics Imaging equipment Principles o radiation physics Principles o radiation physics Imaging equipment Imaging equipment Imaging equipment Quality control o imaging equipment and accessories Imaging equipment Imaging equipment Principles o radiation physics Quality control o imaging equipment and accessories Imaging equipment Imaging equipment Imaging equipment Imaging equipment Quality control o imaging equipment and accessories Imaging equipment Imaging equipment

Targeted Reading Bushong SC. Radiologic Science or echnologists. 10th ed. St. Louis, MO: Mosby; 2013. Selman J. T e Fundamentals o Imaging Physics and Radiobiology. 9th ed. Spring eld, IL: Charles C. T omas; 2000. Carlton RR, Adler AM. Principles o Radiographic Imaging. 5th ed. Albany, NY: Delmar; 2013. Shephard C . Radiographic Image Production and Manipulation. 1st ed. New York, NY: McGraw-Hill; 2003. Saia DA. Radiography PREP. 8th ed. New York, NY: McGraw-Hill; 2015. NCRP Report No. 102 Medical x-ray, Electron Beam and Gamma-Ray Protection or Energies up to 50 MeV

93. 94. 95. 96. 97. 98. 99. 100. 101. 102. 103. 104. 105. 106. 107. 108. 109. 110. 111. 112. 113. 114. 115. 116. 117. 118. 119. 120.

295

Imaging equipment Imaging equipment Imaging equipment Quality control o imaging equipment and accessories Quality control o imaging equipment and accessories Quality control o imaging equipment and accessories Quality control o imaging equipment and accessories Quality control o imaging equipment and accessories Imaging equipment Imaging equipment Imaging equipment Principles o radiation physics Imaging equipment Principles o radiation physics Quality control o imaging equipment and accessories Imaging equipment Imaging equipment Quality control o imaging equipment and accessories Imaging equipment Imaging equipment Imaging equipment Imaging equipment Principles o radiation physics Imaging equipment Imaging equipment Quality control o imaging equipment and accessories Quality control o imaging equipment and accessories Quality control o imaging equipment and accessories

(Equipment Design, Per ormance and Use) NCRP, 1989. NCRP Report No 99. Quality Assurance or Diagnostic Imaging. NCRP, 1990. Fosbinder R, Orth D. Essentials o Radiologic Science. Baltimore, MD: Lippincott Williams & Wilkins; 2012. Fosbinder RA, Kelsey CA. Essentials o Radiologic Science. 1st ed. New York, NY: McGraw-Hill; 2002. Bontrager KL, Lampignano JP. extbook o Radiographic Positioning and Related Anatomy. 8th ed. St Louis, MO: Mosby; 2014. Frank ED, Long BW, Smith BJ. Merrill’s Atlas o Radiographic Positioning and Procedures, Vols 1, 2, and 3. 12th ed. St. Louis, MO: Mosby; 2012.

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CHAPTER 6

Practice Test 1 Questions

DIRECTIONS (Questions 1 through 200): Each of the numbered items or incomplete statements in this section is followed by answers or by completions of the statement. Select the one lettered answer or completion that is best in each case. 1. Europium-activated barium uorohalide is associated with (A) rare earth intensi ying screens (B) image intensi ers (C) PSP storage plates (D) lament material 2. T e threat o bodily harm, with apparent ability to do so, is termed (A) (B) (C) (D)

assault battery alse imprisonment invasion o privacy

3. T e position seen in Figure 6-1 is used to demonstrate (A) (B) (C) (D)

AP elbow, partial exion, distal humerus AP elbow, partial exion, proximal orearm lateral elbow, partial exion, distal humerus lateral elbow, partial exion, proximal orearm

Figure 6-1. Reproduced with permission rom Peart O. Lange Radiographic Positioning Flashcards. New York, NY: McGraw-Hill; 2014.

4. An acute reaction caused by ingestion or injection o a sensitizing agent describes (A) (B) (C) (D)

asthma anaphylaxis myocardial in arction rhinitis

5. As the CR laser scanner/reader recognizes the phosphostimulated luminescence (PSL) released by the PSP storage plate, it constructs a graphic representation o pixel value distribution called a (A) (B) (C) (D)

processing algorithm histogram lookup table exposure index

297

298

6: Practice Test 1

6. An accurately positioned oblique position o the rst through ourth lumbar vertebrae will demonstrate the classic “Scotty dog.” What bony structure does the Scotty dog’s neck represent? (A) Superior articular process (B) Pedicle (C) ransverse process (D) Pars interarticularis

1 2

3

14

7. How is source-to-image distance (SID) related to exposure rate and receptor exposure? 13

(A) As SID increases, exposure rate increases and receptor exposure increases. (B) As SID increases, exposure rate increases and receptor exposure decreases. (C) As SID increases, exposure rate decreases and receptor exposure increases. (D) As SID increases, exposure rate decreases and receptor exposure decreases. 8. What in ormation must be included on an x-ray image or it to be considered as legitimate legal evidence?

4

12 11

10 9

8

7

10. T e principal late e ects o ionizing radiation on humans include 1. local tissue damage 2. genetic e ects 3. malignant disease

(A) (B) (C) (D)

(A) (B) (C) (D)

9. Figure 6-2 illustrates a sectional image o the abdomen. Which o the ollowing is represented by the number 4? (A) (B) (C) (D)

Le colic exure Pancreas Le kidney Spleen

5

Figure 6-2. Courtesy o Stam ord Hospital, Department o Radiology.

1. Name o acility where examination per ormed 2. Examination date 3. Date o birth 1 only 1 and 2 only 2 and 3 only 1, 2, and 3

6

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

11. Which o the ollowing procedures requires that contrast medium be injected into the ureters? (A) (B) (C) (D)

Cystogram Urethrogram Retrograde pyelogram Cystourethrogram

12. What is the Standard International unit o radiation exposure? (A) (B) (C) (D)

R rad Gya Gyt

Questions: 6–20

13. Which o the ollowing combinations would pose the least hazard to a particular anode? (A) (B) (C) (D)

0.6-mm 0.6-mm 1.2-mm 1.2-mm

ocal spot, 75 kVp, 30 mAs ocal spot, 85 kVp, 15 mAs ocal spot, 75 kVp, 30 mAs ocal spot, 85 kVp, 15 mAs

14. What is the structure indicated by the letter I in Figure 6-3? (A) (B) (C) (D)

Greater tubercle Coronoid process Coracoid process Acromion process

299

16. T e CR should be directed to the center o the part o greatest interest in order to avoid (A) (B) (C) (D)

rotation distortion magni cation oreshortening elongation

17. Federal regulations regarding in ection control in the workplace, as amended by the Occupational Sa ety and Health Administration (OSHA), make which o the ollowing requirements? 1. Hepatitis B immunizations must be made available to all hospital employees. 2. Puncture-proo containers must be provided or all used needles. 3. Follow-up care must be provided to any sta accidentally exposed to blood splash/needle stick. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

18. Imper ect expansion o the lung(s), o en accompanied by dyspnea, is called (A) (B) (C) (D)

COPD pneumonia pneumothorax atelectasis

19. Which o the ollowing radiologic examinations requires preparation consisting o a low-residue diet, cathartics, and enemas?

Figure 6-3. Courtesy o Bob Wong, RT.

15. Which o the ollowing indicates the scapular notch seen in Figure 6-3? (A) (B) (C) (D)

D H K M

(A) (B) (C) (D)

Upper GI series Small bowel series Barium enema (BE) Intravenous (IV) cystogram

20. T e exposure timer settings on three-phase radiographic equipment must be tested annually and must be accurate to within (A) (B) (C) (D)

+ /–2% + /–5% + /–10% + /–20%

300

6: Practice Test 1

21. Fluoroscopic equipment eatures designed to eliminate unnecessary radiation exposure to patients and/or personnel include 1. protective curtain 2. ltration 3. collimation (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

22. Which o the ollowing will best demonstrate the lumbosacral articulation in the AP position? (A) (B) (C) (D)

CR perpendicular to L3 CR perpendicular to L5 to S1 CR caudad 30 to 35 degrees CR cephalad 30 to 35 degrees

23. T e ollowing projection(s) require(s) that the shoulder be placed in external rotation? 1. AP humerus 2. Lateral orearm 3. Lateral humerus (A) (B) (C) (D)

26. Which o the ollowing is most likely to produce a high-quality image? (A) (B) (C) (D)

Small image matrix High signal-to-noise ratio (SNR) Large pixel size Low resolution

27. A decrease rom 90 to 77 kVp in SF/analog imaging will result in a decrease in which o the ollowing? 1. Wavelength 2. Scale o grays 3. Optical density (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

28. T e image shown in Figure 6-4 was made in the ollowing recumbent position (A) (B) (C) (D)

RAO Lateral LPO PA

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

24. During endoscopic retrograde cholangiopancreatography (ERCP) examination, contrast medium is injected into the (A) (B) (C) (D)

hepatic duct cystic duct pancreatic duct common bile duct

25. Which o the ollowing is (are) well demonstrated in the oblique position o the cervical vertebrae? 1. Pedicles 2. Disk spaces 3. Apophyseal joints (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

Figure 6-4. Courtesy o Stam ord Hospital, Department o Radiology.

Questions: 21–37

29.

erms that re er to size distortion include 1. magni cation 2. attenuation 3. elongation (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

30. Advantages o high- requency generators include 1. small size 2. decreased patient dose 3. nearly constant potential (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

31. Biologic material is most sensitive to radiation exposure under which o the ollowing conditions? (A) (B) (C) (D)

Deoxygenated Oxygenated Hypoxic Anoxic

32. Which o the ollowing is the pre erred scheduling sequence? (A) Lower GI series, abdomen ultrasound, upper GI series. (B) Abdomen ultrasound, lower GI series, upper GI series. (C) Abdomen ultrasound, upper GI series, lower GI series. (D) Upper GI series, lower GI series, abdomen ultrasound. 33. T e RAO position is used to project the sternum to the le o the thoracic vertebrae in order to take advantage o the (A) (B) (C) (D)

pulmonary markings heart shadow posterior ribs costal cartilages

301

34. As window level decreases (A) (B) (C) (D)

contrast scale increases contrast scale decreases brightness increases brightness decreases

35. T e AP axial projection o the chest or pulmonary apices 1. projects the apices above the clavicles 2. requires 15 to 20 degrees o cephalad angulation 3. should demonstrate the medial ends o the clavicles equidistant rom the vertebral column (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

36. Rapid onset o severe respiratory or cardiovascular symptoms a er ingestion or injection o a drug, vaccine, contrast agent, or ood or a er an insect bite describes (A) (B) (C) (D)

asthma anaphylaxis myocardial in arction rhinitis

37. Which o the lines indicated in Figure 6-5 correctly demonstrates the relationship between the exposure received by the PSP and its resulting luminescence as it is laser scanned? (A) Line A is representative o PSP exposure. (B) Line B is representative o PSP exposure. (C) Neither line is representative o PSP exposure. (D) Both lines are representative o PSP exposure.

302

6: Practice Test 1

41. Body substances and uids that are considered in ectious or potentially in ectious include

5

10 4

3

10

3

10

2

10

1

10

0

1. sputum 2. synovial uid 3. cerebrospinal uid

De ns ity

A

l

c

a

e

t

i

a

v

e

m

o

u

n

t

10

u

m

i

n

I

e

P

s

'

s

c

e

r

e

n

2

1

l

B

10

-2

-1

0

1

10 10 10 Expos ure dos e (mR)

10

2

10

3

Figure 6-5. Courtesy FUJIFILM Medical Systems USA, Inc.

38. T e ollowing is/are used to indicate the appropriateness o radiation intensity reaching the IR 1. exposure index 2. sensitivity (S) number 3. eld o view (FOV) (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

39. Which o the ollowing is most use ul or bone age evaluation? (A) (B) (C) (D)

Lateral skull PA chest AP pelvis PA hand

40. What lies immediately under the phosphor layer o a PSP storage plate? (A) (B) (C) (D)

Re ective layer Base Antistatic layer Lead oil

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

42. T e National Council on Radiation Protection and Measurements (NCRP) has recommended what total equivalent dose limit to the embryo/ etus? (A) (B) (C) (D)

0.5 mSv 5.0 mSv 50 mSv 500 mSv

43. Fluids and medications are administered to patients intravenously or which o the ollowing reasons? 1. o promote rapid response. 2. o administer parenteral nutrition. 3. o achieve a local e ect. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

44. Which o the ollowing is (are) tested as part o a QC program? 1. Beam alignment 2. Reproducibility 3. Linearity (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

Questions: 38–52

45. T e line- ocus principle re ers to the act that (A) x-rays cannot be ocused (B) x-rays travel in straight lines (C) the e ective ocal spot is larger than the actual ocal spot (D) the actual ocal spot is larger than the e ective ocal spot 46. Which o the ollowing positions will move the undus o the gallbladder shown in Figure 6-6 away rom the superimposed transverse process? (A) (B) (C) (D)

RAO LAO LPO Le lateral decubitus

303

48. T e roentgen, as a unit o measurement, expresses (A) (B) (C) (D)

absorbed dose exposure in air dose equivalent dose to biologic material

49. Histogram appearance can be skewed i there is inaccuracy in 1. part centering 2. part positioning 3. processing algorithm selection (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

50. Bone densitometry is o en per ormed to 1. measure degree o bone (de)mineralization 2. evaluate results o osteoporosis treatment/ therapy 3. evaluate condition o so tissue adjacent to bone (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

51. Indirect modes o disease transmission include 1. vector 2. omite 3. airborne (A) (B) (C) (D) Figure 6-6. Courtesy o Stam ord Hospital, Department o Radiology.

47. Which o the ollowing e ects does an analgesic have on the body? (A) (B) (C) (D)

Decreases pain Helps delay clotting Increases urine output Combats bacterial growth

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

52. I a part received 0.8 rad during a 4-minute uoroscopic examination, what was the dose rate? (A) (B) (C) (D)

2 mrad/min 20 mrad/min 200 mrad/min 2,000 mrad/min

304

6: Practice Test 1

53. An increase rom 78 to 92 kVp will result in a decrease in which o the ollowing? 1. Wavelength 2. Beam intensity 3. Energy (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

54. In the 45-degree medial oblique projection o the ankle, the 1. talotibial joint is visualized 2. tibio bular joint is visualized 3. plantar sur ace should be perpendicular to the lower leg (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

55. Major e ect(s) o irradiation o macromolecules include(s) 1. point lesions 2. cross-linking 3. main-chain scission (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

56. Cells described as somatic include 1. spermatozoa 2. neuron 3. muscle (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

57. An animal host o an in ectious organism that transmits the in ection via a bite or sting is a (A) (B) (C) (D)

vector omite host reservoir

58. I the exposure rate at 2.0 m rom a source o radiation is 18 mR/min, what will be the exposure rate at 5 m rom the source? (A) (B) (C) (D)

2.8 mR/min 4.5 mR/min 18 mR/min 85 mR/min

59. Methods o decreasing patient dose during uoroscopic examinations and include 1. use o last image hold 2. using the lowest practical pulse rate 3. keeping the patient/part as close to the image intensi er as possible (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

60. An axial projection o the clavicle is o en help ul in demonstrating a racture that is not visualized using a perpendicular CR. When examining the clavicle in the PA position, how is the CR directed or the axial projection? (A) (B) (C) (D)

Cephalad Caudad Medially Laterally

61. An exposure was made using 600 mA, 0.04-s exposure, and 85 kVp. Each o the ollowing changes will serve to decrease the receptor exposure by one-hal except a change to (A) (B) (C) (D)

1/50-s exposure 72 kVp 18 mAs 300 mA

Questions: 53–70

62. All the ollowing are rules o good body mechanics except (A) (B) (C) (D)

keep back straight, avoid twisting keep the load away rom the body push, do not pull, the load keep a wide base o support

63. Which o the ollowing is (are) accurate positioning or evaluation criteria or an AP projection o the normal knee? 1. Femorotibial interspaces equal bilaterally. 2. Patella superimposed on distal tibia. 3. CR enters 1⁄2 inch distal to base o patella. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

64. T e source-to-table distance in uoroscopy must (A) (B) (C) (D)

xed/stationary

be at least 15 inches not exceed 15 inches be at least 12 inches not exceed 12 inches

67. Images use ul in demonstrating postspinal usion degree o motion include 1. AP exion and extension 2. lateral exion and extension 3. AP right and le bending (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

68. A blowout racture usually occurs in which aspect o the orbital wall? (A) (B) (C) (D)

Superior In erior Medial Lateral

69. What is the name o the structure indicated as number 7 in Figure 6-7? (A) Lateral epicondyle (B) Medial epicondyle (C) Olecranon process (D) rochlea

65. Each o the ollowing statements regarding respiratory structures is true except (A) (B) (C) (D)

305

5

1

6

the le lung has two lobes the lower portion o the lung is the base each lung is enclosed in peritoneum the main stem bronchus enters the lung hilum

2

7

8 3

66. Which o the ollowing arti acts is occasionally associated with the use o grids in digital imaging? (A) (B) (C) (D)

Incomplete erasure Aliasing Image ading Vignetting

4

Figure 6-7.

70. Which o the ollowing projections/positions would best demonstrate structure number 8 seen in Figure 6-7? (A) (B) (C) (D)

PA projection Lateral projection AP external oblique AP internal oblique

306

6: Practice Test 1

71. T e condition in which pulmonary alveoli lose their elasticity and become permanently in ated, causing the patient to consciously exhale, is (A) (B) (C) (D) 72.

bronchial asthma bronchitis emphysema tuberculosis

ungsten alloy is the usual choice o target material or radiographic equipment because it 1. has a high atomic number 2. has a high melting point 3. can readily dissipate heat (A) (B) (C) (D)

76. A parallel plate ionization chamber receiving a charge rom x-ray photons is a/an (A) (B) (C) (D)

photomultiplier tube induction motor autotrans ormer AEC

77. In which o the ollowing projections was the image in Figure 6-8 made? (A) (B) (C) (D)

AP Medial/internal oblique Lateral/external oblique Acute exion

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

73. T e portion o a hypodermic needle that attaches to the syringe is termed its (A) (B) (C) (D)

hub gauge length bevel

74. X-ray tube li e may be extended by 1. using high mAs with low kV technical actors 2. avoiding lengthy anode rotation 3. avoiding exposures to a cold anode (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

75. Gonadal shielding should be provided or male patients in which o the ollowing examinations? 1. Femur 2. Abdomen 3. Pelvis (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Figure 6-8.

78. Which o the ollowing statements is (are) true with respect to the di erences between the male and emale bony pelvis? 1. T e emale pelvic outlet is wider. 2. T e pubic angle is 90 degrees or less in the male. 3. T e male pelvis is more shallow. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Questions: 71–86

79. Which interaction between x-ray photons and matter involves partial trans er o the incident photon energy to the involved atom? (A) (B) (C) (D)

Photoelectric e ect Compton scattering Coherent scattering Pair production

80. In which section o the automatic processor shown in Figure 6-9 are the unexposed silver halide grains acted upon? (A) (B) (C) (D)

Section 1 Section 2 Section 3 Section 4

307

82. Geometric unsharpness is in uenced by which o the ollowing? 1. Distance rom object to image. 2. Distance rom source to object. 3. Distance rom source to image. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

83. A minimum total amount o aluminum ltration (inherent plus added) o 2.5 mm is required in equipment operated (A) (B) (C) (D)

above 50 kVp above 60 kVp above 70 kVp above 80 kVp

84. Which o the ollowing radiologic examinations would deliver the greatest ESE? (A) (B) (C) (D)

1

2

3

4

Figure 6-9.

81. It is essential to question emale patients o childbearing age regarding the 1. date o their last menstrual period 2. possibility o their being pregnant 3. number o x-ray examinations they have had in the past 12 months (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

Chest Skull Abdomen T oracic spine

85. Combinations o milliamperage and exposure time that produce a particular milliampere-seconds value will produce identical receptor exposures. T is statement is an expression o the (A) (B) (C) (D)

inverse-square law line- ocus principle reciprocity law D log E curve

86. T e AP projection o the scapula requires that the 1. a ected arm be abducted 2. CR enters approximately 2 in in erior to the coracoid process 3. thorax be rotated about 15 degrees toward the a ected side (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

308

6: Practice Test 1

87. How can OID be reduced or a PA projection o the wrist? (A) (B) (C) (D)

Extend the ngers. Flex the metacarpophalangeal joints. Extend the orearm. Oblique the metacarpals 45 degrees.

88. How o en are radiographic equipment collimators required to be evaluated? (A) (B) (C) (D)

Annually Biannually Semiannually Quarterly

89. During an intravenous urogram (IVU), the RPO position is used to demonstrate the 1. le kidney parallel to the IR 2. right kidney parallel to the IR 3. right kidney perpendicular to the IR (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1 and 3 only

90. Impingement on the wrist’s median nerve causing pain and disability o the a ected hand and wrist is known as (A) (B) (C) (D)

carpal boss syndrome carpal tunnel syndrome carpopedal syndrome radioulnar syndrome

91. All other actors remaining the same, i a 14 × 17 inches eld is collimated to a 4-inch–square eld, the radiographic image will demonstrate (A) (B) (C) (D)

increased receptor exposure decreased receptor exposure more detail/resolution less detail/resolution

92. A term that is o en used to describe a particular control panel so ware selection, in medical imaging is (A) (B) (C) (D)

hardware algorithm histogram modem

93. T e legal doctrine res ipsa loquitur relates to which o the ollowing? (A) (B) (C) (D)

Let the master answer. T e thing speaks or itsel . A thing or matter settled by justice. A matter settled by precedent.

94. What should be done to correct or magni cation when using air-gap technique? (A) (B) (C) (D)

Decrease OID Increase OID Decrease SID Increase SID

95. In the AP projection o an asthenic patient whose knee measures less than 19 cm rom the anterosuperior iliac spine (ASIS) to tabletop, the CR should be directed (A) (B) (C) (D)

perpendicularly 5 degrees medially 5 degrees cephalad 5 degrees caudad

96. Which o the ollowing statements is (are) true regarding Figure 6-10? 1. Poor centering is evident. 2. High contrast is demonstrated. 3. Inadequate penetration is evident. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Questions: 87–103

309

100. For which o the ollowing can a radiographer be ound liable or a negligent tort? 1. Radiographer images the wrong orearm. 2. Patient is injured while being positioned on the x-ray table. 3. Radiographer ails to question patient about possible pregnancy be ore per orming x-ray examination. (A) (B) (C) (D) 101.

Figure 6-10. Courtesy o Stam ord Hospital, Department o Radiology.

97. T e x-ray image seen on the computer display monitor is a (an) (A) (B) (C) (D)

analog image digital image phosphor image emulsion image

98. Which o the ollowing a ect(s) both the quantity and quality o the primary beam? 1. Hal -value layer (HVL) 2. Kilovoltage 3. Milliamperage (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

99. Which o the ollowing groups o organs/structures are located in the le upper quadrant? (A) Le kidney, le suprarenal gland, and gastric undus. (B) Le suprarenal gland, pylorus, and duodenal bulb. (C) Hepatic exure, cecum, and pancreas. (D) Gastric undus, liver, and cecum.

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

echnical actors o 100 kVp and 6 mAs are used with a 6:1 grid or a particular exposure. What should be the new milliampere-seconds value i a 12:1 grid is substituted? (A) (B) (C) (D)

7.5 mAs 10 mAs 13 mAs 18 mAs

102. A diabetic patient who has not taken insulin while preparing or a asting radiologic examination is susceptible to a hypoglycemic reaction. T is is characterized by 1. atigue 2. cyanosis 3. restlessness (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

103. Which o the ollowing is (are) located on the proximal aspect o the humerus? 1. Intertubercular groove 2. Capitulum 3. Coronoid ossa (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

310

6: Practice Test 1

104. I the lumbar apophyseal articulation is not well visualized in the posterior oblique position, and the pedicle is seen on the posterior aspect o the vertebral body, what should be done to correct the position? (A) (B) (C) (D)

106. A controlled area is one that is (A) restricted to access by nonradiation workers only (B) monitored by survey meters (C) occupied by radiation workers (D) occupied by the general population

Increase the degree o patient rotation. Decrease the degree o patient rotation. Flex knees to decrease lordotic curve. Angle 5 to 7 degrees cephalad.

107.

105. Which o the ollowing is/are associated with magni cation uoroscopy?

(A) (B) (C) (D)

1. Less noise 2. Improved contrast resolution 3. Improved spatial resolution (A) (B) (C) (D)

A

echnical actors o 400 mA, 20 ms, 68 kVp at 40-inch SID were used to produce a satis actory SF/analog x-ray image. A change to 4 mAs can be best compensated or by which o the ollowing?

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Increasing the SID to 60 inches Decreasing the SID to 20 inches Decreasing the kilovoltage to 60 Increasing the kilovoltage to 78 kVp

108. Which o the ollowing statements re erring to Figure 6-11 is (are) correct? (A) (B) (C) (D)

Image A was per ormed AP. Image B was per ormed AP. Both images were obtained in the AP position. Neither image was obtained in the AP position.

B

Figure 6-11. Courtesy o Stam ord Hospital, Department o Radiology.

Questions: 104–115

109. Ionizing radiation passing through tissue and depositing energy through ionization processes is known as (A) (B) (C) (D)

the characteristic e ect Compton scatter linear energy trans er the photoelectric e ect

110. T e radiograph shown in Figure 6-12 can be produced with the 1. long axis o the plantar sur ace perpendicular to the IR 2. CR 40 degrees cephalad to the base o the third metatarsal 3. CR 20 degrees cephalad to the talotibial joint (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1 and 3 only

311

112. T e geometric actors impacting image quality include 1. spatial resolution 2. distortion 3. gray scale (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

113. T e brightness level o the uoroscopic image can vary with changes in 1. milliamperage 2. kilovoltage 3. patient thickness (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

114. Which o the ollowing methods can be used to decrease the e ect o di erential absorption, especially in SF/analog imaging? 1. Using high kV and low mAs 2. Using compensating ltration 3. Using actors that increase the photoelectric e ect (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

115. T e line- ocus principle expresses the relationship between Figure 6-12. Courtesy o Stam ord Hospital, Department o Radiology.

111. Which o the ollowing interactions between x-ray photons and matter is most responsible or patient dose? (A) (B) (C) (D)

T e photoelectric e ect Compton scatter Classic scatter T ompson scatter

(A) actual and e ective ocal spot (B) SID used and resulting receptor exposure (C) exposure given the IR and resulting brightness (D) kilovoltage level and resulting degree o penetration

312

6: Practice Test 1

116. Compared with that o the hypersthenic and sthenic body types, the gallbladder o an asthenic patient is most likely to be located (A) (B) (C) (D)

higher and more medial lower and more medial higher and more lateral lower and more lateral

117. Which o the ollowing correctly identi es the letter in the radiograph shown in Figure 6-13? (A) (B) (C) (D)

118. Which o the ollowing correctly identi es the letter S in the radiograph shown in Figure 6-13? (A) (B) (C) (D)

119. T e RPO position o the cervical spine requires which o the ollowing combinations o tube angle and direction? (A) (B) (C) (D)

Plane joint Spheroid joint Sellar joint Ellipsoid joint

Plane joint Spheroid joint Sellar joint Ellipsoid joint

25 to 30 degrees cephalad 25 to 30 degrees caudad 15 to 20 degrees cephalad 15 to 20 degrees caudad

120. Crescent-shaped black marks on a chemically processed x-ray lm are usually due to (A) (B) (C) (D)

M

121. I 300 mA has been selected or a particular exposure, what exposure time should be selected to produce 18 mAs?

G U H C N A S R

bending the lm acutely improper development improper lm storage static electricity

(A) (B) (C) (D)

40 ms 60 ms 400 ms 600 ms

122. I the center photocell were selected or a lateral projection o the lumbar spine that was positioned with the spinous processes instead o the vertebral bodies centered to the grid, how would the resulting radiograph look? (A) (B) (C) (D)

T e image would be underexposed. T e image would be overexposed. T e image would be correctly exposed. An exposure could not be made.

123. What type o shock results rom bodily invasion o in ection?

Figure 6-13. Courtesy o Bob Wong, R. T.(R).

(A) (B) (C) (D)

Septic Neurogenic Cardiogenic Hypovolemic

Questions: 116–133

124. What is the most superior structure o the scapula? (A) (B) (C) (D)

Apex Acromion process Coracoid process Superior angle

125. Which o the ollowing contribute(s) to x-ray lm base-plus og? 1. Chemical og 2. Base tint 3. Background radiation (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

126. Examples o primary radiation barriers include 1. radiographic room walls 2. radiographic room oor 3. lead aprons (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

127. T e term used to describe the gradual decrease in exposure rate as an x-ray beam passes through matter is (A) (B) (C) (D)

attenuation absorption scattered radiation secondary radiation

128. Which o the ollowing cell types has the lowest radiosensitivity? (A) (B) (C) (D)

Nerve cells Muscle cells Spermatids Lymphocytes

313

129. A cathartic is used to (A) (B) (C) (D)

induce vomiting stimulate de ecation promote elimination o urine inhibit coughing

130. Although the stated ocal-spot size is measured directly under the actual ocal spot, ocal-spot size in act varies along the length o the x-ray beam. At which portion o the x-ray beam is the e ective ocal spot the largest? (A) (B) (C) (D)

At its outer edge Along the path o the CR At the cathode end At the anode end

131. Extravasation occurs when (A) there is an absence o collateral circulation (B) there is a multitude o vessels supplying one area (C) excessive contrast medium is injected (D) contrast medium is injected into surrounding tissue 132. What is the best position/projection to demonstrate the longitudinal arch o the oot? (A) (B) (C) (D)

Mediolateral Lateromedial Mediolateral weight-bearing lateral Lateromedial weight-bearing lateral

133. What anatomic structure is indicated by the letter K in Figure 6-14? (A) (B) (C) (D)

Lesser trochanter Sacroiliac joint Greater sciatic notch Obturator oramen

314

6: Practice Test 1

137. T e cycle o in ection includes which o the ollowing components?

A B

1. Reservoir o in ection 2. Pathogenic organism 3. Means o transmission

K

C

(A) (B) (C) (D)

D

J

G

I

E

H F

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

138. Which o the ollowing conditions will require an increase in x-ray photon energy/penetration? (A) (B) (C) (D)

Fibrosarcoma Osteomalacia Paralytic ileus Ascites

139. T e medical term used to describe the vomiting o blood is

Figure 6-14. Photo Contributor: Stam ord Hospital, Department o Radiology.

134. What is the minimum requirement or lead aprons, according to CFR 20? (A) (B) (C) (D)

0.05 mm Pb 0.50 mm Pb 0.25 mm Pb 1.0 mm Pb

135. T e type o isolation practiced to prevent the spread o in ectious agents in aerosol orm is (A) (B) (C) (D)

respiratory isolation protective isolation contact isolation strict isolation

136. Stochastic e ects o radiation include (A) (B) (C) (D)

blood changes genetic alterations cataractogenesis reduced ertility

(A) (B) (C) (D)

hematemesis hemoptysis hematuria epistaxis

140. T e position most likely to o er the best visualization o the pulmonary apices is the (A) (B) (C) (D)

lateral decubitus dorsal decubitus erect lateral AP axial lordotic

141. Which o the ollowing is used to obtain a lateral projection o the upper humerus on patients who are unable to abduct their arm? (A) Bicipital groove projection (B) Superoin erior lateral (C) In erosuperior axial (D) ransthoracic lateral

Questions: 134–150

142. T e term di erential absorption is related to

146. Grid interspace material can be made o

1. beam intensity 2. subject contrast 3. pathology

1. plastic 2. lead 3. aluminum

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

143. Which o the ollowing is (are) demonstrated in the lateral projection o the thoracic spine? 1. Intervertebral spaces 2. Apophyseal joints 3. Intervertebral oramina (A) (B) (C) (D)

1 only 2 only 1 and 3 only 1, 2, and 3

144. Which o the ollowing positions would demonstrate the right lumbar apophyseal articulations closest to the IR? (A) (B) (C) (D)

LAO RAO LPO RPO

145. Features o digital uoroscopy (DF) that contribute to patient dose reduction include 1. last image hold 2. pulsed exposure 3. longer procedure times (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

315

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

147. What is the annual workers? (A) (B) (C) (D)

EDE limit or radiation

5 mSv 500 mSv 5,000 mSv 50 mSv

148. All the ollowing statements regarding beam restriction are true except (A) beam restriction improves contrast resolution (B) beam restriction improves spatial resolution (C) eld size should never exceed IR dimensions (D) beam restriction reduces patient dose 149. An increase in technical actors usually is required in which o the ollowing circumstances? 1. Edema 2. Ascites 3. Acromegaly (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

150. Verbal disclosure o con dential in ormation that is detrimental to the patient is re erred to as (A) (B) (C) (D)

invasion o privacy slander libel assault

316

6: Practice Test 1

151. Which o the ollowing medications commonly ound on emergency carts unctions to raise blood pressure? (A) (B) (C) (D)

L

Heparin Norepinephrine Nitroglycerin Lidocaine

2 3 4

152. Focal-spot blur is greatest (A) (B) (C) (D)

toward the anode end o the x-ray beam toward the cathode end o the x-ray beam directly along the course o the CR as the SID is increased

153. Advantages o coupling the image intensi er to the V camera or CCD via a ber-optic coupling device include its 1. compact size 2. durability 3. ability to accommodate auxiliary imaging devices (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

154. Occupational exposure received by the radiographer is mostly rom (A) (B) (C) (D)

Compton scatter the photoelectric e ect coherent scatter pair production

155. T e part labeled number 4 in Figure 6-15 is (A) (B) (C) (D)

cuboid sesamoid tuberosity lateral cunei orm

1

5

7

6

Figure 6-15. Courtesy o Stam ord Hospital, Department o Radiology.

156. Sternal compressions during CPR are made with the heels o the hands located about (A) (B) (C) (D)

11⁄2 inches superior to the xiphoid tip 11⁄2 inches in erior to the xiphoid tip 3 inches superior to the xiphoid tip 3 inches in erior to the xiphoid tip

157. How is the introduction o a 6-inch OID likely to a ect receptor exposure? (A) (B) (C) (D)

Receptor exposure would increase. Receptor exposure would decrease. Receptor exposure would be unchanged. Receptor exposure and OID unrelated.

158. Which o the ollowing may be used as landmark(s) or an AP projection o the hip? 1. 2 inches medial to the ASIS 2. Prominence o the greater trochanter 3. Midway between the iliac crest and the pubic symphysis (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

Questions: 151–168

159. I 32 mAs was used to produce a particular screen/ lm x-ray image, what new mAs value would be required to produce a similar image i the kV was increased by 15%? (A) (B) (C) (D)

8 mAs 16 mAs 32 mAs 64 mAs

160. Recommended method(s) o minimizing motion unsharpness include 1. suspended respiration 2. short exposure time 3. patient instruction (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

161. Oral administration o barium sul ate suspension is usually required to demonstrate the ollowing structure(s) 1. Descending duodenum 2. Ilium 3. Splenic exure (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 3 only

162. T e unction o the developer solution chemicals is to (A) (B) (C) (D)

reduce the mani est image to a latent image increase production o silver halide crystals reduce the latent image to a mani est image remove the unexposed crystals rom the lm

163. T e image intensi er’s input phosphor di ers rom the output phosphor in that the input phosphor (A) is much larger than the output phosphor (B) emits electrons, whereas the output phosphor emits light photons (C) absorbs electrons, whereas the output phosphor absorbs light photons (D) is a xed size, and the size o the output phosphor can vary

317

164. Minor reactions to IV administration o a contrast agent can include 1. a ew hives 2. nausea 3. a ushed ace (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

165. In an AP abdomen radiograph taken at 105-cm SID during an IVU series, one renal shadow measures 9 cm in width. I the OID is 18 cm, what is the actual width o the kidney? (A) (B) (C) (D)

5 cm 7.5 cm 11 cm 18 cm

166. During measurement o blood pressure, which o the ollowing occurs as the radiographer controls arterial tension with the sphygmomanometer? (A) (B) (C) (D)

T e brachial vein is collapsed. T e brachial artery is temporarily collapsed. T e antecubital vein is monitored. Oxygen saturation o arterial blood is monitored.

167. A lesion with a stalk projecting rom the intestinal mucosa into the lumen is a(n) (A) stula (B) polyp (C) diverticulum (D) abscess 168. Which o the x-ray circuit devices shown in Figure 6-16 operates on the principle o sel -induction? 1. Number 1 2. Number 2 3. Number 3 (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

318

6: Practice Test 1 A

B

C

1

–

3

2

5

4 7

+

6

Figure 6-16.

169. Re erring to the simpli ed x-ray circuit shown in Figure 6-16, what is indicated by the number 4? (A) (B) (C) (D)

Step-up trans ormer Kilovoltage meter Grounded milliamperage meter Recti cation system

170. Which o the ollowing pathologic conditions are considered additive conditions with respect to selection o technical actors? 1. Osteoma 2. Bronchiectasis 3. Pneumonia (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

171. Which o the ollowing would be most likely to cause the greatest skin dose (ESE)? (A) (B) (C) (D)

Short SID High kilovoltage Increased ltration Increased milliamperage

172. Which o the ollowing is (are) essential to high-quality mammographic examinations? 1. Small ocal-spot x-ray tube 2. Short-scale contrast 3. Use o a compression device (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

173. When medications are administered parenterally, they are given (A) (B) (C) (D)

orally orally or intravenously intravenously or intramuscularly by any route other than orally

174. I 84 kV and 8 mAs were used or a particular abdominal exposure with single-phase equipment, what milliampere-seconds value would be required to produce a similar radiograph with three-phase, 12-pulse equipment? (A) (B) (C) (D)

24 mAs 16 mAs 8 mAs 4 mAs

Questions: 169–184

175. A ocal-spot size o 0.3 mm or smaller is essential or which o the ollowing procedures? (A) Bone radiography (B) Magni cation radiography (C) omography (D) Fluoroscopy 176. What type o x-ray imaging uses an area beam and a photostimulable phosphor as the IR? (A) (B) (C) (D)

SF/analog radiography Computed radiography Digital radiography Cineradiography

1. light 2. dark 3. noisy (A) (B) (C) (D)

(A) (B) (C) (D)

1. Ribs 2. Vertebrae 3. Shoulder (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

(A) (B) (C) (D)

eld must

10% o the OID 2% o the OID 10% o the SID 2% o the SID

182. T e use o which o the ollowing is (are) essential in magni cation radiography? 1. High-ratio grid 2. Fractional ocal spot 3. Direct exposure technique

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

178. T e principal unction o tube is to reduce

180. Which o the ollowing adult radiographic examinations usually require(s) use o a grid?

181. T e x-ray beam and collimator light coincide to within

177. Inadequate collimation in CR imaging can result in an image that is too

319

ltration in the x-ray

patient skin dose operator exposure scattered radiation image noise

179. T e e ects o radiation on biologic material depend on several actors. I a quantity o radiation is delivered to a body over a long period o time, the e ect (A) will be greater than i it is delivered all at one time (B) will be less than i it is delivered all at one time (C) has no relation to how it is delivered in time (D) solely depends on the radiation quality

(A) (B) (C) (D)

1 only 2 only 1 and 3 only 1, 2, and 3

183. Which o the ollowing shoulder projections can be used to evaluate the lesser tubercle in pro le? (A) (B) (C) (D)

External rotation position Internal rotation position Neutral rotation position In erosuperior axial position

184. Which type o error results in grid cuto at the periphery o the radiographic image? (A) (B) (C) (D)

O O O O

- ocus -center -level -angle

320

6: Practice Test 1

185. Which o the ollowing structures will be lled with barium in the AP recumbent position o a sthenic patient during an upper GI examination? (A) (B) (C) (D)

Duodenal bulb Descending duodenum Pyloric vestibule Gastric undus

186. T e positive electrode o the x-ray tube is the (A) (B) (C) (D)

capacitor grid cathode anode

187. Which o the ollowing techniques might have been employed in the production o Figure 6-17? 1. Motion 2. Anode heel e ect 3. Compression (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

188. Which o the ollowing pathologic conditions require(s) a decrease in technical actors? 1. Pneumothorax 2. Emphysema 3. Multiple myeloma (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

189. A diuretic is used to (A) (B) (C) (D)

induce vomiting stimulate de ecation increase urine output inhibit coughing

190. An exposed image plate will retain its image or about (A) (B) (C) (D)

2 hours 8 hours 24 hours 48 hours

191. T e total number o x-ray photons produced at the target is contingent on the 1. tube current 2. target material 3. square o the kilovoltage (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

192. Which o the ollowing ormulas would the radiographer use to determine the total number o heat units (HU) produced with a given exposure using three-phase, 12-pulse equipment? (A) (B) (C) (D) Figure 6-17. Reproduced, with permission, rom Shephard CT. Radiographic Image Production and Manipulation. New York: McGraw-Hill; 2003.

mA × mA × mA × mA ×

kVp × kVp × kVp × kVp ×

s s × 3.0 s × 1.35 s × 1.41

Questions: 185–200

193. Which o the ollowing positions would best demonstrate the lumbar intervertebral joints and oramina? (A) (B) (C) (D)

197. Which o the ollowing terms is used to express resolution? (A) (B) (C) (D)

LPO RPO Lateral PA

(A) (B) (C) (D)

stored in a radiation- ree area kept in a designated control booth kept in the lm-processing area used as an extra badge or new personnel

195. What is the appropriate action i a patient has signed consent or a procedure but, once on the radiographic table, re uses the procedure? (A) Proceed—the consent orm is signed. (B) Send the patient back to his or her room. (C) Honor the patient’s request and proceed with the next patient. (D) Immediately stop the procedure and in orm the radiologist and the re erring physician o the patient’s request. 196.

o release electrons when heated. o release light when heated. o direct electrons to the ocal track. o direct light to the ocal track.

199. O what material is the x-ray tube component numbered 5 in Figure 6-18 made? (A) Cesium (B) Copper (C) Nickel (D) ungsten 200. O what material is the x-ray tube component numbered 2 in Figure 6-18 made? (A) Cesium (B) Copper (C) Molybdenum (D) ungsten

o maintain image clarity, the path o electron ow rom photocathode to output phosphor is controlled by (A) (B) (C) (D)

Kiloelectronvolts (keV) Modulation trans er unction (M F) Relative speed Latitude

198. What is the unction o the x-ray tube component numbered 2 in Figure 6-18?

194. T e control dosimeter that comes rom the monitoring company should be (A) (B) (C) (D)

321

the accelerating anode electrostatic lenses the vacuum glass envelope the input phosphor 4 3

1 2 5

Figure 6-18.

Answers and Explanations

1. (C) Computed radiography (CR) cassettes use no intensi ying screens or lm—hence, the term lmless radiography. T e Image Plates (IPs) have a protective unction ( or the PSP/storage plate within) and can be used in the Bucky tray or directly under the anatomic part; they need not be light-tight because the PSP is not light sensitive. T e IP has a thin lead- oil backing (similar to traditional cassettes) to absorb backscatter. Inside the IP is the photostimulable phosphor (PSP) storage plate. T is PSP storage plate within the IP has a layer o europium-activated barium uorohalide that serves as the IR as it is exposed in the traditional manner and receives the latent image. T e PSP can store the latent image or several hours; a er about 8 hours, noticeable image ading will occur. 2. (A) Assault is the threat o touching or harming, with the apparent ability to carry out the threat. I a patient eels threatened by a healthcare provider either because o the provider’s tone or pitch o voice or because o words that are threatening, an assault charge may be made. Battery re ers to the unlaw ul laying o hands on a patient. Battery could be charged i a patient were moved about roughly or touched in a manner that is inappropriate or without the patient’s consent. False imprisonment may be considered i a patient states that he or she no longer wishes to continue with a procedure and is ignored or i restraining devices are used improperly or used without a physician’s order. Invasion-o -privacy issues arise when there has been a disclosure o con dential in ormation.

322

3. (B) When the patient is unable to ully extend their elbow as a result o injury, an AP projection o the bony structures is still required. In this situation, two projections are necessary–one projection or the distal humerus and one projection or the proximal orearm. T e proximal orearm elbow structures are demonstrated with the orearm parallel to the IR and a perpendicular CR as seen in the gure. T e distal humerus elbow structures are demonstrated with the humerus parallel to the IR and a perpendicular CR. I the elbow is exed to a greater degree, the CR can be directed 10 to 15 degrees into the joint space. 4. (B) Anaphylaxis is an acute reaction characterized by sudden onset o urticaria, respiratory distress, vascular collapse, or systemic shock; it sometimes leads to death. It is caused by ingestion or injection o a sensitizing agent such as a drug, vaccine, contrast agent, or ood or by an insect bite. Asthma is characterized by dif culty in breathing, causing bronchospasm. It is o en precipitated by stress, and although dyspnea is a symptom, oxygen is not administered. Asthmatics carry a nebulizer that contains a medication to relieve the bronchospasm, thereby relieving their breathing distress. Asthma and rhinitis are examples o allergic reactions. 5. (B) As the CR laser scanner/reader recognizes the phosphostimulated luminescence (PSL) released by the PSP storage plate, it constructs a graphic representation o pixel value distribution called a histogram. T e photostimulable storage phosphor (PSP) within the IP is the image receptor (IR). T e PSP is

Answers: 1–9

a europium-doped barium uorohalide coated storage plate. When the PSP is exposed by x-ray photons, the x-ray energy interacts with the crystals and a small amount o visible light is emitted, but most o the x-ray energy is stored (hence, the term storage plate). T is stored energy represents the latent image. T e IP is placed in the CR scanner/reader where a helium–neon, or solid-state, laser beam scans the PSP and its stored energy is released as blue-violet light (phosphostimulated luminescence [PSL]). T is light signal represents varying tissue densities and the latent image that is then transerred to an analog-to-digital converter (ADC)— converting the signal to a digital (electrical) one to be displayed on a monitor. T e PSL values will result in numerous image brightness values that represent various tissue densities (i.e., x-ray attenuation properties), or example, bone, muscle, blood- lled organs, air/gas, pathologic processes, and so on. T e CR scanner/ reader recognizes all these values and constructs a representative gray-scale histogram o them corresponding to the anatomical characteristics o the imaged part. T us, all PA chest histograms will be similar, all lateral chest histograms will be similar, all pelvis histograms will be similar, and so on. A histogram is a graphic representation o pixel-value distribution. T e histogram analyzes all the densities rom the PSP and represents them graphically—demonstrating the quantity o exposure, the number o pixels, and their value. Histograms are generated that are unique to each body part that can be imaged. A er a part is exposed/imaged, its PSP is read/ scanned and its own histogram is developed and analyzed. T e resulting analysis, and histogram o the actual imaged part, is compared to the programmed representative histogram or that part. Over time, i required diagnostic image characteristics change, a histogram can be updated to re ect the latest required characteristics. 6. (D) T e 45-degree oblique position o the lumbar spine generally is per ormed or demonstration o the apophyseal joints. In a correctly positioned oblique lumbar spine, “Scotty dog” images are demonstrated. T e Scotty’s ear corresponds to the superior articular process, his nose to the transverse process, his eye to the pedicle, his neck to the

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pars interarticularis, his body to the lamina, and his ront oot to the in erior articular process. 7. (D) According to the inverse-square law o radiation, the intensity or exposure rate o radiation rom its source is inversely proportional to the square o the distance. T us, as distance rom the source o radiation increases, exposure rate decreases. I the distance between the x-ray source and the image receptor is doubled, the image receptor will receive one- ourth o the original x-ray value. 8. (B) X-ray images are o en subpoenaed as court evidence in cases o medical litigation. In order to be considered as legitimate legal evidence, each x-ray image must contain certain essential and speci c patient in ormation. Essential in ormation that must be included on each image is patient identi cation, the identity o the acility where the x-ray study was per ormed, the date that the study was per ormed, and a right- or le -side marker. Other use ul in ormation that may be included, but that is not considered essential, is additional patient demographics such as their date o birth, the identity o the re erring physician, the time o day that the study was per ormed, and the identity/initials o the radiographer per orming the examination. 9. (D) A cross-sectional image o the abdomen is shown in the gure. T e large, homogeneous structure on the right, labeled 14, is the liver. T e gallbladder is o en seen on the medial border o the liver but is not visualized here. T e le kidney is labeled 5; the right kidney is seen clearly on the opposite side labeled 11. T e vertebra is seen in the posterior center, and the psoas muscles are seen just posterior to the vertebra. Just anterior to the body o the vertebra is the circular aorta, labeled 7. T e in erior vena cava (number 12) is seen to the le o the aorta. T e circular structure just anterior to the in erior vena cava is the portal vein (number 13). Number 1 is the stomach, number 2 is the splenic/le colic exure, number 3 is the pancreas, and number 4 is the spleen. Numbers 6 and 10 are portions o the le and right adrenal glands—not normally seen at this level. Number 8 is the celiac trunk; the common hepatic artery is seen branching to the right, and the splenic artery is seen branching to the le . Number 9 is a part o the diaphragmatic crura connecting the vertebrae and diaphragm.

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10. (C) Late or long-term e ects o radiation can occur in tissues as a result o chronic exposure or tissues that have survived a previous irradiation months or years earlier. T ese late e ects, such as carcinogenesis and genetic e ects, are “all-ornothing” e ects—either the organism develops cancer or it does not. Most late e ects do not have a threshold dose; that is, any dose, however small, can induce an e ect (thus, the importance o radiation protection). Increasing that dose will increase the likelihood o the occurrence but will not a ect its severity; these e ects are termed stochastic. Nonstochastic e ects are those that will not occur below a particular threshold dose and that increase in severity as the dose increases. Early e ects o radiation exposure are in response to relatively high radiation doses. T ese never should occur in diagnostic radiology; they occur only in response to doses much greater than those used in diagnostic radiology. One o the e ects that may be noted in such a circumstance is the hematologic e ect—reduced numbers o white blood cells, red blood cells, and platelets in the circulating blood. Immediate local tissue e ects can include e ects on the gonads (temporary in ertility) and on the skin (e.g., epilation and erythema). Acute radiation lethality, or radiation death, occurs a er an acute exposure and results in death in weeks or days. 11. (C) Contrast-medium injection into the ureters can be achieved only by rst catheterizing the bladder, locating the ureteral ori ces, and then injecting the contrast agent into the ureters. T is procedure is called a retro grade (because contrast is being introduced against the normal direction o ow) pyelogram. A cystogram is an examination o the bladder. A cystourethrogram is an examination o the bladder and urethra. 12. (C) T e term kerma is used to express kinetic energy released in matter. X-rays expend kinetic energy as they ionize the air or matter. Joule/ kilogram is used to measure air kerma and 1 J/kg = 1 Gya. T e subscript a represents air as the absorber. T e mGya is the Standard International (SI) unit o measure o radiation intensity/exposure. T e rad has been described as equivalent to 100 ergs o energy deposited per gram o irradiated material. T e SI unit is Gray (Gyt)—the subscript t representing tissue.

13. (D) Radiographic rating charts enable the operator to determine the maximum sa e milliamperage, exposure time, and peak kilovoltage or a particular exposure using a particular x-ray tube. An exposure that can be made sa ely with the large ocal spot may not be sa e or use with the small ocal spot o the same x-ray tube. T e total number o heat units that an exposure generates also in uences the amount o stress (in the orm o heat) imparted to the anode. T e product o milliampere-second and peak kilovolts determines HU. Groups (A) and (C) produce 2,250 HU; groups (B) and (D) produce 1,275 HU. Groups (B) and (D) deliver less heat load, but group (D) delivers it to a larger area (actual ocal spot), making this the least hazardous group o technical actors. T e most hazardous group o technical actors is group (A). 14–15. (14, C; 15, B) T e radiograph illustrates an AP projection o the scapula; abduction o the arm moves the scapula away rom the rib cage, revealing a greater portion o the scapula than would be visualized with the arm at the side. A number o bony structures are identi ed: the acromion process (A), the humeral head (B), glenoid ossa (C), scapular spine (D), clavicle (E), supraspinatus ossa (F), acromioclavicular joint (G), scapular notch (H), coracoid process (I), in erior angle/apex (J), body/costal sur ace (K), lateral/axillary border (L), base o the scapula (M). 16. (A) Image details placed away rom the path o the CR will be exposed by more divergent rays, resulting in rotation distortion, similar to that observed when the part itsel is rotated. T is is why the CR must be directed to the midpoint o the part o greatest interest. For example, i bilateral hands are requested, they should be examined individually; i imaged simultaneously, the CR will be directed to no anatomic part (between the two hands) and rotation distortion will occur. Magni cation occurs when an OID is introduced, or with a decrease in SID. Foreshortening and elongation are the two types o shape distortion—caused by nonalignment o the x-ray tube, part/subject, and IR. 17. (C) Federal regulations regarding in ection control in the workplace, as amended by OSHA, require development o policies con orming to OSHA

Answers: 10–25

guidelines and instruction in their application/use. T ese regulations also require provision o hepatitis B immunization ( ree o charge) or all sta who might be exposed to blood/body substances, ollow-up care or any sta accidentally exposed to blood/body uids and/or needle stick injuries, and readily accessible personal protective equipment (PPE) and impermeable puncture-proo containers or used needles/syringes. It also requires that all healthcare workers and their employers ollow/ en orce standard precautions, transmission-based precautions, and these OSHA guidelines under penalty o law. 18. (D) Atelectasis is partial or complete collapse (i.e., imper ect expansion) o a lung or lobe o a lung. Pneumonia is an acute in ection o the lung parenchyma characterized by productive cough, chest pain, ever, and chills and requently accompanied by rales. Pneumothorax is the condition o air or gas in the pleural space. Chronic obstructive pulmonary disease (COPD) is the name given to a number o disease processes that decrease the lung’s ability to per orm its unction o ventilation. 19. (C) o have high diagnostic quality, a barium enema (BE) examination requires rigorous and complete patient preparation. T is usually consists o a modi ed low-residue diet or a ew days be ore the examination, cathartics the day be ore, and cleansing enemas the morning o the examination. Instructions or an upper GI series, small bowel series, and IV cystogram are usually to be NPO a er midnight. 20. (B) Quality Control re ers to our equipment and its sa e and accurate operation. Various components must be tested at speci ed intervals and test results must be within speci ed parameters. Any deviation rom those parameters must be corrected. Examples o equipment components that are tested annually are the ocal-spot size, linearity, reproducibility, ltration, kV, and exposure time. T ree-phase x-ray generators should be able to time exposures to + /− 5% accuracy. Radiographic equipment collimators should be inspected and veri ed as accurate semiannually (twice a year); the relationship between the collimator light eld and the actual x-ray eld must be congruent to within 2% o the SID. Kilovoltage settings can most e ectively be tested using an electronic kV meter; to meet required

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standards, the kV should be accurate to within + /− 4 kV. Reproducibility testing should speci y that radiation output be consistent to within + /− 5%. 21. (D) T e protective curtain, usually made o leaded vinyl with at least 0.25-mm Pb equivalent, must be positioned between the patient and the uoroscopist to greatly reduce exposure o the uoroscopist to energetic scatter rom the patient. As with overhead equipment, uoroscopic total ltration must be at least 2.5-mm Al equivalent to reduce excessive exposure to so radiation. Collimator/beam alignment must be accurate to within 2%. 22. (D) In the AP projection o the lumbar spine, the disk spaces o L1 to L4 are perpendicular to the IR and well visualized, but the L5 to S1 disk space is angled 30 to 35 degrees cephalad to the perpendicular. I the CR is directed 30 to 35 degrees cephalad midway between the ASIS and the pubis symphysis, the L5 to S1 interspace will be well demonstrated. 23. (A) When the arm is placed in the AP position, the epicondyles are parallel to the plane o the cassette, and the shoulder is placed in external rotation. In this position, an AP projection o the humerus, elbow, and orearm can be obtained. For the lateral projection o the humerus, elbow, or orearm, the epicondyles must be perpendicular to the plane o the cassette. 24. (D) Endoscopic retrograde cholangiopancreatography (ERCP) is per ormed to diagnose disease o the biliary and/or pancreatic organs. Fluoroscopic control is used to introduce the ber-optic endoscope through the mouth and into the duodenum. T e hepatopancreatic ampulla (o Vater) then is located and cannulated, and contrast medium is injected into the common bile duct. 25. (A) T e cervical intervertebral oramina (and the pedicles that orm them) orm a 45-degree angle with the MSP and, there ore, are well visualized in a 45-degree oblique position. Apophyseal joints are ormed by articulating sur aces o the in erior articular acet o one vertebra with the superior articular acet o the vertebra below; they are well demonstrated in the lateral position o the cervical spine. T e intervertebral disk spaces are best demonstrated in the lateral position.

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26. (B) SNR can re er to home television images, magnetic resonance images (MRIs), ultrasound images, x-ray images, and so on. Noise inter eres with visualization o image details, or example, scattered radiation og, graininess rom quantum mottle, and so on. T e actual signal can be rom x-rays, sound waves, and so on. T e signal is desirable, the noise is not, there ore, a higher SNR produces a higher-quality image. Low SNR severely impairs contrast resolution.

portion lies more anterior. Consequently, in the recumbent position, barium will gravitate to the undus when the patient is supine and to the pylorus when the patient is prone. Since the image shows a barium- lled undus, it must have been made in the AP projection or LPO position. A look at the vertebrae indicates that the body is somewhat obliqued, indicating an LPO position. Note the double-contrast demonstration o rugal olds in the body o the stomach and double-contrast delineation o the pylorus and duodenal bulb.

27. (C) As kilovoltage is increased, more electrons are driven to the anode with greater speed and energy. More high-energy electrons will result in production o more (i.e., increased exposure rate) high-energy (i.e., short-wavelength) x-rays. T us, peak kilovoltage a ects both quantity and quality o the x-ray beam. However, although peak kilovoltage and radiographic density are directly related, they are not directly proportional; that is, twice the radiographic density does not result rom doubling the kilovoltage. With respect to the e ect o peak kilovoltage on image density, there is a convenient rule (15% rule) that can be ollowed. I it is desired to double the radiographic density yet impossible to adjust the milliampere-seconds, a similar e ect can be achieved by increasing the kilovoltage by 15%. Conversely, the density may be cut in hal by decreasing the kilovoltage by 15%.

29. (A) Distortion is misrepresentation o the actual size or shape o the object being imaged. Size distortion is magni cation. Shape distortion is a result o improper alignment o the x-ray tube, the part being radiographed, and the IR; the two types o shape distortion are oreshortening and elongation. T e shapes o various structures can be misrepresented radiographically as a result o their position in the body, when the part is out o the central axis o the x-ray beam, or when the CR is angled (Fig. 6-19). Parts sometimes are elongated intentionally or better visualization (e.g., sigmoid colon). Some body parts, because o their position in the body, are oreshortened, such as the carpal scaphoid. Attenuation re ers to decreasing beam intensity and is unrelated to distortion.

28. (C) T e stomach is generally not parallel with the long axis o the body—its undus/superior portion lies more posterior, and the pylorus/in erior

CR

30. (D) Conventional 60-Hz ull-wave recti ed power is converted to a higher requency o 500 to 25,000 Hz

CR

Obje ct s ize /s ha pe

P roje cte d ima ge s ize /s ha pe

Figure 6-19.

Answers: 26–38

in the most recent generator design—the highrequency generator. T e high- requency generator is small in size, in addition to producing an almost constant potential wave orm. High- requency generators rst appeared in mobile x-ray units and were then adopted by mammography and C equipment. oday, more and more radiographic equipment uses high- requency generators. T eir compact size makes them popular, and the act that they produce nearly constant potential voltage helps to improve image quality and decrease patient dose ( ewer low-energy photons to contribute to skin dose) 31. (B) issue is most sensitive to radiation exposure when it is in an oxygenated condition. Anoxic re ers to a general lack o oxygen in tissue; hypoxic re ers to tissue with little oxygen. Anoxic and hypoxic tumors typically are avascular (with little or no blood supply) and, there ore, more radioresistant. 32. (B) Diagnostic imaging examinations must be scheduled appropriately. Retained barium sul ate contrast medium can obscure necessary anatomic details in x-ray or ultrasound studies that are scheduled later. T ere ore, the ultrasound examination should come rst, ollowed by the lower GI series (BE), and nally the upper GI series. Retained barium rom the lower GI series probably will not obscure upper GI structures. 33. (B) T e heart superimposes a homogeneous density over the sternum in the RAO position, thus providing clearer radiographic visualization o its bony structure. I the LAO position were used to project the sternum to the right o the thoracic vertebrae, the posterior ribs and pulmonary markings would cast con using shadows over the sternum because o their di ering densities. Prominent pulmonary markings can be obliterated using a “breathing technique,” that is, using an exposure time long enough (with appropriately low milliamperage) to equal at least a ew respirations. 34. (D) In electronic/digital imaging, changes in window width a ect changes in contrast scale, while changes in window level a ect changes in brightness (in analog terms, density). As window width decreases, the scale o contrast decreases (i.e., contrast increases). As window level decreases, brightness decreases. It should be noted that, to describe a

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decrease in brightness, our analog terminology would say that density increases. T is can be easily illustrated as you postprocess/window your personal digital photographs or scanned documents. As you slide the brightness scale to decrease brightness, the photo/image gets lighter/brighter, that is, density decreases. 35. (C) T e AP axial projection is used to avoid clavicle superimposition on the pulmonary apices. A 15- to 20-degree cephalad angle projects the clavicles above the apices. T e radiograph is evaluated or rotation by checking the distance between the medial ends o the clavicles and the lateral border o the vertebral column. 36. (B) Anaphylaxis is an acute reaction characterized by sudden onset o urticaria, respiratory distress, vascular collapse, or systemic shock; it sometimes leads to death. It is caused by ingestion or injection o a sensitizing agent such as a drug, vaccine, contrast agent, or ood or by an insect bite. Asthma and rhinitis are examples o allergic reactions. Myocardial in arction results rom a blocked coronary artery. 37. (A) One o the biggest advantages o CR/DR is the latitude it o ers. T e characteristic curve o typical lm emulsion has a “range o correct exposure” limited by the toe and shoulder o the curve. In CR/ DR, there is a linear relationship between the exposure given the PSP and its resulting luminescence as it is scanned by the laser, as illustrated in the gure shown. T is a ords much greater exposure latitude; technical inaccuracies can be e ectively eliminated. Overexposure o up to 500% and underexposure o up to 80% are reported as recoverable, thus eliminating most retakes. T is surely a ords increased e ciency; however, this does not mean that images can be exposed arbitrarily. T e pro essional radiographer has a responsibility to keep dose reduction to a minimum. T e same technical actors as screen– lm systems or less generally are recommended or CR/DR. 38. (B) Computed radiography (CR) o ers wide latitude and automatic optimization o the radiologic image. When AEC is not used, CR can compensate or about 80% underexposure and 500% overexposure. T is can be an important advantage in trauma and mobile radiography. T e radiographer still

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must be vigilant in patient dose considerations— overexposure, though correctable, results in increased patient dose. Underexposure results in decreased image quality owing to increased image noise. CR systems provide an exposure indicator: an S (sensitivity) number, exposure index EI, or other relative exposure index depending on the manu acturer used. T e manu acturer usually provides a chart identi ying the acceptable range the exposure indicator should be within or various examination types. For example, a high S number o en is related to underexposure, whereas a high EI number is related to overexposure. Field o view (FOV) re ers to the anatomic area being visualized. 39. (D) A PA projection o the le hand and wrist is obtained most o en to evaluate skeletal maturation. T ese images are compared with standard normal images or the age and sex o the child. Additional supplemental images may be requested.

0.5 rem). T is dose limit is the total or the entire gestational period. T e dose limit or 1 month during pregnancy is 0.5 mSv (50 mrem, 0.05 rem). 43. (B) Fluids and medications are administered to patients intravenously to achieve a more rapid response to the medication than i it were delivered orally or intramuscularly. T e IV route is also o en used to deliver parenteral nutrition to patients who cannot take their meals by mouth. Medications that are administered topically, such as calamine lotion, achieve a local e ect. 44. (D) Each o the three is included in a good QC program. Beam alignment must be accurate to 2% o the SID. Reproducibility means that repeated exposures at a given technique must provide consistent intensity. Linearity means that a given milliampere-seconds value, using di erent milliamperage stations with appropriate exposure-time adjustments, will provide consistent intensity.

40. (A) T e PSP storage plate within the IP has a layer o europium-activated barium uorohalide (BaFX: Eu 2+ ; X = halogen) mixed with a binder substance. T is layer serves as the image receptor when exposed in the traditional manner; it looks very much like an x-ray cassette intensi ying screen. T e barium uorohalide is usually granular or turbid phosphors. Other examples o turbid phosphors are gadolinium oxysul de and rubidium chloride. “Needle”-shaped, or columnar phosphors (usually, cesium iodide), have the advantage o better x-ray absorption and less light di usion. Just under the barium uorohalide layer is a ref ective layer that helps direct emitted light up toward the CR reader. Below the re ective layer is the base, behind that is an antistatic layer, and then the lead oil to absorb backscatter. Over the top o the barium uorohalide is a protective layer.

45. (D) A distinction is made between the actual ocal spot and the e ective, or projected, ocal spot. T e actual ocal spot is the nite area on the tungsten target that is actually bombarded by electrons rom the lament. T e e ective ocal spot is the oreshortened size o the ocus as it is projected down toward the image receptor. T is is called line ocusing or the line- ocus principle. T e quoted ocal-spot size is the e ective ocal-spot size.

41. (D) Body substance precaution procedures identi y various body uids as in ectious or potentially in ectious. T ese body substances include pleural, pericardial, peritoneal, and amniotic uids; synovial uid; CSF; breast milk; and vaginal secretions, as well as semen, nasal secretions, tears, saliva, sputum, eces, urine, and wound drainage.

47. (A) An analgesic is any drug, such as aspirin, which unctions to relieve pain. An anticoagulant (e.g., heparin) is used to prevent clotting o blood. A diuretic is used to increase urine output. And an antibiotic (e.g., penicillin) ghts the growth o bacterial microorganisms.

42. (B) T e NCRP recommends a total equivalent dose limit to the embryo/ etus o 5 mSv (500 mrem,

46. (B) T e image shown is an erect PA projection o a patient o hyposthenic body habitus. Note the low position o the gallbladder. It is a result o body habitus and position (viscera assume a lower position in the erect position). T e gallbladder may be moved away rom the spine by using the LAO position. T e right lateral decubitus position also will move the gallbladder away rom the spine.

48. (B) T ere are several radiation units that are used to express quantity and e ects o radiation. Radiation ionizes air, and the unit o measurement used

Answers: 39–55

to describe the amount o ionization (and, thereore, the quantity o radiation present) is the roentgen. T e rad is the unit o absorbed dose. T e rem is the unit o dose equivalent, which expresses radiation dose to biologic material. 49. (D) T e computed radiography (CR) laser scanner recognizes the various tissue-density values and constructs a representative grayscale histogram. A histogram is a graphic representation showing the distribution o pixel values. Histogram analysis and use o the appropriate LU together unction to produce predictable image quality in CR. Histogram appearance can be a ected by a number o things. Degree o accuracy in positioning and centering can have a signi cant e ect on histogram appearance (as well as patient dose). Change is e ected in average exposure level and exposure latitude; these changes will be re ected in the images in ormational numbers (i.e., S number and exposure index). Other actors a ecting histogram appearance, and there ore these in ormational numbers, include selection o the correct processing algorithm (e.g., chest vs. emur vs. cervical spine) and changes in scatter, SID, OID, and collimation. Figure 6-20 illustrates the e ect o incorrect collimation on histogram appearance—in short, anything that a ects scatter and/or dose.

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treatments or osteoporosis. It is the most widely used method o bone densitometry—it is low dose, precise, and uncomplicated to use/ per orm. DXA uses two photon energies—one or so tissue and one or bone. Since bone is denser and attenuates x-ray photons more readily, the attenuation is calculated to represent the degree o bone density. So tissue attenuation in ormation is not used to measure bone density. 51. (D) Vector, omite, and airborne are all indirect modes o transmitting microorganisms. Direct contact involves actual touching o the in ected person. A omite is an inanimate object that has been in contact with an in ectious microorganism (e.g., doorknobs or x-ray tables). Although an inanimate object may serve as a temporary host or microbes, microbes ourish on and in the human host, where plenty o body uids and tissues nourish and eed them. A vector is an animal host o an in ectious organism that transmits the in ection via a bite or sting, such as the mosquito or deer tick. Airborne contamination occurs via droplets (sneeze) or dust. 52. (C) I 0.8 rad were delivered in 4 minutes, then the dose rate would be 0.8/4, or 0.2 rad/min. T us, 0.2 rad is equal to 200 mrad. 53. (A) As kilovoltage is increased, more electrons are driven to the anode with greater speed and energy. T ese high-energy electrons will result in production o a greater quantity (i.e., increased exposure rate/intensity) o high-energy (i.e., short/decreased wavelength) x-rays. T us, kilovoltage a ects both quantity and quality o the x-ray beam.

Properly collimated

Noncollimated beam

Normal histogram

Wider histogram

Figure 6-20. Courtesy FUJIFILM Medical Systems USA, Inc.

50. (B) Dual x-ray absorptiometry (DXA) imaging is used to evaluate bone mineral density (BMD). Bone densitometry/DXA can be used to evaluate bone mineral content o the body, or part o it, to diagnose osteoporosis, or to evaluate the e ectiveness o

54. (C) T e medial oblique projection o the ankle can be per ormed either as a 15- to 20-degree oblique or as a 45-degree oblique. T e 15- to 20-degree oblique projection demonstrates the tibio bular articulation and the entire ankle mortise, that is, the articulations between the talus, tibia, and bula. T e 45-degree oblique opens the distal tibio bular joint. Additionally, as degree o rotation increases, the space between the tibia and bula increases. In all three cases, although the MSP/ rotation can change, the plantar sur ace must be perpendicular to the lower leg. 55. (D) A point lesion is a disturbance o a single chemical bond that can result in mal unction

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within the a ected cell. Following irradiation, a small extension-type molecule can develop, extending rom the main chain. T is molecule can attach to a neighboring molecule or to another portion o the same molecule; this is re erred to as cross-linking. Main-chain scission is breakage o the molecule’s principal connection so that the molecule is broken into smaller molecules. Each o these radiation e ects on macromolecules is repairable. 56. (C) T e human body is composed o approximately 80% water; the remaining 20% is a combination o substances such as proteins, carbohydrates, and lipids. T e smallest unctional unit o the body is the cell; the structure/content o a cell o en determines its unction. Cells orm tissues and organs that also have unctional characteristics. T e two basic types o cells are somatic and genetic. Somatic cells are all the body’s cells (bone, muscle, nerve, etc.), except those concerned with reproduction—those cells are termed genetic. 57. (A) A vector is an animal host o an in ectious organism that transmits the in ection via a bite or sting, such as the mosquito (malaria) and the deer tick (Lyme disease). A omite is an inanimate object that has been in contact with an in ectious microorganism. A reservoir is a site where an in ectious organism can remain alive and rom which transmission can occur. Although an inanimate object can be a reservoir or in ection, living objects (such as humans) can also be reservoirs. For in ection to spread, there must be a host environment. Although an inanimate object may serve as a temporary host or microbes to grow, microbes ourish on and in the human host, where plenty o body uids and tissue nourish and eed the microbes. 58. (A) T e relationship between x-ray intensity and distance rom the source is expressed in the inverse-square law o radiation. T e ormula is I1 D22 = 2 I2 D1 Substituting known values: 18 25 = x 4 2.5x = 72 T us, x = 2.88 mR/min at 5 m. Distance has a proound e ect on dose received and, there ore, is one

o the cardinal actors considered in radiation protection. As distance rom the source increases, dose received decreases. 59. (D) Fluoroscopy is a potentially higher patient dose procedure. T e principal reason or this is that the source o x-ray photons is in closer proximity to the patient than in overhead imaging. T ere are NCRP recommendations that provide guidelines or minimum source-to-skin distance (SSD), maximum tube output, collimation, timer and exposure switch speci cations, etc. An advantage o digital uoroscopy is reduced patient dose. T e principal reason or lower patient dose in DF is that DF x-ray beams are pulsed, rather than continuous. In addition, the V camera tube or CCD has greater sensitivity than does the lm emulsion used in analog (screen/ lm) imaging. Ways to Decrease Patient Fluoroscopic Dose • Decrease length o uoroscopic exposure/procedure • Employ use o last image hold • Keep patient as close to the Image Intensif er (II) as possible • Use Automatic Brightness Control (ABC) setting with highest kV/lowest mA combination • Minimize use o “boost”and “magnif cation”modes • Collimation; use smallest Field o View (FOV) • Use lowest practical pulse rate • Change tube angle or patient position to spread dose over larger area

60. (B) With the patient in the AP position, the CR is directed cephalad 25 to 30 degrees. T is serves to project the clavicle away rom the pulmonary apices and ribs, projecting most o the clavicle above the thorax. T e reverse is true when the patient is examined in the PA position. T e PA projection can be use ul to obtain better recorded detail because o reduced OID. 61. (C) Receptor exposure is directly proportional to milliampere-seconds. I exposure time is halved rom 0.04 s to 0.02 s, receptor exposure will be cut in hal . Changing to 300 mA also will halve the milliampere-seconds, e ectively halving the receptor exposure. I the kilovoltage is decreased by 15%, rom 85 to 72 kVp, receptor exposure will be halved according to the 15% rule. o cut the receptor exposure in hal , the milliampere-seconds must be reduced to 12 mAs (rather than to 18 mAs). 62. (B) Proper body mechanics can help to prevent pain ul back injuries by making pro cient use o

Answers: 56–72

the muscles in the arms and legs. Proper body mechanics includes a wide base o support. T e base o support is the part o the body in touch with the oor or other horizontal plane. T e back always should be kept straight; twisting increases the chance o injury. When li ing a load, keep it as close to the body as possible to avoid back strain. Always push a load (such as a mobile x-ray machine) rather than pull it. 63. (A) In the AP projection o the normal knee, the space between the tibial plateau and the emoral condyles is equal bilaterally. It is, there ore, important that there be no pelvic rotation that could change the appearance o an otherwise normal relationship. T e AP projection o the knee superimposes the patella and emur. T e CR should enter at the knee joint, located 1⁄2 in distal to the patellar apex. 64. (A) Lead and distance are the two most important ways to protect rom radiation exposure. Fluoroscopy can be particularly hazardous because the SID is so much shorter than in overhead radiography. T ere ore, it has been established that mobile uoroscopic equipment must provide at least 12 in source-to-tabletop/skin distance or the protection o the patient, and xed or stationary uoroscopic equipment must provide at least 15 in source-totabletop/skin distance. 65. (C) T e trachea (windpipe) bi urcates into le and right main stem bronchi, each o which enters its respective lung hilum. T e le bronchus divides into two portions—one or each lobe o the le lung. T e right bronchus divides into three portions—one or each lobe o the right lung. T e lungs are conical in shape, consisting o upper pointed portions, termed the apices (plural o apex), and broad lower portions (or bases). T e lungs are enclosed in a double-walled serous membrane called the pleura. 66. (B) An arti act associated with digital imaging and grids is “aliasing” or the “Moiré e ect.” I the direction o the lead strips and the grid lines per inch (i.e., grid requency) matches the scan requency o the scanner/reader, this arti act can occur. Aliasing (or Moiré e ect) appears as superimposed images slightly out o alignment, an image “wrapping” e ect. T is most commonly occurs in

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mobile radiography with stationary grids and can be a problem with DR at panel detectors. 67. (C) Arthrodesis, or spinal usion, is a surgical procedure that might be employed in cases o certain ractures, degenerative disc disease, spinal stenosis, degenerative spondylolisthesis, and other vertebral conditions. It is most o en seen in the lumbar region. Implants might be employed to hold vertebrae in position/alignment. A er approximately 6 months post surgery imaging is o en help ul in demonstrating the degree o motion permitted at the site(s) o usion. T e images can include AP le and right bending to demonstrate degree o lateral motion, and lateral in exion and extension to demonstrate degree o AP motion. 68. (B) T e bony walls o the orbit are thin, ragile, and subject to racture. A direct blow to the eye results in a pressure that can cause racture. T at racture is usually to the orbital oor (the in erior aspect o the bony orbit). Because the racture results rom increased pressure within the eye, it is re erred to as a blowout racture. 69–70. (69, A; 70, C) T e gure shows a posterior view o the elbow. T e distal posterior humerus (number 1) is seen, as well as the proximal posterior radius (number 4) and ulna (number 3). Additional structures identi ed are the medial epicondyle (number 2), the olecranon ossa (number 5), olecranon process (number 6), lateral epicondyle (number 7), and radial head (number 8) T e olecranon process (number 6) can best be demonstrated in the lateral projection; it can also be demonstrated in the acute exion position. T e AP internal oblique will demonstrate the coronoid process; the AP external oblique will demonstrate the radial head ree o superimposition. 71. (C) Emphysema is a progressive disorder caused by long-term irritation o the bronchial passages, such as by air pollution or cigarette smoking. Emphysema patients are unable to exhale normally because o the loss o elasticity o the alveolar walls. I emphysema patients receive oxygen, it is usually administered at a very slow rate because their respirations are controlled by the level o carbon dioxide in the blood. 72. (D) T e x-ray anode may be a molybdenum disk coated with a tungsten–rhenium alloy. ungsten,

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with a high atomic number (74), produces highenergy x-rays quite ef ciently. Since a great deal o heat is produced at the target, its high melting point (3,410°C) helps to avoid damage to the target sur ace. Heat produced at the target should be dissipated readily, and tungsten’s conductivity is similar to that o copper. T ere ore, as heat is applied to the ocus, it can be conducted throughout the disk to equalize the temperature and thus avoid pitting, or localized melting, o the ocal track. 73. (A) T e diameter o a needle is the needle’s gauge. T e higher the gauge number, the thinner is the diameter. For example, a very tiny-gauge needle such as 25-gauge needle may be used on a pediatric patient or IV injection, whereas a large-gauge needle such as 16-gauge needle may be used or donating blood. T e hub o the needle is the portion o the needle that attaches to a syringe. T e length o the needle varies depending on its use. A longer needle is needed or intramuscular injections; a shorter needle, or a subcutaneous injection. T e bevel o the needle is the slanted tip o the needle. For IV injections, the bevel should always ace up. 74. (C) X-ray tube li e may be extended by using technical actors that produce a minimum o heat, that is, a lower milliampere-seconds and higher kilovoltage combination, whenever possible. When the rotor is activated, the lament current is increased to produce the required electron source (thermionic emission). Prolonged rotor time, then, can lead to shortened lament li e as a result o early vaporization. Large exposures to a cold anode will heat the anode sur ace, and the big temperature di erence can cause cracking o the anode. T is can be avoided by proper warming o the anode prior to use, thereby allowing suf cient dispersion o heat through the anode. 75. (D) Gonadal shielding should be used when the gonads lie within 5 cm o the collimated primary beam, when the patient has reasonable reproductive potential, and when clinical objectives permit. Because their reproductive organs lie outside the abdominal cavity, male patients are more easily and e ectively shielded than are emale patients, whose reproductive organs lie within the abdominal cavity. T ere ore, radiographic examinations o the male abdomen and pelvic structures should include evidence o gonadal shielding.

76. (D) A parallel-plate ionization chamber is a type o automatic exposure control (AEC). A radiolucent chamber is beneath the patient (between the part and the IR). As photons emerge rom the part, they enter the chamber and ionize the air within it. Once a predetermined charge has been reached, the exposure is terminated automatically. A phototimer is another type o AEC that actually measures light. As x-ray photons penetrate and emerge rom a part, a uorescent screen beneath the IR glows, and the uorescent light charges a photomultiplier tube. Once a predetermined charge has been reached, the exposure terminates automatically. An induction motor is used to rotate the anode o the x-ray tube. An autotrans ormer operates on the principle o sel -induction and is use ul in kV selection. 77. (C) T e image illustrates an oblique view o the proximal radius and ulna and distal humerus with epicondyles 45 degrees to the IR—the external oblique (lateral rotation) projection is shown demonstrating the radial head ree o superimposition as well as the radial neck, tuberosity, and the humeral capitulum. T e medial oblique (internal rotation) projection o the elbow is particularly use ul to demonstrate the coronoid process in pro le, the trochlea, and the medial epicondyle. T e acute exion projection (Jones method) o the elbow is a two-projection method demonstrating the elbow anatomy when the part cannot be extended or an AP projection. 78. (B) T e emale pelvis di ers rom the male pelvis in that it is shallower and its bones generally are lighter and more delicate (Figure 6-21). T e pelvic outlet is wider and more circular in the emale, and the ischial tuberosities and acetabula are arther apart; the angle ormed by the pubic arch is also greater (more than 100 degrees) in the emale. All these bony characteristics acilitate childbearing and birth. 79. (B) T e photoelectric e ect and Compton scattering are the two predominant interactions between x-ray photons and matter in diagnostic x-ray. In Compton scatter, the high-energy incident photon uses only part o its energy to eject an outer-shell electron. It retains most o its original energy in the orm o a scattered x-ray. T e outer-shell electron leaves the atom and is called a recoil electron.

Answers: 73–85

90 de gre e or le s s A

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100 de gre e or more

B

Figure 6-21.

Compton scatter is the interaction between x-ray photons and matter that occurs most requently in diagnostic x-ray and is the major contributor o scattered radiation og. In the photoelectric e ect, the low-energy incident photon uses all its energy to eject an atom’s inner-shell electron. When photon ceases to exist, it means it has used all its energy to ionize the atom. T e part has absorbed the x-ray photon. T is interaction contributes to patient dose and produces short-scale contrast. 80. (B) As the exposed lm enters the processor rom the eed tray, it rst enters the developer section (number 1), where the emulsion’s exposed silver halide grains are reduced to black metallic silver. T e lm then enters the xer (number 2), where the unexposed silver grains are removed rom the lm by the clearing agent (hypo). T e lm then enters the wash section (number 3), where chemicals are removed rom the lm to preserve the image. From the wash section, the lm enters the dryer section (number 4). 81. (B) It is the radiographer’s responsibility to keep radiation exposure to patients and to himsel or hersel to a minimum. T e embryo/ etus is particularly radiosensitive. One way to avoid irradiating a newly ertilized ovum is to inquire about the possibility o a emale patient being pregnant or to ask her or the date o her last menstrual period. T e sa est time or a woman o childbearing age to have elective radiographic examinations is during the rst 10 days ollowing the onset o menstruation.

82. (D) Geometric unsharpness is a ected by all three actors listed. As OID increases, so does magni cation. As ocal-object distance and SID decrease, so does magni cation. OID may be said to be directly proportional to magni cation. Focal-object distance and SID are inversely proportional to magni cation. 83. (C) T e x-ray tube’s glass envelope and oil coolant are considered inherent (built-in) ltration. T in sheets o aluminum are added to make a total o at least 2.5-mm Al equivalent ltration in equipment operated above 70 kVp. T e unction o the ltration is to remove the low-energy photons that serve only to contribute to skin dose. 84. (C) T e quantity o radiation absorbed by the skin rom the primary beam is re erred to as the ESE. Although the primary x-ray beam is ltered, it is still quite heterogeneous, containing x-ray photons o low energy that do not contribute to image ormation but do contribute to patient skin dose. T us, the greater the intensity o the initial primary beam, the greater the ESE will be. T ere ore, the chest delivers the lowest ESE (12–26 mR); the next is the skull (105–240 mR), then the thoracic spine (290–485 mR), and the examination delivering the greatest ESE is the abdomen (375–698 mR). 85. (C) A number o milliamperage and exposure time settings can produce the same milliampere-seconds (mAs) value. Each o the ollowing milliamperage and time combinations produces 10 mAs: 100 mA

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and 0.1 s, 200 mA and 0.05 s, 300 mA and, and 400 mA and 0.025 s. T ese milliamperage and exposure-time combinations should produce identical receptor exposure. T is is known as the reciprocity law. T e radiographer can make good use o the reciprocity law when manipulating technical actors to decrease exposure time and decrease motion unsharpness.

during IVU to visualize them better. With the AP oblique projections (i.e., RPO and LPO), the kidney that is arther away is placed parallel to the IR, and the kidney that is closer is placed perpendicular to the IR. T ere ore, in the RPO position, the right kidney, being closer, is perpendicular to the IR. T e le kidney, the one arther away, is placed parallel to the IR.

86. (B) Abduction o the arm o the a ected side serves to ree the scapula o some o its superimposition on the ribs. T e a ected arm should be perpendicular to the long axis o the body, with the elbow exed and hand supported. T e thorax should not be rotated toward the a ected side, as that would de eat the purpose o arm abduction and move the ribs over the scapula. T e CR should be directed to the mid-scapula, approximately 2 in in erior to the coracoid process.

90. (B) Carpal tunnel syndrome involves pain and numbness to some parts o the median nerve distribution (i.e., palmar sur ace o the thumb, index nger, and radial hal o the ourth nger and palm). Carpal tunnel syndrome occurs requently in those who continually use vibrating tools or machinery. Carpopedal spasm is spasm o the hands and eet, commonly encountered during hyperventilation. Carpal boss is a bony growth on the dorsal sur ace o the third metacarpophalangeal joint.

87. (B) When the hand is pronated and the ngers are extended or a PA projection o the wrist, the wrist arches, and an OID is introduced between the wrist and the cassette. o reduce this OID, the metacarpophalangeal joints should be exed slightly. T is maneuver will bring the anterior sur ace o the wrist into contact with the cassette.

91. (B) As eld size decreases, the volume o tissue being irradiated decreases, and consequently, the production o scattered radiation decreases. Less scattered radiation production results in decrease receptor exposure. Restriction o eld size is an important way to reduce patient dose and improve image quality. Field size and scattered radiation are unrelated to resolution.

88. (C) Quality Control re ers to our equipment and its sa e and accurate operation. Various components must be tested at speci ed intervals and test results must be within speci ed parameters. Any deviation rom those parameters must be corrected. Examples o equipment components that are tested annually are the ocal-spot size, linearity, reproducibility, ltration, kV, and exposure time. Congruence is a term used to describe the relationship between the collimator light eld and the actual x-ray eld—they must be congruent (i.e., match) to within 2% o the SID. Radiographic equipment collimators should be inspected and veri ed as accurate semiannually, that is, twice a year. Kilovoltage settings can most e ectively be tested using an electronic kV meter; to meet required standards, the kV should be accurate to within + /–4 kV. Reproducibility testing should speci y that radiation output be consistent to within + /–5%. 89. (D) Since the kidneys do not lie parallel to the IR in the AP position, the oblique positions are used

92. (B) Computer hardware describes the actual computer equipment (CPU, keyboard, memory chips, etc.). T e so ware are the computer programs— algorithms, or programmed instructions, that are needed to per orm speci c tasks. A modem converts a computer’s outgoing digital signal to an analog signal, which is then transmitted via telephone line to another computer where it must rst be changed back to a digital signal or computer processing. A histogram is a graphic representation o pixel value distribution. T e histogram is an analysis and graphic representation o all the densities rom the PSP screen, demonstrating the quantity o exposure, the number o pixels, and their value. 93. (B) T e legal doctrine res ipsa loquitur relates to “a matter that speaks or itsel .” For instance, i a patient were admitted to the hospital to have a kidney stone removed and incorrectly was given an appendectomy, “that speaks or itsel ,” and

Answers: 86–100

negligence could be proven. Respondeat superior is the phrase meaning “let the master answer” or “the one ruling is responsible.” I a radiographer is negligent, there may be an attempt to prove that the radiologist was responsible because the radiologist oversees the radiographer. Res judicata means “a thing or matter settled by justice.” Stare decisis re ers to “a matter settled by precedent.” 94. (D) OID is used to e ect an increase in contrast in the absence o a grid, usually in chest radiography. I a 6-in air gap (OID) is introduced between the part and the IR, much o the scattered radiation emitted rom the body will not reach the IR; thus, the OID acts as a low-ratio grid and increases image contrast. However, the 6-in OID air gap will make a very noticeable increase in magni cation. o correct this, the SID must be increased. Generally speaking, the SID needs to be increased 7 in or every 1 in o OID. With a 6-in OID, the SID usually is increased rom 6 to 10 (120 in). 95. (D) In the AP projection o the knee, the position o the joint space is signi cantly a ected by the patient’s overall body habitus and the distance between the ASIS and tabletop. When the patient is o sthenic habitus with a distance o 19 to 24 cm between the ASIS and tabletop, the CR is directed perpendicularly. When the patient is o asthenic habitus with a distance o less than 19 cm between the ASIS and tabletop, the CR is directed 5 degrees caudad. With a patient with a hypersthenic habitus and an ASIS-to-table measurement o greater than 24 cm, the CR is directed 5 degrees cephalad. 96. (C) T e radiograph shows evidence o very ew grays; this is short scale, or high, contrast. T ere is inadequate penetration o the high tissue density structures—the heart and the lung bases and apices. Penetration is a unction o kilovoltage; inadequate penetration is a result o kilovoltage. In SF/analog imaging, contrast is regulated by kV. In digital imaging, contrast is regulated by computer so ware and is unrelated to kV. 97. (A) Remnant x-rays emerging rom the patient/ part are converted to electrical signals. T is is an analog image. T ese electrical signals are sent to the ADC (analog-to-digital converter) to be converted to digital data (in binary digits or bits). T en

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the digital image data is trans erred to a DAC (digital-to-analog converter) to be converted to a perceptible analog image on the display monitor. T e monitor image can be manipulated, postprocessed, stored, or transmitted. 98. (C) Kilovoltage (kVp) and hal -value layer (HVL) change both the quantity and the quality o the primary beam. T e principal qualitative actor o the primary beam is peak kilovoltage, but an increase in kilovoltage will also a ect an increase in the number o photons produced at the target. HVL is de ned as the amount o material necessary to decrease the intensity o the beam to one-hal its original value, thereby e ecting a change in both beam quality and quantity. T e milliampere-seconds value is adjusted to regulate the number o x-ray photons produced at the target. X-ray beam quality is una ected by changes in milliampere-seconds. 99. (A) T e abdomen is divided anatomically into nine regions and our quadrants. T e region designation usually is used or anatomic studies, whereas the quadrant designation is used most o en to describe the location o a lesion, pain, tumor, or other abnormality. Some o the structures ound in the le upper quadrant (LUQ) are the undus o the stomach, the le kidney and suprarenal gland, and the splenic exure. 100. (D) For negligent tort liability, our elements must be present—duty (what should have been done), breach (deviation rom duty), injury sustained, and cause (as a result o breach). T e assessment o duty is determined by the pro essional standard o care. Examples o negligent torts include patient injury as a result o a all while unattended on an x-ray table, in a radiographic room, or on a stretcher without side rails or sa ety belt. Radiographing the wrong patient and radiographing the opposite limb are other examples o negligence. I patient injury results rom misper ormance o a duty in the routine scope o practice o the radiographer, most courts will apply res ipsa loquitur; that is, “the thing speaks or itsel .” I the patient is obviously injured as a result o the radiographer’s actions, it becomes the radiographer’s burden to disprove negligence. In many instances, the hospital and/or radiologist also will be held responsible according to respondeat superior, or “the master speaks or the servant.”

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101. (B) o change nongrid to grid exposure, or to adjust exposure when changing rom one grid ratio to another, recall the actor or each grid ratio: No grid = 5:1 grid = 6:1 grid = 8:1 grid = 12:1 grid = 16:1 grid =

1× 2× 3× 4× 5× 6×

original mAs original mAs original mAs original mAs original mAs original mAs

T e grid conversion ormula is mAs1 grid factor1 = mAs2 grid factor2 Substituting known quantities: 6 3 = x 5 3x = 30 T us, x = 10 mAs with a 12:1 grid. 102. (C) Hypoglycemic reactions can be very severe and should be treated with an immediate dose o sugar in the orm o juice or candy. Symptoms o hypoglycemia include atigue, restlessness, irritability, and weakness. Diabetic patients who have not taken their insulin prior to a asting examination should be given priority, and their examinations should be expedited as quickly as possible. 103. (A) T e intertubercular (bicipital) groove is located on the proximal humerus, distal to the head, between the greater and lesser tubercles. T e distal humerus articulates with the radius and ulna to orm the elbow joint. T e lateral aspect o the distal humerus presents a raised, smooth, rounded sur ace, the capitulum, which articulates with the superior sur ace o the radial head. T e trochlea is on the medial aspect o the humerus and articulates with the semilunar notch o the ulna. Just proximal to the capitulum and the trochlea are the lateral and medial epicondyles; the medial is more prominent and palpable. T e coronoid ossa is ound on the anterior distal humerus and unctions to accommodate the coronoid process with the elbow in exion. 104. (B) T e posterior oblique positions (LPO, RPO) are used to demonstrate the apophyseal articulations o L1 through L4. When correctly positioned, the classic “Scottie Dog” would be visualized. I the

apophyseal articulations are not “open,” that is, clearly visualized, and the pedicle is seen on the posterior aspect o the vertebral body, patient rotation should be decreased. I the apophyseal articulations are not clearly visualized, and the pedicle is seen on the anterior aspect o the vertebral body, patient rotation should be increased. 105. (D) T e input phosphor o image intensi ers is usually made o cesium iodide. For each x-ray photon absorbed by cesium iodide, approximately 5,000 light photons are emitted. As the light photons strike a photoemissive photocathode, a number o electrons are released rom the photocathode and ocused toward the output side o the image tube by voltage applied to the negatively charged electrostatic ocusing lenses. T e electrons are then accelerated through the neck o the tube, where they strike the small (0.5–1 in) output phosphor that is mounted on a at glass support. T e entire assembly is enclosed within a 2- to 4-mm thick vacuum glass envelope. Remember that the image on the output phosphor is mini ed, brighter, and inverted (electron ocusing causes image inversion). Input screen diameters o 5 to 12 in are available. Although smaller diameter input screens improve resolution, they do not permit a large FOV, that is, viewing o large patient areas. Dual- and triple- eld image intensi ers are available that permit magni ed viewing o uoroscopic images. o achieve magni cation, the voltage to the ocusing lenses is increased and a smaller portion o the input phosphor is used, thereby resulting in a smaller FOV. Because minication gain is now decreased, the image is not as bright. T e mA is automatically increased to compensate or the loss in brightness when the image intensi er is switched to magni cation mode. Entrance skin exposure (ESE) can increase dramatically as the FOV decreases (i.e., as magni cation increases). As FOV decreases, magni cation o the output screen image increases, there is less noise because increased mA provides a greater number o x-ray photons, and contrast and resolution improve. T e ocal point in the magni cation mode is urther away rom the output phosphor (as a result o increased voltage applied to the ocusing lenses) and there ore the output image is magni ed.

Answers: 101–113

106. (C) A controlled area is one that is occupied by radiation workers; the exposure rate in a controlled area must not exceed 100 mR/week. An uncontrolled area is one that is occupied by the general population; the exposure rate must not exceed 10 mR/ week. Shielding requirements vary according to several actors, one o them being occupancy actor. 107. (D) T e SF/analog milliampere-seconds value used was 8 (400 mA × 0.02 s); the new milliampere-seconds value is hal that – 4 mAs – which will result in hal the original receptor exposure. An increase in SID, as suggested by choice (A), would urther decrease receptor exposure. T e decrease in milliampere-seconds could be compensated or by a decrease in SID—but according to the exposure-maintenance ormula, that distance should be 28 inches. Decreasing the kilovoltage to 60 would also decrease the receptor exposure by another hal . Increasing the kilovoltage by 15%, as suggested by choice (D), will best simulate the original receptor exposure. 108. (B) Radiograph A was per ormed PA, and radiograph B per ormed AP, as evidenced by the bony pelvis anatomy. T e PA projection (image A) shows the ilia more oreshortened, giving the pelvis a “closed” appearance, whereas in the AP projection the ilia and bladder area appears more “open.” T ere was an appropriate selection o technical actors, or the required anatomic structures are well visualized—renal shadows, psoas muscle, lumbar transverse processes, and in erior margin o the liver. 109. (C) As radiation passes through tissue, di erent types o ionization processes can take place depending on the photon energy and the type o material being irradiated. T e photoelectric e ect (whose end products include a characteristic ray) and Compton scatter are the two major interactions that take place in the diagnostic x-ray peak kilovoltage range. T e rate at which energy is deposited in (or trans erred to) tissue during these interactions is termed linear energy trans er (LE ). T e greater the LE , the greater is the potential biologic e ect. Diagnostic x-ray is considered lowLE radiation. 110. (C) T e radiograph illustrates a plantodorsal projection o the calcaneus. T e patient usually is positioned with the leg extended and the long axis o

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the plantar sur ace perpendicular to the tabletop/ IR. T e CR is directed 40 degrees cephalad to the base o the third metatarsal. Structures that should be visualized include the sustentaculum tali, trochlear process, and calcaneal tuberosity. 111. (A) As radiation passes through tissue, di erent types o ionization processes can take place depending on the photon energy and the type o material being irradiated. In the photoelectric e ect, a relatively low-energy photon uses all its energy to eject an inner-shell electron rom the target atom, leaving a vacancy in that shell. An electron rom the shell beyond drops down to ll the vacancy and in so doing emits a characteristic ray. T is type o interaction contributes most to patient dose because all the x-ray photon energy is being transerred to tissue. In Compton scatter, a high–energy-incident photon uses some o its energy to eject an outer-shell electron. In so doing the incident photon is de ected with reduced energy but usually retains most o its original energy and exits the body as an energetic scattered photon. In Compton scatter, the scattered radiation will either contribute to image og or pose a radiation hazard to personnel depending on its direction o exit. In classic scatter, a low-energy photon interacts with an atom but causes no ionization; the incident photon disappears in the atom and then immediately reappears and is released as a photon o identical energy but with changed direction. T ompson scatter is another name or classic scatter. 112. (B) Image quality is evaluated according to image brightness, gray scale, spatial resolution, and distortion. T e visibility actors are brightness and gray scale, while the geometric actors are spatial resolution and distortion. T e technical actors we use to create the image are milliamperage (mA), exposure time (s), kilovoltage (kV), and SID. Patient variables that have signi cant impact on actor selection and the radiologic image include tissue density, tissue thickness, any pathology, and ability to communicate. 113. (D) T e thicker and more dense the anatomic part being studied, the less bright will be the uoroscopic image. Both milliamperage and kilovoltage a ect the uoroscopic image in a way similar to the way they a ect the radiographic image. For optimal contrast, especially taking patient dose into

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consideration, higher kilovoltage and lower milliamperage generally are pre erred.

gallbladder. T e asthenic colon is medial and redundant.

114. (B) T e absorption characteristics o the body tissues very considerably rom one section o the body to another. Some body tissues, such as the chest, possess high subject contrast, because o big di erences in (e.g., very dissimilar) absorption characteristics o adjacent tissues. Some body tissues possess low subject contrast, such as the abdomen. Adjacent tissues/organs o the abdomen have similar absorption characteristics. When di erences in absorption characteristics are minimal, body tissues absorb radiation more uniormly. In SF/analog imaging, this results in a longer scale o contrast. High kV (and low mAs) actors are used when adjacent tissues are very dissimilar, as in the thorax. T e high kV provides uni orm penetration, decreasing the signi cant di erential absorption o adjacent tissue structures. Compensating ltration is also used to “even out” tissue densities in uneven anatomic parts, such as the thoracic spine. T e photoelectric e ect is the interaction between x-ray photons and matter that occurs at low kV levels—levels that tend to produce less part penetration and short-scale contrast.

117–118. (117, C; 118, D) Diarthrotic joints, also described as synovial, are reely movable. T e majority o human articulations are the diarthrotic/synovial type, and there are several types o diarthrotic articulations. T e image shown is a PA projection o the hand and wrist; an oblique projection o the thumb is obtained. T e letter is pointing out the rst carpometacarpal joint, ormed by the base o the rst metacarpal and the trapezium. T is is classi ed as a sellar or saddle joint. T e sellar articulation permits exion, extension, adduction, adduction, and circumduction (no rotation). T e letter S is pointing out the second metacarpophalangeal joint, which is classi ed as ellipsoid or condyloid. Ellipsoid articulations permit exion, extension, abduction, adduction, and circumduction (no axial movement). Another example o an ellipsoid articulation is the radiocarpal joint.

115. (A) T e line- ocus principle is a geometric principle illustrating that the actual ocal spot is larger than the e ective (projected) ocal spot. T e actual ocal spot (target) is larger, to accommodate heat over a larger area, and angled so as to project a smaller ocal spot, thus maintaining recorded detail by reducing blur. T e relationship between distance and exposure rate is expressed in the inverse-square law. T e relationship between the kilovoltage and beam quality/penetration may be illustrated using an aluminum step wedge. 116. (B) T e our types o body habitus describe di erences in visceral shape, position, tone, and motility. One body type is hypersthenic, the very large individual with short, wide heart and lungs, high transverse stomach and gallbladder, and peripheral colon. T e sthenic individual is the average, athletic, most predominant type. T e hyposthenic patient is somewhat thinner and a little more rail, with organs positioned somewhat lower. T e asthenic type is smaller in the extreme, with a long thorax, a very long, almost pelvic stomach, and a low medial

119. (D) T e cervical intervertebral oramina lie 45 degrees to the midsagittal plane (MSP) and 15 to 20 degrees to the transverse plane. When the anterior oblique position (i.e., LAO or RAO) is used, the CR is directed 15 to 20 degrees caudad, and the oramina disclosed are those closer to the IR. When the posterior oblique position (i.e., LPO or RPO) is used, the CR is directed 15 to 20 degrees cephalad, and the cervical intervertebral oramina demonstrated are those arther rom the IR. T ere is, there ore, some magni cation o the oramina (because o the OID) in the posterior oblique positions. 120. (A) X-ray lm is sensitive and requires proper handling and storage. Careless handling during production o the radiographic image can produce several kinds o arti acts. Crescent-shaped artiacts (crinkle marks) are a result o bending the lm acutely over the ngertip while loading or unloading the cassette. A black crescent usually results rom bending a er exposure, whereas a white crescent occurs i the lm is bent be ore exposure. reelike branching black marks on a radiograph are usually due to static electrical discharge. Problems with static electricity are especially prevalent during cold, dry weather and can be produced simply by removing a sweater in the darkroom.

Answers: 114–130

121. (B) T e technical actor that regulates radiographic density is milliampere-seconds (mAs). T e equation used to determine mAs is mA × s = mAs. Substituting known actors: 300x = 18 mAs x = 0.06 s(60ms) 122. (A) I the photocell were centered more posteriorly to a thinner and less dense structure, then the exposure received would be correct or that lessdense structure. T e spinous processes would be well visualized, but the denser vertebral bodies and surrounding structures (pedicles and lamina) would be underexposed. Accurate selection o photocells and precise positioning are critical with the use o automatic exposure devices. 123. (A) Septic shock can result when the body is invaded by bacteria, in ection, or some type o toxin; there are o en accompanying signs o acute septicemia and hypotension. Septic shock can occur in individuals having weakened immune systems. Shock caused by an abnormally low volume o blood in the body is termed hypovolemic shock. Neurogenic shock can be caused by some kind o trauma to the nervous system, that is, spinal cord injury or extreme psychological stress. Cardiogenic shock is related to the heart and caused by ailure o the heart to pump adequate blood to the body’s vital organs. 124. (B) It is easy to determine the highest point o the scapula when it is viewed laterally. T e coracoid process projects anteriorly and is quite superior. However, the acromion process, which is an anterior extension o the scapular spine, projects considerably more superior than the coracoid. 125. (D) Base-plus og is the small amount o measurable density on unexposed and processed x-ray lm. T is og is a result o environmental background radiation that is present during lm manu acture, transportation, and storage. T e (usually blue) tint, given the base to enhance contrast, adds more density. Finally, the emulsion receives urther og as the lm is chemically processed. Base-plus og should not exceed 0.2D. 126. (B) Primary radiation barriers are barriers that protect rom the primary, or use ul, x-ray beam.

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Secondary radiation barriers are those that protect rom secondary or scattered radiation. Examples o primary barriers are the radiographic room walls, doors, and oors because the primary beam o en can be directed toward them. Secondary radiation barriers include lead aprons, gloves, thyroid shields, and the radiographic room ceiling. T ese will protect rom exposure to scattered radiation only. Secondary radiation barriers will not protect rom the use ul beam. 127. (A) T e gradual decrease in exposure rate as radiation passes through matter is called attenuation. Attenuation is attributed to the two major types o interactions that occur in tissue between x-ray photons and matter in the diagnostic x-ray range. In the photoelectric e ect, absorption and secondary radiation occur. In the Compton e ect, scattered radiation is produced. With each o these occurrences, there is a decrease in the exposure rate that is re erred to as attenuation. 128. (A) Muscle cells have a airly low radiosensitivity, and nerve cells are the least radiosensitive in the body (in etal li e, however, nerve cells are highly radiosensitive). Lymphocytes, a type o white blood cell concerned with the immune system, have the greatest radiosensitivity o all body cells. Spermatids are also highly radiosensitive, although not to the same degree as lymphocytes. 129. (B) Cathartics are used to stimulate de ecation (bowel movements). Emetics, such as ipecac, unction to induce vomiting. Diuretics are used to promote urine elimination in individuals whose tissues are retaining excessive uid. And antitussives are used to inhibit coughing. 130. (C) X-ray tube targets are constructed according to the line- ocus principle—the ocal spot is angled (usually 12–17 degrees) to the vertical. As the actual ocal spot is projected downward, it is oreshortened; thus, the e ective ocal spot is smaller than the actual ocal spot. As the ocal spot is projected toward the cathode end o the x-ray beam, it becomes larger and approaches its actual size. Figure 6-22 illustrates the variation o the e ective ocalspot size along the longitudinal tube axis. As the e ective ocal spot becomes larger toward the cathode end, the images o the phalanges illustrate gradual loss o recorded detail.

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Figure 6-22. From the American College o Radiology Learning File. Courtesy o the ACR.

131. (D) Extravasation occurs when medication or contrast medium is injected into the tissues surrounding a vein rather than into the vein itsel . It can happen when the patient’s veins are particularly deep and/or small. I this happens, the needle should be removed, pressure applied to prevent ormation o a hematoma, and then hot packs applied to relieve pain. 132. (D) Weight-bearing lateral projections o the oot are requested o en to evaluate the longitudinal

arch structure o the oot. T e patient stands on a small plat orm. T e x-ray cassette is placed between the eet, in a slot provided on the plat orm, with the top o the cassette against the medial aspect o the oot. T e CR is directed to enter the lateral aspect o the oot perpendicular to the base o the h metatarsal and to exit the medial side o the oot. 133. (C) T e gure is an AP projection o the le hip. T e leg is internally rotated, placing the emoral neck parallel to the IR. T e labels indicate the

Answers: 131–141

ollowing anatomic parts: A, sacroiliac joint; B, anterior in erior iliac spine; C, emoral head; D, greater trochanter; E, intertrochanteric crest; F, lesser trochanter; G, emoral neck; H, ischial tuberosity; I, obturator oramen; J, pubis; K, greater sciatic notch. 134. (C) Lead aprons are secondary radiation barriers and must contain at least 0.25-mm Pb equivalent, usually in the orm o lead-impregnated vinyl (according to CFR 20). Many radiology departments routinely use lead aprons containing 0.5 mm Pb (the NCRP recommends 0.5-mm Pb equivalent minimum). T ese aprons are heavier, but they attenuate a higher percentage o scattered radiation. 135. (A) T e type o isolation practiced to prevent the spread o in ectious agents in aerosol orm is respiratory isolation. A mask is suf cient protection rom aerosol transmission o pathogens. Protective isolation, also re erred to as reverse isolation, is used to protect patients whose immune systems are compromised. Patients receiving chemotherapy, burn patients, or patients who are human immunode ciency virus (HIV)–positive all may have compromised immune systems. Contact isolation is used when there is a chance that in ection may be spread by contact with body uids. Gloves and a gown are used, and goggles and masks may be necessary i there is a chance o uids spraying, such as in biopsy or drainage. Strict isolation is practiced with highly contagious diseases or viruses that may be spread by air and/or contact. 136. (B) Stochastic e ects o radiation are nonthreshold and randomly occurring. Examples o stochastic e ects include carcinogenesis and genetic e ects. T e chance o occurrence o stochastic e ects is directly related to the radiation dose; that is, as radiation dose increases, there is a greater likelihood o genetic alterations or development o cancer. Nonstochastic e ects are predictable threshold responses; that is, a certain quantity o radiation must be received be ore the e ect will occur, and the greater the dose, the more severe is the e ect. 137. (D) T e cycle o in ection includes our components—a susceptible host, a reservoir o in ection, a pathogenic organism, and a means o transmission. Pathogenic organisms are microscopic and

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include bacteria, ungi, and viruses. T e reservoir o in ection is the environment in which the microorganism thrives; this can be the human body. A susceptible host may have reduced resistance to in ection. T e means o transmission is either direct (touch) or indirect (vector, omite, airborne). 138. (D) T e ability o x-ray photons to penetrate a body part has a great deal to do with the composition o that part (e.g., bone vs. so tissue vs. air) and the presence o any pathologic condition. Pathologic conditions can alter the normal nature o the anatomic part. Some conditions, such as osteomalacia, brosarcoma, and paralytic ileus (obstruction), result in a decrease in body tissue density. When body tissue density decreases, x-rays will penetrate the tissues more readily; that is, there is more x-ray penetrability. In conditions such as ascites, where body tissue density increases as a result o the accumulation o uid, x-rays will not readily penetrate the body tissues; that is, there is less x-ray penetrability. 139. (A) Hematemesis re ers to vomiting blood. I the blood is dark in color, it is probably gastric in origin; i it is bright red, it is most likely pharyngeal in origin. Expectoration (coughing or spitting up) o blood is called hemoptysis. Blood is originating rom the mouth, larynx, or respiratory structure. Hematuria is the condition o blood in the urine. Epistaxis is the medical term or nosebleed. 140. (D) T e pulmonary apices are o en at least partially obscured by the clavicles. o visualize the entire lung apex and any suspicious areas, the clavicles must be “removed.” T is can be accomplished with the AP axial lordotic position. T rough the arching o the patient’s back and the cephalad angulation, the clavicles are projected upward and out o the pulmonary apices. Decubitus positions are used primarily to see air– uid levels. Lateral and dorsal decubitus positions show uid in the side that is down and air in the side that is up. 141. (D) A transthoracic projection is used to obtain a lateral projection o the upper hal to two-thirds o the humerus when the arm cannot be abducted. T e a ected arm is placed next to the upright Bucky, the una ected arm rests on the head, and the CR is directed horizontally through the thorax,

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exiting the upper humerus. T e superoin erior and in erosuperior projections o the shoulder both require abduction o the arm. 142. (C) T e radiographic subject, the patient, is composed o many di erent tissue types o varying densities (i.e., subject contrast), resulting in varying degrees o photon attenuation and absorption. T is di erential absorption contributes to the various shades o gray (i.e., scale o radiographic contrast) on the nished image. Normal tissue density may be signi cantly altered in the presence o pathology. For example, destructive bone disease can cause a dramatic decrease in tissue density. Abnormal accumulation o uid (as in ascites) will cause a signi cant increase in tissue density. Muscle atrophy or highly developed muscles similarly will decrease or increase tissue density. 143. (C) T e thoracic intervertebral (disk) spaces are demonstrated in the AP and lateral projections, although they are probably best demonstrated in the lateral projection. T e thoracic apophyseal joints are 70 degrees to the MSP and are demonstrated in a steep (70-degree) oblique position. T e thoracic intervertebral oramina, ormed by the vertebral notches o the pedicles, are 90 degrees to the MSP. T ey are, there ore, well demonstrated in the lateral position. 144. (D) T e posterior oblique positions (i.e., LPO and RPO) o the lumbar vertebrae demonstrate the apophyseal joints closer to the IR. T e le apophyseal joints are demonstrated in the LPO position, whereas the right apophyseal joints are demonstrated in the RPO position. T e lateral position is use ul to demonstrate the intervertebral disk spaces, intervertebral oramina, and spinous processes. 145. (B) Digital uoroscopy utilizes exposure, rather than continuous uoroscopic exposure. DF photospot images, which are simply still- rame images, require less patient dose (unless more than necessary are taken), and o er postprocessing capability. DF also o ers “road-mapping” capability—a technique use ul in procedures involving guidewire/ catheter placement. Another eature is the “last image hold” eature. During the uoroscopic examination, the most recent uoroscopic image can be stored on the monitor (“last image hold”), thereby reducing the need or continuous x-ray exposure.

T is technique can o er signi cant reductions in patient and personnel radiation exposure. T e length o the procedure is an important consideration in patient dose; the longer the procedure the greater the dose. 146. (C) A grid is a thin wa er placed between the patient and the IR to collect scattered radiation. It is made o alternating strips o lead and a radiolucent material such as plastic or aluminum. I the interspace material also were made o lead, little or no radiation would reach the IR, and no image would be ormed. 147. (D) Whenever a radiation worker could receive 10% or more o the annual EDE limit, that person must be provided with a radiation monitor. T e annual EDE limit or radiation workers is 50 mSv (5 rem, 5,000 mrem), but it is the responsibility o the radiographer to practice the ALARA principle, that is, to keep radiation dose as low as reasonably achievable. 148. (B) Beam restriction is used to determine the size o the x-ray eld. T is size never should be larger than the IR size. Because the size o the irradiated area can be made smaller, patient dose is reduced. Beam restriction reduces the production o scattered radiation that leads to og and, there ore, improves contrast resolution. Spatial resolution is related to actors a ecting recorded detail, not contrast resolution. 149. (D) An increase in technical actors will be required when imaging pathologic conditions that cause greater attenuation o the x-ray beam. T e x-ray beam su ers more attenuation as the thickness and/ or density o the tissues increases. Examples include conditions involving an increase in part size as a result o uid accumulation (edema) ollowing trauma, an accumulation o uid in the abdomen (ascites), or an increase in bone size and density (acromegaly) as a result o an endocrine disorder. T e radiographer needs a good working knowledge o pathologic conditions, their e ect on the body, and the resulting modi cations in technical actors required. 150. (B) A radiographer who discloses con dential in ormation to unauthorized individuals may be ound guilty o invasion o privacy. I the disclosure

Answers: 142–159

is in some way detrimental or otherwise harm ul to the patient, the radiographer may be accused o de amation. Spoken de amation is slander; written de amation is libel. Assault is to threaten harm; battery is to carry out the threat. 151. (B) All our medications are ound routinely on the typical emergency cart. Heparin is used to decrease coagulation and o en used in the cardiovascular imaging suite to inhibit coagulation on catheters. Norepinephrine unctions to raise the blood pressure, whereas nitroglycerin unctions as a vasodilator, relaxing the walls o blood vessels and increasing circulation. Lidocaine is used as a local anesthetic or antidysrhythmic. 152. (B) Focal-spot blur, or geometric blur, is caused by photons emerging rom a large ocal spot. Because the projected ocal spot is greatest at the cathode end o the x-ray tube, geometric blur is also greatest at the corresponding part (cathode end) o the radiograph. T e projected ocal-spot size becomes progressively smaller toward the anode end o the x-ray tube. 153. (B) T e image intensi er can be coupled to the V camera via a ber-optic bundle or via a lens coupling device. Advantages o the ber-optic connection include less ragility, more compactness, and ease o maneuverability. T e big advantage o the objective lens is that it allows the use o auxiliary imaging devices such as a cine camera or spotlm camera. 154. (A) T e photoelectric e ect and Compton scattering are the two predominant interactions between x-ray photons and matter in diagnostic radiology. In the photoelectric e ect, the low–energy-incident photon is absorbed by the tissues being radiographed. In Compton scatter, the high–energyincident photon uses only part o its energy to eject an outer-shell electron. It retains much o its original energy in the orm o a scattered x-ray. Radiologic personnel can be exposed to that high-energy scattered radiation, especially in uoroscopy and mobile radiography. Lead aprons are used to protect us rom exposure to scattered radiation during these procedures. 155. (C) T e bones o the oot include the 7 tarsal bones, 5 metatarsal bones, and 14 phalanges. T e

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base o the h metatarsal has a prominent tuberosity (number 4), which is a common racture site. T ere are two sesamoid bones (number 5) located within the exor tendon just proximal to the rst metatarsophalangeal joint. T e calcaneus (os calsis), or heel bone, is the largest tarsal (numbers 6 and 7). It serves as attachment or the Achilles tendon posteriorly, articulates anteriorly with the cuboid bone (number 3), presents three articular sur aces superiorly or its articulation with the talus (number 1), and has a prominent shel on its anteromedial edge called the sustentaculum tali. T e in erior sur ace o the talus (astragalus) articulates with the superior calcaneus to orm the three- aceted subtalar joint. T e talus also articulates anteriorly with the navicular (number 2). Articulating anteriorly with the navicular are the three cunei orm bones—medial/ rst, intermediate/second, and lateral/third. T e navicular articulates laterally with the cuboid. 156. (A) Location o the heels o the hands is o great importance during CPR. T ey should be placed about 11⁄2 in superior to the xiphoid tip. In this way, the heart will receive the compressions it requires without causing internal injuries. Rib ractures can depress and cause injury to the lung tissues within the rib cage. 157. (A) OID can a ect receptor exposure when OID acts as an air gap. I a 6-in air gap is introduced between the part and IR, much o the scattered radiation emitted rom the part will not reach the IR, as shown in Figure 6-23. T e OID thus is acting as a low-ratio grid and receptor exposure is thereore decreased. 158. (B) For an AP projection o the hip, two bony landmarks are used. T e CR is directed perpendicular to a point located 2 in medial to the ASIS at the level o the greater trochanter. A point midway between the iliac crest and the pubic symphysis is too superior and medial to coincide with the hip articulation. 159. (B) In lm/screen imaging, a 15% change in kilovoltage, one way or the other, can have signi cant radiographic impact according to the 15% rule. An increase o 15% in kV will e ectively double the density; a decrease o 15% will reduce the density by one-hal . So, in this instance, i the kV is

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Air ga p

Figure 6-23.

increased by 15%, exposure to the image receptor will be doubled—there ore, the mAs should be reduced by hal (changed rom 32 to 16 mAs) to compensate or the exposure change. 160. (D) T e shortest possible exposure time should be used to minimize motion unsharpness. Motion causes unsharpness that destroys detail. Care ul and accurate patient instruction is essential or minimizing voluntary motion. Suspended respiration eliminates respiratory motion. Using the shortest possible exposure time is essential to decreasing involuntary motion. Immobilization also can be use ul in eliminating motion unsharpness. 161. (A) Oral administration o barium sul ate is used to demonstrate the upper digestive system, esophagus, undus, and body and pylorus o the stomach and barium progression through the small bowel/ intestine. T e small intestine is composed o the duodenum, jejunum, and ileum. T e duodenum is the shortest portion, beginning just beyond the

pyloric sphincter and dividing into our portions— the duodenal cap or bulb, the descending duodenum, the transverse duodenum, and the ascending duodenum. T ese portions orm a C-shaped loop that is occupied by the head o the pancreas. T e descending portion receives the hepatopancreatic ampulla and duodenal papilla. T e ascending portion terminates at the duodenojejunal exure (angle o reitz). Whereas the position o the short (9 in) duodenum is xed, the jejunum (9 ) and ileum (13 ) are very mobile. T e large bowel, including the cecum, usually is demonstrated via rectal administration o barium. T e approximately 5- -long large intestine (colon) begins at the terminus o the small intestine; its rst portion is the dilated saclike cecum, located in erior to the ileocecal valve. Projecting posteromedially rom the cecum is the short vermi orm appendix. T e ascending colon is continuous with the cecum, bending and orming the right colic (hepatic) exure. T e colon traverses the abdomen as the transverse colon and bends to orm the le colic (splenic) exure. T e descending colon continues down the le side and moves medially to orm the S-shaped sigmoid colon. T e rectum is that part o the large intestine, approximately 5 in. in length, between the sigmoid and the anal canal. T e ilium is the bony pelvis, whereas the ileum is the small bowel—which would be demonstrated by oral administration o barium. 162. (C) T e latent image is the invisible image produced within the lm emulsion as a result o exposure to radiation. T e developer solution converts this to a visible mani est image. T e exposed silver halide grains in the emulsion undergo chemical change in the developer solution, and the unexposed crystals are removed rom the lm during the xing process. 163. (A) T e image intensi er’s input phosphor is 6 to 9 times larger than the output phosphor. It receives the remnant radiation emerging rom the patient and converts it into a uorescent light image. Very close to the input phosphor, separated only by a thin, transparent layer, is the photocathode. T e photocathode is made o a photoemissive alloy, usually a cesium and antimony compound. T e uorescent light image strikes the photocathode and is converted to an electron image, which is ocused by the electrostatic lenses to the small output phosphor.

Answers: 160–169

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164. (D) Adverse reactions to the intravascular administration o iodinated contrast medium are not uncommon, but although the risk o a li ethreatening reaction is relatively rare, the radiographer must be alert to recognize and deal e ectively with a serious reaction should it occur. Flushed appearance and nausea, occasionally vomiting, and a ew hives characterize a minor reaction. Early symptoms o a possible anaphylactic reaction include constriction o the throat, possibly owing to laryngeal edema, dysphagia (dif culty in swallowing), and itching o the palms and soles. T e radiographer must maintain the patient’s airway, summon the radiologist, and call a “code.”

166. (B) A stethoscope and a sphygmomanometer are used together to measure blood pressure. T e sphygmomanometer’s cu is placed around the midportion o the upper arm. T e cu is in ated to a value higher than the patient’s systolic pressure to temporarily collapse the brachial artery. As the in ation is gradually released, the rst sound heard is the systolic pressure; the normal range is 110 to 140 mm Hg. When no more sound is heard, the diastolic pressure is recorded. T e normal diastolic range is 60 to 90 mm Hg. Elevated blood pressure is called hypertension. Hypotension, low blood pressure, is not o concern unless it is caused by injury or disease; in that case, it can result in shock.

165. (B) As OID increases, magni cation increases. Viscera and structures within the body will be varying distances rom the IR depending on their location within the body and the position used or the exposure. T e size o a particular structure or image can be calculated using the ollowing ormula:

167. (B) A polyp is a tumor with a pedicle (stalk) that is ound commonly in vascular organs projecting inward rom its mucosal wall. Polyps usually are removed surgically because, although usually benign, they can become malignant. A diverticulum is an outpouching rom the wall o an organ, such as the colon. A stula is an abnormal tube-like passageway between organs or between an organ and the sur ace. An abscess is a localized collection o pus as a result o in ammation.

Image size SID = Object size SOD (SOD = SID − OID) Substituting known quantities: 9 cm 105 cm = x cm 87 cm 105x = 783 T us, x = 7.45 cm (approximate actual size). T e relationship between SID, SOD, and OID is illustrated in Figure 6-24. CR

S OD

S ID Obje ct/pa rt

Ima ge re ce ptor/ima ge

Figure 6-24.

168. (A) T e autotrans ormer (number 1) controls/ selects the amount o voltage sent to the primary winding o the high-voltage trans ormer and operates on the principle o sel -induction. T e step-up (high-voltage) trans ormer (primary coil is number 2; secondary coil is number 3) operates on the principle o mutual induction. T e step-up transormer unctions to change low voltage to the high voltage necessary to produce x-ray photons. T e x-ray tube is identi ed as number 7. 169. (C) In the simpli ed x-ray circuit shown, the autotrans ormer is labeled number 1, the primary coil o the high-voltage trans ormer is number 2, and the secondary coil is labeled number 3. T e autotrans ormer selects the voltage that will be sent to the high-voltage trans ormer to be stepped up to the thousands o volts required or x-ray production. At the midpoint o the secondary coil is the grounded milliamperage meter (number 4). Since the milliamperage meter is in the control panel and is associated with high voltage, it must be grounded. T e recti cation system, which is used to change alternating current to unidirectional current, is indicated by the number 5. T e recti cation system

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is located between the secondary coil o the high-voltage trans ormer (number 3) and the x-ray tube (number 7). 170. (D) All these conditions are considered technically additive because they all involve an increase in tissue density. Osteoma, or exostosis, is a (usually benign) bony tumor that can develop on bone. Bronchiectasis is a chronic dilatation o the bronchi with accumulation o uid. Pneumonia is in ammation o the lung(s) with accumulation o uid. Additional bony tissues and the pathologic presence o uid are additive pathologic conditions and require an increase in technical actors. Destructive conditions such as osteoporosis require a decrease in technical actors. 171. (A) T e shorter the SID, the greater is the skin dose (ESE). T is is why there are speci c SSD restrictions in uoroscopy. X-ray beam quality has a signi cant e ect on patient skin dose. T e use o high kilovoltage produces more high-energy penetrating photons, thereby decreasing skin dose. Filtration is used to remove the low-energy photons that contribute to skin dose rom the primary beam. Although milliamperage regulates the number o x-ray photons produced, it does not a ect photon quality. 172. (D) Breast tissue has very low subject contrast, but it is imperative to visualize micro-calci cations and subtle density di erences. Fine detail is necessary to visualize any micro-calci cations; there ore, a small ocal-spot tube is essential. High, short-scale contrast (and, there ore, low kilovoltage) is needed to accentuate minute di erences in tissue density. A compression device serves to even out di erences in tissue thickness (thicker at the chest wall, thinner at the nipple) and decrease OID and helps to decrease the production o scattered radiation. 173. (D) Some medications cannot be taken orally. T ey may be destroyed by the GI juices or may irritate the GI tract. Medications that are administered by any route other than orally are said to be given parenterally. T is can include intravenous, intramuscular, topical, intrathecal, or subcutaneous modes o medication administration. 174. (D) Single-phase radiographic equipment is much less ef cient than three-phase equipment because

it has a 100% voltage ripple. With three-phase equipment, voltage never drops to zero, and x-ray intensity is signi cantly greater. o produce similar density, only two-thirds o the original milliampere-seconds would be used or three-phase, sixpulse equipment (2⁄3 × 8 = 5.3 mAs). With three-phase, 12-pulse equipment, the original milliampere-seconds would be cut in hal (1⁄2 × 8 = 4 mAs). 175. (B) A ractional ocal spot o 0.3 mm or smaller is essential or reproducing ne detail without ocalspot blurring in magni cation radiography. As the object image is magni ed, so will be the associated blur unless the ractional ocal spot is used. Fluoroscopic procedures probably would cause great wear on a ractional ocal spot. Use o the ractional ocal spot is not essential in bone radiography, although magni cation o bony structures o en is help ul in locating hairline ractures. 176. (B) SF/analog imaging uses an area x-ray beam, but the IR is lm emulsion sandwiched between intensi ying screens in a cassette. Computed radiography (CR) also uses an area x-ray beam, but the IR is a photostimulable phosphor such as europium-activated barium uorohalide coated on an image plate. Digital radiography (DR) can use an area x-ray beam detected by a direct-capture solid-state device—there are no traditional cassette-like devices. DR can also use a an-shaped x-ray beam. T e an-shaped beam is “read” by a linear array o detectors. 177. (D) It is important to note that histogram appearance as well as patient dose can be a ected by the radiographer’s knowledge and skill using digital imaging, in addition to his or her degree o accuracy in positioning and centering. Collimation is exceedingly important to avoid histogram analysis errors. Lack o adequate collimation can result in signals outside the anatomical area being included in the exposure data recognition/histogram analysis. T is can result in a variety o histogram analysis errors, including excessively light, dark, or noisy images. 178. (A) X-rays produced in the x-ray tube make up a heterogeneous beam. T ere are many low-energy, or “so ,” photons that do not contribute to the radiographic image because they never reach the IR. Instead, they stay in the patient, contributing to

Answers: 170–186

skin dose. It is these photons that are removed by (aluminum) ltration. 179. (B) T e e ects o a quantity o radiation delivered to a body depend on several actors—the amount o radiation received, the size o the irradiated area, and how the radiation is delivered in time. I the radiation is delivered in portions over a period o time, it is said to be ractionated and has a less harm ul e ect than i the radiation were delivered all at once. With ractionation, cells have an opportunity to repair, so some recovery occurs between doses. 180. (D) Generally speaking, anatomic parts measuring in excess o 10 cm require a grid. (T e major exception to this rule can be the chest). T e larger the part, the more scattered radiation is generated. o avoid degradation o the image as a result o scattered radiation og, a grid is used to absorb scatter. Parts generally requiring the use o a grid include the skull, spine, ribs, pelvis, shoulder, and emur. 181. (D) Quality Control re ers to our equipment and its sa e and accurate operation. Various components must be tested at speci ed intervals and test results must be within speci ed parameters. Any deviation rom those parameters must be corrected. Examples o equipment components that are tested annually are the ocal-spot size, linearity, reproducibility, ltration, kV, and exposure time. Congruence is a term used to describe the relationship between the collimator light eld and the actual x-ray eld—they must be congruent (i.e., match) to within 2% o the SID. Radiographic equipment collimators should be inspected and veri ed as accurate semiannually, that is, twice a year. Kilovoltage settings can most e ectively be tested using an electronic kV meter; to meet required standards, the kV should be accurate to within + /–4 kV. Reproducibility testing should speci y that radiation output be consistent to within + /–5%. 182. (B) Magni cation radiography is used to enlarge details to a more perceptible degree. Hairline ractures and minute blood vessels are candidates or magni cation radiography. T e problem o magnication unsharpness is overcome by using a ractional ocal spot; larger ocal-spot sizes will produce

347

excessive blurring unsharpness. Grids are usually unnecessary in magni cation radiography because o the air-gap e ect produced by the OID. Direct-exposure technique probably would not be used because o the excessive exposure required. 183. (B) T e internal rotation position places the humeral epicondyles perpendicular to the IR, the humerus in a true lateral position, and the lesser tubercle in pro le. T e external rotation position places the humeral epicondyles parallel to the IR, the humerus in a true AP position, and the greater tubercle in pro le. T e neutral position is used o en or the evaluation o calcium deposits in the shoulder joint. 184. (A) T e lead strips in a ocused grid are made to parallel the x-ray beam. T ere ore, scattered radiation, which radiates in directions other than that o the primary beam, will be absorbed by the grid. When the x-ray beam does not parallel the lead strips, some type o grid cuto occurs. I the x-ray beam is not centered to the grid, or i the x-ray tube and grid sur ace are not parallel (level), there will be a airly uni orm decrease in radiographic density across the entire image. However, i the grid is not used within its recommended SID ( ocus) range (i.e., i the SID is too great or too little), there will be a decrease in density at the periphery o the image. 185. (D) T e stomach is normally angled with the undus lying posteriorly and the body, pylorus, and duodenum in erior to the undus and angling anteriorly. T ere ore, when the patient ingests barium and lies AP recumbent, the heavy barium gravitates easily to the undus and lls it. With the patient PA recumbent, barium gravitates in eriorly to the body, pylorus, and duodenum, displacing air into the undus. 186. (D) X-ray tubes are diode tubes; that is, they have two electrodes—a positive electrode called the anode and a negative electrode called the cathode. T e cathode lament is heated to incandescence and releases electrons, a process called thermionic emission. During the exposure, these electrons are driven by thousands o volts toward the anode, where they are suddenly decelerated. T is deceleration is what produces x-rays. Some x-ray tubes, such as those used in uoroscopy and in capacitor-discharge

348

6: Practice Test 1

mobile units, are required to make short, precise – sometimes, multiple – exposures. T is need is met by using a grid-controlled tube. A grid-controlled tube uses the molybdenum ocusing cup as the switch, permitting very precise control o the tube current ( ow o electrons between cathode and anode). 187. (B) T e gure illustrates a lateral thoracic spine. Motion rom “breathing technique” has been employed to blur out the superimposed pulmonary vascular markings and bony rib details in order to better demonstrate the bony structure o the thoracic spine. Since the shoulder area o the upper thoracic spine is so much thicker and more dense than the lower thoracic area, employment o the anode heel e ect is also a valuable tool here. T e thicker shoulder area is placed under the more intense cathode end o the x-ray beam, and the thinner anatomic part is placed under the anode end o the x-ray beam. 188. (D) All three pathologic conditions involve processes that render tissues more easily penetrated by the x-ray beam. Pneumothorax is a collection o air or gas in the pleural cavity. Emphysema is a chronic pulmonary disease characterized by an increase in the size o the air-containing terminal bronchioles. T ese two conditions add air to the tissues, making them more easily penetrated. Multiple myeloma is a condition characterized by in ltration and destruction o bone and marrow. Each o these conditions requires that actors be decreased rom the normal to avoid overexposure.

image plate is not light sensitive. T e cassette has a thin lead- oil backing (similar to traditional cassettes) to absorb backscatter. Inside the cassette is the photostimulable phosphor (PSP) image plate, sometimes re erred to simply as an image plate (IP). T is PSP or IP within the cassette has a layer o europium-activated barium uorohalide that serves as the IR as it is exposed in the traditional manner and receives the latent image. T e PSP can store the latent image or several hours; a er about 8 hours, noticeable image ading will occur. 191. (D) T e greater the number o electrons making up the electron stream and bombarding the target, the greater is the number o x-ray photons produced. Although kilovoltage usually is associated with the energy o the x-ray photons because a greater number o more energetic electrons will produce more x-ray photons, an increase in kilovoltage will also increase the number o photons produced. Speci cally, the quantity o radiation produced increases as the square o the kilovoltage. T e material composition o the tube target also plays an important role in the number o x-ray photons produced. T e higher the atomic number, the denser and more closely packed are the atoms making up the material, and there ore, the greater is the chance o an interaction between a high-speed electron and the target material.

189. (C) Diuretics are used to promote urine elimination in individuals whose tissues are retaining excessive uid. T ey are used in treating hypertension, congestive heart ailure, and edema. Cathartics are used to stimulate de ecation (bowel movements); they are used as preparation or some x-ray examinations such as barium enemas. Emetics unction to induce vomiting, and antitussives are used to inhibit coughing.

192. (D) Radiographic rating charts enable the operator to determine the maximum sa e milliamperage, exposure time, and kilovoltage or a particular exposure using a particular x-ray tube. An exposure that can be made using the large ocal spot may not be sa e when the small ocal spot o the same x-ray tube is used. T e total number o heat units an exposure generates also in uences the amount o stress (in the orm o heat) imparted to the anode. Single-phase heat units are determined by the product o milliamperage × time × kilovoltage. T ree-phase and high- requency heat units are determined rom the product o milliamperage × time × kilovoltage × 1.4.

190. (B) Computed radiography (CR) cassettes use no intensi ying screens or lm—hence, the term lmless radiography. T e cassettes have a protective unction ( or the image plate within) and can be used in the Bucky tray or directly under the anatomic part; they need not be light-tight because the

193. (C) T e lateral lumbar position is use ul to demonstrate the intervertebral disk spaces, intervertebral oramina, and spinous processes. T e posterior oblique positions (i.e., LPO and RPO) o the lumbar vertebrae demonstrate the apophyseal articulations closer to the IR. T e le

Answers: 187–200

apophyseal articulations are demonstrated in the LPO position, whereas the right apophyseal articulations are demonstrated in the RPO position. 194. (A) T e control badge that comes with the month’s supply o dosimeters is used as a standard or comparison with the used personal badges. T e control badge should be stored in a radiation- ree area, away rom the radiographic rooms. When it has been processed, its density is compared with the densities o the monitors worn in radiation areas. Densities greater than the density o the radiation- ree monitor are reported in millirem units. 195. (D) According to the patient’s bill o rights, the patient’s verbal request supersedes any prior written consent. It is not appropriate to dismiss the patient without noti ying the re erring physician and the radiologist. T e patient may very well need a particular radiographic examination to make a proper diagnosis or or preoperative planning, and the radiographer must in orm the physician o the patient’s decision immediately. 196. (B) T e input phosphor o an image intensi er receives remnant radiation emerging rom the patient and converts it to a uorescent light image. Directly adjacent to the input phosphor is the photocathode, which is made o a photoemissive alloy (usually, a cesium and antimony compound). T e uorescent light image strikes the photocathode and is converted to an electron image. T e

349

electrons are care ully ocused, to maintain image resolution, by the electrostatic ocusing lenses, through the accelerating anode and to the output phosphor or conversion back to light. 197. (B) Resolution describes how closely ne details may be associated and still be recognized as separate details be ore seeming to blend into each other and appear as one. T e degree o resolution transerred to the image receptor is a unction o the resolving power o each o the system components and can be expressed in line pairs per millimeter (lp/mm), line-spread unction (LSP), or modulation trans er unction (M F). Line pairs per millimeter can be measured using a resolution test pattern; a number o resolution test tools are available. LSP is measured using a 10-µm x-ray beam; M F measures the amount o in ormation lost between the object and the IR. 198–200. (198, C; 199, D; 200, C) T e gure illustrates the x-ray tube component parts. Number 1 indicates the thoriated tungsten lament, which unctions to release electrons when heated. Number 2 is the nickel ocusing cup, which directs these electrons toward the anode’s ocal track. Number 4 is the rotating anode, and number 5 is the anode’s ocal track. T e ocal track is made o thoriated ( or extra protection rom heat) tungsten. When high-speed electrons are suddenly decelerated at the target, their kinetic energy is changed to x-ray photon energy.

Subspecialty List

QUESTION NUMBER AND SUBSPECIALTY correspond to subcategories in each o the f ve ARRT examination specif cation sections 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30.

350

Image acquisition and evaluation Patient care and education Imaging procedures Image acquisition and evaluation Equipment operation and quality control Radiation protection Image acquisition and evaluation Imaging procedures Radiation protection Imaging procedures Radiation protection Image acquisition and evaluation Equipment operation and quality control Radiation protection Equipment operation and quality control Imaging procedures Imaging procedures Imaging procedures Imaging procedures Image acquisition and evaluation Image acquisition and evaluation Equipment operation and quality control Patient care and education Imaging procedures Image acquisition and evaluation Radiation protection Radiation protection Radiation protection Patient care and education Equipment operation and quality control

31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65.

Patient care and education Imaging procedures Imaging procedures Radiation protection Patient care and education Radiation protection Patient care and education Image acquisition and evaluation Patient care and education Imaging procedures Imaging procedures Image acquisition and evaluation Imaging procedures Imaging procedures Equipment operation and quality control Equipment operation and quality control Patient care and education Radiation protection Image acquisition and evaluation Patient care and education Patient care and education Equipment operation and quality control Equipment operation and quality control Radiation protection Imaging procedures Patient care and education Image acquisition and evaluation Imaging procedures Image acquisition and evaluation Image acquisition and evaluation Imaging procedures Equipment operation and quality control Equipment operation and quality control Patient care and education Image acquisition and evaluation

Subspecialty List

66. 67. 68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 78. 79. 80. 81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92. 93. 94. 95. 96. 97. 98. 99. 100. 101. 102. 103. 104. 105. 106. 107. 108. 109. 110. 111. 112. 113. 114. 115. 116.

Patient care and education Patient care and education Equipment operation and quality control Equipment operation and quality control Image acquisition and evaluation Radiation protection Image acquisition and evaluation Patient care and education Equipment operation and quality control Equipment operation and quality control Equipment operation and quality control Image acquisition and evaluation Radiation protection Radiation protection Imaging procedures Equipment operation and quality control Equipment operation and quality control Imaging procedures Image acquisition and evaluation Imaging procedures Equipment operation and quality control Image acquisition and evaluation Image acquisition and evaluation Patient care and education Equipment operation and quality control Equipment operation and quality control Equipment operation and quality control Imaging procedures Radiation protection Patient care and education Equipment operation and quality control Image acquisition and evaluation Equipment operation and quality control Equipment operation and quality control Equipment operation and quality control Patient care and education Patient care and education Imaging procedures Imaging procedures Equipment operation and quality control Radiation protection Image acquisition and evaluation Imaging procedures Radiation protection Imaging procedures Radiation protection Image acquisition and evaluation Equipment operation and quality control Image acquisition and evaluation Image acquisition and evaluation Imaging procedures

117. 118. 119. 120. 121. 122. 123. 124. 125. 126. 127. 128. 129. 130. 131. 132. 133. 134. 135. 136. 137. 138. 139. 140. 141. 142. 143. 144. 145. 146. 147. 148. 149. 150. 151. 152. 153. 154. 155. 156. 157. 158. 159. 160. 161. 162. 163. 164. 165. 166. 167.

Imaging procedures Imaging procedures Imaging procedures Image acquisition and evaluation Image acquisition and evaluation Equipment operation and quality control Patient care and education Imaging procedures Image acquisition and evaluation Radiation protection Radiation protection Radiation protection Patient care and education Equipment operation and quality control Patient care and education Imaging procedures Imaging procedures Radiation protection Patient care and education Radiation protection Patient care and education Image acquisition and evaluation Patient care and education Imaging procedures Imaging procedures Image acquisition and evaluation Imaging procedures Imaging procedures Equipment operation and quality control Equipment operation and quality control Radiation protection Image acquisition and evaluation Image acquisition and evaluation Patient care and education Patient care and education Equipment operation and quality control Equipment operation and quality control Radiation protection Imaging procedures Patient care and education Image acquisition and evaluation Imaging procedures Image acquisition and evaluation Imaging procedures Patient care and education Equipment operation and quality control Equipment operation and quality control Patient care and education Image acquisition and evaluation Patient care and education Patient care and education

351

352

168. 169. 170. 171. 172. 173. 174. 175. 176. 177. 178. 179. 180. 181. 182. 183. 184.

6: Practice Test 1

Equipment operation and quality control Equipment operation and quality control Image acquisition and evaluation Radiation protection Image acquisition and evaluation Patient care and education Image acquisition and evaluation Equipment operation and quality control Equipment operation and quality control Image acquisition and evaluation Radiation protection Radiation protection Imaging procedures Radiation protection Equipment operation and quality control Imaging procedures Image acquisition and evaluation

185. 186. 187. 188. 189. 190. 191. 192. 193. 194. 195. 196. 197. 198. 199. 200.

Imaging procedures Equipment operation and quality control Image acquisition and evaluation Image acquisition and evaluation Patient care and education Equipment operation and quality control Equipment operation and quality control Equipment operation and quality control Imaging procedures Radiation protection Patient care and education Equipment operation and quality control Image acquisition and evaluation Equipment operation and quality control Equipment operation and quality control Equipment operation and quality control

CHAPTER 7

Practice Test 2 Questions

DIRECTIONS (Questions 1 through 200): Each of the numbered items or incomplete statements in this section is followed by answers or by completions of the statement. Select the one lettered answer or completion that is best in each case. 1. T e drug diphenhydramine is classi ed as a(n) (A) (B) (C) (D)

diuretic antipyretic antihistamine emetic

2. A graphic diagram o signal values representing various absorbing properties within the part being imaged is called a (A) (B) (C) (D)

processing algorithm DICOM histogram window

3. Another name or Hirschsprung disease, the most common cause o lower GI obstruction in neonates, is (A) (B) (C) (D)

intussusception volvulus congenital megacolon pyloric stenosis

4. A positive contrast agent 1. absorbs x-ray photons 2. is composed o elements having high atomic number 3. is seen as a dark area on the image (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

5. T e primary unction o (A) (B) (C) (D)

ltration is to reduce

patient skin dose operator dose image noise scattered radiation

6. Proper body mechanics includes a wide base o support. T e base o support is the portion o the body (A) in contact with the oor or other horizontal sur ace (B) in the midportion o the pelvis or lower abdomen (C) passing through the center o gravity (D) none o the above

353

354

7: Practice Test 2

7. T e mediolateral projection o the knee shown in Figure 7-1 could best be improved by

9. Geometric unsharpness will be least obvious 1. at long SIDs 2. with small ocal spots 3. at the anode end o the image

(A) rotating the patient orward (B) rotating the patient backward (C) angling the central ray (CR) about 5 degrees caudad (D) angling the CR about 5 degrees cephalad

(A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

10. Which o the dose–response curves shown in Figure 7-2 illustrate(s) a direct relationship between dose and response? 1. Curve number 1 2. Curve number 2 3. Curve number 3 (A) (B) (C) (D)

1 only 2 only 1 and 3 only 1, 2, and 3

1

Figure 7-1. Courtesy o Stam ord Hospital, Department o Radiology.

8. Which o the ollowing types o adult tissue is (are) comparatively insensitive to e ects o ionizing radiation?

R E S P O N S E

1. Epithelial tissue 2. Nerve tissue 3. Muscle tissue (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

DOS E

Figure 7-2.

2

3

Questions: 7–18

11. T e carpal scaphoid can be demonstrated in which o the ollowing projection(s) o the wrist?

15. T e housing surrounding an x-ray tube unctions to

1. PA oblique 2. PA with radial deviation 3. PA with elbow elevated 20 degrees

1. retain heat within the glass envelope 2. protect rom electric shock 3. keep leakage radiation to a minimum

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

12. A patient who has been recumbent or some time and gets up quickly may su er rom light-headedness or eel aint. T is is re erred to as (A) (B) (C) (D)

dyspnea orthopnea hypertension orthostatic hypotension

13. Which o the ollowing is a unctional study used to demonstrate the degree o AP motion present in the cervical spine? (A) (B) (C) (D)

Moving mandible position AP open-mouth projection Laterals in exion and extension AP right and le bending

14. Which o the ollowing is (are) evaluation criteria or a PA chest radiograph o the heart and lungs? 1. en posterior ribs should be seen above the diaphragm. 2. T e medial ends o the clavicles should be equidistant rom the vertebral column. 3. T e scapulae should be seen through the upper lung elds. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

355

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

16. When interviewing a patient, what is it that the healthcare pro essional can observe? (A) (B) (C) (D)

Symptoms History Objective signs Subjective signs

17. T e e ective energy o an x-ray beam is increased by increasing the 1. added ltration 2. kilovoltage 3. milliamperage (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

18. Which o the ollowing statements is true with regard to the two C images seen in Figure 7-3? 1. Image A illustrates more superior structures. 2. T e images are sagittal reconstructions. 3. T e examination was per ormed without arti cial contrast. (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 1, 2, and 3

356

7: Practice Test 2

1

1 2 3

2

4 5

3

6

4

7 8

5

9

6

10 11

A

B

Figure 7-3. A and B. Courtesy o Stam ord Hospital, Department o Radiology.

19. T e structure labeled number 7 in Figure 7-3, image B is the (A) (B) (C) (D)

IVC aorta spleen le kidney

20. Drugs that may be used to prolong blood clotting time include 1. heparin 2. diphenhydramine 3. lidocaine (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

21. Characteristics o a patient with pulmonary emphysema include 1. hyperventilation 2. increased AP diameter o the chest 3. shoulder girdle elevation (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

22. Which among the ollowing components is (are) part o the gantry o a C imaging system? 1. X-ray tube 2. Detector array 3. Control panel (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

23. Brightness and contrast resolution in digital imaging can be in uenced by 1. window level (WL) 2. window width (WW) 3. look-up table (LU ) (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

24. Which o the ollowing is the approximate skin dose or 5 minutes o uoroscopy per ormed at 1.5 mA? (A) (B) (C) (D)

3.7 rad 7.5 rad 15 rad 21 rad

Questions: 19–33

25.

o image suspected ree air within the abdominal cavity o an in ant, which o the ollowing projections o the abdomen will demonstrate the condition with the lowest patient dose? (A) (B) (C) (D)

PA erect with grid Right lateral decubitus with grid Right lateral decubitus without grid Recumbent AP without grid

26. An AP oblique projection (lateral rotation) o the elbow will demonstrate the 1. olecranon process within the olecranon ossa 2. capitulum o the humerus 3. radial head ree o superimposition (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

27. Which o the ollowing x-ray circuit devices operate(s) on the principle o mutual induction?

357

30. Which o the ollowing medication routes re ers to the term parenteral? 1. Subcutaneous 2. Intramuscular 3. Oral (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

31. T e position illustrated in Figure 7-4 can be used success ully to demonstrate the 1. PA oblique sternum 2. le anterior ribs 3. barium- lled gastric undus (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

1. High-voltage trans ormer 2. Filament trans ormer 3. Autotrans ormer (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

28. Pathologic or abnormal conditions that would require an increase in technical actors include all o the ollowing except (A) (B) (C) (D)

atelectasis pneumoperitoneum Paget disease congestive heart ailure

29. T e risk o inoculation with HIV is considered high or which o the ollowing entry sites? 1. Broken skin 2. Perinatal exposure 3. Accidental needle stick (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Figure 7-4.

32. T e AP axial projection o the pulmonary apices requires the CR to be directed (A) (B) (C) (D)

15 degrees cephalad 15 degrees caudad 30 degrees cephalad 30 degrees caudad

33. Which o the ollowing is an acceptable approximate entrance skin exposure (ESE) or a PA chest radiograph? (A) (B) (C) (D)

6 mR 20 mR 38 mR 0.6 R

358

7: Practice Test 2 A

B

C

1

–

3

2

5

4 7

+

6

Figure 7-5.

34.

ypical patient demographic and examination in ormation include(s) 1. type o examination 2. accession number 3. date and time o examination (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

35. Abdominal viscera located in the retroperitoneum include the 1. kidneys 2. duodenum 3. ascending and descending colon (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

36. T e act that x-ray intensity across the primary beam can vary as much as 45% describes the (A) (B) (C) (D)

line- ocus principle trans ormer law anode heel e ect inverse-square law

37. Which o the x-ray circuit devices shown in Figure 7-5 operates on the principle o sel -induction? (A) (B) (C) (D)

Number 1 Number 3 Number 5 Number 7

38. Re erring to the simpli ed x-ray circuit shown in Figure 7-5, what is indicated by the number 3? (A) (B) (C) (D)

Step-up trans ormer Autotrans ormer Filament circuit Recti cation system

39. Which o the ollowing is (are) characteristic(s) o anemia? 1. Decreased number o circulating red blood cells 2. Decreased hemoglobin 3. Hematuria (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

Questions: 34–48

40. Which o the ollowing terms/units is used to express the resolution o a diagnostic image? (A) (B) (C) (D)

Line pairs per millimeter (lp/mm) Speed Latitude Kiloelectronvolts (keV)

41. T e advantages o high- requency generators over earlier types o generators include 1. smaller size 2. nearly constant potential 3. lower patient dose (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2 and 3

42. A radiograph exposed using a 12:1 ratio grid may exhibit a loss o receptor exposure at its lateral edges because the (A) SID was too great (B) grid ailed to move during the exposure (C) x-ray tube was angled in the direction o the lead strips (D) CR was o -center 43. A signed consent orm is necessary prior to perorming all the ollowing procedures except (A) (B) (C) (D)

myelogram cardiac catheterization upper GI series interventional vascular procedure

45. Acceptable method(s) o unsharpness is (are)

minimizing motion

1. suspended respiration 2. short exposure time 3. patient instruction (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

46. In amorphous selenium at-panel detectors, the term amorphous re ers to a (A) crystalline material having typical crystalline structure (B) crystalline material lacking typical crystalline structure (C) toxic crystalline material (D) homogeneous crystalline material 47. T e National Council on Radiation Protection and Measurements (NCRP) recommends an annual occupational e ective (stochastic) dose equivalent limit o (A) (B) (C) (D)

50 mSv (5 rem) 100 mSv (10 rem) 25 mSv (2.5 rem) 200 mSv (20 rem)

48. T e image in Figure 7-6 was obtained while testing (A) (B) (C) (D)

recti er operation o a single-phase x-ray unit recti er operation o a three-phase x-ray unit timer accuracy o a single-phase x-ray unit timer accuracy o a three-phase x-ray unit

44. T e best projection to demonstrate the articular sur aces o the emoropatellar articulation is the (A) (B) (C) (D)

359

AP knee PA knee tangential (“sunrise”) projection tunnel view

Figure 7-6.

360

7: Practice Test 2

49. T e ollowing procedures demonstrate renal unction 1. IVU 2. excretory urography 3. retrograde urography (A) (B) (C) (D) 50.

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

o eject a K-shell electron rom a tungsten atom, the incoming electron must have an energy o at least (A) (B) (C) (D)

60 keV 70 keV 80 keV 90 keV

51. T e sternoclavicular joints will be best demonstrated in which o the ollowing positions? (A) (B) (C) (D)

Apical lordotic Anterior oblique Lateral Weight-bearing

52. Which o the ollowing image intensi er modes will result in the lowest patient dose? (A) (B) (C) (D)

a 25 inch mode a 17 inch mode a 12 inch mode Diameter does not a ect patient dose

53. T e most requent site o hospital-acquired in ection is the (A) (B) (C) (D)

urinary tract blood respiratory tract digestive tract

54. Which o the ollowing statements is (are) true regarding the control dosimeter that accompanies each shipment o personal radiation monitors? 1. It should be stored away rom all radiation sources. 2. It should be stored in the main work area. 3. It should be used to replace an employee’s lost monitor. (A) (B) (C) (D)

1 only 2 only 1 and 3 only 2 and 3 only

55. Continuous rotation o the C x-ray tube and detector array, with simultaneous movement o the C couch, has been accomplished through implementation o (A) (B) (C) (D)

additional cables slip rings multiple rows o detectors electron beam C

56. T e two types o cells in the body are (A) (B) (C) (D)

connective and nerve genetic and connective somatic and nerve somatic and genetic

57. A satis actory radiograph was made without a grid using a 72-inch SID and 8 mAs. I the distance is changed to 40 inches and a 12:1 ratio grid is added, what should be the new milliampere-seconds value? (A) (B) (C) (D)

9.5 mAs 12 mAs 21 mAs 26 mAs

Questions: 49–64

58. Which o the ollowing involve(s) intentional misconduct? 1. Invasion o privacy 2. False imprisonment 3. Patient sustaining injury rom a all while le unattended (A) (B) (C) (D)

1 only 3 only 1 and 2 only 2 and 3 only

59. T e brightness level o the depends on

62. T e submentovertical (SMV) oblique axial projection o the zygomatic arches requires that the skull be rotated (A) (B) (C) (D)

15 degrees toward the a ected side 15 degrees away rom the a ected side 45 degrees toward the a ected side 45 degrees away rom the a ected side

63. T e image o the pelvis shown in Figure 7-7 is unacceptable because o uoroscopic image

1. milliamperage 2. kilovoltage 3. patient thickness (A) (B) (C) (D)

361

(A) (B) (C) (D)

motion inadequate penetration scattered radiation og excessive receptor exposure

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

60. Which o the ollowing contribute to image contrast in SF/analog imaging? 1. issue density 2. Pathology 3. Muscle development (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

61. In 1906, Bergonié and ribondeau theorized that undi erentiated cells are highly radiosensitive. Which o the ollowing is (are) characteristic(s) o undi erentiated cells?

Figure 7-7. From the American College o Radiology Learning File. Courtesy o the ACR.

64. T e e ect that di erential absorption has on radiographic contrast o a high subject contrast part can be minimized by

1. Young cells 2. Highly mitotic cells 3. Precursor cells

1. using a compensating lter 2. using high kilovoltage technical actors 3. increased collimation

(A) (B) (C) (D)

(A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

362

7: Practice Test 2

Figure 7-8. Courtesy o Stam ord Hospital, Department o Radiology.

65. T e chest radiograph shown in Figure 7-8 demonstrates (A) (B) (C) (D)

breathing motion aliasing arti act double exposure o -level grid cuto

66. Which o the ollowing is most likely to occur as a result o using a 30-inch SID with a 14 × 17 inch IR to image a airly homogeneous structure? (A) Production o quantum mottle (B) Receptor exposure variation between opposite ends o the IR (C) Production o scatter radiation og (D) Excessively short-scale contrast

67. Which o the ollowing is (are) correct regarding care o protective leaded apparel? 1. Lead aprons should be uoroscoped yearly to check or cracks. 2. Lead gloves should be uoroscoped yearly to check or cracks. 3. Lead aprons should be hung on appropriate racks when not in use. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

68. An exposure was made using 300 mA and 50 ms. I the exposure time is changed to 22 ms, which o the ollowing milliamperage selections would most closely approximate the original receptor exposure? (A) (B) (C) (D)

300 mA 400 mA 600 mA 700 mA

Questions: 65–78

69. Which o the ollowing is (are) considered long-term somatic e ect(s) o exposure to ionizing radiation? 1. Li e-span shortening 2. Carcinogenesis 3. Cataractogenesis (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

70. Advantages o direct digital radiography (DR) over computed radiography (CR) include 1. DR is less expensive 2. DR has immediate readout 3. IPs are not needed or DR (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

71. T e collimator light and actual irradiated area must be accurate to within (A) (B) (C) (D)

2% o the SID 5% o the SID 10% o the SID 15% o the SID

72. All the ollowing statements regarding the bony thorax are true except (A) the rst seven pairs o ribs are re erred to as vertebrosternal, or true, ribs (B) the only articulation between the thorax and the upper extremity is the sternoclavicular joint (C) the gladiolus is the upper part o the sternum and is quadrilateral in shape (D) the anterior ends o the ribs are about 4 inches below the level o the vertebral ends 73. Several types o exposure timers may be ound on x-ray equipment. Which o the ollowing types o timers is the most accurate? (A) Synchronous (B) Impulse (C) Electronic (D) rans ormer

363

74. T e late e ects o radiation are considered to 1. have no threshold dose 2. be directly related to dose 3. occur within hours o exposure (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

75. T e lesser tubercle o the humerus will be visualized in pro le in the (A) (B) (C) (D)

AP shoulder external rotation radiograph AP shoulder internal rotation radiograph AP elbow radiograph Lateral elbow radiograph

76. Which one o the ollowing is (are) used to control the production o scattered radiation? 1. Collimators 2. Optimal kV 3. Use o grids (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

77. With the patient in an erect 45-degree LPO and the CR directed 2 inches medial and 2 inches lateral to the upper outer border o the shoulder, which o the ollowing will be visualized to best advantage? (A) (B) (C) (D)

Coronoid process ree o superimposition Coracoid process ree o superimposition Glenoid cavity in pro le Greater tubercle in pro le

78. Which o the ollowing groups o technical actors would deliver the lowest patient dose? (A) (B) (C) (D)

2.5 mAs, 100 kVp 5 mAs, 90 kVp 5 mAs, 70 kVp 10 mAs, 80 kVp

364

7: Practice Test 2

79. Which o the ollowing is (are) included in wholebody dose equivalents? 1. Gonads 2. Lens 3. Extremities (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

83. Which section o the automatic processor shown in Figure 7-9 acts upon exposed silver grains? (A) (B) (C) (D)

Section 1 Section 2 Section 3 Section 4

80. Which o the ollowing is (are) valid evaluation criteria or a lateral projection o the orearm? 1. T e radius and the ulna should be superimposed distally. 2. T e coronoid process and the radial head should be partially superimposed. 3. T e humeral epicondyles should be superimposed. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

81. I a quantity o radiation is delivered to a body over a short period o time, its e ect (A) will be greater than i it were delivered over a long period o time (B) depends solely on the distance actor (C) has no relation to how it is delivered in time (D) depends solely on the radiation quantity 82. According to the line- ocus principle, an anode with a small angle provides 1. improved recorded detail 2. improved heat capacity 3. less heel e ect (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

1

2

3

4

Figure 7-9.

84. Which o the ollowing expresses the gonadal dose that, i received by every member o the population, would be expected to produce the same total genetic e ect on that population as the actual doses received by each o the individuals? (A) (B) (C) (D)

Lethal dose Maximum permissible dose Somatically signi cant dose Genetically signi cant dose

85. A patient with an upper respiratory tract in ection is transported to the radiology department or a chest examination. Who should be masked? 1. echnologist 2. ransporter 3. Patient (A) (B) (C) (D)

1 only 1 and 2 only 3 only 1, 2, and 3

Questions: 79–93

86. T e kV settings on radiographic equipment must be tested annually and must be accurate to within (A) (B) (C) (D)

(A) (B) (C) (D)

89. T e reduction in x-ray photon intensity as the photon passes through a material is termed

+ /− 2 kV + /− 4 kV + /− 6 kV + /− 8 kV

87. T e radiograph shown in Figure 7-10 exhibits a loss o receptor exposure as a result o x-ray tube angulation across grid lines exceeding the ocusing distance incorrect grid placement insuf cient SID

365

(A) (B) (C) (D) 90.

anode heel e ect grid cuto attenuation divergence

o demonstrate the glenoid ossa in pro le, the patient is positioned (A) (B) (C) (D)

45 degrees oblique, a 45 degrees oblique, a 25 degrees oblique, a 25 degrees oblique, a

ected side up ected side down ected side up ected side down

91. Which o the ollowing groups o technical actors will produce the shortest scale o contrast? (A) (B) (C) (D)

200 mA, 0.25 s, 70 kVp, 12:1 grid 500 mA, 0.10 s, 90 kVp, 8:1 grid 400 mA, 0.125 s, 80 kVp, 12:1 grid 300 mA, 0.16 s, 70 kVp, 8:1 grid

92. In which o the ollowing procedures is quiet, shallow breathing recommended during the exposure to obliterate prominent pulmonary vascular markings? 1. RAO sternum 2. Lateral thoracic spine 3. AP scapula (A) (B) (C) (D) Figure 7-10. Courtesy o Stam ord Hospital, Department o Radiology.

88. Which o the ollowing wave orms has the lowest percentage voltage ripple? (A) (B) (C) (D)

Single-phase T ree-phase, six-pulse T ree-phase, 12-pulse High- requency

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

93. How are LE and biologic response related? (A) (B) (C) (D)

T T T T

ey are inversely related. ey are directly related. ey are related in a reciprocal ashion. ey are unrelated.

366

7: Practice Test 2

94. An increase in the kilovoltage applied to the x-ray tube increases the 1

1. percentage o high-energy photons produced 2. exposure rate 3. patient absorption (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

2 3 4

95. Which o the ollowing is/are associated with magni cation uoroscopy?

5

1. Higher patient dose than nonmagni cation uoroscopy. 2. Higher voltage to the ocusing lenses. 3. Image intensi er ocal point closer to the input phosphor. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

96. Replacing 200-speed intensi ying screens with 400-speed screens in SF/analog imaging will 1. require the exposure to be cut in hal 2. enable the radiographer to decrease the exposure time 3. increase the production o scattered radiation (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

97. T e structure indicated by the number 3 in Figure 7-11 is the (A) (B) (C) (D)

ascending colon descending colon transverse colon sigmoid colon

Figure 7-11. Courtesy o Stam ord Hospital, Department o Radiology.

98. T e structure indicated by the number 1 in Figure 7-11 is the (A) (B) (C) (D)

le colic exure right colic exure transverse colon sigmoid colon

99. Which o the ollowing exposures would most likely deliver the greatest dose to the thyroid? (A) (B) (C) (D)

AP skull PA skull PA esophagus PA chest

100. Which o the ollowing conditions require(s) a decrease in technical actors? 1. Emphysema 2. Osteomalacia 3. Atelectasis (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Questions: 94–110

101. Which o the ollowing cell types is the least radiosensitive? (A) (B) (C) (D)

Myelocytes Myocytes Megakaryocytes Erythroblasts

102. Characteristic(s) o a 16:1 grid include 1. It absorbs more use ul radiation than an 8:1 grid. 2. It has more centering latitude than an 8:1 grid. 3. It is used with higher-kilovoltage exposures than an 8:1 grid. (A) (B) (C) (D)

1 only 1 and 3 only 2 and 3 only 1, 2, and 3

103. A SF/analog exposure was made at 40-in SID using 5 mAs and 105 kVp with an 8:1 grid. In an e ort to improve radiographic contrast, the image is repeated using a 12:1 grid and 90 kV. Which o the ollowing exposure times will be most appropriate, using 400 mA, to maintain the original receptor exposure? (A) (B) (C) (D)

0.01 s 0.03 s 0.1 s 0.3 s

104. All the ollowing statements regarding three-phase current are true except (A) three-phase current is constant-potential direct current (B) three-phase equipment produces more x-rays per milliampere-second than single-phase equipment (C) three-phase equipment produces higher– average-energy x-rays than single-phase equipment (D) the three-phase wave orm has less ripple than the single-phase wave orm

367

105. T e pyloric canal and duodenal bulb are best demonstrated during an upper GI series in which o the ollowing positions? (A) (B) (C) (D)

RAO Le lateral Recumbent PA Recumbent AP

106. T e most common cause o x-ray tube ailure is (A) (B) (C) (D)

a cracked anode a pitted anode vaporized tungsten on glass envelope insuf cient heat production

107. I a radiograph were made o an average-size knee using automatic exposure control (AEC) and all three photocells were selected, the resulting radiograph would demonstrate (A) (B) (C) (D)

excessive receptor exposure insuf cient receptor exposure poor detail adequate exposure

108. Which o the ollowing statements regarding SNR is most accurate? (A) (B) (C) (D)

SNR increases as mAs increases Low SNR is desirable Low SNR improves resolution SNR increases as kV decreases

109. In which o the ollowing examinations would an IR ront with very low absorption properties be especially desirable? (A) (B) (C) (D)

Extremity radiography Abdominal radiography Mammography Angiography

110. T e regular measurement and evaluation o radiographic equipment components and their per ormance is most accurately termed (A) (B) (C) (D)

postprocessing quality assurance quality control quality congruence

368

7: Practice Test 2

111. T e radiograph in Figure 7-12 could be improved in which o the ollowing ways? (A) T o (B) T o (C) T (D) T

e MSP should be 45 degrees to the plane the IR. e MSP should be 90 degrees to the plane the IR. e chin should be elevated slightly. e head should be exed slightly. Figure 7-13.

114. What acronym is used to help rescuers remember the correct CPR step sequence? (A) (B) (C) (D)

BLS ACB CAB SLB

115. T e decision as to whether to deliver ionic or nonionic contrast medium should include a preliminary patient history including, but not limited to 1. patient age 2. history o respiratory disease 3. history o cardiac disease (A) (B) (C) (D) Figure 7-12. Courtesy o Stam ord Hospital, Department o Radiology.

112. What is the anatomic structure indicated by the number 3 in the radiograph in Figure 7-12? (A) Spinous process (B) ransverse process (C) Pedicle (D) Intervertebral oramen 113. With the patient positioned as shown in Figure 7-13, how should the CR be directed to best demonstrate the intercondyloid ossa? (A) (B) (C) (D)

Perpendicular to the popliteal depression. 40 degrees caudad to the popliteal depression. Perpendicular to the long axis o the emur. 40 degrees cephalad to the popliteal depression.

1 and 2 1 and 3 2 and 3 1, 2, and 3

116. Dorsal decubitus projections o the chest are used to evaluate small amounts o 1. uid in the posterior chest 2. air in the posterior chest 3. uid in the anterior chest (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

117. At what requency must the radiographic equipment be checked or linearity and reproducibility? (A) (B) (C) (D)

Annually Biannually Semiannually Quarterly

Questions: 111–124

118. Which o the labeled bones in Figure 7-14 identies the tarsal cuboid? (A) (B) (C) (D)

121. Features o digital uoroscopy (DF) that contribute to patient dose reduction include 1. last image hold 2. pulsed exposure 3. longer procedure times

Number 2 Number 3 Number 6 Number 7

(A) (B) (C) (D)

7 2

6

5

3

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

122. Sterile technique is required when contrast agents are administered

8

1

(A) (B) (C) (D)

Figure 7-14.

119. What does the number 1 in Figure 7-14 identi y? (A) Medial malleolus (B) Lateral malleolus (C) Medial cunei orm (D) alus

through a nasogastric tube intrathecally rectally orally

123. Which o the ollowing groups o technical actors would be most appropriate or a sthenic adult IVU? (A) (B) (C) (D)

4

6 mAs, 72 kVp 3 mAs, 82 kVp 1.5 mAs, 94 kVp 3 mAs, 92 kVp

124. Which o the our baselines illustrated in Figure 7-15 should be used or a lateral projection o acial bones? (A) (B) (C) (D)

Baseline 1 Baseline 2 Baseline 3 Baseline 4

1 2

120. Excretory urography usually includes a postmicturition radiograph o the bladder. T is is done to demonstrate

3

1. tumor masses 2. residual urine 3. prostatic enlargement (A) (B) (C) (D)

369

2 only 1 and 3 only 2 and 3 only 1, 2, and 3

4

Figure 7-15.

370

7: Practice Test 2

125. Which o the ollowing statements is (are) true regarding the radiograph shown in Figure 7-16? 1. T e part is rotated. 2. Pneumothorax is present. 3. Adequate inspiration is demonstrated. (A) (B) (C) (D)

1 only 2 only 1 and 2 only 1, 2, and 3

127. While measuring blood pressure, the rst pulse that is heard is recorded as the (A) (B) (C) (D)

diastolic pressure systolic pressure venous pressure valvular pressure

128. T e AP oblique projection (Grashey method) o the glenoid ossa requires that the body is rotated (A) (B) (C) (D)

35 to 45 degrees toward the una ected side 35 to 45 degrees toward the a ected side 15 to 20 degrees toward the a ected side 15 to 20 degrees toward the una ected side

129. When the collimated eld must extend past the edge o the body, allowing primary radiation to strike the tabletop, as in a lateral lumbar spine radiograph, what may be done to prevent excessive receptor exposure owing to undercutting? (A) (B) (C) (D)

Reduce the milliampere-seconds. Reduce the kilovoltage. Use a shorter SID. Use lead rubber to absorb tabletop primary radiation.

130. What is the name o the plane indicated by the number 1 in Figure 7-17?

Figure 7-16.

126. T e radiation dose to a part depends on which o the ollowing? 1. ype o tissue interaction(s) 2. Quantity o radiation 3. Biologic di erences (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

(A) Midcoronal plane (B) Midsagittal plane (C) ransverse plane (D) Horizontal plane

Questions: 125–134

371

1

2

3

Pos t e rio r An te r

io r

Figure 7-17.

131. Which o the ollowing is the most likely site or a lumbar puncture? (A) (B) (C) (D)

S1–2 L3–4 L1–2 C6–7

132. T e in ection streptococcal pharyngitis (“strep throat”) is caused by a (A) (B) (C) (D)

133. Di erences between body habitus types are likely to a ect all the ollowing except

virus ungus protozoon bacterium

(A) (B) (C) (D) 134.

the size and shape o an organ the position o an organ the position o the diaphragm the degree o bone porosity

echnical actors o 80 kVp and 8 mAs are used or a particular nongrid exposure. What should be the new milliampere-seconds value i an 8:1 grid is added? (A) (B) (C) (D)

16 mAs 24 mAs 32 mAs 40 mAs

372

7: Practice Test 2 1

2

3

4

Figure 7-18. Reproduced with permission rom Saia DA. LANGERadiography Review Flashcards. New York: McGraw-Hill, 2015.

135. Which o the illustrations in Figure 7-18 most closely portrays the hypersthenic body type? (A) (B) (C) (D)

Illustration number one Illustration number two Illustration number three Illustration number our

136. Which o the ollowing unctions to protect the x-ray tube and the patient rom overexposure in the event that the phototimer ails to terminate an exposure? (A) (B) (C) (D)

Circuit breaker Fuse Backup timer Rheostat

137. Which o the ollowing positions can be used to e ectively demonstrate the le colic exure during radiographic examination o the large bowel? 1. RAO 2. LAO 3. RPO (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 2 and 3 only

138. Which cholangiographic procedure uses an indwelling drainage tube or contrast medium administration? (A) Endoscopic retrograde cholangiographic pancreatography (ERCP). (B) Operative cholangiography. (C) -tube cholangiography. (D) Percutaneous transhepatic cholangiography.

139. Maslow’s hierarchy o basic human needs includes which o the ollowing? 1. Sel -esteem 2. Love and belongingness 3. Death with dignity (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

140. Which o the ollowing combinations would deliver the least amount o heat to the anode o a three-phase, 12-pulse x-ray unit? (A) (B) (C) (D)

400 mA, 0.12 s, 90 kVp 300 mA, 1⁄2 s, 70 kVp 500 mA, 1⁄30 s, 85 kVp 700 mA, 0.06 s, 120 kVp

141. Which o the ollowing technical changes is most likely to permit the greatest reduction in patient dose? (A) Increasing the mAs by hal and decreasing the kVp by 15%. (B) Increasing kilovoltage by 15% and cutting the milliampere-seconds value in hal . (C) Changing collimation rom 10 × 12 to 14 × 17. (D) Changing rom an 8:1 grid technique to nongrid. 142. T e trapezium is identi ed in Figure 7-19 as (A) (B) (C) (D)

Number 3 Number 4 Number 5 Number 6

Questions: 135–150

373

146. Which o the ollowing is (are) demonstrated in the lateral projection o the cervical spine? 1. Intervertebral joints 2. Apophyseal joints 3. Intervertebral oramina (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

147. Contaminated needles are disposed o in special containers in which o the ollowing ways?

Figure 7-19.

143. T e major di erence between excretory and retrograde urography is that (A) they each require a di erent type o contrast agent (B) intravenous studies require more images (C) retrograde studies do not demonstrate unction (D) more contrast medium–induced adverse reactions occur in retrograde studies 144. In myelography, the contrast medium generally is injected into the (A) cisterna magna (B) individual intervertebral disks (C) subarachnoid space between the rst and second vertebrae (D) subarachnoid space between the third and ourth lumbar vertebrae 145. Body substances and uids that are considered in ectious or potentially in ectious include 1. eces 2. breast milk 3. wound drainage (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

(A) Recap the needle, remove syringe, dispose o . (B) Do not recap needle, remove rom syringe, dispose o . (C) Recap the needle, dispose o entire syringe. (D) Do not recap needle, dispose o entire syringe. 148. I the entrance dose or a particular radiograph is 320 mR, the radiation exposure at 1 m rom the patient will be approximately (A) (B) (C) (D)

32 mR 3.2 mR 0.32 mR 0.032 mR

149. What eature is used to display RIS in ormation on current patients? (A) (B) (C) (D)

HIS Modality work list PACS DICOM

150. Which o the ollowing would be the sa est interval o time or a ertile woman to undergo abdominal radiography without signi cant concern or irradiating a recently ertilized ovum? (A) T e rst 10 days ollowing the cessation o menstruation. (B) T e rst 10 days ollowing the onset o menstruation. (C) T e 10 days preceding the onset o menstruation. (D) About 14 days be ore menstruation.

374

7: Practice Test 2

151. What is the anatomic structure indicated by number 1 in the radiograph shown in Figure 7-20? (A) (B) (C) (D)

Mandibular angle Coronoid process Zygomatic arch Maxillary sinus

154. Greater latitude is available to the radiographer in SF/analog imaging when using 1. high-kilovoltage actors 2. a small ocal spot 3. a high-ratio grid (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

155. With which o the ollowing does the lateral extremity o the clavicle articulate? (A) (B) (C) (D)

Manubrium Coracoid process Coronoid process Acromion process

156. With the patient supine, the le side o the pelvis elevated 25 degrees, and the CR entering 1 in medial to the le anterosuperior iliac spine (ASIS), which o the ollowing is demonstrated?

Figure 7-20. Courtesy o Stam ord Hospital, Department o Radiology.

152. What is the anatomic structure indicated by number 3 in the radiograph in Figure 7-20? (A) (B) (C) (D)

Mandibular angle Coronoid process Zygomatic arch Maxillary sinus

153. Esophageal varices are best demonstrated in which o the ollowing positions? (A) (B) (C) (D)

Erect Recumbent Fowler Sims

(A) (B) (C) (D)

Le sacroiliac joint Le ilium Right sacroiliac joint Right ilium

157. Double- ocus x-ray tubes have two 1. ocal spots 2. laments 3. anodes (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 2 and 3 only

158. What is the anatomic structure indicated by number 1 in the radiograph shown in Figure 7-21? (A) Superior articular process (B) In erior articular process (C) ransverse process (D) Lamina

Questions: 151–163

375

160. Which o the ollowing statements is (are) true regarding the lateral projection o the lumbar spine? 1. T e MSP is parallel to the tabletop. 2. T e vertebral oramina are well visualized. 3. T e pedicles are well visualized. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

161. I a patient received 4,500 mrad during a 6-minute uoroscopic examination, what was the dose rate? (A) (B) (C) (D)

0.75 rad/min 2.7 rad/min 7.5 rad/min 27 rad/h

162. Which o the ollowing is (are) essential to high-quality mammographic examinations? 1. Small ocal-spot x-ray tube 2. Short scale contrast 3. Use o a compression device (A) (B) (C) (D) Figure 7-21. Courtesy o Stam ord Hospital, Department o Radiology.

159. What is the anatomic structure indicated by number 3 in the radiograph in Figure 7-21? (A) (B) (C) (D)

Superior articular process In erior articular process Pedicle Lamina

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

163. An exposure was made using a SF/analog system, at a 36-in SID using 12 mAs and 75 kVp with a 400speed imaging system and an 8:1 grid. A second image is requested with improved recorded detail. Which o the ollowing groups o technical actors will best accomplish this task? (A) 15 mAs, 12:1 grid, 75 kVp, 400 speed system, 36-inch SID. (B) 15 mAs, 12:1 grid, 75 kVp, 400 speed system, 40-inch SID. (C) 30 mAs, 12:1 grid, 75 kVp, 200 speed system, 40-inch SID. (D) 12 mAs, 8:1 grid, 86 kVp, 200 speed system, 36-inch SID.

376

7: Practice Test 2

164. What is the anatomic structure indicated by the number 10 in Figure 7-22? (A) Coracoid process (B) Coronoid process (C) rochlear notch (D) Radial notch

5

166. Which o the ollowing statements is (are) true regarding the PA axial projection o the paranasal sinuses? 1. T e CR is directed caudally to the orbitomeatal line (OML). 2. T e petrous pyramids are projected into the lower third o the orbits. 3. T e rontal sinuses are visualized. (A) (B) (C) (D)

4 3

6

2 7

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

167. What percentage o x-ray attenuation does a 0.5-mm lead equivalent apron at 75 kVp provide?

1

(A) (B) (C) (D)

8

51% 66% 75% 88%

12

168. An illness o unknown or obscure cause is said to be (A) (B) (C) (D) 169. 9 10 11

Figure 7-22.

165. Which o the ollowing correctly identi es the head o the ulna in the illustration in Figure 7-22? (A) (B) (C) (D)

Number 3 Number 4 Number 5 Number 9

systemic epidemic idiopathic pathogenic

o better demonstrate the interphalangeal joints o the toes, which o the ollowing procedures may be employed? 1. Angle the CR 15 degrees caudad. 2. Angle the CR 15 degrees cephalad. 3. Place a sponge wedge under the oot with the toes elevated 15 degrees. (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 2 and 3 only

170. T e most commonly used method o low- ow oxygen delivery is the (A) (B) (C) (D)

oxygen mask nasal cannula respirator oxyhood

Questions: 164–180

171. T e emoral neck can be located (A) parallel to the emoral sha (B) perpendicular to the emoral sha (C) perpendicular to a line drawn rom the ASIS to the pubic symphysis (D) perpendicular to a line rom the iliac crest to the pubic symphysis 172. In what order should the ollowing examinations be scheduled? 1. Upper GI 2. Intravenous pyelogram (IVP) 3. Barium enema (BE) (A) (B) (C) (D)

3, 1, 2 1, 3, 2 2, 1, 3 2, 3, 1

173. Improper support o a patient’s ractured lower leg (tibia/ bula) while per orming radiography could result in 1. movement o racture ragments 2. tearing o so tissue, nerves, and blood vessels 3. initiation o muscle spasm (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

174. Personal radiation monitor reports must include which o the ollowing in ormation? 1. Dose equivalents or report period 2. Dosimeter type 3. Radiation quality (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

175. T e intertrochanteric crest is located on the (A) (B) (C) (D)

proximal posterior emur proximal anterior emur distal posterior emur distal anterior emur

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176. T e ethical principle that aspires to, above all, do no harm describes (A) delity (B) veracity (C) nonmale cence (D) bene cence 177. A radiographer would be in violation o the American Registry o Radiologic echnologists (ARR ) Code o Ethics or the Pro ession o Radiologic echnology or all o the ollowing except (A)

ailing to wear a lead apron when per orming mobile radiography (B) ailing to participate in continuing education (C) communicating in ormation regarding suspected child abuse to the re erring physician (D) re using to participate in new and innovative technical procedures 178. Hospitals and other healthcare providers must ensure patient con dentiality in compliance with which o the ollowing legislation? (A) (B) (C) (D)

MQSA MRSA HIPAA HIPPA

179. T e term dysplasia re ers to (A) (B) (C) (D)

dif culty speaking abnormal development o tissue malposition dif cult or pain ul breathing

180. T e ethical principle that re ers to bringing about good, or bene ting others, is called (A) delity (B) veracity (C) nonmale cence (D) bene cence

378

7: Practice Test 2

181. A technique chart should include which o the ollowing in ormation? 1. Recommended SID 2. Grid ratio 3. CR angulation (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

182. What is the established etal dose-limit guideline or pregnant radiographers during the entire gestation period? (A) (B) (C) (D)

0.1 rem 0.5 rem 5.0 rem 10 rem

183. T e acquired immune de ciency syndrome (AIDS) virus may be transmitted 1. by sharing contaminated needles 2. rom mother to child during birth 3. by intimate contact with body uids (A) (B) (C) (D)

1 only 1 and 2 only 1 and 3 only 1, 2, and 3

184. Which o the ollowing vessels does not carry oxygenated blood? (A) (B) (C) (D)

Pulmonary vein Pulmonary artery Coronary artery Chordae tendineae

185. Which o the ollowing are considered most radiosensitive? (A) (B) (C) (D)

Lymphocytes Ova Neurons Myocytes

186. It is recommended that a thermoluminescent dosimeter ( LD) or OSL be worn (A) (B) (C) (D)

under the lead apron at waist level outside the lead apron at waist level under the lead apron at collar level outside the lead apron at collar level

187. Which o the ollowing is/are associated with magni cation uoroscopy? 1. Increased mA. 2. Smaller portion o the input phosphor is used. 3. Image intensi er ocal point moves closer to the output phosphor. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

188. Shape distortion is in uenced by the relationship between the 1. x-ray tube and the part to be imaged 2. body part to be imaged and the IR 3. IR and the x-ray tube (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

189. Linear energy trans er (LE ) may be best described as (A) the amount o energy delivered per distance traveled in tissue (B) the unit o absorbed dose (C) radiation equivalent man (D) radiation absorbed dose 190. Which o the ollowing statements is (are) correct with respect to postoperative cholangiography? 1. A -tube is in place in the common bile duct. 2. Water-soluble contrast material is injected. 3. T e patency o biliary ducts is evaluated. (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

Questions: 181–200

191. Which o the ollowing is a ast-acting vasodilator used to lower blood pressure and relieve the pain o angina pectoris? (A) (B) (C) (D)

Digitalis Dilantin Nitroglycerin Cimetidine ( agamet)

192. In SF/analog imaging, an increase in kilovoltage with appropriate compensation o milliampereseconds will result in 1. increased exposure latitude 2. higher contrast 3. increased receptor exposure (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1 and 3 only

193. T e annual dose limit or occupationally exposed individuals is valid or (A) (B) (C) (D)

alpha, beta, and x-radiations x- and gamma radiations only beta, x-, and gamma radiations all ionizing radiations

194. T e quantity that is re ective o dose and the volume o tissue exposed is (A) (B) (C) (D)

R in air absorbed dose dose area product entrance skin exposure

195. When examining a patient whose elbow is in partial exion (A) the AP projection requires two separate positions and exposures (B) the AP projection is made through the partially exed elbow, resting on the olecranon process, CR perpendicular to IR (C) the AP projection is made through the partially exed elbow, resting on the olecranon process, CR parallel to the humerus (D) the AP projection is eliminated rom the routine

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196. Recorded detail is directly related to 1. SID 2. tube current 3. ocal-spot size (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

197. T e Centers or Disease Control and Prevention (CDC) suggests that healthcare workers protect themselves and their patients rom blood and body uid contamination by using (A) (B) (C) (D)

strict isolation precautions standard precautions respiratory precautions sterilization

198. X-ray tube li e may be extended by 1. using high milliampere-second, low kilovoltage technical actors 2. avoiding lengthy anode rotation 3. avoiding exposures to a cold anode (A) (B) (C) (D)

1 only 1 and 2 only 2 and 3 only 1, 2, and 3

199. Which o the ollowing unctions to increase the milliamperage? (A) (B) (C) (D)

Increasing the speed o anode rotation. Increasing the trans ormer turns ratio. Using three-phase recti cation. Increasing the heat o the lament.

200. Which o the ollowing radiographic examinations require(s) the patient to be NPO 8 to 10 hours prior to examination or proper patient preparation? 1. Abdominal survey 2. Upper GI series 3. BE (A) (B) (C) (D)

1 and 2 only 1 and 3 only 2 and 3 only 1, 2, and 3

Answers and Explanations

1. (C) An antihistamine is used to relieve allergic e ects. Benadryl (diphenhydramine hydrochloride) is an example o an antihistamine that is o en on hand in radiology departments in the event o a minor reaction to contrast media. An antipyretic is used to reduce ever. ylenol (acetaminophen) is an example o an antipyretic. Ipecac is a medication used to induce vomiting and is classi ed as an emetic. T is is easy to remember i you think o what an emesis basin is or. A diuretic is a medication that stimulates the production o urine. Lasix ( urosemide) is an example o a diuretic.

bowel ganglion cells—usually in the rectosigmoid area but occasionally more extensively. Hirschsprung disease is the most common cause o lower GI obstruction in neonates and is treated surgically by excision o the a ected area ollowed by reanastomosis with the normal, healthy bowel. Hirschsprung disease is diagnosed by BE or, in mild cares, by rectal biopsy. Intussusception is “telescoping” o the bowel, causing (mechanical) obstruction. Volvulus is twisting o the bowel on itsel causing (mechanical) obstruction. Pyloric stenosis is a condition o the upper GI tract.

2. (C) A histogram is a graph usually having several peaks and valleys representing the pixel values/ absorbing properties o the various tissues, and so on that make up the imaged part. T ese various attenuators include such things as bone, muscle, air, contrast agents, oreign bodies, and pathology. T e various pixel values, then, represent image contrast. I the histogram has a rather at “tail,” this represents underexposed areas at the periphery o the image, which can skew the overall histogram analysis. T e radiographer selects the particular processing algorithm on the computer/control panel that corresponds to the anatomic part and projection being per ormed. DICOM (Digital Imaging and Communications in Medicine) re ers to the standard or communication between PACS and HIS/ RIS systems. Windowing re ers to the radiographer’s postprocessing adjustment o contrast and brightness (at the workstation).

4. (B) Contrast media having high atomic number are re erred to as radiopaque because x-ray photons have dif culty penetrating these dense materials. Radiopaque contrast agents appear white on the x-ray image because many x-ray photons have been absorbed by these materials (e.g., barium, iodine). T ese are re erred to positive contrast agents—composed o dense (i.e., high atomic number) material through which x-rays will not pass easily. Radiolucent contrast agents appear black on the nished image because x-ray photons pass through easily. An example o a radiolucent contrast agent is air.

3. (C) Hirschsprung disease, or congenital megacolon, is caused by the absence o some or all o the

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5. (A) It is our ethical responsibility to minimize radiation dose to patients. X-rays produced at the target make up a heterogeneous primary beam. T ere are many “so ” (low-energy) photons that, i not removed, would contribute only to greater patient dose. T ey are too weak to penetrate the patient and expose the IR. T ese so x-rays penetrate only a small thickness o tissue be ore being absorbed.

Answers: 1–12

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6. (A) Proper body mechanics includes a wide base o support. T e base o support is the portion o the body that is in contact with the oor or some other horizontal plane. T e center o gravity is the midpoint o the pelvis or lower abdomen, depending on body build. T e line o gravity is the abstract line passing vertically through the center o gravity. Proper body mechanics can help to prevent pain ul back injuries by making pro cient use o the muscles in the arms and legs. 7. (D) T e knee is ormed by the proximal tibia, the patella, and the distal emur, which articulate to orm the emorotibial and emoropatellar joints. T e distal posterior emur presents two large medial and lateral condyles separated by the deep intercondyloid ossa. Because the medial emoral condyle is urther rom the IR, it is magni ed and will obscure the emorotibial joint space, as seen in the gure. I the CR is angled about 5 degrees cephalad, the medial emoral condyle will be projected superiorly and superimposed on the lateral emoral condyle, thus opening the joint space. T e patient should lie on the a ected side with the patella perpendicular to the tabletop and the knee exed 20 to 30 degrees. Rotating the part orward or backward will a ect visualization o the emoropatellar joint. 8. (C) Because muscle and nerve tissues per orm speci c unctions and do not divide, they are relatively insensitive to ionizing radiation exposure. Epithelial cells cover the outer sur ace o the body; they also line body cavities and tubes and passageways leading to the exterior. T ey contain very little intercellular substance and are devoid o blood vessels. Because epithelial cells constantly regenerate through mitosis they are very radiosensitive. 9. (D) T e x-ray tube anode is designed according to the line- ocus principle, that is, with the ocal track beveled (Fig. 7-23). T is allows a larger actual ocal spot to project a smaller e ective ocal spot, resulting in improved recorded detail with less blur. However, because o the target angle, penumbral blur varies along the longitudinal tube axis, being greater at the cathode end o the image and less at the anode end o the image. T ere ore, better detail will be appreciated using small ocal spots at the anode end o the x-ray beam and at longer SIDs.

Blur

Blur

Figure 7-23.

10. (C) T ree dose–response (dose–e ect) curves are illustrated, representing the body’s response to ionizing radiation exposure. Dose is indicated by the horizontal axis (increasing to the right); response is indicated by the vertical axis (increasing upward). wo o the curves (numbers 1 and 3) are linear; that is, response is directly related to dose. Curve 2 is not a straight line and is, there ore, nonlinear. Curves 2 and 3 show that a particular dose (threshold quantity) o radiation is required be ore any e ect will occur; there ore, curve 2 is nonlinear threshold, and curve 3 is linear threshold. Curve 1, however, shows that any dose o radiation (theoretically, even a single x-ray photon; that is, there is no threshold) can result in a particular biologic e ect; there ore, it is linear nonthreshold. 11. (A) T e scaphoid can be dif cult to image because its curved shape lends itsel to oreshortening and sel -superimposition. T e lateral carpals, especially the scaphoid, are well demonstrated in the PA oblique projection. T e ulnar deviation maneuver helps to overcome the scaphoid’s sel -superimposition. T e scaphoid may also be demonstrated with less oreshortening with the wrist PA and elevated 20 degrees. T e CR is directed perpendicular to the carpal scaphoid. T e medial carpals, especially the pisi orm, are well demonstrated in the AP oblique projection with the radial deviation maneuver. 12. (D) A patient who has been recumbent or some period o time and gets up quickly may su er rom light-headedness or eel aint. T is is re erred to as

382

7: Practice Test 2

orthostatic hypertension. It is best to have patients sit up and dangle their eet rom the table or a moment while being supported and then assist them o the table. Patients also will eel better emotionally i they are not rushed or treated like they are on an assembly line. Always assist patients on and o o the radiographic table. Even healthy, young outpatients can injure themselves. Patients with dyspnea or orthopnea are unable to lie supine. Dyspnea and orthopnea re er to dif culty breathing; this may be due to a heart condition, asthma, strenuous exercise, or excessive anxiety. Hypertension re ers to the condition o elevated blood pressure. 13. (C) T e degree o anterior and posterior motion is occasionally diminished with a whiplash-type injury. Anterior ( orward, exion) and posterior (backward, extension) motion is evaluated in the lateral position with the patient assuming exion and extension as best as he or she can. Le and right bending images o the thoracic and lumbar vertebrae are obtained requently when evaluating scoliosis. T e AP openmouth projection is used to evaluate the rst two cervical vertebrae. T e moving mandible AP projection is used to demonstrate the entire cervical spine while blurring out the superimposed mandible. 14. (B) Suf cient inspiration is demonstrated by the visualization o 10 posterior ribs projected above the diaphragm. Rotation o the chest is detected by asymmetry in the distance between the medial ends o the clavicles and the vertebral column. T e scapulae should be ree o superimposition with the lung elds; this is accomplished by rolling the shoulders orward while positioning or the PA projection. 15. (C) When high-speed electrons strike sur aces other than the tungsten target, x-rays may be produced and emitted in all directions. X-ray tubes, there ore, have a lead-lined metal protective housing to absorb much o this “leakage radiation.” Leakage radiation must not exceed 100 mR/h at a distance o 1 m rom the tube. Because the production o x-radiation requires the use o exceedingly high voltage, the tube housing also serves to protect rom electric shock. T e production o x-rays involves the production o large quantities o heat, which can be damaging to the x-ray tube. T ereore, an oil coolant surrounds the x-ray tube to urther insulate it and to absorb heat rom the x-ray tube structures.

16. (C) Interviewing skills and the collection o valuable, objective, and subjective patient data (clinical history) are an important unction o the healthcare pro essional. Objective data are those that are discernible to the senses o the interviewer—objective signs that can be heard, seen, or elt. Subjective data are those that can be discerned only by the patient— pain, emotions, and so on. Chie complaint is the principal medical problem as stated by the patient. 17. (C) As ltration is added to the x-ray beam, the lower-energy photons are removed, and the overall energy or wavelength o the beam is greater. As kilovoltage is increased, more high-energy photons are produced, and again, the overall or average energy o the beam is greater. An increase in milliamperage serves to increase the number o photons produced at the target but is unrelated to their energy. 18. (A) T e gures are axial C images o the abdomen with contrast. In Figure A, the liver (number 1 le lobe; number 6 right lobe; number 3 caudate lobe), barium- lled stomach (number 2), spleen (number 5), and aorta (number 4) are seen in image A. More in erior structures such as the in erior vena cava (number 5) and kidneys (number 9 and number 10) are seen in image B. 19. (B) Image B is an axial C section o the abdomen with contrast. Structures demonstrated include the barium- lled stomach (number 1), the gallbladder (number 2), duodenum (number 3), pancreas (number 4), IVC (number 5), le adrenal gland (number 6), aorta (number 7), spleen (number 8), le kidney (number 9), right kidney (number 10), and liver (number 11). 20. (A) Heparin is produced by the body (especially in the liver) and unctions to prevent intravascular clotting. Heparin is also produced arti cially and used to treat thromboembolic disorders. Lidocaine and Benadryl are drugs that are usually available on crash carts or emergency use. Lidocaine is used to treat ventricular arrhythmias, and Benadryl is used to treat allergic reactions and acute anaphylaxis. 21. (C) Emphysema is a chronic obstructive pulmonary disease (COPD) characterized by pathologic distension o the pulmonary alveoli with (destructive) changes in their walls, resulting in a loss o elasticity. Emphysema is seen occasionally ollowing asthma or

Answers: 13–28

tuberculosis, but it is caused most requently by cigarette smoking. Because the emphysematous patient’s greatest dif culty is exhalation, it becomes a conscious, orced e ort. Breathing is shallow and rapid. Forced and ine ective breathing results in expansion o the AP diameter o the chest and elevated shoulder girdle in established emphysema. Hyperventilation results rom too requent deep breaths in the anxious or tense individual. T is results in a eeling o dizziness and tingling o the extremities. 22. (B) A computed tomographic (C ) imaging system has three component parts—a gantry, a computer, and an operator console. T e gantry component includes an x-ray tube, a detector array, a high-voltage generator, a collimator assembly, and a patient couch with its motorized mechanism. T e computer is exceedingly sophisticated, per orming thousands o calculations simultaneously per second. It is responsible or image reconstruction and postprocessing unctions. At the operator console, somewhat similar to a control panel used in projection radiography, has the controls or equipment operation and image manipulation. echnical actors are selected and monitored here, adjustments can be made, and the patient couch is operated. 23. (D) T e radiographer selects a processing algorithm by selecting the anatomic part and particular projection on the computer/control panel. T e CR unit then matches that in ormation with a particular lookup table (LU )—a characteristic curve that best matches the anatomic part being imaged. T e observer is able to review the image and, i desired, change its appearance (through “windowing”); doing so changes the LU . Histogram analysis and use o the appropriate LU together unction to produce predictable image quality in CR. In addition, the radiographer can manipulate, that is, change and enhance, the digital image displayed on the display monitor through postprocessing. One way to alter image contrast and/or brightness is through windowing. T e term windowing re ers to some change made to window width and/or window level, that is, a change in the LU . Change in window width a ects change in the number o gray shades, that is, image contrast. Change in window level a ects change in the image brightness. T ere ore, windowing and other postprocessing mechanisms permit the radiographer to a ect changes in the image and produce

383

“special e ects,” such as contrast enhancement, edge enhancement, and image stitching. 24. (C) Fluoroscopic skin dose is greater than radiographic skin dose because the x-ray source is much closer to the patient. T e generally accepted rule is that the skin receives 2 rad/min/mA. T ere ore, 2 rad/min or 5 minutes equals 10 rad/mA. At 1.5 mA, the patient dose is 15 rad (2 rad/5 min/1.5 mA). 25. (C) Air– uid levels are demonstrated in the erect or decubitus position. Grid radiography requires about a 3 to 4 times greater dose than nongrid radiography. A right lateral decubitus projection without a grid, then, would demonstrate uid levels with a considerably smaller dose to the in ant. A recumbent AP projection would not demonstrate air– uid levels. 26. (C) T e radial head and neck are projected ree o superimposition in the AP oblique projection (lateral rotation) o the elbow. T e humeral capitulum is also well demonstrated in this external oblique position. T e AP oblique projection (medial rotation) o the elbow superimposes the radial head and neck on the proximal ulna. It demonstrates the olecranon process within the olecranon ossa, and it projects the coronoid process ree o superimposition. 27. (B) In mutual induction, two coils are in close proximity, and a current is supplied to one o the coils. As the magnetic eld associated with every electric current expands and “grows up” around the rst coil, it interacts with and “cuts” the turns o the second coil. T is interaction, motion between magnetic eld and coil (conductor), induces an electromotive orce (em ) in the second coil. T is is mutual induction, the production o a current in a neighboring circuit. rans ormers, such as the high-voltage trans ormer and the lament (stepdown) trans ormer, operate on the principle o mutual induction. T e autotrans ormer operates on the principle o sel -induction. Both the transormer and the autotrans ormer require the use o alternating current. 28. (B) Pathologic processes and abnormal conditions that alter tissue composition or thickness can have a signi cant e ect on receptor exposure. T e radiographer must be aware o these variants and processes to make an appropriate and accurate adjustment o technical actors.

384

7: Practice Test 2

Examples o additive pathologic conditions: • • • • • • •

Ascites Rheumatoid arthritis Paget disease Pneumonia Atelectasis Congestive heart ailure Edematous tissue

Examples o destructive pathologic conditions: • • • • • •

Osteoporosis Osteomalacia Pneumoperitoneum Emphysema Degenerative arthritis Atrophic and necrotic conditions

29. (B) T e overall chance that a person will become in ected with HIV is high with entry sites such as the anus, broken skin, shared needles, in ected blood products, and perinatal exposure. Low-risk entry methods include oral and nasal, conjunctiva, and accidental needle stick. 30. (B) T e term parenteral denotes any medication route other than the alimentary canal (by mouth). Examples o parenteral routes are subcutaneous, intravenous, intramuscular, and intracardiac. T e speed o absorption varies with the route used. 31. (B) T e RAO position is shown. T e RAO position is o en used to superimpose the sternum onto the heart shadow, providing uni orm receptor exposure throughout the sternum. T is position is also used to see axillary portions o le anterior ribs; in the anterior oblique positions, the a ected side is away rom the IR. T e RAO position can also be used to demonstrate the barium- lled pylorus and duodenum, and the esophagus can be projected between the vertebrae and heart in this position. T e degree o obliquity depends on the patient’s body habitus—greater obliquity is required or thinner chests. Barium- lled gastric undus would be demonstrated in either the AP recumbent or LPO position. 32. (A) It is occasionally necessary to view the lung apices ree o superimposition with the clavicles. T is objective can be achieved in an AP axial projection. T e patient is positioned AP erect with the CR directed 15 degrees cephalad, entering the

manubrium. An AP axial projection can also be obtained with the patient in the lordotic position. I suf cient lordosis can be assumed, the CR is directed perpendicular to the IR. 33. (B) I it is desired to determine entrance skin exposure (ESE), a small ionization chamber (pocket dosimeter) can be placed on the skin, and the approximate ESE can be read immediately. T ese devices are readily imaged, however, and are awkward to position. For these reasons, thermoluminescent dosimeters ( LDs) or optically stimulated luminescence (OSL) dosimeters are more easily used; they are precise and will not inter ere with the radiographic image. T e acceptable ESE or a PA chest is approximately 20 mR (12–26 mR is the acceptable range). An image taken with an ESE o 6 mR would be underexposed and require repeating. Similarly, ESEs o 38 mR and 0.6 R (600 mR) would lead to overexposed images that would need to be repeated. 34. (D) Patient demographic and examination in ormation originates rom the hospital/ acility HIS, where it is obtained when the patient is initially registered. T at in ormation is available or retrievable when the patient is scheduled, or arrives, or imaging services. ypical patient in ormation includes name, DOB or age, sex, ID number, accession number, examination being per ormed, date and time o examination. Additional in ormation may be available on the examination requisition; more in ormation is usually entered by the technologist at the time o the examination. A eature that is use ul in sorting examinations and decreasing (but not eliminating) errors is the Modality Work List (MWL). T e MWL “brings up” existing RIS in ormation, that is, the examinations scheduled or each imaging area— or example, x-ray, C , MR, mammography, ultrasound, etc. T e technologist selects the correct patient, which includes that patient’s particular demographics, rom the particular modality work list. It is essential that the technologist is attentive to detail and accuracy when entering patient in ormation; errors in patient demographics entry, and entry duplication, must be avoided. 35. (D) Structures located behind the parietal peritoneum are re erred to as retroperitoneal. Retroperitoneal structures include the kidneys, adrenal glands,

Answers: 29–43

pancreas, duodenum, ascending and descending colon, portions o the aorta, and the in erior vena cava. 36. (C) A beveled ocal track extends around the periphery o the anode disk; when a small angle is used, the beveled edge allows or a smaller e ective ocal spot and better detail. T e disadvantage, however, is that photons are noticeably absorbed by the “heel” o the anode, resulting in a smaller percentage o x-ray photons at the anode end o the x-ray beam and a concentration o x-ray photons at the cathode end o the beam. T is is known as the anode heel e ect and can cause a primary beam variation o up to 45%. T e anode heel e ect becomes more pronounced as the SID decreases, as IR size increases, and as target angle decreases. 37. (A) rans ormers and autotrans ormers require alternating current (AC) to operate. Number 1 is the autotrans ormer, which operates on the principle o sel -induction. It is rom here that actual kilovolt selection takes place. Numbers 2 and 3 are the primary and secondary coils o the step-up/ high-voltage trans ormer, which operates on the principle o mutual induction. Number 5 is the recti cation system, which serves to change AC to unidirectional current. T e recti cation system is needed because the x-ray tube (number 7) operates most ef ciently on unidirectional current. 38. (A) T e autotrans ormer is labeled 1, the primary coil o the high-voltage trans ormer is labeled 2, the grounded milliampere meter is labeled 4, and the lament circuit is labeled 6. T e recti cation system, which is used to change alternating current to unidirectional current, is indicated by number 5. T e recti cation system is located between the secondary coil o the high-voltage (step-up) transormer (number 3) and the x-ray tube (number 7). 39. (B) Anemia is a blood condition characterized by a decreased number o circulating red blood cells and decreased hemoglobin; it has many causes. Adequate hemoglobin is required to provide oxygen to the body. Anemia is treated according to its cause. Hematuria is the term used to describe blood in the urine and is unrelated to anemia. 40. (A) Resolution describes how closely ne details may be associated and still be recognized as separate

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details be ore seeming to blend into each other and appear “as one.” T e degree o resolution trans erred to the IR is a unction o the resolving power o each o the system components and can be expressed in line pairs per millimeter (lp/mm). It can be measured using a resolution test pattern; a variety o resolution test tools are available. T e star pattern generally is used or ocal-spot-size evaluation, whereas the parallel-line type is used or evaluating intensi ying screens. Resolution can also be expressed in terms o line-spread unction (LSP) or modulation trans er unction (M F). LSP is measured using a 10 µm x-ray beam; M F measures the amount o in ormation lost between the object and the IR. 41. (D) High- requency generators rst appeared in mobile x-ray units and were then adopted by mammography and C equipment. oday, more and more radiographic equipment uses highrequency generators. T eir compact size makes them popular, and the act that they produce nearly constant-potential voltage helps to improve image quality and decrease patient dose ( ewer low-energy photons to contribute to skin dose). 42. (A) I the SID is above or below the recommended ocusing distance, the primary beam at the lateral edges will not coincide with the angled lead strips. Consequently, there will be absorption o the primary beam, termed grid cuto . I the grid ailed to move during the exposure, there would be grid lines throughout. CR angulation in the direction o the lead strips is appropriate and will not cause grid cuto . I the CR were o -center, there would be uni orm loss o receptor exposure. 43. (C) A signed consent orm (in ormed consent) is not necessary prior to per orming an upper GI series. In ormed consent is necessary be ore perorming any procedure that is considered invasive or that carries considerable risk. A myelogram, a cardiac catheterization, and an interventional vascular procedure are all invasive procedures, and all carry some degree o risk. A physician should explain to the patient what those risks are as well as the risk o not having the procedure. In addition, the patient should be made aware o alternative procedures and the risks associated with the alternatives. Only a er the patient has been made aware and all questions have been answered appropriately

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7: Practice Test 2

should the in ormed consent be signed. A radiographer is not responsible or obtaining in ormed consent. However, in some institutions, it may be departmental procedure or the radiographer to check the chart and see whether there is a signed consent orm in place. 44. (C) T e tangential (“sunrise”) projection is used to demonstrate the articular sur aces o the emur and patella. It is also used to demonstrate vertical ractures o the patella. T e AP, PA, and oblique projections o the knee are used primarily to evaluate the joint space and articulating structures. T e tunnel view is used to demonstrate the intercondyloid ossa. 45. (D) Motion causes unsharpness that destroys detail. Care ul and accurate patient instruction is essential or minimizing voluntary motion. Suspended respiration eliminates respiratory motion. Using the shortest possible exposure time is essential to decrease involuntary motion. Immobilization can also be very use ul in eliminating motion unsharpness. 46. (B) Flat-panel detectors used in DR are o en made o an amorphous selenium (a-Se)–coated thin- lm transistor ( F ) array. T ey unction to convert the x-ray energy (emerging rom the radiographed part) into an electrical signal. T e F capacitors send the electrical signal to the analog-to-digital converter (ADC) to be changed to a digital signal. Amorphous selenium re ers to a crystalline material (selenium) that lacks its crystalline structure. Amorphous selenium or silicon is used to produce the direct-conversion at-panel detectors used in DR. 47. (A) A 1984 review o radiation exposure data revealed that the average annual dose equivalent or monitored radiation workers was approximately 0.23 rem (2.3 mSv). T e act that this is approximately one-tenth the recommended limit indicates that the limit is adequate or radiation protection purposes. T ere ore, the NCRP reiterates its 1971 recommended annual limit o 5 rem (50 mSv). 48. (D) A spinning-top test may be per ormed to evaluate timer accuracy or recti er ef ciency in singlephase equipment. T e number o dots or dashes imaged on the IR is counted and should equal the

number o radiation “pulses” occurring during that exposure time. Because three-phase equipment does not emit pulsed radiation but rather almost constant potential, a synchronous spinning top must be used to evaluate timer accuracy. T e resulting image is a solid arc. T e angle o the arc is measured and should correspond to the known correct angle. 49. (B) Retrograde urography is not considered a unctional study o the urinary system. IVU, and excretory/descending urography are all considered unctional urinary tract studies because the contrast medium is introduced intravenously and excreted by the kidneys. Retrograde urography involves introduction o contrast medium into the kidneys via catheter, thereby demonstrating their structure but not their unction. 50. (B) X-ray photons are produced in two ways as high-speed electrons interact with target tungsten atoms. First, i the high-speed electron is attracted by the nucleus o a tungsten atom and changes its course, as the electron is “braked,” energy is given up in the orm o an x-ray photon. T is is called Bremsstrahlung (“braking”) radiation, and it is responsible or most o the x-ray photons produced at the conventional tungsten target. Second, a highspeed electron having an energy o at least 70 keV may eject a tungsten K-shell electron, leaving a vacancy in the shell. An electron rom the next energy level, the L shell, drops down to ll the vacancy, emitting the di erence in energy as a K-characteristic ray. Characteristic radiation makes up only about 15% o the primary beam. 51. (B) T e (diarthrotic) sternoclavicular joints are ormed by the medial (sternal) extremities o the clavicles and the clavicular notches o the manubrium (o the sternum). T ey can be demonstrated in the LAO and RAO positions. T e LAO projection demonstrates the le sternoclavicular joint, whereas the RAO projection demonstrates the joint on the right. T e patient is obliqued about 15 degrees with the side o interest adjacent to the IR. 52. (A) When a change to a larger diameter mode is made, the voltage on the electrostatic ocusing lenses is decreased, and the result is a less magnif ed but brighter image. T e milliamperage will be automatically decreased to compensate or the increase in

Answers: 44–57

brightness, resulting in lower patient dose in the larger diameter modes. 53. (A) Hospital-acquired in ections (HAIs) are also re erred to as nosocomial. Despite the e orts o in ectious disease departments, HAIs continue to be a problem in hospitals today. T is is at least partly due to there being a greater number o older, more vulnerable patients and an increase in the number o invasive procedures per ormed today (i.e., needles and catheters). T e most requent site o HAI is the urinary tract, ollowed by wounds, the respiratory tract, and blood. 54. (A) T e control badge is an important part o the monitoring system. It should be stored somewhere away rom radiation sources. At the end o the monitoring period, when the badges are returned to the dosimetry service, the exposure to the control badge (which should be zero) is compared with the exposure received by the rest o the personal monitors. I the control badge is stored near radiation or used to replace someone’s lost badge, there is no standard or comparison or the rest o the group o monitors. 55. (B) In the 1990s, the implementation o slip ring technology allowed continuous rotation o the x-ray tube (through elimination o cables) and simultaneous couch movement. Sixth-generation C scanning is termed helical (or spiral) C —permitting acquisition o volume multislice scanning. oday’s helical multislice scanners, employing thousands o detectors (up to 60+ rows), can obtain uninterrupted data acquisition o 128 “slices” per tube rotation and can per orm 3D multiplanar re ormation (MPR). Fi h-generation C is electron beam; ultrahigh-speed C is used speci cally or cardiac imaging. 56. (D) T e human body is composed o approximately 80% water; the remaining 20% is a combination o substances such as proteins, carbohydrates, and lipids. T e smallest unctional unit o the body is the cell; the structure/content o which o en determines its unction. Cells orm tissues and organs that also have unctional characteristics. T e two basic types o cells are somatic and genetic. Somatic cells are all the body’s cells (bone, muscle, nerve, etc.) except those concerned with reproduction—those cells are termed genetic.

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DNA is located in the nucleus o each cell, packaged into thread-like structures called chromosomes. Each chromosome is made up o DNA tightly coiled many times around proteins called histones that support its structure. Passed rom parents to o spring, DNA contains the speci c instructions that make each individual unique. Chromosomes are visible, under microscope, in the cell’s nucleus only when the cell is dividing (mitosis). Most o what researchers know about chromosomes has been learned by observing chromosomes during mitotic activity. Division o somatic cells is mitosis, while (reduction) division o genetic cells is meiosis. Every chromosome has a constricted portion called its centromere, which divides the chromosome into two sections, or “arms.” T e chromosome’s short arm is re erred to as its “p arm.” T e chromosome’s long arm is re erred to as its “q arm.” T e location o the centromere on each chromosome is o en used to assist description o the location o speci c genes. 57. (B) According to the inverse-square law o radiation, as the distance between the radiation source and the IR decreases, the exposure rate increases. T ere ore, a decrease in technical actors is rst indicated to compensate or the distance change. T e ollowing ormula (exposure-maintenance ormula) is used to determine new milliampereseconds values when changing distance: mAs1 D12 = 2 mAs2 D2 Substituting known values: 8 5,184 = x 1, 600 5,184 x = 12, 800 T us, x = 2.47 mAs at 40-in SID. o then compensate or adding a 12:1 grid, you must multiply the 2.47 mAs by a actor o 5. T us, 12 mAs is required to produce a receptor exposure similar to the original image. T e ollowing are the actors used or milliampere-seconds conversion rom nongrid to grid: No grid = 1 × original mAs 5:1 = grid 2 × original mAs 6:1 = grid 3 × original mAs 8:1 = grid 4 × original mAs 12:1 = grid 5 × original mAs 16:1 = grid 6 × original mAs

388

7: Practice Test 2

58. (C) Invasion o privacy – that is, public discussion o privileged and con dential in ormation – is intentional misconduct. False imprisonment, such as unnecessarily restraining a patient, is also intentional misconduct. However, i a radiographer le a weak patient standing while leaving the room to check images or get supplies and the patient ell and sustained an injury, that would be considered unintentional misconduct or negligence.

developed muscles similarly will decrease or increase tissue density. 61. (D) Cells that are termed undi erentiated are immature or young. T ey have no speci c unction and/or structure. T ey are usually precursor cells; their most important unction is to divide. Mitosis is the most radiosensitive part o the cell cycle. 62. (A) T e oblique axial projection is valuable when the zygomatic arches cannot be demonstrated bilaterally with the submentovertical projection because they are not prominent enough or because o a depressed racture. T e patient still may be positioned as or an SMV projection, but the head is obliqued 15 degrees toward the side being examined. T is serves to move the zygomatic arch away rom superimposed structures and provides a slightly oblique axial projection o the arch.

59. (D) T e thicker and denser the anatomic part being studied, the less bright will be the uoroscopic image. Both milliamperage and kilovoltage a ect the uoroscopic image in a way similar to the way they a ect the radiographic image. For optimal contrast, especially taking into consideration the patient dose, higher kilovoltage and lower milliamperage generally are pre erred. 60. (D) T e radiographic subject (the patient) is composed o many di erent tissue types o varying densities, resulting in varying degrees o photon attenuation and absorption. T is di erential absorption contributes to the various shades o gray (scale o radiographic contrast) on the nished radiograph. Normal tissue density may be signi cantly altered in the presence o pathology. For example, destructive bone disease can cause a dramatic decrease in tissue density. Abnormal accumulation o uid (as in ascites) will cause a signi cant increase in tissue density. Muscle atrophy or highly

A

63. (C) Radiographic contrast is greatly a ected by changes in kilovoltage in SF/analog imaging (Figure 7-24). As kilovoltage increases, a greater number o high-energy photons are produced at the target. T ese photons are more penetrating, but they also produce more scattered radiation, contributing to lower radiographic contrast as a result o scattered radiation og. SF Radiograph B was made using 100 kVp and 18 mAs. SF Radiograph A was made o the same part using 80 kVp and 75 mAs, all other actors constant. T e image

B

Figure 7-24. A and B. From the American College o Radiology Learning File. Courtesy o the ACR.

Answers: 58–72

details in radiograph A are ar more perceptible as a result o less scattered radiation noise. 64. (B) Di erential absorption re ers to the di erent attenuation, or absorption, properties o adjacent body tissues. wo parts with widely di ering absorption characteristics will produce a high radiographic contrast. Frequently, technical actors that would properly expose one part will severely overexpose or underexpose the neighboring part (as with lungs vs. the thoracic spine). T is e ect can be minimized by the use o a compensating f lter or by the use o high kilovoltage ( or more uniorm penetration). Increased collimation is important in the control o patient dose and scattered radiation, not di erential absorption. 65. (B) T e image illustrates aliasing arti act, or Moiré e ect. Aliasing, or Moiré, has the appearance o somewhat wavy linear lines and can occur in computed radiography when using stationary grids. I the grid’s lead strip pattern (i.e., requency) matches the scanning (sampling) pattern o the scanner/reader, the resulting inter erence can cause aliasing (also called Moiré) arti act. When sampling requencies are decreased, aliasing/Moiré is less evident. As sampling requencies increase, aliasing/Moiré is more obvious. 66. (B) Since x-ray photons are produced at the tungsten target, they more readily diverge toward the cathode end o the x-ray tube. As they try to diverge toward the anode, they interact with and are absorbed by the anode “heel.” Consequently, there is a greater intensity o x-ray photons at the cathode end o the x-ray beam. T is phenomenon is known as the anode heel e ect. Because shorter SIDs and larger IR sizes require greater divergence o the x-ray beam to provide coverage, the anode heel e ect will be accentuated. 67. (D) Proper care o leaded protective apparel is required to ensure its continued use ulness. I lead aprons and gloves are olded, cracks will develop, and this will decrease their e ectiveness. Both items should be uoroscoped annually to check or the ormation o cracks. 68. (D) Since 50 ms is equal to 0.050 s, and since mA × time mAs, the original milliampere-seconds value was 15 mAs. Now, it is only necessary to determine

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what milliamperage must be used with 22 ms to provide the same 15 mAs (and thus the same receptor exposure). Because mA × time = mAs, 0.022x = 15 x = 682(700 mA) 69. (D) Follow-up studies have been done on individuals receiving accidental exposure to radiation (e.g., medical personnel, uranium miners, and children irradiated in vivo). Pioneer radiation workers developed leukemia and other cancers, their vision was clouded by the ormation o cataracts, and their lives were shorter than those o their colleagues. With today’s sophisticated equipment and knowledge o radiation protection, none o these situations should occur. 70. (C) Computed radiography (CR) is less expensive primarily because it is compatible with existing equipment. Digital radiography (DR) requires existing equipment to be modi ed or new equipment purchased. Because there is an image plate (IP), CR can be conveniently used or mobile studies; mobile units o en come equipped or DR as well. A er image processing, the IP is erased and reused. DR o ers the advantage o immediate visualization o the x-ray image; in CR, there is a short delay. 71. (A) Restriction o eld size is one important method o patient protection. However, the accuracy o the light eld must be evaluated periodically as part o a quality assurance (QA) program. Guidelines set orth or patient protection state that the collimator light and actual irradiated area must be accurate to within 2% o the SID employed. 72. (C) T e sternum has three parts: T e uppermost portion is the manubrium (and is quadrilateral in shape), the midportion is the body or gladiolus, and the distal portion is the ensi orm or xiphoid process. T e sternum supports the clavicles superiorly and provides attachment or the ribs laterally. T e rst seven pairs o ribs are true, or vertebrosternal, ribs because they attach directly to the sternum. T e ribs angle obliquely anteriorly and in eriorly so that their anterior portions are 3 to 5 in in erior to their posterior attachment. T e sternoclavicular joints a ord the only bony attachment between the thorax and the upper extremity.

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7: Practice Test 2

73. (C) T e synchronous timer is an older type o x-ray timer that does not permit very precise, short exposures. T e impulse timer permits a shorter, more precise exposure, and the electronic timer may be used or exposures as short as 0.001 s. T e electronic timer is very precise and accurate; it is widely used or rapid serial uoroscopic exposures. 74. (B) Exposure to high doses o radiation results in early e ects. Examples o early e ects are blood changes and erythema. I the exposed individual survives, then late, or long-term, e ects must be considered. Individuals who receive small amounts o low-level radiation (such as those who are occupationally exposed) are concerned with the late e ects o radiation exposure—e ects that can occur many years a er the initial exposure. Late e ects o radiation exposure, such as carcinogenesis, are considered to be related to the linear nonthreshold dose–response curve. T at is, there is no sa e dose; theoretically, even one x-ray photon can induce a later response. 75. (B) T e greater and lesser tubercles are prominences on the proximal humerus, separated by the bicipital groove. T e AP projection o the humerus in external rotation demonstrates the greater tubercle in pro le. With the arm placed in internal rotation, the humerus is placed in a true lateral position, and the lesser tubercle is demonstrated. 76. (B) As kilovoltage is increased, x-ray photons begin to interact with atoms o tissue via the Compton-scattered interaction. Scattered x-ray photons result, which serve only to add unwanted, undiagnostic densities (scattered radiation og) to the radiologic image. (While Compton scatter reduces patient dose compared with photoelectric interactions, it can pose a signi cant radiation hazard to personnel during uoroscopic procedures.) T ere ore, the use o optimal kilovoltage is recommended to reduce the production o scattered radiation. Scattered radiation is also a unction o the size and content o the irradiated eld. T e greater the volume and atomic number o the tissue, the greater is the production o scattered radiation. Although there is little that can be done about the atomic number o the structure to be radiographed, every e ort can be made to keep the eld size restricted to the essential area o interest in an e ort to decrease production o scattered

radiation. Grids have no e ect on the production o scattered radiation, but they are very e ective in removing scattered radiation rom the beam be ore it strikes the IR. 77. (C) T e AP oblique projection (LPO, RPO position/Grashey method) is used to demonstrate the glenoid ossa in pro le. T e position is most comortably per ormed in the erect position. T e body is rotated 35 to 45 degrees toward the a ected side. T e CR is directed 2 in medial and 2 in lateral to the upper outer border o the shoulder. T e glenohumeral joint space is open and the glenoid cavity is demonstrated in pro le. 78. (A) Because patient dose is regulated by the quantity o x-ray photons delivered to the patient, the milliampere-seconds value regulates patient dose. Highly energetic x-ray photons (high kilovoltage) are more likely to penetrate the patient rather than be absorbed by biologic tissue. Consequently, the use o high-kilovoltage and low–milliampereseconds technical actors is pre erred in an e ort to reduce patient dose. 79. (B) Whole-body dose is calculated to include all the especially radiosensitive organs. T e gonads, the lens o the eye, and the blood- orming organs are particularly radiosensitive. T e annual dose limit to the less sensitive skin, hands, and eet (extremities) is 50 rem/year. 80. (D) o accurately position a lateral orearm, the elbow must orm a 90-degree angle with the humeral epicondyles superimposed. T e radius and ulna are superimposed distally. Proximally, the coronoid process and radial head are partially superimposed. Failure o the elbow to orm a 90-degree angle or the hand to be lateral results in a less than satis actory lateral projection o the orearm. 81. (A) T e e ects o a quantity o radiation delivered to a body depend on several actors—the amount o radiation received, the size o the irradiated area, and how the radiation is delivered in time. I the radiation is delivered in portions over a period o time, it is said to be ractionated and has a less harm ul e ect than i the radiation were delivered all at once. With ractionation, cells have an opportunity to repair, and so some recovery occurs between doses.

Answers: 73–90

82. (A) T e line- ocus principle illustrates that as the target angle decreases, the e ective ocal spot decreases (providing improved recorded detail), but the actual area o electron interaction remains much larger (allowing or greater heat capacity). It must be remembered, however, that a steep (small) target angle increases the heel e ect, and part coverage may be compromised. 83. (A) As the exposed lm enters the processor rom the eed tray, it rst enters the developer section (number 1), where exposed silver bromide crystals are reduced to black metallic silver. T e lm then enters the f xer (number 2), where the unexposed silver grains are removed rom the lm by the clearing agent. T e lm then enters the wash section (number 3), where chemicals are removed rom the lm to preserve the image, improving archival quality. From the wash, the lm enters the dryer section (number 4). 84. (D) T e genetically signif cant dose (GSD) illustrates that large exposures to a ew people are cause or little concern when diluted by the total population. On the other hand, we all share the burden o the radiation that is received by the total population, and especially as the use o medical radiation increases, each individual’s share o the total exposure increases. 85. (C) A patient with a respiratory disease can transmit in ectious organisms via airborne contamination (i the patient sneezes or coughs). T ere ore, patients with upper respiratory tract in ection should be transported wearing a mask to prevent the possibility o airborne contamination. It is not necessary or the radiographer to be masked. 86. (B) Quality Control re ers to our equipment and its sa e and accurate operation. Various components must be tested at speci ed intervals and test results must be within speci ed parameters. Any deviation rom those parameters must be corrected. Examples o equipment components that are tested annually are the ocal-spot size, linearity, reproducibility, ltration, kV, and exposure time. Kilovoltage settings can most e ectively be tested using an electronic kV meter; to meet required standards, the kV should be accurate to within + /− 4 kV. Congruence is a term used to describe the relationship between the collimator light eld and

391

the actual x-ray eld—they must be congruent (i.e., match) to within 2% o the SID. Collimators should be inspected and veri ed as accurate semiannually, that is, twice a year. Reproducibility testing should speci y that radiation output be consistent to within + /− 5%. 87. (C) I the x-ray tube is angled signi cantly across the lead strips o a ocused grid, there is uni orm loss o receptor exposure (grid cuto ). Insuf cient or excessive distance with ocused grids causes loss o receptor exposure (grid cuto ) along the periphery o the image. Figure 7-10 demonstrates grid cuto everywhere except along a central vertical strip o the image. T is receptor exposure loss is due to the ocused grid’s being placed upside down. T us, the middle vertical lead strips allow x-rays to pass, but because the lead strips cant/angle laterally, they are directly opposite to the direction o the x-ray photons (rather than parallel to them), and severe grid cuto (loss o exposure to the IR) results. 88. (D) Single-phase current has a 100% voltage drop between peak voltages. T ree-phase current decreases this voltage drop considerably. T ree-phase, six-pulse current has about a 13% voltage drop between peak voltages, and three-phase, 12-pulse current has only about a 4% drop between peak voltages. However, high- requency current is almost constant potential, having less than 1% voltage ripple. 89. (C) T e reduction in x-ray beam intensity that results rom scattering (Compton) and absorption (photoelectric) processes is termed attenuation. T e anode heel e ect is related to the variation in x-ray beam intensity as it emerges in a divergent cone-shaped ashion rom the x-ray tube, with greater intensity being at the cathode end o the beam. Grid cuto is absorption o the use ul remnant beam as a result o misalignment or miscentering with the grid. 90. (B) When viewing the glenoid ossa rom the anterior, it is seen to angle posteriorly and approximately 45 degrees. o view it in pro le, then, it must be placed so that its sur ace is perpendicular to the IR. T e patient is positioned in a 45-degree oblique, a ected-side-down position, which places the glenoid ossa approximately perpendicular to the IR. T e arm is abducted slightly, the elbow is exed, and the hand and orearm are placed over

392

7: Practice Test 2

the abdomen. T e CR is directed perpendicular to the glenohumeral joint. 91. (A) O the given actors, kilovoltage and grid ratio will have a signi cant e ect on the scale o radiographic contrast. T e milliampere-seconds values are almost identical. Because decreased kilovoltage and high-ratio grid combination would allow the least amount o scattered radiation to reach the IR, thereby producing ewer gray tones, (A) is the best answer. Group (D) also uses low kilovoltage, but the grid ratio is lower, thereby allowing more scatter to reach the IR and producing more gray tones. 92. (D) Pulmonary vascular markings o en are prominent in the elderly and in smokers. Quiet, shallow breathing may be used during a long exposure (with a compensating low milliamperage) to blur them out. Oblique sternum, AP scapula, and lateral thoracic spine projections are examinations in which this technique is use ul. 93. (B) LE expresses the rate at which photon or particulate energy is trans erred to (absorbed by) biologic material (through ionization processes); it depends on the type o radiation and absorber characteristics. Relative biologic e ectiveness (RBE) describes the degree o response or amount o biologic change that one can expect o the irradiated material. As the amount o trans erred energy (LE ) increases ( rom interactions occurring between radiation and biologic material), the amount o biologic e ect/damage also will increase; that is, the two are directly related. 94. (B) As the kilovoltage is increased, a greater number o electrons are driven across to the anode with greater orce. T ere ore, as energy conversion takes place at the anode, more high-energy photons are produced. However, because they are higher-energy photons, there will be less patient absorption. 95. (D) T e input phosphor o image intensi ers is usually made o cesium iodide. For each x-ray photon absorbed by cesium iodide, approximately 5,000 light photons are emitted. As the light photons strike a photoemissive photocathode, a number o electrons are released rom the photocathode and ocused toward the output side o the image tube by voltage applied to the negatively charged electrostatic ocusing lenses. T e electrons are then accelerated

through the neck o the tube where they strike the small (0.5–1 in) output phosphor that is mounted on a at glass support. T e entire assembly is enclosed within a 2- to 4-mm thick vacuum glass envelope. Remember that the image on the output phosphor is minif ed, brighter, and inverted (electron ocusing causes image inversion). Input screen diameters o 5 to 12 in are available. Although smaller diameter input screens improve resolution, they do not permit a large FOV, that is, viewing o large patient areas. Dual- and triple- eld image intensi ers are available that permit magnif ed viewing o uoroscopic images. o achieve magni cation, the voltage to the ocusing lenses is increased and a smaller portion o the input phosphor is used, thereby resulting in a smaller FOV. Because mini cation gain is now decreased, the image is not as bright. T e mA is automatically increased to compensate or the loss in brightness when the image intensier is switched to magni cation mode. Entrance skin exposure (ESE) can increase dramatically as the FOV decreases (i.e., as magni cation increases). As FOV decreases, magnif cation o the output screen image increases, there is less noise because increased mA provides a greater number o x-ray photons, and contrast and resolution improve. T e ocal point in the magni cation mode is urther away rom the output phosphor (as a result o increased voltage applied to the ocusing lenses) and there ore the output image is magni ed. 96. (B) At a given exposure, higher-speed intensi ying screens (400) will emit more uorescent light, thereby increasing receptor exposure. Faster intensi ying screens, there ore, allow a considerable reduction in milliampere-seconds and, there ore, in patient dose and motion unsharpness. Intensi ying-screen speed is unrelated to scattered radiation. 97–98. (97, C; 98, A) T e gure shown is a double-contrast BE, oblique position. Since the le colic/splenic exure (number 1) is “open,” this is either an RPO or an LAO position. Also demonstrated are the descending colon (number 2), and transverse colon (number 3). Barium has re uxed into the ileum (number 5). T e ascending colon is seen as number 4. 99. (A) Remember that the x-ray beam is polyenergetic/heterogeneous—made up o many energies

Answers: 91–106

o x-ray photons. T e use o aluminum ltration to decrease the number o low-energy photons entering the body does not solve the problem completely. Remaining low-energy photons will be absorbed by the tissue structures closest to the entering x-ray beam. I the patient is positioned or an AP projection, anterior structures will receive a higher (entry) dose than posterior structures; that is, the exit dose is less. I the patient is positioned or a PA projection, posterior structures will receive the higher entry dose. Abdomen imaging perormed in the PA projection, whenever possible, will reduce exposure to the gonads. Skull and cervical spine projections per ormed PA will reduce exposure to the lens and to the thyroid. A PA chest radiograph delivers about 1 mrad to the thyroid; a PA skull radiograph, about 8 mrad; and a PA esophagram, about 9 mrad. An AP skull radiograph delivers about 92 mrad to the thyroid. As can be seen rom these gures, giving some thought to projection/position selection can decrease critical organ dose signi cantly. 100. (B) Subcutaneous emphysema is a pathologic distension o tissues with air; pulmonary emphysema is a chronic disease characterized by overdistension o the alveoli with air. Osteomalacia is a so tening o bone so that it becomes exible, brittle, and de ormed. All three o these conditions involve a decrease in tissue density and, there ore, require a decrease in technical actors. Atelectasis is a collapsed or airless lung; it requires an increase in technical actors. 101. (B) Bergonié and ribondeau theorized in 1906 that all precursor cells are particularly radiosensitive (e.g., stem cells ound in bone marrow). T ere are several types o stem cells in bone marrow, and the di erent types di er in degree o radiosensitivity. O these, red blood cell precursors, or erythroblasts, are the most radiosensitive. White blood cell precursors, or myelocytes, ollow. Platelet precursor cells, or megakaryocytes, are even less radiosensitive. Myocytes are mature muscle cells and are airly radioresistant. 102. (B) High-kilovoltage exposures produce large amounts o scattered radiation, and high-ratio grids are used o en with high-kilovoltage techniques in an e ort to absorb more o this scattered radiation. However, as more scattered radiation is

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absorbed, more primary radiation is absorbed as well. T is accounts or the increase in milliampere-seconds required when changing rom an 8:1 to a 16:1 grid. In addition, precise centering and positioning become more critical; a small degree o inaccuracy is more likely to cause grid cuto in a high-ratio grid. 103. (B) T e use o high kilovoltage with a airly low-ratio grid will be ine ective in ridding the remnant beam o scattered radiation. o improve contrast in this example, it has been decided to decrease the kilovoltage by 15%, thus making it necessary to increase the milliampere-seconds rom 5 to 10 mAs. Because an increase in the grid ratio to 12:1 is also desired, another change in milliampere-seconds will be required (remember, 10 mAs is now the old mAs): 10(old mAs) 4(8 :1 grid factor) = x(new mAs) 5(12 :1 grid factor) 4 x = 50 T us, x = 12.5 mAs at 90 kVp. Now, determine the exposure time required with 400 mA to produce 12.5 mAs: 400x = 12.5 x = 0.03-s exposure 104. (A) T ree-phase current is obtained rom three individual alternating currents superimposed on, but out o step with, one another by 120 degrees. T e result is an almost constant-potential current, with only a very small voltage ripple (4–13%), producing more x-rays per milliampere-second, and at a higher average energy, than single phase equipment. 105. (A) T e RAO position a ords a good view o the pyloric canal and duodenal bulb. It is also a good position or the barium- lled esophagus, projecting it between the vertebrae and the heart. T e le lateral projection o the stomach demonstrates the le retrogastric space, the recumbent PA projection is used as a general survey o the gastric suraces, and the recumbent AP projection with slight le oblique a ords a double contrast o the pylorus and duodenum. 106. (C) Excessive heat production is a major problem in x-ray production. O the energy required to produce x-rays, 0.2% is trans ormed to x-rays, and

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99.8% is trans ormed to heat. T e copper anode stem and the oil surrounding the x-ray tube help to move heat away rom the ace o the anode. Excessive heat can cause pitting o the anode (resulting in decreased output) or actual cracking o the anode or damage to the rotor bearings (resulting in tube ailure). As the cathode lament is heated or exposure a er exposure, some o its tungsten is vaporized and deposited on the inner sur ace o the glass envelope near the tube window. A er a time, this can cause electric arcing and tube ailure. T is is the most common cause o tube ailure because it can occur even with normal use.

must be tested at speci ed intervals and test results must be within speci ed parameters. Any deviation rom those parameters must be corrected. Examples o equipment components that are tested annually are the ocal-spot size, linearity, reproducibility, collimation, ltration, kV, and exposure time. Quality Assurance is associated with patients and sta and their interactions and relationships. Congruence is a term used to describe the relationship between the collimator light eld and the actual x-ray eld—they must be congruent (i.e., match) to within 2% o the SID. Postprocessing re ers to the windowing or other manipulation o a digital image.

107. (B) Proper unctioning o the phototimer depends on accurate positioning by the radiographer. T e correct photocell(s) must be selected, and the anatomic part o interest must completely cover the photocell(s) to achieve the desired receptor exposure. I a photocell is le uncovered, scattered radiation rom the part being examined will cause premature termination o exposure and an underexposed radiograph.

111. (C) An oblique projection o the cervical spine is shown. T e rst two cervical vertebrae are poorly visualized because o superimposition with the mandible; the chin should be elevated to correct this problem. Otherwise, the positioning is satisactory, with good demonstration o the remainder o the cervical intervertebral oramina. T e patient has been accurately rotated 45 degrees, and a 15- to 20-degree tube angle was used.

108. (A) T at portion o the x-ray beam striking the IR and representing image anatomy is re erred to as the signal. Some o the initial x-ray beam is absorbed via photoelectric interaction; some is scattered via Compton scatter (creating noise). Signal-to-noise ratio (SNR) is an important actor in all o medical imaging. Noise impairs image resolution; a high SNR is desirable (more signal, less noise). Generally speaking, SNR increases as mAs increases—however, this is at the expense o patient dose. It is the responsibility o the radiographer to select technical actors and techniques that will provide a quality diagnostic image while keeping the ALARA concept in mind and minimizing patient dose.

112. (B) An oblique projection o the cervical spine is shown. T e patient has been accurately positioned RAO with the MSP 45 degrees to the IR and the CR angled 15 to 20 degrees caudad, but the chin should be elevated to avoid superimposition on the rst two cervical vertebrae. T is position o ers excellent delineation o the intervertebral oramina (number 1) ormed by the adjacent vertebral notches o pedicles (number 2). T is projection gives an “on end” view o the transverse processes (number 3). A portion o the spinous processes (number 4) may be seen, especially in the lower cervical vertebrae.

109. (C) Because CR mammographic techniques operate at very low-kilovoltage levels, the IP ront material becomes especially important. T e use o so , low-energy x-ray photons is the underlying principle o mammography; any attenuation o the beam would be most undesirable. Special plastics that resist impact and heat so ening, such as polystyrene and polycarbonate, are used requently as IR ront material. 110. (C) Quality Control re ers to our equipment and its sa e and accurate operation. Various components

113. (B) o demonstrate the intercondyloid ossa, the CR must be directed perpendicular to the long axis o the tibia (Fig. 7-25). Because the knee is exed so that the tibia orms a 40-degree angle with the IR, the CR must be directed 40 degrees caudad to place the CR perpendicular to the long axis o the tibia. Directing the CR to the popliteal depression aligns the CR parallel with the knee joint space. 114. (C) T e sudden cessation o productive ventilation and circulation is called cardiopulmonary arrest. T e radiographer should be trained in basic li e support (BLS) or healthcare providers. T e

Answers: 107–121

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obtained with the patient prone and the x-ray beam directed horizontally. T e nished image can demonstrate small amounts o uid anteriorly and small amounts o air posteriorly.

Figure 7-25.

American Heart Association uses the acronym CAB, representing circulation, airway, breathing to help individuals remember CPR step sequence. Compressions should be about 100 per minute. A er about 30 compressions, airway should be established using the head-tilt, chin-li movement. I the victim is not breathing normally, the pro essional rescuer should begin mouth-to-mouth breathing. One cycle is considered to be 30 chest compressions ollowed by two rescue breaths. 115. (D) All the choices listed in the question should be part o a preliminary patient history be ore deciding to inject ionic or nonionic contrast media. As patients age, their general health decreases, and they are, there ore, more likely to su er rom adverse reactions. Patients with a history o respiratory disease, such as asthma or emphysema and COPD, are more likely to have a reaction and to su er greater distress in the event o a reaction. Patients with cardiac disease run an increased risk o changes in heart rate and myocardial in arction. Patients also should be screened or decreased renal or hepatic unction, sickle cell disease, diabetes, and pregnancy. 116. (A) T e dorsal decubitus position is obtained with the patient supine and the x-ray beam directed horizontally. T e nished image looks similar to a lateral projection o the chest. However, small amounts o uid will gravitate to the posterior chest, and small amounts o air will rise to the anterior chest. T e ventral decubitus position is

117. (A) Quality Control re ers to our equipment and its sa e and accurate operation. Various components must be tested at speci ed intervals and test results must be within speci ed parameters. Any deviation rom those parameters must be corrected. Examples o equipment components that are tested annually are the ocal-spot size, linearity, reproducibility, ltration, kV, and exposure time. Reproducibility speci es that radiation output must be consistent to within + /− 5%. Linearity tests x-ray output with increasing mAs; mR/mAs should be accurate to within 10%. Kilovoltage settings can most e ectively be tested using an electronic kV meter; to meet the required standards, the kV should be accurate to within + /− 4 kV. Congruence is a term used to describe the relationship between the collimator light eld and the actual x-ray eld—they must be congruent to within 2% o the SID. Radiographic equipment collimators should be inspected and veri ed as accurate semiannually. 118–119. (118, B; 119, B) An anterior view o the oot and ankle bones is shown. T e ankle joint is ormed by the articulation o the tibia, bula, and talus (number 7). T e tibial (medial) malleolus is labeled 8; the bular (lateral) malleolus is labeled 1. T e talus articulates with the calcaneus (number 2) in eriorly and with the navicular (number 6) anteriorly. T e cuboid (number 3) is seen anterior to the calcaneus, and the three cunei orms (number 5) are anterior to the navicular. 120. (D) Variance rom the normal bladder contour will be noted while the bladder is ull o contrast medium. However, a postmicturition (postvoiding) radiograph is also an essential part o an IVU/ IVP. T e presence o residual urine may be an indication o small tumor masses or, in male patients, enlargement o the prostate gland. 121. (B) Digital uoroscopy utilizes exposure, rather than continuous uoroscopic exposure. DF photospot images, which are simply still- rame images, need no chemical processing, require less patient dose (unless more than necessary are taken), and

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o er postprocessing capability. DF also o ers “road-mapping” capability—a technique use ul in procedures involving guidewire/catheter placement. Another eature is the “last image hold” eature. During the uoroscopic examination, the most recent uoroscopic image can be stored on the monitor (“last image hold”), thereby reducing the need or continuous x-ray exposure. T is technique can o er signi cant reductions in patient and personnel radiation exposure. T e length o the procedure is an important consideration in patient dose; the longer the .procedure the greater the dose. 122. (B) Sterile technique is required or administration o contrast media by the intravenous and intrathecal (intraspinal) methods. Aseptic technique is used or administration o contrast media by the oral and rectal routes as well as through the nasogastric tube. 123. (A) IVU requires the use o iodinated contrast media. Low kilovoltage (about 70 kVp) is usually used to enhance the photoelectric e ect and, in turn, to better visualize the renal collecting system. High kilovoltage will produce excessive scattered radiation and obviate the e ect o the contrast agent. A higher milliamperage with a short exposure time generally is pre erable. 124. (C) T e in raorbitomeatal line (IOML) is an imaginary line extending rom the in raorbital margin to the external auditory meatus and is represented by number 3. T e IOML is used or most lateral skull projections, including lateral projections o acial bones. T e skull is positioned so that the MSP is parallel to the IR, the interpupillary line is perpendicular to the IR, and the IOML is parallel to the long (transverse) axis o the IR. Number 1 is the glabellomeatal line, number 2 is the OML (orbitomeatal line), and number 4 is the acanthomeatal line. T ese baselines are used to obtain accurate positioning in skull radiography. 125. (D) Pneumothorax, the presence o air in the pleural cavity, is seen (as well as a large pleural e usion) in this image. A large pneumothorax is usually accompanied by a partial or complete collapse o the lung (atelectasis). Radiographic indications o atelectasis include elevation o the hemidiaphragm o the a ected side and an increase in tissue density o the collapsed lung.

T oracentesis is the procedure required to remove signi cant amounts o air, blood, or other uids in the pleural cavity. Rotation o the chest it is illustrated by unequal distances between the medial aspect o the clavicles and the vertebral column. Adequate inspiration is indicated by visualization o 10 posterior ribs seen above the diaphragm. 126. (D) Photoelectric interaction in tissue involves complete absorption o the incident photon, whereas Compton interactions involve only partial trans er o energy. T e larger the quantity o radiation and the greater the number o photoelectric interactions, the greater is the patient dose. Radiation dose to more radiosensitive tissues, such as gonadal tissue or blood- orming organs, is more harm ul than the same dose to muscle tissue. 127. (B) With the blood pressure cu wrapped snugly around the patient’s brachial artery and the pump in ated to approximately 180 mm Hg, the valve is opened only slightly to release pressure very slowly. With the stethoscope over the brachial artery, listen or the pulse while watching the mercury column (gauge). Note the point at which the rst pulse is heard as the systolic pressure. As the valve is opened urther, the sound is louder; the point at which it suddenly becomes so er is recorded as the diastolic pressure. 128. (B) T e AP oblique projection (LPO, RPO position/Grashey method) is used to demonstrate the glenoid ossa in pro le. T e position is most comortably per ormed in the erect position. T e body is rotated 35 to 45 degrees toward the a ected side. T e CR is directed 2 in medial and 2 in lateral to the upper outer border o the shoulder. T e glenohumeral joint space is open and the glenoid cavity is demonstrated in pro le. 129. (D) When the primary beam is restricted to an area near the periphery o the body, sometimes part o the illuminated area overhangs the edge o the body. I the exposure is then made, scattered radiation rom the tabletop (where there is no absorber) will undercut the part, causing excessive receptor exposure. I , however, a lead rubber mat is placed on the overhanging illuminated area, most o this scatter will be absorbed. T is is requently help ul in lateral lumbar spine and AP shoulder radiographs.

Answers: 122–135

130. (A) T e midcoronal plane (number 1) divides the body into anterior and posterior halves. A coronal plane is any plane parallel to the midcoronal plane. T e midsagittal plane (number 2) divides the body into le and right halves. A sagittal plane is any plane parallel to the midsagittal plane. A transverse or horizontal plane (number 3) is perpendicular to the midsagittal plane and midcoronal plane, dividing the body into superior and in erior portions. 131. (B) T e spinal cord is a column o nervous tissue about 17 in (44 cm) in length. It is somewhat attened anteroposteriorly and extends rom the medulla oblongata o the brain to the level o L2 within the spinal canal. Because the adult spinal cord ends at the level o L2, a lumbar puncture usually is per ormed below that level—generally, at the level o L3 to L4. A lumbar puncture may be per ormed or the removal o spinal uid or diagnostic purposes or or the injection o medications. 132. (D) Streptococcal pharyngitis (“strep throat”) is caused by bacteria. o know this, you have to remember that bacteria are classi ed according to their morphology (i.e., size and shape). T e three classi cations are spirals, rods (bacilli), and spheres (cocci). Viruses, unlike bacteria, cannot live outside a human cell. Viruses attach themselves to a host cell and invade the cell with their genetic in ormation. Various ungal in ections may grow on the skin (cutaneously), or they may enter the skin. Fungal in ections that enter the circulatory or lymphatic system can be deadly. Protozoa are one-celled organisms classi ed by their motility. Ameboids move by locomotion, agella use their protein tail, cilia possess numerous short protein tails, and sporozoans actually are not mobile. 133. (D) T e our types o body habitus are ( rom upper extreme to lower extreme) hypersthenic, sthenic, hyposthenic, and asthenic. T e gallbladder and stomach are higher and more lateral and the large bowel more peripheral in the hypersthenic individual. T e diaphragm is in a higher position in the hypersthenic individual. Recognition o a patient’s body habitus and its characteristics is an important part o accurate radiography. Bone porosity generally is unrelated to body habitus.

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134. (C) o change nongrid to grid exposure, or to adjust exposure when changing rom one grid ratio to another, remember the actor or each grid ratio: No grid = 5:1 grid = 6:1 grid = 8:1 grid = 12:1 grid = 16:1 grid =

1× 2× 3× 4× 5× 6×

original mAs original mAs original mAs original mAs original mAs original mAs

T ere ore, to change rom nongrid exposure to an 8:1 grid, multiply the original milliampere-seconds value by a actor o 4. T us, a new setting o 32 mAs is required. 135. (C) T e our types o body habitus, rom largest to most slight, are hypersthenic, sthenic, hyposthenic, and asthenic. In the gure, #1 is hyposthenic, #2 is asthenic, #3 is hypersthenic, and #4 is sthenic. T e characteristics and the prevalence o each habitus type are listed below. T e term body habitus re ers to the body’s physical appearance. Variations in body habitus have a signi cant e ect on the shape, location, and position o thoracic and abdominal organs, and can a ect their unction and motility. Illustrations 1 through 4 show how greatly the position o the diaphragm, lungs, and stomach can di er among the various body habitus. Body Habitus: Types, Characteristics, and Prevalence Hypersthenic and asthenic characterize the extremes in body types: Hypersthenic (5%) • Body large and heavy • Bony ramework thick, short, and wide • Lungs and heart high • Stomach transverse • Colon/large bowel peripheral • Gallbladder high and lateral Asthenic (10%) • Body slender and light • Bony ramework delicate • Thorax long and narrow • Stomach very low and long (“f sh hook”) • Colon/large bowel low, medial, and redundant • Gallbladder low and medial Sthenic and hyposthenic types characterize the more average body types: Sthenic (50%) • Build average and athletic • Similar to hypersthenic, but modif ed by elongation o abdomen and thorax Hyposthenic (35%) • Somewhat slighter, less robust • Similar to asthenic, but stomach, intestines, and gallbladder situated higher in abdomen

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136. (C) A phototimer is one type o automatic exposure device. When it is installed in an x-ray unit, it is calibrated to produce radiographic densities as required by the radiologist. Once the part being radiographed has been exposed to produce the proper receptor exposure, the phototimer automatically terminates the exposure. T e manual timer should be used as a backup timer should the phototimer ail to terminate the exposure, thus protecting the patient rom overexposure and the x-ray tube rom excessive heat load. Circuit breakers and uses are circuit devices used to protect circuit elements rom overload. In case o current surge, the circuit will be broken, thus preventing equipment damage. A rheostat is a type o variable resistor. 137. (D) T e hepatic (right colic) and splenic (le colic) exures are not generally well demonstrated in the AP and PA projections. o “open” the exures, oblique projections are required. T e le anterior oblique (LAO, le PA oblique) and right posterior oblique (RPO, right PA oblique) positions are used to demonstrate the splenic exure. T e hepatic exure is usually well demonstrated in the RAO and LPO positions. 138. (C) Contrast media may be administered in a variety o manners in cholangiography, including (1) an endoscope with a cannula placed in the hepatopancreatic ampulla (o Vater) or an ERCP, (2) a needle or small catheter placed directly in the common bile duct or an operative cholangiogram, (3) a very ne needle through the patient’s side and into the liver or a percutaneous transhepatic cholangiogram, and (4) via an indwelling -tube or a postoperative or -tube cholangiogram. 139. (B) Psychologist Abraham Maslow described a hierarchy, or pyramid, o needs with primary (physiologic) needs at the base and secondary (nonphysiologic) needs at higher levels. Maslow postulated that as the most basic survival needs are met, new needs emerge. At the bottom o the hierarchy are physiologic needs such as ood, water, air, rest, and so on. One step up in the hierarchy is sa ety and security. Next is love and belongingness, ollowed by sel -esteem and the esteem o others. Last is sel -actualization, which is a kind o spiritual growth, satisaction rom li e achievement, the eeling o leaving one’s mark.

140. (C) Radiographic rating charts enable the operator to determine the maximum sa e milliamperage, exposure time, and kilovoltage or a particular exposure using a particular x-ray tube. An exposure that can be made using the large ocal spot may not be sa e when the small ocal spot o the same x-ray tube is used. T e total number o heat units an exposure generates also in uences the amount o stress (in the orm o heat) imparted to the anode. Single-phase heat units are determined by the product o milliamperage × time × kilovoltage. T ree-phase and high- requency heat units are determined rom the product o milliamperage × time × kilovoltage × 1.4. In the examples given, then, group (A) produces 6,091 HU, group (B) produces 14,805 HU, group (C) produces 1,997 HU, and group (D) produces 7,106 HU. T ere ore, group (A) technical actors will deliver the least amount o heat to the anode. 141. (D) Converting rom an 8:1 grid to nongrid requires about a our old decrease in milliampere-seconds. Increasing the kilovoltage by 15% and cutting the milliampere-seconds in hal would reduce patient dose by hal . Increasing mAs will always increase exposure dose. T ere ore, the largest decrease will occur with removal o a grid. 142. (D) An in erosuperior projection (carpal canal/ tunnel position) is seen in the gure. T e pisi orm is seen as number 1, the triquetrum as number 2, the hook o the hamate is number 3, the capitate is number 4, the scaphoid is number 5, the trapezium is number 6, number 7 is the ulna and number 8 is the radius. 143. (C) Retrograde urography requires ureteral catheterization so that a contrast medium can be introduced directly into the pelvicalyceal system. T is procedure provides excellent opaci cation and structural in ormation but does not demonstrate the unction o these structures. Intravenous studies such as the IVU demonstrate unction. 144. (D) Generally, contrast medium is injected into the subarachnoid space between the third and ourth lumbar vertebrae. Because the spinal cord ends at the level o the rst or second lumbar vertebra, this is considered to be a relatively sa e injection site. T e cisterna magna can be used, but the risk o contrast medium entering the ventricles and causing side e ects increases. Diskography requires

Answers: 136–152

injection o contrast medium into the individual intervertebral disks. 145. (D) Body substance precaution procedures identi y various body uids as in ectious or potentially in ectious. T ese body substances include pleural, pericardial, peritoneal, and amniotic uids; synovial uid; cerebrospinal uid (CSF); breast milk; and vaginal secretions, as well as nasal secretions, tears, saliva, sputum, eces, urine, and wound drainage. 146. (B) Intervertebral joints are well visualized in the lateral projection o all the vertebral groups. Cervical articular acets ( orming apophyseal joints) are 90 degrees to the MSP and, there ore, are well demonstrated in the lateral projection. T e cervical intervertebral oramina lie 45 degrees to the MSP (and 15–20 degrees to a transverse plane) and, there ore, are demonstrated in the oblique position. 147. (D) Most needle sticks occur while attempting to recap a needle. Several diseases, including hepatitis and human immunode ciency virus (HIV) in ection, can be transmitted via a needle stick. T ereore, do not attempt to recap a needle, but rather dispose o the entire syringe with needle attached in the special container that is available. 148. (C) During radiography and uoroscopy, radiation scatters rom the patient in all directions. In act, the patient is the single most important scattering object in both radiographic and uoroscopic procedures. T e approximate intensity (quantity) o scattered radiation at 1 m rom the patient is 0.1% o the entrance dose. T ere ore, i the entrance dose or this image is 320 mR, the intensity o radiation at 1 m rom the patient is 0.1% o that, or 0.32 mR (0.001 × 320 = 0.32). 149. (B) Patient demographic and examination in ormation originates rom the hospital/ acility HIS, where it is obtained when the patient is initially registered. T at in ormation is available or retrievable when the patient is scheduled, or arrives, or imaging services. ypical patient in ormation includes name, DOB or age, sex, ID number, accession number, examination being per ormed, date and time o examination. Additional in ormation may be available on the examination requisition; more in ormation is

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usually entered by the technologist at the time o the examination. A eature that is use ul in sorting examinations and decreasing (but not eliminating) errors is the Modality Work List (MWL). T e MWL “brings up” existing RIS in ormation, that is, the examinations scheduled or each imaging area— or example, x-ray, C , MR, mammography, ultrasound, etc. T e technologist selects the correct patient, which includes that patient’s particular demographics, rom the particular modality work list. It is essential that the technologist is attentive to detail and accuracy when entering patient in ormation; errors in patient demographics entry, and entry duplication, must be avoided. PACS is used by healthcare acilities to economically store, archive, exchange, and transmit digital images rom multiple imaging modalities. RIS and HIS can be integrated with PACS or electronic health in ormation storage. T e purpose o HIS is to manage healthcare in ormation and documents electronically, and to ensure data security and availability. RIS is a system or tracking radiological and imaging procedures. RIS is used or patient registration and scheduling, radiology work ow management, reporting and printout, manipulation and distribution and tracking o patient data, and billing. RIS complements HIS and is critical to competent work ow to radiologic acilities. 150. (B) T e most hazardous time or abdominal irradiation is in the earliest stages o pregnancy, when many women are unaware that they are pregnant. For this reason, it is recommended that elective radiologic procedures be per ormed within the f rst 10 days ollowing the onset o the menses. It is during this time that the danger o irradiating a recently ertilized ovum is most unlikely. About 14 days be ore the onset o menses is when the ovarian ollicle ruptures and liberates an ovum. 151–152. (151, A; 152, B) A parietoacanthal projection (Waters position) o the skull is shown. T e chin is elevated suf ciently to project the petrous ridges below the maxillary sinuses (number 4). Note that the oramen rotundum is seen near the upper margin o the maxillary sinuses. Other paranasal sinus groups are not well visualized in this position, although a modi cation with the mouth open may be taken to demonstrate the

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sphenoidal sinuses. T is is also the single best projection to demonstrate the acial bones. T e zygomatic arch (number 2) is well demonstrated; the mandible, its angle (number 1), and the coronoid process (number 3) are also well demonstrated. T e odontoid process is seen projected through the oramen magnum. T e mastoid air cells are seen adjacent to the mandibular angle as multiple small, air- lled, bony spaces.

157. (B) A double- ocus tube has two ocal-spot sizes available. T ese ocal spots actually are two available paths on the ocal track. T ere are also two laments. When the small ocal spot is selected, the small lament is heated, and electrons are driven across to the smaller portion o the ocal track. When the large ocal spot is selected, the large lament is heated, and electrons are driven across to the larger portion o the ocal track.

153. (B) Esophageal varices are best demonstrated when there is increased venous pressure and when blood is owing against gravity. T ere ore, to demonstrate the twisted, dilated condition o venous varicosities, esophagrams must be perormed in the recumbent position. In the erect position, the veins appear more smooth and normal. T e Fowler position describes a position in which the patient’s head is higher than the eet, and the Sims position is pre erred or insertion o the enema tip.

158–159. (158, A; 159, B) An LPO projection o the lumbar spine is shown. T e patient is positioned so that the lumbar spine orms a 45-degree angle with the IR. T e apophyseal joints (those closest to the IR) are well demonstrated in this position. T e typical “Scotty dog” image is depicted. T e “ear” o the Scotty is the superior articular process (number 1), and the ront leg is the in erior articular process (number 4). T e Scotty’s eye is the pedicle, its body is the lamina (number 3), and its nose is the transverse process (number 2).

154. (A) With re erence to SF/analog imaging in the low kilovoltage ranges, a di erence o just a ew kilovolts makes a very noticeable radiographic di erence, that is, there is little latitude/margin or error. High kilovoltage techniques o er much greater latitude/margin or error. Grid ratio is unrelated to exposure latitude, but higher ratio grids o er less tube-centering/positioning latitude (i.e., leeway, or margin or error) than low ratio grids. Focal spot size is unrelated to latitude; its greatest impact is on resolution/recorded detail.

160. (C) With the patient in the lateral position, the MSP is parallel to the x-ray tabletop. Because the intervertebral oramina, which are ormed by the pedicles, are 90 degrees to the MSP, they are well demonstrated in the lateral projection. T e intervertebral joints (i.e., disk spaces) are also well demonstrated. T e spinal cord passes through the vertebral oramina, which would not be visualized in conventional radiography o the lumbar spine.

155. (D) T e S-shaped clavicle (“collar bone”) is usually the last bone to completely ossi y, at about age 21, and is one o the most commonly ractured bones in young people. Its medial end articulates with the sternum to orm the sternoclavicular joint; the clavicle articulates laterally with the scapula’s acromion process, orming the acromioclavicular joint. Superior dislocation o the acromioclavicular joint is a common athletic injury. 156. (A) T e sacroiliac joints angle posteriorly and medially 25 degrees to the MSP. T ere ore, to demonstrate them with an AP oblique projection, the a ected side must be elevated 25 degrees. T is places the joint space perpendicular to the IR and parallel to the CR. When the PA oblique projection is used, the una ected side will be elevated 25 degrees.

161. (A) Since 4,500 mrad is equal to 4.5 rad, i 4.5 rad were delivered in 6 minutes, then the dose rate must be 0.75 rad/min: 4.5 rad x rad = 6 min 1min 6x = 4.5 T us, x = 0.75 rad/min. 162. (D) Breast tissue has very low subject contrast, but it is imperative to visualize microcalci cations and subtle density di erences. Fine detail is necessary to visualize any microcalci cations; there ore, a small ocal-spot tube is essential. Short scale (high) contrast (and, there ore, low kilovoltage) is needed to accentuate any di erences in tissue density. A compression device serves to even out di erences in tissue thickness (thicker at the chest wall,

Answers: 153–172

thinner at the nipple) and decrease OID and helps to decrease the production o scattered radiation. 163. (C) Look over the choices again, keeping in mind the actors that a ect recorded detail. Looking rst at SID, the options may be reduced to (B) and (C) because the increase to a 40-in SID certainly will improve recorded detail. T ere is one other actor that will a ect detail—the speed o the system (intensi ying screens). Because a slower system will render better recorded detail, the best answer is (C). T e technical actors such as milliampere-seconds, kilovoltage, and grid ratio have no e ect on recorded detail. 164–165. (164, B; 165, D) An anterior view o the orearm is shown. T e proximal anterior sur ace o the ulna (number 8) presents a rather large pointed process at the anterior margin o the semilunar (trochlear) notch (number 5) called the coronoid process (number 6). T e olecranon process is identi ed as number 4, and the radial notch o the ulna is number 7. Distally, the ulnar head is number 9, and its styloid process is labeled 10. T e radius (number 12) is the lateral bone o the orearm. T e radial head is number 3, the radial neck is number 2, and the radial tuberosity is number 1. Distally, the radial styloid process is labeled 11. 166. (D) T e PA axial (Caldwell) projection o the paranasal sinuses is used to demonstrate the rontal and ethmoidal sinuses. T e CR is angled caudally 15 degrees to the OML. T is projects the petrous pyramids into the lower third o the orbits, thus permitting optimal visualization o the rontal and ethmoidal sinuses. 167. (D) Lead aprons are worn by occupationally exposed individuals during uoroscopic and mobile x-ray procedures. Lead aprons are available with various lead equivalents; 0.5- and 1.0-mm lead are the most common. T e 1.0-mm lead equivalent apron will provide close to 100% protection at most kilovoltage levels, but it is used rarely because it weighs anywhere rom 12 to 24 lb. A 0.25-mm lead equivalent apron will attenuate about 97% o a 50-kVp x-ray beam, 66% o a 75-kVp beam, and 51% o a 100-kVp beam. A 0.5mm lead-equivalent apron will attenuate about 99.9% o a 50-kVp beam, 88% o a 75-kVp beam, and 75% o a 100-kVp beam.

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168. (C) Idiopathic re ers to a disease o unknown or unclear cause. T e term systemic re ers to or concerns a (body) system. An epidemic describes a disease that swi ly a ects a large number o people in a particular geographic region. Anything that is or can be disease-producing is termed pathogenic. 169. (D) Because the toes curve naturally downward, the interphalangeal joints are not well demonstrated in the AP (dorsoplantar) projection. o “open” the interphalangeal joints, the CR should be directed 15 degrees cephalad. Another method is to place a 15-degree oam sponge wedge under the oot, elevating the toes 15 degrees rom the IR; the CR then would be directed perpendicularly. 170. (B) T e most commonly used method o low- ow oxygen delivery is the nasal cannula. It can be used to deliver oxygen at rates rom 1 to 4 mL/min at concentrations o 24% to 36%. T e nasal cannula also provides increased patient reedom to eat and talk, which a mask does not. Masks are used or higher- ow concentrations o oxygen, over 5 mL/ min; depending on the type o mask, they can deliver anywhere rom 35% to 60% oxygen. Respirators and ventilators are high- ow delivery mechanisms that are used or patients who are in severe respiratory distress or are unable to breathe on their own. Oxyhoods or tents generally are used or pediatric patients who may not tolerate a mask or cannula. T e amount o oxygen delivered is somewhat unpredictable, especially i the opening is accessed requently. Oxygen delivery may be between 20% and 100%. 171. (C) T e landmarks that can be used in radiography o the bony pelvis are the iliac crest, the ASIS, the pubic symphysis, the greater trochanter, the ischial tuberosity, and the tip o the coccyx. With the patient in the anatomic position, the emoral neck is located 21⁄2 in distal on a line drawn perpendicular to the midpoint o a line drawn between the ASIS and the pubic symphysis. It is recommended to rotate the legs inward about 15 degrees, whenever possible, to place the emoral neck parallel to the IR. 172. (D) When scheduling patient examinations, it is important to avoid the possibility o residual contrast medium covering areas o interest on later examinations. T e IVP should be scheduled rst because the contrast medium used is excreted

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rapidly. T e BE should be scheduled next. Finally, the upper GI series is scheduled. Any barium remaining rom the previous BE should not be enough to interere with the stomach or duodenum (a preliminary scout image should be taken in each case). 173. (D) Improper support o a patient’s ractured lower leg (tibia/ bula) while per orming radiography could result in movement o the racture ragments, which can cause tearing o the so tissue, nerves, and blood vessels. In addition, lack o support may cause muscle spasm, which can make closed reduction o some ractures dif cult. 174. (D) According to state and ederal law, personal radiation monitor reports must be retained as legal documents. In ormation that must be included in these documents includes the user’s personal data, that is, name, birth date, sex, identi cation number (usually, Social Security Number), type o monitor (e.g., lm badge, LD, or OSL dosimeter), radiation quality, dose equivalent (i.e., deep, eye, and shallow) or that exposure period (usually 1 month), the quarterly accumulated dose equivalent (i.e., deep, eye, and shallow), year-to-date dose equivalent (i.e., deep, eye, and shallow), li etime dose equivalent (i.e., deep, eye, and shallow), number o monitors received year to date, and inception date (month and year) o the dosimeter. 175. (A) T e emur is the longest and strongest bone in the body. T e emoral sha is bowed slightly anteriorly and presents a long, narrow ridge posteriorly called the linea aspera. T e proximal emur consists o a head that is received by the pelvic acetabulum. T e emoral neck, which joins the head and sha , normally angles upward about 120 degrees and orward (in anteversion) about 15 degrees. T e greater and lesser trochanters are large processes on the posterior proximal emur. T e intertrochanteric crest runs obliquely between the trochanters posteriorly; the intertrochanteric line parallels the intertrochanteric crest on the anterior emoral sur ace. T e intercondyloid ossa, a deep notch ound on the distal posterior emur between the large emoral condyles and the popliteal sur ace, is a smooth sur ace just superior to the intercondyloid ossa. 176. (C) Fidelity, veracity, nonmale cence, and bene cence are all ethical principles. Nonmalef cence is the

principle that re ers to the prevention o harm. Bene icence is the ethical principle that re ers to bringing about good or bene ting others. Fidelity re ers to aith ulness, and veracity re ers to truth ulness. 177. (C) A radiographer who ails to wear a lead apron when per orming portable radiography is in direct violation o the ARR Code o Ethics or the Pro ession o Radiologic echnology. Although this may seem to some to be a personal decision, the act is that our pro ession demands that we protect not only others but ourselves as well rom unnecessary radiation exposure. Participating in continuing education is every radiographer’s duty and not only is in keeping with the ARR Code o Ethics but now is also mandatory or renewal o ARR certi cation. Under normal circumstances, patient con dentiality is o the utmost importance, and radiographers always must respect a patient’s right to privacy. T ere are special circumstances, however, where a radiographer is negligent i he or she does not communicate con dential in ormation to the proper individuals. T ese cases include suspected cases o child abuse and any instance where the wel are o an individual or community is at risk. T e pro essional radiographer is encouraged to investigate new and innovative techniques. As technology continues to grow, we must grow with it. T ere are o en new and better ways to per orm procedures, especially as equipment changes occur. 178. (C) Hospital in ormation systems must ensure con dentiality in compliance with Health Insurance Portability and Accountability Act o 1996 (HIPAA) regulations. Most institutions now have computerized, paperless systems that accomplish the same in ormation transmittal; these systems must ensure con dentiality in compliance with HIPAA regulations. T e healthcare pro essional generally has access to the computerized system only via personal password, thus helping to ensure con dentiality o patient in ormation. All medical records and other individually identi able health in ormation, whether electronic, on paper, or oral, are covered by HIPAA legislation and by subsequent Department o Health and Human Services (HHS) rules that took e ect in April o 2001. 179. (B) Dysplasia re ers to abnormal development o tissue—o en demonstrated radiographically in skeletal imaging. Dif culty in speaking is termed

Answers: 173–187

dysphasia. Malposition re ers to an anatomic structure located in a place other than the norm, or example, situs inversus. Dif cult or pain ul breathing is termed dyspnea. 180. (D) Fidelity, veracity, nonmale cence, and bene cence are all ethical principles. Nonmalef cence is the principle that re ers to the prevention o harm. Benef cence is the ethical principle that re ers to bringing about good or bene ting others. Fidelity re ers to aith ulness, and veracity re ers to truth ulness. 181. (D) echnique charts are technical actor guides that help technologists produce radiographs with consistent receptor exposure and contrast. T ey suggest a group o technical actors to be used at a particular SID with a particular grid ratio, ocal-spot size, and CR angulation. echnique charts do not take into account the nature o the part (disease and atrophy). 182. (B) T e pregnant radiographer poses a special radiation protection consideration because the sa ety o the unborn individual must be considered. It must be remembered that the developing etus is particularly sensitive to radiation exposure. Established guidelines state that the occupational radiation exposure to the etus must not exceed 0.5 rem (500 mrem, or 5 mSv) during the entire gestation period. 183. (D) Epidemiologic studies indicate that AIDS can be transmitted only by intimate contact with body uids o an in ected individual. T is can occur through the sharing o contaminated needles, through sexual contact, and rom mother to baby at childbirth (perinatal). AIDS can also be transmitted by trans usion o contaminated blood. 184. (B) Venous blood is returned to the right atrium o the heart via the superior ( rom the upper part o the body) and in erior ( rom the lower body) venae cavae and the coronary sinus ( rom the heart substance). During atrial systole, the blood passes through the tricuspid valve into the right ventricle. During ventricular systole, the blood is pumped through the pulmonary semilunar valve into the pulmonary artery (the only artery to carry unoxygenated blood) to the lungs or oxygenation. Blood is returned via the pulmonary veins (the only veins

403

to carry oxygenated blood) to the le atrium. During atrial systole, blood passes through the mitral (bicuspid) valve into the le ventricle. During ventricular systole, the oxygenated blood is pumped through the aortic semilunar valve into the aorta. T e coronary arteries supply oxygenated blood to the myocardium. T e chordae tendineae are connective tissue bers that help to limit the movement o valve aps, preventing back ow o blood. 185. (A) Mature white blood cells (lymphocytes) are considered the most radiosensitive cells. Ova ( emale germ cells) are very radiosensitive, but not to the same degree as lymphocytes. Myocytes (muscle cells) and especially neurons (nerve cells) are actually radioresistant. 186. (D) Most o the occupational exposure received by radiographers is received during uoroscopy and mobile radiography, and the use o lead aprons is required during both these procedures. T e position o the personal monitor relative to the lead apron, there ore, becomes important. It is recommended that the badge be worn outside the lead apron at collar level. In this position, the badge will record the maximum possible exposure received by the radiographer and will provide a realistic estimate o thyroid and lens exposure. 187. (B) T e input phosphor o image intensi ers is usually made o cesium iodide. For each x-ray photon absorbed by cesium iodide, approximately 5,000 light photons are emitted. As the light photons strike a photoemissive photocathode, a number o electrons are released rom the photocathode and ocused toward the output side o the image tube by voltage applied to the negatively charged electrostatic ocusing lenses. T e electrons are then accelerated through the neck o the tube where they strike the small (0.5–1 in) output phosphor that is mounted on a at glass support. T e entire assembly is enclosed within a 2- to 4-mm thick vacuum glass envelope. Remember that the image on the output phosphor is minif ed, brighter, and inverted (electron ocusing causes image inversion). Input screen diameters o 5–12 in are available. Although smaller diameter input screens improve resolution, they do not permit a large FOV, that is, viewing o large patient areas. Dual- and triple- eld image intensi ers are available that permit magnif ed viewing o uoroscopic

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images. o achieve magni cation, the voltage to the ocusing lenses is increased and a smaller portion o the input phosphor is used, thereby resulting in a smaller FOV. Because mini cation gain is now decreased, the image is not as bright. T e mA is automatically increased to compensate or the loss in brightness when the image intensi er is switched to magni cation mode. Entrance skin exposure (ESE) can increase dramatically as the FOV decreases (i.e., as magni cation increases). As FOV decreases, magnif cation o the output screen image increases, there is less noise because increased mA provides a greater number o x-ray photons, and contrast and resolution improve. T e ocal point in the magni cation mode is urther away rom the output phosphor (as a result o increased voltage applied to the ocusing lenses) and there ore the output image is magni ed. 188. (D) Shape distortion is caused by misalignment o the x-ray tube, the body part to be radiographed, and the IR. An object can be alsely imaged ( oreshortened or elongated) as a result o incorrect placement o the tube, the part, or the IR. Only one o the three need be misaligned or distortion to occur. 189. (A) T e velocity and charge o particulate radiation determine the amount o energy trans erred (and, there ore, the number o ionizations) to the tissue traversed. A greater LE (number o ionizations) is delivered by particles with a slower velocity and greater charge. T e greater the LE and the number o ionizations, the greater is the biologic e ect. T e unit o absorbed dose is the rad (radiation absorbed dose). Rem is the acronym or radiation equivalent man—the unit o dose equivalent. 190. (D) Postoperative, or -tube, cholangiography requently is per ormed to evaluate the patency o the biliary ducts and to identi y any previously undetected stones. Following surgery, a -tube is le in place within the common bile duct, with the vertical portion o the extending outside the body. Water-soluble iodinated contrast medium is injected, and uoroscopic examination is carried out. 191. (C) Angina pectoris is a spasmodic chest pain that is requently due to oxygen de ciency in the myocardium. T e pain o en radiates down the le arm and up to the le jaw. Angina pectoris

attacks requently are associated with exertion or emotional stress in individuals with coronary artery disease. Pain may be relieved with a vasodilator such as nitroglycerin given sublingually or transdermally. Digitalis is used to treat congestive heart ailure. Dilantin is used in the control o seizure disorders, and cimetidine ( agamet) is used to treat duodenal ulcers. 192. (A) As the kilovoltage is increased, part penetration increases, and a greater range o densities (grays) will be apparent in SF imaging. T is is termed long scale or low contrast. In addition, as the kilovoltage and scale o grays increase, the exposure latitude increases in lm/screen imaging; the margin or error in technical actors becomes greater. As the mAs value is decreased in lm/ screen imaging to compensate or the increased kV, receptor exposure should remain the same. 193. (C) T e occupational dose limit is valid or beta, x-, and gamma radiations. Because alpha radiation is so rapidly ionizing, traditional personal monitors will not record alpha radiation. Because alpha particles are capable o penetrating only a ew centimeters o air, they are practically harmless as an external source. 194. (C) Dose Area Product (DAP) expresses the radiation dose leaving the x-ray tube times the area o the x-ray eld. DAP meters measure the product o in-air radiation and the area o the x-ray eld. T ere is heightened awareness o radiation skin dose today, particularly in interventional uoroscopic procedures. It is recommended that maximum radiation skin dose is better estimated using a DAP meter. T is is generally thought to provide more use ul in ormation in potential high-dose procedures then simply recording the uoroscopic time. T e DAP meter is a type o ionization chamber that is placed just beyond the x-ray collimators and must capture the entire x-ray eld to provide an accurate reading. 195. (A) When a patient’s elbow needs to be examined in partial exion, the lateral projection o ers little dif culty, but the AP projection requires special attention. I the AP projection is made with a perpendicular CR and the olecranon process resting on the table-top, the articulating sur aces are obscured. With the elbow in partial exion, two

Answers: 188–200

exposures are necessary to achieve an AP projection o the elbow joint articular sur aces. One is made with the orearm parallel to the IR (humerus elevated), which demonstrates the proximal orearm. T e other is made with the humerus parallel to the IR ( orearm elevated), which demonstrates the distal humerus. In both cases, the CR is perpendicular i the degree o exion is not too great or angled slightly into the joint space with greater degrees o exion. 196. (A) As SID increases, so does recorded detail because magni cation is decreased. T ere ore, SID is directly related to recorded detail. As ocal-spot size increases, recorded detail decreases because more penumbra is produced. Focal-spot size is thus inversely related to radiographic sharpness or recorded detail. ube current a ects receptor exposure and is unrelated to recorded detail. 197. (B) Standard blood and body uid precautions serve to protect healthcare workers and patients rom the spread o diseases such as AIDS and AIDS-related complex. Although the precautions are indicated or all patients, special care must be emphasized when working with patients whose in ectious status is unknown (e.g., the emergency trauma patient). Gloves must be worn i the radiographer may come in contact with blood or body uids. A gown should be worn i the clothing may become contaminated. Blood spills should be cleaned with a solution o 1 part bleach to 10 parts water. 198. (C) X-ray tube li e may be extended by using technical actors that produce a minimum o heat (a lower

405

milliampere-seconds and higher kilovoltage combination) whenever possible. When the rotor is activated, the lament current is increased to produce the required electron source (thermionic emission). Prolonged rotor time, then, can lead to shortened lament li e owing to early vaporization. Large exposures to a cold anode will heat the anode sur ace, and the temperature di erence between sur ace and interior can cause cracking o the anode. T is can be avoided by proper warming o the anode prior to use, thereby allowing suf cient dispersion o heat through the anode. 199. (D) T e thoriated tungsten lament o the cathode assembly is heated by its own lament circuit. T is circuit provides current and voltage to heat the lament to incandescence, at which time it undergoes thermionic emission (the liberation o valence electrons rom lament atoms). T e greater the number o electrons owing between the cathode and the anode, the greater is the tube current (mA). Rectif cation (single- or three-phase) is the process o changing alternating current to unidirectional current. A greater number o secondary trans ormer turns unctions to increase voltage and decrease current. 200. (C) T ere is no preparation required or an abdominal survey. For an upper GI series and a lower GI series (BE), the patient should be NPO, or have nothing by mouth, or 8 to 10 hours prior to the examination. In addition, a low-residue diet may be imposed, uid intake may be increased, and cleansing enemas and laxatives may be prescribed to rid the colon o ecal matter.

Subspecialty List

QUESTION NUMBER AND SUBSPECIALTY correspond to subcategories in each o the f ve ARRT examination specif cation sections 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30.

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Patient care and education Equipment operation and quality control Patient care and education Image acquisition and evaluation Radiation protection Patient care and education Imaging procedures Radiation protection Image acquisition and evaluation Radiation protection Imaging procedures Patient care and education Imaging procedures Image acquisition and evaluation Equipment operation and quality control Patient care and education Equipment operation and quality control Imaging procedures Imaging procedures Patient care and education Patient care and education Equipment operation and quality control Equipment operation and quality control Radiation protection Imaging procedures Imaging procedures Equipment operation and quality control Image acquisition and evaluation Patient care and education Patient care and education

31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65.

Imaging procedures Imaging procedures Radiation protection Patient care and education Imaging procedures Equipment operation and quality control Equipment operation and quality control Equipment operation and quality control Patient care and education Image acquisition and evaluation Equipment operation and quality control Image acquisition and evaluation Imaging procedures Imaging procedures Image acquisition and evaluation Equipment operation and quality control Radiation protection Equipment operation and quality control Imaging procedures Equipment operation and quality control Imaging procedures Equipment operation and quality control Patient care and education Radiation protection Equipment operation and quality control Radiation protection Image acquisition and evaluation Patient care and education Equipment operation and quality control Image acquisition and evaluation Radiation protection Imaging procedures Imaging procedures Image acquisition and evaluation Image acquisition and evaluation

Subspecialty List

66. 67. 68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 78. 79. 80. 81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92. 93. 94. 95. 96. 97. 98. 99. 100. 101. 102. 103. 104. 105. 106. 107. 108. 109. 110. 111. 112. 113. 114. 115. 116.

Image acquisition and evaluation Radiation protection Image acquisition and evaluation Radiation protection Equipment operation and quality control Radiation protection Imaging procedures Equipment operation and quality control Radiation protection Imaging procedures Image acquisition and evaluation Imaging procedures Radiation protection Radiation protection Imaging procedures Radiation protection Equipment operation and quality control Image acquisition and evaluation Radiation protection Patient care and education Equipment operation and quality control Image acquisition and evaluation Equipment operation and quality control Equipment operation and quality control Imaging procedures Image acquisition and evaluation Imaging procedures Radiation protection Equipment operation and quality control Equipment operation and quality control Image acquisition and evaluation Imaging procedures Imaging procedures Radiation protection Image acquisition and evaluation Radiation protection Equipment operation and quality control Image acquisition and evaluation Equipment operation and quality control Imaging procedures Equipment operation and quality control Image acquisition and evaluation Equipment operation and quality control Imaging procedures Equipment operation and quality control Image acquisition and evaluation Imaging procedures Imaging procedures Patient care and education Patient care and education Imaging procedures

117. 118. 119. 120. 121. 122. 123. 124. 125. 126. 127. 128. 129. 130. 131. 132. 133. 134. 135. 136. 137. 138. 139. 140. 141. 142. 143. 144. 145. 146. 147. 148. 149. 150. 151. 152. 153. 154. 155. 156. 157. 158. 159. 160. 161. 162. 163. 164. 165. 166. 167.

Equipment operation and quality control Imaging procedures Imaging procedures Imaging procedures Equipment operation and quality control Patient care and education Image acquisition and evaluation Imaging procedures Image acquisition and evaluation Radiation protection Patient care and education Imaging procedures Image acquisition and evaluation Imaging procedures Patient care and education Patient care and education Imaging procedures Image acquisition and evaluation Imaging procedures Equipment operation and quality control Imaging procedures Imaging procedures Patient care and education Equipment operation and quality control Radiation protection Imaging procedures Imaging procedures Imaging procedures Patient care and education Imaging procedures Patient care and education Radiation protection Equipment operation and quality control Radiation protection Imaging procedures Imaging procedures Imaging procedures Image acquisition and evaluation Imaging procedures Imaging procedures Equipment operation and quality control Imaging procedures Imaging procedures Imaging procedures Radiation protection Equipment operation and quality control Image acquisition and evaluation Imaging procedures Imaging procedures Imaging procedures Radiation protection

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168. 169. 170. 171. 172. 173. 174. 175. 176. 177. 178. 179. 180. 181. 182. 183. 184.

7: Practice Test 2

Patient care and education Imaging procedures Patient care and education Imaging procedures Patient care and education Patient care and education Radiation protection Imaging procedures Patient care and education Patient care and education Patient care and education Patient care and education Patient care and education Image acquisition and evaluation Radiation protection Patient care and education Patient care and education

Master Bibliography Adler AM, Carlton RR. Introduction to Radiologic Sciences and Patient Care. 5th ed. St. Louis, MO: Saunders Elsevier; 2012. ARR . New est Item Format or Radiography Examination. https://www.arrt.org/pd s/Exainations/item-Formats .pd . Accessed March 20, 2015. ASR Code o Ethics. https://www.asrt.org/docs/ practice-standards/codeofethics.pd BEIR Report VII. http://dels.nas.edu/dels/rpt_brie s/ beir_vii_ nal.pd Bontrager KL, Lampignano JP. extbook o Radiographic Positioning and Related Anatomy. 8th ed. St Louis, MO: Mosby; 2014. Bontrager KL, Lampignano JP. extbook o Radiographic Positioning and Related Anatomy. 7th ed. St Louis, MO: Mosby; 2010. Bushong SC. Radiologic Science or echnologists. 10th ed. St. Louis, MO: Mosby; 2013. Bushong SC. Radiologic Science or echnologists. 9th ed. St. Louis, MO: Mosby; 2008. Carlton RR, Adler AM. Principles o Radiographic Imaging. 5th ed. Albany, NY: Delmar; 2013. Carter C, Vealé B. Digital Radiography and PACS. 1st ed revised. St. Louis, MO: Mosby Elsevier; 2010. Chen MYM, Pope L, Ott DJ, eds. Basic Radiology. 1st ed. New York, NY: McGraw-Hill; 2004. Dutton AG, Linn-Watson A, orres LS. orres’ Patient Care in Imaging echnology. 8th ed. Philadelphia, PA: Lippincott; 2013.

185. 186. 187. 188. 189. 190. 191. 192. 193. 194. 195. 196. 197. 198. 199. 200.

Radiation protection Radiation protection Equipment operation and quality control Image acquisition and evaluation Radiation protection Imaging procedures Patient care and education Image acquisition and evaluation Radiation protection Radiation protection Imaging procedures Image acquisition and evaluation Patient care and education Equipment operation and quality control Equipment operation and quality control Imaging procedures

Ehrlich RA, Coakes DM. Patient Care in Radiography. 8th ed. St. Louis, MO: Mosby; 2013. Fosbinder RA, Kelsey CA. Essentials o Radiologic Science. 1st ed. New York, NY: McGraw-Hill; 2002. Fosbinder R, Orth D. Essentials o Radiologic Science. Baltimore, MD: Lippincott Williams & Wilkins; 2012. Frank ED, Long BW, Smith BJ. Merrill’s Atlas o Radiographic Positioning and Procedures. Vols 1, 2, and 3. 12th ed. St. Louis, MO: Mosby; 2012. Fuji Photo Film Co., Ltd. (FCR) Fuji Computed Radiography. Minato-Ku, Japan; 2002. McConnell H. T e Nature o Disease, Pathology or the Health Pro essions. 2nd ed. Wolters Kluwer Lippincott Williams & Wilkins; 2014. Mills WR. T e relation o bodily habitus to visceral orm, tonus, and motility. Am J Roentgenol. 1917;4:155–169. NCRP Report No. 116. Recommendations on Limits or Exposure to Ionizing Radiation. NCRP; 1987. NCRP Report No. 99. Quality Assurance or Diagnostic Imaging. NCRP; 1990. NCRP Report No. 160. Ionizing Radiation Exposure o the Population o the United States. NCRP; 2009. NCRP Report No. 102. Medical x-ray, Electron Beam and Gamma-Ray Protection or Energies up to 50 MeV (Equipment Design, Per ormance and Use). NCRP; 1989. Peart O. Mammography and Breast Imaging PREP. New York, NY: McGraw-Hill; 2012. Peart O. Lange Radiographic Positioning Flashcards. New York, NY: McGraw-Hill; 2014. Saia DA. Radiography PREP. 8th ed. New York, NY: McGraw-Hill; 2015.

Master Bibliography

Saia DA. Radiography PREP. 7th ed. New York, NY: McGraw-Hill; 2012. Saladin KS. Anatomy and Physiology: T e Unity o Form and Function. 7th ed. New York, NY: McGraw-Hill; 2015. Seeram E. Digital Radiography: An Introduction. Delmar: CENGAGE Learning; 2011. Selman J. T e Fundamentals o Imaging Physics and Radiobiology. 9th ed. Spring eld, IL: Charles C T omas; 2000. Shephard C . Radiographic Image Production and Manipulation. 1st ed. New York, NY: McGraw-Hill; 2003. Statkiewicz-Sherer MA, Visconti PJ, Ritenour ER, Haynes KW. Radiation Protection in Medical Radiography. 7th ed. St. Louis, MO: Mosby; 2014.

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Index Note: Page numbers ollowed by f re er to gures; page numbers ollowed by t re er to tables.

A Abdomen AP projection o , 65, 111 axial C images o , 382 cross-sectional image o , 298f, 323 le upper quadrant (LUQ), 335 regions o , 102 Abduction, 90 Absorption, 153, 154, 216, 391 Acid- ast bacillus (AFB) isolation, 17 Acquired immunode ciency syndrome (AIDS), 2, 16–17, 30, 378, 403 Acromioclavicular joints, 59, 65, 102, 108 Acromion process, 61, 61f, 106, 339 Acute radiation syndrome, 126, 139, 150 early symptoms o , 133, 159 Adduction, 46, 90, 111 Advance health care directive, 3, 18 “A er meals,” abbreviation or, 13, 31 Airborne precautions, 21–22, 23, 27, 32 Air– uid levels, demonstrating, 84, 108, 383 ALARA (as low as reasonably achievable) principle, 342 Alcohol-based hand sensitizers, 19 Aliasing (Moiré e ect), 331, 389 Alpha particles, 130, 154 Aluminum ltration, 133, 158, 164 Amorphous selenium (a-Se), 386 Ampoule, 17 Analgesic, 328 Analog images, 283 Analog-to-digital converter (ADC), 181, 209, 217, 223 Anaphylactic shock, 12 Anaphylaxis, 322, 327 Anemia, 385 Angina pectoris, 9, 26, 29, 404 Angulation, 85 Ankle AP projection o , 70, 113 AP stress studies o , 48, 92 lateral projection o , 60, 103 Ankle mortise, 39, 82 projections or, 88 Anode angle, 222, 230, 291 Anode, cracking o , 261, 278 Anode ocal track, pitting o , 279–280, 332 Anode heel e ect, 187, 198, 200f, 222, 223, 234, 236, 245, 287, 385, 389 Anoxic, 138, 165, 327 Antecubital vein, 317 Antibacterial medications, 28 Antibiotic, 328 Anticoagulant, 328 Anti ungal medications, 28 Antihistamine, 380 Antipyretic, 380

Antisepsis, 14, 32 Antiseptics, 28 A number Aorta, 72f, 115 Zygapophyseal joints, 323, 326, 342 Apophysis, 79, 94, 102 Appendicitis, 108 Apposition, 42, 85 Archival quality o lm, 391 ARR Code o Ethics, 15, 377 Arthritic changes in knees, evaluation o , 67, 110 Arthrography, 69, 117 Arti acts, 212, 214f, 228, 242, 244, 331, 338, 389 Asphyxia, 109 Aspirated oreign bodies, 48, 92–93 Aspiration, 66, 109 Assault, 28 Asthenic, 55, 99, 102 Asthma, 322 Asystole, 109 Atelectasis, 87, 109, 325 Atomic number, 134, 152, 154, 156–157, 160, 165, 186, 203, 207, 220, 221, 242, 246, 260, 263, 275, 276, 279, 292, 380 Atrial septal de ect, 28, 87 Atrial systole, blood ows during, 61, 104 Attenuation, 130, 153, 155, 180, 221, 246, 326, 391 Autoclaving, 24 Automatic brightness control, 261, 264, 277, 278 Automatic collimation, 278, 282 Automatic exposure control (AEC), 135, 161, 181, 187, 218, 241, 260, 261, 263, 269, 271, 273, 276, 278, 287, 291, 332, 367 Automatic lm processor, 245 Automatic implantable cardioverter de brillators (AICDs), 17 Autonomy, principle o , 27 Autotrans ormer, 267, 278, 281, 345 Avulsion racture, 46, 89 Axial trauma lateral (Coyle) position, 93, 120

Bell-T ompson scale, 73, 116 Benadryl (diphenhydramine hydrochloride), 380, 382 Bene cence, principle o , 27, 402, 403 Bergonié and ribondeau law, 127, 151, 153, 156, 165, 361 Bits, 215 Blood and body uid contamination, standard precautions or, 379 Blood ow, path o , 65, 108 Blood pressure, 396 equipment or measurement o , 10, 27 normal range, 20 units or measurement o , 10, 27 Blood urea nitrogen (BUN), 8, 70, 111, 114 normal range, 25, 32 Blowout ractures, 91, 117 Body habitus, 99, 106, 338, 371, 397 and gallbladder position, 102 Body mechanics, rules o , 305, 330–331 Body movements, 90 Body planes, 99, 100f Body substance precaution procedures, 328, 399 Bolus, 17, 18 Bone, 131, 156 Bone densitometry, 196, 231, 244, 285, 303, 329 Bone mineral density (BMD), 231 Bony thorax, 48, 92, 93f Boxes o x-ray lm, storage o , 218 Brachiocephalic artery, 76, 76f, 118 Brain, arteries supplying to, 71, 114 Breast tissue, in postpubertal adolescent, 70, 113 Bregma, 47, 90 Bremsstrahlung radiation, 136, 163, 259, 267f, 280, 386 Brightness, 154, 190, 202, 356 Bronchiectasis, 346 Bucky slot cover, 134, 145, 173 Bucky tray, 73, 116

B

C

Background radiation, 152 human-made, 150 natural, 130, 148, 150 Backup timer or AEC, 276, 278, 280 Ball-Catcher’s position, 61, 104 Barium enema (BE), 7, 214, 299, 377 Barium uorohalide, 217, 219, 297, 322, 323, 328, 346, 348 Barium sul ate contrast examination, 13, 30–31 Barium sul ate, oral administration o , 344 Barium sul ate suspension contraindications to, 71, 114 Base o support, 331, 381 Base-plus og, 339 Battery, 11, 28, 322 Battery-operated mobile x-ray units, 269, 289 Beam alignment, 227 Beam restriction, 142, 163, 170, 171, 247, 315 Beam restrictors, 168, 235, 278–279 Beam splitter, 264, 282 Becqueral, 174

Calcaneus, plantodorsal projection o , 118, 337 Caliper, 197, 234 Cannula, 116 Capacitance, 286 Capacitor-discharge mobile x-ray units, 289 Cardiogenic shock, 5, 21, 339 Cardiopulmonary resuscitation (CPR), or in ant, 395 Carotid arteries, 51, 95 Carpal bones, 56, 99 Carpal pisi orm ree o superimposition, projection or, 70, 114 Carpal tunnel syndrome, 334 Cassette–IR ront material, 191, 227 Cassettes, 244, 276, 278, 348 Cathartics, 20 Caudad, 114 Cecum, 87 Cells, undi erentiated, 361, 388 Central ray angulation, 57, 101 Central venous lines, 8, 24 Cephalad, 114

411

412

Index

Cervical spine anterior oblique position o , 62, 73, 105, 115 AP projection o , 63, 106 degree o anterior and posterior motion in, 382 degree o AP motion in, 73 lateral projection o , 37, 64f, 74, 107, 116 oblique projection o , 370, 394 radiograph, 99 Cesium iodide, 247, 260, 288 Characteristic curve, 237, 383 Characteristic radiation, 139, 166, 280 Charge-coupled device (CCD), 263, 281 Chemical og, 187, 313 Chest AP axial projection o , 301 inspiration and expiration projections o , 74, 117 lateral projection o , 42, 72, 85, 115 PA projection o , 50, 60, 93, 103, 195, 214f , 229 Chest radiography high kilovoltage, 210, 249 patient’s chin in, 50, 94 short exposure time or, 242 traumatic injuries and, 41, 84 Chest tubes, 24 Choke coil, 267, 286 Cholecystokinin, 70, 114 Chronic obstructive pulmonary disease (COPD), 325 Cigarette smoke as source o radon gas, 175 Cimetidine ( agamet), 379 Circuit, 262, 265, 267, 269, 278, 281, 283, 286, 289, 318, 345, 357, 358 383, 398, 405 Classic scatter, 151, 337 Clavicle AP projection o , 65, 107–108 axial projection o , 46 Coarctation o the aorta, 28, 87 Coccyx, AP projection o , 67, 98, 110 Colitis, 13, 31 Collar bone, 400 Colles’ racture, 66, 109 Collimators, 211, 250, 284, 285f, 292, 363, 391 Comminuted racture, 89 Compensating lter, 194, 230, 246, 389 Compound racture, 46, 89, 98 Compression, 251 o breast tissue, 211, 251 Compton scatter, 132, 139, 144, 151, 165, 172, 242, 291, 332–333, 337 Computed radiography (CR), 212, 232, 251, 274, 329, 348, 389 in anterior oblique position o cervical, 73, 116, 338 spine, 73, 116 image plates, 234 image with inverted IP, 190f, 216 or intercondyloid ossa, 376, 394 or lateral projection o barium- lled stomach, 64, 106 or lateral projection o larynx, 78, 120 or lateral projection o nasal bones, 74 or mandibular body in PA position, 76, 119 resolution in, 184, 220 Computed radiography/digital radiography (CR/ DR), 180, 216

Computed tomography (C ), 274 Cones, 280 Congenital megacolon. See Hirschsprung disease Congruence, 249, 264, 265, 274, 281, 283, 284, 292, 347, 367, 391, 394 Consent orm, 6, 22, 385–386 Contact isolation room, radiography in, 7, 24 Contact precautions, 1, 23, 27 Contaminated objects, cleaning guidelines or, 11, 28 Contrast agents miscibility o , 17 osmolality o , 2, 17 parenteral routes to administration o , 2, 17 reactions to acute renal ailure, 16 anaphylactic reaction, 16 vasomotor e ects, 1, 16 vasovagal reaction, 16 toxicity o , 17 viscosity o , 5, 17, 21 Contrast-improvement actor, 224 Contrast medium, 12, 27, 368, 404 Contrecoup injury, 47, 91 Contributory negligence, 6 Control badge, 387 Controlled area, 142, 169, 337 Conversion ef ciency, 220 Coracoid process, 77, 79, 120 Coronoid process, 49, 93 Cranium, bones o , 43, 86 Creatinine, normal range, 14, 32, 111 Crohn’s disease, 29 Cross-linking, 138, 165, 330 Crossover, 196, 245 C imaging system, 216, 244, 266, 274–275, 286– 287, 358, 383 C numbers, 203, 242, 252 C x-ray tube, 274–275, 284, 293 Current, 267, 286 Current, high- requency, 391 Cystogram, 324 Cystourethrogram, 324

Digital uoroscopy (DF), 281 Digital image, 232 contrast resolution o , 196, 232 ormation o , 215 Digital imaging, 259, 265, 277, 278 Digitalis, 404 Digital radiography (DR), 184, 219, 346 vs. CR, 389 Digitizer, 274 Dilantin, 404 Disease transmission, indirect modes o , 303 Disin ectants, 10, 19, 27–28 Distal, 71, 108 Distortion, 211, 248 Diuretics, 329, 339, 348 Divergence, 153 DNA irradiation, e ects o , 139, 141, 165, 169, 175 Dome o the acetabulum, 49, 94 Dorsal decubitus position, 395 Dose Area Product (DAP), 404 Dose creep, 217 Dose rate, 375 Dose–response curves, 135, 143, 156, 158, 163, 166, 172, 354 Double-contrast examination, 13, 23, 31, 52, 97 o large bowel, 61, 104 o stomach/large intestine, 52, 97 Double-contrast gastrointestinal (GI) series, 7, 23 Double exposure, 179, 216, 220 Double- ocus x-ray tubes, 374 Double-side-rail scission, 141 Droplet precautions, 11, 22, 23, 27 Dry desquamation, 155 Dual- eld image intensi er, 260, 276 Dual x-ray absorptiometry (DXA) imaging, 195, 205, 231, 266, 329 Dynamic range, 215 Dysphagia, 30, 345 Dysphasia, 403 Dysplasia, 378, 402 Dyspnea, 19, 20, 26 Dysrhythmias, drug or, 2, 16

D

E

DAC (digital-to-analog converter), 234, 335 “Dead man” switch, 129, 154 Decubitus position, 41, 42, 51f , 85, 95, 102 De amation, 11 De brillator, 2, 17 Densitometer, 197, 234, 265 Densitometry, 181, 245 Descending colon, 366f, 392 Detective Quantum Ef ciency (DQE), 187, 196, 213, 223, 232, 252 Developer unction o , 194, 229 under replenishment, 223 Detector element (DEL), 233, 235, 243 Dextrocardia, 40f, 83 Diarthrodial joints, 69, 113 Diarthrotic articulations, 54, 98 Diastolic pressure, 20 DICOM (Digital Imaging and Communications in Medicine), 380 Di erential absorption, 208, 241, 388, 389

E ective dose, 139, 150, 166 Elbow AP oblique projection o , 383 examination in partial exion, 379, 404–405 lateral oblique projection o , 65, 75, 108, 117 projection o , 64, 404–405 Elderly patients care o , 4, physical changes in, 26 Elective booking, 146, 174 Electroconductive, 188, 196, 205, 224, 232 Electrolysis, 276 Electrolytic method, 213, 252 Electromagnetic radiation, 155, 229 Electronic imaging, 98 Electronic timer, 390 Electrostatic ocusing lenses, 349, 392 Emergency and trauma radiography, 70, 113 Emetics, 339, 348 Emphysema, 8, 25, 39, 45, 81, 191, 209, 227, 248, 250, 306, 331, 348, 383, 393, 395

Index Endoscopic retrograde cholangiopancreatography (ERCP), 66, 76, 109, 300, 325, 372, 398 Entrance skin exposure (ESE), 384, 392 or average AP lumbar spine radiograph, 171 or average upright PA chest radiograph, 129 rom nomogram, 134, 145, 159, 173 Epilation, 130, 155 Epinephrine, 12, 16, 30 Epiphysis, 50, 92 Epithelial tissue, 381 Equipment operation and maintenance, 259–273 Errors in radiograph, 196, 196f, 234–235 Erythema, 130, 155, 169, 175 Erythroblasts, 138, 165 Esophageal varices, 44, 87, 400 Esophagram, 400 Ethmoidal sinuses, PA projection (Caldwell method) o , 49, 84 Evaluation criteria, or lateral projection o humerus, 46, 390 Ewing sarcoma, 59, 92, 102 Exostosis, 92, 346 Expiration, 77, 119 Exposure arti acts, 192, 192f, 199, 228 Exposure cords, 137, 163 Exposure dose, 163, 171 Exposure indicator, exposure index, 181, 217, 328 Exposure latitude, 228 Exposure rate, 221 and SID, 193, 228 Exposure rate or examination, 125, 148 Exposure time, 393 reducing o , 191, 227 Exposure-type arti acts, 192 Extravasation, 6, 23, 340 Eye gear (goggles), 8, 25

F Facial bones, 65, 108–109 Facsimile transmission o health in ormation, 4, 20 False imprisonment, 322 Fat pads, in elbow lateral projections, 37, 79 Female patients, and radiation protection, 135, 161 Femoral neck, 72, 115, 401 AP axial projection o , 68, 111 Femur, 45, 60, 88, 88f, 103, 402 Fetal anomalies, 156 Fidelity, principle o , 27, 402, 403 Field o view (FOV), 154, 185, 187, 220, 224, 233, 328 Field size decreasing o , 193, 229 restriction o , 174, 334, 390 and scattered radiation amount, 135, 161 Filament, 163, 246, 264, 268, 269, 282, 283, 284, 286, 289, 297, 332, 347, 357, 358, 374, 394, 400, 405 Film age, 219 Film badge, 137, 152, 159 Film box, expiration date, 218 Film density, 219 Film emulsion, 208, 246, 251 Film og, 183, 207, 219, 246 Filmless radiography, 322 Filters, used in radiography, 136, 163

Filtration, 129, 141, 142, 153, 169, 170, 175, 284, 391 Flat contact shields, 160 Flat-panel detectors, 386 Fluorescence, 248 Fluorescent light, emission o , 221, 247 Fluoroscopic image, brightness o , 262, 286, 289, 337, 388 Fluoroscopic skin dose, 383 Fluoroscopy, radiation sa ety in, 131, 156 Focal-spot blur, 191, 226–227, 237, 342 Focal-spot size, 208, 225, 237, 275 Focal-spot size accuracy, 222, 237 Focal track, 264, 265f, 276 Focusing distance, 200, 235 Fomite, 3, 6, 18, 22, 30 Foot bones o , 310f, 343 dorsoplantar projection o , 57, 100 lateral projection o , 44, 76, 87, 118 medial oblique projection, 95 Forearm anterior view o , 401 lateral projection o , 57, 100–101, 391 Foreshortening, 182, 190, 218, 225 Fowler position, 102 Fractionation, and radiation dose e ects, 137, 163 Freezing, 25 Frontal and ethmoidal sinuses, PA axial Caldwell position, 401 Full-wave recti cation, 275, 285 Full-wave-recti ed single-phase equipment, 284 Fuse, 280

G Gadolinium oxysul de, 208, 247, 273, 292 Gas-producing powder, ingestion o , 7, 23 Gauge, 12, 29, 306, 332 Gender, as risk actor or breast cancer, 74, 117 Generators, high- requency, 385 Genetically signi cant dose (GSD), 139, 146, 166, 175, 364, 391 Genetic e ects o radiation, 169, 170 Geometric blur, 186, 211, 221, 222 Geometric unsharpness, 248, 250, 307, 333, 354 Geriatric patients, 14, 32 Gestation, 142, 169 GI radiography, stomach position, 63, 106 GI tract, radiosensitive portion o , 129, 153,171 Glenohumeral joint, 46, 77, 89, 120 Glenoid ossa, positioning or, 391 Gloves, latex, 18 Gonadal cells, human, 143 Gonadal shielding, 126, 134, 160, 306, 332 types o , 130, 155 use o , 126, 149 Gout, 92 Grashey method, 370, 391, 396 Greater tubercle, demonstration o , 68f, 111 Green-sensitive lm, 247 Grid, 224, 235, 242, 243, 244, 247, 248 high-ratio, 201 and radiographic contrast, 224 and scattered radiation, 184, 216 use o , 251 Grid, 16:1, 367, 397 Grid centering errors, 198, 198f

413

Grid cuto , 195, 224, 230, 232, 362f, 385, 391 Grid interspace material, 180, 192, 315 Grid lines, 242 Grid ratio, 185, 186, 208, 219, 220, 221, 234, 243, 247, 248, 398 Grieving process, stages in, 5 Guide shoe, 206, 207f, 245

H Hal -value layer (HVL), 128, 132, 157, 159, 160, 195, 230, 277, 284, 335 Hand in extension, lateral projection, 43, 86 oblique projection o , 41, 84–85 PA oblique projection o , 87 and wrist, PA projection, 334 Hand hygiene, 4, 19, 30 Handling and storage arti acts, 228 Health Insurance Portability and Accountability Act (HIPAA), 402 Heat units (HU), 274, 277, 291, 292 Heel e ect, 234, 268, 271, 292, 364, 391 Heavy object, moving o , 6, 23 Helical C , 387 Health Level-7 (HL-7) Hematemesis, 341 Hematuria, 341 Hemoptysis, 52, 96 Heparin, 343, 356, 382 Heparin lock, 25 Hepatic exure, 62, 104, 398 Hepatitis B virus (HBV), transmission o , 2, 17 Hesitation marks, 245 Hiatal hernia, 72, 115 High- requency generators, 301, 327 High-speed lm/screen imaging systems, 136, 245 Hilus, 44, 87 Hip, axiolateral projection o , 66, 109 Hirschsprung disease, 353, 380 Histogram, 297, 323, 329, 380, Honor Code violations, document on, by ARR , 15 Hospital-acquired in ections (HAIs), 20–21, 25, 387 Hospital In ormation Systems (HIS), 233, 402 Human immunode ciency virus (HIV) entry sites, 357, 384 transmission o , 16 Human-made radiation, 150 Houns eld Unit (HU), 203, 212, 242, 252 Hydronephrosis, 52, 95–96 Hyperbaric therapy, 148 Hypersthenic, 62, 67, 105, 110–111 Hypertension, 6, 32, 116, 346 actors or, 73, 116 Hypochlorite bleach (Clorox), 10, 27 Hypodermic, 18 Hypoglycemic reactions, 336 Hypovolemic shock, 21, 339 Hypoxic, 327 Hysterosalpingography, 49, 94, 109

I Iatrogenic in ection, 1, 16 Idiopathic, 376, 401 Ileocecal valve, 58, 102 Ileus, paralytic, 55, 98

414

Index

Iliac crest, 62, 105 Image acquisition and evaluation, 179–253 Image contrast, 220 Image density, 370 Image distributor, 329, 358 Image, in ormation on, 1, 15 Image intensi cation, 369 Image intensi ers, 261, 280 brightness gain o , 269, 288 Image intensi er’s input phosphor, 267, 273, 292, 344 Image-intensi er tubes, 289 Image magni cation, 225 Image procedures, 37–120 Immature cells, 129, 153 Impulse timer, 390 Induction motor, 268, 287 In ection, cycle o , 2, 11, 28, 314, 341 In ection, stages o , 19 In ectious microorganisms, transmission o , 30 In erior articular process, vertebra, 76f, 119, 119f In ammatory bowel disease, 11, 30 In uenza, 11, 29 In ormed consent, 385–386 In raorbitomeatal line (IOML), 396 Inherent ltration, 264, 267, 282 Innominate bone, 75, 118 Inspiration, 11, 28 and radiographic density, 105 Intensi ying screen phosphors, 328 Intensi ying screens, 243, 346, 368, 392, 401 Intensi ying screen speed, 392 Intentional misconduct, 4 , 20, 361, 388 Intercondyloid ossa, 53f, 97 methods or demonstration o , 41, 84 Interphalangeal joints, 401 Intertrochanteric crest, 378, 402 Intertubercular (bicipital) groove, 336 Intervertebral oramina, 42, 86, 325 Intervertebral joints, 74, 116, 399 Intramuscular injections, needle angle or, 5 Intrathecal injection, 43, 86 Intravenous (IV) needle, gauge number, 16 Intravenous pyelogram (IVP), 27 Intravenous urogram (IVU), 69, 70, 111, 113, 214f, 253, 334, 395 Intussusception, 65, 108 Invasion o privacy, 1, 15, 20, 342, 388 Inverse-square law o radiation, 133, 151, 162, 166, 171, 172, 173, 323, 330, 387 Iodinated contrast medium, side e ects o , 4, 23 Ionization, 133, 159 Ionization chamber, 134, 160, 278 Ionizing radiation detection o presence o , 144, 172, 174 direct e ect, 149, 167 indirect e ect, 126, 149, 167 late e ects o , 130, 171, 298, 324 somatic e ects, 127, 150 and target theory, 149, 167 Irradiation o macromolecules, 138, 165 Isotopes, 131, 134, 1156–157, 161 IV in usion, 8, 18, 25 IV push, 18 IV urography, 56

J Jaw-thrust method, or airway opening, 18 Judet method, right acetabulum, 40, 83 Jugular notch, 75, 117

K Kilovoltage (kVp), 157, 160, 183, 195, 206, 220, 230, 235, 249, 347 decrease in, 220 increase in, 180, 192, 199, 216, 229, 235 and primary beam, 132, 157 and radiographic contrast, 221 and scattered radiation, 221 Knee AP projection o , 42, 94, 331, 335 lateral projection o , 52, 96 mediolateral projection o , 313, 354f Knee joint, 42, 72, 116 Knee-joint space, visualization o , 63, 63f Knee x-ray arthrography, 74, 117 Kubler-Ross, Elizabeth, 5, 20 Kyphotic curve, 58, 102

L Laminae, 54, 98 Lanthanum oxybromide, 247 Laryngeal prominence, 69, 113, 120 Larynx, lateral projection o , 78, 120 Lasix ( urosemide), 380 Latent image, 217, 344 Lateral, 109 Lateral border, scapula, 61, 61f, 105 Latex, medical equipment, 3, 18 Latitude, 204, 251 Lead aprons, 129, 144, 153, 165, 169, 175, 341, 401, 403 Lead rubber mat, 396 Leakage radiation, 131, 144, 152, 156, 173 Le vertebral artery, 76, 76f, 119 Legg–Calvé–Perthes disease, 27 Lesser tubercles, 89, 336, 390 Levin tube, 8, 24 Lidocaine, 16, 343, 382 Light-shield layer, 232 Linear dose–response curve, 163, 170 Linear energy trans er (LE ), 130, 150, 155, 162, 337, 378, 404, and biologic response, 365, 391 and RBE, 132, 135, 158, 162 Linearity, 226, 328 Linear, nonthreshold dose–response curve, 155, 162, 171, 172 Linear threshold dose–response curve, 155–156, 162, 166, 171 Line- ocus principle, 237, 245, 288, 338, 339, 391 Line pairs per millimeter (lp/mm), 182, 218 Line spread unction (LSF), 182, 218, 349, 385 Lithium uoride chips, 172 Lithium uoride crystals, 127, 152 Living will, 3, 18 Logrolling, 10 Long bones, 50 Longitudinal arch, oot, 313 Look-up table (LU ), 202, 358 Lordotic curve, 102

Low- ow oxygen delivery, 401 LPO position, 300f, 326 Lumbar articular acets projection, 50, 94 Lumbar puncture, 397 Lumbar spine AP projection o , 101, 325 lateral projection o , 86 LPO projection o , 400 oblique projection o , 71, 71f, Lumbosacral zygapophyseal articulation, 56, 99 Luminescence, 133, 159, 216 Luxation, 85 Lymphocytes, 125, 149, 339, 403 Lysol, 10, 27

M Magnetic resonance imaging (MRI), 274 contraindication to, 9, 26 patients screening be ore, 57, 101 Magni cation actor (MF), ormula or, 231 Magni cation radiography, 208, 223, 248, 270, 289–290, 319, 346, 347 Main-chain scission, 138, 165, 330 Mammography, 262, 278, 368, 394, 399 quality control in, 197, 197f, 233 Mandible, 56, 116 Mask, use o , 391 Maslow hierarchy o basic human needs, 372 Mass number, 134, 157, 161 Matrix size, and image resolution, 197, 220 Maxillary sinuses, 49, 119 Mechanical obstruction, in neonates, 9, 26 Medial, 115 Medial displacement o a tibial racture, 51 Medial malleolus, 369f, 395 Medial oblique projection, o elbow, 42f, 86 Metaphysis, 58, 102 Metastatic survey, 24 Met ormin hydrochloride (Glucophage), 41, 84 Midcoronal plane, 56, 87, 99, 100f, 371f, 397 Midsagittal plane, 99, 100f, 371f, 397 Milliampere-seconds (mAs), 183, 201, 225, 226, 233–234, 238, 239, 240 calculation o , 233–234 and exposure rate, 186, 221 ormula or, 218 and radiographic density, 226 Minimum response time, 291 Misalignment, 85, 179, 248, 391, 404 Mobile radiographic equipment, and radiation protection, 141, 168, 271 Modality Work List (MWL), 202, 241, 374, 384, 399 Modulation trans er unction (M F), 160 Moist desquamation, 155 Molybdenum ocusing cup, 279, 282, 288, 348 Mosaicked, 221–222, 225 Motion control o , 194, 230 e ect on recorded detail, 273 unsharpness, 182, 218, 344, 359, 386 Motion blur, 212f, 252 Motor, 262, 278 Mottle, 221 Moving grids, and stationary grids, 265, 283 MRSA precautions, or radiographer, 9, 27

Index Multiple myeloma, 348 Muscular dystrophy, 27 Mutual induction, 383 Myelogram, 43, 86 Myelography, 65, 70, 108, 114, 286 contrast medium in, 46, 69, 90, 112, 112f, 398–399

N Nasal cannula, 401 Nasal septum, parietoacanthal projection, 72, 115 Nasogastric (NG) tubes, 8, 24 National Council on Radiation Protection and Measurements (NCRP) on annual occupational whole-body dose equivalent limit, 135, 148, 150, 158, 175, 291, 339, 386 on total equivalent dose limit to embryo/ etus, 419 Needles, contaminated, 373, 403 Negative contrast agent, 201, 239 Nephrotomography, 110 Nerve cells, 339 Neurogenic shock, 21, 339 Neurons, 129 Nitroglycerin, 12, 16, 29, 30, 343 Nonionic, water soluble contrast media, advantages o , 9, 26 Nonlinear threshold dose–response relationship, 137, 163, 169 Nonmale cence, 378, 402, 403 Nonstochastic e ects, 148, 324, 341 Norepinephrine, 343 Norgaard method, 61, 104

O Objective data, 382 Object-to-image distance (OID), 335 and recorded detail, 199 and SID, 208, 248 and size distortion, 218, 225 Obstructed bowel, 243 Obturator oramen, 67, 110 Occupancy actor, 159 Occupational dose limit, 129, 154, 404 or students, 145, 168 Occupational radiation monitoring, 126, 138, 150, 155, 158 Occupational Sa ety and Health Administration (OSHA), 299, 325 Odontoid process, 107 O -center errors, 235 O - ocus errors, 234 O - ocus radiation, 269, 289 Olecranon ossa, 305f, 331 Olecranon process, 64, 107 Operative cholangiography, 64, 106 Optical density, 300 Optically stimulated luminescence (OSL) dosimeter, 134, 137, 146, 163, 164, 167,174 Organ doses, 164, 171, 393 Orthopnea, 382 Orthoroentgenography, 73, 116 Orthostatic hypertension, 382 Os calcis, plantodorsal projection o , 60, 118 Osgood–Schlatter disease, 47, 92

Osteochondritis, 27, 229 Osteoma, 346 Osteomalacia, 393 Osteomyelitis, 229 Osteoporosis, 193, 229 Osteosclerosis, 229 Oxygen delivery, 6, 27 Oxygen supply, inadequate, symptoms o , 13, 31

P Pacemaker, 24 PA chest radiograph, 48, 48f, 93 Parallel line–type resolution test pattern, 278, 279f Paranasal sinuses, 63, 94 PA axial projection o , 63, 106, 376 radiography o , 75 Parenteral routes, 346, 357, 384 Parietoacanthal (Waters method) projection, 72, 108–109, 115 Parkinson disease, 195, 231 Pasteurization, 24–25 Patella, tangential projection o , 60, 64, 103, 107 Patello emoral articulation, 40f, 82 Patent ductus arteriosus, 87 Patient as scatterer, 140, 169, 399 Patient care, 1–33 in eeling o aint, 10, 27 with IV line, 11, 29 physical assistance and trans er, 4, 6, 19 Patient dose, 392 exposure actors and, 132, 143, 157, 169 actors e ecting, 132, 155 during uoroscopy, 262, 278, 331 and FOV, 130, 155 high-speed intensi ying screens and, 141, 169, 184 reducing o , 136, 163 Patient history objective data, 31 subjective data, 13, 31 Patient postings, 174 Patient preparation or lower gastrointestinal series, 68, 111 or upper gastrointestinal series, 66, 109 or upper GI examination, 14, 39 Patient protection, guidelines or, 174 Patient questionnaire, 174 Patient’s bill o rights, 349 Patient’s medical record, 6, 21 right to review, 26 Pediatric patients radiography o , 169 restraining, 66, 109 Pedicles, 43f, 86 Pelvis emale, 79 male, 79 Penetrometer, 285 Percutaneous transluminal angioplasty (P A), 66, 109 Peripherally inserted central catheter (PICC), 24, 109 Personal radiation monitor reports, 402 Phosphorescence, 209, 248 Photocathode, 161, 280, 349 Photodetector, 223

415

Photoemissive, 236, 239, 250, 280, 286, 289, 292, 336, 344, 349, 392, 409 Photoelectric e ect, 128, 132, 136, 146, 150–151, 154, 154f, 163, 165, 166, 174, 241, 291, 332–333, 337, 338 Photoelectric interaction, 175 Photon, 219, 251 Photostimulable phosphor plate, 273, 293, 322, 323 Photostimulable phosphor (PSP), 181, 217 dust/dirt particles on, 222 Photostimulated luminescence (PSL), 217, 249 Phototimer, 161, 262, 278, 285, 287, 289, 372 Picture archiving and communication system (PACS), 265, 283 Pi lines, 245 Pinhole camera, 222 Pixel size, 191, 220 in digital imaging, 196, 232 Pneumonia, 325, 346 Pneumoperitoneum, 243 Pneumothorax, 325, 348 Pocket dosimeter, 142, 166–167, 170, 172 Point lesions, 138, 165, 304 Polyps, 13, 31, 345 Port-a-Cath, 24 Positioning or axillary ribs, 44, 87 elbow at pads, 52, 96 or rst two cervical vertebrae in AP projection, 75, 105 or proximal tibio bular articulation, 51, 95 sesamoid bones o oot, 47, 92 o shoulder, 89 Positive contrast agent, 353 Postmicturition (postvoiding) radiograph, 395 Postprocessing, 183, 217, 218, 229, 232, 249, 264, 281, 287, 367, 380, 383, 394 Pregnancy irradiation during, 144, 146, 152–153, 173, 399 radiation protection or personnel, 125, 148, 152–153 Primary radiation barriers, 132, 137, 159, 163, 339 Principle o sel -induction, 286, 385 Processing algorithm, 200, 228, 237, 238, 240, 297, 329, 353, 380, 383 Processing arti acts, 228 Pro essional ethics, 10, 27 Prominence o the greater trochanter, 89 Prone recumbent projection, 58f, 101 Protective apparel, leaded, 389 Protective curtain, 147, 175, 325 Protective devices, and scattered radiation, 127, 159–160 Protective or reverse isolation, 12 Proximal, 99, 114 Pulmonary artery, 378, 403 Pulmonary embolism, 44, 87 Pulmonary vascular markings, 392 Pulse, 66, 110 Pulse rate, determination o , 1, 27t Pulsed radiation, 284, 386 Pyelogram, 7, 24

Q Quality assurance (QA), 134, 159, 191, 226, 243 Quality-control (QC) program, 263, 278, 328

416

Index

Quantum detection ef ciency (QDE), 220 Quantum mottle, 196, 245, 248

R Rad, 130, 155, 174 Radial head circum erence, demonstrating, 69, 111–112 Radial styloid process, 72 , 115 Radiation dose, 396 Radiation e ects on body, actors impacting, 150, 162, 171 Radiation exposure early e ects o , 156, 324 hematologic e ects o , 156 late e ects o , 156, 363, 390 long-term somatic e ects o , 139, 166 reducing o , 141, 162, 169 (See also Primary barriers; Secondary barriers) Radiation-induced leukemia, 136, 162 Radiation-induced tissue damage, 137, 164 Radiation protection, 125–175 Radiation protection guidelines or occupationally exposed, 151, 161 Radiation quality, 170 Radiation sa ety of cer (RSO), 142, 170 Radiation weighting actors, 127, 140 Radiographer ethical obligation o , 19 personal radiation sa ety objective, 145, 169 pregnant, 138, 165, 172, 174, 403 Radiographic contrast, 199, 202, 221, 235–236, 241, 361, 388, 392 changes in kilovoltage and, 388–389, 388f actors e ecting, 199, 235 Radiographic density, 222 actors or, 187, 222 intensi ying screen speed and, 187, 222 and SID, 193, 230, 245 Radiographic lm processing order, 192, 228 Radiographic rating charts, 270f, 277, 290, 324, 398 Radiograph, underexposure o , 251 Radiology In ormation Systems (RIS), 202, 233, 240, 380 Radiolucent contrast agents, 380 Radiolucent sponge, placement o , 46, 89 Radiolysis, 126, 150 Radiopaque contrast agents, 380 Radiopaque objects, 265, 283 Radioresistant cells, 153 Radiosensitive cells, 123, 127, 131, 138, 149, 151, 156, 165, 171, 393, 403 Radiosensitive tissues, 146, 175, 396 Radon exposure, 147, 175 RAO position, 367, 384, 393 Rare earth phosphors, 247, 275, 292 Receptor exposure, 181, 184, 196, 201, 202, 204, 208, 211, 219, 247, 248, 252, 330 Reciprocity law, 199, 235, 334 Recoil electron, 332 Recorded detail and SID, 401 Recti cation, 260, 275–276, 289, 405 Recti ers, 285 Reducers, 209 Regional enteritis, 108

Relative biologic e ectiveness (RBE), 392 Rem, 128, 152, 163, 174 Renal colic, 243 Reproducibility, 226, 328 Reproductive cells, and ionizing radiation, 141, 172 Res ipsa loquitur, 335 Resistance, 286 Resolution, 218, 222, 250, 349 Respiration rate, normal, 12, 30 Respiratory isolation, 341 Respiratory structures, 38, 93, 106, 305 Respondeat superior, 18, 335 Retrograde pyelogram, 298, 324 Retrograde urography, 67, 110, 386, 398 Retroperitoneal structures, 384–385 Rheostat, 270, 398 Ribs below-diaphragm, 75, 118 Right scapular Y, 91 Right upper quadrant (RUQ), structures in, 70, 114 Roentgen, 134, 137, 145, 155, 303, 329 Rotation distortion, 324 Rotor, 268, 287

S Sacroiliac joints, 70, 78, 113, 120, 400 Sacrum, AP axial projection o , 98 Sagittal plane, 397 Salem-sump tube, 8, 24 Scaphoid, in PA oblique projection, 355, 381 Scapula AP projection o , 75, 118, 299f, 324 lateral projection o , 59 , 62, 102–103, 106 posterior aspect o , 61f, 105 Scapular Y projection, 46, 56, 89, 99, 102, 117 Scattered radiation, 151, 152, 230, 241–242, 388–389 e ects o , 181, 230 intensity o , 142, 160 production o actors e ecting, 190, 226 limiting, 188, 211, 251 Scattered radiation og, 361, 388 Scattering, 129, 153, 155, 216, 391 Scoliosis examinations, 69, 220 “Scotty dog” image, 91, 95, 95f, 400 Screen– lm contact, poor, 201, 201f, 238, 244, 251 Secondary radiation, 127, 151–152 Secondary radiation barriers, 141, 157, 168, 339 Sensitometry, 159, 234 Septic shock, 339 Shadow shields, 160 Shaped contact shields, 160 Shape distortion, 179, 190, 209, 218, 225, 326, 248, 378, 404 elongation, 326 oreshortening, 326 Shock, symptoms o , 14, 32 Shoulder AP, external rotation projection o , 77, 120 AP projection o , 67, 97, 99, 111 internal rotation projection o , 68, 111 Shoulder arthrography, 74

Signal-to-noise ratio (SNR), 394 Silver halide, 209, 249 Silver reclamation, 213 Sim position, 102 Single-contrast barium enema (BE), 74 Single-phase equipment, 284 Single-side-rail scission, 141 Skin discoloration, due to cyanosis, 10, 26 Skin entrance exposure (SEE), 171 Skull AP axial projection o , 40, 67, 110 baselines in positioning o , 73, 73 , 116, 119 images with di erent contrast, 189f, 224 lateral projection o , 69, 101, 112 PA projection o , 38, 62, 80, 105, 132, 157, 399–400 submentovertical (SMV) projection o , 59, 73, 102, 116 Slip ring technology, 387 Slit camera, 200, 222, 237, 262, 278 Solid-state diodes, 262, 278, 285 Somatic e ects o radiation, 141, 166, 169 Source-to-image distance (SID), 181, 206, 217, 225, 226, 228, 268, 288, 331 and exposure rate and radiographic density, 204, 238, 298, 324 impact on x-ray photon intensity, 133, 158 and size distortion, 218, 225 and skin dose, 136, 162 Source-to-skin distance (SSD) and ESE, 143, 171 in mobile uoroscopy, 135, 161 Spatial resolution, 215, 262, 276 Spermatids, 339 Sphenoidal sinuses, 75, 118 Sphygmomanometer, 14, 31, 345 Spinning top test, 272, 273, 284, 291–292, 293 Spinous process, 42f, 100 Splenic exure, 398 Spondylolisthesis, 40, 84 Sprain, 85 Star and wye con guration, 264, 282, 282f Star pattern, 222 Static electricity, 244 Stator, 266f, 268, 277, 278, 282 Stent, 66, 109 Step wedge, 290 Sterile techniques, or contrast media administration, 369, 396 Sterilization, methods o , 8, 24–25 Sternal angle, 44, 87 Sternoclavicular articulations, 41, 85 Sternoclavicular joints, 75, 93, 360, 389 Sternum, 389 rontal view o , 40, 84 in RAO position, 106 Stethoscope, 14, 32, 345 Stochastic e ects, o radiation exposure, 131, 156, 314, 341 Streptococcal pharyngitis (strep throat), 371, 397 Subarachnoid space, 46, 90 Subcutaneous emphysema, 393 Subjective data, 382 Super cial arteries, 1, 15 Superior vena cava, 70, 113 Swan–Ganz catheter, 7, 24

Index Synchronous spinning top test, 273, 284, 386 Synchronous timer, 390 Syncope, 12, 29 Synovial pivot articulations, 47, 111 Systolic pressure, 20

T abletop exposure rate, 144, 172 alipes, 10, 27 alocalcaneal joint, 39, 60, 103 alo bular joint, medial oblique projection o , 65, 108 angential patella, 80 angential (sunrise) projection, 386 arget theory, 146, 174 arsal navicular, 67, 369f arsometatarsal joints, 57, 100 echnique charts, 378, 403 EDE limit, annual, or radiation worker, 315, 342 10-day rule, 174 T ermionic emission, 268, 276, 287, 289, 347 T ermoluminescence, 133, 164 T ermoluminescent dosimeter ( LD), 134, 140, 144, 146, 152, 167, 168, 171, 174, 384 T in lm transistor ( F ), 230, 235, 243, 386 T ompson scatter, 151, 337 T oracic vertebra, 103 T ree-phase current, 367, 393 T ree-phase equipment, 272, 289, 346 T yroid dose rom AP skull projection, 137, 164 ibio emoral joint, 115 issues densities, and x-ray absorption, 156 issue weighting actors, 127, 140, 150, 167 omography, 264, 281, 290 ort, 11, 28 liability in, 309, 335 orus racture, 89 racheostomy, 11 rans ormers, 286, 385 high-voltage, 267, 286, 289, 345, 385 ransverse plane, 99, 100f, 371f, 399 rapezium, 72f, 115 and rst metacarpal articulation, 63, 106 raumatic injury

to hip, imaging precautions, 68, 91 to upper extremity, imaging considerations, 52, 96 raumatic spine injury patient, imaging o , 64, 107 ree static, 244 rendelenburg position, 12, 30, 59, 102 rimalleolar racture, 71, 114 rochlea, 46, 90, 90f -tube cholangiography, 404 ungsten alloy, 280, 306, 331–332 V camera tubes, 282 V monitor, 282 ylenol (acetaminophen), 380

U Ulcerative colitis, 108 Ulnar exion/deviation, 54, 97 Umbra, 186 Unconscious patient, examination o , 5, 20 Uncontrolled area, 169, 337 Upper gastrointestinal (GI) examination, 39 Upside-down ocused grid, 240–241 Urinary Foley catheter bag, placement o , 4, 19 Urticaria, 10, 27 Use actor, 133, 159

V Varus, 79 Vasogenic shock, 21 Vector, 30, 329 Ventral decubitus position, 395 Ventricular septal de ect, 28, 87 Veracity, principle o , 10, 27, 402, 403 Verapamil, 16 Vertebra, 97–98, 97f, 103, 119, 119f Vial, 2, 17 Vital signs assessment o , 13, 31 normal ranges or, 27t Voiding cystourethrogram (VCUG), 65, 107 Voltage, 286 Voltage ripple, 263, 280 Voxel, 187, 221, 223, 225

417

W Water-soluble iodinated media, use o , 12, 30 Wavelength 180, 193, 202, 211, 219, 228, 229, 230, 251, 276, 300, 304, 329, 382 Wheelchair ootrests, position o , 5, 20 Whole-body dose, 391 calculation o , 137, 164 Whole-body radiation, 126, 165 Wilm’s tumor, 70, 113 Windowing, 182, 218, 220, 380 Window level (WL), 185, 196, 202, 218, 220, 226, 232–233, 261, 358, 383 Window width (WW), 185, 202, 218, 220, 233, 240, 277, 356, 383 Wire mesh test, 238 Workload, 159

X X-radiation, diagnostic, 126, 150 X-ray arthrography, 74, 117 X-ray beam e ective energy o , 265, 287, 355, 382 restriction o , 133, 152 X-ray lm components o , 313, 339 emulsion, 208, 246 processing o , 230 X-ray images, in ormation on, 323 X-ray photons, 261, 282 energy o , 183, 220 production o , 273, 284 X-ray tubes, 262, 274–275, 333, 345, 382 damage to, 264 ailure o , 367, 394 grid-controlled, 279 li e, extending, 306, 379, 405, 284 X-ray tube targets, construction o , 236, 245, 288, 259, 339

Y Yellow marrow, long bone, 45, 88

Z Z number, 128, 223–224 Zygomatic arches, 53f, 73, 97, 116, 388

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Attenuation Characteristics of Lead Aprons

ARRTSTANDARDSOFETHICS

X-ray attenuation at

ARRT standards of ethics are composed of the following:

Pb Equivalent Thickness (mm)

75 kV (%)

100 kV (%)

66 88 99

51 75 94

0.25 0.50 1.0

• Code of ethics (aspirational) • Rules of ethics (enforceable)

CONDITIONSFORVALIDPATIENTCONSENT • • • •

PRIMARYBARRIERS • Protect from the useful/primary beam

e patient must be of legal age e patient must be of sound mind e patient must give consent freely e patient must be adequately informed of the procedure about to take place

FACTORSININFECTIONTRANSMISSION/CYCLEOFINFECTION SECONDARYBARRIERS • Protect from scattered and leakage radiation

RADIATIONPROTECTIONCARDINALRULES

1. 2. 3. 4. 5. 6.

An infectious organism/pathogen A reservoir of infection and environment for pathogen to live and multiply A portal of exit from the reservoir A means of transmission A susceptible host A portal of entry into the susceptible new host

• Time • Distance • Shielding

Oral

TRADITIONALANDSI EQUIVALENTS

Parenteral

METHODSOFDRUGADMINISTRATION • PO (by mouth), enteric/through digestive system

• • • • •

–4

1 R = 2.58 × 10 C/kg 1 J/kg = 1 Gya 1 rad = 100 ergs/gm = 0.01 Gyt 1 rem = 0.01 Sv = 0.01 J/kg

Topical Subcutaneous Intradermal Intramuscular Intravenous Grid Ratio

ORIGINOFSCATTEREDRADIATIONANDMETHODS FORCONTROLLINGITSPRODUCTION •

e larger the x-ray eld size, the more scattered radiation produced Solution: Collimate • e higher the kilovoltage, the greater the production of scattered radiation (a result of the higher incidence of Compton scatter interactions) Solution: Use optimum kilovoltage • e thicker and more dense the body tissues, the greater the amount of scattered radiation produced Solution: When possible, compression of the part or use of the prone position to decrease the e ect of fatty tissue

• • • • • •

mAs Conversion Factor 1 2 3 4 5 6

No grid 5:1 6:1 8:1 10/12:1 16:1

GRIDCONVERSIONFORMULA mAs1 Conversion factor1 = mAs2 Conversion factor2

Inverse-Square Law Formula

• To determine the new exposure rate/dose:

Correction Factors Single Phase

Three Phase

χ mAs

2/3 χ for 3φ (6p)

χ mAs

1/2 χ for 3φ (12p) and HF

χ kV

χ –12% for 3φ and HF

I1 D 22 = I 2 D12

Exposure Maintenance Formula

• To maintain receptor exposure: mAs1 D12 = mAs2 D 22

ANODEHEELEFFECT e anode heel e ect is emphasized under the following conditions:

• At short source-to-image receptor distances • With large image receptors • With small anode angles

Heat Unit Formula HU = mA × s × kV (single phase)

Heat Unit Formula with Three-Phase Correction Factor

• HU = mA × s × kV (single phase) • HU = mA × s × kV × 1.4 (three phase and high frequency)

ASGRIDRATIOINCREASES • • • •

Scattered radiation cleanup increases and contrast resolution improves Contrast scale decreases in SF imaging Exposure factors (usually mAs) must increase Positioning latitude decreases

Filtration Requirements

• < 50 kVp = 0.5 mm Al equiv • 50–70 kVp = 1.5 mm Al equiv • > 70 kVp = 2.5 mm Al equiv