Radiography PREP Program Review and Exam Preparation, 8e (2015) [8 ed.] 0071834591, 9780071834599

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PROGRAM REVIEW AND EXAM PREP

REVIEWERS

RADIOGRAPHY

PREP EDITION

8 D. A. Sa ia , MA, RT(R)(M) Rad io g rap hy Ed u cato r an d Co n su ltan t Ad ju n ct Pro fe sso r, Co n co rd ia Co lle g e Bro n xville, Ne w Yo rk

New York Chicago San Francisco Athens London Madrid Milan New Delhi Singapore Sydney Toronto

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Copyright © 2015 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: 978-0-07-183459-9 MHID: 0-07-183459-1 The material in this eBook also appears in the print version of this title: ISBN: 978-0-07-183458-2, MHID: 0-07-183458-3. 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. 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Dedicated Spiritus Sancti gratia, illuminet sensus et corda nostra.

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Reviewers Gloria A. Albrecht, MS, RT(R) Program Director; School of DiagnosticImaging Cleveland Clinic Euclid, Ohio Deanna Butcher Program Director School of DiagnosticImaging St. Cloud Hospital St. Cloud, Minnesota Gail Faig, BS, RT(R)(CV)(CT) Clinical Coordinator School of RadiologicTechnology Shore Medical Center Somers Point, NewJersey Jayme A. Frangione, BA, RT(R) RadiologicTechnologist Stamford Hospital Stamford, Connecticut Merryl N. Fulmer, BS, RT(R)(M)(MR)(QM)(CT) Program Director School of RadiologicTechnology Shore Medical Center Somers Point, NewJersey Brenda Grant, RN, MPH, CIC, CHES Manager, Infection Prevention Stamford Hospital Stamford, Connecticut Paula R. McPeak, MSRS, RT(R)(M) Program Director RadiologicTechnology Riverside College of Health Careers Newport News, Virginia Eugene T. Rodda, AB, RT(R) RadiologicTechnologist Hospital for Special Surgery Stamford, Connecticut Daniel Sorrentino, MS, RT(R) RadiographyProgram Director Concordia College Bronxville, NewYork

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REVIEWERS

Robert Wells, MEd, RT(R)(CT) Program Director, RadiologicTechnology Lanier Technical College Oakwood, Georgia Ingrid Wright, MHSc, RT(R) Program Director RadiologicTechnologyProgram St. Johns River State College Palatka, Florida

Contents Preface.....................................................................................................................................................ix Acknowledgments....................................................................................................................................xi Master Bibliography................................................................................................................................xiii

I. PATIENTCAREANDEDUCATION............................................................1 1. Legal and Ethical Aspects..........................................................................................3 Chapter ReviewQuestions....................................................................................................12 2. Patient Communication and Safety...................................................................... 15 Chapter ReviewQuestions....................................................................................................30 3. Infection Control .........................................................................................33 Chapter ReviewQuestions....................................................................................................44 4. Patient Monitoring, Medical Emergencies, and Pharmacology............................... 47 Chapter ReviewQuestions....................................................................................................71

II. IMAGINGPROCEDURES................................................................. 75 5. General Procedural Considerations....................................................................... 77 Chapter ReviewQuestions....................................................................................................90 6. Imaging Procedures: Anatomy, Positioning, and Pathology................................... 93 Chapter ReviewQuestions..................................................................................................213

III. RADIATIONPROTECTION..............................................................227 7. Radiation Protection Considerations................................................................... 229 Chapter ReviewQuestions..................................................................................................250 8. Patient Protection ............................................................................................. 253 Chapter ReviewQuestions..................................................................................................270 9. Personnel Protection ......................................................................................... 273 Chapter ReviewQuestions..................................................................................................283 10. Radiation Exposure and Monitoring ................................................................... 287 Chapter ReviewQuestions..................................................................................................298

IV. IMAGEACQUISITIONANDEVALUATION..........................................301 11. Technical Factors and Image Quality................................................................... 303 Chapter ReviewQuestions..................................................................................................384 12. Image Processing and Quality Assurance ............................................................ 389 Chapter ReviewQuestions..................................................................................................409 13. Image Evaluation: Digital and Screen–Film ........................................................ 411

V. EQUIPMENTOPERATIONANDQUALITYCONTROL...........................435 14. Radiographicand Fluoroscopic Equipment.......................................................... 437 Chapter ReviewQuestions..................................................................................................500 15. Standards of Performance and Equipment Evaluation......................................... 503 Chapter ReviewQuestions..................................................................................................512 16. Practice Test ...................................................................................................... 517 Index

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Preface Radiography PREP (Program Review and Examination Preparation), eighth edition, is intended to be useful throughout all phases of radiography education. The text is designed to be useful for regular coursework, helping the student to extract fundamental key concepts from reading assignments and class notes, and for making study and test preparation easier and more productive. PREP is also useful for students preparing for their American Registry of Radiologic Technologists (ARRT) certification examination. It helps students direct their study efforts toward examination-related material and includes registry-type multiple-choice questions designed to help students practice test taking and critical thinking skills they will need for the ARRT radiography examination—and for their professional careers. The ARRT’s Content Specifications for the Examination in Radiography lists the examination’s five content categories and provides a detailed list of the topics addressed in each category. Radiography PREP is divided into five parts reflecting each of the five content categories. Part content reflects changes to the ARRT Content Specifications published in January 2013 and implemented in January 2014. Some basic introductory CT material is also included—an area becoming increasingly important for the entry-level radiographer. As this field continues to grow, there is increasing emphasis on its inclusion in the radiography curriculum. Particularly important is updated and expanded information on Digital Imaging. Thus, study becomes even more directed and focused on examination-related material. A series of tools are available for effective coursework study followed by preparation for the certification test. PREP and Radiography Review Flashcards are recommended for use with regular coursework. Used with their companion book, Lange Q&A Radiography Examination, PREP and Radiography Review Flashcards provide a thorough preparation for the certification examination administered by the ARRT. Finally, certification examination preparation can be extended to include the computerized testing offered at the web site www.RadReviewEasy.com.

KEYFEATURESANDUSE • More than 400 illustrations and images appeal to the visual learner as well as the verbal learner. The essence of radiography is visual and PREP’s graphics and radiographic images visually express the written words. • The numerous summary boxes serve to call the student’s attention to the most important facts in a particular section. Students can use summary boxes as an overview of key information. • Inside covers list a number of formulae, radiation protection facts, conversion factors, body surface landmarks, digital imaging facts, acronyms, and abbreviations, radiation quality factors, and minimum

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PREFACE

filtration requirements. A “last-minute cheat sheet” is provided for some things that students often forget because they may not use them on a regular basis. • The final review sections allow students to assess chapter material in two ways. The first review section, Comprehension Check, requires short essay answers; exact page references follow each question, providing answers in chapter material. The second section, Chapter Review Questions, consists of registry-type multiple-choice questions followed by detailed explanations. To make the most of their study efforts, students are encouraged to review in that order: Comprehension Check first, followed by the multiple-choice questions. • Chapter 14 (Equipment) includes a section on Computed Tomography. As this field continues to grow, there is increasing emphasis on its inclusion in the radiography curriculum. • Chapter 16 is a practice test; a simulation of the actual certification examination with questions designed to test your problem-solving skills and your ability to integrate facts that fit the situation. The questions are designed to provide focus and direction for your review, thus helping you do your very best on your certification examination. Chapter review questions can be supplemented using Radiography Review Flashcards of the same content. Following completion of the chapter review questions, radiography flashcards, and the practice test, the student is ready for final self-evaluation by answering more “registrytype” questions in the companion text, Lange Q&A the Radiography Examination, Tenth Edition, and supplemental study at its web site www.RadReviewEasy.com.

Acknowledgments I appreciate having the opportunity to thank those who have most generously contributed their insights, talents, and concerns to this project. Foremost among those are my teachers and colleagues who have contributed to my knowledge over the years and the many students on whom I have had the privilege of sharpening my knowledge and skills. I greatly appreciate the friendship, encouragement, and support generously offered by my former colleagues Olive Peart, MS, RT(R)(M) and Teresa Whiteside, BA, RT(R)(BD), (CDBT). I am grateful to the professional staff of McGraw-Hill for their guidance through this project, with special notes of appreciation to, Andrew Moyer, Christina Thomas, Midge Haramis, Catherine A. Johnson, and Aptara project manager Amit Kashyap for their creativity, support, and patience in bringing this text to publication. A special note of appreciation goes to Andrew Moyer for his support in the development of Radiography Review Flashcards. Another thank you goes to Jennifer Pollock for her development and maintenance of the books’ companion web site, www.RadReviewEasy.com. Andrew’s and Jennifer’s foresight and expertise have brought successful added dimensions to both texts—PREP and the Q&A. Everyone at McGraw-Hill has been helpful in the development of these projects; it is always a pleasure to work with their creative and skilled staff. An outstanding group of reviewers was recruited for this edition of PREP. Gloria Albrecht, Deanna Butcher, Gail Faig, Jayme Frangione, Merryl Fulmer, Brenda Grant, Paula McPeak, Gene Rodda, Dan Sorrentino, Robert Wells, and Ingrid Wright are all invaluable resources to the health care and the radiologic imaging communities. They reviewed the manuscript and offered suggestions to improve style and remove ambiguities and inaccuracies. Their participation on this project is deeply appreciated. A particular thank you goes to Carissa Pietzsch, Global Marketing Communications Coordinator at Fluke Biomedical for her speedy and kind attention to my last-minute permission request. A special thank you is extended to David Sack, BS, RT(R), CRA, FAHRA for permission to use several images from his excellent teaching file. Another thank you goes to Nathan M. Sokolowski, CFI Sales Manager-East, Eastern US, Canada, EU/ME/Africa for his assistance in providing photographs of the Zero Gravity lead shielding system. Mr. Sokolowski and CFI Medical, Fenton Michigan, were most helpful and accommodating. Grateful appreciation goes out to Doug Lofting and his helpful staff, Tami and Carol, at Shielding International for permission to use images of their protective devices and providing PDF files of the images. Another note of thanks goes to Roger Flees, RT (retired), Inside Sales Manager of Philips Healthcare, Dunlee Division. Thank you, Roger, for generously sharing your time and expertise. Our discussions and your follow-up emails were most helpful. Your help in obtaining permission for use of tube rating charts is appreciated. xi

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ACKNOWLEDGMENTS

I would like to thank the American College of Radiology for the use of radiographs from their teaching file and Stamford Hospital’s Department of Radiology for permission to use many of their x-ray images. I also extend my appreciation to Conrad P. Ehrlich, MD, for granting permission to use several radiologic images; Dr. Ehrlich and his staff at Housatonic Valley Radiological Associates have been most helpful. The CT section in Chapter 14 could not have been accomplished without the help of several individuals. For answering questions, providing images, and reviewing material, I am grateful to Sarah Bull, MS, DABR, Angie Dohan, RT(R), Conrad Ehrlich, MD, Paula Hill, RT(R) (CT)(CV)(M), Doug Schueler, RT(R)(CT), and Teresa Whiteside AS, RT(R)(BD), (CDBT). Several people were helpful in securing permission and providing photographs for illustration. Special thanks go to Landauer Inc, especially Judith Mangan, for providing and granting permission to use their dosimeter graphics; Mr. Dick Burkhart at Burkhart Roentgen and Mr. Artie Swayhoover at Nuclear Associates were all very helpful and supportive. The preparation of this text would have been a far more difficult task without the help and encouragement of my husband, Tony. His enduring understanding, support, assistance, and advice are lovingly appreciated.

Master Bibliography On the last line of each answer/explanation, there appears the last name of the author or editor of one of the publications listed here, along with a number or numbers indicating the correct page or range of pages where information relating to the correct answer may be found. Adler AM, Carlton RR. Introduction to Radiologic Sciences and Patient Care, 4th ed. St. Louis, MO: Elsevier Saunders, 2007. Adler AM, Carlton RR. Introduction to Radiologic Sciences and Patient Care, 5th ed. St. Louis, MO: Elsevier Saunders, 2011. ASRT Code of Ethics. http://www.asrt.org/content/RTs/CodeofEthics/Code_Of_Ethics. aspx. Accessed on November 2, 2014. BEIR Report VII. www.nap.edu/openbook.php?isbn=030909156x. Bontrager KL, Lampignano JP. Textbook of Radiographic Positioning and Related Anatomy, 7th ed. St. Louis, MO: Mosby, 2010. Bontrager KL, Lampignano JP. Textbook of Radiographic Positioning and Related Anatomy, 8th ed. St. Louis, MO: Elsevier Mosby, 2014. Bushong SC. Radiologic Science for Technologists, 9th ed. St. Louis, MO: Elsevier Mosby, 2008. Bushong SC. Radiologic Science for Technologists, 10th ed. St. Louis, MO: Elsevier Mosby, 2013. Bushberg JT, Seibert JA, Leidholdt EM, Boone JM. The Essential Physics of Medical Imaging, 2nd ed. Baltimore, MD: Lippincott Williams & Wilkins, 2002. Carlton RR, Adler AM. Principles of Radiographic Imaging, 4th ed. Albany, NY: Delmar, 2006. Carlton RR, Adler AM. Principles of Radiographic Imaging, 5th ed. Albany, NY: Delmar Cengage, 2013. Dowd SB, Tilson ER. Practical Radiation Protection and Applied Radiobiology, 2nd ed. Philadelphia, PA: WB Saunders, 1999. Ehrlich RA, Coakes DM. Patient Care in Radiography, 8th ed. St. Louis, MO: Elsevier Mosby, 2013. Fosbinder RA, Kelsey CA. Essentials of Radiologic Science, 1st ed. McGraw-Hill, 2002. Fosbinder R, Orth D. Essentials of Radiologic Science. Baltimore, MD: Lippincott Williams & Wilkins, 2012. Frank ED, Long BW, Smith BJ. Merrill’s Atlas of Radiographic Positioning and Procedures, Vols 1, 2, and 3, 11th ed. St. Louis, MO: Mosby, 2007. Frank ED, Long BW, Smith BJ. Merrill’s Atlas of Radiographic Positioning and Procedures, Vols 1, 2, and 3, 12th ed. St. Louis, MO: Elsevier Mosby, 2012. Fuji Medical Systems. CR Users Guide, Stamford, CT: FUJIFILM Medical Systems USA, Inc, 2004. Hendee WR, Ritenour ER. Medical Imaging Physics, 4th ed. New York, NY: Wiley-Liss, Inc, 2002. Mills WR. The relation of bodily habitus to visceral form, tonus, and motility. Am J Roentgenol 1917; 4:155–169. NCRP Report No. 99. Quality Assurance for Diagnostic Imaging. NCRP, 1990. NCRP Report No. 116. Recommendations on Limits for Exposure to Ionizing Radiation. NCRP, 1987. NCRP Report No. 160. Ionizing Radiation Exposure of the Population of the United States. NCRP, 2009. xiii

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Romans, LE. Computed Tomography for Technologists, A Comprehensive Text. Philadelphia, PA: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2011. Saladin KS. Anatomy and Physiology, The Unity of Form and Function, 7th ed. New York, NY: McGraw-Hill, 2015. Seeram E. Digital Radiography: An Introduction for Technologists. Clifton Park, NJ: Delmar Cengage Learning, 2010. Selman J. The Fundamentals of Imaging Physics and Radiobiology, 9th ed. Springfield, IL: Charles C. Thomas, 2000. Shephard CT. Radiographic Image Production and Manipulation, 1st ed. New York, NY: McGraw-Hill, 2003. Sherer MAS, Visconti PJ, Ritenour ER. Radiation Protection in Medical Radiography, 6th ed. St. Louis, MO: Mosby Elsevier, 2011. Sherer MAS, Visconti PJ, Ritenour ER, Haynes KW. Radiation Protection in Medical Radiography, 7th ed. St. Louis, MO: Mosby Elsevier, 2014. Tortora GJ, Derrickson B. Principles of Anatomy and Physiology, 12th ed. Hoboken, NJ: John Wiley & Sons, Inc, 2009. Venes D, ed. Taber’s Cyclopedic Medical Dictionary, 20th ed. Philadelphia, PA: F. A. Davis, 2005. Wolbarst AB. Physics of Radiology, 2nd ed. Madison, WI: Medical Physics Publishing, 2005.

PART

I

Patient Care and Education

CHAPTER 1 Legal and Ethical Aspects Patient’s Rights Patient Privacy Patient Consent Bill o Rights/Patient Care Partnership Legal Issues X-Ray Examination Requests Law/Medicolegal Issues Standards of Ethics ARRT® Standards o Ethics Honor Code

CHAPTER 2 Patient Communication and Safety Communication with Patients Verbal/Written and Nonverbal Communication Explanation o Procedure Explanation o A tercare Communication Challenges Cultural and Other Medical Terminology Techniques to Improve Communication Evaluating Patient Condition Physical Signs Vital Signs Physical Assistance and Transfer Body Mechanics Patient Trans er Trans er Conditions Requiring Special Attention

CHAPTER 3 Infection Control Terminology and Basic Concepts Microorganisms Medical and Surgical Asepsis Hand Hygiene Personal Care Cycle of Infection Pathogens Reservoir o In ection Portal o Exit Susceptible Host Portal o Entry Modes o Transmission Standard Precautions In ection Control Basic Guidelines Healthcare-Associated In ections Transmission-Based Precautions Airborne Droplet Contact Patients Whose Immune Systems Are Compromised Contaminated Material Disposal

CHAPTER 4 Patient Monitoring, Medical Emergencies, and Pharmacology Routine Monitoring Vital Signs Physical Signs/Symptoms Documentation

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Patient Support Equipment Oxygen Suction Intravenous Equipment and Venipuncture Tubes Allergic Reactions Side E ect Versus Toxic E ect Latex Contrast Media Terminology and Basic Concepts Scheduling and Preparation Considerations Contraindications and Patient Education Pharmacology, Reactions, and Emergency Situations Other Medical Emergencies Vomiting Fractures

Spinal Injuries Epistaxis Postural Hypotension Vertigo Syncope Convulsion Seizure Unconsciousness Acute Abdomen Shock Respiratory Failure Cardiopulmonary Arrest Stroke

Legal and Ethical Aspects

1

Ethics re ers to a set o principles o right and wrong behavior, a system o values that guides conduct in relationships among people in accordance with particular expected patterns o behavior. Ethical conduct is particularly important in the healthcare pro essions. T e e ects o our actions and/or behavior can harm others, put them at risk or harm, or violate their rights.

OBJECTIVES At the conclusion o this chapter, the student will be able to: • Discuss Ethics relative to behavior and values, and their relationship to the healthcare pro essions. • Identi y the acronym HIPAA and discuss that legislation’s impact on patient in ormation. • Identi y the purpose o an Advance Care Directive and its impact on patient autonomy and decision-making. • Discuss the radiographer’s responsibilities regarding patient examination requests. • List examples o potential pro essional negligence. • List the parts o the ARR Standards o Ethics. • Identi y where guidelines or the radiographer’s pro essional conduct can be ound.

PATIENT’SRIGHTS Patient Privacy Most institutions now have computerized, paperless systems to accomplish in ormation transmittal; these systems must ensure conf dentiality in compliance with Health Insurance Portability and Accountability Act (HIPAA) o 1996 regulations. T e healthcare pro essional generally has access to the computerized system only via personal password, thus

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PART I PATIENT CARE AND EDUCATIO N

Ethical Behavior

•

The e ects o our actions and/or behavior can harm others, put them at risk or harm, or violate their rights.

helping 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. All healthcare practitioners must recognize that their patients comprise a community o people o all religions, races, and economic backgrounds, and that each patient must be a orded their best e orts. Every patient should be treated with consideration o his or her worth and dignity. Patients must be provided conf dentiality and privacy. T ey have the right to be in ormed, to make in ormed consent, and to re use treatment.

Patient Consent

Conditions for Valid Patient Consent

• • • •

The patient must be o legal age. The patient must be o sound mind. The patient must give consent reely. The patient must be adequately in ormed o the procedure about to take place.

Patient consent can be verbal, written, or implied. For example, i a patient arrives or emergency treatment alone and unconscious, implied consent is assumed. A patient’s previously granted or presumed consent can be withdrawn at any time. Written patient consent is required be ore any examination that involves greater than usual risk, or example, invasive vascular examinations requiring the use o injected iodinated contrast agents. For lower risk procedures, the consent given on admission to the hospital is generally su cient. It is imperative that the radiographer takes adequate time to thoroughly explain the procedure or examination to the patient. An in ormed patient is a more cooperative patient, and a better examination is more likely to result. Patients should be clear about what is expected o them and what to expect rom the radiographer. T is must be considered the standard o care or each patient, to ul ll not only legal mandates, but also pro essional and humanistic obligations.

Bill of Rights/Patient Care Partnership T e American Hospital Association’s (AHA) Management Advisory presented a Patient’s Bill o Rights that was rst adopted by the AHA in 1973, then revised and approved by the AHA Board o rustees in October o 1992. T e 1992 Patient’s Bill o Rights detailed 12 speci c areas o patients’ rights and the healthcare pro essional’s ethical (and o en, legal) responsibility to adhere to these rights. T e Patient’s Bill o Rights was summarized as the right to 1. 2. 3. 4. 5. 6. 7. 8. 9.

considerate and respect ul care; be in ormed completely and understandably; make decisions about plan o care/re use treatment; have an advance directive (e.g., a living will, healthcare proxy) describing the extent o care desired; privacy; con dentiality; review his or her records (access to his/her healthcare in ormation); request appropriate and medically indicated care and services; know about institutional business relationships that could inf uence treatment and care;

CHAPTER 1 LEGAL AND ETHICAL ASPECTS

10. be in ormed o , consent to, or decline participation in proposed research studies; 11. continuity o care; 12. be in ormed o hospital policies and procedures relating to patient care, treatment, and responsibilities. T e AHA recently replaced the Patient’s Bill o Rights with T e Patient Care Partnership—Understanding Expectations, Rights, and Responsibilities. T eir plain-language brochure includes the essentials o the Bill o Rights and reviews what patients can/should expect during a hospital stay. T e Patient Care Partnership statement addresses high-quality hospital care—combining skill, compassion, and respect and the right to know the identity o caregivers, whether they are students, residents, or other trainees. It includes a clean and sa e environment, ree rom neglect and abuse, and in ormation about anything unexpected that occurred during the hospital stay. T e Patient Care Partnership identi es involvement in your care; it elaborates on patient discussion/understanding o their condition and treatment choices with their physician, the patient’s responsibility to provide complete and correct in ormation to the caregiver, and understanding who should make decisions or the patient i the patient cannot make those decisions (including “living will” or “advance directive”). T e Patient Care Partnership statement also identi es protection o your privacy—describing the ways in which patient in ormation is sa eguarded. It also describes help when leaving the hospital—availability o and/or instruction regarding ollow-up care. Finally, the Patient Care Partnership statement addresses help with your billing claims—including ling claims with insurance companies, providing patient physicians with required documentation, answering patient questions, and assisting those without health coverage. T e above-mentioned patient rights can be exercised on the patient’s behal by a designated surrogate or proxy decision maker i the patient lacks the decision-making capacity, is legally incompetent, or is a minor. Many people believe that potential legal and ethical issues can be avoided by creating an Advance Health Care 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 Health Care Directive, or Living Will, names the individual 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.

LEGALISSUES It is essential that radiographers, like other healthcare pro essionals, be amiliar with their Practice Standards published by the American Society o Radiologic echnologists (ASR ). T e Standards provide a legal role def nition and identi y Clinical, Quality, and Pro essional Standards o practice— each Standard has its own rationale and identi es general and speci c criteria related to that Standard. T e student radiographer can access the individual Standards, their rationale, and criteria on the ASR website.

The Patient Care Partnership What to expect during your hospital stay: 1. High-quality hospital care 2. A clean and sa e environment 3. Involvement in your care 4. Protection o your privacy 5. Help when leaving the hospital 6. Help with your billing claims Source: The American Hospital Association.

Advance Health Care Directive/ Living Will

•

Preserves a person’s right to make decisions regarding their own health care

•

Names the individual authorized to make all healthcare decisions or them

•

Can include speci cs regarding DNR, DNI, and other end-o -li e decisions

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PART I PATIENT CARE AND EDUCATIO N

X-Ray Examination Requests

Tort

• • •

A private/civil injustice Reparation can be sought Is either intentional or unintentional

X-ray examinations are typically requested by a physician or physician’s assistant. Request orms or radiologic examinations must be care ully reviewed by the radiographer prior to commencement o the examination. Many hospitals and radiology departments have speci c rules about exactly what kind(s) o in ormation must appear on the requisition. 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 identif ers. Rigorous observance o “timeout” processes prior to procedures can avoid costly events, including those involving patient identi cation. It is important that the radiographer obtain a short but adequate, pertinent patient history o why the examination has been requested. Because patients are rarely examined or interviewed by the radiologist, observations and in ormation obtained by the radiographer can be a signi cant help in making an accurate diagnosis. T e radiographer must be certain to obtain all clinical in ormation in a manner and environment that ensures patient privacy. T e requisition is usually printed with the patient’s personal in ormation (name, address, age, 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. T e radiographer must be certain to understand and, i necessary, clari y the in ormation provided, or example, any abbreviations used and any vague terms such as leg or arm ( emur vs. tibia, humerus vs. orearm). T e radiographer must also be alert to note and clari y conf icting in ormation, or example, a request or a le ankle examination when the patient complains o , or has obvious injury to the right ankle. Computerized systems or department policy may require that there be appropriate and accurate diagnostic in ormation accompanying every request or diagnostic procedure.

Law/Medicolegal Issues T e our primary sources o law are the Constitution o the United States, statutory law, regulations and judgments o administrative bureaus, and court decisions. T e Constitution expresses the categorical laws o the country. Its impact with respect to health care and healthcare pro essionals lies, in part, in its assurance o the right to privacy. T e right to privacy indicates that the patient’s modesty and dignity will be respected. It also re ers to the healthcare pro essional’s obligation to respect the con dentiality o privileged in ormation. Communication o privileged in ormation to anyone but the appropriate healthcare pro essionals is inexcusable.

CHAPTER 1 LEGAL AND ETHICAL ASPECTS

Statutory law re ers to laws enacted by congressional, state, or local legislative bodies. T e en orcement o statutory laws is requently delegated to administrative bureaus such as the Board o Health, the Food and Drug Administration, or the Internal Revenue Service. It is the responsibility o these agencies to enact rules and regulations that will serve to implement the statutory law. Court decisions involve the interpretation o statutes and various regulations in decisions involving individuals. For example, the decision o an administrative bureau can be appealed and the court would decide i the agency acted appropriately and correctly. Court decisions are re erred to as common law. T ere are two basic kinds o law: public law and private (civil) law. Public laws are any that regulate the relationship between individuals and government. Private, or civil, law includes laws that regulate the relationships among people. Litigation involving a radiographer’s proessional practice is most likely to involve the latter. A private (civil) injustice, injury, or misconduct is a tort, and the injured party may seek reparation or damage incurred. orts are described as either intentional or negligent/unintentional. Examples o intentional (misconduct) torts include alse imprisonment, assault and battery, de amation, and invasion o privacy. False imprisonment is the illegal restriction o an individual’s reedom. Holding a person against his or her will or using unauthorized restraints can constitute alse imprisonment. Assault is to threaten harm; battery is the carrying out o the threat. A patient might eel su ciently intimidated to claim assault by a radiographer who threatens to repeat a di cult examination i the patient does not try harder to cooperate. A radiographer who per orms an examination on a patient without his or her consent, or a er the patient has re used the examination, can be guilty o battery. A charge o battery may also be made against a radiographer who treats a patient roughly or who per orms an examination on the wrong patient. A radiographer who discloses con dential in ormation to unauthorized individuals can be ound guilty o invasion o privacy. A radiographer whose disclosure o con dential in ormation is in some way detrimental to the patient (e.g., causing ridicule or loss o job) can be accused o de amation. Spoken de amation is slander; written de amation is libel. T e assessment o duty (what should have been done) is determined by the pro essional standard o care (that level o expertise generally possessed by reputable members o the pro ession). T e determination o whether or not the standard o care was met is usually made by determining what another reputable practitioner would have done in the same situation. Medical malpractice lawsuits are principally initiated based on the negligence theory o liability, that is, ailure to use reasonably prudent care. 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. T e term malpractice is usually used with re erence to negligence. T ree areas o requent litigation in radiology involve patient alls and positioning injuries, pregnancy, and errors or delays in diagnosis.

For Negligent Tort Liability, Four Elements Must Be Present

• • • •

Duty (what should have been done) Breach (deviation rom duty) Injury sustained Cause (as a result o breach)

Negligence

•

Medical malpractice lawsuits are principally initiated based on the negligence theory o liability.

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Legal Doctrines

• •

Res ipsa loquitur—“the thing speaks or itsel ” Respondeat superior—“let the master answer”

Patient alls and positioning injuries. Examples: A sedated patient le unattended in the radiographic room alls rom the x-ray table; a patient with a spinal injury is moved rom the stretcher to the x-ray table, resulting in irreversible damage to the spinal cord. Pregnancy. Example: T e radiographer ails to inquire about a possible pregnancy be ore per orming a radiologic examination. Sometime later, the patient contacts the healthcare acility, expressing concern about the etus. Errors or delays in diagnosis. Example: T e patient undergoes an x-ray examination in the emergency department and is sent home. T e radiologist interprets the images and ails to noti y the emergency department physician o the ndings. T e physician gets a written report 2 days later. Meanwhile, the patient su ers permanent damage rom an untreated condition. 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/caregiver’s actions, it becomes the radiographer’s/caregiver’s burden to disprove negligence. Examples o this include imaging the wrong patient/incorrect limb, surgical removal o a healthy organ or limb, leaving a sponge or clamp in a patient’s body a er surgery. In many instances, the hospital and/or radiologist will also be held responsible according to respondeat superior, or “let the master answer.” T e “master,” or employer, can be held liable or wrong ul acts o the “servant,” or employee, in causing injury during employed activities.

STANDARDSOFETHICS T e mission o the American Registry o Radiologic echnologists (ARR ) is to promote high standards o patient care by recognizing quali ed individuals in medical imaging, interventional procedures, and radiation therapy. As every radiography student knows, the ARR develops and administers examinations that assess the knowledge and skills underlying the intelligent per ormance o the tasks typically required by pro essional practice in the modality. In addition, the ARR adopts and upholds • standards or educational preparation or entry into the pro ession • standards o pro essional behavior consistent with the level o responsibility required by pro essional practice Practitioners o the pro ession o radiologic technology, like other healthcare pro essionals, have an ethical responsibility to adhere to principles o pro essional conduct and to provide the best services possible to the patients entrusted to their care. T ese principles are detailed in the ARR two-part Standards o Ethics, which includes the Preamble, the Code o Ethics (Part A), the Rules o Ethics (Part B), and the Administrative Procedures. T e 10-part Code o Ethics is aspirational; the 22 Rules o Ethics are en orceable and any violation can result in sanction/injunction. T e complete ARR Standards o Ethics was last revised and published on September 1, 2014 and can be ound on the ARR website. All student radiographers preparing or ARR certi cation and ARR certied technologists should be amiliar with this important document.

CHAPTER 1 LEGAL AND ETHICAL ASPECTS

ARRT® Standards of Ethics T e student should be completely amiliar with the ARR Standards o Ethics. Situations can occur that make us wonder what the “right” thing to do is—circumstances that require us to make ethical decisions. T e Standards o Ethics provides guidelines or making these very important decisions; the decision we make could impact our entire pro essional career. T e ARR Ethics Committee provides peer review o cases to ensure adherence to standards o pro essional behavior. Radiographers, like all healthcare providers, must have the moral character required to practice in the healthcare pro essions. I their actions demonstrate that moral character is lacking, that individual can be sanctioned. T e sanction can be in the orm o a reprimand, a suspension o registration, revocation o registration, ineligibility or certi cation, or other sanctions deemed appropriate by the Ethics Committee. T e student should care ully study the ARR Rules o Ethics. For example, i you become aware that one o your coworkers is in violation o one o the Rules o Ethics, what must you do? Your pro essional obligation is to report your knowledge to your supervisor, then to the ARR (according to Rule #21, you are in violation i you ail to report to the ARR ), and you must report to the State i your State has licensing. T e radiographer must remember that ailure to disclose a conviction is a violation o Ethical Rules #1 and #19 and involves alsi cation o ARR in ormation. ARR can become aware o an unreported conviction as part o an employment background check. T is could actually result in a more serious sanction than the original o ense! T e radiographer needs to be amiliar with the ARR Standards o Ethics, as they provide very important in ormation and answers to tough questions that can be encountered during the course o the radiographer’s pro essional practice.

Honor Code T e word honor implies an e ective regard or the standards o one’s pro ession, a re usal to lie or deceive, an uprightness o character or action, a trustworthiness and incorruptibility that is, being incapable o alling short in a trust or responsibility. Other words used to describe these qualities are honesty, integrity, and probity. Certainly these are qualities required o students and healthcare proessionals. 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. All candidates or primary, post primary, and continuing pathway ARR certi cation must meet ethical/honor code requirements. T e ARR Rules o Ethics indicate that elonies, misdemeanors, and various criminal procedures must be reported. Any primary pathway candidates may use the pre-application process to determine their ethics eligibility be ore enrolling in a radiography program, or any time during the program. Many educational programs have their particular Honor Code to which students are required to adhere. I a student has been suspended or dismissed/expelled rom a (any) radiography program, that incident must be indicated on the ARR

ARRT Standards of Ethics Composed of

• • • •

Preamble Code o Ethics (aspirational) Rules o Ethics (en orceable) Administrative Procedures

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application, submitted with a detailed explanation and with accompanying documentation. A student radiographer having any question regarding a violation reportable on their ARR examination application should contact the ARR Ethics Requirements Department. A radiographer (or student radiographer) convicted o a misdemeanor or elony must report that to the ARR . T e Ethics Committee will conduct a peer review o the case and make a determination regarding possible sanction. One important consideration will be i the actions were job related and could present a risk to the wel are o the patient.

Summary • Patient consent can be verbal, written, or implied; a valid patient consent includes our conditions. • Hospital In ormation Systems must ensure con dentiality in compliance with Health Insurance Portability and Accountability Act (HIPAA) o 1996 regulations. • T e AHA Patient’s Bill o Rights details 12 speci c areas o patient rights that the healthcare pro essional is obligated to respect. • T e AHA has replaced the Patient’s Bill o Rights with the six-part Patient Care Partnership. • An Advance Health Care Directive, or Living Will, names the individual authorized to make all healthcare decisions and can include speci cs regarding DNR, DNI, and/or other end-o -li e decisions. • T e healthcare worker has primary responsibility or checking/ veri ying patient identity, most acilities require checking at least two patient identi ers. • T e ASR Practice Standards identi es the level o knowledge and skill required o a pro essional radiographer. • Radiologic examinations may be requested by a physician or physician’s assistant. • T e radiographer should examine the requisition care ully be ore bringing the patient to the radiographic room. • Most healthcare acilities require that examination requests include pertinent diagnostic in ormation and any in ection control or isolation in ormation. • A civil injustice is a tort; a tort can be intentional or negligent. • Negligence litigation in radiology most requently involves injuries rom alls, positioning injuries, pregnancy, and errors or delays in diagnosis. • T e ARR Standards o Ethics consists o a Preamble, the Code o Ethics, the Rules o Ethics, and the Administrative Procedures. • T e Code o Ethics details guidelines or the radiographer’s pro essional conduct and is aspirational. T e Rules o Ethics are mandatory and en orceable. • All candidates or primary pathway/continuing ARR certi cation must meet ethical/honor code requirements.

CHAPTER 1 LEGAL AND ETHICAL ASPECTS

COMPREHENSION CHECK Congratulations! You have completed this chapter. I you are able to answer the ollowing group o comprehensive questions, you can eel con dent that you have mastered this section. You are then ready to go on to the “Registry-type”multiple-choice questions that ollow. For greatest success, do not go to the multiple-choice questions without rst completing the short-answer questions below.

7. List the conditions necessary or valid consent (p. 4). 8. Discuss public versus private (civil) law (p. 7). 9. Di erentiate between assault and battery, slander and libel (p. 7). 10. Give examples o intentional and unintentional torts (p. 7, 8).

1. To what does the term ethics re er? How/why is ethical behavior important in the healthcare pro essions (p. 3, 4)?

11. List the our elements o a negligent tort (p. 7).

2. What are the two parts o the ARRT Standards o Ethics? Which part is mandatory and en orceable (p. 8, 9)?

13. Identi y the areas o litigation that most requently involve radiology (p. 8).

3. How can Honor Code violations impact a candidate or an ARRT examination (p. 9,10)? 4. Discuss the AHA Patient’s Bill o Rights with respect to legal considerations pertinent to radiography and relate it to the new AHA Patient Care Partnership (p. 4, 5). 5. Describe an Advance Health Care Directive and possible elements that it might address. What is its purpose (p. 5)? 6. Discuss the purpose o the ASRT Practice Standards or the radiographer (p. 5).

12. Medical malpractice lawsuits are principally initiated based on what theory o liability (p. 7, 8)?

14. List the patient in ormation usually ound on examination request orms (p. 6). 15. To what does the acronym HIPAA re er (p. 3)? 16. Describe the impact o the 1996 HIPAA regulations on radiologic patient care considerations (p. 3, 4). 17. Identi y the kinds o clari cation that may be required be ore beginning the x-ray examination (p. 6). 18. Review the ARRT Rules o Ethics and give an example o how one or more could impact a radiography student (p. 9).

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CHAPTER REVIEW QUESTIONS 1. The ASRT document that de nes the radiographer’s role is the:

6. Patients’rights include the ollowing: 1. The right to re use treatment

(A) Standards o Ethics

2. The right to con dentiality

(B) Practice Standards

3. The right to possess one’s medical records

(C) Standard o Care

(A) 1 only

(D) Legal Standards

(B) 1 and 2 only

2. Occurrences that can keep a radiography student rom meeting ARRT certi cation requirements include: 1. Being suspended rom a radiography program 2. Being dismissed/expelled rom a radiography program 3. Failing more than one course in their radiography program (A) 1 only (B) 2 only (C) 1 and 2 only (D) 1, 2, and 3 3. Violations o the ARRT Rules o Ethics include:

(C) 1 and 3 only (D) 1, 2, and 3 7. A radiographer who per orms an x-ray examination on a patient without the patient’s consent, or a ter the patient has re used the examination, may be liable or: (A) Assault (B) Battery (C) Slander (D) Libel 8. An individual’s legal document that names the person authorized to make all healthcare decisions, should they be unable to, is called a:

1. Accepting responsibility to per orm a unction outside the scope o practice

1. Living Will

2. Failure to obtain pertinent in ormation or the radiologist

3. Last Will and Testament

3. Failure to share newly acquired knowledge with peers

(B) 1 and 2 only

(A) 1 only (B) 1 and 2 only (C) 1 and 3 only (D) 1, 2, and 3 4. Which organization has the authority to impose pro essional sanction on a radiographer? (A) ARRT (B) ASRT (C) JRCERT (D) TJC 5. A radiographer who discloses con dential in ormation to unauthorized individuals may be ound liable or:

2. Advance Health Care Directive (A) 1 only (C) 2 and 3 only (D) 1, 2, and 3 9. The legislation that guarantees con dentiality o all patient in ormation is: (A) HSS (B) HIPAA (C) HIPPA (D) MQSA 10. I the patient lacks decision-making capacity, their rights can be exercised on their behal by: 1. Designated surrogate 2. Designated proxy 3. No one

(A) Assault

(A) 1 only

(B) Battery

(B) 2 only

(C) Intimidation

(C) 1 and 2 only

(D) De amation

(D) 3 only

CHAPTER 1 LEGAL AND ETHICAL ASPECTS

Answers and Explanations 1. (B) Radiographers should be amiliar with their Practice Standards published by the American Society o Radiologic Technologists (ASRT). The Standards provide a legal role de nition and identi y Clinical, Quality, and Pro essional Standards o practice—each Standard has its own rationale and identi es general and speci c criteria related to that Standard. The student radiographer can access the individual standards, their rationale, and criteria on the ASRT website. The American Registry o Radiologic Technologists (ARRT) establishes principles o professional conduct to ensure the best services possible to patients entrusted to our care. These principles are detailed in the ARRT two-part Standards of Ethics, which includes the Code o Ethics and the Rules o Ethics. The 10-part Code o Ethics is aspirational; the 22 Rules o Ethics are en orceable and violation can result in pro essional sanction. 2. (C) The 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. Radiography program have Honor Codes in place that must be adhered to by all students. Honor Code in raction can result in suspension or dismissal/expulsion rom the program. 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 ARRT certi cation requirements, candidates or the ARRT examination must answer the question “Have you ever been suspended, dismissed, or expelled rom an educational program that you attended in order to meet ARRT certi cation requirements?” in addition to reading and signing the “Written Consent under FERPA,” allowing the ARRT to obtain speci c parts o their educational records concerning violations to an honor code. I the applicant answers “yes” to that question he/she must include an explanation and documentation o the situation with the completed application or certi cation. I the applicant has any doubts, he/she should contact the ARRT Ethics Requirements Department at (651) 687-0048, ext. 8580. 3. (A) Accepting responsibility to per orm a unction outside the scope o practice is a violation o Ethical Rule #7, which states that it is a violation to “delegate or accept delegation

o a radiologic technology unction or any other prescribed healthcare unction when the delegation or acceptance could reasonably be expected to create an unnecessary danger to a patient’s li e, health, or sa ety. Actual injury to a patient need not be established under this clause.” So, accepting a responsibility outside the scope o practice is a violation o an ARRT rule. However, choices 2 and 3 are in violation o the aspirational Code o Ethics. 4. (A) The ARRT establishes principles o pro essional conduct to ensure the best services possible to patients entrusted to our care. These principles are detailed in the ARRT two-part Standards of Ethics, which includes the Code o Ethics and the Rules o Ethics. The 10-part Code o Ethics is aspirational; the 23 Rules o Ethics are en orceable and violation can result in pro essional sanction. The ARRT Ethics Committee provides peer review o cases (misdemeanor, elony, etc.) to ensure adherence to standards o pro essional behavior and possession o the moral character required to practice in the healthcare pro essions. I the violator’s actions demonstrate that moral character is lacking, that individual can be sanctioned—that is, reprimanded, suspended, revoked, ineligible or certi cation, etc., or other sanctions deemed appropriate by the Ethics Committee. 5. (D) A radiographer who discloses con dential in ormation to unauthorized individuals may be ound guilty o invasion of privacy or defamation. A radiographer whose disclosure o con dential in ormation is in some way detrimental to the patient 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. 6. (B) The AHA identi es 12 important areas in its Patient’s Bill of Rights. These include the right to re use treatment (to the extent allowed by law), the right to con dentiality o records and communication, and the right to continuing care. Other patient rights identi ed are the right to in ormed consent, privacy, respect ul care, access to personal medical records, re usal to participate in research projects, and an explanation o one’s hospital bill. 7. (B) Assault is to threaten harm; battery is to carry out the threat. A patient may eel suf ciently intimidated to claim assault by a radiographer who threatens to repeat a dif cult examination i the patient does not try to cooperate better. A radiographer who per orms an examination on a patient without the patient’s consent or a ter the patient has

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re used the examination may be liable or battery. A charge o battery may also be made against a radiographer who treats a patient roughly or who per orms an examination on the wrong patient. A radiographer who discloses con dential in ormation to unauthorized individuals may be ound liable or invasion of privacy or defamation. A radiographer whose disclosure o con dential in ormation is in some way detrimental to the patient may be accused o de amation. Spoken de amation is slander; written de amation is libel. 8. (B) Patient’s rights can be exercised on the patient’s behal by a designated surrogate or proxy decision maker i the patient lacks decision-making capacity, is legally incompetent, or is a minor. Many people believe that potential legal and ethical issues can be avoided by creating an Advance Health Care 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 Health Care Directive, or Living Will, names the individual 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. 9. (B) 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. The healthcare pro essional generally has access to the computerized system only via personal password, thus helping 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. 10. (C) Patient’s rights can be exercised on the patient’s behal by a designated surrogate or proxy decision maker i the patient lacks decision-making capacity, is legally incompetent, or is a minor. Many people believe that potential legal and ethical issues can be avoided by creating an Advance Health Care 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 Health Care Directive, or Living Will, names the individual 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.

Patient Communication and Safety

2

OBJECTIVES At the conclusion o this chapter, the student will be able to: • Identi y the types o communication and cite examples o each. • Discuss ways in which e ective communication skills meet the needs o various cultural groups. • Discuss techniques to reduce patient anxiety in various age-speci c groups. • Identi y the vital signs and their norms. • Discuss the value o objective and subjective patient in ormation. • Compare trans er methods or wheelchair versus stretcher patient transport. • List rules o body mechanics appropriate or the radiographer.

COMMUNICATIONWITHPATIENTS T e importance o e ective and pro essional patient communication skills cannot be overstressed; 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 proessional appearance/image.

E ective Communication Begins With

• •

Establishing patient identity Establishing trust and rapport 15

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Patient Identif cation

•

Most facilities require checking at least two patient identi ers

E ective communication begins with establishing trust and rapport. T e technologist/student introduces himsel /hersel to the patient and then ollows with veri cation o patient identity. Care must be taken when making the initial patient identi cation. Patient identi cation, and correct matching o 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. I the radiographer calls out a name into a rather ull waiting room, or asks a patient i he is Mr. so-and-so, an anxious patient might readily respond in the a rmative without actually having heard his or her name called. T e radiographer must check the patient’s wristband and ask the patient or a second veri cation, such as his or her birth date. I the patient has no wristband, de nite identi cation must be documented by having the patient state their ull name and date o birth. E ective communication with patients should also begin with a review o relevant patient history, o en including ascertainment o the patient’s current medication(s). T e acquisition o pertinent clinical history rom the patient is one o the most valuable contributions to the diagnostic process. Because the diagnostic radiologist rarely has the opportunity to speak with the patient, this is a crucial responsibility o the radiographer. For instance, to report that your patient indicates most pain at his or her medial malleolus is ar more valuable than simply saying that his or her leg hurts. Review o patient in ormation be ore bringing the patient to the radiographic department also enables the radiographer to have the x-ray room prepared, with all equipment and accessories readily available. However, it is exceedingly important to respect patient privacy and HIPAA (Health Insurance Portability and Accountability Act) regulations. Be certain to interview the patient in a manner/place that your conversation cannot be overheard by individuals not involved with that patient’s examination.

Verbal/Written and Nonverbal Communication

Verbal Communication is Impacted by

• • •

Tone and rate of speech Eye contact Vocabulary

Scenario #1: Consider the nonverbal messages communicated to a patient brought into a disorderly examination room, or by a radiographer’s sloppy, poorly groomed appearance. What about the grim- aced pro essional who hurries the patient along to the radiographic room, gives rapid- re instructions to the patient while searching or missing markers and other accessories, tosses the patient about on the x-ray table, and nally dismisses the patient with a curt “you can go now”? T e disorderly x-ray room and sloppy appearance o the radiographer indicate disrespect or the patient and a negative eeling about onesel and one’s pro ession. T at impression is urther cemented by lack o preparedness, as well as an apathetic and generally uncaring attitude toward the patient. Scenario #2: Consider another patient, greeted by a smiling pro essional who introduces himsel /hersel and brings the patient to a neat and orderly radiographic room, where everything is in readiness or the procedure. T is radiographer explains the procedure, listens to what the patient has to say, and care ully answers the patient’s questions. At the

CHAPTER 2 PATIENT CO MMUNICATIO N AND SAFETY

end o the examination, the patient is escorted back to the waiting area and clear instructions are given or any required postprocedural care. Which scenario provides the patient with a more com ortable, anxietyree examination? Which patient leaves the hospital or clinic environment with a more avorable impression o his or her healthcare experience? Which patient is likely to return to that acility or any additional required diagnostic studies? Which experience would you pre er or yoursel or a loved one? T e volume o the radiographer’s voice and rate o speech are also important actors to consider in e ective communication. T e radiographer should ace the patient and make eye contact during communication. Loud, rapid speech, and/or movement are unpleasant to most people and particularly uncom ortable or the sick patient and/or the elderly. A conscious e ort should be made to use a well-modulated tone and calm demeanor. Patients with even minor hearing loss will greatly bene t when the speaker aces him/her. X-ray examinations may be requested by an appropriately quali ed individual—usually a physician or physician assistant. Written and/or verbal instructions and requests received by the radiographer must be clearly understood. Request orms or radiologic examinations should be care ully reviewed by the radiographer prior to commencement o the examination. I the radiographer has any question about the examination to be per ormed, or receives conf icting/questionable in ormation rom the patient, it is his/her duty to clari y all in ormation and documentation be ore proceeding. Many hospitals and radiology departments have speci c rules about exactly what kind(s) o in ormation is required to be included on requisition orms.

Explanation of Procedure It is imperative that the radiographer takes adequate time to thoroughly explain the procedure or examination 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. T e radiographer must employ good listening skills, that is, looking at the patient and listening care ully without interruption. Patient anxiety can be relieved by explaining procedures and answering questions in a simple, clear, and direct manner, avoiding the use o elaborate medical terminology. E ective communication skills require the use o layman’s terms and an explanation should be given or any technical terms employed. Patients should be clear about what will be expected o them and what they may expect rom the radiographer. Patients o en have questions about other scheduled diagnostic imaging procedures, such as mammography, computed tomography (C ), magnetic resonance (MR) imaging, sonography, or nuclear medicine studies. T ey o en inquire about the length o an examination as well as ask other questions relating to sa ety or contraindications or an

Examples o Nonverbal Communication

• • • • • •

Personal appearance Appearance of work area Facial expression Touch Eye contact Other body language

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examination. T e diagnostic radiographer must be well in ormed and able to e ectively respond to questions relating to all types o examinations. I the radiographer is unsure about how to answer a patient’s concerns, he/she must know where to get the proper in ormation. Patient concerns o en relate to diet restrictions or other preparation that may be required or C or sonography; concerns or contraindications or some examinations such as MR imaging; and positioning techniques such as compression used in mammography. T e radiographer should also be able to help the patient obtain in ormation about these and other services he or she might require, or example, social services, rehabilitation, and spiritual counseling.

Explanation of Aftercare Radiographers must be certain to provide patients with appropriate a ercare instructions (e.g., plenty o f uids ollowing barium examinations). o alleviate the anxiety associated with diagnostic imaging examinations and procedures, patients could be encouraged to repeat explanations or instructions (to the radiographer) to be certain they understand; some have an additional question or two they must ask to clari y their thoughts. T e radiographer’s patience and understanding at these times is greatly appreciated by the anxious patient or relative.

COMMUNICATIONCHALLENGES Cultural and Other

Cultural Groups Include

• • • • • • • •

Religious groups Age groups Racial groups Socioeconomic groups Handicapped groups Gender groups Sexual preference groups Geographic groups

Gaining the patient’s con dence and trust through e ective communication is an essential part o the radiographic examination. Some patients present challenges and will require a greater use o the radiographer’s communication skills—patients who are seriously ill or injured; traumatized patients; patients who have impaired vision, hearing, or speech; in ants and children; non–English-speaking patients; the elderly and in rm; the physically or mentally impaired; alcohol and drug abusers, the amilies o patients—radiographers must adapt their communication skills to meet the needs o all individuals. 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. Misunderstandings between cultures can occur as a result o seemingly innocuous circumstances—such as standing too close while speaking to another, looking directly into someone’s eyes, or the use o certain gestures. Gestures 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 that child’s 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.

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Furthermore, there are signi cant cultural di erences regarding “personal space.” In the United States, people are com ortable speaking about 18 inch apart; in the Middle East, people stand much closer together to speak, while in England people stand urther apart when speaking. 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 the most signi cant barrier to good communication. It is essential that we have an awareness o our own ethnocentrism.

Medical Terminology Although many individuals today are knowledgeable healthcare consumers, we cannot assume that all patients understand the medical terminology or technical jargon o radiologic procedures. Using language that is not comprehensible to patients can make them eel intimidated and cause them unnecessary anxiety. Patient anxiety can be relieved by explaining procedures and answering questions in a simple, clear, and direct manner—avoiding the use o elaborate medical terminology. Let patients know you are there or them—not simply to per orm the x-ray examination, but to help them understand and to be as com ortable as possible.

Techniques to Improve Communication Many patients are anxious about their illness/condition and are un amiliar with the procedure they are about to undergo. Communication di culties can be simply and signi cantly improved through explanation. Since anxious patients require more time to think and to move, a radiographer who takes the time to explain the procedure, explain un amiliar terminology, and answer patient’s questions will be long remembered and appreciated by that patient. Elderly patients, or example, dislike being pushed or hurried about. T ey appreciate the radiographer who is compassionate enough to take the extra ew minutes necessary or com ort. Some elderly patients are easily con used; it is best to address them by their ull name and to keep instructions simple and direct. T e elderly deserve the same courteous, digni ed care as all other patients. Many people today enjoy longer and quite active lives. Consequently, the term elderly is likely to be de ned di erently by di erent people. Many textbooks describe old/elderly as over 80 years o age, but even that varies with the individual. Ageism is discrimination against aged persons. Another special population that should be considered care ully in the imaging department is in ants and children. 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. In ant (birth to one-year) care includes minimizing separation anxiety by keeping in ant and parent(s) together, keeping a amiliar object or two (toy, blanket) with the in ant, and limiting the number o sta present in the x-ray room. Toddlers (1 to 2 years) should be spoken to at eye level; the radiographer should be cheer ul and unhurried. alking to the child cheer ully and having a play ul manner can signi cantly reduce his or her anxiety and help him or her be more cooperative.

Age -Specif c Care

• • • • • • • • •

Infant: birth to one year Toddler: 1–2 years Preschooler: 3–5 years School age: 6–12 years Adolescent: 13–18 years Young adult: 19–45 years Middle adult: 46–64 years Older adult: 65–79 years Elderly: over 80 years

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Preschoolers (3 to 5 years) bene t rom simple explanations o what you will be doing and how they can help you. Be honest with school-age children (6 to 12 years), explain what you will be doing and let them help whenever possible. Adolescents (13 to 18 years) require privacy and modesty. Establish rapport by striking up conversation about hobbies or other interests. Young adults are described as 19 to 45 years. T ese years, early on, is usually a time o gaining greater independence. Later, the demands o career, marriage, and children are o greatest importance. It is a time o beginning to recognize more clearly one’s own vulnerability. T e young adult depends on a calm, competent, pro essional to ease his/her apprehensions. T e middle adult is described as 46 to 64 years and the older adult as 65 to 79 years. As baby boomers age, these groups are increasing in number. During this time common issues that can arise deal with vision, hearing, bone mass, muscle tone, weight gain, and diet restrictions. T ese individuals are o en concerned about loss o autonomy. T e radiographer can help by keeping them involved with their examination and allowing them to make any possible choices. Communication di 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.

Summary • T e healthcare worker has primary responsibility or checking/veri ying patient identity. • Patients must be identi ed by checking their wristbands and requesting a second identi er veri cation such as birth date. • Most healthcare acilities require that examination requests include pertinent diagnostic in ormation, mode o transport, and any in ection control or isolation in ormation. • Verbal communication involves the tone and rate o speech as well as what is being said. It involves personalization and respect. • Nonverbal communication involves acial expression, touch, eye contact, pro essional appearance, orderliness o the radiographic department, and the preparation and e ciency o the radiographer. • T e radiographer must clari y any unclear or contradictory in ormation or documentation be ore proceeding with the examination. • A thorough explanation o procedures reduces the patient’s anxiety, increases cooperation, and results in a better examination.

CHAPTER 2 PATIENT CO MMUNICATIO N AND SAFETY

• T e radiographer must be able to provide accurate af ercare in ormation and ably address patient’s questions about other imaging studies. • Patients should receive explanations in a simple, clear, and direct manner, without the use o elaborate medical terminology. • Communication challenges can arise with many patients; or example, the seriously ill, traumatized; impaired senses; children; non– English-speaking; elderly, in rm; mentally impaired; substance abusers, and patients’ amilies.

EVALUATINGPATIENTCONDITION T e radiographer must assess a patient’s condition be ore bringing the patient to the radiographic department and during the diagnostic examination. A good place to begin is with a review o the patient’s chart. Other use ul in ormation includes the admitting diagnosis and recent nurses’ notes including in ormation regarding the patient’s degree o ambulation, any preparation or the x-ray procedure and how it was tolerated, notes regarding laboratory tests and possible need to save patient urine. As the radiographer obtains a brie pertinent clinical history, he or she also assesses the patient’s condition by observing and listening. o provide sa e and e ective care, the radiographer must be able to assess the severity o a traumatized patient’s injury, the patient’s degree o motor control, and the need or support equipment or radiographic accessories. Can the patient move or be moved rom the stretcher? Can the anatomic part be imaged adequately and with less pain on the stretcher or in the wheelchair? Will the use o sponges and/or sandbags result in a more com ortable, sa er, and better-imaged examination?

Physical Signs When the patient is rst approached, 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 o en re erred to as objective signs. It is important to notice the color, temperature, and moistness o the patient’s skin. Paleness requently indicates weakness; the diaphoretic patient has pale, cool skin. T e ebrile patient is usually 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. It is important that the radiographer be aware o patient gross and ne motor control in order to avoid patient injury. Gross/general motor control re ers to basic body movement and locomotion, such as walking or waving one’s arm. Fine motor control involves the coordination o bones, muscles, and nerves to produce smaller and more precise movements/tasks such as zipping a zipper or grasping and writing with a pencil. Conditions o the brain, spinal cord, nerves, muscles, and bony articulations (such as in Parkinson’s disease) impair ne motor control.

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Subjective signs are those perceived by the patient—how they eel, what is the level o their pain, etc. Subjective in ormation can be just as valuable as objective in ormation, and the radiographers listening skills can have a great deal to do with the patient’s lasting impression o their healthcare experience.

Vital Signs

Vital Signs

• • • •

Body temperature Pulse rate Respiratory rate Arterial blood pressure

Normal Body Temperatures Adult Oral Rectal Axillary Infant to age 4 years Child aged 5–13 years

98.6°F 99.1°F–99.6°F 97.6°F–98.1°F 97.9°F–100.4°F (rectal) 97.8°F–98.6°F

Common Pulse Points Artery Radial Carotid Temporal Femoral Popliteal

Location Wrist; at base of thumb Neck; just lateral to midline In front of upper ear Inguinal region; groin Posterior knee

Vital signs can provide crucial in ormation about an individual state o health. T e radiographer employed in an o ce environment o en nds vital signs measurement part o their routine duties. I a medical emergency arises in the hospital radiology area, the radiographer may be required to assist by obtaining the patient’s vital signs. Although checking vital signs is not a routine unction, the radiographer should be procient and con dent i and when the need arises. Practicing the skills associated with taking vital signs during “slow” periods can bene t the patient during an emergency situation, and those on whom you practice will learn their baseline signs—which provide valuable in ormation or everyone. Obtaining vital signs involves the measurement o body temperature, pulse rate, respiratory rate, and arterial blood pressure. Body temperature varies with the time o day and site o measurement. It can be measured via a thermometer in the mouth, rectum, axilla, bladder, heart chamber, or external auditory canal. T e pulse rate should be counted or 30 seconds and multiplied by two. Attention should be given to pulse regularity and volume. Increased body temperature, or ever, usually signi es in ection. Symptoms o ever include general malaise, increased pulse and respiratory rates, f ushed skin that is hot and dry to the touch, and occasional chills. Patients who experience very high, prolonged evers can su er irreparable brain damage. Normal body temperature varies rom person to person depending on several actors, including age. A normal adult body temperature taken orally is 98.6°F (37°C). Rectal temperature is generally 0.5°F to 1.0°F higher, whereas axillary temperature is usually 0.5°F to 1.0°F lower. A variation o 0.5°F to 1.0°F is generally considered within normal limits. Body temperature is usually lowest in the early morning and highest at night. In ants and children have a wider range o body temperature (rectal: 97.9°F–100.4°F) than do adults; the elderly have lower body temperatures than do others. In ants and children up to 4 years have normal (tympanic) body temperatures o between 96.4°F and 100.4°F. Children aged 5 to 13 years have a normal body temperature range o 97.8°F to 98.6°F. Body areas having super cial arteries are best suited or determination o a patient’s pulse rate. T e ve most readily palpated pulse points are the radial, carotid, temporal, emoral, and popliteal pulse. O these, the radial pulse is the most requently used. T e apical pulse, at the apex o the heart, may be readily evaluated with the use o a stethoscope. Pulse rate depends on the person’s age, sex, body exertion and position, and general state o health. T e very young and the very old have higher rates. Pulse rate increases in the standing position, a er exertion, and with certain conditions, such as ever, organic heart disease, shock, and alcohol and drug use. Certain variations in the regularity and

CHAPTER 2 PATIENT CO MMUNICATIO N AND SAFETY

strength o the pulse are characteristic o various maladies. Pulse rates vary between men and women and among adults, children, and in ants; athletes o en have lower pulse rates. T e act o respiration serves to deliver oxygen to all the body cells and rid the body o carbon dioxide. T e radiographer must be able to recognize abnormalities or changes in patient respiration. T e general term used to describe di cult breathing is dyspnea. More speci c terms used to describe abnormal respirations include uneven, spasmodic, strident (shrill, grating sound), stertorous (labored, e.g., snoring), tachypnea (abnormally rapid breathing), orthopnea (di culty breathing while recumbent), and oligopnea (abnormally shallow, slow). A patient’s respirations should be counted a er counting the pulse rate, while still holding the patient’s wrist. Respiratory action may become more deliberate and less natural in the patient who is aware that his or her respirations are being counted. Respirations should be counted or at least 30 seconds; 15-second counting multiplied by our can result in a airly large error. T e normal adult respiratory rate is 12 to 18 breaths/min. T e respiratory rate o young children is somewhat higher, up to 30 breaths/min. Although the radiographer is counting respirations, he or she should also be assessing the respiratory pattern (even, uneven) and depth (normal, shallow, deep). Blood encounters a degree o resistance as it travels through the peripheral vascular system; thus, a certain amount o pressure exists within the walls o the vessels. It is measured and read in millimeters o mercury (mm Hg). Blood pressure among individuals varies with age, sex, atigue, mental or physical stress, disease, and trauma. T e blood pressure within vessels is highest during ventricular systole (contraction) and lowest during diastole (relaxation). Blood pressure measurements are recorded with the systolic pressure on top and the diastolic pressure on the bottom, as in 100/80 (read “one hundred over eighty”). Normal adult systolic pressure ranges between 100 and 140 mm Hg, whereas the normal diastolic range is between 60 and 90 mm Hg. Prehypertension is present when blood pressure measurements are between 120 and 140 mm Hg systolic and/or between 80 and 90 mm Hg diastolic. Blood pressure consistently above 140/90 mm Hg is considered hypertension. Le undiagnosed and untreated, hypertension can lead to renal, cardiac, or brain damage. Hypotension is characterized by a systolic pressure o less than 90 mm Hg. Hypotension is seen in individuals with a decreased blood volume as a result o hemorrhage, in ection, ever, and anemia. Orthostatic hypotension occurs in some individuals when they rise quickly rom a recumbent position. Blood pressure is measured using a sphygmomanometer and stethoscope. T e patient may be recumbent or seated with the arm supported. T e cu o the sphygmomanometer is wrapped snugly around the arm, with its lower edge just above the antecubital ossa. With the stethoscope earpieces in place, the brachial artery pulse is palpated in the antecubital ossa and the bell (diaphragm) o the stethoscope is placed over the brachial artery. T e valve on the bulb pump is closed and the cu inf ated enough to collapse the brachial artery (approximately 180 mm Hg). T e valve is then opened very slowly. T e rst sound heard is the systolic pressure; as the valve pressure is slowly released, the sound

Normal (resting) Pulse Rates (beats/min) Men Women Children Infants

68–75 72–80 70–100 100–160

Blood Pressure Is A ected by

• • •

Cardiac output Blood volume Vascular resistance

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Blood Pressure

•

Measured using a sphygmomanometer and stethoscope

•

Cu in ation su cient to collapse the brachial artery

•

First sound heard is systolic pressure

becomes louder and then suddenly gets so er—this is the diastolic pressure. A er the blood pressure measurements are recorded, the stethoscope earpieces and bell should be cleaned.

Summary • Radiologic examinations can be requested by a physician or physician assistant. • T e radiographer should examine the requisition care ully be ore bringing the patient to the radiographic department. • Patient condition may be assessed through chart in ormation, observation, questioning, and vital signs. • A patient’s vital signs are temperature, pulse and respiration rates, and blood pressure. • A normal adult oral body temperature is 98.6°F, axillary temperatures are 0.5° to 1° lower, and rectal temperatures are 0.5° to 1° higher. • T e arterial pulse points include radial, carotid, temporal, emoral, and popliteal. • T e normal adult pulse rate is 70 to 80 beats/min; in ant and children pulse rates are higher. • T e normal adult respiratory rate is 12 to 18 breaths/min, with children’s respirations being higher (up to 30 breaths/min). • Dyspnea re ers to di culty breathing; other terms are used to describe speci c respiratory abnormalities. Blood pressure is measured using a sphygmomanometer and stethoscope. • T e average normal adult systolic blood pressure is less than 120 mm Hg, whereas average normal adult diastolic blood pressure is less than 80 mm Hg; blood pressure varies with a person’s age, sex, atigue, mental or physical stress level, disease, and with trauma. • Systolic pressure (contraction) is the top number, whereas diastolic pressure (relaxation) is the bottom number.

PHYSICALASSISTANCEANDTRANSFER Body Mechanics Radiographers work with many patients whose capacities or ambulation vary greatly. Outpatients are usually ambulatory, that is, able to walk and not con ned to bed. Ambulatory inpatients generally travel by wheelchair, whereas patients con ned to bed must travel by stretcher. It is essential or the radiographer to use proper technique and body mechanics when trans erring patients, or the sa ety o the patient and the radiographer. Not all patients need, or want, well-intentioned assistance. Many preer to manage on their own. T e radiographer should recognize this, but be ever alert and watch ul should the patient need assistance. Other patients nd it reassuring and eel an added sense o security with an attentive radiographer. T e pro essional radiographer develops a sense o awareness o each patient’s needs and concerns.

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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 inch 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 di cult to maintain. Even the ambulatory outpatient might be somewhat unsteady, so a ready, supporting hand at the elbow can be very help ul. T e radiographer should keep a watch ul eye on the patient and assist him or her as needed.

Patient Transfer Be ore helping a patient into or out o a wheelchair, it must rst be positioned 45 degrees to the bed/x-ray table and locked. T e ootrests must be moved aside to avoid tripping over them or tilting the wheelchair orward. Once the patient is seated, the ootrests should be lowered into place or the patient’s com ort. When the patient is trans erred rom the wheelchair to the x-ray table, the patient’s stronger side should approach the x-ray table rst, while the radiographer assists his or her weaker side. I the x-ray tables possess controls to adjust the height, this can greatly acilitate patient trans er and make the process sa er or the patient as well as or the radiographer. It is essential that someone should be responsible or keeping any intravenous (IV) tubing, catheters, oxygen lines, or other equipment ree rom entanglement during wheelchair and/or stretcher trans ers. Once the trans er is complete, the patient may be adjusted into the Fowler position (head higher than eet) or com ort or ease o breathing. T e radiographer must be certain that sa ety belts and/or side rails are appropriately used or any patient on a stretcher.

Transfer Conditions Requiring Special Attention It is the healthcare practitioner’s responsibility to ensure patient sa ety and com ort while the patient is in his or her care. T e radiographer should make a mental note o what the patient has in his or her possession when he or she enters the department, such as glasses or a purse. Patient belongings should be properly secured according to institution or department policy. T e radiographer must be certain that the radiographic department is hazard ree, that all equipment and accessories are used properly and sa ely, and that the patient is as com ortable as possible. When moving to or rom the wheelchair or stretcher, patients should always be assisted or, at least, given care ul attention. T e x-ray tube must be moved away rom the x-ray table, the x-ray table lowered or a ootstool in place to assist the patient rom the table, and the radiographer must be there to guide or assist the patient sa ely to the correct dressing room. I an injured patient requires assistance with dressing and undressing, it is important to remember that clothing should be removed rom the uninjured side rst and placed on the injured side rst.

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Other Rules o Good Body Mechanics 1. When carrying a heavy object, hold it close to the body 2. The back should be kept straight; avoid twisting 3. When lifting an object, bend the knees and use leg and abdominal muscles to lift (rather than the back muscles) 4. Whenever possible, push or roll heavy objects (rather than lifting or pulling)

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Sa ety/Com ort Guidelines

• • • • •

Belongings secure Hazard-free environment to avoid unnecessary/painful movement Equipment used properly Remove clothing rst from uninjured side Place clothing rst on the injured side

Special consideration must be given to each patient according to his or her condition. Elderly and very thin patients, and those who will be required to lie on the x-ray table or a lengthy period o time, bene t greatly rom a oam pad between themselves and the x-ray table. Lumbar strain is relieved by a pillow or positioning sponge placed under the knees. An extra pillow or the head or cushioning under the heels or ischial tuberosities can make a big di erence in patient care. Special care and attention should be given to the skin o the elderly, as it bruises and bleeds easily. Patients who are sedated, senile, in shock, or under the inf uence o alcohol or drugs must never be le unattended. Patients who arrive in the radiology department with restraints in place must never be le alone on the x-ray table, since they are usually active, disoriented, and occasionally, combative. Indeed, many radiology departments have rules stating that no patient may ever be le unattended in the radiographic department. Patients with IV in usions in place require added attention. T e IV standard/bag should be 18 to 24 inch above the level o the vein. T e in usion site should be checked periodically or any signs o tissue in ltration. Swelling around the needle site generally indicates that the needle or catheter is no longer in the vein and that the medication is in ltrating the surrounding tissues. T e radiographer should turn o the IV and noti y the physician or nurse. Di culty in communication can be encountered with a patient having a tracheostomy in place. T ese individuals are o en anxious because they cannot communicate verbally and they are ear ul o choking because they cannot remove the secretions that accumulate in their throats. T ey require care ul attention. T e nurse should be available to suction secretions i the patient starts to breathe noisily or with di culty. T e radiographer can relieve much patient anxiety by care ul explanation o the examination. T e patient can be provided with a pencil and pad to communicate any questions or concerns. Just as healthcare practitioners provide or patient sa ety and comort, they must ensure their own sa ety by practicing good body mechanics, in ection control, and standard precautions. Should an accident ever occur and a patient or healthcare practitioner be injured, no matter how small or insigni cant the injury seems, it must be reported to the supervisor and an incident report completed. T e risk management team, or similar group, requires all such in ormation or legal documentation and as a means o identi ying and resolving potential hazards.

Summary • Modes o patient transportation include ambulation, wheelchair, and stretcher. • Patient and radiographer sa ety requires the use o proper and sa e body mechanics. • Wheelchairs and stretchers must be locked and wheelchair ootrests positioned out o the way prior to patient trans er.

CHAPTER 2 PATIENT CO MMUNICATIO N AND SAFETY

• One person should be responsible or the sa e transport o IV lines, catheters, and other tubes. • Patient trans er between the radiographic table and the stretcher should involve pulling, not pushing; a smooth plastic board o en helps. • T e knees should be bent when li ing heavy objects; leg and abdominal muscles are used instead o back muscles. • Heavy objects should be carried close to the body; the back should be kept straight and twisting motions should be avoided. • Heavy objects (e.g., mobile x-ray unit) should be pushed or rolled (instead o pulled or li ed) whenever possible. • Patient belongings should be properly secured according to policy while the patient is in the radiographer’s care. • T e radiographer must be alert or patient sa ety and com ort at all times; patients should not be le unattended in the radiographic department. • Should an accident occur involving the patient and/or radiographer, accurate documentation should be completed regardless o how minor the incident.

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COMPREHENSION CHECK Congratulations! You have completed your review of this chapter. If you are able to answer the following group of comprehensive questions, you can feel con dent that you have mastered this section. You are then ready to go on to “Registry-type” questions that follow. For greatest success, do not go to the multiple-choice questions without rst completing the short-answer questions below. 1. Explain the importance of reviewing the examination request and other patient information before bringing the patient to the radiographic department (p. 16). 2. Discuss the best way(s) to ensure correct identi cation of a patient (p. 16). 3. Explain the importance of obtaining patient history (p. 16). 4. Discuss the importance of explaining the procedure to the patient (p. 17). 5. Discuss ve ways through which the radiographer communicates verbal messages to the patient (p. 16, 17). 6. Discuss ve ways through which the radiographer communicates nonverbal messages to the patient (p. 16, 17). 7. Discuss some qualities of verbal communication likely to evoke a positive response from the patient; qualities likely to evoke a negative response (p. 16, 17). 8. Explain the value of making as many preparations as possible before bringing the patient to the radiographic department (p. 16). 9. Discuss ve types of patients who might require special communication e orts on the part of the radiographer (p. 19, 20). 10. List ve bene ts of e ective communication skills (p. 16, 17). 11. Discuss potential sources/causes of cultural misunderstanding (p. 18–20). 12. Discuss the importance of being alert to the initial patient condition and any subsequent changes in condition (p. 21).

13. Identify and describe the two types of motor control (p. 21). 14. Identify the following with respect to body temperature (p. 21, 22). A. Normal adult, infant, and child temperature B. The signi cance of fever, that is, what it usually indicates C. Symptoms usually associated with fever D. Di erence among oral, rectal, and axillary temperatures 15. Identify the following with respect to pulse rate (p. 22, 23). A. The normal, average adult pulse rate for men and women B. Normal and abnormal conditions under which pulse rate will vary/change C. The usual site of pulse determination; other possible sites/any special equipment needed 16. Identify the following with respect to respiration (p. 23). A. Its function B. The ideal time to determine patient respiration rate; why? C. The normal, average adult respiratory rate 17. Identify the following with respect to blood pressure (p. 23, 24). A. Equipments necessary B. Position of patient C. Position of cu and bell D. First and second sounds heard E. Maximum norms for systolic and diastolic pressures F. Prehypertensive and hypertensive pressures 18. Discuss three modes of patient transport (p. 24, 25). 19. Discuss some special needs that a tracheostomy patient might have (p. 26).

CHAPTER 2 PATIENT CO MMUNICATIO N AND SAFETY

20. Identify, with respect to body mechanics and patient transfer (p. 25, 26). A. Position of radiographer’s feet (as base of support) B. The body’s center of gravity (vis-à-vis stability) and when moving heavy objects: push versus pull; use of knees, legs, and back; proximity of object to body C. Position of chair, footrests, and locks during wheelchair transfers D. Position of locks, use of drawsheet and plastic mover, push versus pull in stretcher transfer E. Care of IV lines, catheters, O2, safety belts, and side rails

21. Identify the manner in which patients should be directed onto, and removed from, the x-ray table (p. 25, 26). 22. Explain how clothing should be removed from a patient with unilateral injury (p. 26). 23. Identify techniques used to reduce discomfort of elderly and/or thin patients recumbent on the radiographic table (p. 25). 24. Discuss the types of patients likely to be at greater risk left unattended on the radiographic table (p. 26).

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CHAPTER REVIEW QUESTIONS 1. An individual’s blood pressure can vary with:

6. A patient who is diaphoretic has:

1. Level of fatigue

(A) Pale, cool, clammy skin

2. Mental stress

(B) Hot, dry skin

3. Age

(C) Dilated pupils

(A) 1 only

(D) Warm, moist skin

(B) 2 only (C) 1 and 2 only (D) 1 and 3 only 2. When an injured patient requires assistance with dressing or undressing, the radiographer must remember to: 1. Place clothing on the injured side rst 2. Remove clothing from the injured side rst

7. A pulse can be detected only by the use of a stethoscope in which of the following locations? (A) Wrist (B) Neck (C) Groin (D) Apex of the heart 8. Which of the following communicate(s) messages to the patient?

3. Always start with the injured side

1. Facial expression

(A) 1 only

2. Eye contact

(B) 1 and 2 only

3. Personal appearance

(C) 3 only

(A) 1 only

(D) 1, 2, and 3

(B) 1 and 2 only

3. Instruments needed to assess vital signs include: 1. Tongue blade 2. Watch with a second hand 3. Thermometer

(C) 3 only (D) 1, 2, and 3 9. What number of breaths per minute represents the average rate of respiration for a normal adult?

(A) 1 only

(A) 8 to 15

(B) 1 and 2 only

(B) 10 to 20

(C) 2 and 3 only

(C) 30 to 60

(D) 1, 2, and 3

(D) 60 to 90

4. The normal adult body temperature, taken orally, is: (A) Usually lower than axillary temperature (B) Usually higher than rectal temperature (C) The same as axillary temperature (D) Usually lower than rectal temperature 5. The period of contraction of the heart chambers is termed: (A) Systole (B) Diastole (C) Hypertension (D) Dyspnea

10. To reduce the back strain associated with transferring patients from stretcher to x-ray table, you should: (A) Pull the patient (B) Push the patient (C) Hold the patient away from your body and lift (D) Bend at the waist and pull

CHAPTER 2 PATIENT CO MMUNICATIO N AND SAFETY

Answers and Explanations 1. (D) Blood pressure among individuals varies with age, sex, fatigue, mental or physical stress, disease, and trauma. The blood pressure within vessels is highest during ventricular contraction/systole and lowest during ventricular relaxation/diastole. Blood pressure measurements are recorded with the systolic pressure on top and the diastolic pressure on the bottom. Normal adult systolic pressure ranges between 100 and 140 mm Hg, whereas the normal diastolic range is between 60 and 90 mm Hg. Prehypertension is present when blood pressure measurements are between 120 and 140 mm Hg systolic and/or between 80 and 90 mm Hg diastolic. Blood pressure consistently above 140/90 mm Hg is considered hypertension. Left undiagnosed and untreated, hypertension can lead to renal, cardiac, or brain damage. Hypotension is characterized by a systolic pressure of less than 90 mm Hg. Hypotension is seen in individuals with a decreased blood volume as a result of hemorrhage, infection, fever, and anemia. 2. (A) Special consideration must be given to each patient according to his or her condition. Should an injured patient require assistance with dressing and undressing, it is important to remember that clothing should be removed from the uninjured side rst and placed on the injured side rst. Elderly and very thin patients, and those who will be required to lie on the x-ray table for a lengthy period of time, bene t greatly from a foam pad placed under them—that is between them and the x-ray table. 3. (C) Obtaining vital signs involves the measurement of body temperature, pulse rate, respiratory rate, and arterial blood pressure. A thermometer is used to take the patient’s temperature. A watch with a second hand is required to time the patient’s pulse rate and respirations. To measure blood pressure, a sphygmomanometer and stethoscope are required. A tongue blade is used to depress the tongue for inspection of the throat and is not part of vital sign assessment. 4. (D) Normal body temperature varies from person to person depending on several factors, including age. Normal adult body temperature taken orally is 98.6°F (37°C). Rectal temperature is generally 0.5° to 1.0° higher, whereas axillary temperature is usually 0.5° to 1.0° lower. Variation of 0.5° to 1.0° is generally considered within normal limits. Body temperature is usually lowest in the early morning and highest at night. Infants and children up to 4 years have normal rectal body temperatures of between

97.4° and 100.4°F. Children aged 5 to 13 years have a normal range of 97.8° to 98.6°F. Obtaining vital signs involves the measurement of body temperature, pulse rate, respiratory rate, and arterial blood pressure. Increased body temperature, or fever, usually signi es infection. Symptoms of fever include general malaise, increased pulse and respiratory rates, ushed skin that is hot and dry to the touch, and occasional chills. Very high, prolonged fevers can cause irreparable brain damage. 5. (A) Blood pressure within vessels is highest during ventricular systole (contraction) and lowest during diastole (relaxation). Blood pressure measurements are recorded with the systolic pressure on top and the diastolic pressure on the bottom, as in 100/75 (read “one hundred over seventy- ve”). Normal adult systolic pressure ranges between 100 and 140 mm Hg, whereas the normal diastolic range is between 60 and 90 mm Hg. Prehypertension is present when blood pressure measurements are between 120 and 140 mm Hg systolic and/or between 80 and 90 mm Hg diastolic. Blood pressure consistently above 140/90 mm Hg is considered hypertension. Left undiagnosed and untreated, hypertension can lead to renal, cardiac, or brain damage. Hypotension is characterized by a systolic pressure of less than 90 mm Hg. Hypotension is seen in individuals with a decreased blood volume as a result of hemorrhage, infection, fever, and anemia. Orthostatic hypotension occurs in some individuals when they rise quickly from a recumbent position. Dyspnea is the medical term used to describe di culty in breathing. 6. (A) The radiographer must be alert to the patient’s appearance and condition, and any subsequent changes in them. Notice the color, temperature, and moistness of the patient’s skin: paleness frequently indicates weakness; the diaphoretic patient has pale, cool skin; fever is frequently accompanied by hot, dry skin; “sweaty” palms may indicate anxiety, a patient who becomes cyanotic (bluish lips, mucous membranes, nail beds) needs oxygen and requires immediate medical attention. 7. (D) Body areas having super cial arteries are best suited for determination of a patient’s pulse rate. The ve most readily palpated pulse points are the radial, carotid, temporal, femoral, and popliteal pulse. Of these, the radial pulse is the most frequently used. The apical pulse, at the apex of the heart, may be readily evaluated with the use of a stethoscope.

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8. (D) The interaction between a patient and a radiographer generally leaves a lasting impression on the patient’s healthcare experience. Communication may be verbal or nonverbal. Verbal communication involves tone and rate of speech as well as what is being said. It involves personalization and respect. Nonverbal communication involves facial expression, professional appearance, orderliness of radiographic department, and preparation and e ciency of the radiographer. 9. (B) A patient’s respirations should be counted after counting the pulse rate, while still holding the patient’s wrist. Respiratory action may become more deliberate, or less natural, in the patient who is aware that his or her res-

pirations are being counted. The normal respiratory rate is 12 to 18 breaths/min. The respiratory rate of young children is somewhat higher, up to 30 breaths/min. Although the radiographer is counting respirations, he or she should be assessing the respiratory pattern (even, uneven) and depth (normal, shallow, deep) as well. 10. (A) When transferring a patient from the stretcher to the x-ray table, several rules apply that will help reduce back strain. Pull, do not push the patient; pushing increases friction and makes the transfer more di cult. Use the biceps muscles for pulling; do not bend at the waist and pull, as this motion increases back strain.

Infection Control

3

OBJECTIVES At the conclusion o this chapter, the student will be able to: • De ne in ection prevention and control terminology. • Discuss the role o personal hygiene in preventing the spread o in ection. • Explain the cycle involved in transmitting in ectious disease. • Identi y the three main modes o in ection transmission and their transmission-based precautions. • Discuss the radiographers approach to dealing with protective isolation/precautions.

TERMINOLOGYANDBASICCONCEPTS Microorganisms Living organisms too small to be seen with the naked eye are re erred to as microorganisms. Most microorganisms do not produce in ection or disease, many reside harmlessly, and many are actually bene cial or our good health, or example, bacteria, protozoa, and ungi ound on/in particular body areas. Speci c permanent ora are ound, or example, in the mouth, upper respiratory tract, and intestines; many o these microorganisms inhibit the growth o pathogens in their natural sites, but can cause in ection i introduced into a site where they do not normally reside, or when introduced into an immunocompromised host. Pathogenic microorganisms are capable o causing in ection or disease by destroying cells or tissues, or secreting toxins. Pathogenic microorganisms can be transmitted rom one host to another. Since hospitals are places that treat and care or in ection and disease, it stands to reason that healthcare practitioners must be particularly vigilant against transmission o pathogenic microorganisms.

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Medical and Surgical Asepsis Antisepsis is a practice that retards the growth o pathogenic microorganisms. Medical asepsis re ers to the destruction o pathogenic microorganisms (bacteria) through the process o disin ection. Examples o disin ectants are hydrogen peroxide, chlorine, iodine, boric acid, and ormaldehyde. Surgical asepsis (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.

Hand Hygiene Ignaz Semmelweis was a Hungarian physician re erred to as the “Father o In ection Control” and as the “Saviour o Mothers”. While working in a Vienna maternity clinic in 1847, Dr. Semmelweis began encouraging interns to cleanse their hands. T e atal puerperal ever (“childbed ever”) incidence was immediately reduced rom 5–30% to 1–2%. However, Semmelweis’ ideas were ridiculed and he was dismissed rom the hospital. oday, we know that the most important precaution in the practice o aseptic technique is proper handwashing. T e radiographer’s hands should be thoroughly washed with soap and warm running water or at least 20 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 may 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; and some o these products are used in handwashing substances. Alcohol-based hand sanitizers have been recommended as an alternative to handwashing with soap and water, except when there is visible soiling or a er caring or a patient with Clostridium di cile (C. di cile) in ection.

Personal Care Uni orms are recommended because clothing worn in patient areas should not be worn elsewhere. Because clothing becomes contaminated in the patient area, a clean uni orm should be worn daily. Microorganisms can nd sa e harbor in jewelry, especially in rings with stones and other crevices; many acilities do not permit healthcare workers to wear arti cial nails, or they can harbor ungi and microbes. T e only jewelry a healthcare practitioner should wear is a wristwatch and simple wedding band. Many microorganisms can remain in ectious while awaiting transmission to another host. Sterile technique is employed during invasive procedures, such as biopsies, and or the administration o contrast media via the intravenous (e.g., C studies) and intrathecal (e.g., myelography) routes. When radiography is required in the surgical suite, every precaution must be made to maintain the surgical asepsis required in surgical

CHAPTER 3 INFECTIO N CO NTRO L

procedures. T is requires proper dress, cleanliness o equipment, and restricted access to certain areas. One example o a restricted area is the “sterile corridor,” the area between the draped patient and the instrument table. Only the surgeon and the instrument nurse occupy this area.

CYCLEOFINFECTION Pathogens Pathogens are causative agents—microorganisms capable o producing disease. Pathogens termed opportunistic are usually harmless, but can become harm ul i introduced into a part o the body where they do not normally reside, or when introduced into an immunocompromised host. Bloodborne pathogens reside in blood and can be transmitted to an individual exposed to the blood or body uids o the exposed individual. Common bloodborne pathogens include hepatitis C virus (HCV), hepatitis B virus (HBV), and human immunode ciency virus (HIV). T e prevention and control o in ection must be a hospital-wide e ort; each department is required to have its own in ection prevention and control protocol, designed according to the risks unique to the services provided. Because radiography o en involves exposure to sickness and disease, the radiographer must be aware o , and conscientiously practice e ective prevention and control measures.

Reservoir of Infection T e reservoir (source) o in ection is any environment where these pathogens can survive and reproduce, and ultimately pose a risk o transmission to a susceptible host. T is environment must a ord an appropriate temperature, moisture, and nutrients—all conditions ound in the human body. Examples o reservoirs o in ection include a patient with active tuberculosis, a visitor with an upper respiratory in ection, or a healthcare pro essional with conjunctivitis. Some people, called “carriers,” can appear healthy yet harbor in ectious microorganisms. Carriers may unwittingly in ect a susceptible host (patient or coworker). Probably the most amous example o an unwitting carrier was Mary Mallon (“ yphoid Mary”), a healthy Irish immigrant whose employment as a cook was traced back to 1900. It was ound that typhoid outbreaks had ollowed Mallon’s employment rom job to job. From 1900 to 1907, Mallon worked at seven places o employment in which 22 people had become ill with typhoid ever shortly a er Mallon came to work or them. Once traced, Mallon did not understand how a healthy person could possibly spread disease. But Mallon was tried in court, subsequently ran rom health o cials, was recaptured, and orced to live in relative seclusion on an island o New York. Mary Mallon was the rst healthy carrier o typhoid ever in the United States. An example o today’s healthy carriers includes asymptomatic carriers o HIV. Although we might think o the human body as the typical reservoir or in ection, any environment that can provide appropriate temperature (warm), moisture (damp), and lack o cleanliness will provide welcome accommodations or pathogenic microorganisms. Animals, arthropods, plants, and soil are all potential reservoirs o in ection.

Factors in Infection Transmission/ Cycle of Infection 1. An in ectious organism/pathogen 2. A reservoir o in ection and environment or pathogen to live and multiply 3. A portal o exit rom the reservoir 4. A means o transmission 5. A susceptible host 6. A portal o entry into the susceptible new host

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Portal of Exit A portal o exit rom the reservoir can be any pathway by which pathogens are able to leave the reservoir. Examples o portals o exit include urine, eces, blood, respiratory droplets, and contaminated solutions.

Susceptible Host T e most susceptible hosts include the sick, in rmed, immunocompromised, very young, poorly nourished, weak, or atigued—all who have a diminished natural resistance to in ection. Healthcare-associated in ections (HAIs), also re erred to as nosocomial in ections, are in ections acquired by patients (susceptible hosts) while they are in the hospital, unrelated to the condition or which the patients were hospitalized. Hospital personnel can also be susceptible hosts. T e most important precaution is proper hand hygiene. Hand lotions may be used; broken skin permits the entry o microorganisms. Disin ectants, antiseptics, and germicides are substances used to kill pathogenic bacteria and, as stated above, are requently used in hand hygiene substances. Alcohol-based hand sanitizers have been recommended as an alternative to handwashing with soap and water, and may be used as previously described. Uni orms worn in patient areas should not be worn elsewhere; a clean uni orm should be worn daily, and minimal jewelry worn. Microorganisms can remain in ectious while awaiting transmission to another host.

Portal of Entry Modes of Transmission

• • •

Droplet Airborne Contact:

• Direct • Indirect (e.g.,

omite)

Other sources o in ection:

• •

Vector Vehicle

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 the mother and the etus.

Modes of Transmission In ectious microorganisms can be transmitted rom patients to other patients or to healthcare workers, and rom healthcare workers to patients. T ere are three main modes o transmission: droplet, airborne, and contact. Pathogenic microorganisms expelled rom the respiratory tract through the mouth or nose can be carried as evaporated droplets through the air or on airborne dust particles and settle on clothing, utensils, or ood. Patients with respiratory tract in ections/disease who are 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—that is, transmission via indirect contact. T e Centers or Disease Control and Prevention (CDC) identi es other sources o in ection. A vector is an insect or animal carrier o in ectious organisms, such as a rabid animal, a mosquito that carries malaria, or a

CHAPTER 3 INFECTIO N CO NTRO L

tick that carries Lyme disease. Vehicle transmission includes anything that transmits in ectious microorganisms; examples o vehicles include contaminated blood, water, ood, and drugs. Direct contact involves touch. T e courteous act o handshaking is a simple way o transmitting in ection rom one individual to another. Diseases transmitted by direct contact include skin in ections such as boils, multi-drug resistant organisms (MDROs) and sexually transmitted diseases such as syphilis and acquired immunode ciency syndrome (AIDS).

Summary • Most microorganisms do not produce in ection or disease; many are harmless and many are bene cial. • Pathogenic microorganisms can cause in ection/disease; pathogenic microorganisms can be transmitted rom one host to another. • Many microorganisms can remain in ectious while awaiting transmission to another host. • Antiseptics retard the growth o bacteria. • Medical asepsis re ers to the destruction o bacteria through the use o disin ectants/antiseptics. • Surgical asepsis re ers to the destruction o all microorganisms and their spores through sterilization. • T e practice o medical asepsis is required at all times, whereas surgical asepsis is required or invasive procedures. • T e single most important component o medical asepsis is proper and timely hand hygiene. • A clean uni orm must be worn daily; uni orms become contaminated and should not be worn elsewhere; pathogenic microorganisms thrive in jewelry crevices and chipped nail polish. • T e six actors in the cycle o in ection are the in ectious organism, the reservoir o in ection, the portal o exit, the susceptible host, the means o transmission, and the portal o entry. • Modes o transmission o in ectious microorganisms are droplet, airborne, and contact (direct and indirect). • Disin ectants (germicides) are used in handwashing liquids to kill microorganisms.

STANDARDPRECAUTIONS Infection Prevention and Control Basic Guidelines T e CDC and the Hospital In ection Control Practices Advisory Committee (HICPAC) have revised and simpli ed in ection control guidelines or hospitals and other healthcare acilities. T e various types o isolation techniques, disease-speci c precautions, and varied terminology have been reviewed, revised, and updated. All these considerations are now incorporated into standard precautions and transmission-based precautions.

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Guidelines for Standard Precautions The radiographer is now legally, as well as ethically, responsible or strict adherence to standard precaution principles identi ed in the ollowing guidelines:

•

Avoid cross-contamination o soiled (with bodily luids) patient care linens/equipment.

•

Clean reusable equipment properly be ore using on another patient; properly discard single-use items.

•

Clean and disin ect environmental sur aces on a routine basis.

•

Patients who can contaminate the environment should be placed in private rooms.

•

Blood and body uid spills should be care ully cleaned and disin ected using a solution o 1 part bleach to 10 parts water.

•

Used needles must not be separated rom the syringe or resheathed, and must be placed in designed puncture-proo containers.

•

Prescribed procedures must be ollowed and su cient care and attention given to risky tasks to avoid needle sticks and other skin penetrations rom cutting instruments (“sharps”).

•

Emergency cardiopulmonary resuscitation (CPR) equipment must include resuscitation bags and mouthpieces.

Regarding use o PPE(Personal Protective Equipment):

•

Shielding or the ace and eyes must be in place whenever the possibility o blood or body luid splashes may occur near the ace.

•

Plastic aprons must be worn whenever the possibility o blood or body uid splashes may occur on the clothing.

•

Gloves must b e worn whenever there is a p ossib ility o touching b lood or b ody luids, and whenever there is a possibility o handling equipment or touching sur aces contaminated with blood or b ody luids.

•

Hands must also be washed/sanitized a ter removal o gloves and patient contact, and when changing rom contaminated gloves to a clean pair.

Exposure to in ectious microorganisms is a daily concern or healthcare pro essionals, especially with possible risk o exposure to HIV/AIDS, and HBV in ections. HIV-in ected individuals may be symptomless and go undiagnosed or 10 years or more, yet they are carriers o the in ection and have the potential to spread the disease. Epidemiologic studies indicate that HIV in ection 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 blood. Inanimate objects such as water ountains, telephone sur aces, or toilet seats cannot transmit HIV. Hepatitis B is another bloodborne in ection; it a ects the liver. It is thought that more than one million people in the United States have chronic hepatitis B and, as such, can transmit the disease to others. Because no symptoms may be evident in patients in ected with particular diseases, such as HIV/AIDS, and hepatitis B, all patients must be treated as potential sources o in ection rom blood and other body uids. T e practices associated with this concept are called standard precautions. T is rationale treats all body uids and substances as in ectious and serves to prevent the spread o microorganisms to other patients by the radiographer, as well as to protect the radiographer rom contamination. Body uids and substances that may be considered in ectious include blood, breast milk, vaginal secretions, amniotic uid, semen, peritoneal uid, synovial uid, cerebrospinal uid, eces, urine, secretions rom the nasal and oral cavities, and secretions rom the lacrimal and sweat glands. It is essential, then, that the radiographer makes the practice o blood and body uid precautions standard; that is, they must be practiced on all patients without exception. T is involves the use o personal protection equipment (PPE), or barriers, such as gowns and masks as indicated, to provide a separation between a patient’s blood and body uids and the radiographer or other healthcare worker. Special precautions must also be taken with the disposal o biomedical waste, such as laboratory and pathology waste, all sharp objects, and liquid waste rom suction, bladder catheters, chest tubes, and IV tubes, as well as drainage containers. Biomedical waste must be packaged in special, easily identi able, impermeable, puncture-proo containers and removed rom the premises by an approved biomedical waste hauler.

Healthcare-Associated Infections 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 may acquire some type o HAI. Hospital personnel can also become in ected (occupationally acquired in ection). It is somewhat surprising, yet understandable, that many in ections can be acquired in the hospital; surprising because hospitals are places where people go to regain their health, yet understandable because 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

CHAPTER 3 INFECTIO N CO NTRO L

in ection (U I), o en related to the use o urinary catheters, which can allow passage o pathogens into the patient’s body. Other types o HAIs include sepsis, wound in ection, and respiratory tract in ection. Healthcare practitioners must exercise strict in ection prevent and control precautions so that their equipment and/or technique will not be the source o HAI. Contaminated waste products, equipment such as emesis basins, tubing and catheters, soiled linen, and improperly sterilized equipment are all means by which microorganisms can travel. Not every patient will come in contact with these items; however, the healthcare pro essional is in constant contact with patients and is there ore a constant threat to spread in ection. Microorganisms are most commonly spread by way o the hands; spread o in ection can be e ectively reduced by proper disposal o contaminated objects and proper hand hygiene be ore and a er each patient. Disin ectants, antiseptics, and germicides are used in many hand-hygiene liquids to kill microorganisms.

Airborne Precautions

TRANSMISSION-BASEDPRECAUTIONS

They are used to prevent airborne disease transmission in the healthcare setting.

Adherence to standard precautions in the care o all patients will minimize the risk o transmission o HIV and other bloodborne and body substance–borne pathogens rom the patient to the radiographer and rom the radiographer to the patient. T e use o standard precautions also minimizes the need or category-speci c isolation. T ese have been replaced by transmission-based precautions: airborne, droplet, and contact ( able 3–1). Under these guidelines, some conditions/diseases can all into more than one category.

•

Patients are isolated in private rooms with special air handling and ventilation systems (negative pressure rooms). I a private room is not available, patients are cohorted.

•

Healthcare personnel must wear personal N95 respirators whenever they enter an airborne isolation room.

•

Patient transport must be limited as much as possible; when patient transport is essential, the patient must wear a surgical string mask.

•

Healthcare personnel must wear a surgical string mask when working within 3–6 t o a patient on droplet precautions.

Airborne Medical asepsis and blood and body uids precautions are used when per orming radiographic examinations on all patients, but additional precautions may be required when a patient is suspected or known to have a TABLE3–1. Transmission-Based Precautions Examples Airborne TB Varicella Rubeola Droplet Rubella Mumps In uenza Contact Mumps MDROs (antibiotic resistant organisms such as MRSA and VRE)

Protection • •

• •

• •

Patient: wears surgical string mask; private, negative-pressure room Radiographer: wears N95 particulate respirator mask i patient is not able to wear a mask, gloves; gown or blatant contamination Patient: wears surgical string mask; private room Radiographer: gown and gloves as indicated; surgical string mask i patient is not able to wear a mask, except or H1N1 In uenza when an N95 particulate respirator mask would be worn Patient: private room; wears mask i required by your acility Radiographer: gloves and gown; mask or MRSA, i required by acility

MRSA, methicillin-resistant Staphylococcus aureus.

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particular communicable disease. For example, airborne precaution is employed with patients suspected or known to be in ected with the tubercle bacillus (TB), chickenpox (varicella), and measles (rubeola). Airborne precaution requires the patient to wear a surgical string mask to avoid the spread o acid- ast bacilli (in bronchial secretions) or other pathogens during coughing, particularly i the patient must be transported. T e healthcare sta must wear personal N95 respirators whenever they enter an airborne isolation room. T is special mask requires periodic t testing. T ose who cannot be tted or a N95 mask may need to wear a PAPR (Powered Air Puri ying Respirator) instead. T e radiographer should wear gloves, but a gown is required only i agrant contamination is likely. Patients in ected with airborne diseases require a private, specially ventilated (negative-pressure) room ( able 3–1).

Droplet 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, and healthcare practitioners must wear a regular (string) mask to enter a droplet- precautions isolation room, except or H1N1 In uenza where an N95 particulate respirator mask may need to be worn instead, when involved in aerosol generating procedures.

Contact

Contact Precautions They are used to prevent contact transmission o disease in the healthcare setting.

•

Patients are isolated in private rooms or cohorted.

•

Healthcare personnel must use gloves and gowns as indicated to prevent unprotected exposure.

•

Hands must be disin ected be ore and a ter gloving.

•

Patient transport should be limited as much as possible; when necessary, special precautions are taken.

•

All x-ray imaging requires special precautions and two-radiographer teamwork.

•

Equipment should be dedicated to a single patient or cohort, or equipment must be cleaned and disin ected between patients.

Any disease spread by direct or close (indirect) contact, such as MRSA (methicillin-resistant Staphylococcus aureus), Clostridium di cile, and some wounds, requires contact precautions. Contact-precaution procedures require a private patient room, and the use o gloves and gown or anyone coming in direct contact with the in ected individual or the in ected person’s environment. Some acilities may require healthcare workers to wear a mask when caring or a patient with MRSA. Patients in contact isolation occasionally have to be transported to the radiology department or examination. When this is the case, the department should be noti ed rst in order to prepare properly. T e patient should wash his or her hands rst i possible. T e wheelchair or stretcher should rst be covered with a clean sheet, ollowed by a second sheet or thin blanket to cover the patient. T e radiographic room should be available and ready or the patient to be taken in directly. T e x-ray table should be covered with a clean sheet be ore the patient is trans erred to it. One radiographer (wearing gloves) must be responsible or patient positioning and the other or equipment controls and operation (to avoid contamination o equipment and possible transmission o disease to others via indirect contact or omites). A er the examination is completed, the patient is trans erred to the wheelchair or stretcher and transported back to their room. Any contaminated linens should be placed in an appropriate linen hamper and contaminated disposables such as tissues are placed in a separate trash receptacle or disposal.

CHAPTER 3 INFECTIO N CO NTRO L

T e radiographic table and other equipment should be cleaned with a disin ectant while wearing gloves. Hands should be care ully washed a er glove removal at the completion o the task. Mobile radiography per ormed on patients on contact isolation generally requires special precautions and the teamwork o two radiographers. T e rst (or “dirty”) radiographer dons gown, gloves (gloves must cover gown cu s), and mask (i indicated), usually available just outside the patient’s room. T e necessary image plates must be placed in a plastic bag or pillowcase to protect them rom contamination. T e radiographer must remember to bring an extra pair o gloves into the patient room. T e mobile x-ray unit is brought into the room, and all possible adjustments must be made and/or covers applied be ore the radiographer touches anything else. T e equipment and IP are positioned, and the patient is adjusted properly. At this point, the mobile x-ray unit must not be touched until the radiographer disposes o the gloves he or she has on, cleanses their hands, and replaces them with the clean extra pair. T e exposure is then made; the covered IP is removed rom behind/ under the patient and brought to the door. T e “dirty” radiographer slides the pillowcase or plastic cover away rom the IP and the second member o the team (the “clean” radiographer) grasps the uncovered IP. Just inside the patient room door, the contaminated gloves should be removed properly, then the gown ties untied and the gown removed by olding the gown orward (with the dirty sur aces touching) and pulling the sleeves inside out rolling the gown into a ball with the clean side now on the outside o the rolled gown. T e mask, i worn, may now be removed by untying strings and removing without touching the ront sur ace o the mask. T e discarded garments must be placed in the container provided. T e radiographer should then care ully wash/sanitize his or her hands, dry them with paper towels, and take care not to touch the aucets. A er leaving the room, the mobile unit must be thoroughly cleaned with a disin ectant while wearing gloves and then hands care ully washed/sanitized a er glove removal at the completion o this task. It should be noted that these patients may eel ostracized and relegated to a kind o solitary con nement. T e radiographer must remember that these patients have the same needs as other patients (indeed, perhaps greater needs) and be certain to treat them with dignity and care.

Patients Whose Immune Systems Are Compromised T e purpose o protective, or reverse, isolation is to keep the susceptible patient/patients whose immune system is compromised (immunosuppression) rom becoming in ected. Patients su ering rom burns, who have lost their means o protection, their skin, have increased susceptibility to bacterial invasion. Patients whose immune systems are compromised (e.g., transplant recipients, leukemia, chemotherapy) are unable to combat in ection and are more susceptible to in ection. T ese patients are treated with strict isolation technique, taking care to protect the patient rom contamination. T e teamwork o two radiographers is also required or care o the patient with compromised immune system, although the purpose and procedure are largely opposite that o the other isolation categories.

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Preparation or cleanliness and hygiene start be ore entering the patient room. T e “clean” radiographer touches only the patient and that which comes in contact with the patient.

Contaminated Material Disposal Special precautions must be taken with the disposal o biomedical waste, such as laboratory and pathology waste, used bandages and dressings, discarded gloves, all sharp objects, and liquid waste rom suction, bladder catheters, chest tubes, and IV tubes, as well as drainage containers. Biomedical waste must be packaged in special, easily identi able, impermeable bags and removed rom the premises by an approved biomedical waste hauler.

Summary • Because no symptoms may be evident in patients af icted with certain diseases such as HIV/AIDS, and hepatitis B, all patients must be treated as potential sources o in ection rom blood and other body uids; this is the standard precautions concept. • T e practice o standard precautions and transmission-based precautions helps prevent spread o in ection to the healthcare pro essional and to other patients. • In ections acquired in hospitals are called healthcare-associated in ections (HAIs) or nosocomial in ections; the most common HAI is urinary tract in ection (U I). • T e healthcare pro essional is legally and ethically responsible or adhering to standard precautions principles; they must be practiced on all patients at all times without exception. • Biomedical waste (body substances and their containers) must be disposed o in care ully controlled circumstances. • ransmission-based precautions include airborne, droplet, and contact. • Airborne precaution requires that the patient wear a surgical string mask and be admitted to a private, specially ventilated, negativepressure room. • Droplet precaution and a private room are required or German measles, mumps, and in uenza; the radiographer requires a surgical string mask (i the patient is not wearing one) and may also need to wear gown and gloves. An N95 particulate respirator mask may be required during an aerosol generating procedure on a patient with H1N1 in uenza. • Contact precaution (C. di cile, MRSA, some wounds) requires that the radiographer use mask, gown, and gloves when in direct contact with the patient. • Radiography o a patient with contact precaution requires the teamwork o two radiographers. • Protective, or reverse, isolation is used to keep the susceptible patient rom being in ected.

CHAPTER 3 INFECTIO N CO NTRO L

COMPREHENSION CHECK Congratulations! You have completed your review o this chapter. I you are able to answer the ollowing group o comprehensive questions, you can eel con dent that you have mastered this section. You are then ready to go on to “Registry-type”questions that ollow. For greatest success, do not go to these multiple-choice questions without rst completing the short-answer questions below. 1. List three disin ectant agents (p. 34). 2. Describe the correct method o handwashing, including when hands should be washed, opening/closing aucets, position o hands and orearms (p. 34).

14. Dif erentiate between medical and surgical asepsis (p. 34). 15. Identi y and explain the most important practice in good aseptic technique (p. 34). 16. Discuss the unction o uni orms worn by healthcare practitioners; the hazards o jewelry and nail polish (p. 34). 17. List the three types o transmission-based precautions (p. 36, 39– 41).

3. De ne pathogen, discuss types o pathogens (p. 33–35).

18. Explain the precautionary measures taken in airborne precaution regarding apparel (and or whom) and patient room (p. 36).

4. Describe the importance o the radiographer’s personal care, related to disease control (p. 34).

19. List three communicable diseases spread by droplet contact that require droplet precaution (p. 36).

5. Identi y and dif erentiate between the three basic means o transmitting in ectious microorganisms (p. 36).

20. Describe the method o per orming mobile chest radiography on patients with contact precaution, to include (p. 41, 42):

6. List three means o indirect transmission o pathogenic microorganisms (p. 36).

A. Number o persons needed

7. Identi y the most common type o acquired in ection (p. 38–39).

C. How to protect IPs rom contamination

hospital-

8. List ve possible sources o HAI in ection in the radiology department (p. 39). 9. Describe precautions used to prevent airborne disease transmission (p. 39).

B. Radiographer’s apparel D. Why an extra pair o gloves is needed in the patient room E. Role played by the second individual F. How protective clothing should be removed

10. Identi y the means by which microorganisms are spread (p. 39, 40).

G. Care o x-ray machine at completion o examination

11. What substances are added to handwashing liquids to kill microorganisms (p. 36)?

21. Describe the proper method o transporting a contact-precaution patient to the radiology department (p. 40).

12. Discuss the rationale o (p. 38, 39).

standard precautions

13. Discuss each o the ollowing with respect to standard precautions (p. 39, 40): A. When a ace shield should be used B. When appropriate PPE should be used C. When hands should be washed D. When gloves should be used E. How body uid and substance spills should be cleaned F. Care o used needles G. Special devices available or CPR H. On whom standard precautions should be practiced

22. Describe the purpose o protective isolation (p. 41). 23. Discuss any special needs the isolation patient may have (p. 41). 24. What is biomedical waste and how must it be cared or (p. 38)?

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PART I PATIENT CARE AND EDUCATIO N

CHAPTER REVIEW QUESTIONS 1. Pathogens are: 1. Always harm ul

6. What is the name o the practice that serves to retard the growth o pathogenic bacteria?

2. Sometimes harm ul

(A) Antisepsis

3. Capable o producing disease

(B) Bacteriogenesis

(A) 1 only

(C) Sterilization

(B) 2 only

(D) Disin ection

(C) 1 and 3 only (D) 2 and 3 only 2. Diseases that can be transmitted by direct contact include:

7. Which o the ollowing diseases require(s) airborne precaution? 1. TB 2. Varicella

1. Skin in ections

3. Rubella

2. Syphilis

(A) 1 only

3. Malaria

(B) 1 and 2 only

(A) 1 only

(C) 3 only

(B) 1 and 2 only

(D) 1, 2, and 3

(C) 2 and 3 only (D) 1, 2, and 3 3. In which o the ollowing conditions is protective, or reverse, isolation indicated? 1. Transplant recipient 2. Chemotherapy recipient 3. Leukemia (A) 1 only (B) 1 and 2 only (C) 2 and 3 only (D) 1, 2, and 3 4. Which o the ollowing is/are means o transmission o microorganisms?

8. The radiographer must per orm the ollowing procedure(s) be ore entering an isolation room with a mobile x-ray unit: 1. Wear gown and mask 2. Wear gown, gloves, and possibly mask 3. Clean the mobile x-ray unit (A) 1 only (B) 2 only (C) 1 and 3 only (D) 2 and 3 only 9. Lyme disease is a condition caused by bacteria carried by deer ticks. The tick bite may cause ever, atigue, and other associated symptoms. This is an example o transmission o an in ection by:

1. Vector

(A) Droplet contact

2. Fomite

(B) The airborne route

3. Airborne

(C) A vector

(A) 1 only

(D) A vehicle

(B) 1 and 2 only (C) 3 only (D) 1, 2, and 3 5. What is the single most ef ective means o controlling the spread o in ectious microorganisms?

10. Which o the ollowing can be transmitted via in ected blood? 1. TB 2. AIDS 3. HBV

(A) Wearing gloves

(A) 1 only

(B) Wearing masks

(B) 1 and 2 only

(C) Handwashing

(C) 2 and 3 only

(D) Sterilization

(D) 1, 2, and 3

CHAPTER 3 INFECTIO N CO NTRO L

Answers and Explanations 1. (D) Pathogens are causative agents—microorganisms capable o producing disease. Pathogens termed opportunistic are usually harmless, but can become harm ul i introduced into a part o the body where they do not normally reside, or when introduced into an immunocompromised host. Bloodborne pathogens reside in blood and can be transmitted to an individual exposed to the blood or body uids o the exposed individual. Common bloodborne pathogens include hepatitis C virus (HCV), hepatitis B virus (HBV), and human immunode ciency virus (HIV). Because radiography o ten involves exposure to sickness and disease, the radiographer must be aware o , and conscientiously practice, in ection prevention and control, measures. 2. (B) In ectious microorganisms can be transmitted rom one patient to other patients or to healthcare workers, and rom healthcare workers to patients. They 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, MDROs, and sexually transmitted diseases such as syphilis. 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 on dust and settle on intermediate objects such as clothing, utensils, or ood. Patients with respiratory tract in ections and diseases transported to the radiology department, thereore, should wear a mask to prevent such transmission during a cough or sneeze; it is not necessary or the healthcare pro essional or transporter to wear a mask (as long as the patient does). Many such microorganisms can remain in ectious while awaiting transmission to another host. A contaminated inanimate object such as a ood utensil, doorknob, or intravenous (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 (e.g., rabies; although the rabid animal is the vector, rabies is contracted by contact), a mosquito that carries malaria, or a tick that carries Lyme disease. 3. (D) Protective, or reverse, isolation is used to keep the susceptible patient rom becoming in ected. Burn patients who have lost their means o protection (their skin) have increased susceptibility to bacterial invasion. Protective isolation is particularly important in caring

or immunode cient patients such as those who have received chemotherapy, transplant recipients, leukemia patients . . . they are unable to combat in ection and are more susceptible to in ection. These patients are treated with strict isolation technique, i.e. taking care to protect the patient rom contamination. 4. (D) Microorganisms can be transmitted via droplet, airborne, and contact (direct or indirect). Other sources o transmission are vehicle and vector. Pathogenic microorganisms expelled rom the respiratory tract through the mouth or nose can be carried as evaporated droplets through the air or on dust and settle on clothing, utensils, or ood. A contaminated inanimate object such as a pillowcase, x-ray table, 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 (rabies), a mosquito that carries malaria, or a tick that carries Lyme disease. 5. (C) Healthcare practitioners must exercise strict in ection control precautions so that they or their equipment will not be the source o healthcare-associated in ections (HAIs). Contaminated waste products, soiled linen, and improperly sterilized equipment are all means by which microorganisms can travel. Not every patient will come in contact with these items; however, the healthcare pro essional is in constant contact with patients and is there ore a constant threat to spread in ection. Microorganisms are most commonly spread by way o the hands; there ore, handwashing/sanitizing be ore and a ter each patient is the most ef ective means o controlling the spread o microorganisms. Disin ectants, antiseptics, and germicides are used in many handwashing liquids to kill microorganisms. 6. (A) Antisepsis retards the growth o pathogenic bacteria. Alcohol is an example o an antiseptic. Medical asepsis re ers to the destruction o pathogenic microorganisms through the process o disin ection. Examples o disin ectants are hydrogen peroxide, chlorine, and boric acid. Surgical asepsis (sterilization) re ers to the removal o all microorganisms and their spores (reproductive cells) and is practiced in the surgical suite. Bacteriogenesis re ers to the ormation o bacteria. 7. (B) Airborne precaution is employed with patients suspected or known to be in ected with the tubercle bacillus (TB), chickenpox (varicella), and measles (rubeola). Airborne precaution requires the patient to wear a surgical string mask to avoid the spread o acid- ast bacilli (in

45

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PART I PATIENT CARE AND EDUCATIO N

bronchial secretions) and other pathogens during coughing. I the patient is unable or unwilling to wear a mask, the radiographer must wear one. An N95 particulate respirator is the mask required or healthcare workers. The radiographer should wear gloves, but a gown is required only i agrant contamination is likely. Patients with airborne precautions require a private, specially ventilated (negative pressure) room (Table 3–1). 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. The pathogenic droplets can in ect others when they come in contact with mouth or nasal mucosa or conjunctiva. Rubella (“German measles”), mumps, and in uenza are among the diseases spread by droplet contact; a private room is required or the patient, and healthcare practitioners must wear a mask. An N95 particulate respirator mask may be required while a patient with H1N1 is receiving an aerosol generating procedure. 8. (B) When per orming bedside radiography in an isolation room, the radiographer should wear a gown, gloves, and sometimes a mask. The 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,” while the other handles the patient. The mobile unit should be cleaned with a disin ectant be ore exiting the patient’s room. 9. (C) Lyme disease is a condition that results rom transmission o an in ection by a vector (“deer”tick). Vectors are insects and animals carrying disease. Droplet contact involves contact with secretions ( rom the nose, mouth) that travel via a sneeze or cough. Airborne route involves evaporated droplets in the air that trans er disease. 10. (C) Epidemiologic studies indicate that HIV/AIDS (acquired immunode ciency syndrome) can be transmitted only by intimate contact with blood or body uids o an in ected individual. This can occur through the sharing o contaminated needles, through sexual contact, rom mother to baby at childbirth, and rom trans usion o contaminated blood. Inanimate objects cannot transmit HIV and AIDS. HBV is another bloodborne in ection and af ects the liver. It is thought that more than one million people in the United States have chronic hepatitis B and, as such, can transmit the disease to others. Acid- ast bacillus isolation is employed with patients suspected or known to be in ected with the TB. Acid- ast bacillus isolation requires that the patient wear a mask to avoid the spread o acid- ast bacilli (in bronchial secretions) during coughing.

Patient Monitoring, Medical Emergencies, and Pharmacology

4

Object ives At the conclusion o this chapter, the student will be able to: • • • • • • • •

Discuss the value o complete and accurate patient assessment. Discuss actors and conditions that can a ect vital sign norms. Explain the use o various oxygen delivery systems. Identi y the use o various tubes and central lines. De ne terms related to allergic reactions. List the various routes o medication administration. Identi y the types o contrast media and cite examples o their usage. Describe the levels o contrast media untoward responses.

ROut ine MOnit ORing T e radiographer assesses a patient’s condition be ore bringing the patient to the radiographic department and must continue to be alert to patient condition, and any possible change in condition, as the examination proceeds. Assessment begins with a review o the patient’s chart; use ul in ormation includes the admitting diagnosis, nurses’ notes, the patient’s degree o ambulation, preparation or the radiologic procedure and its e ectiveness, results o laboratory tests, any requirements or collecting the patient’s urine, etc. T e radiographer obtains a brie pertinent clinical history, and assesses the patient’s condition by observing and listening. Facts are gathered or the purpose o obtaining in ormation use ul in providing adequate care and accurate diagnosis. o provide sa e and e ectual care, the radiographer will assess the severity o any traumatic injury, degree o motor control, and any need or support equipment or radiographic accessories. Is the patient able to move? Can the patient be imaged more e ectively and/or less pain ully on the stretcher or in the wheelchair? Can the use o sponges, sandbags, or other x-ray accessories result in a more com ortable, sa e, and diagnostic examination?

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Pa r t I Pa t Ie n t Ca r e a n d e d u Ca t Io n

Vital Signs

Vital Signs

• • • •

Temperature Pulse Respiration Blood pressure

Normal Body Temperatures Adult Oral Rectal Axillary Infant to age 4 years Child aged 5–13 years

98.6°F 99.1°–99.6°F 97.6°–98.1°F 97.9°–100.4°F 97.8°–98.6°F

Vital signs can provide crucial in ormation about an individual state o health. T e radiographer employed in an o ce environment o en nds vital signs measurement part o their routine duties. T e radiographer can also be required to assist in an emergency situation by obtaining patient’s vital signs. Although not a routine unction o radiographers, they should be pro cient and con dent i and when the need arises. Regular review and practice is essential. Obtaining vital signs involves the measurement o body temperature, pulse rate, respiratory rate, and arterial blood pressure. Routine monitoring o patient’s condition, physical signs, and vital signs are discussed in Chapter 2. Routine and continuous monitoring o patient’s condition is essential, so that any change in condition can be addressed be ore it becomes a medical emergency. In review, obtaining vital signs involves the measurement o body temperature, pulse rate, respiratory rate, and arterial blood pressure. Elevated body temperature, or ever, o en signi es in ection. Symptoms include malaise; increased pulse and respiratory rates; f ushed, hot, and dry skin; and occasional chills. Body temperature is usually obtained using an oral thermometer placed under the patient’s tongue, which provides a digital reading. Normal body temperature varies rom person to person depending on several actors, including age. Normal adult body temperature taken orally is 98.6°F (37°C). Rectal temperature is generally 0.5°F to 1.0°F higher, whereas axillary temperature is usually 0.5°F to 1.0°F lower. Slight variation o 0.5°F to 1.0°F is generally considered within normal limits. Body temperature is usually lowest in the early morning and highest at night. In ants and children have a wider range o body temperature than adults; the elderly have lower body temperatures than others. Super cial arteries are best suited or determination o pulse rate, though the pulse can be measured at any large artery. T e pulse rate should be counted or 30 seconds and multiplied by two. Attention should be given to pulse regularity and volume. T e ve most easily palpated pulse points are the radial, carotid, temporal, emoral, and popliteal pulse. T e radial pulse is the most requently used. T e apical pulse, at the apex o the heart, can be evaluated with the use o a stethoscope. Respirations should be counted a er counting the pulse rate while still holding the patient’s wrist. Respirations should be counted or at least 30 seconds; 15-second counting multiplied by our can result in a airly large error. T e normal respiratory rate is 12 to 18 breaths/min. T e respiratory rate o young children is higher, up to 30 breaths/min. Although the radiographer is counting respirations, he or she should be assessing the respiratory pattern (even, uneven) and depth (normal, shallow, deep) as well. Blood pressure measures the degree o orce applied to arterial walls as the heart pumps blood throughout the body. It is measured using a mercury-based manometer and read in millimeters o mercury (mm Hg). As with other vital signs, the measurement is made with the patient seated and having rested or about ve minutes prior to measurement. Normal adult systolic pressure ranges between 100 and 140 mm Hg; the normal diastolic range is between 60 and 90 mm Hg.

Ch a Pt e r 4 Pa t Ie n t Mo n It o r In G, Me d ICa L e Me r Ge n CIe S, a n d Ph a r Ma Co Lo GY

Physical Signs/Symptoms T e radiographer should always be alert o a patient’s appearance and condition. Awareness o patient gross and ne motor control is critical in order to avoid patient injury. Gross/general motor control re ers to basic body movement and locomotion, such as walking or waving one’s arm. Fine motor control involves the coordination o bones, muscles, and nerves to produce smaller and more precise movements/tasks such as zipping a zipper or grasping and writing with a pencil. Conditions o the brain, spinal cord, nerves, muscles, and bony articulations (such as in Parkinson’s disease) impair ne motor control. Any sudden changes such as changes in the color, temperature, and moistness o the patient’s skin should be noted. Paleness can indicate weakness; the diaphoretic patient has pale, cool skin; ever is requently accompanied by hot, dry skin; “sweaty” palms might indicate anxiety, a patient who is cyanotic (bluish lips, mucous membranes, nail beds) needs oxygen and requires immediate attention. Chronic obstructive pulmonary disease (COPD) patients receive low f ow rates o oxygen; acute exacerbations are managed with inhaled bronchodilators. Respiration delivers oxygen to all body cells and rids the body o carbon dioxide. T e radiographer should recognize abnormalities or altered respirations o the patient. T e term describing di cult breathing is dyspnea. More speci c terms used to describe abnormal respirations include uneven, spasmodic, strident (shrill, grating sound), stertorous (labored, e.g., snoring), tachypnea (abnormally rapid breathing), orthopnea (di culty breathing while recumbent), and oligopnea (abnormally shallow, slow). Chronic respiratory conditions such as emphysema should be noted by the radiographer during patients’ assessment. Some patients’ conditions require the upper body to be elevated or easier breathing; the term orthopnea describes di culty breathing while recumbent. Any change in breathing should alert the radiographer o possible onset o respiratory distress. T e pulse is elt as a result o regular expansion and contraction o an artery as waves o blood travel through arteries; the pulse elt over arteries is in time with the heart beat as the le ventricle contracts. T e average normal adult pulse rate is between 60 and 100 beats/min. T e term tachycardia describes an abnormally ast pulse rate; it can be temporary as a result o exertion or excitement or can be caused by heart disease. Resting pulse is aster in ebrile, anemic, or hypovolemic patients, as well as patients who experience shock. An abnormally slow pulse rate is termed bradycardia and can result in inadequate circulation o blood to the brain, coronary arteries, and other essential organs. Pulse rate depends on the person’s age, sex, body exertion and position, and general state o health. Children and the elderly have higher pulse rates. T e pulse rate increases in the standing position and a er exertion. T e pulse rate also increases with certain conditions, such as ever, organic heart disease, shock, and alcohol and drug use. Pulse rates vary between men and women and among adults, children, and in ants; athletes o en have lower pulse rates. Blood pressure can vary with age, sex, atigue, mental or physical stress, disease, and trauma. Blood pressure is greatest during ventricular systole

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Pa r t I Pa t Ie n t Ca r e a n d e d u Ca t Io n

Blood Pressure Is Af ected by

• • •

Cardiac output Blood volume Vascular resistance

Blood Pressure

• • •

Measured using sphygmomanometer and stethoscope Cu in ation su cient to collapse the brachial artery First sound heard is systolic pressure

Common Pulse Points Artery

Location

Radial Carotid Temporal Femoral Popliteal

Wrist; at base of thumb Neck; just lateral to midline In front of upper ear Inguinal region; groin Posterior knee

(contraction) and lowest during diastole (relaxation). Blood pressure measurements are recorded with the systolic pressure on top and the diastolic pressure on the bottom, as in 100/80 (read “one hundred over eighty”). Normal adult systolic pressure ranges between 100 and 140 mm Hg; the normal diastolic range is between 60 and 90 mm Hg. Blood pressure consistently more than 140/90 is considered hypertension. Prehypertension is present when systolic measurements are between 120 and 140 mm Hg and/or between 80 and 90 mm Hg diastolic pressure. Blood pressure consistently more than 140/90 is considered hypertension. Le undiagnosed and untreated, hypertension can lead to renal, cardiac, or brain damage. Hypotension is characterized by a systolic pressure o less than 90 mm Hg. Hypotension can be seen in individuals with decreased blood volume as a result o hemorrhage, in ection, ever, and anemia. Orthostatic hypotension occurs in some individuals when they rise quickly rom a recumbent position.

Documentation T e chart o a hospitalized patient is a collection o in ormation, records, and laboratory and imaging reports. In ormation includes the patient’s condition, progress, medications, treatments, etc. Documentation required o the radiographer should be entered directly on the patient’s examination requisition, or in the radiology computer system notes. Notes are made regarding pertinent patient history, patient’s illness, or injury. Any incident, accident, or unusual occurrence that causes injury or potential injury/harm to the patient (or visitor, or sta ) must be reported to a radiology supervisor and an incident report completed. T is is very important or the hospital’s risk management department— or liability considerations and or possible procedural alterations to prevent uture similar incidents. Note should always be made regarding any unusual, though very minor, occurrence that might not require an incident report. A supervisor should always be consulted to make that decision.

Pat ient suPPORt equiPMent Oxygen One o human being’s most basic physiologic needs is an adequate supply o oxygen. Diminished oxygen supply (hypoxia) can result rom an airway obstructed by aspirated material, laryngeal edema as a result o anaphylaxis, or a pathologic process such as emphysema. T e radiographer must be knowledgeable enough to recognize symptoms and respond appropriately. T e proper response to respiratory distress might be to per orm the Heimlich maneuver, to summon the code team, or to check the f ow o oxygen already in place. 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 can die. Oxygen may be required in cases o severe anemia, pneumonia, pulmonary edema, and shock.

Ch a Pt e r 4 Pa t Ie n t Mo n It o r In G, Me d ICa L e Me r Ge n CIe S, a n d Ph a r Ma Co Lo GY

Symptoms o inadequate oxygen supply include dyspnea, cyanosis, diaphoresis, and distention o the veins o the neck. A 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 di cult), and have oxygen and emergency drugs available. In areas that patients will occupy or extended periods (e.g., patient department, operating room, emergency department, and radiology department), oxygen is available through wall outlets at a pressure o 60 to 80 psi (pounds per square inch) equipped with an easily adjustable f owmeter to regulate the administration o oxygen. It is important to administer humidi ed oxygen to avoid drying and irritation o the respiratory mucosa. In other areas, oxygen will be available in tanks having one valve to regulate its f ow and another to indicate the amount o oxygen remaining in the tank. Conditions o en requiring oxygen therapy are COPD, pneumonia, severe asthma, cystic brosis, sleep apnea, and others. T ere are various devices available to deliver oxygen to patients. T eir use is determined by the amount o oxygen required by the patient. T ey are requently classi ed as low or high ow. COPD patients require low f ow therapy; high f ow delivery can result in apnea. T e nasal cannula is the most requently used device and is used to supplement the oxygen in room air; its short prongs extend approximately 1 cm into the nares. T e nasal cannula is a low f ow small percentage oxygen device. It is convenient and airly com ortable or the patient, although it can be somewhat easily moved out o position, or example, during sleep. T ere are various types o oxygen masks available or delivery o oxygen. T e Venturi mask mixes oxygen with room air and can deliver speci c (usually, high f ow) concentrations o oxygen. T e simple ace mask (low f ow) is best suited or short-term oxygen therapy. With extended use, the plastic becomes warm and sticky. Communication is di cult, the mask is easily displaced, and it must be removed at mealtime. T e partial rebreathing mask (low f ow) and non-rebreathing mask (low f ow) deliver more precise concentrations o oxygen to the patient. Mechanical ventilators (high f ow) are most requently encountered in a hospital critical care unit. Patients on ventilators have an arti cial airway in place, whereas the ventilator controls the respiratory rate and volume. Although oxygen is not a f ammable substance, it does support combustion (i.e., materials burn more readily in its presence), so care must be taken to avoid spark or f ame where oxygen is in use. No one should ever smoke in an area where oxygen is in use. Oxygen canisters must be kept away rom all inf ame. T e use o petroleum-based lotion/ cream should be avoided because petroleum is a highly f ammable mixture o hydrocarbons; rather, water-based products should be used instead.

Suction T e use o a suction device is occasionally required to maintain a patient’s airway by aspirating secretions, blood, or other f uids. Suctioning may be

Normal Pulse Rates (beats/min) Men Women Children Infants

68–75 72–80 70–100 100–160

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Pa r t I Pa t Ie n t Ca r e a n d e d u Ca t Io n

indicated when the patient is unconscious, when secretions have high volume or viscosity, when coughing is ine ective or when the individual is otherwise unable to clear their airway. Suction is available rom a wall outlet, similar to oxygen, or as a mobile apparatus. It is unlikely that the radiographer would be required to suction the tracheobronchial tree, but he or she might be needed to assist with the procedure. Suction tubing must have a disposable catheter attached to its end or collection o airway secretions. It is essential to use the correct diameter catheter; too large a diameter can result in airway occlusion, leading to hypoxia and or/and atelectasis when suction is applied. T e radiographer should be amiliar with the location o suction equipment and replacement o disposable catheters.

Intravenous Equipment and Venipuncture Needles

•

Gauge: identi es diameter of needle bore/lumen

• • •

Larger gauge: smaller bore diameter Smaller gauge: larger bore diameter Hub: part of needle attached to syringe or IV tube

Intravenous f uids and/or medication are administered to meet speci c patient needs. Medications administered intravenously result in rapid patient response; medications are o en delivered in this ashion in emergency and critical situations. Patients who are dehydrated and require f uid and electrolyte replacement will have these (normal saline or D5W) administered intravenously. Intravenous (IV) equipment includes needles, syringes, f uids such as normal saline or D5W (a solution o 5% dextrose in water), IV catheters, heparin locks, IV poles, and in usion sets. T e diameter o a needle is identi ed as its gauge. As the gauge increases, the bore becomes smaller. Hence, a 23-gauge needle has a smaller diameter bore than an 18-gauge needle. Hypodermic needles are generally used or phlebotomy, whereas butterf ies and IV catheters are used more requently or injections such as contrast media. I an in usion injection is required, an IV catheter is generally pre erred. T e hub o the hypodermic needle is attached to a syringe, whereas the hub o the butterf y tubing or IV catheter may be attached to a syringe or an IV container via an IV in usion set. Medication or contrast material is o en mixed with normal saline or D5W. Some IV medications are given at intervals through an established heparin lock. A heparin lock consists o a venous catheter established or a certain length o time to make a vein available or medications that have to be administered at requent intervals. T is helps prevent the ormation o scarred, sclerotic veins as a result o requent injections at the same site. When repeated administrations o medication are needed, an IV catheter is o en used. T is is a twopart device consisting o a solid (without a bore) needle and a f exible plastic catheter. A er the needle is introduced into the vein, the catheter is advanced over the needle, secured with tape, and the needle removed. T e IV container should be hung 18 to 24 inch above the level o the vein. I placed lower than the vein, the solution will stop f owing and blood will return into the tubing. I hung too high, the solution can run too ast. Occasionally, the position o the needle or catheter in the vein will a ect the f ow rate. I the bevel is adjacent to the vessel wall, f ow may decrease or stop altogether. O en, just changing the position o the patient’s arm will remedy the situation.

Ch a Pt e r 4 Pa t Ie n t Mo n It o r In G, Me d ICa L e Me r Ge n CIe S, a n d Ph a r Ma Co Lo GY

Ce pha lic ve in Ce pha lic ve in Ba s ilic ve in Ba s ilic ve in

Acce s s ory ce pha lic ve in Ce pha lic ve in

Me dia n cubita l ve in

S upe rficia l dors a l ve ins

Ba s ilic ve in

Dors a l ve nous ne twork

A

B

Figure 4–1. Veins commonly used for venipuncture. (A) Anterior aspect right forearm. (B) Dorsal aspect left hand.

T e term extravasation re ers to medication or contrast medium that has leaked rom a vein rupture or has been inadvertently introduced into tissue outside the vein. T e term in ltration re ers to the di usion o the injected material urther into adjacent tissues. T e needle should be removed and pressure applied to prevent ormation o a hematoma. T e recommended treatment is that the a ected extremity be elevated above the heart and cold compresses applied topically. Extravasation o small amounts o contrast agent will cause some pain, minimal swelling, and localized erythema that rapidly decreases. T e patient should be re erred to the emergency department i there is any skin blistering, increasing pain, etc. I larger volumes o contrast are extravasated, extensive tissue and skin necrosis can occur. T e antecubital vein is the most commonly used venipuncture site or contrast medium administration. It is not used or in usions that take longer than 1 hour because o its location at the bend o the elbow. T e basilic vein, located on the dorsal sur ace o the hand, is used when the antecubital vein is inaccessible. T e cephalic vein may also be used (Fig. 4–1). A warm compress can be applied to the area o intended injection to increase the area o blood circulation and improve access to the intended vein. T e needle is inserted into the vein at a 15-degree angle; blood will f ow back into the tubing when the needle is correctly positioned. Strict aseptic technique must be used or all IV injections. T ere are battery-powered peripheral “vein- nder” devices available commercially. T ey use high-intensity LED lights to transilluminate the patient’s subcutaneous tissue; in so doing, the device highlights the veins via their absorption (rather than ref ection) o the light. T ese devices can be particularly use ul or locating hard-to- nd veins in obese adults, in ants, and small children.

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Needle position or subcutaneous injection: Injection Site

Needle Angle

Subcutaneous

45°

Intravenous

15°

Intramuscular

90°

45°

Needle position or intravenous injection:

15° Skin Fat Vein Mus cle

Needle position or intramuscular injection:

90°

Tubes Following thoracotomy or other thoracic surgery, a chest tube may be put in place or the purpose o treating pneumothorax or hemothorax (removing air and/or f uid rom the pleural space). T e chest drainage system usually has three compartments: one is the suction control chamber, another is the collection chamber, and the third is the water seal chamber, which prevents atmospheric air rom entering the chest cavity. T e drainage system must always be kept below the level o the patient’s chest. Radiographers might encounter chest drainage systems when perorming mobile radiographic examinations on postsurgical patients. T e radiographer must be care ul not to disturb chest tubes during patient or equipment manipulation, and to immediately report any sudden change

Ch a Pt e r 4 Pa t Ie n t Mo n It o r In G, Me d ICa L e Me r Ge n CIe S, a n d Ph a r Ma Co Lo GY

in the patient’s condition and/or patient’s complaint o chest pain or discom ort. Gastrointestinal (GI) tubes can be nasogastric (NG), nasointestinal (NI), or nasoenteric (NE). NG tubes, such as the Dobho tube, are used as eeding tubes or patients whose condition prevents normal swallowing. NI/NE tubes can be used ollowing digestive tract surgery to remove gastric f uids and/or air (decompression; e.g., Levin and Salem-Sump tubes). NG and NI/NE tubes may be single or double lumen and can sometimes be temporarily disconnected or radiographic examinations. T e single-lumen NG or NI/NE tube can be clamped, but the doublelumen tube must never be clamped. I clamped, the walls o the doublelumen tube could adhere permanently. Instead, the tip o a syringe is inserted into the lumen and the syringe and tube then pinned (open side up) to the patient’s gown. Care must be taken not to disturb the placement o the GI tube. Examples o single-lumen NE tubes are the Cantor and Harris tubes; the Miller–Abbott tube is a double-lumen NE tube. T e Sengstaken–Blakemore tube is a triple-lumen tube having a gastric balloon, an esophageal balloon, and a gastric suction port; it is o en used in the treatment o bleeding esophageal varices. T ere are a number o specialized tubes/catheters used to provide regular or continual access to the circulatory system long-term care requirements such as dialysis, blood trans usion, drug therapy such as chemotherapy, and parenteral nutrition. T ey can also be used or laboratory blood draws and or monitoring central venous pressure (CVP). T ese are re erred to as central venous catheters (CVC or central lines). Examples o these central lines include the Port-A-Cath, the Hickman, the Raa , and the PICC. For x-ray veri cation o position placement, they usually have a radiopaque distal tip. T e distal tip should be located in the superior or in erior vena cava near the right atrium. During mobile radiography o the chest or tube placement, it is o en necessary to move the radiopaque external wires out o the way as much as possible to avoid arti acts that can inter ere with accurate diagnosis. Central Lines Classif ca tio n

Pu rp o se

Exa m p le

Short-term, external/ nontunneled Long-term, external/ nontunneled Long-term, tunneled

Admin med, draw blood, monitor RA BP Admin med, draw blood

PICC, CVC

Parenteral nutrition, dialysis

Hickman, Raaf

Long-term implanted venous access

Chemotherapy, blood transfusion

Port-A-Cath

PICC

Urinary catheterization may be employed postsurgically to assist in the healing o tissues or to assist an incontinent patient in the elimination o urine. It is essential that equipment used or the catheterization procedure is sterile, and that subsequent care is given to the catheterized patient to prevent in ection, as urinary tract in ections (U Is) account or the greatest number o nosocomial in ections. Urinary catheters are made o plastic, rubber, polyvinylchloride (PVC), and silicone. T e type

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selected is dependent on how long it is expected to remain in the bladder. Plastic and rubber are generally employed or short-term use, whereas PVC or silicone catheters can be in place or up to 3 months. T e urine collection container must be kept below the level o the bladder; back f ow o urine into the bladder can lead to in ection. When transporting or trans erring the catheterized patient, care must be taken that the catheter does not become entangled or dislodged.

al l eRgic React iOns Medical Equipment That Could Contain Latex

• • • • • • • • • • • • •

Disposable gloves Tourniquets Blood pressure cu s Stethoscopes Intravenous tubing Oral and nasal airways Enema tips Endotracheal tubes Syringes Electrode pads Catheters Wound drains Injection ports

Types o Reactions to Latex

• •

Irritant contact dermatitis

•

Latex allergy (immediate hypersensitivity)

Allergic contact dermatitis (delayed hypersensitivity)

Side Ef ect Versus Toxic Ef ect Medications are administered to meet speci c patient needs; medications can have harmless side e ects in some individuals. I the side e ect o sets the bene t, the medication might be discontinued. Medications can also have a toxic e ect. oxic e ects can occur because o sensitivity, overdose, or poor metabolism. An antidote is used to treat a toxic e ect. An allergy is an abnormal, acquired immune response to a substance (i.e., allergen) that would not usually trigger a reaction. An initial exposure to the allergen (i.e., sensitization) is required. Subsequent contact with the allergen then results in an in ammatory response. Examples o such responses include hay ever, urticaria, allergic rhinitis, eczema, and bronchial asthma. Allergens can be introduced into the body via contact, ingestion (e.g., ood), inhalation (e.g., dust, pollen), or injection (e.g., medication, drugs). Allergic reactions o particular importance to the radiographer involve the use o latex products and contrast media.

Latex Latex products are manu actured rom a milky f uid derived rom the rubber tree and several chemicals are added to the f uid during the manu acture o commercial latex. Some proteins in latex can produce mild-to-severe allergic reactions. In addition, chemicals added during processing can also cause skin rashes. When powdered latex gloves are worn, more latex proteins reach the skin. Also, when 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 allergy-producing proteins present. A wide variety o products contain latex: medical supplies, personal protective equipment, and many household items. T e intermittent use o latex products generally causes no health problems. However, workers in the healthcare industry (physicians, technologists, nurses, dentists, etc.) are at risk or developing latex allergy because they use latex gloves requently. Also at risk are other workers with requent glove use (hairdressers, housekeepers, ood service workers, etc.) and those involved in the manu acture o latex products. Irritant Contact Dermatitis. T e most common reaction to latex products is irritant contact dermatitis. It is characterized by the development o irritated dry, itchy areas on the skin, usually the hands. Irritant contact dermatitis is a skin irritation resulting rom the use o gloves and/ or rom exposure to other workplace products and chemicals. Irritant

Ch a Pt e r 4 Pa t Ie n t Mo n It o r In G, Me d ICa L e Me r Ge n CIe S, a n d Ph a r Ma Co Lo GY

contact dermatitis can also be caused by repeated hand washing, incomplete drying, use o sanitizers, and exposure to glove powder. Irritant contact dermatitis is not de ned as a true allergy. Allergic Contact Dermatitis. Allergic contact dermatitis (delayed hypersensitivity) results rom exposure to the chemicals added to latex during its manu acture. T ese chemicals can cause skin reactions like those produced by poison ivy, that is, the rash usually begins 24 to 48 hours ollowing contact and can lead to oozing skin blisters and/or spread to areas away rom the area o initial contact. Wearing latex gloves during episodes o hand dermatitis may increase skin exposure and the risk o developing latex allergy. Latex Allergy. Latex allergy (immediate hypersensitivity) can be a much more serious reaction to latex. Certain proteins in latex can cause sensitization and, although the amount o exposure needed to cause this sensitization is unknown, even very low-level exposure can trigger allergic reaction in some sensitized individuals. Reactions usually begin within minutes o exposure to the latex, but can occur hours later. Mild reactions involve skin redness, hives, or itching. More severe are respiratory reactions, or example, itchy eyes, runny nose, sneezing, di culty breathing, and wheezing. A li e-threatening reaction such as shock is rarely the rst sign o latex allergy. Such reactions are similar to those seen in some allergic persons a er a bee sting. Healthcare pro essionals should help educate latex-sensitized persons about the latex content o common objects.

Summary • Obtaining vital signs involves the measurement o body temperature, pulse rate, respiratory rate, and arterial blood pressure. • T e pulse represents regular expansion and contraction o an artery as waves o blood travel through it; the average normal adult pulse rate is between 60 and 100 beats/min. • T e ve most easily palpated pulse points are the radial, carotid, temporal, emoral, and popliteal pulse. • Normal adult oral body temperature is 98.6°F (37°C); rectal is generally 0.5°F to 1.0°F higher, axillary is usually 0.5°F to 1.0°F lower; in ants and children have a wider range o temperature; the elderly have lower body temperatures. • Normal adult systolic pressure ranges between 100 and 140 mm Hg; the normal diastolic range is between 60 and 90 mm Hg; blood pressure consistently more than 140/90 is considered hypertension. • T e normal respiratory rate is 12 to 18 breaths/min; young children is up to 30 breaths/min higher. • Symptoms o inadequate oxygen supply include dyspnea, cyanosis, diaphoresis, and neck vein distention; seated and semi-Fowler positions are help ul or dyspneic patients. • Oxygen is usually available through wall outlets with adjustable f owmeters, or in tanks having a f ow-regulation valve and an indicator showing the quantity o oxygen le in the tank.

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• Oxygen can be administered via nasal cannula, masks, or mechanical ventilators; oxygen supports combustion so it must be used away rom f ame. • Suction devices are used to aspirate secretions; suction is available rom wall outlets or portable suction mechanisms. • Needle size is indicated by gauge; larger gauge is equal to smaller needle bore. • Butterf y sets or IV catheters are generally used or IV injection o a contrast medium; the antecubital vein is generally used or injection o contrast material. • A heparin lock makes a vein accessible or medications administered at requent intervals. • IV solutions should be elevated 18 to 24 inch above the injection site. • Extravasation re ers to a leakage o medication or contrast medium rom a vein rupture or inadvertent introduction into tissue outside the vein. In ltration re ers to di usion o injected material into adjacent tissues. reatment includes removing the needle, applying pressure to prevent hematoma ormation, and a cold pack applied to relieve pain and limit urther in ltration. • Chest tubes unction to remove f uids or air rom the thoracic cavity. • NG and NI/NE tubes assist in the removal o gastric secretions or air and/or are used or the administration o water-soluble contrast material. • Urinary collection containers must be kept below the level o the bladder; to prevent U Is, catheterization procedures must be sterile. • An allergy is an abnormal, acquired immune response. • Allergens can be introduced into the body via contact, ingestion, inhalation, or injection. • Initial sensitization to the allergen is required; subsequent contact results in an in ammatory response. • Proteins in latex can produce mild-to-severe allergic reactions; types o reactions to latex include irritant contact and delayed or immediate hypersensitivity.

cOnt Rast Media Terminology and Basic Concepts Pa tient History. It is important that the radiographer obtain a short but adequate, patient history including reason(s) the examination has been requested. T is history should be obtained in a manner and environment that ensures patient privacy. Because patients are rarely examined or interviewed by the radiologist, observations, and in ormation obtained by the radiographer can be a signi cant help in making an accurate diagnosis.

Ch a Pt e r 4 Pa t Ie n t Mo n It o r In G, Me d ICa L e Me r Ge n CIe S, a n d Ph a r Ma Co Lo GY

In cases requiring documented in ormed consent, the radiographer will take special care to be certain that any unanswered patient questions are addressed and that the required documentation is veri ed and in place. Routes of Administration. Although radiographic contrast media are usually administered orally or intravenously, there are a number o routes and methods o drug administration. Drugs and medications may be administered either orally or parenterally. Parenteral re ers to any route other than via the digestive tract and includes topical (i.e., applied to the sur ace), subcutaneous (i.e., beneath the skin), intradermal (i.e., within the dermis/skin), intramuscular (i.e., within a muscle), intravenous (i.e., within a vein), and intrathecal (i.e., within the spinal canal). Purpose. T e purpose o a contrast medium is to arti cially increase subject contrast in body tissues and areas where there is little natural subject contrast. T e abdominal viscera, or example, have very little subject contrast; that is, it is very di cult to identi y speci c organs or distinguish one organ rom another. However, i a contrast agent is introduced into a particular organ such as the kidney or stomach, or into a vessel such as the aorta or one o its branches, we may more readily visualize these anatomic structures and/or evaluate physiologic activity. Types and Properties of Agents. Contrast media or contrast agents can be described as either positive (radiopaque) or negative (radiolucent). Positive, or radiopaque, contrast agents have a higher atomic number than the surrounding so tissue, resulting in a greater attenuation or absorption o x-ray photons. T ey, there ore, produce higher radiographic contrast. Examples o positive contrast media are iodinated agents (both water based and oil based) and barium sul ate suspensions. T e inert characteristics o barium sul ate render it the least toxic contrast medium. On the other hand, iodinated contrast media have characteristics that increase their likelihood o producing side e ects and reactions. Negative, or radiolucent, contrast agents used are air and various gases. Because the atomic number o air is also quite di erent rom that o so tissue, high subject contrast is produced. Carbon dioxide is absorbed more rapidly by the body than air. Negative contrast is o en used with positive contrast in examinations termed double-contrast studies. T e unction o the positive agent is usually to coat the various parts under study, while the air lls the space and permits visualization through the gaseous medium. Examinations that requently use double-contrast technique are barium enema (BE), upper GI (UGI) series, and arthrography.

Scheduling and Preparation Considerations Multiple Examinations. When patients are scheduled or multiple x-ray examinations, each requiring the use o a contrast medium, the examinations must be scheduled in the correct sequence. For example, i a particular patient must be scheduled or a UGI series, BE, and intravenous urogram (IVU), what sequence will permit optimal visualization o the required structures? Remember that it is important that residual barium does not overlie structures o interest. IVUs and radiographic examinations o the gallbladder (GB) are rarely requested today—having

Methods o Administration Oral

•

PO (by mouth), through digestive system

Parenteral

• • • • • •

Topical Subcutaneous Intradermal Intramuscular Intravenous Intrathecal

Contrast Media Positive (radiopaque)

• •

Barium sulfate Iodinated

Negative (radiolucent)

• •

Air Other gases

Sequencing and Combining Contrast Examinations Sequence *IVU *GB BE GI *GB and IVU examinations are rarely per ormed today, having been supplanted by other imaging methods.

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been supplanted by other imaging methods—but should either examination be requested, the accompanying table indicates when the examination would be scheduled among the others. Generally speaking, the examinations with a contrast medium that is excreted quickly and completely should be scheduled rst. T ere ore, i an IVU and GB had been requested, the IVU should be scheduled rst, ollowed by the GB. I the UGI series were scheduled next, residual barium would be in the large bowel the next day, thus preventing adequate visualization o the large intestine. T ere ore, the BE should be scheduled third; any residual barium is unlikely to inter ere with the UGI examination, although a preliminary scout image should rst be taken in each case.

Patient Preparation GB Iodinated contrast evening before examination; water only in AM UGI NPO after midnight BE Cathartics, cleansing enemas IVU NPO after midnight, cleansing enemas, empty bladder before scout lm

Patient Preparation. 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. A patient scheduled or a UGI series must be NPO (nothing by mouth) a er midnight. A BE (lower GI) 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. Af ercare or BE is very important. Patients are typically instructed to take milk o magnesia, increase their intake o ber, drink plenty o water, to expect change 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.

Contraindications and Patient Education

Qualities o Iodinated Contrast Agents That Contribute to Discom ort, Side Ef ects, and Reactions Viscosity. More viscid (thick, sticky) agents are more di cult to inject and produce more heat and vessel irritation; the higher the concentration, the greater the viscosity; viscosity also increases as room temperature decreases. Toxicity. Potential toxicity is greater with higher concentration agents and ionic agents. Miscibility. Contrast agents should be readily miscible (able to mix) with blood. Osmolality. Low-osmolality agents have fewer particles in a given amount of solution and are less likely to provoke an allergic reaction.

Radiopaque contrast media are most requently employed or radiographic procedures. Barium sul ate is one type o radiopaque contrast agent that is used to visualize the GI tract. Mixed with water, it orms a suspension that is usually administered orally or demonstration o the UGI tract (esophagus, stomach, and progression through the small intestine), and rectally or demonstration o the lower GI tract (large intestine). Barium sul ate is contraindicated i a per oration is suspected somewhere along the course o the GI tract (e.g., a per orated diverticulum or gastric ulcer). Escape o barium sul ate into the peritoneal cavity can result in peritonitis. In these cases, a water-soluble, absorbable, iodinated contrast medium is generally used instead o barium. T e water-soluble preparations are available as ready-mixed liquid or as powder requiring appropriate dilution with water. A patient with an NG tube can have the contrast medium administered through it or the purpose o locating and studying any site o obstruction. T is procedure is called enteroclysis. Barium preparations in the large bowel become thickened as a result o absorption o their f uid content, a process called inspissation, causing symptoms rom mild constipation to bowel obstruction. Constipation

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can be a serious problem, particularly in the elderly, and ecal impaction or obstruction can result. It is essential that the radiographer provide clear instructions or ollow-up a ercare, especially to outpatients. Patients are usually advised to expect light-colored stools or the next ew days, to drink plenty o f uids, to increase their intake o ber, and to take a mild laxative such as milk o magnesia ollowing a barium study. Iodinated contrast agents are another type o radiopaque contrast medium. T ey may be oil based or water based. Oil-based contrast media are rarely used today, having been replaced by water-soluble iodinated contrast media. Oil-based contrast media are not water soluble, not readily absorbed by the body, and remain in body tissues or lengthy periods o time. Examinations that ormerly employed the use o oil-based contrast agents are myelograms, lymphangiograms, sialograms, and bronchograms. Water-based contrast media are either ionic or nonionic. T ese agents are principally used to delineate the urinary and vascular systems, and the GI tract when barium sul ate is contraindicated. Ionic contrast media have a higher osmolality, that is, a greater number o particles in a given amount o solution. Nonionic, or low osmolality, contrast agents are used especially with children, the elderly, patients with renal disease, patients having a history o allergic reaction to contrast media, or patients having multiple allergies. Side e ects and allergic reactions are less likely and less severe with these media. Nonionic contrast agents are associated with less injection discom ort, and a lower incidence o nausea, vomiting, and cardiovascular complications. T eir only disadvantage is their cost, which is ar greater than that o ionic contrast agents. Iodinated contrast agents can become more viscous at normal room temperature, making injection more di cult. Warming the contrast to body temperature, in a special warming oven, reduces viscosity, permitting an easier and more com ortable injection. Diabetic patients taking insulin who are scheduled or a UGI series are generally instructed to withhold their morning insulin but to bring their insulin with them to take a er the examination. Should the diabetic patient take insulin be ore the examination and remain NPO or a length o time, a reaction might occur, especially i the examinations were delayed or any reason. UGI examinations on diabetic patients should be among the rst examinations scheduled each day and priority should be given to these patients.

Pharmacology, Reactions, and Emergency Situations Anaphylaxis is a li e-threatening allergic reaction that a ects millions o Americans every year and can be caused by a variety o allergens. Anaphylaxis can result rom the body’s sensitivity and allergic reaction to certain oods, insect venom, medications, anesthetics, and latex. T e reaction can be the result o ingestion, injection, or absorption o the sensitizing agent. Because iodinated contrast media are potentially toxic, the radiographer must be knowledgeable and alert to the possible adverse e ects o their use (although the risk o a li e-threatening reaction is relatively rare). Reactions to contrast media generally occur within 2 to 10 minutes ollowing injection and can a ect all body systems.

Reactions Can Result From

• • •

Ingestion, Injection, or Absorption . . . of the sensitizing agent

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T e body’s response to the introduction o contrast material is the production o histamines, which brings about various symptoms. Symptoms o a mild systemic reaction include a f ushed appearance, nausea, a metallic taste in the mouth, nasal congestion, a ew hives (urticaria), and, occasionally, vomiting. reatment o these minor symptoms generally consists o administration o either an antihistamine such as diphenhydramine (Benadryl), which blocks the action o the histamine and reduces the body’s inf ammatory response or an epinephrine to raise the blood pressure and relax the bronchioles (see able 4–1).

tabl e 4–1. Common Medications and Their Applications Type

Ef ect

Example

Adrenergic

Vasopressor, stimulates sympathetic nervous system: increases BP, relaxes smooth muscle of respiratory system

Epinephrine (Adrenalin)

Analgesic

Relieves pain

Aspirin, acetaminophen (Tylenol), codeine, meperidine (Demerol)

Antiarrhythmic

Relieves cardiac arrhythmia

Quinidine sulfate, lidocaine (Xylocaine)

Antibacterial

Stops growth of bacteria

Penicillin, tetracycline, erythromycin

Anticholinergic

Depresses parasympathetic system

Atropine, scopolamine, belladonna

Anticoagulant

Inhibits blood clotting; keeps IV lines and catheters free of clots

Heparin, warfarin

Anticonvulsant

Prevents/relieves convulsions

• •

Antidepressant

Prevents/alleviates mental depression

• • • •

Carbamazepine (Tegretol) Phenytoin (Dilantin) Fluoxetine (Prozac) Paroxetine (Paxil) Sertraline (Zoloft) Nortriptyline (Pamelor, Aventyl)

Antihistamine

Relieves allergic symptoms

Diphenhydramine hydrochloride (Benadryl)

Antipyretic

Reduces fever

Aspirin, acetaminophen

Antitussive

Reduces coughing

Dextromethorphan (Romilar)

Barbiturate

Depresses CNS, decreases BP and respiration, and induces sleep

Phenobarbital sodium (Nembutal), secobarbital sodium (Seconal)

Cardiac stimulant

Increases cardiac output

Digitalis

Cathartic

Laxative, relieves constipation, prepares colon for diagnostic tests

Bisacodyl (Dulcolax), castor oil

Diuretic

Stimulates urine

Furosemide (Lasix)

Emetic

Stimulates vomiting

Activated charcoal; Ipecac

Hypoglycemic

Lowers blood glucose

Insulin, chlorpropamide (Diabinese), metformin (Glucophage)

Narcotic (opioid)

Sedative/analgesic; potentially addictive

Morphine, codeine, meperidine (Demerol)

NSAID

Nonsteroidal pain relief

• • •

Aspirin (Bayer, and others) Ibuprofen (Motrin, and others) Naproxen (Aleve, and others)

Stimulant

Stimulates the CNS

Ca eine, amphetamines

Tranquilizer

Reduces anxiety

Diazepam (Valium); alprazolam (Xanex)

Vasodilator

Relaxes and dilates blood vessels, decreases BP

Nitroglycerine, verapamil

Ch a Pt e r 4 Pa t Ie n t Mo n It o r In G, Me d ICa L e Me r Ge n CIe S, a n d Ph a r Ma Co Lo GY

Potentially li e-threatening (anaphylactic) systemic responses include respiratory ailure, shock, and death within minutes. Early symptoms o an anaphylactic reaction include itching o the palms and soles, wheezing, constriction o the throat (possibly caused by laryngeal edema), dyspnea, dysphagia, hypotension, and cardiopulmonary arrest. T e radiographer must maintain the patient’s airway, summon the radiologist, and call a “code.” T e radiographer should then be prepared to stay with the patient and assist until the arrival o the code team. T e diabetic patient requires a di erent sort o attention. 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 met ormin. T e manu acturer recommends that patients taking metormin 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]). T e ACR recommends that patients on Met ormin be classi ed into one o three categories, each having somewhat di erent suggested management. T ese recommendations can be ound at http://www.acr.org/~/media/ACR/Documents/PDF/Quality Sa ety/Resources/Contrast%20Manual/2013_Contrast_Media.pd

Summary • Drugs and medications may be administered orally or parenterally. • Parenteral administration includes topical, oral, subcutaneous, intradermal, IM, IV, and intrathecal. • Multiple radiologic examinations must be scheduled in a sequence that will allow prompt and adequate visualization o structures o interest. • Patients must be appropriately prepared or the contrast examination(s) or which they are scheduled. • Arti cial contrast media unction to increase insu cient subject contrast; arti cial contrast media can be positive (radiopaque) or negative (radiolucent). • Positive contrast media include barium sul ate and iodinated (oil- or water-based) agents; negative and positive contrast agents are o en used together in “double-contrast” studies. • Qualities o iodinated contrast media that contribute to their risk include viscosity, toxicity, and miscibility. • Water-soluble (absorbable) contrast agents are used in place o barium sul ate when visceral per oration is suspected. • Patients require clear and complete postprocedural instructions, particularly ollowing barium examinations. • Nonionic iodinated contrast agents produce ar ewer side e ects than do their ionic counterparts; nonionic contrast agents are more expensive. • Reactions to ionic agents usually occur within 2 to 10 minutes ollowing injection.

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• Symptoms o a mild reaction include mild urticaria, f ushing, nausea, nasal congestion, metallic taste; an antihistamine is usually given to the patient. • o avoid renal dys unction, diabetic patients taking met ormin must discontinue its use or 48 hours a er the administration o an intravascular contrast agent.

Ot heRMedical eMeRgencies T e importance o radiographers’ care ul evaluation o their patients is never more obvious than when an emergency arises. An emergency is de ned as a sudden change in a patient’s condition requiring immediate medical intervention. Most patients arrive in the radiology department in a stable condition; a ew arrive or diagnostic evaluation o a medical crisis. T e radiographer must note the patient’s condition on arrival and be alert to any subsequent sudden change in that condition. T e value o continual review o the knowledge and skills required or emergency situations cannot be overemphasized. Many o these emergencies can occur with little or no warning. Many can be li e threatening i not dealt with immediately and correctly.

Vomiting Vomiting patients who are seated or standing should be provided with a basin, tissues, and water or rinsing their mouths. It is essential that recumbent patients have their heads turned to the side to prevent choking rom aspiration o vomitus. Patients who report eeling nauseous are o en apprehensive and may get some relie by breathing slowly and deeply through their mouths.

Fractures An unsplinted racture must be moved with great care, with areas proximal and distal to the racture site adequately supported. Any motion is very pain ul and can result in urther injury to tissues surrounding the racture. Muscle spasm can cause additional pain and can inter ere with proper reduction o the racture. A splint should never be removed rom an extremity except by or under the direct supervision o the physician. Some splinting devices are not radiolucent and removal may be required be ore the radiographic examination. Rib ractures may be associated with lung trauma and sternum ractures with heart lacerations. Rib ractures can be very pain ul—the patient experiences pain just rom breathing. Pelvic ractures are o en associated with injuries to pelvic and abdominal viscera, and extreme care must be taken to avoid hemorrhage.

Spinal Injuries Patients arriving or radiographic evaluation with possible spinal injuries must not be moved. T e position o any sandbags or other supportive mechanisms must not be changed. A horizontal (cross-table) lateral

Ch a Pt e r 4 Pa t Ie n t Mo n It o r In G, Me d ICa L e Me r Ge n CIe S, a n d Ph a r Ma Co Lo GY

projection should be evaluated by the physician rst to determine the extent o injury and necessity or urther radiographs. I the patient must be placed in a lateral position, the logrolling method is usually advised. A physician must be present whenever the patient’s position is changed.

Epistaxis A nosebleed (epistaxis) may be a result o any one o many causes, including hypertension, dry nasal mucous membranes, sinusitis, or trauma. T e patient should be seated or in a Fowler position. T e radiographer should place cold cloths over the patient’s nose and back o the neck. Compressing the sides o the nose against the nasal septum or 6 to 8 minutes is also help ul. Continued hemorrhage should be brought to the attention o the physician because cautery or nasal packs might be required.

Postural Hypotension Orthostatic, or postural, hypotension is a decrease in blood pressure that occurs on rising to the erect position. It can be severe enough to cause ainting in individuals who have been con ned to bed or several days. T e radiographer should assist patients slowly and be watch ul or signs o weakness.

Vertigo Objective vertigo is the sensation o having objects (or “the room”) spinning about the person; subjective vertigo is the sensation o the person spinning about. It is usually associated with an inner-ear disturbance. Patients experiencing true vertigo (as opposed to dizziness or lightheadedness) are o en very nauseous and must be protected rom alls with the use o side rails and/or sa ety belts.

Syncope A patient who reports eeling dizzy or aint should be immediately assisted to a chair. Bending orward and placing the head between the knees will o en help relieve the lightheadedness as blood f ow to the brain increases. In more severe cases, a patient who cannot be assisted to a chair should be lowered to a recumbent position. Elevation o the lower legs or use o the rendelenburg position is help ul. I the patient loses consciousness, the radiographer should make certain that the airway is open and that clothing, especially at the collar, is loose. Once the patient is recumbent, recovery is usually swi ; however, a physician should be noti ed and the cause o syncope identi ed.

Convulsion Involuntary muscular contractions and relaxations, o en associated with epilepsy or other neurologic disorder, characterize a convulsion. Febrile convulsions are associated with ever, especially in children. During convulsion, no attempt must be made to restrain the patient’s

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movements. T e radiographer’s responsibility is to keep patients rom injuring themselves. ight clothing can be loosened and objects that could harm the patient should be moved out o the way. T e use o a padded tongue blade is no longer usually recommended; it can induce emesis or cause tooth breakage. Most convulsions are o short duration and sel -limited. Medical intervention is o en unnecessary; it is most important that the patient be protected rom injury rom objects lying close by. T e term seizure is o en used interchangeably with the term convulsion. However, there are many di erent types o seizures. Some seizures have very mild symptoms with little or none o the body movement that characterizes the convulsion.

Seizure T e type o seizure known as petit mal is so subtle as to go unnoticed by the patient and observer. It is characterized by brie loss o consciousness (10–30 seconds) and accompanied by eye or muscle f uttering. A grand mal seizure is characterized by loss o consciousness and alling, ollowed by generalized muscle spasms. T e radiographer should remove any objects in the area that could harm the patient and loosen any tight clothing. T e patient’s head should be turned to the side to allow any secretions to f ow rom the mouth. A padded tongue blade should be placed between the patient’s teeth to help avoid biting the tongue.

Unconsciousness Unconsciousness is the state o being partially or completely unaware o external stimuli. T is state occurs during normal sleep, and can also occur in illness and trauma. Pathologic unconsciousness can be caused by a wide variety o conditions including insulin overdose, ainting, uremia, concussion, heat stroke, and intoxication. It is important to remember, as we image the unconscious patient, that the sense o hearing is believed to be the last sense that one loses. Imagine how com orting it can be to the unconscious patient to hear their caregiver(s) talking to them and explaining what is going on around them. T ere are various levels o consciousness and the condition o an acutely ill patient can rapidly deteriorate rom being ully aware and responsive to diminished or inappropriate responsiveness, to complete unresponsiveness. T e unconscious patient must never be le unattended. T e radiographer must be alert to changes in the patient’s level o consciousness and noti y the physician immediately o any deterioration.

Acute Abdomen Patients arriving or radiographic evaluation having a diagnosis o “acute abdomen” are usually su ering severe abdominal pain, are nauseous and vomiting, and are requently close to being in shock. T ese are indeed very sick patients. T e radiographer must per orm the examination swi ly and e ciently and remain alert or any sudden changes in patient condition.

Ch a Pt e r 4 Pa t Ie n t Mo n It o r In G, Me d ICa L e Me r Ge n CIe S, a n d Ph a r Ma Co Lo GY

Shock Shock is a general term and is characterized by diminished peripheral blood f ow and insu cient oxygen supply to body tissues. Shock can be caused by a number o conditions including allergic reaction, trauma, hemorrhage, myocardial in arction, and in ection. T e patient is pale and may become cyanotic; the pulse is rapid and weak, breathing is shallow and rapid, and blood pressure drops sharply. T e radiographer should keep the patient warm and f at, or in the rendelenburg position, and be prepared to assist with emergency procedures.

Respiratory Failure T e inability o the lungs to per orm ventilating unctions is respiratory distress and may be described as acute or chronic. Acute respiratory distress can be caused by impaired gas exchange processes (requiring positive-pressure ventilation) or airway obstruction (requiring the Heimlich maneuver). Chronic respiratory ailure is a result o a disease process that impairs breathing, such as emphysema, bronchitis, asthma, or cystic brosis. T e radiographer should be able to distinguish between respiratory arrest (absence o chest movement and breathing sounds) and cardiopulmonary arrest (absence o pulse and respiration with loss o consciousness) and be able to initiate li e-saving actions.

Cardiopulmonary Arrest 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. 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. Many healthcare acilities require their employees to be certi ed in basic li e-saving skills. It is wise or radiographers (and the general public) to be amiliar with skills such as the Heimlich maneuver (abdominal thrust) and cardiopulmonary resuscitation should the need arise.

Stroke A stroke, or cerebrovascular accident (CVA), is an inter erence with blood supplied to the brain as a result o occlusion or rupture o a cerebral vessel. I the condition results rom a partial vessel occlusion, the inter erence is usually mild and temporary and is re erred to as a transient ischemic attack ( IA). T e patient may experience temporary blindness in one eye, dysphasia or aphasia, hemiparesis or hemiplegia, or anesthesia. I the cerebral vessel is totally occluded or ruptures into the brain or subarachnoid space, a much more serious event has occurred. T e

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patient requently experiences sudden loss o consciousness and onesided paralysis (hemiparesis), although the onset can be slower i the occlusion is caused by thrombus ormation. Other symptoms include speech disturbances and cool, sweaty skin. Patients should have their head and shoulders elevated or be in the lateral recumbent position; an open airway must be maintained. Because a stroke can occur without warning at any time, the radiographer should be amiliar with the signs o an impending stroke and be able to provide appropriate immediate care.

Summary • It is essential that the radiographer be alert or any sudden changes in patient condition; how well the radiographer recognizes and is prepared to meet the challenges o emergency situations can largely determine the outcome o the emergency.

Ch a Pt e r 4 Pa t Ie n t Mo n It o r In G, Me d ICa L e Me r Ge n CIe S, a n d Ph a r Ma Co Lo GY

cOMPReh en s iOn ch eck Congratulations! You have completed your review of this chapter. If you are able to answer the following group of comprehensive questions, you can feel con dent that you have mastered this section. You are then ready to go on to “Registry-type” questions that follow. For greatest success, do not go to these multiple-choice questions without rst completing the short-answer questions below. 1. Discuss the importance of careful and accurate patient assessment; what are the components of a good assessment (p. 47)? 2. List the four vital signs, identify their adult norms, and list/identify equipment necessary for their assessment (p. 48).

17. Explain the function of chest tubes and precautions that should be taken by the radiographer (p. 54). 18. Describe the function of NG and NI tubes and any precautions that should be taken by the radiographer (p. 55). 19. Identify the classi cation and purpose of the PICC, Hickman, and Port-A-Cath lines (p. 55). 20. Describe the function of urinary catheters and any precautions that should be taken by the radiographer (p. 55, 56). 21. Identify the level at which urinary collection containers should be kept (p. 56). 22. De ne allergy; discuss sensitization and in ammatory response (p. 56).

3. What does the pulse that we feel actually represent? What are some variables that can a ect pulse rate? List common pulse points (p. 48, 49)?

23. Distinguish between side e ect and toxic e ect (p. 56).

4. De ne the terms diaphoretic, cyanotic, ebrile, hypertension, systole, bradycardia, and hypoxia (p. 49, 50).

24. List the three types of latex reactions; discuss the e ect powder can have in latex gloves (p. 56, 57).

5. Identify illnesses/conditions that might require supplemental oxygen (p. 50, 51).

25. Discuss the di erence between delayed and immediate hypersensitivity (p. 56, 57).

6. What condition speci cally requires a low ow rate of oxygen (p. 51)?

26. Discuss the importance of observing initial patient condition and any subsequent changes (p. 58).

7. List the subjective symptoms of inadequate oxygen; identify the body position frequently helpful for the dyspneic patient (p. 51).

27. Describe the di erence between oral and parenteral drug administration; list ve types of parenteral administration (p. 59).

8. Describe four methods of oxygen therapy and identify when each might be indicated (p. 51, 52).

28. Explain the purpose of arti cial contrast media (p. 59).

9. Identify any hazards involved in the use of oxygen (p. 51).

29. Identify the two types of contrast media, describe their characteristics, and give examples of each (p. 59).

10. Describe the circumstance(s) in which suction might be required; identify types of suction devices available (p. 51, 52). 11. Identify how needle bore changes with increasing/ decreasing gauge (p. 52). 12. Describe the function and uses of a heparin lock (p. 52). 13. Identify the correct needle angle for subcutaneous, intravenous, and intramuscular injections (p. 54). 14. Identify the height at which IVcontainers should be hung (52). 15. Explain how contrast medium extravasation/in ltration should be treated (p. 53). 16. Identify the vein(s) frequently used for introduction of contrast medium (p. 53).

30. Explain the appropriate patient preparation for UGI, BE, and IVU (p. 59, 60). 31. Explain why a diabetic patient who is required to receive nothing by mouth beginning the preceding midnight should be scheduled as the rst am appointment (p. 61). 32. Describe the risks associated with iodinated contrast media and identify the type of iodinated media associated with less risk (p. 61, 63). 33. Describe three qualities of iodinated contrast media that contribute to the production of side e ects (p. 60). 34. Explain how double-contrast examinations can serve to better demonstrate certain anatomic parts (p. 59).

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35. Describe contraindications to the use of barium sulfate; identify the alternative contrast medium (p. 59). 36. Explain the importance of a tercare explanations, especially following barium examinations (p. 60). 37. Distinguish between oil- and water-based iodinated contrast media, their uses, and their characteristics (p. 61). 38. Identify the basic di erence between ionic and nonionic contrast media and identify when use of nonionic agents is indicated (p. 61). 39. Describe symptoms a patient having a mild reaction to iodinated contrast media might experience and their usual treatment (p. 62). 40. Describe the symptoms of a possible impending anaphylactic reaction and the radiographer's responsibilities (p. 63). 41. Describe care provided to the nauseous or vomiting patient; identify the body position required for the recumbent patient (p. 64). 42. Describe precautions the radiographer should take when examining a patient with a fracture (p. 64).

43. Discuss precautions that should be taken with patients having suspected spinal injuries (p. 64, 65). 44. Describe rst aid for epistaxis (p. 65). 45. Distinguish between postural hypotension, vertigo, and syncope; discuss precautions taken and care given by the radiographer (p. 65). 46. Discuss any unique considerations that should be addressed when caring for the unconscious patient (p. 66). 47. Describe symptoms of acute abdomen and shock; indicate any precautions that should be taken by the radiographer (p. 66, 67). 48. Discuss the di erence between convulsion and seizure. Distinguish between grand mal and petit mal seizures; discuss the care appropriate for a patient experiencing a grand mal seizure (p. 65, 66). 49. Distinguish between respiratory arrest and cardiopulmonary arrest; discuss the responses appropriate to the radiographer (p. 67). 50. Describe “stroke,” to include some symptoms and responses appropriate for the radiographer (p. 67, 68). 51. List/name the three parts of a chest drainage system (p. 54, 55).

Ch a Pt e r 4 Pa t Ie n t Mo n It o r In G, Me d ICa L e Me r Ge n CIe S, a n d Ph a r Ma Co Lo GY

ch a Pt eR Review q u es t iOn s 1. Which of the following is/are symptom(s) of inadequate oxygen supply?

6. Parenteral administration of drugs may be performed:

1. Diaphoresis

1. Intrathecally

2. Cyanosis

2. Intravenously

3. Dyspnea

3. Orally

(A) 1 only

(A) 1 only

(B) 1 and 2 only

(B) 1 and 2 only

(C) 2 and 3 only

(C) 3 only

(D) 1, 2, and 3

(D) 1, 2, and 3

2. A patient’s feeling of spinning, or the room spinning about him, is called:

7. What is the most frequently used site for intravenous injection of contrast agents?

(A) Orthostatic hypotension

(A) Basilic vein

(B) Epistaxis

(B) Cephalic vein

(C) Vertigo

(C) Antecubital vein

(D) Syncope

(D) Femoral vein

3. Example(s) of negative contrast agents include:

8. Types of NG/NI/NE tubes include:

1. Air

1. Port-A-Cath

2. Iodine

2. Sengstaken–Blakemore

3. Barium sulfate

3. Miller–Abbott

(A) 1 only

(A) 1 only

(B) 1 and 2 only

(B) 1 and 2 only

(C) 2 and 3 only

(C) 2 and 3 only

(D) 1, 2, and 3

(D) 1, 2, and 3

4. Which of the following gauge needles has the smallest bore?

9. A patient’s IV container should be hung: (A) 18 to 24 inch above the vein

(A) 12

(B) 18 to 24 inch below the vein

(B) 18

(C) 18 to 24 inch above the heart

(C) 20

(D) 18 to 24 inch below the heart

(D) 23

10. The usual patient preparation for a UGI examination is:

5. What should be the angle formed between the needle and skin surface for an intravenous injection? (A) 15 degrees (B) 45 degrees

(A) NPO 8 hours before the examination (B) Light breakfast only the morning of the examination

(C) 60 degrees

(C) Clear uids only the morning of the examination

(D) 90 degrees

(D) Two ounces of castor oil and enemas until clear

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a

r

exp

o

1. (D) Symptoms of inadequate oxygen supply include dyspnea, cyanosis, diaphoresis, and distention of the veins of the neck. The patient who experiences some or all of these symptoms will be very anxious and must not be left unattended. The radiographer must call for help, assist the patient to a sitting or semi-Fowler position (the recumbent position makes breathing more di cult), and have oxygen and emergency drugs available.

an 18-gauge needle. Hypodermic needles are generally used for phlebotomy (i.e., blood samples), whereas butteries and IV catheters are used more frequently for injections such as contrast media. If an infusion injection is required, an IV catheter is generally preferred. The hub of the hypodermic needle is attached to a syringe, while the hub of the butter y tubing or IV catheter may be attached to a syringe or an IVcontainer via an IVinfusion set.

2. (C) Objective vertigo is the sensation of having objects (or “the room”) spinning about the person; subjective vertigo is the sensation of the person spinning about. It is often associated with an inner-ear disturbance. Patients experiencing true vertigo (as opposed to dizziness or lightheadedness) are often very nauseous and must be protected from falls. A patient who reports feeling dizzy or faint (syncope) should be immediately assisted to a chair. Bending forward and placing the head between the knees will often help relieve the lightheadedness as blood ow to the brain increases. In more severe cases, a patient who cannot be assisted to a chair should be lowered to a recumbent position. Elevation of the lower legs, or use of the Trendelenburg position, is helpful. Orthostatic, or postural, hypotension is a decrease in blood pressure that occurs on rising to the erect position. It can be severe enough to cause fainting in individuals who have been con ned to bed for several days. A nosebleed (epistaxis) may be a result of any one of many causes, including hypertension, dry nasal mucous membranes, sinusitis, or trauma. The patient should be seated or placed in a Fowler position. The radiographer should place cold cloths over the patient’s nose and back of the neck.

5. (A) The antecubital vein is the most commonly used venipuncture site for contrast medium administration. The basilic vein, located on the dorsal surface of the hand, is used when the antecubital vein is inaccessible. The cephalic vein may also be used (see Fig. 4–1). The needle is inserted into the vein at a 15-degree angle; blood will ow back into the tubing when the needle is correctly positioned. Strict aseptic technique must be used. The needle forms a 90-degree angle with the skin in intramuscular injections and a 45-degree angle in subcutaneous injections. 6. (B) Although radiographic contrast media are usually administered orally or intravenously, there are a number of routes or methods of drug administration. Drugs and medications may be administered either orally or parenterally. Parenteral refers to any route other than the digestive tract (orally) and includes topical, subcutaneous, intradermal, intramuscular, intravenous, and intrathecal.

3. (A) Negative, or radiolucent, contrast agents used are air and various gases. Because the atomic number of air is also quite di erent from that of soft tissue, high subject contrast is produced. Carbon dioxide is absorbed more rapidly by the body than air. Negative contrast is often used with positive contrast in examinations termed double-contrast studies. The function of the positive agent is usually to coat the various parts under study, while the air f lls the space and permits visualization through the gaseous medium. Examinations that frequently use double-contrast technique are BE, UGI series, and arthrography. 4. (D) The diameter of a needle is identi ed as its gauge. As the diameter of its bore decreases, the gauge increases. Hence, a 23-gauge needle has a smaller diameter bore than

7. (C) The antecubital vein is the most commonly used injection site for contrast medium administration. It is not used for infusions that take longer than 1 hour because of its location at the bend of the elbow. The basilic vein, located on the dorsal surface of the hand, is used when the antecubital vein is inaccessible. The cephalic vein may also be used. Strict aseptic technique must be used for all intravenous injections. 8. (C) Gastrointestinal (GI) tubes can be nasogastric (NG), nasointestinal (NI), or nasoenteric (NE). NG tubes, such as the Dobho tube, are used as feeding tubes for patients whose condition prevents normal swallowing. NI/NE tubes can be used following digestive tract surgery to remove gastric uids and/or air (decompression; e.g., Levin and Salem-Sump tubes). NG and NI/NE tubes may be single or double lumen and can sometimes be temporarily disconnected for radiographic examinations. The single-lumen NG or NI/NE tube can be clamped, but the double-lumen tube must never be clamped. If clamped, the walls of the double-lumen tube could adhere permanently. Instead, the tip of a syringe is inserted into the

Ch a Pt e r 4 Pa t Ie n t Mo n It o r In G, Me d ICa L e Me r Ge n CIe S, a n d Ph a r Ma Co Lo GY

lumen and the syringe and tube then pinned (open side up) to the patient’s gown. Care must be taken not to disturb the placement of the GI tube. Examples of singlelumen NE tubes are the Cantor and Harris tubes; the Miller–Abbott tube is a double-lumen NE tube. The Sengstaken–Blakemore tube is a triple-lumen tube having a gastric balloon, an esophageal balloon, and a gastric suction port; it is often used in the treatment of bleeding esophageal varices. 9. (A) The IV container should be hung 18 to 24 in above the level o the vein. If placed lower than the vein, solution will stop owing and blood will return into the tubing. If hung too high, solution can run too fast. Occasionally, the position of the needle or catheter in the vein will a ect the ow rate. If the bevel is adjacent to the vessel wall, ow may decrease or stop altogether. Often, just changing the position of the patient’s arm will remedy the situation. 10. (A) Patient preparation di ers for various contrast examinations. To obtain a diagnostic examination of the stomach, it must rst be empty. The usual UGI preparation

is NPO (nothing by mouth) after midnight (approximately 8 hours before the examination). Any material in the stomach can simulate the appearance of disease. An iodinated contrast agent, usually in the form of several pills, is taken by the patient the evening before a scheduled GB examination and only water is allowed the morning of the examination. The patient scheduled for a BE (lower GI) requires a large bowel that is very clean prior to the administration of barium; this requires the administration of cathartics (laxatives) and cleansing enemas. Preparation for an IVU requires that the patient be NPO after midnight; some institutions may require that the large bowel be cleansed of gas and fecal material. A tercare for barium examinations is also very important. Patients are typically instructed to take milk of magnesia and to drink plenty of water. Because water is removed from the barium sulfate suspension in the large bowel, it is essential to make patients understand the importance of these instructions to avoid barium impaction in the large bowel.

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PART

II

Imaging Procedures

CHAPTER 5 General Procedural Considerations Body Planes Body Habitus Sur ace Landmarks and Localization Points Skeletal Motion Terminology Preliminary Steps and Procedural Guidelines Immobilization and Respiration Modif ed and Additional Projections

CHAPTER 6 Imaging Procedures: Anatomy, Positioning, and Pathology

The Axial Skeleton Vertebral Column Thorax Head and Neck Body Systems Respiratory System Biliary System Digestive System Urinary System Female Reproductive System Central Nervous System Circulatory System

The Skeletal System The Appendicular Skeleton Upper Limb/Extremity and Shoulder Girdle Lower Limb/Extremity and Pelvis

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General Procedural Considerations

5

OBJECTIVES At the conclusion o this chapter, the student will be able to: • De ne anatomical/positioning terms. • Identi y the body planes. • Discuss various procedural modi cations the radiographer can employ in nonroutine/emergent circumstances. • Discuss how an understanding o patient body habitus and body sur ace landmarks impacts ease and accuracy o imaging procedures. • Explain the concepts and steps involved in per orming an accurate and e cient imaging procedure. T e development o positioning skills requires a thorough knowledge o normal anatomy, an awareness o pathologic conditions and their impact on positioning limitations, and selection o prudent technical actors. A review o basic positioning principles and terminology is essential to an overview o radiographic procedures. T ere ore, several tables and gures in this chapter summarize the undamental principles o imaging procedures: body planes (Fig. 5–1), body habitus (Figs. 5–2 and 5–3), our quadrants and nine regions o the abdomen (Fig. 5–4), body sur ace landmarks and localization points (Fig. 5–5), and standard terminology (Fig. 5–6). T e student should be thoroughly acquainted with these be ore approaching the study o speci c positioning skills. It must be emphasized that a patient’s condition o en impacts their ability to move readily on the x-ray table or maintain positions or lengthy periods o time. Most o the descriptions o positions o a part in Chapter 6 can be readily employed with patients not severely injured and patients without debilitating pathology; in many instances, suggested modi cations or traumatized patients are included. One measure o a skill ul radiographer is his or her ability to be cautious and resource ul when examining injured or debilitated patients having pathologic or traumatic conditions—such as arthritis, bone ractures,

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PART II IMAGING PRO CEDURES

Body Habitus: Types, Characteristics, and Prevalence Midcoronal plane

Midsagittal plane

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 (Fig. 5–3A) Colon/large bowel peripheral Gallbladder high and lateral

Transverse plane

Asthenic (10%)

• • • •

Body slender and light

•

Colon/large bowel low, medial, and redundant

•

Gallbladder low and medial

Bony ramework delicate Thorax long and narrow Stomach very low and long (“ sh hook”) (Fig. 5–3B)

Pos

te rio r

Sthenic and hyposthenic types characterize the more average body types:

An te r

Sthenic (50%)

• •

io r

Figure 5–1. Body planes.

Build average and athletic Similar to hypersthenic, but modi 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

Hype rs the nic

A

S the nic

B

Figure 5–2. (A–D) The position, shape, and motility o various organs can di er greatly rom one body habitus to another. Each o the body habitus types is shown and the characteristic variations in shape and position o the diaphragm, lungs, and stomach are illustrated. The radiographer must consider these characteristic di erences while per orming radiographic examinations on individuals o various body habitus.

CHAPTER 5 GENERAL PRO CEDURAL CO NSIDERATIO NS

Hypos the nic

C

As the nic

D

Figure 5–2. (Continued )

A

Figure 5–3. (A) Example o hypersthenic stomach. (B) Example o asthenic stomach. (Photo Contributor: Stam ord Hospital, Department o Radiology.)

B

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PART II IMAGING PRO CEDURES

Epiga s trium

RUQ

Right hypochondrium

LUQ

Le ft hypochondrium

Right lumba r

RLQ

Umbilica l

Right ilia c

LLQ

A

Hypoga s tric

Le ft lumba r

Le ft ilia c

B

Figure 5–4. (A) Four quadrants o the abdomen, illustrating position o major organs. (B) Nine regions o the abdomen, illustrating position o major organs.

A. EAM A B C1/ma s toid proce s s

C D

C5/thyroid ca rtila ge

E F G

T2–3/ s upra s te rna l notch

1 1 ⁄2 "

H

T4–5/s te rna l a ngle I T10/xiphoid proce s s J

L4/ilia c cre s t

K

S 1–2/AS IS

L

B. Ma s toid tip

1 2 3 4 5 6 7 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4

C. Gonion D. Thyroid ca rtila ge E. Top of s houlde rs F. G. S upra s te rna l notch H. S te rna l a ngle I. Midthora x J. Xiphoid tip

K. Lowe r cos ta l ma rgin L. Ilia c cre s t

5 Coccyx/ s ymphys is pubis / gre a te r trocha nte r

M

S1

S2

M. AS IS

Coccyx N

A

N. S ymphys is pubis a nd gre a te r trocha nte r

B

Figure 5–5. Body sur ace landmarks and localization points. Anterior view (A), Lateral view (B).

CHAPTER 5 GENERAL PRO CEDURAL CO NSIDERATIO NS

81

metastatic bone disease, gastrointestinal or respiratory distress, or patients in shock or victims o stroke. T e use o body sur ace landmarks and localization points (Fig. 5–5) as external indicators o anatomic structures can increase the ease and accuracy o positioning. T ought ul placement o a cushioning sponge, the use o a horizontal beam (“cross-table”) or lateral projections instead o moving the patient (Fig. 5–7), or per orming an examination erect i the recumbent position is uncom ortable are a ew examples o modi cations that a considerate radiographer can make that will result in an appreciative patient, as well as a diagnostic examination. T e radiographer must also be alert to changes in technical actors that may be necessitated by various pathologic processes.

BODYPLANES Body planes are illustrated in Figure 5-1. Positioning descriptions and methodology are described using these planes. T e student radiographer must understand these body planes, their relationship to each other, and to the x-ray beam and image receptor. T e body planes are described below: • Midsagittal or median sagittal plane (MSP): Divides the body into le and right halves • Sagittal plane: Any plane parallel to the MSP • Midcoronal plane (MCP): Divides the body into anterior and posterior halves • Coronal plane: Any plane parallel to the MCP • ransverse/horizontal plane: Perpendicular to the MSP and MCP, and divides the body axially into superior and in erior portions

Po s itio ning Te rmino lo g y Radio g raphic po s itio n Re fe rs to body’s phys ica l pos ition, e.g., re cumbe nt, e re ct, prone, s upine , Tre nde le nburg, e tc. Radio g raphic pro je c tio n De s cribe s the pa th of the CR, e.g., PA (CR e nte rs pos te riorly, exits a nte riorly) Radio g raphic view De s cribe s the body pa rt a s s e e n by the IR, e.g., pa lma r view of the ha nd; infre que ntly us e d Ge ne ral Te rmino lo g y 1. Re cumbe nt/lying down in a ny pos ition • lying on ba ck, fa ce up = supine • lying on a bdome n, fa ce down = prone

• s upine, prone, or la te ra l, us ing horizonta l CR = decubitus 2. Ere ct/upright/s ta nding or s itting up • fa cing the IR = anterior position • with ba ck towa rd IR = posterior position 3. Oblique pos ition—e re ct or re cumbe nt • RAO/Right Anterior Oblique: body rota te d, with right a nte rior a s pe ct ne a re s t the IR • LAO/Left Anterior Oblique: body rota te d, with le ft a nte rior a s pe ct ne a re s t the IR • RPO/Right Posterior Oblique: body rota te d, with right pos te rior a s pe ct ne a re s t the IR • LPO/Left Posterior Oblique: body rota te d, with le ft pos te rior a s pe ct ne a re s t the IR

Figure 5–6. Standard terminology provides descriptions and interpretation o accepted radiologic positioning language. (continued )

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PART II IMAGING PRO CEDURES

Anteroposterior projection

Posteroanterior projection

Right lateral position

Left lateral position

Left posterior oblique position

Right posterior oblique position

Left anterior oblique position

Right anterior oblique position

Figure 5–6. (Continued )

CHAPTER 5 GENERAL PRO CEDURAL CO NSIDERATIO NS

Figure 5–7. Horizontal beam lateral projection o the knee per ormed in supine position on a patient with multiple injuries. A horizontal (“cross-table”) x-ray beam was used to reduce discom ort and risk o urther injury. Observe the bedsheet arti act rom the mattress pad beneath the patient. Use this radiograph to review the skeletal anatomy o the knee and correctly identi y the lettered parts. A, styloid process o bula; B, emur; C, bula; D, patella— base; E, patella—apex; F, patella—body; G, tibia; H, proximal tibio bular articulation; I, neck o bula; J, head o bula; K, tibial tuberosity; L, tibial plateau; M, intercondylar eminence; N, emoral condyle. (Photo Contributor: Stam ord Hospital, Department o Radiology.)

BODYHABITUS In 1916, R. Walter Mills presented an article at the American Roentgen Ray Society meeting in Chicago (published in American Journal o Roentgenology, April 1917) describing “T e Relation o Bodily Habitus to Visceral Form, Position, onus and Motility.” In his article, he coined the terms hypersthenic, sthenic, hyposthenic, and asthenic to describe the various body types. He noted that most physicians came into the eld prejudiced by their early anatomic teachings and had xed conceptions, “which the revelations o the roentgen ray ruthlessly outraged.”

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PART II IMAGING PRO CEDURES

Vertebra(e) Cervical region

Thoracic region

Lumbar region

Sacral and coccygeal regions

Localization Point C1 C5

Mastoid process Thyroid cartilage (Adam’s apple) C7 Vertebra prominens T2–3 Suprasternal (jugular) notch T4–5 Sternal angle T7–8 In erior angle o scapula T9 Xiphoid (ensi orm) process T10 Xiphoid tip T12–L3 Kidneys L1 Transpyloric plane L3 In erior costal margin L3–4 Umbilicus L4 Iliac crest S1–2 Anterosuperior iliac spine (ASIS) Coccyx Symphysis pubis and greater trochanter

Patients come in all shapes and sizes. T e term body habitus re ers to the body’s physical appearance. Variations in body habitus have a signi icant ef ect on the shape, location, and position o thoracic and abdominal organs, and can af ect their unction and motility. Figure 5–2 illustrates how greatly the position o the diaphragm, lungs, and stomach can dif er among the various body habitus. Radiographers should be knowledgeable about the variable characteristics o each habitus and how to use that knowledge when imaging patients o various body habitus. T e hypersthenic habitus is the largest o the our types. T is type is large and heavy; the chest area is short, with a high diaphragm. T e viscera (stomach, large intestine, and gallbladder) are usually high and lateral. T e sthenic habitus is de ned as an average athletic build. Compared to the hypersthenic, it is characterized by a longer chest and abdomen, with viscera located more medially. T e hyposthenic habitus is a slighter version o the sthenic—less athletic/strong. T e asthenic habitus is the smallest/slightest o the our types. T is habitus can be rail-looking, slender, and slight. T e chest is long and the abdominal viscera are located quite low and medial.

SURFACELANDMARKSANDLOCALIZATIONPOINTS

Anatomical/Positioning Terminology The ollowing terms are used to indicate anatomical direction: Superior Toward the upper part o the structure In erior Toward the lower part o the structure Anterior/Ventral Nearer to or at the ront o the body Posterior/Dorsal Nearer to or at the back o the body Medial Nearer the midline o the body Lateral Away rom the midline o the body Proximal Nearer the point o attachment Distal Farther rom the point o attachment Cephalad Toward the head Caudad Toward the eet

A number o sur ace anatomic points and particular vertebral levels are ef ectively used in radiographic positioning. T ese are illustrated in Figure 5–5A (anterior view) and B (lateral view). T e radiographer uses sur ace landmarks that are, bony prominences and projections to identi y anatomic structures and positional accuracy, and to locate internal structures/organs that are known to correspond to the bony prominences or vertebral levels. Accurate use o sur ace landmarks and localization points can ef ectively avoid any need or repeat images. Knowledge o these relationships improves patient-positioning accuracy and accuracy o central ray entry/exit points.

PRELIMINARYSTEPSANDPROCEDURALGUIDELINES Providing skill ul patient care in an orderly ashion is exceedingly important. Having the diagnostic room orderly, with all necessary accessories available be ore bringing the patient in the room is the correct way to begin every diagnostic x-ray procedure. T e ollowing are ordered steps and procedures that help ensure high quality patient care and diagnostic radiographs: 1. Read the request care ully, noting the type o examination, condition o the patient, and mode o travel. (Make mental notes o any modi cations or accessory equipment that may be required.) 2. Prepare the radiographic department. Be certain that the x-ray room is neat and orderly with a clean x-ray table and a resh pillowcase. All accessories needed or the examination should be in the department be ore bringing in the patient.

CHAPTER 5 GENERAL PRO CEDURAL CO NSIDERATIO NS

3. Identi y the correct patient, quickly evaluating any special needs; introduce yoursel and establish rapport en route to the radiographic department, being care ul not to discuss con dential issues within earshot o others. 4. Instruct the patient to change into a dressing gown (i necessary), removing appropriate clothing and objects (e.g., jewelry, dentures, and braided hair) that may cast arti acts within the area o interest (Figs. 5–8 and 5–9). 5. Speak in a well-modulated voice, give a clear and succinct explanation o the procedure, and address any questions or concerns o the patient. Obtain a short pertinent patient history o why the examination has been requested. T e radiographer should explain that a number o dif erent positions may be needed to evaluate the area o interest and may require palpation o bony landmarks and instructions to turn into various positions. 6. Radiography o most structures usually requires a minimum o two projections, usually at right angles to each other. Side-to-side (i.e., le /right) relationships are demonstrated in the rontal projection (Fig. 5–10A), whereas anterior/posterior relationships are seen in the lateral projection (Fig. 5–10B). T is is especially important

Figure 5–8. The posteroanterior projection o the chest 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. (Photo Contributor: Stam ord Hospital, Department o Radiology.)

Skeletal Motion Terminology The ollowing terms are used to indicate anatomical motion:

•

Supination: Turning o the body or arm so that the palm aces orward, with the thumb away rom midline o the body

•

Pronation: Turning o the body or arm so that the palm aces backward, with the thumb toward midline o the body

•

Abduction: Movement o a part away rom the body’s MSP

•

Adduction: Movement o a part toward the body’s MSP

•

Flexion: Bending motion o an articulation, decreasing the angle between associated bones

•

Extension: Bending motion o an articulation, increasing the angle between associated bones

•

Eversion: A turning outward or lateral motion o an articulation, sometimes with external tension or stress applied

•

Inversion: A turning inward or medial motion o an articulation, sometimes with external tension or stress applied

•

Rotation: Movement o a part about its central or long axis

•

Circumduction: Movement o a limb that produces circular motion; circumscribes a small area at its proximal end and a wide area at the distal end

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Figure 5–9. Le t posterior oblique image o the esophagus with a jewelry arti act near the area o interest. The patient must remove clothing and other objects, such as jewelry, rom the area to be examined be ore donning the dressing gown. (Photo Contributor: Stam ord Hospital, Department o Radiology.)

7.

8.

9.

10.

in localizing oreign bodies and tumors, and demonstrating racture displacement or alignment. It is customary and economical to use the smallest size image receptor that will include all the necessary in ormation. T ere ore, the smallest possible anatomic area (consistent with a diagnostic examination) will be irradiated to keep patient dose to a minimum. Use radiation protective shielding, as needed. In radiography o the long bones, every ef ort should be made to include both articulations associated with the injured bone, but it is essential to include at least the articulation nearest the injury. o ensure accurate diagnosis, supplemental images o any anatomic part may be required, or example oblique, axial, tangential, erect, or decubitus. Exposure actors must be correctly adjusted or each change o position. Each image must be accurately labeled with patient in ormation such as name or identi cation number, institution name, date o examination, and side marker. Other in ormation may be included according to institution policy.

CHAPTER 5 GENERAL PRO CEDURAL CO NSIDERATIO NS

A

87

B

C

D

Figure 5–10. A minimum o two projections, at right angles to each other, is the usual minimum requirement or radiographic studies. Side-to-side (le t/right) relationships are demonstrated in the rontal projection (A), whereas anterior/posterior relationships are seen in the lateral projection (B). This is especially important in localizing oreign bodies and tumors, and demonstrating racture displacement or alignment. (Photo Contributor: Conrad P. Ehrlich, MD.) Additional projections can demonstrate details not seen in one projection, especially when determining racture site and position. A Lis ranc racture is clearly demonstrated in (C) at the base o the rst metatarsal’s articulation with the medial cunei orm (AP oot). Position o the ractured distal portions o the second, third, and ourth metatarsals is dif cult to determine without the oblique projection (D).

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IMMOBILIZATIONANDRESPIRATION Motion obliterates recorded detail; thus, it is essential that the radiographer be able to reduce patient motion as much as possible. Several means can be employed to reduce motion unsharpness, but good patient communication is the most important because it is required be ore any other means can be ef ective. T e single most important way to reduce involuntary motion is to use the shortest possible exposure time. Various types o immobilization devices can also be used to ef ectively reduce motion. Motion rom muscular tremors as a result o anxiety or pain is involuntary and can be greatly minimized with good communication, a care ully placed positioning sponge or sandbag, and the use o the shortest exposure time possible. Suspension o patient respiration or parts other than the extremities is an ef ective means o reducing voluntary motion; patient understanding and cooperation is required, thus making good communication the most ef ective means o reducing voluntary motion. T e phase o respiration on which the exposure is made can be essential to the diagnostic quality o the radiographic image. Chest radiography, or example normally requires that the exposure be made on inspiration (the second inspiration or better lling o the lungs). Most abdominal examinations are exposed on expiration. T e phase o respiration on which the exposure is made can also make a signi cant dif erence in the resulting radiographic density (discussed in Part IV).

MODIFIEDANDADDITIONALPROJECTIONS Additional projections/positions are o en required in order to demonstrate the structure(s) o interest (Fig. 5–10C and D). Since human bodies are not identical and pathologic processes are o en unpredictable, routine protocols occasionally require supplemental images. I a patient is unable to assume or maintain the routine position used or a particular examination, the radiographer should be capable o modi ying it to provide the required in ormation. T is is o en a good measure o the radiographer’s skill. Skill ul maneuvering o the x-ray tube and correct placement o the image receptor can o en yield excellent images o an anatomic part di cult or impossible to manipulate. It is not within the radiographer’s scope o practice to supply additional unrequested images, but the radiographer should advise the physician o other positions or modi cations that may provide better visualization o the af ected area.

CHAPTER 5 GENERAL PRO CEDURAL CO NSIDERATIO NS

COMPREHENSION CHECK Congratulations! You have completed your review o this chapter. I you are able to answer the ollowing group o comprehensive questions, you can eel con dent that you have mastered this section. You are then ready to go on to “Registry-type” questions that ollow. For greatest success, do not go to these multiple-choice questions without rst completing the short-answer questions below. 1. Discuss how knowledge o anatomy and pathologic conditions relates to positioning skills (p. 77, 81). 2. Identi y the sagittal and midsagittal, coronal and midcoronal, and transverse (horizontal) planes; describe their relationship to each other (p. 78, 81). 3. Identi y the our types o body habitus and list physical characteristics o each (p. 78, 79, 83, 84). 4. Name, identi y, and describe the quadrants and nine regions o the abdomen (p. 80). 5. Identi y sur ace anatomic localization points and their corresponding vertebrae (p. 80, 84).

6. De ne and identi y various skeletal movement terms (p. 84, 85). 7. Discuss the importance o establishing an orderly sequence o preparation or per orming radiologic examinations (p. 85, 86). 8. Explain the importance o obtaining two images at right angles to each other or most radiologic examinations (p. 85, 88). 9. Discuss the inclusion o articulations in radiography o the extremities (p. 86). 10. List the in ormation that must be included on the radiographic image (p. 86). 11. What is the most e ective means o reducing voluntary and involuntary motion? (p. 86, 87). 12. Why/When might the radiographer be required to modi y the routine projections? (p. 89)

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CHAPTER REVIEW QUESTIONS 1. The plane that passes vertically through the body dividing it into le t and right halves is termed the: (A) Midsagittal plane (B) Midcoronal plane

7. The radiographer should be able to: 1. Take a short patient history prior to the examination

(C) Sagittal plane

2. Modi y routine protocol to obtain similar images in patients unable to move

(D) Transverse plane

3. Evaluate patient condition and needs

2. The position o the asthenic gallbladder, as compared to the position o the sthenic gallbladder, is more:

(A) 1 only (B) 1 and 2 only

(A) Superior and lateral

(C) 1 and 3 only

(B) Superior and medial

(D) 1, 2, and 3

(C) In erior and lateral (D) In erior and medial 3. What is the relationship between the midsagittal and midcoronal planes? (A) Parallel (B) Perpendicular (C) 45 degrees (D) 70 degrees 4. With the patient recumbent and head positioned at a level lower than the eet, the patient is said to be in the: (A) Trendelenburg position (B) Fowler position (C) Decubitus position (D) Sims position 5. Prior to x-ray examinations o the skull and cervical spine, the patient should remove: 1. Dentures 2. Earrings 3. Necklaces (A) 1 only (B) 1 and 2 only (C) 2 and 3 only (D) 1, 2, and 3 6. Image identi cation markers should include: 1. Patient’s name and/or ID number 2. Date 3. A right or le t marker (A) 1 only (B) 1 and 2 only (C) 1 and 3 only (D) 1, 2, and 3

8. The best way to control voluntary motion is: (A) Immobilization (B) Care ul explanation (C) Short exposure time (D) Physical restraint 9. Be ore bringing the patient into the radiographic room the radiographer should: 1. Be certain that the x-ray room is clean and orderly 2. Check that all necessary accessories are available in the room 3. Check that x-ray table is clean and pillowcases are resh (A) 1 only (B) 1 and 2 only (C) 2 and 3 only (D) 1, 2, and 3 10. The lower portion o the costal margin is approximately at the same level as that o the: (A) Midthorax (B) Umbilicus (C) Xiphoid tip (D) Third lumbar vertebra

CHAPTER 5 GENERAL PRO CEDURAL CO NSIDERATIO NS

Answers and Explanations 1. (A) The midsagittal (or median sagittal) plane passes vertically through the midline o the body, dividing it into le t and right halves. Any plane parallel to the MSP is termed a sagittal plane. The midcoronal plane is perpendicular to the MSP and divides the body into anterior and posterior halves. A transverse plane passes across the body, also perpendicular to a sagittal plane. These planes, especially the MSP, are very important re erence points in radiographic positioning. 2. (D) The position, shape, and motility o various organs can di er greatly rom one body habitus to another. The position o the diaphragm, lungs, stomach, gallbladder, and large and small intestines vary greatly with body habitus. The individuals with small extreme habitus (asthenic) have structures lower and more medial, whereas these structures in individuals o the large extreme habitus (hypersthenic) have structures high and lateral (Figs. 5–2 and 5–3). 3. (B) The midsagittal plane passes vertically through the midline o the body, dividing it into le t and right halves. Any plane parallel to the MSP is termed a sagittal plane. The midcoronal plane is perpendicular to the MSP and divides the body into anterior and posterior halves. The transverse plane passes across the body, also perpendicular to a sagittal plane. These planes, especially the MSP, are very important re erence points in radiographic positioning. 4. (A) When the patient is recumbent with his or her head lower than the eet, the patient is said to be in the Trendelenburg position. In the Fowler position, the patient’s head is positioned higher than his or her eet. The decubitus position is used to describe the patient as recumbent (prone, supine, or lateral) with the central ray directed horizontally. The Sims position is the le t anterior oblique position assumed or enema tip insertion. 5. (D) The patient must remove any metallic objects i he or she is within the area o interest. Dentures, earrings, necklaces, and braided hair can obscure bony details in the skull or cervical spine. The radiographer must be certain that the patient’s belongings are cared or properly and returned ollowing the examination (Figs. 5–8 and 5–9). 6. (D) Correct and complete patient in ormation on every radiograph is o paramount importance. Each radiographic image must be accurately labeled with such

patient in ormation as name or identif cation number, institution name, date o examination, and side marker. Other in ormation may be included according to institution policy. 7. (D) The acquisition o pertinent clinical history is one o the most valuable contributions to the diagnostic process. Because the diagnostic radiologist rarely has the opportunity to speak with the patient, this is a crucial responsibility o the radiographer. As the radiographer obtains a brie pertinent clinical history, the radiographer also assesses the patient’s condition by observing and listening. To provide sa e and e ective care, the radiographer must be able to assess the severity o a traumatized patient’s injury, his or her degree o motor control, the need or support equipment, or radiographic accessories. In patients too injured or ill to move, the radiographer should be capable o modi ying routine positions to obtain images with the required anatomic part/in ormation. 8. (B) Motion obliterates recorded detail; it is there ore essential that the radiographer be able to reduce patient motion as much as possible. Even the slightest movement can cause severe degradation o the radiographic image. Suspension o patient respiration or parts other than the extremities is an e ective means o reducing voluntary motion; patient understanding and cooperation is required, thus making good communication the most e ective means o reducing voluntary motion. The single most important way to reduce involuntary motion is to use the shortest possible exposure time. 9. (D) A patient will naturally eel more com ortable and con dent i brought into a clean, orderly x-ray room that has been prepared appropriately or the examination to be per ormed. A disorderly, untidy room and a disorganized radiographer hardly inspire con dence; more likely, they will increase anxiety and apprehension. 10. (D) Sur ace landmarks, prominences, and depressions are use ul to the radiographer in locating anatomic structures not visible externally. The lower costal margin is at about the same level as L3. The umbilicus is at the same approximate level as the L3 to L4 interspace. The xiphoid tip is at about the same level as T10. The ourth lumbar vertebra is at the same approximate level as the iliac crest.

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Imaging Procedures: Anatomy, Positioning, and Pathology

6

OBJECTIVES At the conclusion o this chapter, the student will be able to: • Identi y human anatomy as displayed on illustrations and x-ray images. • Explain accurate positioning details or routine imaging o body parts/systems. • Assess and critique x-ray images or positioning accuracy and quality. • Discuss ways in which routine imaging can be modi ed or trauma, mobile imaging, and other nonroutine circumstances.

THESKELETALSYSTEM Since general radiography involves a great deal o bone imaging, radiographers are required to have a good knowledge o osteology and related pathology. Osteology is the study o bones; there are 206 bones in the human adult skeleton. T e skeletal system o bones serves several unctions: Bones orm the supporting ramework o the body. Bones serve as a reservoir or minerals such as calcium and phosphorus, storing them until the body requires them. T e design o the skeletal ramework is such that it provides protection to the underlying critical and delicate structures. Most bones have prominences (projections, processes, protuberances) and/or cavities (depressions) that have either articular or attachment unctions. I their unction is articular, they provide a sur ace or articulation, that is, joint ormation. I their unction is non-articular, they serve as attachment or muscles providing leverage or movement. T ere are many terms that describe the size, shape, location, or unction o various processes and cavities.

Process: A Bony Elevation. Also Called Protuberance, Prominence, or Projection

• • • •

Condyle: a rounded process for attachment

• • • • •

Facet: small smooth process for articulation

•

Tubercle: a small rounded process for attachment

•

Tuberosity: a large rounded process for attachment

Coracoid: a beak-like process Coronoid: a crown-like process Epicondyle: smaller projection superior to a condyle Malleolus: a club-shaped process Spine or spinous process: a sharp projection Styloid: a long, pointed process Trochanter: a very large rounded process for attachment

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Cavity: A Bony Depression

• • • • •

Antrum: a nearly enclosed cavity

•

Fovea: a ditch or cup-like depression, usually for attachment

• • •

Meatus or Canal: a tube-like passageway

Groove: a shallow, linear depression Fissure: a narrow slit Foramen: a hole in a bone Fossa: a furrow or shallow depression for articulation

Sinus: a nearly enclosed cavity Sulcus: a furrow

Functions o Skeletal System

• • • • •

Support Reservoir for minerals Muscle attachment/movement Protection Hematopoiesis

Bone tissue, or osseous (os = bone) tissue, is a specialized type o dense connective tissue. T is tissue consists o bone cells (osteocytes) embedded in a nonliving matrix composed o calcium and collagen bers. T ere are two types o osseous tissue: cancellous (spongy) and compact (hard, cortical) (Fig. 6–1A). T e structural unit o compact bone tissue is the haversian (osteon) system. One haversian system, or osteon, consists o a central haversian canal surrounded by concentric cylinders o osteocytes within the calcium matrix. Cancellous, or spongy, bone tissue has a reticular or latticework-type structure. T is network o lattice-like bone is re erred to as trabeculae. T ese trabeculae orm little spaces/septa lled with red bone marrow. T e site o close approximation o two or more bones is an articulation, or joint. T e study o bony articulations is termed arthrology. T ere are three classi cations o bony articulations. Synarthrotic joints are immovable; since brous tissue connects the bony contiguous sur aces, they are also described as brous articulations. T e sutures o the cranium are examples o synarthrotic joints. Amphiarthrotic joints, also described as cartilaginous, are partially movable. T e intervertebral joints (between vertebral bodies) and the symphysis pubis are examples o amphiarthrotic joints. 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 (their names describe their movements). T e ollowing list identi es types o diarthrotic joints, describes their movement(s), and gives examples o each:

Bone Tissue Types

• •

Cortical (hard, compact) Cancellous (spongy)

Articula r ca rtila ge S pongy (ca nce llous ) bone

Compa ct bone (cortica l) Nutrie nt fora me n

Endos te um Pe rios te um

D M

Me dulla ry cavity

L E M

Nutrie nt a rte ry

D

Dia phys is (s ha ft)

D M E

E M

A

B

C

Figure 6–1. (A) Long bone anatomy. (B) Child’s hand, with epiphyses (E), metaphyses (M), and diaphyses (D) indicated. (C) Child’s ankle, demonstrating epiphyseal plates of distal tibia and bula. (Photo Contributor: Stamford Hospital, Department of Radiology.)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

Gliding (plane)

Ball and socket (spheroid)

•

The simplest motion, least movement, smooth/sliding motion

•

•

Intercarpal and intertarsal joints, acromioclavicular, and costovertebral joints

Permits exion, extension, adduction, abduction, rotation, and circumduction with more motion distally and less proximally

•

Shoulder and hip

Plane jo int (inte rca rpa l)

Ball-and-s o cke t jo int (hume ros ca pula r) He a d of hume rus

S ca pula

Ca rpa l bone s

Pivot (trochoid)

Condyloid (ellipsoid)

• •

•

Permits exion, extension, abduction, adduction, and circumduction (no axial)

•

Radiocarpal joint and metacarpophalangeal joints (2–5)

Permits rotation around a single axis Proximal radioulnar joint and atlantoaxial joint

Pivo t jo int (ra dioulna r)

Ra dius

Co ndylar jo int (me ta ca rpopha la nge a l)

Ulna

Me ta ca rpa l bone

P ha la nx

Hinge (ginglymus)

Saddle (sellar)

• •

•

Permits exion, extension, adduction, adduction, and circumduction (no rotation)

•

First carpometacarpal joint (thumb)

Permits exion and extension Elbow, interphalangeal joints, and ankle

Hume rus

Hing e jo int (hume roulna r)

S addle jo int (tra pe ziome ta ca rpa l)

Me ta ca rpa l bone

Ulna

Bicondylar (biaxial)

• •

Ca rpa l bone

Principal motion in one direction; limited rotation motion TMJ, knee Bic o ndylar (bia xia l)

Condyle s

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Articular Classi cations Category

Structure

Function

Synarthrotic Fibrous Immovable Amphiarthrotic Cartilaginous Partially moveable Diarthrotic Synovial Freely moveable

Arthritis is de ned as in ammation o a joint; it is a common a iction o en accompanied by pain, swelling, sti ness, and/or de ormity. It always involves damage to articular cartilage, but the causes are numerous; that is, there are many types o arthritis. T e most common type o arthritis is osteoarthritis, or degenerative arthritis. T e incidence o osteoarthritis increases with age, but is not considered a normal part o aging. T e term osteoporosis describes a condition characterized by loss o bone mass, predisposing bones to racture. T roughout li e, healthy bone undergoes growth and resorption—at appropriate times and in appropriate places, as the bones adapt themselves to muscular activity, growth, mechanical pressures, and so on. In osteoporosis, this remodeling ails to occur normally and more bone is resorbed than is replaced; thus, the skeleton loses strength as a result o demineralization. Among the risk actors or osteoporosis are being emale, postmenopausal, Caucasian or Asian, having a small skeletal rame, a amily history o osteoporosis, and a sedentary li estyle.

THEAPPENDICULARSKELETON T e appendicular skeleton (Fig. 6–2; shaded areas) consists o the limbs (appendages or extremities), arms, legs, and shoulder and pelvic girdles. Parts o most o these bones serve as attachment or muscles, thereby creating leverage or movement. Sur aces o adjacent bones connect to orm bony articulations that promote movement. Bones are classi ed as long, short, at, and irregular. Many o the bones comprising the limbs are long bones. Long bones have a sha (diaphysis or body) and two extremities (proximal and distal ends). T e sha (or diaphysis) (Fig. 6–1B) o long bones is the primary ossi cation center during bone development. It is composed o compact tissue and covered with a membrane called periosteum. T e epiphyses o long bones are located at the extremities o the long bone and are the secondary ossi cation centers (Fig. 6–1B and C). Within the sha o a long bone is the medullary cavity, containing bone marrow and lined by a membrane called endosteum. In adults, yellow marrow occupies the 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. T e secondary ossi cation center, the epiphysis, is separated rom the diaphysis in early li e by a layer o cartilage, the epiphyseal plate. As bone growth takes place, the epiphysis becomes part o the larger portion o bone. T e epiphyseal plate disappears, but a characteristic line remains and is therea er recognizable as the epiphyseal line. T e metaphysis is the wider portion o bone adjacent to the epiphyseal plate (Fig. 6–1B and C). T e metaphysis includes the connecting cartilage that enables bony growth during childhood bony development; it disappears in adulthood. An apophysis is a normal outgrowth o bone that eventually becomes a bony prominence or muscle/tendon attachment. T e articular ends o bones are covered with hyaline cartilage. Hyaline cartilage is the most abundant type o cartilage. T is tough, glossy material covers the articular sur aces o long bones and orms the anterior ends o the ribs (costal cartilage). It is also ound in the bronchi, trachea, and larynx. T e membranous covering o hyaline cartilage is perichondrium.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

S kull

Ce rvica l ve rte bra S houlde r girdle

Clavicle S ca pula

S te rnum Ribs Rib ca rtila ge

Bone s of the che s t

Hume rus

Bone s of the a rm Ra dius Ilium S a crum Coccyx

Ulna

Bone s of the wris t a nd ha nd

Bone s of the hip a nd pe lvis

Ca rpa ls Me ta ca rpa ls P ha la nge s Fe mur

Pa te lla

Bone s of the le g

Fibula Tibia

Ta rs a ls Me ta ta rs a ls

Bone s of the a nkle a nd foot

P ha la nge s

Figure 6–2. The appendicular skeleton (shaded); the axial skeleton (unshaded).

Upper Limb and Shoulder Girdle Hand, Fingers, and Thumb. T e hand (Fig. 6–3A and B) is composed o ve metacarpal bones, corresponding to the palm o the hand, and 14 phalanges, the ngers. T e second through h ngers have three phalanges each (proximal, middle, and distal rows) and the rst nger, or thumb (pollex), has two phalanges (proximal and distal). T e rows o phalanges articulate with each other orming proximal and distal interphalangeal joints (IPJs) (hinge/ginglymus joints), permitting exion and extension motion. T e bases o the proximal row o phalanges articulate with the heads o the metacarpals to orm the (condyloid/ellipsoid) metacarpophalangeal joints (MCPs), which permit exion and extension, abduction and

97

98

PART II IMAGING PRO CEDURES

3 2

4

H K

G

5 J

P ha la nge s

L

F

1 I

E D M B

M

Me ta ca rpa ls

A

Tra pe zoid Tra pe zium Ca pita te S ca phoid Ra dius

C O

Ha ma te

N R W V

Trique trum P is iform

Q

P

U S

T Y X

Luna te

Z

Ulna B

A

C

Figure 6–3. (A) Posterior aspect of the right hand and wrist. (B) PA projection of the hand; note that an oblique projection of the rst metacarpal and phalanges is obtained. A, metacarpal (shaft/body), rst digit (thumb/pollex); B, third metacarpal (shaft/body); C, base of the third metacarpal; D, neck of the third metacarpal; E, head of the third metacarpal; F, proximal phalanx, second digit; G, middle phalanx, third digit; H, distal phalanx, fourth digit; I, second metacarpophalangeal joint; J, proximal interphalangeal joint, third digit; K, distal interphalangeal joint, fourth digit; L, ungual tuft, fth digit; M, sesamoid bones; N, trapezium/greater multangular; O, trapezoid/lesser multangular; P, capitate/os magnum; Q, hamate/unciform; R, scaphoid; S, lunate/ semilunar; T, triquetrum/triangular; U, pisiform; V, radiocarpal (wrist) joint; W, radial styloid process; X, distal radioulnar articulation; Y, ulnar styloid process; Z, head of ulna. (C) Boxer fracture (neck of the fth metacarpal). (Boxer fx image courtesy of David Sack, BS, RT (R), CRA, FAHRA.)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

adduction, and circumduction. T e bases o the metacarpals articulate with each other and the distal row o carpals at the carpometacarpal joints. T e rst carpometacarpal joint (thumb) is a saddle/sellar joint, permitting exion and extension, abduction and adduction, and circumduction. raumatic ractures o the hand and wrist are common. Fractures o the distal (ungual) phalangeal tu s usually occur rom crushing injuries, such as being closed in car doors or struck with a hammer. Metacarpal and phalangeal ractures are common ractures and are o en accompanied by dislocations o the MCP and IPJ. In ractures o the metacarpal sha s, the bony ragments are o en displaced posteriorly and can be rotated as well. A type o hand racture occasionally seen is a Boxer’s racture. A Boxer’s racture involves the distal end (neck) o the ourth or h metacarpal and o en includes posterior displacement/angulation o the ractured metacarpals’ proximal structures (Fig. 6–3C). T e racture is termed Boxer because it is usually caused by the blow o a clenched st (as in boxing) against a hard, unyielding object such as a muscular/bony body part or a structure like a wall. Wrist. T e wrist, as seen in the PA projection o hand (Fig. 6–3A and B), is composed o eight carpal bones arranged in two rows (proximal and distal). T e proximal row consists o , rom lateral to medial, the scaphoid, the lunate/semilunar, the triangular/triquetrum, and the pisiorm. T e distal row, rom lateral to medial, consists o the trapezium/ greater multangular, the trapezoid/lesser multangular, the capitate/os magnum (the largest carpal), and the hamate/unci orm (which has a hook-like process, the hamulus). T e joints o the wrist include the articulations between the carpals (intercarpal joints), which provide a gliding motion, and the radiocarpal joint (between the distal radius and scaphoid), which provides exion and extension as well as abduction and adduction. Most carpal ractures involve the scaphoid and o en result rom a all onto an outstretched dorsi exed hand. Symptoms include tenderness and swelling over the “anatomic snu box.” Special projections can be used to detect scaphoid hairline ractures (see Fig. 6–12B). T e second most commonly ractured carpal is the triquetrum. Delayed union or nonunion o these ractures can be due to damage to the nutrient artery during the initial trauma event. Unstable ractures, or cases o nonunion, may be treated with open reduction and internal xation o the displaced/ununited racture. Carpal tunnel syndrome is a pain ul condition o the wrist. I the anteroposterior (AP) diameter o the tunnel is diminished, the median nerve, which passes through the tunnel, is impinged upon, thus causing severe pain and disability in the a ected hand and wrist. Surgical decompression o the carpal tunnel can provide signi cant relie . Forearm. T e bones o the orearm, or antebrachium (Fig. 6–4), consist o the radius (laterally) and ulna (medially), which participate in the ormation o the elbow joint proximally and the wrist distally. T e distal ulna presents a head and styloid process and articulates with the distal radius to orm the distal radioulnar joint. T e ulna is slender distally but enlarges proximally and becomes the larger o the two bones o the orearm. At its proximal end, the ulna presents the

99

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PART II IMAGING PRO CEDURES

S e miluna r notch

Ole cra non

Coronoid proce s s

He a d Ne ck

Ra dia l notch

Ra dia l tube ros ity

Ulna

Ulna Ra dius

He a d

S tyloid proce s s e s of ulna a nd ra dius A

Ante rio r vie w

Po s te rio r vie w

B

C

Figure 6–4. (A) Bones of the left forearm. (B) AP projection of the right forearm. Arm in extension with hand supinated to avoid overlap of radius and ulna. (C) Lateral projection of the right forearm. Elbow exed 90° with the hand and wrist in lateral position; humeral epicondyles are superimposed (interepicondylar line ). (Photo Contributor: Conrad P. Ehrlich, MD.)

Carpal Bones Proximal Row, Lateral to Medial

• • • •

Scaphoid Lunate/semilunar Triquetrum/triangular Pisiform

Distal Row, Lateral to Medial

• • • •

Trapezium/greater multangular Trapezoid/lesser multangular Capitate/os magnum Hamate/unciform

olecranon process (posteriorly) and coronoid process (anteriorly) that are joined by a large articular cavity, the semilunar, or trochlear, notch. T e coronoid process ts into the humeral coronoid ossa during exion and the olecranon process ts into the humeral olecranon ossa during extension. Just distal and lateral to the semilunar notch is the radial notch, which provides articulation or the radial head to orm the proximal radioulnar articulation. Just as the ulna is the principal bone associated with the elbow joint, the radius is the principal bone associated with the wrist joint. Fracture o the distal radius is one o the most common skeletal ractures. T e distal radius presents a styloid process laterally; the ulnar notch is located medially, helping orm the distal radioulnar articulation. T e distal sur ace o the radius (carpal articular sur ace) is smooth or accommodating the scaphoid and lunate in the ormation o the radiocarpal joint. T e proximal radius has a cylindrical head with a medial sur ace that participates in the proximal radioulnar joint; its superior sur ace articulates with the capitulum o the humerus. T e radius is the most requently ractured bone o the arm.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

A

101

B

Figure 6–5. Colles fracture with plate and screw xator in place. PA (A) and lateral (B). Note scaphoid fracture also seen in Fig. A. (Photo Contributor: Maryjane Hatch.)

Fractures o the radial head and neck requently result rom a all onto an outstretched hand with the elbow partially exed. Severe ractures are o en accompanied by posterior dislocation o the elbow joint. Colles ractures (named a er the Irish surgeon/anatomist who rst described it: Abraham Colles) o the distal radius usually result rom a all onto an outstretched hand with the arm extended. ypically, the radius exhibits a transverse racture with posterior displacement; the racture is o en accompanied by a racture o the ulnar styloid process. Particularly susceptible are adults older than 60 years o age with osteoporosis. Fractures o the ulnar styloid, when present, usually occur due to hyperabduction o the hand. When surgical repair with internal xator is required, depending on the racture, either stainless steel/titanium metal pins can be used or xation with plate and screws (Fig. 6–5). Elbow. T e distal humerus articulates with the radius and ulna to orm the elbow joint (Fig. 6–6). 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 distal humerus and articulates with the semilunar notch o the ulna. Just proximal to the capitulum and trochlea are the lateral and medial epicondyles; the medial is more prominent and palpable. T e olecranon ossa is ound on the posterior distal humerus and unctions to accommodate the olecranon process with the elbow in extension (Figs. 6–6 and 6–7). Lateral epicondylitis (tennis elbow) is a pain ul condition caused by prolonged rotary motion o the orearm. Dislocations o the elbow can also occur rom a all onto an outstretched hand, sending the orce to the elbow. I there is also a turning motion, the elbow is dislocated. One or both bones o the orearm can be involved; a posterior dislocation is the most common and is requently accompanied by a radial head racture. Rotation o the radial head can be palpated on the posterior lateral sur ace o the elbow, with the elbow in extension. T ere are three important at pads associated with the elbow. T e anterior and posterior at pads are located on the corresponding

102

PART II IMAGING PRO CEDURES

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

A

Ante rio r

Po s te rio r

B

C Ca pitulum

Ra dia l ne ck

Coronoid proce s s Hume rus

Ra dia l he a d

Ra dia l tube ros ity

La te ra l e picondyle

Ole cra non proce s s S e miluna r/ trochle a r notch D

Ulna Late ral

E

Figure 6–6. (A) Anterior and (B) posterior aspects of the bony articulation of the right elbow joint. (C) AP projection of the elbow. (Photo Contributor: Conrad P. Ehrlich, MD.) (D) and (E). Medial and lateral aspects of the bony articulation of the right elbow joint. (Photo Contributor: Stamford Hospital, Department of Radiology.)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

He a d

Inte rtube rcula r groove

Gre a te r tube rcle

Le s s e r tube rcle Ana tomic ne ck

S urgica l ne ck

De ltoid tube ros ity

Ra dia l groove Coronoid fos s a

Ole cra non fos s a

Ra dia l fos s a

La te ra l e picondyle Me dia l e picondyle Trochle a Po s te rio r view

Ca pitulum Trochle a Ante rio r vie w

Figure 6–7. The humerus (posterior and anterior views).

portions o the distal humerus, superimposed but separated by a membranous portion o the joint capsule. T e anterior at pad (composed o two small radial and coronoid at pads) lls the shallow coronoid ossa and is readily visualized in the lateral projection o the normal elbow. T e posterior at pad lls the deeper olecranon ossa and is there ore not visualized in the normal lateral elbow projection. In the presence o injury and joint e usion, the anterior at pad is displaced anteriorly and upward while the posterior at pad is displaced posteriorly. T e classic “sail sign” or “spinnaker sail sign” (i.e., billowing sail) seen anteriorly in a lateral elbow radiograph o en indicates a radial head or neck racture. T e supinator at pad/stripe is located at the proximal radius just anterior to the head, neck, and tuberosity. T is at pad can also become more apparent i injury causes uid buildup to displace it. Humerus. T e deltoid tuberosity is ound on the anterolateral sur ace o the humeral sha . T e large, round humeral head is covered with hyaline cartilage and articulates with the scapula’s glenoid ossa. T e anatomic neck marks the location o the used epiphyseal plate in the adult and separates the head and metaphysis. T e proximal humerus presents two protuberances on its anterior sur ace; the greater tubercle is lateral and the lesser tubercle is medial. Between the tubercles is the bicipital, or intertubercular, groove. T e humeral sha narrows just distal to the tubercles at the point o the surgical neck.

103

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PART II IMAGING PRO CEDURES

S upra s ca pula r notch

Cora coid proce s s

S ca pula r s pine

Acromion proce s s

S upe rior a ngle

Gle noid fos s a

S upra s pinous fos s a Ne ck Infra s pinous fos s a

Hume rus Body La te ra l a ngle (or infra gle noid tube ros ity) Ve rte bra l borde r

Axilla ry borde r

Infe rior a ngle A

B

Figure 6–8. (A) Posterior aspect of the right scapula. (B) Scapular neck fracture, lateral projection. (Photo Contributor: David Sack, BS, RT (R), CRA, FAHRA.)

Articulation Summary: Upper Limb and Shoulder Girdle

• • • •

Acromioclavicular Sternoclavicular Shoulder (glenohumeral) Elbow—three articulations:

• b/w humeral trochlea and semilunar/ trochlear notch

• b/w capitulum and radial head • proximal radioulnar joint • •

Distal radioulnar

• • • •

Intercarpal

Radiocarpal (distal radius with scaphoid and lunate)

Humeral ractures most o en a ect the surgical neck region rather than the distal end o the bone. Fractures o the proximal humerus usually involve impaction o the sha into the humeral head. Many humerus ractures are associated with osteoporosis or other pathologies, as a result o a all or direct trauma. Fractures o the greater tubercle can result rom a direct blow or as a consequence o orcible pull o the associated muscles. Shoulder. T e shoulder (pectoral) girdle consists o the scapulae (Fig. 6–8A) and clavicles (Fig. 6–9). While the S-shaped clavicle (collar

S te rna l a rticula r s urfa ce

Acromia l a rticula r s urfa ce Infe rio r view

Carpometacarpal

Conoid tube rcle

Metacarpophalangeal Interphalangeal

S te rna l extre mity

Acromia l extre mity S upe rio r view

Figure 6–9. The right clavicle (inferior and superior views).

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

bone) is the rst bone to ossi y ( h week o gestation), it is usually the last bone to completely use at approximately 22 to 25 years o age and is one o the most commonly ractured bones in young people. Clavicular ractures are usually treated non-operatively; good outcome is most o en achieved using a shoulder sling or gure-o -eight brace. T e medial end o the clavicle 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. T e scapula is a at bone, shaped like a triangle, with a costal sur ace that lies against the upper posterior rib cage. T e scapula has a superior (or medial) angle, a superior border, a medial (or vertebral) border, a lateral (or axillary) border, and an in erior angle, or apex. Its superior border presents a scapular notch and, projecting anteriorly just medial to the humeral head is the palpable coracoid process. T e scapular spine divides the posterior sur ace into a supraspinatus ossa and in raspinatus ossa; the acromion process is the lateral extension o the scapular spine. T e glenoid ossa is on the lateral aspect o the scapula and, with its articulation with the humeral head, orms the (ball and socket) shoulder joint. T e shoulder labrum is a ring o brocartilage that extends rom the rim o the glenoid cavity, acting like a suction cup and deepening the joint “socket.” Labral injuries o the shoulder o en involve a tear, o en a SLAP tear (i.e., superior labrum anterior to posterior). SLAP tears occur most o en as throwing injuries, or example, baseball pitchers, but can also occur as a result o a all or blow to the shoulder. Because many surrounding muscles protect the scapula, ractures are not common. O those ractures that do occur, two-thirds o them involve the scapular neck (Fig. 6–8B) and do not involve the articular sur aces. Most scapular ractures are a result o direct trauma to the shoulder region, very o en as a result o motor vehicle accident. Scapular ractures can also be related to injuries to the clavicle, sternum, or ribs. T e rotator cuf is largely responsible or abduction and internal rotation movements and is composed o the supraspinatus, in raspinatus, teres minor, deltoid, and subscapularis muscles. Rotator cuf injuries are o en a result o acute injury or chronic wear and tear. Injuries to the rotator cu include tendonitis, impingement, and tear. Long-standing tendonitis can lead to calci cation: calci c tendonitis. T e articular capsule o the shoulder is loose, not only permitting a great range o movement but also making it susceptible to dislocation. T e majority o shoulder dislocations are anterior, almost always associated with trauma. As the humeral head is orced anteriorly rom the glenoid ossa, it is also o en associated with injury to the joint capsule and detachment o the labrum rom the glenoid ossa. Fracture o the humeral head, neck, or greater tuberosity can also occur at the time o dislocation. Positioning. Positioning o the upper limb and shoulder girdle requires a thorough knowledge o the anatomy concerned as well as an awareness o possible pathologic conditions and their impact on positioning limitations and technical actors.

105

Rotator Cuf Muscles

• • • • •

Supraspinatus Infraspinatus Teres minor Deltoid Subscapularis

List o Abbreviations and Symbols Used in the Tables AC ASIS AP ≈ b/w CMC CR ° DIP dist EAM fx > ″ IOML IPJ IR jt kV lat LAO LPO < MCP MTP MSP m/w OID Obl OML

PA PIP proj prox RAO RPO SID w/ w/o

Acromioclavicular Angle Anterior superior iliac spine Anteroposterior Approximately (about) Between Carpometacarpal joint Central ray Degrees Distal interphalangeal joint Distal External auditory meatus Fracture Greater than Inch(es) Infraorbitomeatal line Interphalangeal joint Image receptor Joint Kilovoltage Lateral Left anterior oblique Left posterior oblique Less than Metacarpophalangeal joint Metatarsophalangeal joint Midsagittal plane Midway Object-to-image receptor distance Oblique Orbitomeatal line Parallel to Perpendicular to Posteroanterior Proximal interphalangeal joint Projection Proximal Right anterior oblique Right posterior oblique Source-to-image receptor distance With Without

106

PART II IMAGING PRO CEDURES

Radiopaque objects such as watches, bracelets, and rings should be removed whenever possible because they can obscure important anatomic in ormation. T e patient must be instructed regarding the importance o remaining still, and immobilization devices such as sandbags or sponges should be used as required. T e shortest possible exposure time should be employed, especially when involuntary motion can be a problem, as with trauma, pediatric, or geriatric patients. Most upper limb examinations are more com ortably and accurately positioned with the patient seated at the end o the x-ray table, with the orearm and elbow resting on the x-ray table. Most can be per ormed tabletop (i.e., without a Bucky grid); the humerus, shoulder, clavicle, and scapula usually require the use o a grid. Suspended respiration is suggested or radiography o the proximal portion o the upper limb and shoulder girdle. Patients must be adequately shielded. T e use o just a ew important bony landmarks and their correct placement with respect to the IR are the basis or accurate positioning. Rotation o the arm and placement o the humeral epicondyles in correct relationship to the IR is the oundation o orearm, elbow, and shoulder positioning. Positioning o the wrist and hand uses the radial and ulnar styloid processes, bending maneuvers (i.e., radial and ulnar exion), and MCP, DIP, and PIP joints. Positioning o the orearm, elbow, humerus, and shoulder requires particular attention to the relationship between the humeral epicondyles and IR. ables 6–1 through 6–11 provide a summary o routine and requently per ormed special positions/projections o the upper limb and shoulder girdle:

TABLE6–1. The Hand Hand

Position o Part

PA

• • •

Hand pronated Elbow exed 90º Fingers extended slightly apart

Central Ray Directed •

3rd MCP

Structures Included/Best Seen •

•

PA carpals, metacarpals, phalanges, their articulations (Fig. 6–10A) Oblique projof the thumb

This projection is often performed to include the wrist for bone age studies; 30” SID is sometimes recommended, with the CR entering the head of the third metacarpal. Oblique

• •

Elbow exed 90º Hand and forearm 45° oblique

•

3rd MCP

•

•

Lateral in extension

• • •

Lateral in exion

• •

Elbow exed 90º Fingers extended Wrist lateral, ulnar surface down

•

Elbow exed 90º Fingers slightly exed and superimposed

•

MCPs

•

•

MCPs

•

•

Oblique proj of the carpals, metacarpals, phalanges, their articulations Use of “ nger sponge” places jts IR and opens jt spaces (Fig. 6–10B) Superimposed carpals, metacarpals, phalanges, their articulations Decrease 10 kV for foreign body Superimposed carpals, metacarpals, phalanges, their articulations Shows ant/post x displacement

A an lateral with the ngers separated is often performed to better visualize each phalange.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

A

107

B

Figure 6–10. PA (A) and oblique (B) projections of the hand. (Photo Contributor: Stamford Hospital, Department of Radiology.)

TABLE6–2. The Thumb Thumb

Position o Part

AP

•

Dorsal surface adjacent and

Central Ray Directed IR

•

MCP

Structures Included/Best Seen AP proj of rst digit Three articulations should be seen: CMC, MCP, and IPJ

• •

PA

• •

Lateral

• •

Palmar surface IR OID is increased

•

Lat surface adjacent to IR Fingers elevated and resting on sponge

•

MCP

PA proj of rst digit Three articulations should be seen: CMC, MCP, and IPJ

• •

MCP

Lat proj of rst digit Three articulations should be seen: CMC, MCP, and IPJ

• •

TABLE6–3. The Fingers Fingers

Position o Part

PA

• • •

Lateral

• • •

Central Ray Directed

Structures Included/Best Seen

Hand pronated Fingers extended Elbow exed 90º

•

PIP

•

PA proximal, middle, and dist phalanges (usually entire hand examined in this position)

Elbow exed 90º Forearm lat Finger(s) extended and

•

PIP

•

Lat of proximal, middle, and distal phalanges Second and third digits are done radial side down Fourth and fth digits are done ulnar side down Three articulations should be seen: MCP, PIP, DIP

•

IR

• •

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PART II IMAGING PRO CEDURES

TABLE6–4. The Wrist Wrist

Position o Part

PA

•

•

Lateral

•

•

PA semipronation oblique

• •

AP semisupination oblique

•

PA ulnar exion/ deviation

•

PA radial exion/ deviation

•

Scaphoid (Stecher)

•

Carpal canal (Gaynor–Hart)

A

•

•

•

•

Central Ray Directed

Hand pronated w/ MCPs slightly exed Elbow exed 90º

•

Elbow exed 90º, ulnar surface down Radius and ulna superimposed

•

Elbow exed 90º Wrist 45º to IR, ulnar surface down

•

Arm extended 45º to IR Ulnar surface down

•

Position as PA wrist Evert hand (laterally) without moving forearm

•

Position as PA wrist Move elbow toward body w/o moving hand/wrist

•

Forearm (a) pronated or (b) pronated and elevated 20º

•

Hyperextend wrist w/ palm vertical

•

midcarpal

Structures Included/Best Seen •

•

midcarpal region

• •

midcarpal region

•

•

midcarpal

• •

•

scaphoid

PA carpals, prox metacarpals, dist radius, and ulna (Fig. 6–11A) Flexion o MCPs reduces OID Lat superimposed carpals, prox metacarpals Superimposed dist radius and ulna (Fig. 6–11B) Scaphoid and other lat carpals (trapezium and trapezoid) and their interspaces (Fig. 6–11C) Magni cation imaging can be useful to demonstrate scaphoid hairline fx (Fig. 6–12B) Pisiform, triquetrum, hamate Medial carpals and their interspaces

•

Scaphoid and other lat carpal interspaces Reduces oreshortening o scaphoid

•

Medial carpal interspaces (Fig. 6–12)

(a) 20º toward elbow (b) scaphoid

•

Scaphoid w/o oreshortening and self-superimposition

25–30º into long axis of hand

•

Carpal canal (tunnel ) Trapezium, scaphoid, capitate, triquetrum, and pisiform

midcarpal region

B

•

•

C

Figure 6–11. (A) PA projection of the wrist. Flexion of the metacarpophalangeal joints reduces OID. (B) Lateral projection of the wrist. (C) Semipronation oblique projection of the wrist. (Photo Contributor: Conrad P. Ehrlich, MD.)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

A

109

B

Figure 6–12. (A) Radial exion/deviation maneuver of the left wrist. Radial exion/deviation is used to better demonstrate the medial carpals (pisiform, triangular, hamate, and medial aspect of capitate and lunate). (Photo Contributor: Stamford Hospital, Department of Radiology.) (B) Magni cation image of the fractured carpal scaphoid. (Photo Contributor: David Sack, BS, RT (R), CRA, FAHRA.)

TABLE6–5. The Forearm Forearm

Position o Part

AP

•

•

•

Lateral

• •

•

Central Ray Directed

Forearm supinated and extended Interepicondylar line IR Shoulder and elbow on the same plane

•

Elbow exed 90º Epicondyles superimposed and interepicondylar line IR Hand lat, shoulder, and elbow on the same plane

•

midforearm

Structures Included/ Best Seen •

•

midforearm

•

•

AP radius and ulna, including wrist and elbow jts (Fig. 6–13A) Forearm must be supinated to avoid overlap of radius and ulna Radius and ulna superimposed distally Lat proj of radius, ulna, elbow, wrist jts (Fig. 6–13B)

A

B

Figure 6–13. (A) AP projection of the forearm. The hand must be supinated to avoid overlap of the proximal radius and ulna. (B) Lateral projection of the forearm. Humerus should be on the same plane as the forearm to superimpose humeral epicondyles. (Photo Contributor: Conrad P. Ehrlich, MD.)

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PART II IMAGING PRO CEDURES

TABLE6–6. The Elbow Elbow

Position o Part

AP

•

•

Central Ray Directed

Forearm supinated and extended Interepicondylar line IR

•

Structures Included/Best Seen

elbow jt m/w b/w epicondyles

• • •

AP elbow jt (Fig. 6–14A) AP prox radius and ulna, dist humerus Radial head and tuberosity partially superimposed on ulna

Note: An elbow in AP partial exion, unable to be extended, requires two projections to achieve an AP elbow: (1) humerus is placed the IR (with elbow still in partial exion) and the CR is elbow jt; (2) orearm is placed the IR (with elbow still in partial exion) and the CR is elbow jt. Thus, an AP of the dist humerus and proximal forearm are obtained separately. A greater degree of elbow exion can require a 5 to 10° angle into the joint. (An AP with the CR directed the exed elbow demonstrates a “closed” jt space.) Lateral

• • •

Internal (medial) oblique

•

External (lateral) oblique

•

•

• •

Trauma axial lateral (Coyle)

•

•

G F

•

Arm extended, palm down Interepicondylar line 45º to IR

•

Forearm extended and rotated laterally Radial surface down Interepicondylar Iine 45º to IR

•

(a) Elbow exed 90º, hand pronated (b) Elbow exed 80º, hand pronated

•

elbow jt at the epicondyles

• • •

•

elbow jt midway b/w epicondyles

•

elbow jt midway b/w epicondyles

•

(a) To elbow, at 45º toward shoulder (b) From shoulder to elbow, at 45º

•

•

•

• •

Lat elbow jt, prox radius, ulna, dist humerus Radial head partially superimposed on ulna Olecranon process in pro le (Fig. 6–14B) Oblique elbow jt Coronoid process in pro le (Fig. 6–14C) Oblique elbow jt Radial head, neck, and tuberosity free from superimposition of ulna These replace lat and med obliques when patient unable to extend arm For radial head For coronoid process

C

B

A

Elbow exed 90º Interepicondylar line IR Forearm and wrist lateral

E

D

B D

E

F

G A

D

A

C

B

R A

C

B

C

Figure 6–14. (A) AP projection of the elbow; radial head and tuberosity have correct partial superimposition on the ulna. A, lateral epicondyle; B, olecranon process; C, medial epicondyle; D, trochlea; E, coronoid process; F, proximal radioulnar articulation (or radial notch of ulna); G, capitulum. (Photo Contributor: Conrad P. Ehrlich, MD.) (B) Lateral projection elbow, elbow exed 90°, and humeral epicondyles superimposed. A, shaft of ulna; B, semilunar/trochlear notch; C, olecranon process; D, coronoid process; E, radial head; F, radial neck; G, radial tuberosity. (Photo Contributor: Stamford Hospital, Department of Radiology.) (C) Medial (internal) oblique view of the elbow; the coronoid process is seen free of superimposition. A, radial head; B, olecranon fossa; C, medial epicondyle; D, coronoid process. (Photo Contributor: Stamford Hospital, Department of Radiology.)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

111

TABLE6–7. The Humerus Humerus

Position o Part

AP

•

Lateral

• •

Central Ray Directed

Arm extended and supinated; interepicondylar line IR

•

Elbow exed 90º Interepicondylar line

•

Structures Included/Best Seen

midhumerus

AP humerus, includes both jts Greater tubercle in pro le

• •

midhumerus

Lat humerus, includes both jts Lesser tubercle in pro le

•

IR

•

TABLE6–8. The Shoulder Shoulder

Position o Part

AP rotational projections

•

Central Ray Directed

Arm extended and 1. supinated, w/ interepicondylar line IR 2. palm against thigh, interepicondylar line 45º to IR 3. elbow slightly exed, back of hand against thigh

•

coracoid process

Structures Included/Best Seen 1. External rotation: true AP humerus, shows greater tubercle in pro le (Fig. 6–15A) 2. Neutral position: good for calci c deposits, trauma, 3. Internal rotation: lateral humerus, shows lesser tubercle in pro le

Note: In case of trauma, the humerus and shoulder must be examined in a neutral position to avoid unnecessary pain and additional injury. Posterior oblique Grashey Method

• • • •

Transthoracic lateral

• • •

PA oblique scapular Y

•

Inferosuperior (non-trauma)

•

•

•

RPO or LPO (erect or recumbent) MSP 35–45º to the a ected side Scapula IR Suspend respiration

•

2″ medial and 2″ inferior to superior and lat shoulder

•

Glenohumeral jt and glenoid cavity (Fig. 6–15B)

Erect lateral A ected surgical neck centered to IR Una ected arm over head

•

A ected surgical neck

•

Lateral shoulder, proximal humerus Projected through thorax

A ected shoulder centered to IR MCP 60º to IR

•

Supine w/ shoulder elevated ≈2″ above tabletop Arm abducted 90º, in external rotation

•

•

shoulder jt

• •

Horizontally to axilla

•

•

Oblique shoulder Especially for demonstration of dislocations (Fig. 6–16) Lat of prox humerus, glenohumeral jt; coracoid process Lesser tubercle in pro le

TABLE6–9. The Clavicle Clavicle

Position o Part

PA or AP

• • •

Recumbent or erect A ected clavicle centered to IR Less OID in PA proj

Central Ray Directed •

midshaft

Structures Included/Best Seen • •

• •

PA or AP axial

•

PA or AP A ected clavicle centered to IR

•

To supraclavicular fossa 15–30º caudad or PA; cephalad or AP

•

Entire length of clavicle Both articulations (Fig. 6–17A) Axial proj of clavicle For fxs not seen in direct PA or AP (Fig. 6–17B)

Note: PA best for optimum detail (less OID); erect PA or recumbent AP usually best for comfort (less discomfort to injured part).

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PART II IMAGING PRO CEDURES

B

A

B

Figure 6–15. (A) Shoulder in external rotation places humerus in a true AP position and places the greater tubercle (J) in pro le. A, shaft of clavicle; B, acromioclavicular joint; C, glenoid cavity; D, lateral/axillary border of scapula; E, scapular spine; F, body of scapula; G, head of humerus; H, coracoid process; I, lesser tubercle; J, greater tubercle; K, surgical neck of humerus; L, shaft of humerus; M, anatomic neck of humerus. (Photo Contributor: Bob Wong, RT.) (B) Posterior oblique (Grashey method) for glenoid cavity. (Photo Contributor: Stamford Hospital, Department of Radiology.)

A B E C

A

D

B

Figure 6–16. PA oblique projection; scapular Y view of the shoulder. Useful for the demonstration of dislocations. Humeral head displaced inferior to coracoid process indicates anterior dislocation, while humeral head displaced inferior to acromion process indicates posterior dislocation. A, acromioclavicular joint; B, acromion process; C, scapular spine; D, medial/vertebral border of scapula; E, coracoid process. (Photo Contributor: Stamford Hospital, Department of Radiology.)

Figure 6–17. (A) AP projection of the fractured clavicle. (B) AP axial projection of the fractured clavicle, better illustrating extent of fracture. (Photo Contributor: Conrad P. Ehrlich, MD.)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

113

TABLE6–10. The Acromioclavicular Joints Acromioclavicular Joints

Position o Part

AP

• •

•

•

Central Ray Directed

AP erect, MSP to mid-IR Arms at sides (bilateral for comparison) Two images in the same position: one w/o and one w/ weights Images must be properly identi ed

•

midline at the level of AC jts

Structures Included/Best Seen • •

AP proj of AC jt and soft tissues Demonstrates dislocation/ separation when performed erect (see Fig. 6–18)

Figure 6–18. Acromioclavicular separation. The examination must be performed erect (in the recumbent position, small separations may not be seen). (Reproduced with permission from Haig SV, Flores CR. Orthopedic Emergencies: ARadiographic Atlas. New York: McGraw-Hill, 2005.)

TABLE6–11. The Scapula Scapula

Position o Part

AP

• •

Lateral (anterior oblique)

Lateral (posterior oblique)

•

• •

•

Central Ray Directed

AP upright or recumbent scapula centered w/ arm abducted, elbow exed

•

Erect PA 45–60º w/ the a ected anterior side toward IR and 1. Arm across chest for acromion and coracoid or 2. Palpate scapular borders and rotate body to superimpose

•

Recumbent oblique A ected posterior surface away from IR Palpate scapular borders and rotate till borders superimposed

•

midscapula, ≈2″ inferior to coracoid process to midvertebral border

Structures Included/Best Seen •

AP scapula with lat portion away from ribs Exposure made during quiet breathing to blur lung markings (see Fig. 6–19A)

•

Lateral scapula

•

1. Acromion and coracoid processes 2. Superimposed vertebral and axillary borders (Fig. 6–19B) to mid axillary border

• • •

Lateral scapula Medial and lateral borders superimposed Humerus away from scapula

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PART II IMAGING PRO CEDURES

A

B

Figure 6–19. (A) AP projection of the scapula. Note that arm abduction moves the scapula away from the rib cage, revealing a greater portion of the scapular body. A, acromion process; B, humeral head; C, glenoid fossa; D, scapular spine; E, clavicle (shaft); F, supraspinatus fossa; G, acromioclavicular articulation; H, scapular notch; I, coracoid process; J, inferior angle/apex of scapula; K, body/ costal surface of scapula; L, axillary/lateral border scapula; M, superior border of scapula. Photo Contributor: Bob Wong, RT. (B) Lateral projection of the scapula. It is taken with the arm elevated and the forearm resting on the head. It demonstrates the scapular body with vertebral and axillary borders exactly superimposed. (Photo Contributor: Stamford Hospital, Department of Radiology.)

Lower Limb and Pelvis

Tarsal Bones

• • • • • • •

Calcaneus/os calsis Talus/astragalus Navicular Cuboid First/medial cuneiform Second/intermediate cuneiform Third/lateral cuneiform

Foot and Toes. T e bones o the oot (Fig. 6–20) include the 7 tarsal bones, 5 metatarsal bones, and 14 phalanges. T e calcaneus (os calsis), or heel bone, is the largest tarsal. It serves as attachment or the Achilles tendon posteriorly, articulates anteriorly with the cuboid bone, presents three articular sur aces superiorly or its articulation with the talus, 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 (talocalcaneal) joint. T e talus also articulates anteriorly with the navicular. 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. T e sinus tarsi (see Figs. 6–28 and 6–31) is part o the subtalar/ talocalcaneal joint, separating its posterior portion rom its anterior and middle portions, and is located on the lateral side o the oot. Sinus tarsi syndrome (S S) is a condition requently associated with an inversion sprain o the ankle with ligament injury resulting in subtalar joint instability. T e sinus tarsi is usually well demonstrated in the medial oblique projection o the oot, and sometimes seen in the lateral projection.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

Navicula r Me dia l cune iform

P ha la nge s C

A

B

Ta lus Ca lca ne us

Me ta ta rs a ls Me dial vie w

D

Figure 6–20. (A) Bones of the foot (dorsal view). (B) Dorsoplantar projection of the foot. (C) Bones of the foot (medial view). (D) Mediolateral projection of the foot. (Photo Contributor: Conrad P. Ehrlich, MD.)

Fractures o the calcaneus can occur, especially as a result o a all rom a height directly onto the heel; these ractures can be comminuted and impacted. T e calcaneus can also be associated with pain ul spur ormation. Stress ( atigue, march) ractures can occur in the metatarsal sha s; x-ray examination can “miss” these ractures until callus appears during bony repair process. Phalangeal ractures are common and usually occur as a result o a stubbing or crushing orce. A common de ormity o the rst metatarsophalangeal joint is hallux valgus. T e rst (great) toe, re erred to as the hallux, slowly adducts (medially), resulting in an in amed rst metatarsophalangeal joint (bunion). T e condition is relieved surgically. T e metatarsals and phalanges o the oot are similar to the metacarpals and phalanges o the hand. T e bases o the ourth and h metatarsals articulate with the cuboid. T e h (most lateral) metatarsal projects laterally and presents a large tuberosity at its base, making it susceptible to racture. Stress ractures are common to the metatarsals. T e hallux has two phalanges; the second through h toes have three phalanges each. T e phalanges o the toes are shorter than those o the ngers. Stubbing- and crushing-type injuries are common causes o ractured phalanges. T e articulations o the oot are named/numbered similarly to those o the hand. Sesamoid bones are small, smooth bones ormed in tendons. In the oot, there are two sesamoid bones located within the exor tendon just

115

116

PART II IMAGING PRO CEDURES

proximal to the rst metatarsophalangeal joint. Sesamoid ractures can occur rom the trauma o repetitive impact associated with activities such as hiking and running, and sports such as tennis and basketball. Ankle. T e ankle joint (mortise) is ormed by the articulation o the talus and distal portions o the tibia and bula (Fig. 6–32). T e medial and lateral malleoli are the most requently ractured components o the ankle joint; severe ractures can disrupt the integrity o the joint and lead to permanent instability and/or arthritis. Foot and/or ankle ractures can occur in alls, twisting injuries, or direct impact as in motor vehicle accidents. Lower Leg. T e tibia and bula (Fig. 6–21) compose the bones o the lower leg. T e tibia is larger and is situated medially. It articulates superiorly with the emur and in eriorly with the talus, orming a portion o the ankle joint. T e tibia consists o a sha /body and two expanded extremities. Its distal extremity has a prominence, the medial malleolus, which also participates in the ormation o the ankle mortise. T e bular notch provides articulation or the bula to orm the distal tibio bular joint. La te ra l condyle

Inte rcondyla r e mine nce

S tyloid of fibula Me dia l condyle

He a d of fibula

S upe rior tibiofibula r joint

Tibia l tube ros ity

S ha ft of tibia S ha ft of fibula

Me dia l ma lle olus

Infe rior tibiofibula r joint

Mortis e of a nkle joint La te ra l ma lle olus Ante rio r

Po s te rio r

Figure 6–21. Right lower leg, tibia and bula.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

T e proximal end o the tibia presents a medial and a lateral condyle, on whose superior sur aces there are acets or articulation with the emur. T e articular acets orm a smooth sur ace called the tibial plateau, which provides attachment or the cartilaginous menisci o the knee joint. Between the two articular sur aces is a raised prominence, the intercondylar eminence (tibial spine). T e proximal anterior sur ace o the tibia presents the tibial tuberosity, which provides attachment or the patellar ligament. Osgood–Schlatter disease is a chronic epiphysitis o the tibial tuberosity that occurs in some active young adults. Not really a disease, it is an overuse condition that results rom repetitive impact trauma such as occurs in jumping and kicking activities. Its symptoms include pain and tenderness at the tibial tuberosity, and it is mani ested radiographically by bony separation at the epiphysis. T e bula is the slender, lateral non–weight-bearing bone orming the lower leg; it also consists o a sha /body and two expanded extremities. T e bulbous distal end is the lateral malleolus (projects more distally than the medial), which helps orm the ankle joint and has a acet or articulation with the tibia (distal tibio bular joint). T e expanded proximal portion o the bula is the head, which articulates with the lateral tibial condyle, orming the proximal tibio bular joint. A styloid process extends superiorly rom the head o the bula. T e neck is the constricted portion just distal to the bular head. T e bula is most commonly ractured at the malleolus, just above the ankle joint. Knee. T e knee is ormed by three bones—the proximal tibia, the patella, and the distal emur (Figs. 6–22, 6–23)—which articulate to orm two joints, the emorotibial (hinge joint) and emoropatellar (gliding joint).

Figure 6–22. AP knee.

117

118

PART II IMAGING PRO CEDURES

La te ra l fe mora l condyle

La te ra l me nis cus

Fe mora l pa te lla r s urfa ce

Pos te rior crucia te liga me nt Me dia l fe mora l condyle

C A

Ante rior crucia te liga me nt

D

Me dia l me nis cus

La te ra l colla te ra l liga me nt

A

B

Tra ns ve rs e ge nicula r liga me nt Me dia l colla te ra l liga me nt B

Figure 6–23. (A) Ligaments of the knee joint. (B) The knee should be exed no more than 10° when transverse fracture of patella is known or suspected; exion can cause pain, fragment separation, and/or complication. The CR can be angled 5° cephalad to superimpose the magni ed medial femoral condyle on the lateral condyle to permit better visualization of the joint space; angulation was not employed in this projection and the joint space is obscured by the magni ed medial femoral condyle. A, medial femoral condyle; B, tibial tuberosity; C, tibial plateau; D, head of bula. (Photo Contributor: Stamford Hospital, Department of Radiology.)

T e distal posterior emur presents two large medial and lateral condyles separated by the deep intercondyloid ossa. wo small prominences, the medial and lateral epicondyles, are superior to the condyles. T e emoral and tibial condyles articulate to orm the emorotibial joint. Semilunar cartilages, the menisci, lie medially and laterally between these articulating bones and, together with the cruciate and collateral ligaments, help orm the articular capsule o the knee (Fig. 6–23A). T e patella is a triangular bone with its base superior and apex in erior. T e patella is the largest sesamoid bone and is attached to the tibial tuberosity by the patellar ligament and glides over the patellar sur ace o the distal emur ( emoropatellar joint) during exion and extension o the knee. Simple patellar ractures are usually transverse (Fig. 6–23B). Fractures o the patella can also be stellate or comminuted. Patellar ractures can require surgical internal xation via gure-o -eight or tension band wiring; more complex ractures can require partial patellectomy. T e congenital anomaly, bipartite or multipartite patella, can be misinterpreted as a racture. Bipartite and multipartite patellae occur in a very small percentage o the population (about 1%) and are usually asymptomatic. Just opposite the patellar sur ace, on the posterior distal

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

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

Me dia l condyle

La te ra l condyle

Po s te rio r

Figure 6–24. The right femur.

emur, is the smooth popliteal sur ace, which accommodates the popliteal artery. Femur. T e emur (Fig. 6–24) is the longest and strongest bone in the body. T e emoral sha /body is bowed slightly anteriorly. T e proximal end o the emur consists o a head, which is received by the acetabulum o the pelvis. T e emoral head has a small notch, the ovea capitis emoris, or ligament attachment. T e ligament o the emoral head, or ligamentum teres, connects the ovea capitis emoris to the acetabulum. T e emoral neck, which joins the head and sha , angles upward approximately 120° and orward (in anteversion) approximately 15°. T e greater (lateral) and lesser (medial) trochanters are large processes on the posterior proximal emur. T e greater trochanter is a prominent positioning landmark that lies in the same transverse plane as the pubic symphysis and coccyx. T e (posterior) intertrochanteric crest runs obliquely between the trochanters; the (anterior) intertrochanteric line runs anteriorly parallel to the crest. T e emoral sha presents a long narrow ridge posteriorly called the linea aspera. Its distal anterior portion presents the patellar sur ace—a triangular depression over which the patella glides during exion and extension motions.

Articulation Summary: Lower Limb and Pelvic Girdle

• • • • • •

Sacroiliac

• • • •

Intertarsal

Hip (femoral head w/ acetabulum) Knee (femorotibial) Proximal tibio bular Distal tibio bular Ankle (distal tibia and bula w/ superior talus) Tarsometatarsal Metatarsophalangeal Interphalangeal

119

120

PART II IMAGING PRO CEDURES

A B K

C D

J

G

I

E

H F

Figure 6–25. AP projection of the left hip. Leg is internally rotated, placing femoral neck parallel to the IR. A, sacroiliac joint; B, anterior inferior iliac spine; C, femoral head; D, greater trochanter; E, intertrochanteric crest; F, lesser trochanter; G, femoral neck; H, ischial tuberosity; I, obturator foramen; J, pubis; K, greater sciatic notch. (Photo Contributor: Stamford Hospital, Department of Radiology.)

Hip Fracture Classi cations

•

Subcapital: common, inferior to femoral head

• • •

Transcervical: across the femoral neck Basicervical: at the base of the femoral neck Intertrochanteric: common, between the trochanters

T e distal posterior sur ace presents the popliteal sur ace—a depression that houses the popliteal artery. T e medial and lateral emoral condyles are very prominent posterior structures, and between them is the deep intercondyloid ossa. Just above the condyles are the medial and lateral emoral epicondyles. T e articulation o the emoral head with the pelvic acetabulum orms the hip joint. T e emoral neck (Figs. 6–24 and 6–25) is the most commonly ractured portion o the emur. In young people, hip ractures are most o en a result o high impact and/or high velocity trauma. In the elderly, they are most o en the result o a all. Fractures o the emoral sha are usually the result o a direct blow; racture displacement is dependent on muscular pull and traumatic impact. Dislocations o the hip joint are airly uncommon because o the very strong pelvic and hip musculature. Disturbance o the ovea capitis emoris or disruption o the nutrient arteries supplying the emoral neck can result in avascular necrosis o the emoral head. Pelvis. Pelvis, the Latin word or “basin,” was originally named or its shape. T e pelvic girdle consists o two innominate (hip or coxal) bones,

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

Sacrum

Iliac crest Sacroiliac joint

ASIS Anteroinferior iliac spine

Ilium Pubis Ischium

Ischial spine

Coxa

Acetabulum Obturator foramen Coccyx

Pubic tubercle Pubic symphysis Ischial tuberosity

A

Iliac crest

Ilium

Sacrum

Posterosuperior iliac spine Posteroinferior iliac spine

Greater sciatic notch Ischial spine

Sacral hiatus

Coccyx

Symphysis pubica

Lesser sciatic notch Obturator foramen

Ischiopubic ramus Ischial tuberosity

B

Ilium Posterosuperior spine Posteroinferior spine Greater sciatic notch Spine of ischium Lesser sciatic notch Ischium

Crest of ilium

Anterosuperior spine Anteroinferior spine Acetabulum Obturator foramen Pubic tubercle Pubis Inferior ramus of pubis

Ischial tuberosity Inferior ramus of ischium C

Figure 6–26. (A) The pelvis (anterior view). (B) The pelvic girdle (posterior view). (C) The right hip bone (lateral view), showing the acetabulum. (continued )

121

122

PART II IMAGING PRO CEDURES

R

D

Figure 6–26. (Continued ) (D) AP projection of the pelvis. The femoral necks are seen in their entirety: internal rotation of the feet/legs places them parallel to the IR. Note fractures of the public and ischial rami on the left. (Photo Contributor: Stamford Hospital, Department of Radiology.)

one on each side o the sacrum. Each innominate bone consists o three used bones: the ilium, ischium, and pubis (Fig. 6–26). Parts o these three bones contribute to the ormation o the acetabulum (Latin word or “little vinegar cup”)—the socket articulation or the emoral head. T e labrum is a ring o brocartilage along the outer rim o the acetabulum which acts like a suction cup, deepening the acetabulum and increasing contact between the articular sur aces o the acetabulum and emoral head. Any tear or other injury to the labrum causes hip or groin pain, sti ness, clicking, or “catching” sensation. Labral injuries can be degenerative or traumatic. T e ilia are the large, superior bones whose medial auricular sur aces orm the sacroiliac joints bilaterally. T e broad, at portion o each ilium is the ala, or wing; the upper part o the ala orms a ridge o bone called the iliac crest, which terminates in anterior and posterior iliac spines. T e arcuate line o the ilium is a smooth rounded border on the internal sur ace o the ilium. It is immediately in erior to the iliac ossa. T e ischium orms the posteroin erior portion o the pelvis. T e posterior part o the ischium orms the major portion o the greater and lesser sciatic notches separated by the ischial spine. T e most in erior portion is the ischial tuberosity—a large, rough prominence that provides attachment or posterior thigh muscles. T e in erior ramus o the ischium extends medially rom the tuberosities to unite with the in erior ramus o the pubis. T e pubic bones orm the anterior portion o the pelvis. T eir bodies unite to orm the pubic symphysis; just lateral to each superior margin o the symphysis are the prominent pubic tubercles. T e superior pubic ramus uses with the ilium and in erior pubic ramus with the ischium to

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

orm the large obturator oramen. T e pectineal line o the pubis is a ridge on the superior rami o the pubic bones. In combination with the arcuate line, it comprises the iliopectineal line. T e superior circum erence o the lesser pelvis orms the brim o the pelvis, or the pelvic inlet. T e edge o the inlet is known as the pelvic brim. T e terms are o en used interchangeably. Most pelvic ractures are result o trauma (MVA, alls, sports injuries) and carry a signi cant risk o serious pelvic bleeding. Pelvic ractures can cause disturbance o the urinary bladder or urethra; an intravenous urogram (IVU) or abdominopelvic C may be required to diagnose any urinary leakage. T e normal emale (gynecoid) pelvis di ers rom the normal male (android) pelvis in that it is shallower and its bones are generally more delicate. T e pelvic outlet is wider and more circular in the emale; the ischial tuberosities and acetabula are urther apart; and the angle ormed by the pubic arch is also greater in the emale. All these bony characteristics acilitate the birth process (Fig. 6–27).

C

Normal Male/Android Pelvis

• • • •

Narrower, more vertical

• • • • •

Normal female/gynecoid pelvis

Deeper from anterior to posterior Pubic angle less than 90° Pelvic inlet narrower and heart-shaped/ round Wider, more angled toward horizontal Shallower from anterior to posterior Pubic angle greater than 90° Pelvic inlet larger and rounder

90°

100°

or le s s

or more

A

123

B

D

Figure 6–27. Architectural di erences in the (A) male and (B) female pelves. (C) AP projection of the male pelvis. (D) AP projection of the female pelvis. Femoral necks are parallel to the IR and greater trochanters are seen in pro le. (Photo Contributor: Stamford Hospital, Department of Radiology.)

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Positioning. Positioning o the lower limb and pelvis requires a thorough knowledge o the skeletal anatomy—and an awareness o possible pathologic conditions and their impact on positioning and technical actors. Clothing having radiopaque objects such as buttons, snaps, or zippers should be removed i possible. Bulky or bunched clothing can produce undesirable radiographic arti acts and should there ore be removed whenever possible and replaced with a hospital dressing gown. Elastic waist garments can contribute to nonuni orm density on abdominal radiographs. T e patient must be instructed about the importance o remaining still, and immobilization devices such as radioparent sponges and sandbags should be used as required. T e shortest possible exposure time should be employed, especially when involuntary motion is a potential problem. Many lower limb examinations can be per ormed tabletop (i.e., nonBucky); the knee requently requires a grid; and emur, hip, and pelvis almost always do. Suspended respiration is suggested or radiography o the proximal portion o the lower limb and the pelvis. Patients must always be appropriately shielded. Some o the lower leg projections can be per ormed in either AP or PA position, depending on the condition and com ort o the patient. Lateral projections can be easily obtained using a horizontal (cross-table lateral) beam when limb or patient movement is contraindicated. ables 6–12 through 6–23 provide a summary o routine and requently per ormed special positions/projections o the lower limb and pelvis. Long Bone Measurement. Accurate measurement o long bones, usually the lower limbs, is occasionally required to evaluate abnormal growth patterns in children or lower back disorders in adults (see able 6–24). Gait abnormalities are requently associated with leg length inequality and can lead to degenerative arthritis o the lumbar spine and/or lower limb. TABLE6–12. The Foot Foot

Position o Part

Dorsoplantar (AP)

• •

Knee exed ≈45º Plantar surface on IR

Central Ray Directed •

or 10º toward heel to base of the third metatarsal

Structures Included/Best Seen •

•

Frontal proj of tarsals (except calcaneus and part of talus) Frontal proj of metatarsals, phalanges and their articulations

Note: A 10° posterior angulation may be used to better demonstrate jt spaces. Medial Oblique

• • •

Start as dorsoplantar Rotate medially 30º Plantar surface and IR are 30º

•

base of the third metatarsal

•

•

Most tarsals and metatarsals (except the most medial), their articulations Sinus tarsi, tuberosity of fth metatarsal (see Fig. 6–28)

Note: Lateral oblique foot demonstrates interspaces b/w the rst and second metatarsals and b/w the rst and second cuneiforms. Lateral (mediolateral or lateromedial)

• • • •

Recumbent lateral Patella tabletop Foot slightly dorsi exed Plantar surface IR

•

metatarsal bases

• •

Lateral foot, ankle jt, dist tibia and bula Superimposed tarsals, tibia, and bula (see Fig. 6–29)

Note: The lateral projection is more accurately obtained in the lateromedial (rather than mediolateral) position. Note: Lateral weight-bearing eet are occasionally requested to demonstrate the status of the plantar arches.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

E F

G A H

B

I

C

D

J

Figure 6–28. Medial oblique view of the left foot, demonstrating the articulations of the cuboid with the calcaneus, fourth and fth metatarsals, and lateral cuneiform. The talonavicular articulation and sinus tarsi are also demonstrated. A, lateral/third cuneiform; B, navicular; C, talus/astragalus; D, sinus tarsi; E, third metatarsophalangeal joint; F, head of the fourth metatarsal; G, base of the fourth metatarsal; H, base/tuberosity of the fourth metatarsal; I, cuboid; J, calcaneus/os calsis. (Photo Contributor: Stamford Hospital, Department of Radiology.)

A

B

D

E

C

Figure 6–29. Lateral projection of the foot, demonstrating superimposed tarsals, metatarsals, and phalanges; a little more of the distal tibia and bula should be visualized. A, talus/astragalus; B, calcaneus/os calsis; C, cuboid; D, navicular; E, medial/ rst cuneiform. (Photo Contributor: Stamford Hospital, Department of Radiology.)

125

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PART II IMAGING PRO CEDURES

TABLE6–13. The Toes Toes

Position o Part

Dorsoplantar (AP)

• •

Medial Oblique

• •

Lateral

•

•

Sesamoids (tangential)

• •

Central Ray Directed

Knee exed ≈45º Plantar surface on IR

•

Start as dorsoplantar Rotate medially 30–45º

•

Turn to side that brings a ected toe(s) closest to IR Una ected toes may be taped back

•

Prone, oot dorsi exed 15–20º Toes dorsi exed 15–20º, resting on IR

•

or 10º toward heel, to second MTP

Structures Included/Best Seen •

Phalanges, their articulations, dist metatarsals in frontal proj (usually entire foot examined in this position)

3rd MTP

•

Oblique proj of phalanges, their articulations, dist metatarsals

proximal IPJ

•

Lateral proj of toe(s) and associated articulations

•

Sesamoids in pro le, free of superimposition

or ≈10° caudad to IR to rst MTP

TABLE6–14. The Calcaneus Calcaneus (Os Calcis)

Position o Part

Plantodorsal Axial

• • •

Dorsoplantar Axial

• •

Lateral

• • •

Central Ray Directed

Seated on table with leg extended Plantar surface tabletop Immobilize w/ strip of tape/gauze held by patient

•

Prone, plantar surface tabletop IR placed against plantar surface

•

Recumbent on the a ected side Patella tabletop Foot and ankle lateral

•

Figure 6–30. Plantodorsal projection of calcaneus; sustentaculum tali, trochlear process, and calcaneal tuberosity are well visualized. (Photo Contributor: Stamford Hospital, Department of Radiology.)

Structures Included/Best Seen

40º cephalad to base of the third metatarsal

•

40º caudally to the level of base of second

•

mid-calcaneus

•

•

•

Axial proj of calcaneus Includes trochlear process, sustentaculum tali, talocalcaneal jt (see Fig. 6–30) Axial proj of calcaneus Includes trochlear process, sustentaculum tali, talocalcaneal jt Lateral calcaneus, talus, navicular, ankle jt, and sinus tarsi (see Fig. 6–31)

Figure 6–31. Lateral calcaneus; sinus tarsi is well visualized. (Photo Contributor: Stamford Hospital, Department of Radiology.)

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127

TABLE6–15. The Ankle Ankle

Position o Part

AP

• •

AP mortise; medial obl

• • •

Central Ray Directed

Leg extended AP Plantar surface IR

•

Leg extended AP Rotated 15–20º medially intermalleolar plane IR

•

midway b/w malleoli through tibiotalar jt midway b/w malleoli, intermalleolar plane

Structures Included/Best Seen •

AP ankle jt, dist tibia/ bula, talus (see Fig. 6–32A)

•

AP ankle mortise Talotibial, talo bular jts well seen All three aspects of mortise jt seen in pro le (see Fig. 6–32B)

• •

Note: A 45° medial oblique is often used in ankle surveys. It demonstrates the distal tibia and bula with perhaps some superimposition on the talus. Lateral (mediolateral or lateromedial)

• • •

Recumbent on the a ected side Patella tabletop Foot dorsi exed (≈90º)

•

ankle jt

• •

Lateral dist tibia/ bula, ankle jt Lateral talus, calcaneus, navicular

Note: The lateral projection is more accurately obtained in the lateromedial (rather than mediolateral) position. AP stress views

• • •

Leg extended, ankle true AP Foot dorsi exed Plantar surface • One exposure w/ jt in stressed inversion • One exposure w/ jt in stressed eversion

•

midway b/w malleoli

• •

AP ankle jt in inversion and eversion Evaluates jt separation, ligament tear

Note: If someone (e.g., the MD) must hold the ankle in position for the stress views, be certain that appropriate radiation precautions are taken.

L

A

L

B

Figure 6–32. (A) AP projection of the ankle joint. (Photo Contributor: Stamford Hospital, Department of Radiology.) (B) The 15 to 20° medial oblique projection of the ankle is used to demonstrate the ankle mortise. An oblique projection of the distal tibia/ bula, proximal talus, and their articular surfaces is also demonstrated. (Photo Contributor: Stamford Hospital, Department of Radiology.)

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TABLE6–16. The Lower Leg (Tibia/Fibula) Lower Leg (Tibia /Fibula )

Position o Part

AP

• • •

Lateral

• • •

AP Oblique (medial and lat rotation)

• •

Central Ray Directed

Leg extended AP No pelvic rotation Foot dorsi exed

•

Recumbent on the a ected side Patella tabletop Ankle and foot lat

•

Leg extended w/ foot dorsi exed Leg rotated 45º medially or laterally

•

Structures Included/Best Seen

midshaft tibia

• •

A

midshaft

• •

midshaft tibia

•

AP lower leg Both jts included (Fig. 6–33A) Lat tibia/ bula Both jts included (Fig. 6–33B) Medial rotation shows proximal and dist tibio bular articulations

B

Figure 6–33. Demonstrates fractures and their degree of displacement. (A) AP projection of the tibia and bula. (B) Lateral projection of the tibia and bula. Both joints should be included whenever possible. These images demonstrate how AP/PA projections demonstrate medial/lateral relationships and how lateral projections demonstrate anterior/posterior relationships. (Photo Contributor: Stamford Hospital, Department of Radiology.)

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129

TABLE6–17. The Knee Knee

Position o Part

AP

• • •

Lateral

• • •

Central Ray Directed

Leg extended AP No pelvic rotation Leg may be rotated 3–5º internally

•

Recumbent on a ected side Patella tabletop Knee exed 20–30º

•

•

Structures Included/Best Seen

To 1/2″ below patellar apex (knee jt) Direction of CR depends on distance b/w ASIS and tabletop: • Up to 19 cm (thin pelvis) 3–5º caudad • 19–24 cm 0º CR • > 24 cm (thick pelvis) 3–5º cephalad

•

5º cephalad to knee jt

•

•

• •

AP weight bearing (bilateral)

• •

AP erect against upright Bucky Weight evenly shared on legs

•

CR midway b/w knees at the level of patellar apices

• •

AP knee jt, dist femur, and proximal tibia/ bula Patella seen through femur

Lat proj of the knee and femoropatellar jts Superimposed femoral condyles knee should not be exed > 10º with known or suspected patellar x (see Fig. 6–23B) AP weight-bearing knee jts Particularly useful for evaluation of arthritic conditions (see Fig. 6–40C)

Note: If the oblique projections of the knee are requested, they are performed using a 45° oblique. The proximal tibio bular articulation is best demonstrated in a 45º internal/medial oblique knee position. Intercondyloid fossa (Camp Coventry/PA axial)

•

Intercondyloid fossa (Bècleré )

•

•

•

•

PA recumbent Knee exed so tibia forms 40º w/ tabletop Foot resting on support

•

AP w/ knee exed ≈20–30º Resting on supported IR

•

CR 40º caudad ( long axis of tibia) to knee jt

• •

•

CR cephalad ( long axis of tibia) to knee jt

• •

PAaxial (superoinferior) proj Shows intercondyloid fossa, tibial plateau, and eminences “Tunnel view” (see Fig. 6–34A and B) AP axial (inferosuperior) proj Shows intercondyloid fossa, tibial plateau, and eminences; “tunnel view”

Note: The Holmblad PA axial method of intercondyloid fossa is performed in a kneeling position. The a ected knee is centered, and CR forms a 20º angle w/ femur.

CR

A

90

°

B

Figure 6–34. (A) Intercondyloid fossa, using the Camp–Coventry method. The tibial plateau and eminences are well visualized. (Photo Contributor: Stamford Hospital, Department of Radiology.) (B) Patient and CR positioning for Camp–Coventry method.

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PART II IMAGING PRO CEDURES

Figure 6–35. Tangential “sunrise”(Settegast) projection of the patella. The femoropatellar joint is well demonstrated. (Photo Contributor: Stamford Hospital, Department of Radiology.)

TABLE6–18. The Patella Patella

Position o Part

PA

• •

Lateral (mediolateral)

• • •

Tangential (Settegast/ prone exion 90º)

•

•

Central Ray Directed

Prone position Leg rotated ≈5–10º laterally to place patella tabletop

•

Recumbent on a ected side Patella tabletop Knee exed only 5–10º

•

Prone (or seated) on x-ray table Knee exed at least 90º

•

Structures Included/Best Seen

patella (enters popliteal region)

•

IR and midfemoropatellar jt

•

Directed to midfemoropatellar jt

•

•

•

• •

Tangential (Hughston/ prone exion 55º)

•

•

Prone (or seated) on x-ray table Knee exed ≈55º

•

Directed to midfemoropatellar jt

• •

•

PA patella, including knee jt Better detail than the AP position (less OID) Lat proj Patella and femoropatellar jt Tangential proj of the patella, femoropatellar articulation Useful for demonstrating vertical fx Must not be attempted in known or suspected transverse fx of patella Tangential proj of the patella (Fig. 6–35) Femoropatellar articulation— demonstrates vertical fx Must not be attempted in known or suspected transverse patellar fx

Note: It has been suggested that the Settegast and Hughston methods be modi ed to lesser degrees o exion, in order that the patella not be pulled into the femoropatellar groove. Note: The tangential projection/Merchant method of demonstrating the patella and femoropatellar jts can require the use of special equipment. However, the essential components of the method include relaxed quadriceps muscles, ≈45° knee exion, ≈30º caudal CR angle, at a 6-feet SID to reduce magni cation.

TABLE6–19. The Femur Femur

Position o Part

AP

•

•

Lateral (mediolateral)

•

•

Central Ray Directed

Supine, a ected femur centered to grid Leg internally rotated 15º

•

Recumbent lateral w/ the a ected leg centered to grid Patella tabletop

•

midfemoral shaft (to include hip and possibly knee jt) midshaft

Structures Included/Best Seen • •

• •

AP proj of the femur, including hip jt Leg rotation overcomes anteversion of femoral neck and places neck IR Lateral proj of the femur, from knee jt up May be performed w/ horizontal beam if suspected fx or pathologic disease

Note: If an orthopedic appliance is present, the x-ray image should include the entire appliance and the articulation closest to it.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

131

TABLE6–20. The Hip Hip

Position o Part

AP

•

• •

Supine, sagittal plane 2″ medial to ASIS centered to grid No pelvic rotation Leg rotated 15º internally

Central Ray Directed •

Sagittal plane 2″ medial to ASIS at level of greater trochanter

Structures Included/Best Seen •

•

•

AP hip jt, femoral neck and proximal femur A portion of the pelvic bones is included The greater trochanter should be seen in pro le

Note: Another method of hip localization is to bisect the ASIS and pubic symphysis: this is the peak of the femoral head. A point ≈2.5″ dist and is the midpoint of the femoral neck (see Fig. 6–25). Note: Leg inversion must never be orced and is contraindicated in cases o known or suspected x or destructive disease. AP oblique (unilateral rog-leg, nontrauma; modi ed Cleaves)

•

• •

Supine, ASIS of a ected side centered to grid Knee and hip acutely exed Thigh(s) abducted 40º

•

the a ected hip at a level 1″ above the pubic symphysis

• •

AP oblique proj of the hip jt Lesser trochanter should be seen on the medial aspect of the femur (see Fig. 6–36)

Note: Bilateral examination can be performed by positioning both hips and directing the CR to the MSP at a point 1″ above the pubic symphysis. Note: The above position must not be attempted when fx is suspected. Axiolateral inferosuperior (cross-table lateral; Danelius-Miller)

• • •

Supine, una ected leg elevated Leg rotated internally 15º Grid placed against thigh to femoral neck

•

femoral neck and grid

•

•

Lateral proj of the proximal femur and its articulation with the acetabulum The lesser trochanter will be prominently seen on the posterior aspect of the femur

Note: Leg inversion must never be forced and is contraindicated in cases of known or suspected fx or destructive disease. This position requires localization of the long axis of the femoral neck. First, note the midpoint b/w the ASIS and pubic symphysis of a ected side; next, note a point 19 dist to the prominence of the greater trochanter. A line b/w these two points parallels the long axis of the femoral neck. Trauma axiolateral inferosuperior, trauma (ClementsNakayama)

•

Acetabulum posterior obl. (Judet)

•

•

•

•

Supine, legs extended A ected side to edge of table (Bucky side) Cassette placed on extended Bucky tray, and tilted back ≈15–20º, CR

•

CR angled 15–20º posteriorly, entering proximal medial thigh, mid-femoral neck

•

Lateral oblique of proximal femur, hip jt

Semisupine recumbent 45º post obl

•

If a ected side down, CR 2″ medial and dist to (down side) ASIS If a ected side up, CR 2″ dist to (upside) ASIS

•

Downside shows anterior rim of acetabulum

•

Upside shows posterior rim and obturator foramen

•

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PART II IMAGING PRO CEDURES

Figure 6–36. AP oblique (modi ed Cleaves) view of the hip. The femoral neck and greater and lesser trochanters are well de ned; the lesser trochanter is seen medially.

Figure 6–37. AP projection of the pelvis. The femoral necks are seen in their entirety: internal rotation of the feet/legs places them parallel to the IR. Note fractures of the public and ischial rami on the left. (Photo Contributor: Stamford Hospital, Department of Radiology.)

TABLE6–21. The Pelvis Pelvis

Position o Part

AP

• • •

Pelvic bones outlet/inlet projections

• •

Central Ray Directed

Supine, MSP tabletop No pelvic rotation Legs rotated internally 15º

•

Supine No pelvic rotation

•

•

Structures Included/Best Seen

midline at a level 2″ above greater trochanter; top of IR 1–2″ above iliac crest

•

Outlet: CR to pubic symphysis/greater trochanter at 20–35° cephalad (males), 30–45° cephalad (females) Intlet: CR 40° caudad, entering m/w b/w ASISs

•

Outlet: shows ischial body and ramus, pubic superior and inferior rami

•

Inlet: shows entire (upper) pelvic unlet

•

AP proj of the pelvis and upper femora Femoral necks, greater trochanters free of superimposition (Fig. 6–37)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

133

TABLE6–22. The Ilium Ilium

Position o Part

AP

• •

•

Central Ray Directed

Supine Sagittal plane passing through hip jt of the a ected side centered to grid Obliqued 40º toward the a ected side

Structures Included/Best Seen

, enters the sagittal plane 2″ medial to ASIS at level m/w b/w crest and greater trochanter

•

• •

AP proj of the ilium Part obliquity “opens” the ilium by placing it to the IR

TABLE6–23. The Sacroiliac Joints Sacroiliac Jts

Position o Part

AP axial

• •

AP oblique (LPO and RPO)

• • •

PA oblique (LAO and RAO)

• •

•

A

Central Ray Directed

Supine MSP centered to grid

•

Supine Obliqued 25–30º af ected side up Sagittal plane passing 1″ medial to ASIS centered to grid

•

Prone Obliqued 25–30º af ected side down Sagittal plane passing 1″ medial to ASIS centered to grid

•

30–35º cephalad, to the midline approximately 2″ below level of ASIS a point 1″ medial to ASIS

Structures Included/Best Seen •

Sacrum, SI joints, and L5–S1 articulation

•

SI jt of the elevated side Opposite obl is similarly obtained SI jt is placed IR (Fig. 6–38A and B)

• •

a point 1″ medial to ASIS

• • •

SI jt of the “down” side Opposite obl is similarly obtained SI jt is placed IR

B

Figure 6–38. (A) AP right SI joint with perpendicular CR. (B) LPO right SI joint with perpendicular CR; 25° obliquity opens SI joint nicely. (Photo Contributor: Conrad P. Ehrlich, MD.)

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PART II IMAGING PRO CEDURES

TABLE6–24. Long-Bone Measurement Long Bone Measurement

Position o Part

AP (leg)

• • • •

Central Ray Directed

Supine Leg extended and centered to grid Metal ruler taped alongside One exposure each at hip, knee, and ankle jts (on one IR)

hip, knee, ankle

•

Structures Included/Best Seen •

jts •

Tightly collimated AP proj of hip, knee, and ankle jts With (metallic) ruler alongside

Note: For bilateral examination, ruler is placed b/w legs, there must be no rotation, and if one knee is somewhat exed, the other must be identically exed for the exposure.

To Locate Joints

•

Hip: Bisect the ASIS and pubic symphysis; center 1″ distal and lateral to that point

•

Knee: Center immediately below the patellar apex

•

Ankle: Center midway between the malleoli

A

Arthrography. Arthrography is a contrast examination per ormed to evaluate so -tissue joint structures, such as articular cartilages, menisci, ligaments, and bursae. It can be per ormed using conventional or digital uoroscopic imaging or, as in most cases today, MR or C imaging can replace or supplement the original conventional uoroscopic imaging. T e conventional x-ray examination is/was most o en per ormed as double contrast, with a positive contrast agent (water-soluble iodinated) coating the structures and a negative contrast agent (air) lling the joint cavity. Fluoroscopic images are made during the examination while applying various stress maneuvers. Overhead radiographs could be requested as supplemental images. In MR or C arthrography, using uoroscopy, contrast media is introduced into the joint space. T e MR contrast medium is typically gadolinium, while the C contrast medium is generally a water-soluble iodinated medium. Knee manipulation and uoroscopic images can be made be ore the patient is escorted to the MR or C department or urther imaging. T e knee is the most common joint to be examined in this way, although the hip, wrist, shoulder (Fig. 6–39A), and temporomandibular joint ( MJ) can also be evaluated with contrast arthrography.

B

Figure 6–39. (A) A shoulder arthrogram. (B) MR imaging of the shoulder is accomplished noninvasively and provides visualization of structures having subtle di erences in tissue density. (Photo Contributor: Stamford Hospital, Department of Radiology.)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

135

Terminology and Pathology. Some o the radiologically signi cant skeletal disorders or conditions o upper and lower limbs with which the student radiographer should be amiliar are listed as ollows: • • • • • • •

Acromegaly Battered child syndrome Bone metastases Bursitis Carpal tunnel syndrome Epicondylitis Fracture (Figs. 6–17, 6–23, 6–33, and 6–42) • Gout • Osgood–Schlatter disease • Osteoarthritis (Fig. 6–40B)

• • • • • • •

Osteochondroma Osteomalacia Osteomyelitis Osteoporosis Paget disease (Fig. 6–40A) Rickets Slipped emoral capital epiphysis • Subluxation • alipes • endonitis

Types of Fractures (Fig. 6–41) • • • • • • • •

• • • • • • • • •

Simple: an undisplaced racture ( x) (Fig. 6–41A) Displaced: ractured ends o bone are out o alignment (Fig. 6–41B) Compound: ractured end o bone has penetrated skin (open x) Incomplete: x does not traverse entire bone; little or no displacement Greenstick: break o cortex on one side o bone only; ound in in ants and children (Fig. 6–41D) orus/buckle (see Fig. 6–42): greenstick x with one cortex buckled/ compacted and the other intact Stress/ atigue: response to repeated strong, power ul orce (e.g., jogging, marching) Avulsion: small bony ragment pulled rom bony prominence as a result o orce ul pull o the attached ligament or tendon (chip racture) Hairline: aint undisplaced x Comminuted: one racture composed o several ragments (Fig. 6–41C) Butter y: comminuted x with one or more wedge or butter y wing– shaped pieces Spiral: long x encircling a sha ; result o torsion (twisting orce); especially lower leg (distal tibia and proximal bula) Oblique: longitudinal x orming an angle (approximately 45°) with the long axis o the sha ransverse: x occurring at right angles to long axis o bone Boxer: x neck o ourth or h metacarpal (Fig. 6–3C) Monteggia: x proximal third o ulnar sha with anterior dislocation o radial head Colles: transverse racture o distal third o radius with posterior angulation and associated avulsion x o ulnar styloid process (Fig. 6–4B)

Some Conditions Requiring Adjustment in Exposure Decrease in Exposure Factors

Increase in Exposure Factors

Arthritis Ewing sarcoma Osteomalacia Osteoporosis Rickets Thalassemia

Acromegaly Chronic gout Multiple myeloma Osteochondroma Osteopetrosis Paget disease (osteitis deformans)

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PART II IMAGING PRO CEDURES

A

A

B D C E

F

B

C

Figure 6–40. A. AP projection of the hip and proximal femur demonstrates Paget disease. Early lytic changes are seen throughout the bone; observe the beginning of typical “cotton wool”appearance in the region of the head and trochanters. The hip is well positioned, the femoral neck is parallel to the image receptor (not foreshortened), and the greater trochanter is seen in pro le. (Photo Contributor: Stamford Hospital, Department of Radiology.) (B) AP knee joint, recumbent. (C) The same knee joint taken weight bearing. Note demonstration of signi cant joint narrowing. A, medial femoral epicondyle; B, medial femoral condyle; C, tibial plateau; D, medial intercondylar tubercle/tibial intercondylar eminence; E, lateral tibial condyle; F, head of bula. (Reproduced with permission from Miller TT, Schweitzer ME. Diagnostic Musculoskeletal Imaging. New York: McGraw-Hill, 2005.)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

137

•

rimalleolar: x lateral malleolus, x medial malleolus on medial and posterior sur aces • Jones: x base o h metatarsal • Potts: x distal tibia and bula with dislocation o ankle joint • Pathologic: x o bone weakened by pathologic condition, or example, metastatic bone disease

A. No ndis plac e d

C. Co mminute d

B. Dis plac e d

D. Gre e ns tick

Figure 6–41. (A) Nondisplaced fracture, (B) displaced fracture, (C) comminuted fracture, and (D) greenstick fracture. (From Saladin K. Anatomy and Physiology: The Unity o Form and Function. 7th ed. New York, NY: McGraw-Hill Education.)

Figure 6–42. Torus/buckle-type greenstick fracture. (Reproduced with permission from Simon RS, Koenigsknecht SJ. Emergency Orthopedics: The Extremities, 3rd ed. East Norwalk, CT: Appleton & Lange, 1995.)

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COMPREHENSION CHECK Congratulations! You have completed a large portion of this chapter. If you are able to answer the following group of very comprehensive questions, you should feel con dent that you have really mastered this section. You can refer back to the indicated pages to check your answers and/or review the subject matter. 1. Identify the bony structures composing the appendicular skeleton; be prepared to discuss and answer questions relevant to anatomy and pathology of the appendicular skeleton, bone structure and development, characteristics, and articular classi cations. 2. Describe the (a) method of positioning, (b) direction and point of entry of the CR, (c) principal structures visualized, and (d) pertinent traumatic or pathologic

conditions and any technical adjustments they may necessitate relative to the appendicular skeleton, to include routine and special views of the A. Hand and wrist (pp. 106–108). B. Forearm and elbow (p. 109, 110). C. Humerus and shoulder (p. 111). D. Clavicle and scapula (pp. 111–113). E. Foot and ankle (pp. 124–127). F. Lower leg and knee (p. 128, 130). G. Femur and hip (p. 130, 131). H. Pelvis and sacroiliac joints (p. 132, 133). I. Long bone measurement (p. 134). J. Arthrography (p. 134).

THEAXIALSKELETON Neural/Vertebral Arch Composed o

• •

Two pedicles Two laminae

Encloses

•

Vertebral foramen

Supports Seven Processes

• • • •

Two superior articular processes Two inferior articular processes Two transverse processes One spinous process

T e axial skeleton (Fig. 6–43A; shaded) consists o the acial and cranial bones o the skull, the ve sections o the vertebral column, and the sternum and ribs o the thorax.

Vertebral Column T e vertebral column (Fig. 6–43B) is composed o 33 bones divided into 7 cervical, 12 thoracic, 5 lumbar, 5 ( used) sacral, and 4 ( used) coccygeal regions, with each region having its own characteristic shape. T e vertebral bodies gradually increase in size through the lumbar region. T e vertebrae are joined by ligaments and cartilage; the rst 24 are separate and movable, while the last 9 are xed. Intervertebral disks between the vertebral bodies orm amphiarthrotic joints. T e cervical and lumbar regions orm lordotic (convex anteriorly) curves; the thoracic and sacral regions orm kyphotic (convex posteriorly) curves (Fig. 6–43B, lateral). An exaggerated thoracic curve is called kyphosis (hunchback); an exaggerated lumbar curve is lordosis (swayback). Lateral curvature o the vertebral column is called scoliosis. Approximately one in 20 children has some degree o de ormity o their vertebral column. Scoliosis is most o en idiopathic (i.e., has no known cause), but a amilial tendency is o en noted. Scoliosis has emale predominance and is not associated with any symptoms o back pain or atigue. Scoliosis surveys are per ormed or a number o reasons. T ey help determine degree o severity and skeletal maturity, too much or progression, and ensure adequacy o treatment.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

S kull

Ce rvica l ve rte bra (thora cic a nd lumba r ve rte bra , a ls o) S houlde r girdle

Clavicle

S te rnum Ribs Rib ca rtila ge

S ca pula

Bone s of the che s t

Hume rus

Bone s of the a rm Ra dius Ilium S a crum Coccyx

Ulna

Bone s of the wris t a nd ha nd

Bone s of the hip a nd pe lvis

Ca rpa ls Me ta ca rpa ls P ha la nge s Fe mur

Pa te lla

Bone s of the le g

Fibula Tibia

Ta rs a ls Me ta ta rs a ls A

Bone s of the a nkle a nd foot

P ha la nge s

Figure 6–43. (A) The axial skeleton (shaded). (Modi ed with permission from Rice J. Terminology with Human Anatomy, 3rd ed. East Norwalk, CT: Appleton &Lange, 1995.) (continued)

T e typical vertebra has a body and a neural/vertebral arch surrounding the vertebral oramen. T e neural arch is composed o two pedicles, two laminae that support our articular 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 (lack o union, or malunion, results in spina bi da). 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

139

140

PART II IMAGING PRO CEDURES

S upe rio r views

C1 C2 C3 C4 C5 C6 C7 T1 T2 T3 T4 T5 T6 T7

Late ral views

S pinous proce s s La mina

S upe rior a rticula r fa ce t

Tra nsve rs e fora me n Tra nsve rs e proce s s

Body S pinous proce s s

(a) Ce rvic al ve rte brae

S pinous proce s s

T8

S upe rior a rticula r fa ce t

La mina

T9 T10

Tra nsve rs e proce s s

Tra nsve rs e cos ta l fa ce t

T11

Infe rior a rticula r proce s s

S upe rior cos ta l fa ce t

Tra nsve rs e cos ta l fa ce t

Infe rior cos ta l fa ce t

T12

Body

L1

Infe rior a rticula r fa ce t

(b) Tho rac ic ve rte brae

S pinous proce s s

L2 L3 S pinous proce s s

L4

S upe rior a rticula r fa ce t

L5

S upe rior a rticula r proce s s

Tra nsve rs e proce s s Pe dicle

S a crum

Body

S pinous proce s s

Coccyx (c ) Lumbar ve rte brae

B

Ante rio r vie w

Le ft late ral vie w

Infe rior a rticula r fa ce t

Figure 6–43. (Continued) (B) AP and lateral views of the vertebral column; superior and lateral views of typical vertebra from each vertebral section. (From Saladin K. Anatomy and Physiology: The Unity o Form and Function. 7th ed. New York, NY: McGraw-Hill Education; 2014, Figure 8.25, p. 251.)

attachment and superior and in erior articular processes or the ormation o zygapophyseal joints (classi ed as diarthrotic). T e consecutive vertebral oramina orm the vertebral, or spinal, canal—through which the spinal cord is enclosed. T e vertebral column permits exion, extension, lateral, and rotary motions through its various articulations. T e bodies o consecutive vertebrae articulate with each other and are separated by intervertebral disks. T e outer portion o the intervertebral disks is the brous annulus brosus, which encloses a central portion, the nucleus pulposus. Rupture o the intervertebral disk, or herniated nucleus pulposus (HNP), can push into the spinal canal or adjacent spinal nerve roots (Fig. 6–49). T is condition can cause back pain and even loss o neurologic unction in the areas that the a ected spinal nerves are distributed. Articulation Summary: Vertebral

• • • • • • • • •

Occipitoatlantal Atlantoaxial Costovertebral Costotransverse Lumbosacral Sacroiliac Sacrococcygeal Intervertebral Zygapophyseal/interarticular

Cervical Spine. T ere are seven cervical vertebrae (Fig. 6–44). T e atlas (C1) is a ring-shaped bone having no body and no spinous process; it is composed o an anterior and posterior arch, two lateral masses, and two transverse processes. T e anterior arch has a tubercle at its midpoint and has a acet on its posterior sur ace or articulation with the anterior portion o the odontoid process/dens. T e posterior arch has a tubercle as well. T e lateral masses have superior articular processes that articulate with the skull at the atlanto-occipital joint, where exion and extension occurs. Its lateral masses articulate in eriorly with the axis (C2). T e axis (C2) has a superior projection, the dens, or odontoid process. T e axis articulates superiorly with the atlas at the atlantoaxial joint, a pivot joint where rotation o the head takes place, and in eriorly with C3

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

Atla s

Zyga pophys e a l joint

Axis Body

S pinous proce s s e s

Pe dicle Tra ns ve rs e proce s s Tra ns ve rs e fora me n La mina

A

Rig ht late ral view B

Atla s Infe rior a rticula r proce s s

Axis

R

S upe rior a rticula r proce s s

Ve rte bra l ca na l C

Po s te rio r view

D

Figure 6–44. (A) Right lateral view of the cervical spine. (B) Lateral projection of the cervical spine. (Photo Contributor: Conrad P. Ehrlich, MD.) (C) Posterior view of the cervical spine. (D) AP projection of the cervical spine. (Photo Contributor: Conrad P. Ehrlich, MD.)

at the zygapophyseal articulation. T e dens has a acet on its anterior sur ace or articulation with the posterior aspect o the anterior arch o C1. T e spinous process o C2 is particularly large and strong. T e typical cervical vertebra is small and has a transverse oramen in each transverse process or passage o the vertebral artery and vein. T e cervical laminae are thin and narrow; they meet at midline to orm a short spinous process. Cervical spinous processes are almost horizontal and usually bi d. T e spinous process o C7 (vertebra prominens) is not bi d, is larger and more horizontal, and is a use ul positioning landmark. Fractures and/or dislocations o the cervical spine are usually due to acute hyper exion or hyperextension as a result o indirect trauma. Whiplash injury is caused by a sudden, orced movement in one direction and then the opposite direction (as in rear-end automobile impacts). Whiplash symptoms requently include neck pain and sti ness, headache, and pain and numbness o the upper limbs.

141

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PART II IMAGING PRO CEDURES

Whiplash is o en evidenced radiographically by straightening or reversal o the normal lordotic curve. Lateral projections o the cervical spine are sometimes per ormed to evaluate whiplash injury—by demonstrating the degree o anterior and posterior motion. Osteoarthritis is characterized in the cervical and lumbar spine by chronic, progressive degeneration o cartilage and hypertrophy o bone along the articular margins, characterized radiographically by narrowed joint spaces, and osteophytes. Osteoarthritis is o en observable in the articulations o the ngers, toes, hips, and knees, as well. able 6–25 provides a summary o positions/projections o the cervical spine. TABLE6–25. Cervical Spine Cervical Spine

Position o Part

AP

• • •

AP Atlas and Axis (open mouth)

• • •

Central Ray Directed

Structures Included/Best Seen

Supine or erect MSP grid Adjust exion so mastoid tip and occlusal plane are aligned

•

15–20º cephalad to thyroid cartilage

•

AP of lower 5 cervical vertebrae and intervertebral disk spaces

Supine or erect MSP grid Mouth open, adjust exion so mastoid tips and upper occlusal plane are aligned IR ( CR)

•

center of opened mouth

•

AP proj of C1 and C2 (Fig. 6–45A) and their articulations Too much exion superimposes teeth on odontoid Too much extension superimposes base of skull on odontoid

•

•

Note: If the upper portion of the odontoid process is not seen, the AP (Fuchs) or PA (Judd) projection may be attempted i upper cervical x or degenerative disease is not suspected. The PA is similar to a Waters position; the AP similar to the reverse Waters. The odontoid is seen projected within the foramen magnum. Since extension o the neck is required, this position must not be attempted i upper cervical x or degenerative disease is suspected. Lateral

• •

• •

Erect w/ L side adjacent to IR Chin slightly elevated, shoulders depressed MSP IR Centered at level of C4

•

C4

• •

•

Lateral proj all 7 vertebrae (Fig. 6–45B) Shows intervertebral jt spaces, zygapophyseal jts, spinous processes, bodies Due to unavoidable OID, a 72” SID should be used

Note: Lateral exion and extension projections (Fig. 6–46) may be obtained in this position in cases of whiplash injury. Note: A recumbent cross-table/horizontal beam lateral must be performed as the rst radiograph for trauma or suspected subluxation patients. The patient’s neck must not be moved and any cervical collar in place must stay in place until images have been reviewed for fx, subluxation, etc. Oblique (LAO and RAO)

• •

•

PA erect, MSP 45º to IR Centered to C5 (1″ inferior to thyroid cartilage) Chin slightly raised

•

15–20º caudad to center of IR

• •

•

Oblique cervical Best view of intervertebral foramina closest to IR Similar image can be obtained w/ LPO, RPO, CR cephalad, showing the foramina arthest from the IR (see Fig. 6–45C)

Note: Oblique cervical spine may be performed in the recumbent position on patients whose trauma prohibits moving them. The CR is directed 45º medially for one oblique and 45º laterally for the other. • Erect or recumbent lat • Lateral T2 • Midaxillary line centered to cervicothoracic grid, MSP IR (Swimmer's • Arm adjacent to IR over head lateral) • Depress opposite shoulder farthest from grid

•

•

Lat proj of the lower cervical and upper thoracic vertebrae Particularly useful for broad-shouldered individuals

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143

A D B

F

D

E

C

G C E A A

F B

L A B

B C

D E

G

F

R

C

Figure 6–45. (A) Open-mouth projection of C1–C2. Locate and identify the bony structures shown particularly well in this projection. A, occlusal plane/maxillary incisors; B, odontoid process/dens; C, body, C2/axis; D, base of skull; E, transverse process, C1; F, body, C1; G, atlantoaxial articulation. (B) Lateral projection of the cervical spine. A, zygapophyseal articulation; B, spinous process C7/vertebra prominens; C, tubercle of anterior arch, C1; D, odontoid process/dens; E, intervertebral joint/disk space; F, vertebral body, C5. (C) An RPO cervical spine. Locate and identify the bony structures shown particularly well in each projection. A, posterior arch, C1; B, spinous process, C2; C, intervertebral foramen, C3; D, spinous process, C4; E, pedicle, C5; F, transverse process, C4; G, body, C4. (Photo Contributor: Conrad P. Ehrlich, MD.)

Figure 6–46. Lateral projections of the cervical spine in exion and extension—used to demonstrate degree of anterior and posterior motion. (Photo Contributor: Conrad P. Ehrlich, MD.)

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PART II IMAGING PRO CEDURES

S pinous proce s s Tube rcle of rib

Tra ns ve rs e proce s s

Cos totra ns ve rs e a rtic.

Fa ce t for rib a rticula tion

Ne ck of rib Fa ce t of rib Fa ce t

Cos tove rte bra l a rtic.

Body

He a d of rib

Figure 6–47. Thoracic vertebra and its articulation with the rib (superior view).

Thoracic Spine. T ere are 12 thoracic vertebrae, which are larger in size than cervical vertebrae and which increase in size as they progress in eriorly toward the lumbar region. T oracic spinous processes are airly long and sharply angled caudally ( 8 usually has the longest vertical spinous process). T e bodies and transverse processes have articular acets or the diarthrotic rib articulations (see Fig. 6–47). A common metabolic bone disorder requently noted in radiographic examinations o the thoracic spine is osteoporosis. Osteoporosis is characterized by bone demineralization and can result in compression ractures o the vertebrae. T e condition is most common in sedentary and postmenopausal women. able 6–26 provides a summary o positions/projections o the thoracic spine. Lumbar Spine. T e ve lumbar vertebrae are the largest o the vertebral column and increase in size toward the sacral region. T e spinous processes are short and horizontal and serve as attachment or strong muscles (see Fig. 6–49). T e causes o lumbar pain are numerous. rauma, TABLE6–26. The Thoracic Spine Thoracic Spine

Position o Part

AP

• •

Supine, MSP tabletop/grid Top of IR 1″ above shoulders

Central Ray Directed •

T7

Structures Included/Best Seen •

•

AP proj of the thoracic vertebrae and intervertebral spaces It is helpful to use the anode heel e ect and/ or compensating ltration to provide more uniform density (see Fig. 6–48A)

Note: To demonstrate zygapophyseal jts, 70º obliques are performed. Lateral

• 5–15º cephalad • Lat proj of thoracic vertebrae L lat recumbent • Midaxillary line centered to • Especially bodies, intervertebral spaces and ( long axis of spine) table foramina (see Fig. 6–48B) • Arms long axis of body • Top of IR 1″ above shoulders Note: This exposure can be made at the end of expiration. Or, a long exposure time (with low mA) can be used while the patient breathes quietly. This has the e ect of blurring vascular markings and superimposed ribs. •

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

A

145

Figure 6–48. (A) AP projection of the thoracic spine. Note density di erence between upper and lower spine; this can be improved by using the anode heel e ect to advantage (placing cathode over lower spine). (B) Lateral projection of thoracic spine. “Breathing technique” has helped blur pulmonary vascular markings and provided good visualization of nearly all the thoracic vertebrae. (Photo Contributor: Stamford Hospital, Department of Radiology.)

B

Inte rve rte bra l fora me n S upe rior a rticula r proce s s

S pinous proce s s

La mina

Infe rior a rticula r proce s s

Tra ns ve rs e proce s s

Pe dicle

Ve rte bra l ca na l fora men Body

L5 Lowe r 4 lumbar ve rte brae

S e c o nd lumbar ve rte bra (s upe rio r view)

S upe rior a rticula r proce s s

Body

S upe rior a rticula r proce s s

S pinous proce s s

Infe rior articula r proce s s

Pe dicle La mina

S e c o nd lumbar ve rte bra (rig ht late ral view)

He rnia tion of nucle us pulpos us

Infe rior a rticula r proce s s

S pinous proce s s

S e c o nd lumbar ve rte bra (po s te rio r view)

S pina l ne rve roots

Cra ck in a nulus fibros us

S pina l ne rve

Nucle us pulpos us

Anulus fibros us

Figure 6–49. Lateral view of the lower lumbar vertebrae. Superior, right lateral, and posterior views of L2. View of ruptured intervertebral disk, or herniated nucleus pulposus (HNP), can push into the spinal canal or adjacent spinal nerve roots. HNP can cause back pain and loss of neurologic function. (lowermost gure: From Saladin K. Anatomy and Physiology: The Unity o Form and Function. 7th ed. New York, NY: McGraw-Hill Education; 2014.)

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PART II IMAGING PRO CEDURES

racture, spasm o the paralumbar muscles, herniated intervertebral disk, and osteoarthritis are a ew causes o low back pain. Some o the disorders that can be detected radiographically include osteoarthritis, spondylolysis, spondylolisthesis, and ankylosing spondylitis. Myelography and especially MRI are used to evaluate herniated intervertebral disks. ransitional vertebrae occur at the junction between spinal sections. T e lumbar and sacral areas o the vertebral column are the sections most commonly associated with transitional vertebrae. Lumbarization is the assimilation o S1 into what appears to be L6. Sacralization, more common than lumbarization, is the assimilation o L5 to the sacrum. able 6–27 provides a summary o positions/projections o the lumbar spine. Sacrum. T ere are ve used sacral vertebrae (Fig. 6–53A); the used transverse processes orm the alae. T e anterior and posterior sacral

TABLE6–27. The Lumbar Spine Lumbar Spine

Position o Part

AP

• •

Supine, MSP tabletop Knees exed, feet at on table

Central Ray Directed •

to L3

Structures Included/Best Seen • • •

AP proj of lumbar vertebrae L1–L4 Intervertebral spaces, transverse processes Flexion o the knees reduces lumbar curve and OID (see Fig. 6–50)

Note: The AP projection of the lumbar spine is most comfortable for very thin patients and those with low-back pain. The PAprojection has the advantages of delivering lower gonadal dose and of placing the intervertebral jts more closely parallel with the divergent x-ray beam. AP (L5–S1)

• •

Oblique (RPO and LPO)

• •

Supine, MSP tabletop Legs extended

•

AP recumbent Oblique 45º w/ spine centered to grid

•

To MSP at 30–35 cephalad to MSP, ≈1½″ above pubic symph L3

•

AP of lumbosacral articulation not seen on AP lumbar

•

Obl proj of lumbar vertebrae Especially for zygapophyseal articulations (L1–L4) of side adjacent to IR Opposite obl is done to show opposite articulations (see Fig. 6–51).

•

•

Note: This proj demonstrates the characteristic “scotty dogs” (see Fig. 6–51); obl lumbar spine may also be performed PA and demonstrates the zygapophyseal articulations away from the IR. Note: L5–S1 zygapophyseal articulations shown in 35° oblique. Lateral

• •

L lat recumbent Midaxillary line centered to grid

•

5–8º caudad to L3

• •

•

Lat proj Especially for vertebral bodies, interspaces, intervertebral foramina, spinous processes I MSP adjusted tabletop, CR is vertical (Fig. 6–52A)

Note: Lateral lumbar spine in exion and extension is often used to demonstrate the presence or absence of motion in area(s) of spinal usion. Lateral (L5–S1)

• • •

L lat recumbent Center MCP to grid Adjust MSP tabletop

•

CR IR 1½” inf to crest and 2” post to ASIS

• •

Lat proj L5–S1 I MSP not adjusted tabletop, CR is (Fig. 6–52B)

5–8º caudad

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

R

Figure 6–50. AP projection of the lumbar spine. Flexion of the knees reduces lumbar curve and OID and relieves strain on lower back muscles; patients are most comfortable with sponge or pillow support placed under knees. (Photo Contributor: Stamford Hospital, Department of Radiology.)

A

E

B C D

A

F

B

Figure 6–51. Oblique lumbar spine (A), illustrating the lumbar zygapophyseal joints. Anatomy corresponds to “Scotty Dog”seen in (B). Structures seen in gure A are as follows: The Scott’sy “ear”(C) corresponds to the superior articular process, his “nose”to the transverse process (F), his “eye”is the pedicle (E), his “neck”the pars interarticularis (B), his “body”is the lamina (D), and his “front leg”is the in erior articular process (A). (Photo Contributor: Stamford Hospital, Department of Radiology.)

147

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PART II IMAGING PRO CEDURES

A

L

B C D E

Figure 6–52. (A) Lateral projection of the lumbar spine. If MSP is adjusted parallel to tabletop, CR angulation is unnecessary. A, body, L2; B, intervertebral foramen; C, pedicle; D, intervertebral disk space; E, spinous process, L4. (B) Lateral projection L5–S1. (Photo Contributor: Stamford Hospital, Department of Radiology.)

L

A

B

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 to orm the sacrococcygeal joint. ables 6–28 through 6–31 provide a summary o positions/projections o the sacrum, sacroiliac joints, coccyx, and scoliosis series. TABLE6–28. The Sacrum Sacrum

Position o Part

AP

• •

Lateral

• •

Central Ray Directed

AP supine MSP tabletop

•

L lat recumbent 3″ posterior to MCP centered to grid

•

15–25º cephalad to midline to point m/w b/w pubic symphysis and ASIS a point 3″ post to ASIS

Structures Included/Best Seen •

AP proj of sacrum CR parallels sacral curve providing less distorted visualization (see Fig. 6–53B)

•

Lateral proj of sacrum

•

TABLE6–29. The Sacroiliac Joints Sacro Iliac Jts

Position o Part

AP axial

•

Supine, MSP centered

•

30–35º cephalad, to the midline approxi-mately 2″ below level of ASIS

•

Sacrum, SI joints, and L5–S1 articulation

AP Oblique (LPO and RPO)

•

Supine Obliqued 25–30º af ected side up Sagittal plane passing 1″ medial to ASIS centered to grid

•

a point 1″ me-sacroiliac dial to ASIS

•

SI jt of the elevated side Opposite oblique is similarly obtained; SI jt is placed IR (see Fig. 6–38A and B)

Prone and obliqued 25–30º af ected side down Sagittal plane passing 1″ medial to ASIS centered to grid

•

a point 1″ sacroiliac medial to ASIS

•

• •

PA Oblique (LAO and RAO)

•

•

Central Ray Directed

Structures Included/Best Seen

•

•

SI jt of the “down” side Opposite oblique is similarly obtained; SI jt is placed IR–35º cephalad.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

S a cra l tube ros ity Me dia n s a cra l cre s t

S upe rior a rticula r proce s s

Ala

P romontory

La te ra l s a cra l cre s t Me dia n s a cra l cre s t

Auricula r s urfa ce S pinous proce s s

Dors a l s a cra l fora men

Coccyx Apex of s a crum

Apex of coccyx Rig ht late ral view

Po s te rio r vie w

A

B

C

Figure 6–53. (A) Sacrum and coccyx. (B) AP projection of the sacrum. Cephalad angulation “opens”the sacral foramina. (C) AP projection of the coccyx. Caudal angulation “opens”the coccygeal curve. (Photo Contributor: Stamford Hospital, Department of Radiology.)

Coccyx (see Table 6–30). T ere are our or ve used coccygeal vertebrae (see Fig. 6–53A). Fracture o the coccyx usually results rom a all onto it, landing in a seated position. Fracture displacement is airly common and occasionally requires removal o the ractured ragment to relieve the pain ul symptoms. Scoliosis Series. See able 6–31 or positioning or a scoliosis series.

149

150

PART II IMAGING PRO CEDURES

TABLE6–30. The Coccyx Coccyx

Position o Part

AP

• •

Lateral

• •

Central Ray Directed

AP supine MSP tabletop

•

L lateral recumbent 5″ post to MCP centered to grid

•

Structures Included/Best Seen

10–20º caudad to midline to point 2″ above pubic symphysis

•

a point 5″ post to MCP at level of mid-coccyx

•

•

AP proj of coccyx CR parallels coccygeal curve providing less distorted visualization (see Fig. 6–53C) Lat proj of coccyx and its articulation with the sacrum

TABLE6–31. Scoliosis Series Scoliosis Series

Position o Part

PA bending

• • •

PA or AP Ferguson method

• • •

Central Ray Directed

Structures Included/Best Seen

14″ × 17″ or 14″ × 36″ IR Vertebrae to include 1″ of iliac crest/L5–S1 Four exposures made: • PA recumbent • PA erect • PA bending L • PA bending R

•

center of IR

•

Radiation dose is reduced when gonadal, breast, and thyroid shields are used and when examination is performed PA rather than AP (Fig. 6–54)

14″ × 17″ or 14″ × 36″ IR Vertebrae to include 1″ of iliac crest/L5–S1 Three exposures made with no rotation: • PA(or AP) • PA w/ (3″–4″) block under one foot • PA w/ (3″–4″) block under opposite foot

•

center of IR

•

Images used to distinguish primary curve from compensatory curve Protective shielding must be utilized

•

Articulation Summary: Thorax

• • • • •

Sternoclavicular Sternochondral Costochondral Costovertebral Costotransverse

Figure 6–54. AP scoliosis series with protective shielding in place. (Photo Contributor: Nuclear Associates.)

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151

TABLE6–32. The Sternum Sternum

Position o Part

PA Oblique (RAO)

• • •

Central Ray Directed

15–20º RAO Greater obliquity for thin patients Sternum centered to midline of table/grid

•

midsternum

Structures Included/Best Seen • •

Obl–frontal RAO proj Projects sternum into heart shadow for uni orm density.

Note: Along exposure can be used during quiet breathing to blur pulmonary vascular markings, or exposure can be made on expiration (Fig. 6–55). Lateral

• • • •

Erect L lateral Shoulders rolled back MSP vertical IR top 1.5″ above manubrial notch

•

midsternum

•

•

Lat proj of sternum free of superimposition of ribs Exposure made on deep inspiration to move sternum away from ribs

Thorax Sternum and Sternoclavicular Joints. (See ables 6–32 and 6–33.) T e bones o the thorax (sternum, ribs, thoracic vertebrae; Fig. 6–56) unction to protect the vital organs within heart, lungs, and major blood vessels. Minor trauma to the thorax can result in uncomplicated lacerations, contusions, or simple rib racture. However, more signi cant trauma, like those o en associated with MVAs, can have more serious consequences as a result o numerous rib ractures causing injury to the mediastinum, pleural cavity, and/or heart and great blood vessels. T e sternum orms the anterior central portion o the thorax and is composed o three major divisions: the manubrium, body, and xiphoid process. T e articulation between the manubrium and body is the sternal angle (angle o Louis), which coincides with the location o the second rib. Sternal ractures are uncommon; when they do occur, racture displacement is rare, but the possibility o traumatic injury to the heart must still be considered. Ribs. (See able 6–34) T e rib cage (see Fig. 6–56) consists o 12 pairs o ribs. Ribs 1 to 7 articulate with thoracic vertebrae and the sternum and are called vertebrosternal or “true” ribs. T e rst pair o ribs lies under the clavicles and is not palpable; the remaining 11 pairs o ribs are usually palpable. Ribs 8 to 10 articulate with thoracic vertebrae and the superjacent costal cartilage to orm the anterior costal margin and are called vertebrochondral or alse ribs. T e last two pairs o alse ribs articulate only with thoracic vertebrae and are re erred to as oating ribs. T e lower edge o the rib cage orms the in erior costal margin. T e spaces between the ribs are called intercostal spaces and are occupied by two sets o intercostal muscles.

Radiographically Signi cant Skeletal Disorders and Conditions o the Axial Skeleton Achondroplasia Ankylosing spondylitis Cervical rib Degenerative disk disease Flail chest Herniated disk Hydrocephalus Kyphosis Lordosis Osteophyte Osteoporosis Pectus excavatum Scoliosis Spina bi da Spondylolisthesis Spondylolysis Transitional vertebra Whiplash

TABLE6–33. The Sternoclavicular Joints Sterno-clavicular Joints

Position o Part

PA

• •

PA Oblique (LAO and RAO)

• •

Central Ray Directed

Structures Included/Best Seen

Prone, MSP centered to grid IR centered at T3 (suprasternal notch)

•

T3

•

Bilateral PA proj of sternoclavicular jts visualized through superimposed vertebrae and ribs

Prone, MSP centered to grid Rotate ≈15º af ected side down

•

a ected jt

•

Oblique projection of the sternoclavicular jt closest to IR Similar results obtained w/ MSP and CR 15º toward midline from the a ected side

•

152

PART II IMAGING PRO CEDURES

A

B

C

fx

D

E

Figure 6–55. (A) RAO sternum. A, medial extremity of clavicle; B, manubrium; C, sternal angle; D, body/ gladiolus; fx site of displaced fracture. “Breathing technique”helps blur superimposed structures and permits improved visualization of bony sternum. (B) RAO of same sternum, exposed on suspended respiration. (Photo Contributor: David Sack, BS, RT (R), CRA, FAHRA.)

A

B

S te rnoclavicula r joint S te rnum:

Acromioclavicula r joint T1 1

Pe ctora l girdle : Clavicle S ca pula

S upra s te rna l notch Clavicula r notch Ma nubrium

2

Angle

3 Body

4

True ribs (1–7) 5

Xiphoid proce s s 6 7

11

8 Fa ls e ribs (8–12)

Floa ting ribs (11–12)

9 10

12

T12

Cos ta l ca rtila ge s

L1 Cos ta l ma rgin

Figure 6–56. The thoracic cage and pectoral girdle, anterior aspect. (From Saladin KS. Anatomy and Physiology: The Unity o Form and Function. 7th ed. McGraw-Hill.)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

153

TABLE6–34. The Ribs Ribs

Position o Part

AP

• • •

PA Oblique (LAO, RAO) AP Oblique (LPO, RPO)

• •

• •

Central Ray Directed

Supine or AP erect MSP midline of table Top of IR 1″ above shoulder

•

Prone or erect PA Rotate 45º, una ected side down

•

Supine or erect AP Rotate to 45º a ected side toward IR

•

center of IR, about level of T7

Structures Included/Best Seen • • •

center of IR, about level of T7 (at T10-T12 for below diaphragm)

•

center of IR, about level of T7 (at T10–T12 for below diaphragm)

•

• •

•

AP proj Upper posterior ribs best delineated Do PA for better detail of anterior ribs Obl shows axillary portions of ribs RAO shows left ribs LAO shows right ribs LPO shows le t posterior ribs and their axillary portions RPO shows right posterior ribs and their axillary portions

Note: Above-diaphragm ribs are exposed on deep inspiration or during quiet breathing (long exposure). Below-diaphragm ribs are best demonstrated when exposed on orced expiration.

Rib ractures are a common injury in thoracic trauma because o their relative thinness and exposed position. T eir racture may be complicated by pneumothorax, hemothorax, liver laceration (right lower ribs), or spleen laceration (le lower ribs).

Head and Neck Skull. T e skull has two major parts: the cranium, which is composed o eight bones and houses the brain, and the 14 irregularly shaped acial bones (Figs. 6–57 and 6–58). T e eight cranial bones are the paired parietal and temporal bones and the unpaired rontal, occipital, ethmoid, and sphenoid bones. T e 14 acial bones include the paired nasal, lacrimal, palatine, in erior nasal conchae, maxillae, and zygomatic bones and the unpaired vomer and mandible. T e average-shaped skull is termed mesocephalic (petrous pyramids and MSP orm ≈47°), the broad skull is termed brachycephalic (petrous pyramids and MSP orm ≈54°), and the elongated skull is termed dolichocephalic (petrous pyramids and MSP orm ≈40°). T ese deviations are readily observable in axial C and MR images. T e inner and outer compact tables o the skull are separated by cancellous tissue called diploë. 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 (see Figs. 6–57 and 6–58). T e articular sur aces o these bones have serrated-like edges with small projecting bones called wormian bones that t together to orm the articular sutures. T e sagittal and coronal sutures meet at the bregma, which corresponds to the etal anterior ontanel. T e 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 (see Fig. 6–57), the location o the anterolateral ontanel. T e highest point o the skull is called the vertex.

154

PART II IMAGING PRO CEDURES

Fronta l bone

Gla be lla

Na s a l bone

Na s ion

La crima l bone Pa rie ta l bone

S upra orbita l fora me n

Ethmoid bone S phe noid bone Optic fora me n

Zygoma tic proce s s

Orbita l cavity

Infe rior orbita l fis s ure S upe rior orbita l fis s ure

Te mpora l bone

Infra orbita l fora me n Zygoma tic bone

Zygoma tic a rch

Ethmoid bone Ma s toid proce s s

Na s a l concha e /turbina te s Ra mus of ma ndible

Na s a l cavity Vome r

Ma xilla Angle of ma ndible

Me nta l fora me n A

S ymphys is me nti

Ma ndible

Pa rie ta l Squamosal bone suture Te mpora l bone

Bre gma Coronal suture Fronta l bone P te rion

As te rion

Gre a te r wing of s phe noid

La mbda

Gla be lla

Lambdoidal suture

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

B

Angle of ma ndible

Ma ndible

Figure 6–57. (A) Anterior view of the skull, labeled. (B) Lateral view of the skull, labeled.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

Sagittal suture

155

La mbda

Pa rie ta l bone Lambdoidal suture

A Occipita l bone

C

As te rion Te mpora l bone

Ma s toid proce s s

B

D E

Occipita l condyle

A

Inion, or exte rna l occipita l protube ra nce B

Figure 6–58. (A) Posterior view of the skull, labeled. (B) AP axial skull (Towne) demonstrates the occipital bone. A, petrous ridge; B, petrous portion of temporal bone; C, foramen magnum; D, dorsum sella and posterior clinoid processes; E, mandibular condyle. (Photo Contributor: Stamford Hospital, Department of Radiology.)

Cranial Bones Frontal Bone

• T e rontal bone corresponds to the orehead region (Fig. 6–57) • Orbital plates (2): horizontal part o rontal bone; orms much o superior aspect o bony orbit • Frontal eminences (2): on anterior sur ace o rontal bone, lateral to MSP • Glabella: smooth prominence between eyebrows • Frontal sinuses (2): directly behind glabella, between the tables o the skull • Superciliary arches/ridges (2): ridge o bone under eyebrow region • Supraorbital margins (2): upper border/rim o bony orbit • Supraorbital notches/ oramina (2): midportion o supraorbital margin; passage or artery and nerve to orehead • Frontonasal suture: where rontal bone articulates with nasal bones (corresponds exteriorly with nasion) Parietal Bones

• Paired; orm the vertex and part o lateral portions o the cranium • Meet at midline to orm sagittal suture; other borders help orm coronal, squammosal, and lambdoidal sutures (Fig. 6–58) • Parietal eminences: rounded prominence on the lateral sur ace o each parietal bone Ethmoid Bone

• Located between orbits; helps orm parts o nasal and orbital walls (Figs. 6–57 and 6–59)

Cranial Bones (8) (1) Frontal (2) Parietal (2) Temporal (1) Occipital (1) Ethmoid (1) Sphenoid

156

PART II IMAGING PRO CEDURES

• Cribri orm plate: porous, passage or ol actory nerves; horizontal portion between orbital plates o rontal bone • Crista galli: extends superiorly rom midportion o cribri orm plate • Perpendicular plate: extends downward rom crista galli to orm major portion o nasal septum • Superior and middle nasal turbinates/conchae: cartilaginous; within nasal cavity, attached to perpendicular plate • Ethmoidal labyrinths/lateral masses: help orm medial wall o orbit; ethmoidal sinuses within Sphenoid Bone

Types o Fractures Linear fx A skull fx, straight and sharply de ned Depressed fx A comminuted skull fx, with one or more portions pushed inward Hangman fx Fx of C2 with anterior subluxation of C2 on C3; result of forceful hyperex-tension Compression fx Especially of spongy (cancellous) bone; diminished thickness or width as a result of compression-type force (e.g., vertebral body) Blowout fx Fx of orbital oor as a result of a direct blow

• Wedge- or bat-shaped bone located between rontal and occipital bones (Figs. 6–59 to 6–61) • Anchor or eight cranial bones • Forms small part o lateral cranial wall and part o skull base • Consists o body, two lesser wings, two greater wings, two pterygoid plates/processes, and hamuli • Body: central portion; midline o skull base; anterior part joins ethmoid bone; contains the two sphenoid sinuses • Lesser (minor) wings: anterior portion, articulates with orbital plates; contain optic canals or passage o optic nerves and ophthalmic arteries • Anterior clinoid processes: ormed by medial aspect o lesser wings • uberculum sellae: ridge o bone between anterior clinoid processes; anterior boundary o sella turcica • Optic (chiasmic) groove: horizontal depression crossing body o bone in ront o sella turcica, where optic nerves cross • Optic oramen and canal: passage or optic nerve and ophthalmic artery at the orbit’s apex • Sella turcica: deep depression in sphenoid bone; houses pituitary gland • Dorsum sellae: posterior boundary/wall o sella turcica • Posterior clinoid processes: extend laterally rom dorsum sellae • Clivus: basilar portion; slopes down and posteriorly rom dorsum sellae; articulates with basilar portion o occipital bone • Superior orbital ssures: large spaces between greater and lesser wings; or passage o our cranial nerves • Greater (major) wings: larger, posterior portion o sphenoid bone; contains the oramina rotundum, ovale, and spinosum or transmission o cranial nerves • Pterygoid processes: extend in eriorly rom junction o body with great wing; each has a medial and lateral plate that articulates with posterior part o adjacent maxillae • In erior orbital ssures: large openings, lie between the greater wings and the maxilla Occipital Bone • Forms part o posterior wall and in erior part o the cranium (Figs. 6–58A and B and 6–59)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

Fo ramina

Olfa ctory ne rve s

Cribriform pla te of e thmoid Optic fora me n

Ante rior cra nia l fos s a

S upe rior orbita l fis s ure

S phe noid ridge

Middle cra nia l fos s a Pe trous pyra mid

Optic ne rve Ophtha lmic a rte ry Me ninge s Oculomotor, trochle a r, a nd a bduce ns ne rve s a nd ophtha lmic divis ion of trige mina l ne rve ; s upe rior ophtha lmic ve in

Fora me n rotundum

Ma xilla ry divis ion of trige mina l ne rve

Fora me n ova le

Ma ndibula r divis ion of trige mina l ne rve

Fora me n la ce rum

Inte rna l ca rotid a rte ry S ympa the tic plexus

Fora me n s pinos um

Middle me ninge a l a rte ry a nd ve in

Inte rna l a cous tic me a tus Jugula r fora me n

Fa cia l a nd a uditory ne rve s Inte rna l a uditory a rte ry

Hypoglos s a l ca na l Pos te rior cra nia l fos s a

S truc ture s

Fora me n ma gnum

Glos s opha rynge a l, va gus, a nd s pina l a cce s s ory ne rve s Tra ns ve rs e s inus Hypoglos s a l ne rve Me dulla a nd me ninge s S pina l a cce s s ory ne rve Ve rte bra l a rte rie s Ante rior a nd pos te rior s pina l a rte rie s

Figure 6–59. Base of the skull showing the fossae and principal foramina (superior view).

• Upper portion o each side articulates with parietal bones to orm lambdoidal suture • Basilar portion: articulates anteriorly with basilar portion (clivus) o sphenoid bone • Lateral portions (2): bilateral to oramen magnum; occipital condyles, hypoglossal canals, and jugular oramina located here • Foramen magnum: large opening; transmits in erior portion o brain (medulla oblongata), which is continuous with spinal cord • Squammosal portion: posterior, superior portion; presents the external occipital protuberance (inion, occiput) emporal Bones

• Irregularly shaped bones orming lateral aspects o the cranium • Located between greater wings o sphenoid bone and occipital bone (Figs. 6–57 and 6–60A and B) • Dense, petrous portions orm ridges and contain the organs o hearing • Contain internal auditory meati and carotid canals • Zygomatic processes: extend rom at, squammous portion; articulate with zygomatic ( acial) bones

Facial Bones (14) (2) Nasal (2) Lacrimal (smallest) (2) Palatine (2) Inferior nasal conchae (2) Zygomatic/malar (2) Maxillae (1) Vomer (1) Mandible (largest; only movable)

157

158

PART II IMAGING PRO CEDURES

Incis ive fora me n

Pos te rior na s a l a pe rture

Ma xilla

Vome r Me dia l pte rygoid pla te Te mpora l bone

Zygoma tic bone Fronta l bone

Fora me n la ce rum

S phe noid bone Zygoma tic a rch

Fora me n ova le

La te ra l pte rygoid pla te S tyloid proce s s

Exte rna l a cous tic me a tus

Jugula r fora me n Ma s toid proce s s

Ma ndibula r fos s a

Pa rie ta l bone Exte rna l occipita l cre s t

Ca rotid ca na l

Occipita l bone

Occipita l condyle

As te rion Pos te rior condyla r ca na l

Inion, or exte rna l occipita l protube ra nce

Fora me n ma gnum

A

A E F B C

Figure 6–60. (A) Basal view of the skull (external aspect, inferior view). (B) SMV skull demonstrates the base of the skull. A, mandible; B, anterior arch C1; C, odontoid process/dens; D, foramen magnum; E, sphenoid sinuses; F, auditory canal. (Photo Contributor: Stamford Hospital, Department of Radiology.)

D

B

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

159

• Mandibular ossae: articulate with mandibular condyles to orm temporomandibular joints ( MJs) • emporal styloid processes: sharp, slender processes extending anteriorly and in eriorly to mastoid processes • External auditory meatus (EAM): external openings o the ear canal • Mastoid processes: in erior to EAM; contain numerous air cells; communicate with tympanic cavity (middle ear) at mastoid antrum Facial Bones Nasal Bones

• • • • •

Small, rectangular (Fig. 6–57) Form bridge o nose Movable part o nose is composed o cartilage Articulate with each other at midline to orm nasal suture Frontonasal suture: ormed by articulation with rontal bone; corresponds to nasion externally

Lacrimal Bones

• Smallest o acial bones • Form part o medial orbital wall (Fig. 6–57) • Lacrimal groove: accommodates lacrimal (tear) duct Zygomatic (Malar) Bones

• In erior and lateral to outer canthus o eye; cheek bones • Have our processes: rontosphenoidal, orbital, temporal, and maxillary (Fig. 6–57) Maxillae

• Second largest o acial bones (Figs. 6–57 and 6–60) • Articulate with each other to orm most o upper jaw (hard palate) • Palatine processes: plates o bone that articulate at midline to orm two-thirds o the hard palate

1 8° 7°

2 3

4

Figure 6–61. Four fundamental baselines used in skull radiography: (1) the glabellomeatal (GML), (2) the orbitomeatal (OML, also known as canthomeatal or radiographic baseline), (3) the infraorbitomeatal (IOML), and (4) the acanthiomeatal line. There is approximately a 7° di erence between the OML and IOML and an 8° between the OML and GML.

160

PART II IMAGING PRO CEDURES

• Form most o roo o mouth (hard palate) and oor o nasal cavity • Contain the maxillary sinuses (maxillary antra; antra o high-more) just superior to bicuspid teeth; the thin oor o the maxillary sinus is ormed by the alveolar process • Alveolar ridge/process: contains sockets or teeth; spongy ridge o bone • Anterior nasal spine: corresponds to acanthion externally • In raorbital oramen: located below orbit, lateral to nasal cavity Palatine Bones

• Small bones; orm posterior one-third o hard palate (Fig. 6–60) • L-shaped; have vertical and horizontal processes • Horizontal parts: articulate with palatine processes o maxillae to complete the hard palate • Vertical parts: project superiorly rom horizontal part to articulate with the sphenoid bones Inferior Conchae (Nasal urbinates)

• Completely osseous (Fig. 6–57) • Placed in eriorly on each lateral wall o nasal cavity Vomer

• In erior to perpendicular plate o ethmoid bone • Forms posterior bony septum (Fig. 6–57A) • Choanae: posterior opening into nasopharynx; separated by posterior portion o vomer Mandible • U-shaped bone; largest acial bone (Fig. 6–57) • Only movable acial bone • Mandibular symphysis: where two halves use a er birth • Mental tubercles: prominences at in erolateral margin o symphysis • Mental protuberance: protuberance at lower portion o symphysis • Alveolar process/ridge: spongy ridge o bone with sockets or teeth • Body: horizontal position • Ramus: posterior vertical portion • Angle: junction o vertical and horizontal parts: corresponds to external landmark: gonion • MJ: articulation o head o condyle with mandibular ossa o temporal bone; only movable articulation in skull • Coronoid process: extends anterior and superior rom ramus and has no articulation; serves as muscle attachment • Mandibular notch: deep notch between condyloid and coronoid processes • Mental oramen: small opening on outer sur ace o body, approximately below second premolar; passage or mandibular nerve • Mandibular oramen: opening on inner side o ramus or mandibular nerve ables 6–35 through 6–41 provide a summary o positions/projections o the cranium and all acial bones.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

161

TABLE6–35. The Cranium Cranium

Position o Part •

•

nasion

Structures Included/Best Seen

PA proj of skull • • Petrous pyramids should ll the orbits • Demonstrates frontal bone, lateral cranial walls, frontal sinuses, crista galli (see Fig. 6–62) Note: General survey cranium can be obtained with CR 15º caudad to nasion (ridges ll lower 1/3 orbits). Similar projections of the same structures may be obtained AP with OML vertical if the CR is directed in the opposite direction. Anterior structures will be somewhat magni ed and eye/lens dose will be greater. • PA, MSP centered to grid • 15º caudad to nasion • PA axial of cranium PA axial • OML • Petrous portions in lower third of orbits (Caldwell) grid • IR centered to nasion • Frontal and ethmoid sinuses seen (see Fig. 6–70) • 25º to 30° angle will better demonstrate inferior orbital ssures • Supine, MSP • 30º caudad to a point • AP axial of skull AP axial midtable • OML vertical • Especially for occipital bone (Towne) ≈1.5″ above glabella • Top of IR 1.5″ below vertex • Symmetrical proj of petrous pyramids (or 37º to IOML) • Projects dorsum sella and post clinoid processes w/ in the foramen magnum (Fig. 6–63A) Notes: • Excessive tube or neck exion will project posterior arch of C1 into foramen magnum. • Similar results can be obtained in the PA position (PA axial; Haas method) with the CR 25º cephalad to the OML; the CR enters 1½″ below the inion and exits 1½″ above the nasion; it is particularly useful for hypersthenic or kyphotic patients, although some magni cation of the occipital bone must be expected. • An AP axial of the zygomatic arches can be obtained by directing the CR to the glabella and decreasing the technical factors. • Skull MSP grid • • Lat proj of skull Lateral a point 2″ superior to • Interpupillary line vertical • Demonstrates superimposed cranial and facial EAM • IOML transverse axis structures • Anterior and posterior clinoid processes should of IR be superimposed • Supraorbital margins should be superimposed (see Fig. 6–63B) • Supine or seated AP • • Full basal proj of skull, useful for many foramina Full basal IOML and IR, enters • Neck hyperextended to proj; MSP at level of sella (spinosum, ovale, carotid canals • Sphenoid and maxillary sinuses seen submentoplace IOML IR • CR and MSP • Dens seen through foramen magnum vertex IR • Symmetrical proj of petrous pyramids w/ mandi(SMV) bular condyles projected anterior to petrosae • Mandibular symphysis superimposed on frontal bone (see Figs. 6–60B and 6–64) Note: A decrease of 10 kV will demonstrate a bilateral axial projection of the zygomatic arches (see Figs. 6–64B and 6–65). • Supine, MSP • • AP proj of skull AP (trauma) mid-table nasion • OML • Petrous pyramids should ll the orbits IR • AP, MSP centered to grid • 15º cephalad to nasion • AP axial of cranium AP axial • OML • Petrous portions in lower third of orbits (trauma) grid • IR centered to nasion • Facial structures somewhat magni ed • Supine, dorsal decubitus • • Lat proj of skull in dorsal decubitus position Lat (trauma) IR, 2″ lat superior to • Head supported on sponge • Can demonstrate sphenoid sinus e usion as the EAM. • Grid IR vertical and adjacent only sign of basal skull fx to side of interest • MSP CR and to IR • Interpupillary line IR. PA

Prone, MSP midtable OML IR (see Fig. 6–62)

Central Ray Directed

•

162

PART II IMAGING PRO CEDURES

B

A

C D

E

R

Figure 6–62. PA skull radiograph; the correct amount of exion places the petrous pyramids within the orbits. A, ethmoid sinuses; B, petrous portion of temporal bone; C, mastoid air cells/process; D, vomer; E, mandibular angle. (Photo Contributor: Stamford Hospital, Department of Radiology.)

A B D

C F

E

G

R A

L B

Figure 6–63. (A) AP axial (Towne method) projection of the skull; demonstrates the dorsum sella and posterior clinoid processes within the foramen magnum; useful for demonstration of the occipital bone. (B) Lateral projection of the skull. A, supraorbital margins; B, anterior clinoid processes; C, dorsum sella; D, sphenoid sinus; E, mastoid air cells; F, external auditory meatus; G, maxillary sinus. (Photo Contributor: Stamford Hospital, Department of Radiology.)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

R A

R B

Figure 6–64. (A) Submentovertical (SMV) skull. The success of this projection depends on positioning the CR the IOML and IR. (B) SMVprojection of the skull, collimated and exposure factors adjusted to demonstrate zygomatic arches. Note fracture of right zygomatic arch. (Photo Contributor: Stamford Hospital, Department of Radiology.)

Orbits. T e orbital cavities are ormed by seven bones ( rontal, sphenoid, ethmoid, maxilla, palatine, zygoma/malar, and lacrimal). T e orbital walls are ragile and the orbital oor is subject to traumatic blowout ractures—the second most common acial racture (nasal x is #1). Orbital ractures can be accompanied by injury to adjacent structures—bone,

Figure 6–65. SMV projection of bilateral zygomatic arches. (Photo Contributor: Stamford Hospital, Department of Radiology.)

163

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PART II IMAGING PRO CEDURES

muscle, other so tissue. Leakage o air rom the adjacent maxillary sinuses can cause orbital edema. Orbital oor ractures can be demonstrated using the parietoacanthial (Waters) projection; C is o en indicated or urther evaluation (see able 6–36).

TABLE6–36. The Orbits Orbits

Position o Part

Parietoacanthial (Waters)

• •

Central Ray Directed

PA w/ MSP and centered to grid Chin extended so OML is 37º to IR

•

to parietal region, exiting at acanthion

Structures Included/Best Seen Axial proj of facial bones, especially orbits, zygomas, and maxillae Best single proj for acial bones

•

•

Note: X-ray beam may be collimated to orbital region, with CR passing through MSP, and exiting midorbits. PA axial (Caldwell)

• • •

PA, skull MSP centered to grid OML grid IR centered to nasion

•

15º caudad to nasion

PA axial of orbits, nasal septum, maxillae, and zygomas Petrous pyramids are seen in the lower one-third o the orbits

•

•

Note: X-ray beam may be collimated to orbital region, with CR passing through MSP, and exiting midorbits. Lateral

• • •

Skull MSP grid Interpupillary line vertical IOML transverse axis of IR

•

a point 2″ superior to EAM

Lat proj of skull Demonstrates superimposed cranial and facial structures Anterior and posterior clinoid processes should be superimposed Supraorbital margins should be superimposed

• •

•

•

Note: X-ray beam may be collimated to orbital region, with CR passing parallel to interpupillary line.

Facial Bones, Zygomatic Arches, and Nasal Bones (Tables 6–37 through 6–39) TABLE6–37. The Facial Bones Facial Bones

Position o Part

Parietoacanthial (Waters)

• •

Central Ray Directed

PA, MSP centered to grid chin extended so OML is 37º to IR

•

to parietal region, exiting at acanthion

Structures Included/Best Seen

•

Axial proj of facial bones, especially orbits, zygomas, and maxillae Best single proj for acial bones

•

Lat proj of superimposed facial bones

•

PA axial of facial bones Petrous portions in lower third of orbits

•

Note: Patient should be upright to demonstrate air/ uid levels. Lateral

Skull MSP table/grid Interpupillary line IOML to transverse axis of IR

•

•

•

PA, MSP centered to grid OML grid IR centered to nasion

AP axial trauma (Reverse Waters)

•

Supine, MSP

•

CR cephalad, mentomeatal line (MML) and entering acanthion

•

Axial, but magni ed, proj of facial bones

Lateral trauma

•

Supine, dorsal decubitus Use “crosstable,” horizontal beam

•

CR enters 2″ superior to EAM; grid cassette placed adjacent to lateral aspect of patient skull

•

Lat proj of facial bones in dorsal decubitus position Can demonstrate sphenoid sinus e usion as the only sign of basal skull fx

• • •

PA axial (Caldwell)

• •

•

midtable

zygoma

15º

caudad to nasion

•

•

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

165

TABLE6–38. The Zygomatic Arches Zygomatic Arches

Position o Part

Full basal position/ submentovertex proj (SMV)

• •

•

Central Ray Directed

Supine or seated AP Neck hyperextended to place IOML IR CR and MSP IR

•

IOML and IR, enters MSP at level of sella

Structures Included/Best Seen •

• • •

•

Full basal proj of skull, useful for many foramina (spinosum, ovale, carotid canals) Sphenoid and maxillary sinuses seen Dens seen through foramen magnum Symmetrical proj of petrous pyramids w/ mandibular condyles projected anterior to petrosae Mandibular symphysis superimposed on frontal bone (see Figs. 6–60B and 6–64)

Note: In this projection, the skull may be rotated 15º toward the af ected side to better “open up” the zygomatic arches in individuals having at cheekbones or a depressed fx. AP axial (Towne)

• •

Parietoacanthial (Waters)

•

•

Supine, MSP OML vertical

midtable

PA w/ MSP and centered to grid Chin extended so OML is 37º to IR

•

30º caudad to glabella (or 37º to IOML)

•

AP axial of zygomatic arches free of superimposition

•

to parietal region, exiting at acanthion

•

Axial proj of facial bones, especially orbits, zygomas, and maxillae Best single proj for acial bones

•

Note: Patient could be examined in the upright position to demonstrate air/ uid levels.

TABLE6–39. The Nasal Bones Nasal Bones

Position o Part

Lateral

• • •

Central Ray Directed

MSP of skull table Interpupillary line IOML to transverse axis of IR

•

a point 3/4″ dist to nasion; include nasofrontal suture through anterior nasal spine of maxilla

Structures Included/Best Seen •

•

Lat proj of superimposed nasal bones Their associated soft tissue (see Fig. 6–66)

Note: The parietoacanthial (modi ed Waters) and PAaxial (Caldwell) from acial bone series are most often included in the nasal bone series.

Figure 6–66. Lateral nasal bones demonstrating fracture. (Photo Contributor: Stamford Hospital, Department of Radiology.)

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PART II IMAGING PRO CEDURES

Mandible and Temporomandibular Joints (TMJs) (See Tables 6–40 and 6–41) TABLE6–40. The Mandible Mandible

Position o Part

PA

• •

PA axial

• •

Axiolateral oblique

AP axial (Towne)

• •

•

•

Full basal proj/ submentovertex (SMV)

• •

•

A

Central Ray Directed

PA, MSP of skull IR centered to tip of nose

•

PA, MSP of skull IR centered to glabella

•

MSP of skull IR centered 1/2″ anterior and 1″ inferior to the EAM

•

Supine, MSP of skull midtable OML vertical Supine or seated AP Neck hyperextended to place IOML IR CR and MSP IR

the lips

Structures Included/Best Seen •

PA proj of mandible, especially body and rami (Fig. 6–67A)

20–25º cephalad to center of IR

•

PA axial mandible, especially for rami and condyles

25º cephalad, enters at mandibular angle of una ected side

•

Axiolateral mandible, especially for body and ramus Rotate MSP 15º forward to better demonstrate body (see Fig. 6–67B)

•

30º caudad through midramus (or 37º to IOML)

•

AP axial of mandibular rami free of superimposition

•

IOML and IR, enters MSP at level of sella

•

Full basal proj of skull Useful for odontoid process through foramen magnum Symmetrical proj of petrous pyramids w/ mandibular condyles projected anterior to petrosae and symphysis superimposed on frontal bone (see Fig. 6–64)

•

•

•

B

Figure 6–67. (A) PA mandible. (B) Axiolateral mandible, projects body, and ramus for visualization. (Photo Contributor: Stamford Hospital, Department of Radiology.)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

A

167

B

Figure 6–68. (A) Radiograph demonstrates the oblique lateral projection of the TMJ in the closed-mouth position. (B) The open-mouth position. (Photo Contributor: Stamford Hospital, Department of Radiology.)

Paranasal Sinuses. T ere are our paired paranasal sinuses: rontal, ethmoidal, maxillary, and sphenoidal (Fig. 6–69); they vary greatly in their size and shape. T e le and right rontal sinuses are usually asymmetrical. T ey are located behind the glabella and superciliary arches o the rontal bone. T e rontal sinuses are not present in young children and reach their adult size in the 15th or 16th year. T e ethmoidal sinuses are composed o 6 to 18 thin-walled air cells that occupy the bony labyrinth o the ethmoid bone. T e ethmoidal sinuses o children are very small and do not ully develop until a er the 14th year. T e maxillary sinuses (maxillary antra/antra o Highmore) are the largest o the paranasal sinuses and are located in the body o the maxillae. T e maxillary antra are particularly prone to in ection and collections o stagnant mucus. T e maxillary antra reach their adult size around the 12th year. T e sphenoidal sinuses are located in the body o the sphenoid bone and are usually asymmetrical. T ey generally reach adult size by the 14th year. Radiography o the paranasal sinuses must be per ormed in the erect position so that any uid levels may be demonstrated and to distinguish between uid and other pathology such as polyps. TABLE6–41. The Temperomandibular Joint (TMJ) TMJ

Position o Part

AP axial (Towne)

• •

AP, MSP mid-IR OML table

Central Ray Directed •

30º caudad, enters ≈3″ above nasion

Structures Included/Best Seen •

•

Lateral (Schüller)

• • •

Axiolateral (Law)

• •

Skull MSP grid Interpupillary line vertical IOML transverse axis of IR

•

Skull MSP and IOML grid Rotate MSP down 15º toward grid

•

25º caudad, exiting lowermost TMJ

•

15º caudad, enters 1½″ superior to uppermost EAM, exiting lowermost TMJ

•

•

•

AP axial proj of condyloid processes and their articulations Unless contraindicated, another exposure is made with the mouth open (Fig. 6–68) Axiolateral TMJ Unless contraindicated, a second exposure is made with the mouth open Axiolateral TMJ of side down Unless contraindicated, a second exposure is made with the mouth open

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PART II IMAGING PRO CEDURES

1 2 3 4

Hyoid bone

Ante rio r view o f s kull

Late ral view o f s kull

Figure 6–69. The paranasal sinuses, AP and lateral views. Frontal sinuses (1), Ethmoid sinuses (2), Sphenoid sinuses (3), Maxillary sinuses (4).

o demonstrate air/ uid levels, the CR must always be directed parallel to the oor, even i the patient is not completely erect (just as in chest radiography). I the CR is angled to parallel the plane o the body, any uid levels will be distorted or actually obliterated (see able 6–42). TABLE6–42. The Paranasal Sinuses Paranasal Sinuses

Position o Part

PA axial (Caldwell)

• • •

Parietoacanthial (Waters)

• • • •

Central Ray Directed

Erect or seated PA Skull MSP and centered to grid Elevate chin to place OML 15º w/ horizontal

•

Erect or seated PA Skull MSP and centered to grid OML 37º to IR Centered to acanthion

•

to nasion

Structures Included/Best Seen •

•

enters parietal region and exits acanthion

•

•

PA axial of frontal and anterior ethmoid sinuses Petrous pyramids are seen in the lower one-third of the orbits (see Fig. 6–70) Parietoacanthial proj of maxillary sinuses Projected above petrous pyramids (see Fig. 6–71)

Note: Insu cient neck extension results in petrosae superimposed on oor of maxillary sinus; distorted projection of frontal and ethmoid. A modi cation of the parietoacanthiasl projection made with the mouth open will demonstrate the sphenoid sinuses through the open mouth. Lateral

• • • •

SMV (full basal)

• •

•

Erect or seated Skull MSP to IR Center 1″ posterior to outer canthus Interpupillary line vertical

•

mid-IR, enters 1″ posterior to outer canthus

•

Lat proj of all paranasal sinuses (see Fig. 6–72)

Erect or seated AP Neck hyperextended to place IOML IR CR and MSP IR

•

IOML and IR, enters MSP at level of sella

•

Basal proj of sphenoid and ethmoid sinuses Mandibular symphysis should be superimposed on frontal bone (see Fig. 6–73)

•

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

169

A

B

C

D

Figure 6–70. PA axial projection (Caldwell position) of the frontal and anterior ethmoid sinuses. The caudal angulation is somewhat excessive because the petrous pyramids are seen at the lowermost portion of the orbits. Correct angulation places the petrous pyramids in the lower one-third of the orbits. A, frontal sinuses; B, ethmoid air cells/sinuses; C, maxillary sinus; D, superior orbital ssure. (Photo Contributor: Stamford Hospital, Department of Radiology.)

A

B

Figure 6–71. Parietoacanthial projection (Water method). The sinuses are centered to the image receptor. The chin is adequately extended and the petrous pyramids are seen below the oor of the maxillary sinuses. The parietoacanthial projection provides a fore-shortened view of the frontal and ethmoid sinuses. In a modication of this projection, the sphenoid sinuses would be seen through the open mouth. A, frontal sinuses; B, maxillary sinus. (Photo Contributor: Stamford Hospital, Department of Radiology.)

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PART II IMAGING PRO CEDURES

Figure 6–72. Lateral projection of the paranasal sinuses. All paranasal sinuses are demonstrated on the lateral projection. (Photo Contributor: Stamford Hospital, Department of Radiology.)

Soft Tissue Neck. T e upper airway (Fig. 6–74 and able 6–43) can be examined in the AP and lateral positions. T ese projections are used to demonstrate hypertrophy o the pharyngeal tonsils or adenoids. It is desired to see the nasopharynx lled with air to provide adequate contrast; there ore, the exposure must be made on slow nasal inspiration.

Figure 6–73. SMVprojection of paranasal sinuses. Sphenoid and posterior ethmoid are demonstrated.

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171

C1 C2

P ha rynx Hyoid bone

C3 C4 C5

La rynx

C6

Tra che a

C7

S pinous proce s s

Tra che a l ca rtila ge rings

Figure 6–74. Anatomy of the neck, especially structures demonstrated in soft tissue study.

Figure 6–75. Lateral projection, soft tissue neck study (see Table 6–43).

TABLE6–43. The Upper Airway Upper Airway

Position o Part

AP

• •

Lateral

• •

Central Ray Directed

Structures Included/Best Seen

AP supine or erect MSP IR

•

to IR at level of EAM; expose on slow nasal inspiration

•

Air- lled nasopharynx/upper airway

Lateral, preferably erect MSP IR

•

to IR at level of EAM; expose on slow nasal inspiration

•

Air- lled nasopharynx/upper airway (Fig. 6–75)

COMPREHENSION CHECK Cong ratulations! You have completed a large portion of this chapter. If you are able to answer the following group of very comprehensive questions, you should feel confident that you have really mastered this section. You can refer back to the indicated pages to check your answers and/or review the subject matter. 1. Identify the bony structures comprising the axial skeleton; be prepared to discuss and answer questions relevant to anatomy and pathology of the axial skeleton, bone structure and development, characteristics, and articulations (pp. 133–136). 2. Describe the (a) method of positioning, (b) direction and point of entry of the CR, (c) principal structures visualized, and (d) pertinent traumatic and pathologic conditions and any technical adjustments they

may necessitate relative to the axial skeleton, to include routine and special views of the A. Cervical spine (p. 142) B. Thoracic spine (p. 144) C. Lumbar spine (p. 146) D. Sacrum, coccyx (p. 148, 150) E. Scoliosis series (p. 150) F. Sternum and SC jts (p. 151) G. Cranium (p. 161) H. Orbits and facial bones (p. 164) I. Zygomatic arches and nasal bones (p. 165) J. Mandible and TMJ’s (p. 166, 167) K. Paranasal sinuses (p. 168) L. Upper airway (p. 171)

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PART II IMAGING PRO CEDURES

BODYSYSTEMS Respiratory System Introduction. T e respiratory system includes the nose, pharynx (throat), larynx (voice box), trachea (windpipe), bronchi, and lungs. T e nose, pharynx, and larynx make up the upper respiratory system (Figs. 6–74 and 6–75), while the trachea, bronchi, and lungs make up the lower respiratory system. T e unctions o the respiratory system include supplying oxygen to the blood and relieving the body o carbon dioxide (Fig. 6–76). Pulmonary unction depends on the processes o ventilation and alveolar gas exchange. T e external openings o the nose are the nostrils, or nares; its internal/ posterior openings are the choanae or internal nares. T e external visible portion o the nose consists o hyaline cartilage, muscle, and skin—while its inner sur ace is lined with mucous membrane and receives ol actory nerve endings or the sense o smell. T e internal nose structures unction to warm, moisten, and lter incoming air and to detect smell. T e pharynx is divided into three portions: the nasopharynx, the oropharynx, and the laryngopharynx. T e pharynx is just posterior to the oral cavity; it begins at the choanae and terminates at the level o the cricoid cartilage. T e pharynx unctions as part o the digestive system, as well as the respiratory system, because it serves as passageway or both ood and air. As part o the digestive system, the pharynx aids in deglutition (swallowing); it also houses the pharyngeal tonsils, which have immunologic unctions. T e auditory tubes open into the nasopharynx; the oropharynx and laryngopharynx are the pharyngeal portions common to both the respiratory and digestive systems; the laryngopharynx opens into the larynx anteriorly and the esophagus posteriorly.

La rynx Tra che a S upe rior lobe right lung Horizonta l fis s ure Middle lobe bronchus

S upe rior lobe le ft lung S upe rior lobe bronchus Infe rior lobe bronchus Oblique fis s ure

Middle lobe right lung Oblique fis s ure

Infe rior lobe le ft lung

Infe rior lobe bronchus Infe rior lobe right lung

Figure 6–76. Trachea and bronchi (anterior view).

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

T e larynx lies in the anterior neck at about the level o C4 to C6; it connects the laryngopharynx and trachea. T e laryngeal walls are composed o nine cartilages. T ree o the cartilages are single/unpaired; they are the thyroid cartilage, the epiglottis, and the cricoid cartilage. T ree o the cartilages are paired: the arytenoid, the cunei orm, and the corniculate cartilages. T e paired cartilages are principally concerned with speech. T e thyroid cartilage, also re erred to as the laryngeal prominence or Adam’s Apple, is the most superior cartilage and orms the anterior laryngeal wall. T e epiglottis is a lea -shaped (elastic) cartilage that covers the glottis (vocal olds) during deglutition. T e cricoid (hyaline) cartilage is the most in erior o the nine cartilages; incision or emergency tracheotomy is made just below the cricoid cartilage. T e trachea (windpipe) is a cylindrical cartilaginous tube, approximately 4½″ in length, extending rom the larynx (approximately C6) to the primary bronchi (approximately 5). Its ciliated mucosa unctions to protect against mucus, dust, and pathogens. T e trachea is ormed by 16 to 20 C-shaped cartilaginous (hyaline) rings that can be palpated through the skin o the anterior neck. At about the level o 5, the trachea divides into the right and le mainstem, or primary, bronchi; at the bi urcation is a ridge called the carina, which separates the openings o the primary bronchi. T e right main bronchus is wider and more vertical; there ore, aspirated oreign bodies are more likely to enter it than the le main bronchus, which is narrower and angles more sharply rom the trachea. Each mainstem bronchus opens into the hilum o the corresponding lung. T e right lung is shorter because the liver is below it; the le lung is narrower because the heart occupies a portion o the lung’s le side. T e lungs have a somewhat conical shape; their narrow upper portion is called the apex, and their wide base is de ned by the diaphragmatic surace. Structures such as the mainstem bronchi and pulmonary artery and veins enter and leave the lungs at the hilum. T e right lung has three lobes; the upper and middle lobes are separated by the horizontal ssure, and the middle and lower lobes are separated by the oblique ssure. T e le lung has two lobes; the upper and lower lobes are separated by the oblique ssure (Fig. 6–76). T e lungs are enclosed in a serous membrane, the parietal pleura. T e visceral pleura lines the inner thoracic wall and covers the superior sur ace o the diaphragm; the potential space between the two layers o pleura is the pleural cavity. Pneumothorax is the presence o air in the pleural cavity. 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 af 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. One o the most diagnostically use ul and requently per ormed radiographic examinations is the chest x-ray examination. During the course o their illness and recovery, patients o en need successive chest examinations to monitor their progress, and reproduction o quality images is an important part o quality control. Accurate positioning and selection o technical actors is critical to the diagnostic value o the radiographic images (Fig. 6–77A). Even slight rotation or leaning can

Divisions o Pharynx

• • •

Nasopharynx Oropharynx Laryngopharynx

Laryngeal Cartilages (9) Three single/unpaired:

• • •

Thyroid Epiglottis Cricoid

Three paired:

• • •

Arytenoid Cuneiform Corniculate

173

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PART II IMAGING PRO CEDURES

Ape x of lungs Cla vicle

Tra che a

Aortic a rch

La te ra l borde r of s ca pula

He a rt Ba s e of lungs re s t on the dia phra gm

Cos tophre nic a ngle

A

B

Figure 6–77. (A) Normal PA chest image. Accurate positioning and selection of technical factors is critical to the diagnostic value of the radiographic image. (From Peart O. Lange Radiographic Positioning Flashcards. New York, NY: McGraw-Hill Education; 2014.) (B) Mobile AP chest radiograph. Observe an endotracheal tube and ECG leads, one chest tube on the right and two on the left. The patient has extensive soft-tissue emphysema. Radiographers must exercise particular care when working around various patient tubes. From the American College of Radiology Learning File. (Photo Contributor: ACR.)

cause signi cant distortion o the size and shape o the heart. Consistent and accurate positioning is essential to radiographic quality. T e radiographer must take care ul note o each patient’s apparel, body type, and clinical in ormation. Important considerations include removal o any radiopaque clothing and accessories, placing the IR transversely or broad-chested individuals (in order to include the costophrenic angles—blunting o the costophrenic angles is o en a result o pleural e usion), instructing emale patients with large breasts to move them up and laterally or the PA projection, exposing on the second inspiration or hypersthenic individuals, and adjusting exposure actors or various pathologic conditions. Appropriate radiation protection measures must always be provided. Mobile chest radiography o en brings the radiographer into contact with seriously ill patients. T e radiographer must be very cautious when positioning these patients or there are o en numerous tubes (e.g., chest tubes, endotracheal tubes, electrocardiographic [ECG] leads, Swan–Ganz lines, urinary catheters) associated with maintaining the patient’s airway or rein ating a collapsed lung, removing uid or air rom the pleural cavity, administering medications, measuring central venous pressure, or measuring urine output (Fig. 6–77B). T e variety o wires and/or tubes can inter ere with visualization o anatomic structures needed or optimum diagnostic value. Whenever possible, and with appropriate knowledge and caution, it is help ul to have these moved away rom areas o interest. ables 6–44 and 6–45 provide a summary o routine projections and requently per ormed special projections. Airway. AP and lateral projections o the airway and larynx are occasionally required to rule out oreign body, polyps, tumors, or any other condition suspected o causing some airway obstruction.

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175

TABLE6–44. The Chest: PAand Lateral Chest

Position o Part

PA

• •

•

Erect PA, MSP exactly IR Shoulders depressed and rolled forward w/ back of hands on hips Top of IR 1.5–2″ above shoulders

Central Ray Directed •

T7

Structures Included/Best Seen • •

• •

PA proj of thoracic viscera and skeletal anatomy Inspiration demonstrates air- lled trachea and lungs, 10 posterior ribs Expiration shows pulmonary vascular markings Inspiration and expiration are done for pneumothorax, foreign body, diaphragm excursion, and atelectasis (Fig. 6–78A)

Notes: • Chest radiography is performed erect whenever possible to demonstrate air/ uid levels • The MSP must be exactly vertical; any rotation can cause signi cant distortion and misrepresentation of the visceral structures (see Fig. 6–79A) • Rotation is detected on the PA image by asymmetrical distance between the sternal ends of the clavicles and the center of the adjacent thoracic vertebral body. • Shoulders are rolled forward to remove the scapulae from superimposition on the lung elds. • Superiorly, the pulmonary apices must be seen; inferiorly the costophrenic angles must be seen in their entirety. • Inspiration must be adequate to demonstrate 10 posterior ribs. • A72” SID is recommended to decrease magni cation of the heart. • Oblique projections of the chest are occasionally performed as supplemental views. The LAO and RAO positions are performed with the MSP at 45° to the IR. Lateral

• • •

Erect L lat, MSP IR Arms over head Top of IR 1.5–2”above shoulders

•

IR, enters at level of T7

•

Lat proj of chest particularly useful for heart, aorta, L lung and its ssures, and other left-sided structures/pathology; L lat usually done to place heart closer to IR (Fig. 6–78B)

Notes: • MSP must be exactly vertical; any lateral leaning can cause signi cant distortion and misrepresentation of the visceral structures • Rotation is detected on the lateral radiograph by superimposition of ribs on sternum or vertebrae. • Pulmonary apices and angles must be visualized (see Fig. 6–79B).

TABLE6–45. The Chest: Axial and Decubitus Chest

Position o Part

AP axial (lordotic)

• •

Erect AP MSP mid-IR at level of T2

Central Ray Directed •

15–20° cephalad to T2

Structures Included/Best Seen •

•

Decubitus (L and R lat)

•

•

•

Recumbent lat on a ected or una ected side as indicated by hx Anterior or posterior surface adjacent to IR. MSP mid-IR w/ top of IR 1.5” above shoulders

•

mid-IR

• •

AP axial (lordotic) proj of pulmonary apices projected below clavicles Can also be done with patient leaning back and CR IR Frontal (AP or PA) proj of the chest Useful for demonstration of air or uid levels

Note: If free air is suspected, the a ected side must be up; if uid is suspected, the a ected side must be placed down.

176

PART II IMAGING PRO CEDURES

A

B

Figure 6–78. (A) PA projection of the chest. Identify the lettered structures. A, costophrenic angle; B, clavicle; C, diaphragmatic domes; D, pulmonary apices; E, scapula; F, rib—8th posterior; G, air- lled trachea; H, 4th rib—axillary portion; I, heart; a, 6th rib; b, axillary portion—8th rib; c, vertebral/ oating rib. (B) Lateral projection of the chest. A, sternum; B, intervertebral foramen; C, apex of heart; D, heart; E, thoracic vertebra; F, pulmonary apices; G, hilar region; H, air- lled trachea; I and J, L and R hemidiaphragms. (Photo Contributor: Bob Wong, RT.)

L

L

A

B

Figure 6–79. (A) PA projection of the chest of a normal, healthy adult demonstrating the importance o positioning accuracy. Slight rotation has made the manubrium visible at the site of the right sternoclavicular joint, providing a density very similar to that created by a paraspinous or mediastinal mass. (B) Lateral projection of the same chest and without rotation. The sternum is seen free of superimposed ribs; the thoracic and lumbar vertebral spinous processes are seen. (From the American College of Radiology Learning File. Photo Contributor: ACR.)

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177

T e AP is positioned as or an AP cervical spine with the CR perpendicular to the laryngeal prominence. T e lateral is positioned as or a lateral cervical spine and centered to the coronal plane passing through the trachea (anterior to the cervical spine) at the level o the laryngeal prominence. Exposures are made on slow inspiration to visualize air- lled structures. Depending on the structure(s) o interest being examined, these positions may be per ormed with barium and/or during per ormance o the Valsalva/ modi ed Valsalva maneuver. Phonation o vowel sounds can help demonstrate more superior structures such as the larynx and/or vocal cords. Terminology and Pathology. T e ollowing is a list o radiographically signi cant conditions and devices with which the student radiographer should be amiliar: • • • • • • •

Asthma Atelectasis Bronchiectasis Bronchitis Central venous pressure line Chest tube (see Fig. 6–77) Chronic obstructive pulmonary disease • Cystic brosis • Dextrocardia (see Fig. 6–80) • Emphysema (see Figs. 6–77 and 6–81)

• Empyema • Endotracheal tube (see Fig. 6–77) • Hemothorax • Hickman catheter • Pneumoconiosis • Pneumonia Pneumothorax • Swan–Ganz catheter • T oracentesis • uberculosis

Figure 6–80. PA chest radiograph demonstrating the characteristic irreversible trapping of air found in emphysema, which gradually increases and overexpands the lungs, thus producing the characteristic attening o the diaphragm and widening o the intercostal spaces. The increased air content of the lungs requires a compensating decrease in technical factors.

178

PART II IMAGING PRO CEDURES

L

Figure 6–81. PA chest radiograph demonstrating dextrocardia. Dextrocardia is often associated with other heart defects.

Biliary System

Figure 6–82. Illustration of main hepatic and biliary ducts, gallbladder, and pancreas within the duodenal loop.

Introduction. T e biliary tree consists o the le and right hepatic ducts, common hepatic duct, cystic duct, common bile duct, and the gallbladder (GB) (Fig. 6–82). T e hepatic ducts leave the liver and join to orm the common hepatic duct. T e short cystic duct continues to the GB. T e common hepatic and cystic ducts unite to orm the long common bile duct, which joints with the pancreatic duct to orm the short hepatopancreatic ampulla (o Vater). he ampulla opens into the descending duodenum through the duodenal papilla that is surrounded by the hepatopancreatic sphincter (o Oddi). T e gallbladder is located in a shallow ossa on the in erior sur ace o the liver between its right and quadrate lobes. Small gallstones are able to pass out the GB through the cystic duct; those that are too large irritate the GB mucosa, resulting in cholecystitis. Gallstones can also lodge in ducts. I a stone lodges in the cystic duct, cholecystitis without jaundice is the result, because bile can still drain into the duodenum. A stone lodged in the common bile duct will result in jaundice as well as cholecystitis. A “gallbladder attack” is the pain ul result o atty chyme stimulating the release o cholecystokinin, which elevates pressure within the stone-laden GB. T e gallbladder o the average-build patient is located between the 10th and 12th ribs on the right, midway between the vertebral column and lateral border o the body. In hypersthenic individuals it is usually ound approximately 2″ higher and more lateral, while in asthenic individuals it is usually 2″ lower and more midline. In the erect position, the GB o an asthenic patient can be as low as the iliac ossa. Radiographic examinations o the biliary system ( able 6–46) no longer includes oral cholecystography; however, operative cholangiography, -tube cholangiography, and endoscopic retrograde cholangiopancreatography (ERCP) are o en per ormed. Each o these examinations requires the use o a contrast agent. With the exception o the ERCP, ew o these examinations are per ormed today, but rather are imaged via sonography (Fig. 6–83).

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

A

179

B

Figure 6–83. (A) A sonogram of the gallbladder demonstrating the presence of gallstones. (Photo Contributor: Stamford Hospital, Department of Radiology.) (B) MR image (Coronal T2) of biliary system. (Photo Contributor: Conrad P. Ehrlich, MD.)

Operative cholangiography is used to examine the bile ducts and requently ollows a cholecystectomy. An iodinated contrast agent is introduced into the common bile duct to evaluate biliary patency and that o the hepatopancreatic ampulla. Any calculi can be detected and removed be ore completion o surgery. Occasionally, a -shaped tube is le in the common bile duct or postsurgical drainage. -tube cholangiography is per ormed by injecting a contrast agent through the tube to detect any remaining calculi and evaluate the biliary tree patency. ERCP is a specialized procedure used to evaluate suspected biliary and/or pancreatic conditions. An endoscope is passed through the mouth, esophagus, and stomach, and into the descending duodenum to the ori ce o the hepatopancreatic ampulla. Following canalization o TABLE6–46. Surgical and ERCP Imaging Surgical Cholangiography

Position o Part

AP

•

Supine

Central Ray Directed •

center of IR

Structures Included/Best Seen • •

AP of biliary tree and gallbladder area To evaluate the hepatopancreatic ampulla and biliary tree for calculi or other pathology (following injection of contrast into common bile duct) (Fig. 6–84C)

Note: Can be performed RPO with L side elevated 15° to 20° and R upper quadrant centered to grid. ERCP

Position o Part

AP LPO

• •

Recumbent part LPO

Central Ray Directed •

biliary tree/CBD

Structures Included/Best Seen •

•

•

Fluoroscopy and spot images to evaluate biliary tree Contrast media injected through hepatopancreatic ampulla of Vater Rotation of part/equipment required to visualize entire biliary tree

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PART II IMAGING PRO CEDURES

A

B

C

Figure 6–84. (A) PA projection of GB (with gallstones). (B) LAO of the same GB. Oblique position moves GB away from vertebrae. (C) T-tube cholangiogram. (Photo Contributor: Stamford Hospital, Department of Radiology.)

the hepatopancreatic ampulla, uoroscopic images are made in the AP and/or LPO positions. Contrast material is injected into the common bile duct or evaluation o the biliary system. able 6–47 addresses surgical and ERCP imaging. Imaging procedure should immediately ollow injection, since, under normal conditions, contrast will empty rom the biliary ducts in approximately 5 minutes (Fig. 6–85). Terminology and Pathology. T e ollowing is a list o radiographically signi cant conditions with which the student radiographer should be amiliar: • Cholecystitis • Hepatitis • Cholelithiasis

• Jaundice • Cirrhosis • Pancreatitis

Digestive System Introduction. T e major portion o the GI tract lies within the abdominopelvic cavity. Its principal unctions are the chemical breakdown and TABLE6–47. Swallowing/Deglutition Dysfunction Study Swallowing

Position o Part

Lat

•

AP

•

Erect, upper esophagus centered to grid Erect, upper esophagus centered to grid

Central Ray •

•

grid

grid

Structures Included/Best Seen

•

Fluoroscopic images to demonstrate deglutition mechanism in cases of dysphagia, aspiration, globus sensation Lateral is single best proj.

•

AP proj used to check for symmetry

•

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

absorption o nutrients. T e digestive system (Fig. 6–86A and B) consists o the gastrointestinal (GI) tract and accessory organs. T e gastrointestinal tract, or alimentary canal, is a continuous tube o varying dimensions consisting o the esophagus, stomach, and small and large intestines. T e teeth, tongue, salivary glands, liver, gallbladder, and pancreas are accessory organs that aid in the mechanical and chemical breakdown o ood. T e lobulated salivary glands encircle the entrance to the oropharynx. T e largest o the salivary glands is the parotid gland. T e parotid is located just anterior to the ear and above the mandibular angle and is emptied by Stenson duct. T e submandibular glands are located near the inner sur ace o the mandibular body and empty their digestive juices into the mouth via Wharton duct. T e sublingual gland is located in the oor o the mouth and opens into the mouth by way o multiple ducts o Rivinas—the largest o these is Bartholins duct. Salivary glands can be investigated radiographically (termed sialography) via injection o (water soluble iodinated) contrast material or demonstration o glandular disorders such as tumors, calculi, or stula ormation ollowing trauma to the area. Sialography involves cannulation o the ostium o the parotid duct (Stenson) or the submandibular duct (Wharton). Figure 6–87 illustrates submandibular sialography. T e esophagus unctions to propel a ood bolus toward the stomach through peristaltic motion. T e cardiac sphincter is located at the distal end o the esophagus. “Heartburn” is an in ammation o the esophageal mucosa as a result o gastric re ux o acidic material into the esophagus. Esophageal varices are dilated, tortuous veins directly beneath the esophageal mucosa. A hiatal hernia is a herniation o the stomach through the esophageal hiatus o the diaphragm, producing a sac-like dilatation above the diaphragm (Fig. 6–88A and B). T e presence o re ux, varices, or herniation can be detected radiographically with the use o barium sul ate. From the lower esophagus through the anal canal, the GI tract has the same our tissue layers. T e innermost lining layer is the mucosa; mucous membranes line cavities that directly open to the exterior. T is mucous membrane is composed o a layer o epithelium, whose cells are shed and are replaced every ve to seven days. T e two other layers o the mucosa are the lamina propria and a thin muscular layer. T ey assist, respectively, in immunity and in orming gastric olds (rugae). T e submucosa is highly vascular (blood and lymphatic vessels), contains a broad complex o neurons, and can also include glands and lymphatic tissue. T e muscular layer o structures through the esophagus consists o skeletal muscle, which permits the voluntary muscular actions o chewing and swallowing. Skeletal muscle is also ound at the anal sphincter, permitting de ecation. T e remainder o the GI tract muscular layer is smooth/involuntary muscle that unctions to mix and propel digestive secretions and ood content. T e serosa/serous membrane is the outermost layer o the GI tract. Serous membranes line body cavities and covers organs that do not directly open to the exterior. Serous membranes produce a lubricating serous uid that allows organs to glide over one another without riction. T e serous membrane o the thoracic cavity is the double-walled pleura; the serous membrane o the abdominal cavity is the double-walled peritoneum.

181

Figure 6–85. Fluoroscopic image of a normal ERCP. The pancreatic and common bile ducts are clearly delineated. (Photo Contributor: Stamford Hospital, Department of Radiology.)

GI Tract Tissue Layers Inner to Outer:

• • • •

Mucosa Submucosa Muscular Serosa

Five Major Peritoneal Folds

•

Greater Omentum: an apron of fat over transverse colon and small bowel

•

Lesser Omentum: suspends stomach and duodenum from liver; contains some biliary vessels

•

Mesentery: binds jejunum and ileum to posterior abdominal wall; fan-shaped

•

Mesocolon: binds transverse and sigmoid colon to posterior abdominal wall

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PART II IMAGING PRO CEDURES

Tongue

Pa rotid gla nd Pa rotid (S te ns e n) duct P ha rynx

S ublingua l S ubma xilla ry

S a liva ry gla nds

Es opha gus

Right lobe of live r

Fundus of s toma ch

Le ft lobe of live r

S ple e n

Ga llbla dde r

Body of s toma ch Pa ncre a s

P ylorus

Le ft colic flexure Right colic flexure As ce nding colon

Tra ns ve rs e colon De s ce nding colon S ma ll inte s tine s (duode num, je junum a nd ile um)

Ce cum Appe ndix

Re ctum A

Ba rium-fille d s toma ch Ga llbla dde r Porta l ve in Pa ncre a s IVC Le ft a dre na l gla nd Aorta S ple e n Le ft kidney Right kidney Live r B

Figure 6–86. (A) The digestive system. (B) Axial CT image of the abdomen demonstrating many digestive and circulatory structures.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

Figure 6–87. Submandibular sialogram. (Photo Contributor: Stamford Hospital, Department of Radiology.)

T e peritoneum has an outer parietal layer that lines the abdominal cavity. Its inner visceral layer is re ected over and between the abdominal organs orming large olds between the viscera; these olds attach the organs to the abdominal cavity and to each other. T ese olds also house nerves, and blood and lymphatic vessels. T ere are ve major peritoneal olds: the greater omentum, the lesser omentum, the mesentery, the alci orm ligament, and the mesocolon.

Es opha gus

Dia phra gm

P rotrus ion of s toma ch through dia phra gm Es opha ge a l ga s tric juncture No rmal po s itio n A

Hiatal he rnia B

C

Figure 6–88. (A) Normal position of the stomach. (B) Note protrusion of stomach through esophageal hiatus (hiatal hernia). (C) Esophagram demonstrating hiatal hernia (with Schatzki ring). (Photo Contributor: Stamford Hospital, Department of Radiology.)

183

184

PART II IMAGING PRO CEDURES

Fundus Ca rdia c ope ning

A B

Le s s e r curva ture

E

Duode na l bulb Gre a te r curva ture

C

D

Ruga e

P yloric s phincte r P ylorus A

B

Figure 6–89. (A) Stomach (internal aspect). (B) Barium-filled duodenal loop; duodenal bulb, descending, transverse, and ascending duodenum are well demonstrated. A, duodenal bulb; B, pyloric valve; C, ascending duodenum; D, transverse duodenum; E, descending duodenum. (Photo Contributor: Stamford Hospital, Department of Radiology.)

Salivary Glands and Their Ducts

• • •

Parotid: Stenson Duct Submandibular: Wharton Duct Sublingual: Bartholin Duct

Stomach

• • •

Fundus Body Pylorus

T e stomach is the dilated, sac-like portion o the GI tract. When the stomach is empty, its mucosal lining orms so olds called rugae (Fig. 6–89A). Gastritis is an in ammation o the gastric mucosa that can be caused by excessive secretion o acids or by ingestion o irritants such as aspirin or corticosteroids. Exteriorly, it presents a greater curvature on its lateral sur ace and a lesser curvature on its medial sur ace. T e proximal opening o the stomach, at the gastroesophageal junction (GEJ), is the cardiac sphincter; the pyloric sphincter is located at its distal end. T e portion o the stomach around the distal esophagus is called the cardia; that portion superior to the esophageal juncture is the undus. T e sharp angle between the esophagus and undus is the cardiac notch. T e major portion o the stomach is the body; the distal portion is the pylorus. T e incisura angularis is located on the lesser curvature and marks the beginning o the pylorus. T e distal portion o the pylorus is marked by the pyloric sphincter. T e small intestine is composed o the duodenum, jejunum, and ileum. T e duodenum is the shortest portion. It begins just beyond the pyloric sphincter and is divided into our portions: the duodenal cap or bulb, descending duodenum, transverse duodenum, and ascending duodenum. T ese portions orm a C-shaped loop (duodenal loop) that is occupied by the head o the pancreas (Fig. 6–89B). T e descending portion receives the hepatopancreatic ampulla and duodenal papilla (see “Biliary System” section). T e ascending portion terminates at the duodenojejunal exure (angle o reitz). While the position o the short (9″) duodenum is xed, the jejunum (9 ) and ileum (13 ) are very mobile. wisting o the small intestine is called volvulus and can cause compression o blood vessels, leading to loss o blood supply, ischemia,

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

He pa tic flexure

185

S ple nic flexure As ce nding colon

Tra ns ve rs e colon

Ile oce ca l va lve

De s ce nding colon

As ce nding colon Te nia e coli

Ha us tra

Ile um

Fre nulum

Ce cum Appe ndix

Ce cum

S igmoid colon

Ile um Orifice of a ppe ndix

Re ctum

A

Appe ndix

B

Figure 6–90. (A) The colon. (B) The ileocecal valve.

and in arct o the a ected area. T e small intestine terminates at the ileocecal valve. T e lengths o intestine usually quoted are those present at autopsy and can be up to 50% longer than actual size because o loss o muscle tone ollowing death. T e approximately 5- -long large intestine (colon) (Fig. 6–90A) unctions in the ormation, transport, and evacuation o eces. T e colon begins at the terminus o the small intestine; its rst portion is the dilated sac-like cecum, located in erior to the ileocecal valve (Fig. 6–90A and B). Projecting posteromedially rom the cecum is the short (approximately 3.5″) vermi orm appendix. Its lumen is particularly narrow in adolescents and young adults and may become occluded by a ecalith and result in in ammation (appendicitis). T e ascending colon is continuous with the cecum and is located along the right side o the abdominal cavity. It bends medially and anteriorly in the right hypochondrium, orming the right colic (hepatic) exure. T e colon traverses the abdomen as the transverse colon and bends posteriorly and in eriorly in the le hypochondrium, orming the le colic (splenic) exure. T e descending colon continues down the le side o the abdominal cavity and, at about the level o the pelvic brim, the colon moves medially to orm the S-shaped sigmoid colon. T e rectum is that part o the large intestine, approximately 5″ in length, between the sigmoid and the anal canal. Diverticula are small saccular protrusions o intestinal mucosa through the intestinal wall. T ey are most commonly associated with the sigmoid colon and can become occluded by ecaliths and subsequently in amed (diverticulitis). I an in amed diverticulum per orates, it can result in severe bleeding and peritonitis. Patient Preparation. Preliminary patient preparation is generally required o patients undergoing radiographic examinations o various

Small Intestine

• • •

Duodenum: approx 10”(9–12”at autopsy)) Jejunum: approx 3–6’(up to 9’at autopsy) Ileum: approx 6–12’(up to13’at autopsy)

Large Intestine (approximately 5 t)

• • • • • •

Cecum Ascending colon Transverse colon Descending colon Sigmoid colon Rectum

186

PART II IMAGING PRO CEDURES

portions o the digestive system. T e upper GI tract (stomach and small intestine) must be empty and the lower tract (large intestine) must be cleansed o any gas and ecal material. Patients should be questioned about their preparation and a preliminary “scout” image taken to check abdominal contents and or any radiopaque (e.g., gallstones, residual barium) material. o make up or the lack o subject contrast, radiography o the digestive system most o en requires the use o arti cial contrast media in the orm o barium sul ate suspension or water-soluble iodine and, requently, air. Double-contrast studies o the stomach and large intestine are requently per ormed. Barium sul ate unctions to coat the organ with radiopaque material, while air in ates the structure. T is permits visualization o the shape o the structure as well as visualization o pathology within its lumen. T us, conditions such as polyps can be seen projecting within the air- lled lumen. A barium- lled lumen would make visualization o anything but the organ shape virtually impossible. T e speed with which barium sul ate passes through the alimentary canal depends on patient habitus (hypersthenic usually astest) and the concentration o the barium suspension. When per orming examinations on patients suspected or known to have stomach or intestinal per oration, water-soluble iodinated contrast media should be used instead o barium sul ate. I the water-soluble medium leaks through a per oration into the peritoneal cavity, it will simply be absorbed and excreted by the kidneys. Water-soluble contrast media are excreted more rapidly than are barium sul ate preparations. T ese studies are ar rom pleasant or patients and the radiographer should make every e ort to ully explain the procedure while endeavoring to expedite the examination and make the patient as com ortable as possible. With the increased use o digital uoroscopy, ewer “overhead” radiographs are done today. ables 6–48 through 6–51 provide a summary o the most requently per ormed positions/projections o the upper and lower GI tract. TABLE6–48. The Abdomen Abdomen

Position o Part

AP

• • •

Erect

• • •

Lateral Decubitus

•

Central Ray Directed to midline at level of crest

Structures Included/Best Seen

Supine MSP centered to grid IR centered to iliac crest (see Fig. 6–91)

•

AP erect MSP centered to grid IR centered ≈2″ above iliac crest

•

to mid-IR

•

AP erect proj used to demonstrate air/ uid levels; both hemidiaphragms should be included (see Fig. 6–92A and B)

Patient lat recumbent (AP or PA) MSP and centered to upright grid, cassette centered ≈2″ above iliac crest

•

Horizontal and mid-IR

•

Usually, le t lat decubitus of abdomen to demonstrate air/ uid levels in patients unable to assume the erect position; both hemidiaphragms should be included

•

•

AP proj often used as “scout” image preliminary to contrast studies Shows size and shape of kidneys, liver, and spleen, psoas muscles, as well as any calci cations or masses

Note: A dorsal decubitus can also be a valuable supplement to show air/ uid levels. The patient is placed in the dorsal decubitus (supine) position and a horizontal x-ray beam is used.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

187

Figure 6–91. AP projection of the abdomen. (Photo Contributor: Conrad P. Ehrlich, MD.)

A

B

Figure 6–92. Abdominal pain is among the most common symptoms presented in an emergency department. Acute abdomen involves rapid onset of severe symptoms, and can be an indication of life-threatening intra-abdominal pathology. An acute abdomen survey, AP recumbent (A), AP erect (B) or L lateral decubitus, and erect PA chest are often used to evaluate possible obstruction or free air/ uid under the diaphragm/within the abdomen. Note the air levels seen in the upright abdomen (B) above.

188

PART II IMAGING PRO CEDURES

Figure 6–93. Small-bowel obstruction indicated by the dilated bowel loops having a ladder-like pattern. Patient is recumbent; therefore, air/ uid levels are not demonstrated. (Reproduced with permission from Doherty GM, ed. Current Surgical Diagnosis &Treatment, 12th ed. New York: McGraw-Hill, 2006:666.)

Abdomen. Abdominal pain is a common problem and is among the most common symptoms presented in an emergency department. T e term acute abdomen re ers to the rapid onset o severe symptoms, and can be an indication o li e-threatening intra-abdominal pathology. Causes o abdominal pain include appendicitis, intestinal obstruction, paralytic ileus, diverticulitis, peptic ulcer disease, gastroenteritis, pelvic in ammatory disease, and many others. Radiologic investigation is o en indicated. A three-way abdomen study (AP recumbent, AP erect, and L lateral decubitus) may be requested, or an acute abdomen survey (AP recumbent, AP erect or L lateral decubitus, and erect PA chest) to evaluate possible obstruction (Fig. 6–93) or ree air and uid within the abdomen/under the diaphragm (see able 6–48 and Fig. 6–92A and B). Patients with these conditions are most o en in severe pain and can experience severe nausea. T e radiographer must be caring, skilled, and ef cient. Esophagus. T e esophagus ( able 6–49) unctions to propel a ood bolus toward the stomach through peristaltic motion. T e cardiac sphincter, also known as the lower esophageal sphincter (LES), is located at the distal end o the esophagus. “Heartburn” is an in ammation o the esophageal mucosa as a result o re ux o acidic gastric material into the esophagus. Esophageal varices are dilated, tortuous veins directly beneath the esophageal mucosa. A hiatal hernia is herniation o a portion o the stomach through the diaphragm’s esophageal hiatus, producing a dilatation above the diaphragm (Fig. 6–88A and B). T e presence o re ux, varices, or herniation can be detected radiographically with the use o barium sul ate.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

189

TABLE6–49. The Esophagus Esophagus

Position o Part

AP

• • •

RAO

• • •

Lateral (L or R)

• • •

Central Ray Directed

Structures Included/Best Seen

Supine, MSP centered and table IR top 1–2″ above shoulders barium swallowed during (< 0.1 s) exposure)

•

mid-IR, ≈T6–T7

•

Barium- lled esophagus in AP proj

Prone obl, 35–40º RAO, IR top 1–2″ above shoulders barium swallowed during exposure

•

mid-IR, ≈T6–T7

•

Barium- lled esophagus in RAO proj Demonstrated b/w vertebrae and heart Best single proj of barium- lled esophagus (see Fig. 6–94)

Recumbent lat, MCP centered to grid top of IR just above shoulders barium swallowed during exposure

•

• •

mid-IR

•

Barium- lled esophagus in lat proj

Notes: • Esophagus for the demonstration of varices must be performed in the recumbent position; table slightly Trendelenburg and/or performance of the Valsalva maneuver is also helpful. • Exposure times of 0.1 second or less should be used to avoid motion. • Respiration normally stops during and shortly after the act of swallowing, so patients need not be instructed to stop breathing.

Stomach and Small Intestine. Radiologic examination o the stomach and/or small bowel generally begins with uoroscopic examination. T e uoroscopist observes the swallowing mechanism, mucosal lining (rugae) o the stomach, and the lling and emptying mechanisms o the stomach and proximal small bowel in various positions. T e patient is turned and rotated in various positions so that all aspects o the stomach and any abnormalities such as hiatal hernia (see Fig. 6–88C) can be visualized. Double-contrast examinations o the upper GI system are perormed requently. Occasionally, glucagon or another similar drug will be given to the patient (IV or IM) prior to the examination to relax the GI tract and permit more complete lling. Various images will be made by the uoroscopist and the radiographer may take supplemental “overhead” projections. Small-bowel series examinations require that successive images be made o the abdomen at speci ed intervals; an additional uoroscopic image is made when barium reaches the ileocecal valve. Contrast material (usually water soluble) may occasionally be instilled through a gastrointestinal (GI) tube or visualization o the GI tract. GI tubes can be used therapeutically to siphon gas and uid rom the GI tract or diagnostically, using contrast agent, to locate the site o obstruction or pathology (see able 6–50). Barium sul ate is contraindicated i a per oration is suspected somewhere along the course o the GI tract (e.g., a per orated diverticulum or gastric ulcer); a water-soluble (absorbable) iodinated contrast medium is generally used instead. A patient with a nasogastric (NG) tube can have the contrast medium administered through it or the purpose o locating and studying any site o obstruction. T is procedure is called enteroclysis. Large Intestine. T e lower GI tract is most o en examined by retrograde lling with barium sul ate and, requently, air. T e uoroscopist observes lling o the large bowel in various positions and makes images as indicated. Much o the barium is then drained rom the intestine, and air is introduced. T e objective is to coat the bowel with barium, then

Figure 6–94. RAO of a barium- lled esophagus. The esophagus has three normal constrictions at the levels of the cricoid cartilage, the left bronchus, and the esophageal hiatus of the diaphragm. (Photo Contributor: Stamford Hospital, Department of Radiology.)

190

PART II IMAGING PRO CEDURES

TABLE6–50. The Stomach and Small Bowel Stomach

Position o Part

LPO

• •

Supine, obliqued ≈40º to left Centered midway b/w vertebrae and L abdominal wall at level of L1

Central Ray Directed •

mid-IR (at level of L1)

Structures Included/Best Seen • •

Barium- lled fundus Good position for double contrast of body, pylorus, and duodenal bulb (see Fig. 6–95)

Note: As the fundus is the most posterior portion of stomach, it readily lls w/ barium in AP position and moves more superiorly. Lateral

• •

Recumbent lateral (usually R) Center m/w b/w MCP and anterior abdominal wall to IR at level of L2

•

mid-IR (at level of L2)

• •

Lat stomach and prox small bowel Demonstrates anterior and posterior aspects of stomach, retrogastric space, pyloric canal, and duodenal loop (see Fig. 6–96)

Note: This projection provides the best visualization of the pyloric canal and duodenal bulb in the hypersthenic patient. RAO

• •

PA

•

Recumbent PA obliqued 40–70º Centered m/w b/w vertebrae and lateral abdominal wall at level of L2

•

Prone, MSP centered to IR, at level of L2

•

mid-IR (at level of L2)

•

•

mid-IR (at level of L2)

• •

Right PA obl proj of stomach, barium- lled pyloric canal and duodenal loop Demonstrates stomach’s emptying mechanism, because peristaltic activity is greatest in this position PA proj of transversely spread stomach Demonstrates contours, greater and lesser curvatures (Fig. 6–97)

Note: Hypersthenic patients frequently have high, transverse stomachs with indistinguishable curvatures. The adult hypersthenic stomach can be “opened” and its contours made readily visible by angling the CR 35–45º cephalad. The top edge of a lengthwise 14″ × 17″ IR is placed level with the patient’s chin and the CR directed to mid-IR. Small Bowel AP/PA

• •

Supine, MSP centered to grid IR centered to level of L2

•

mid-IR

•

•

AP proj of dist esophagus area, stomach, and proximal small bowel Demonstrates hiatal hernias w/ patient in Trendelenburg position

Note: This position is used to record progress of the barium column in small bowel examinations. The rst radiograph is usually made 15 minutes after ingestion of the barium drink and centered at level of L2. Subsequent radiographs are made at 15- to 30-minute intervals (and centered at level of crest), according to the individual patient and how quickly or slowly the barium progresses. Spot images are usually taken when the barium column reaches the ileocecal valve.

D

E A F

Figure 6–95. LPO of the stomach. In this position, air replaces the barium that drains from the duodenal bulb and pylorus, thus providing double-contrast visualization of these structures. A, duodenal bulb; B, descending duodenum; C, transverse duodenum; D, fundus; E, body/gastric mucosa; F, pylorus; G, ascending duodenum. (Photo Contributor: Stamford Hospital, Department of Radiology.)

B G C

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

Figure 6–96. Lateral projection demonstrates the anterior and posterior stomach surfaces and the retrogastric space. (Photo Contributor: Stamford Hospital, Department of Radiology.)

Figure 6–97. PA projection of the stomach. Note barium in body and pylorus. (Photo Contributor: Stamford Hospital, Department of Radiology.)

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PART II IMAGING PRO CEDURES

distend its lumen with air. T e double-contrast method is ideal or demonstration o intraluminal lesions, such as polyps. T e success o the barium enema examination depends on several actors, but without proper patient preparation, a diagnostic examination is o en impossible. Poor preparation resulting in retained ecal material in the colon can mimic or conceal pathologic conditions. T e barium enema is most easily tolerated and retained by the patient i it is cool or actually cold (≈40–45°F). T ere is probably no radiographic examination that causes more embarrassment and anxiety than the barium-enema and air-contrast procedure. T e radiographer must be sensitive to the concerns and needs o the patient by providing a complete explanation o the procedure and by providing or the patient’s modesty as much as possible. able 6–51 summarizes requently per ormed BE projections taken ollowing the uoroscopic procedure.

TABLE6–51. The Large Intestine BE

Position o Part

AP

•

Supine, MSP centered to IR at level of iliac crest

Central Ray Directed •

mid-IR

Structures Included/Best Seen •

AP proj of entire contrast- lled large intestine

Notes: The large intestine of hypersthenic patients is high and around the periphery of the abdomen; hence, they may require that the AP and PA be done on (2) 14″ × 17″, IRs placed crosswise in the Bucky tray. In contrast, the colon of the asthenic patient is low, redundant, and more midline. PA

PA axial

•

•

Prone, MSP centered to IR at level of iliac

•

Prone, MSP centered to IR at level of pubic symphysis

•

mid-IR

• •

35º caudad to midline at level of ASIS

• •

PA proj of entire contrast- lled large intestine AP or PA erect may be used to demonstrate double-contrast exures PA axial proj of sigmoid colon Angulation opens the length of the S-shaped colon (see Fig. 6–98)

Note: AP axial may be performed to show similar structures; CR is directed 35° cephalad. RAO

•

•

LAO

• •

PA, obl ≈40º, centered to midline IR centered to level of iliac crest

•

PA obl ≈40º, centered to midline IR centered to level of iliac crest

•

mid-IR

• •

mid-IR

• •

Right PA obl proj of the colon Demonstrates ascending colon and hepatic exure (see Fig. 6–99) Left PA obl proj of the colon Demonstrates descending colon and splenic exure

Note: RPO will demonstrate descending colon and splenic exure; LPO will demonstrate ascending colon and hepatic exure. Lateral

•

•

Lateral Decubitus (R and L)

• •

•

Lat recumbent, MCP centered to grid IR centered at level of ASIS

•

Lat recumbent, (AP or PA) MSP and centered to upright grid At the level of iliac crest

•

mid-IR

• •

Horizontal and mid-IR

•

•

L or R lat proj Especially for rectum and rectosigmoid area Air rises to provide double-contrast delineation of lat walls of colon Both decubitus are routinely performed (see Fig. 6–100)

Note: A postevacuation PA or AP projection is usually performed to demonstrate large bowel mucosa.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

A

B

Figure 6–98. Double-contrast PA axial projection of the rectum and sigmoid. The caudal tube angulation serves to “open”the redundant S-shaped sigmoid colon. Similar results may be obtained in the AP position with a cephalad tube angle. A, descending colon; B, sigmoid colon. (Photo Contributor: Stamford Hospital, Department of Radiology.)

D

A E

F

B

C

Figure 6–99. RAO of the barium- and air- lled large bowel. Note that the hepatic exure is “opened”for better visualization. An LPO would provide similar results. The opposite obliques (LAO, RPO) are used to demonstrate the splenic exure and descending colon. A, right colic/hepatic exure; B, ascending colon; C, cecum; D, left colic/splenic exure; E, transverse colon; F, descending colon. (Photo Contributor: Stamford Hospital, Department of Radiology.)

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PART II IMAGING PRO CEDURES

Figure 6–100. Right lateral decubitus view of the air- and barium- lled colon. The heavier barium sulfate moves toward the dependent side, while air rises to ll the remainder of the barium-coated lumen. Thus, the right lateral decubitus demonstrates double contrast o the “le t-sided walls” o the ascending and descending colons (i.e., lateral side of descending colon and medial side of ascending colon). (Photo Contributor: Stamford Hospital, Department of Radiology.)

Terminology and Pathology. T e ollowing is a list o radiographically signi cant abdominal and digestive conditions and devices with which the student radiographer should be amiliar: • • • • • • • • • • •

Achalasia Appendicitis Ascites Colostomy Crohn disease Diverticulitis Diverticulosis Dysphagia Enteritis Esophageal re ux Esophageal varices

• • • • • • • • • • •

Gastroenteritis Hiatal hernia (see Fig. 6–88) Ileostomy Intussusception Irritable-bowel syndrome Peptic ulcer Peritonitis Polyp Pyloric stenosis Ulcerative colitis Volvulus

Urinary System Introduction. wo o the unctions o the urinary system (Fig. 6–101) are to remove wastes rom the blood and eliminate it in the orm o urine. T e tiny units within the renal substance that per orm these unctions are called nephrons. T e major components o the urinary system are the kidneys, ureters, and bladder.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

Kidney P roduce s urine Ure te r Tra ns ports urine towa rd urina ry bla dde r Urina ry bla dde r Te mpora rily s tore s urine prior to excre tion Ure thra Conducts urine to exte rior

Figure 6–101. Components of the urinary system.

T e paired kidneys are retroperitoneal and embedded in adipose tissue between the vertebral levels o 12 and L3. T e right kidney is usually 1″ to 2″ lower than the le because o the presence o the liver on the right. T e kidneys move in eriorly 1″ to 3″ when the body assumes an erect position; they move in eriorly and superiorly during respiration. T e slit-like opening on the medial concave sur ace o each kidney is the hilum, which opens into a space called the renal sinus (Fig. 6–102). T e renal artery and vein, lymphatic vessels, and nerves pass through the hilum. T e upper, expanded portion o the ureter is called the renal pelvis, or in undibulum, and also passes through the hilum; it is continuous with the major and minor calyces within the kidney. Within each kidney, the renal parenchyma is divided into two parts: the outer cortex and inner medulla. T e cortex is compact and has a grainy appearance as a result o the many glomeruli within its tissues. T e medulla contains 10 to 14 renal pyramids with a characteristic striated appearance that is due to the collecting tubules within (see Fig. 6–102).

Cortex Me dulla

Ma jor ca lix

Re na l pa pilla e

Re na l column

Re na l s inus Ca ps ule Re na l pe lvis Minor ca lice s

Re na l pyra mid (me dulla ry pyra mid)

Ure te r

Figure 6–102. Section through the left renal pelvis.

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PART II IMAGING PRO CEDURES

Ure te r Mucos a l folds

Ure te ra l orifice

Trigone P ros ta te Inte rna l ure thra l orifice

Figure 6–103. Bladder trigone (anterior portion of bladder removed).

T e proximal portion o each ureter is at the renal pelvis. As the ureter passes in eriorly, three normal constrictions can be observed: at the ureteropelvic junction, at the pelvic brim, and at the ureterovesicular junction. T e ureters lie in a plane anterior to the kidneys; ureteral lling with contrast media is best achieved using the PA projection. Urine is carried through the ureters by peristaltic activity. I a ureter is obstructed by a kidney stone, hydronephrosis occurs. T e ureters enter the urinary bladder posteroin eriorly (Fig. 6–103). T e base o the bladder rests on the pelvic oor. T e triangular-shaped area ormed by the ureteral and urethral ori ces is called the trigone. Micturition is the process o emptying the urinary bladder o its contents through the urethra. T e male urethra is approximately 7″ to 8″ long and is divided into prostatic, membranous, and penile portions. T e emale urethra is approximately 1.5″ in length. A common complication o regional enteritis or diverticular disease is the ormation o a stula between the urinary bladder and small or large intestine. Fistulous tracts may o en be evaluated radiographically with contrast media. Routine radiographic procedures o the urinary system are generally per ormed via the IV route. When per ormed in the retrograde manner, cystoscopy is required. T ough the numbers o urinary system x-ray examinations have been steadily decreasing, and are in requently per ormed in many institutions today, a review o these examinations ollows.

Figure 6–104. A preliminary or “scout”image of the abdomen is taken before the start of an IVU. The radiograph is checked for residual barium from previous contrast studies, patient preparation (including barium from previous studies; note residual barium in patient’s appendix), location of kidneys, technical factors, and any calci cations. (Photo Contributor: Stamford Hospital, Department of Radiology.)

Patient Preparation and Procedure. Investigation o the urinary tract requires patient preparation suf cient to rid the intestinal tract o gas and ecal material. ypical preparation usually begins the evening be ore the examination with a light dinner, a gentle laxative, and nothing to eat or drink (NPO; non per os [nothing by mouth]) a er midnight. Immediately be ore beginning the IVU, the patient must be instructed to empty his or her bladder; this prevents dilution o opaci ed urine in the bladder. I the patient has a urinary catheter, it is generally clamped just be ore the injection and unclamped be ore the postvoid image. T e IVU is preceded by a preliminary scout image o the abdomen to evaluate patient preparation and reveal any calci cations (renal or gallstones), position o kidneys, and accuracy o technical actor selection (Fig. 6–104).

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

197

Because the urinary structures have so little subject contrast, arti cial contrast material must be employed or better visualization o these structures. Contrast agents used or urographic procedures can have unpleasant and (rarely) even lethal side e ects. Intravenous injection o contrast requently produces a warm, ushed eeling, a bitter or metallic taste, or mild nausea. T ese side e ects are o short duration and usually pass as quickly as they come. More serious side e ects include urticaria, respiratory discom ort and distress, and, rarely, anaphylaxis. An antihistamine is appropriate treatment or simple side e ects, but the radiographer must always be prepared to deal quickly and ef ciently with patients experiencing more serious reactions. Nonionic contrast agents are ar less likely to produce side e ects. Contrast agents and their side e ects are more thoroughly discussed in Chapter 1. T e selected contrast agent is injected intravenously and successive radiographs are made at speci ed intervals. A time-interval marker must be included on each image to indicate the elapsed postinjection time. Injection and postinjection protocol varies with the institution, radiologist, patient condition, and diagnosis. T e contrast may be rapidly injected in a bolus to obtain a 30-second nephrogram. Compression over the distal ureters (delaying contrast or urine travel to bladder) may be required to more completely ll the kidneys with contrast medium or to visualize the contrast- lled kidneys or a longer period o time (Fig. 6–105). Maximum concentration o the contrast

Figure 6–105. PA projection of IVU, demonstrating contrast- lled ureters. Since the ureters lie in a plane that is anterior to that of the kidneys, they are best demonstrated as contrast- lled structures in the PAposition. The contrast material, which is heavier than urine, gravitates to ll the anterior ureters. (Photo Contributor: Stamford Hospital, Department of Radiology.)

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PART II IMAGING PRO CEDURES

material usually occurs at 15 to 20 minutes a er injection, but varies with degree o patient hydration. Radiographs collimated to the kidneys (11″ × 14″ crosswise) may be required at 1, 3, and 5 minutes to evaluate a diagnosis o renal hypertension. Both obliques may be required to evaluate a suspected tumor or lesion. AP and oblique kidney, ureter, and bladder images (KUBs) are usually required at 10 to 15 minutes a er injection. A prone KUB is requently requested at 20 minutes. Because the ureters lie in a plane anterior to the kidneys, ureteral lling with contrast media is best achieved using the PA projection (see Fig. 6–106). Types of Examinations. Routine IV procedures are most correctly re erred to as intravenous urography (IVU), or excretory urography, although they are still commonly re erred to as intravenous pyelography (IVP) (pyel re ers only to renal pelvis). Intravenous procedures demonstrate unction o the urinary system. Retrograde studies demonstrate only the structure o the part and are generally per ormed to evaluate the lower urinary tract (lower ureters, bladder, and urethra).

Figure 6–106. This KUB is a 5-minute IVU image. Good collimation is evident and the kidneys, ureters, and bladder are included in their entirety. A, pubic symphysis; B, body, L3; C, renal pelvis; D, ASIS; E, iliac crest; F, ureter; G, greater trochanter; H, ischium; I, bladder; J, renal collecting system/calyces; K, renal cortex. (Photo Contributor: Bob Wong, RT.)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

Figure 6–107. When positioning the abdomen, it is important to position the patient’s hands at his or her side or resting high on the chest. Note the position of the patient’s right hand in this retrograde urogram. (From the American College of Radiology Learning File. Photo Contributor: ACR.)

Retrograde urograms (Fig. 6–107) require catheterization o the ureter(s). Radiographs that include the kidney(s) and ureter(s) in their entirety are made a er retrograde lling o the structures. A cystogram or (voiding) cystourethrogram requires urethral catheterization only. Radiographs are made o the contrast- lled bladder and requently o the contrast- lled urethra during voiding. Cystoscopy is required or location and catheterization o the vesicoureteral ori ces. Excretory and retrograde urography involve accurate positioning o the abdomen to include the kidneys, ureters, and bladder. I these structures cannot t on a single image, a second radiograph is generally taken or the bladder. ables 6–52 and 6–53 provide a review o abdomen/ KUB and bladder positioning or IVU examinations. TABLE6–52. The Kidney, Ureters, and Bladder (KUB) KUB

Position o Part

AP

• •

Supine, MSP centered to grid, IR centered to iliac crest

Central Ray Directed •

to midline at level of crest

Structures Included/Best Seen •

AP proj of abdomen shows size and shape of kidneys, liver, spleen, psoas muscles, and any calci cations or masses

Note: AP abdomen should include from top of kidneys through symphysis pubis (see Fig. 6–107); obliques are performed at 30°.

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PART II IMAGING PRO CEDURES

Figure 6–108. Voiding cystourethogram. (Photo Contributor: Stamford Hospital, Department of Radiology.)

he PA projection will best demonstrate contrast- illed ureters (see Fig. 6–107). T e 30º oblique KUB places the kidney o the up side parallel to the image receptor; the ureter o the side down parallel to the image receptor. Figure 6–109 is an RPO that places the le kidney and right ureter parallel to the image receptor.

TABLE6–53. The Bladder Bladder

Position o Part

AP

•

•

AP (Voiding Studies)

•

•

Central Ray Directed

Supine, MSP and centered to grid Lower edge of IR just below pubic symphysis

•

Supine, MSP and centered to grid IR centered to pubic symphysis

•

to center of IR

to midline at level of pubic symphysis

Structures Included/Best Seen •

AP proj shows contrast- lled or postvoid bladder

•

AP projection of bladder and proximal urethra Used for voiding cystourethrograms (see Fig. 6–108) A 5º caudad can be used for the female to place bladder neck and urethra below pubis

• •

Note: Oblique projections are obtained at 40–60° for the female and at 30° for the male.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

201

Figure 6–109. Fifteen-minute RPO during IVU, demonstrating the left kidney and right ureter parallel to the image receptor. The 30º oblique KUB places the kidney of the up side parallel to the image receptor, and the ureter of the side down parallel to the image receptor. (Photo Contributor: Stamford Hospital, Department of Radiology.)

Terminology and Pathology. T e ollowing is a list o radiographically signi cant urinary conditions and devices with which the student radiographer should be amiliar: • • • • • • • • • • • •

Cystitis Double-collecting system Double ureter Fistula Foley catheter Horseshoe kidney Hydronephrosis Hydroureter Incontinence Nephroptosis Nephrostomy tube Pelvic kidney

• • • • • • • • • • •

Polycystic kidney Prostatic hypertrophy Pyelonephritis Renal calculi Renal hypotension Staghorn calculus (see Fig. 6–110) Supernumerary kidney Uremia Ureteral stent Ureterocele Vesicoureteral re ux

Female Reproductive System Introduction. T e emale reproductive system consists o the ovaries, oviducts, and uterus. T e broad, suspensory, round, and ovarian ligaments are all associated with support o the reproductive organs.

202

A

PART II IMAGING PRO CEDURES

B

Figure 6–110. Although radiograph (A) may appear to be part of an IVU examination, no contrast agent is associated with the opaque right kidney; the opaque area is due to formation of a staghorn calculus. Radiograph (B) is a 1-hour IVU demonstrating both collecting systems. Staghorn calculi are usually associated with chronic infection and alkaline urine. They may be associated with a single calyx or an entire renal pelvis and may be unilateral or bilateral. Whenever possible, staghorn (named for their shape, resembling a stag’s antlers) calculi are removed because they can cause partial obstruction of the calyces and/or ureteropelvic junction. (From the American College of Radiology Learning File. Photo Contributor: ACR.)

T e ovaries are the emale gonads that unction to release ova ( emale reproductive cells) during ovulation and produce various emale hormones, including estrogen and progesterone. T e oviducts, or Fallopian tubes, are 3″ to 5″ long, arise rom the uterine cornua (angles), and extend laterally to arch over each ovary. T e oviduct lateral extremities are broader than their medial ends and are bordered by motile mbriae (see Figs. 6–111 and 6–112). T e mbriae sweep over the ovary and unction to collect the liberated ovum. Fertilization o the ovum usually occurs in the outer portion o the oviducts. Ova are propelled through the oviduct by peristaltic motion. Salpingitis is possibly the most common cause o emale sterility; i ertilization does occur, the zygote is unable to traverse the oviduct due to its scarred or narrowed condition. Occasionally, a ertilized ovum will become implanted in the oviduct, a condition known as ectopic, or tubal, pregnancy. T is condition is a gynecologic emergency because, i le untreated, the patient can die rom internal hemorrhage. T e most superior, arched, portion o the uterus is the undus. T e angle on each side is the cornu and marks the point o entry o the oviducts. T e body is the large central region and the narrow in erior portion is the cervix. Hysterosalpingogram. T e most commonly per ormed radiologic examination o the reproductive system is hysterosalpingography, which is

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

Corpus lute um

Ova ria n follicle s

Is thmus of ute rine tube Ova ria n liga me nt

Ampulla

Ute rine tube (Fa llopia n tube ) Ute rine cavity Fundus of ute rus

Endome trium Myome trium

Infundibulum Broa d liga me nt

Fimbria e

Inte rna l os

Ova ria n ve s s e ls

Ova ry Body of ute rus

Fornix

Ce rvica l ca na l Exte rna l os Ce rvix Va gina

Figure 6–111. Uterus, uterine tubes (oviducts), and ovaries.

employed or evaluation o the uterus, oviducts, and ovaries o the emale reproductive system. T e procedure serves to delineate the position, size, and shape o the structures and demonstrates pathology such as polyps, tumors, and stulas. However, it is most o en used to demonstrate patency o the oviducts in cases o in ertility and is sometimes therapeutic in terms o opening a blocked oviduct. Hysterosalpingograms should be scheduled approximately 10 days a er the start o menstruation. T is is the time just be ore ovulation, when there should be little chance o irradiating a newly ertilized ovum.

A

B

Figure 6–112. (A) AP projection of hysterosalpingogram study. Contrast- lled uterus and oviducts are shown, with spillage into pelvic cavity. (Photo Contributor: Stamford Hospital, Department of Radiology.) (B) Large mass distorting uterus.

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PART II IMAGING PRO CEDURES

TABLE6–54. Hysterosalpingogram HSG

Position o Part

AP

• •

Central Ray Directed

Supine, MSP centered to grid A point 2″ above the pubic symphysis centered to the IR

mid-IR

•

Structures Included/Best Seen • •

AP proj of uterus and oviducts 30º obliques may be made as required (see Fig. 6–112 A and B)

A er the cervical canal is cannulated, an iodinated contrast agent is injected via the cannula into the uterine cavity. I the oviducts are patent, contrast will ow through them and into the peritoneal cavity. Fluoroscopy is per ormed during injection and spot images are taken. Overhead radiographs may be per ormed ollowing the uoroscopic procedure. able 6–54 addresses positioning or hysterosalpingography. Terminology and Pathology. T e ollowing is a list o radiographically signi cant reproductive conditions with which the student radiographer should be amiliar:

Te le nce pha lon (ce re bra l he mis phe re )

• • • •

Bicornuate uterus Ectopic pregnancy Endometriosis In ertility

• • • •

Leiomyoma Pelvic in ammatory disease Placenta previa Salpingitis

Die nce pha lon

Central Nervous System

Midbra in Bra in s te m

Pons

Ce re be llum

Me dulla oblonga ta S pina l cord

Figure 6–113. The CNS: brain and spinal cord.

Introduction. T e central nervous system (CNS) is composed o the brain and spinal cord (Fig. 6–113), enclosed within the bony skull and vertebral column. T e brain consists o the cerebrum (largest part), cerebellum, pons varolii, and medulla oblongata. T e gray matter o the brain consists o neuron cell bodies; the white matter consists o tracts (pathways) o axons. In transverse section, the spinal cord is seen to have an H-shaped con guration o gray matter internally, surrounded by white matter (Fig. 6–114). T e brain and spinal cord work together in the perception o sensory stimuli, in integration and correlation o stimuli with memory, and in neural actions resulting in coordinated motor responses to stimuli. T e CNS is enclosed within three tissue membranes, the meninges. T e pia mater is the innermost vascular membrane, which is closely attached to the brain and spinal cord. T e arachnoid mater is a thin layer outside the pia mater and attached to it by web-like bers. T e subarachnoid space is between the pia and arachnoid mater and is lled with cerebrospinal uid (CSF). T e brain and spinal cord oat in CSF, which acts as a shock absorber. Cerebral artery hemorrhage will leak blood into the CSF. Lumbar puncture is per ormed (between L3 and L4 or L4 and L5) to remove small quantities o CSF or testing and to introduce contrast medium during myelography. T e dura mater is a double-layered brous membrane outside the arachnoid mater. T e subdural space is located between the arachnoid and dura mater; it does not contain CSF. T e epidural space is located between the two layers o dura mater.

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

T e cylindrical spinal cord is a continuation o the medulla oblongata, extending through the oramen magnum and spinal canal to its termination at the conus medullaris (about the level o L1). T e lumbar and sacral nerves have long roots that extend rom the spinal cord as the cauda equina (horse’s tail). Procedures. Routine radiographic examination o the bony components o the CNS includes studies o the skull and vertebral column. Computerized tomography (C ) and magnetic resonance imaging (MRI) procedures have replaced many plain radiographic procedures in the diagnosis and management o traumatic injuries and pathologic processes o the brain and spinal cord. Myelogram. Nevertheless, myelography remains a valuable diagnostic tool to demonstrate the site and extent o spinal cord tumors and herniated intervertebral disks. T e intervertebral disk can rupture due to trauma or degeneration. T e nucleus pulposus protrudes posteriorly through a tear in the annulus brosus and impinges on nerve roots (Fig. 6–115). More than 90% o disk ruptures occur at the L4–L5 and L5–S1 interspaces. Narrowing o the a ected disk space may o en be detected radiographically and the de ects caused by the rupture can generally be demonstrated through myelography, C , or MRI. Water-soluble nonionic iodinated contrast agents are the most widely used contrast media or myelography. Advantages o water-soluble contrast agents (over non–water-soluble) include better visualization o the nerve roots (see Fig. 6–116) and absorption properties that allow it to be le in the subarachnoid space a er the examination (because it is easily absorbed by the body). However, the use o water-soluble contrast agents or myelography does require that radiographs be made accurately and without delay, because it is absorbed airly quickly. Foot and shoulder supports must be securely attached to the x-ray table. T e patient should receive a complete explanation o the examination and must be instructed about the importance o keeping his or her chin extended when the table is lowered into the rendelenburg position. A lumbar puncture is per ormed (usually at the ourth intervertebral space with the patient in the prone or exed lateral position), a small quantity o CSF is removed rom the subarachnoid space and sent to the laboratory or testing, and an equal amount o contrast agent is injected intrathecally (i.e., into the subarachnoid space o the spinal canal). T e position o the contrast column will change according to gravitational orces, and its movement is observed uoroscopically as the x-ray table is angled to varying degrees o rendelenburg position and Fowler position. Fluoroscopic spot images are taken as needed, ollowed by overhead radiographs. Routine protocol generally includes an AP or PA and a horizontal beam (cross-table) lateral view o the vertebral area examined.

205

Dors a l column Dors a l gray column

Ce ntra l ca na l

La te ra l column

Ve ntra l white commis s ure

Ve ntra l gray column

Ve ntra l column

Figure 6–114. Cross section of the spinal cord.

Terminology and Pathology. T e ollowing is a list o radiographically signi cant CNS conditions with which the student radiographer should be amiliar: • • • •

Degenerative disk disease Herniated nucleus pulposus Hydrocephalus Meningioma

• • • •

Parkinson disease Meningitis Meningomyelocele Spondylosis

Figure 6–115. Myelograms demonstrating herniated L4–L5 disk. (Reproduced with permission from deGroot J. Correlative Neuroanatomy, 21st ed. East Norwalk, CT: Appleton &Lange, 1991.)

206

PART II IMAGING PRO CEDURES

A

B

Figure 6–116. (A) Oil-base contrast myelography. (Photo Contributor: Stamford Hospital, Department of Radiology.) (B) Water-soluble contrast myelography; observe improved visualization of nerve roots seen at the level of each pedicle as linear radiolucencies within the small inferolateral extensions of the contrast agent. (From the American College of Radiology Learning File. Photo Contributor: ACR.)

Circulatory System Introduction. T e circulatory system consists o the heart and vessels (arteries, capillaries, veins) that distribute blood throughout the body (see Fig. 6–117). T e heart is the muscular pump, and the arteries conduct oxygenated blood throughout the body. T e capillaries are responsible or di usion o gases and exchange o nutrients and wastes. T e veins collect deoxygenated blood and return it to the heart and lungs. Contraction o the heart muscle as it pumps blood is called systole; relaxation is called diastole; these values are measured with a sphygmomanometer. Accompanying the contraction and expansion o the heart is contraction and expansion o arterial walls, called pulse. T e heart wall is made up o the external epicardium, the middle myocardium, and the internal endocardium. T e pericardium is the broserous sac enclosing the heart and roots o the great vessels. T e heart has our chambers. T e two upper chambers are the atria and the two lower chambers are the ventricles. T e apex o the heart is the tip o the le ventricle. 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) vena cavae and the coronary sinus ( rom the heart substance; see Fig. 6–118). Upon atrial systole, the blood passes through the tricuspid valve into the

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

Right common ca rotid

Le ft common ca rotid Le ft s ubclavia n

Right s ubclavia n

De s ce nding a orta

Bra chioce pha lic Aortic a rch

Axilla ry

As ce nding a orta

Thora cic a orta

Ce lia c trunk

Abdomina l a orta

Bra chia l Re na l Gona da l Ra dia l S upe rior me s e nte ric

Ulna r

Infe rior me s e nte ric Common ilia c Inte rna l ilia c Exte rna l ilia c Pa lma r a na s tomos e s

De e p fe mora l Fe mora l

Poplite a l

Pe rone a l Pos te rior tibia l Ante rior tibia l

P la nta r a na s tomos e s

Dors a lis pe dis

Figure 6–117. The major arteries of the cardiovascular system.

right ventricle. During ventricular systole, the blood is pumped through the pulmonary semilunar valve into the pulmonary artery (the only artery to carry deoxygenated blood) to the lungs or oxygenation. Blood is returned via the pulmonary veins (the only veins to carry oxygenated blood) to the le atrium. During atrial systole, blood passes through the mitral (bicuspid) valve into the le ventricle. During

207

208

PART II IMAGING PRO CEDURES

10

1 Blood e nte rs right a trium from s upe rior a nd infe rior ve na e ca va e .

Aorta Le ft pulmona ry a rte ry

11 5

5 9

Pulmona ry trunk

S upe rior ve na cava Right pulmona ry ve ins

4

6

6

Le ft pulmona ry ve ins Le ft a trium

1

Aortic va lve 7

3 Right a trium

Le ft AV va lve

8 2

Right AV va lve

Le ft ve ntricle

3 Contra ction of right ve ntricle force s pulmona ry va lve ope n. 4 Blood flows through pulmona ry va lve into pulmona ry trunk. 5 Blood is dis tribute d by right a nd le ft pulmona ry a rte rie s to the lungs , whe re it unloa ds CO 2 a nd loa ds O 2 . 6 Blood re turns from lungs via pulmona ry ve ins to le ft a trium. 7 Blood in le ft a trium flows through le ft AV va lve into le ft ve ntricle . 8 Contra ction of le ft ve ntricle (s imulta ne ous with s te p 3 ) force s a ortic va lve ope n. 9 Blood flows through a ortic va lve into a s ce nding a orta .

Right ve ntricle Infe rior ve na cava

2 Blood in right a trium flows through right AV va lve into right ve ntricle .

10 Blood in a orta is dis tribute d to e ve ry orga n in the body, whe re it unloa ds O 2 a nd loa ds CO 2 .

11

11 Blood re turns to right a trium via ve na e ca va e .

Figure 6–118. Cardiopulmonary circulation. Blood ow is indicated by arrows and numbers: 1: Deoxygenated blood entering RA (1) from superior and inferior vena cava (11), 2: blood ows from RA (1) through right AV (tricuspid) valve (2) into RV, 3: RV contraction opens pulmonary semilunar valve (3) and blood ows into pulmonary artery (4), 4: blood enters lungs via right and left pulmonary arteries (5), releases CO2, and undergoes oxygenation, 5: newly oxygenated blood enters LA via 4 pulmonary veins (6), 6: blood ows from LA through left AV (mitral) valve (7) into LV (8), 7: LV (8) contraction opens aortic semilunar valve and blood ows into ascending aorta (9). Aorta and its branches (10) distribute oxygenated blood to all body tissues. CO2 is collected by the venous system and deoxygenated blood is returned via the superior and inferior vena cava (11) to the RA. (From Saladin K. Anatomy &Physiology: The Unity o Form and Function. 7th ed. New York, NY: McGraw-Hill Education; 2014.)

Pulmonary Circulation

•

Unoxygenated blood from the right side of the heart is directed to the lungs for oxygenation, then to the left side of the heart

Systemic Circulation

•

Oxygenated blood from the left side of the heart is pumped to the body tissues then back to the right side of the heart

ventricular systole, the oxygenated blood is pumped through the aortic semilunar valve into the aorta. When blood pressure is reported, as or example “130 over 85,” the top number (130) represents the systolic pressure and the lower number (85) represents the diastolic pressure. T e aorta is the trunk artery o the body; it is divided into the ascending aorta, aortic arch (see Fig. 6–119), descending thoracic aorta, and abdominal aorta. Many arteries arise rom the aorta to supply destinations throughout the body. T e superior and in erior vena cavae and the coronary sinus are the major veins, collecting venous blood rom the upper and lower body areas and heart substance, respectively. T e ormation o sclerotic plaques (as in atherosclerosis) and other conditions that impair the ow o blood can lead to ischemia and tissue in arction. Atherosclerosis o the coronary arteries can cause angina pectoris and myocardial in arction. T e our divisions o the aorta and their major branches are as ollows: Ascending Aorta

• L and R coronary arteries

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

Le ft common ca rotid a rte ry

Ophtha lmic a rte ry

Le ft s ubclavia n a rte ry

Bra chioce pha lic trunk

3 2 1

4

Four s e gme nts of thora cic a orta 1. Aortic bulb 2. As ce nding a orta 3. Aortic a rch 4. De s ce nding a orta

209

Ba s ila r a rte ry

Inte rna l ca rotid a rte ry Exte rna l ca rotid a rte ry Ve rte bra l a rte ry

Right common ca rotid a rte ry

Le ft s ubclavia n a rte ry

Innomina te a rte ry

Aorta A

B

Figure 6–119. (A) Thoracic aorta illustrating major branches of aortic arch. (B) Blood supply to the brain. (Reproduced with permission from Doherty GM, ed. Current Surgical Diagnosis &Treatment, 12th ed. New York: McGraw-Hill, 2006:824.)

Aortic Arch (Fig. 6–119A and B) • Brachiocephalic (Innominate) artery • R common carotid artery • R subclavian artery • L common carotid artery • L subclavian artery Blood Supply to the Brain • Internal carotid arteries (Fig. 6–119A and B) • Branch rom common carotid arteries • Supply anterior brain • Vertebral arteries • Branch rom subclavian arteries • Supply posterior brain T • • • •

oracic Aorta Intercostal arteries Superior phrenic arteries Bronchial arteries Esophageal arteries

Abdominal Aorta • In erior phrenic arteries

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• Celiac (axis) artery/trunk gives rise to: • Common hepatic artery • L Gastric artery • Splenic artery • Superior mesenteric artery • Suprarenal arteries • Renal arteries • Gonadal arteries (testicular or ovarian) • In erior mesenteric artery • Common Iliac arteries give rise to: • Internal iliac arteries • External iliac (Hypogastric) arteries Arteries of the Lower Limb • • • • • •

Internal iliac arteries External iliac arteries Femoral arteries Popliteal arteries Anterior tibial arteries and posterior tibial arteries Dorsalis pedis, peroneal/ bular, medial, and lateral plantar arteries

T e majority o peripheral and visceral angiographic procedures are per ormed in a specially equipped angiographic suite by cardiovascular– interventional technologists (Figs. 6–120 and 6–121). Many cardiovascular suites today use digital subtraction angiography (DSA). Subtraction

A

B

Figure 6–120. Lower limb arteriogram subtraction demonstrating aneurysm, be ore (A) and a ter (B) repair. (Photo Contributor: Stamford Hospital, Department of Radiology.)

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

211

Figure 6–121. The renal arteriogram is one of many types of procedures performed by specially trained teams of health care professionals. (From the American College of Radiology Learning File. Photo Contributor: ACR.)

is a technique that removes unnecessary structures such as bone rom superimposition on contrast- lled blood vessels. DSA is subtraction achieved by means o a computer, which can also permit manipulation o contrast and other image characteristics by the technologist. T e student radiographer, while not per orming most o these examinations, should be amiliar with the names o the most common procedures and the conditions and disorders or which they are per ormed. Venogram. T e one vascular procedure that might still be per ormed in general radiography is the lower limb venogram (Fig. 6–122). T is examination is generally per ormed to con rm a suspected deep vein thrombosis in an e ort to avoid the complications o a pulmonary embolism. T e patient should be examined on a radiographic table that can be tilted to a semierect position o at least 45°. ourniquets are used to orce contrast medium into the deep veins. Sterile technique must be rigorously maintained. An injection o 50 to 100 mL at 1 to 2 mL/second is usually made through a super cial vein in the oot. Images are made at approximately 5- to 10-second intervals o the lower leg, thigh, and pelvis. Terminology and Pathology. T e ollowing is a list o radiographically signi cant circulatory conditions with which the student radiographer should be amiliar: • • • • • • • •

Aneurysm Angina pectoris Atherosclerosis Atrial septal de ect CVA (cerebrovascular accident) Coarctation o aorta Congestive heart ailure Coronary artery disease

• • • • • • • •

Hypertension Myocardial in arction Phlebitis Pulmonary edema Pulmonary embolism Rheumatic heart disease T rombophlebitis Ventricular septal de ect

Figure 6–122. AP projection of a lower limb venogram demonstrating multiple intraluminal lling defects. (Reproduced with permission from Way LW, ed. Current Surgical Diagnosis & Treatment, 10th ed. East Norwalk, CT: Appleton &Lange, 1994.)

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PART II IMAGING PRO CEDURES

COMPREHENSION CHECK Congratulations! You have completed the last section of this chapter. If you are able to answer the following group of very comprehensive questions, you should feel con dent that you have really mastered this section. You can refer back to the indicated pages to check your answers and/or review the subject matter. 1. Identify the principal structures comprising the respiratory system and their function(s) (pp. 172–174). 2. Describe the (a) method of positioning, (b) direction and point of entry of the CR, (c) principal structures visualized, and (d) pertinent traumatic and pathologic conditions and any technical adjustments that may be required relative to the routine and special views of the chest (PA, lateral, obl, lordotic, decubitus) and airway (p. 171, 175). 3. Identify the principal structures comprising the biliary system and their function(s) (p. 178, 179). 4. Describe the (a) method of positioning, (b) direction and point of entry of the CR, (c) principal structures visualized, and (d) pertinent traumatic and pathologic conditions and any technical adjustments that may be required relative to the routine and special views of the biliary system, including A. Surgical cholangiography (p. 179). B. ERCP (p. 179).

7. Identify the principal structures comprising the urinary system and their function(s) (pp. 194–196). 8. Describe the (a) method of positioning, (b) direction and point of entry of the CR, (c) principal structures visualized, and (d) pertinent traumatic and pathologic conditions and any technical adjustments that may be required relative to the routine and special views of the urinary system, to include A. KUB (p. 199). B. Intravenous urography (p. 199, 200) C. Compression (p. 192, 194). D. Retrograde examinations (p. 199). E. Bladder (p. 200). F. Voiding examinations: male versus female (p. 199, 200). 9. Identify the principal structures comprising the female reproductive system and their function(s) (pp. 201–203). 10. Describe the (a) method of positioning, (b) direction and point of entry of the CR, (c) principal structures visualized, and (d) pertinent traumatic and pathologic conditions and any technical adjustments that may be required in hysterosalpingography (p. 203, 204).

5. Identify the principal structures comprising the digestive system and their function(s) (pp. 181–185).

11. Identify the principal structures comprising the CNS and their function(s) (p. 204, 205).

6. Describe the (a) method of positioning, (b) direction and point of entry of the CR, (c) principal structures visualized, and (d) pertinent traumatic and pathologic conditions and any technical adjustments that may be required relative to the routine and special views of the digestive system, to include

12. Describe the (a) indications for (b) principal structures visualized, and (c) pertinent traumatic and pathologic conditions and any technical adjustments that may be required in myelography (p. 205).

A. Swallowing dysfunction/deglutition study (p. 180)

14. List the kinds of specialized examinations that might be performed to demonstrate various traumatic and pathologic conditions of the circulatory system (p. 209, 210).

B. Abdomen (p. 186). C. Esophagus (p. 189). D. Stomach and small intestine (p. 190). E. Large intestine (p. 192).

13. Identify the principal structures comprising the circulatory system and their function(s) (pp. 206–209).

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

CHAPTER REVIEW QUESTIONS Congratulations! You have completed this chapter. You may go on to the “Registry-type” multiple-choice questions that follow. For greatest success, be sure to also complete the short-answer questions found at the end of each section of this chapter. Questions 1 through 10 refer to the Appendicular Skeleton section 1. In the AP projection of the knee, the 1. Patella is visualized through the femur 2. CR is directed ½″ distal to the patellar base 3. CR is directed 3 to 5° cephalad when the distance between the tabletop and ASIS is 17 cm (A) 1 only (B) 1 and 2 only (C) 2 and 3 only (D) 1, 2, and 3 2. A Colles fracture usually involves the following: 1. Transverse fracture of the distal radius 2. Posterior and outward displacement of the hand 3. Chip fracture of the ulnar styloid process (A) 1 only

4. In the 15–20° mortise oblique position of the ankle, the 1. Talo bular joint is visualized 2. Talotibial joint is visualized 3. Plantar surface should be vertical (A) 1 only (B) 1 and 3 only (C) 2 and 3 only (D) 1, 2, and 3 5. The following projection(s) should not be performed until a transverse fracture of the patella has been ruled out: 1. AP knee 2. Lateral knee 3. Axial/tangential patella (A) 1 only (B) 1 and 2 only (C) 2 and 3 only (D) 1, 2, and 3 6. Which of the following best demonstrates the cuboid, sinus tarsi, and tuberosity of the fth metatarsal?

(B) 1 and 2 only

(A) Lateral foot

(C) 2 and 3 only

(B) Lateral oblique foot

(D) 1, 2, and 3

(C) Medial oblique foot

3. Which of the following projections require(s) that the humeral epicondyles be superimposed? 1. Lateral thumb

(D) Weight-bearing foot 7. The left sacroiliac joint is placed perpendicular to the IR when the patient is placed in a

2. Lateral wrist

(A) Left lateral position

3. Lateral humerus

(B) 25–30º RAO position

(A) 1 only

(C) 25–30º RPO position

(B) 1 and 2 only

(D) 30–40º RPO position

(C) 2 and 3 only (D) 1, 2, and 3

8. The proximal tibio bular articulation is best demonstrated in which of the following positions? (A) Medial oblique (B) Lateral oblique (C) AP (D) Lateral

213

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PART II IMAGING PRO CEDURES

9. An axial projection of the clavicle is often helpful in demonstrating a fracture not visualized using a perpendicular central ray. When examining the clavicle in the AP axial projection, how should the central ray be directed? (A) Cephalad (B) Caudad (C) Medially (D) Laterally 10. The scapular Yprojection of the shoulder demonstrates 1. A lateral projection of the shoulder 2. Anterior or posterior dislocation 3. An oblique projection of the shoulder (A) 1 only (B) 1 and 2 only (C) 2 and 3 only (D) 1, 2, and 3 Questions 11 through 20 refer to the Axial Skeleton section 11. In the AP axial projection (Towne method) of the skull, with the central ray directed 30º caudad to the OML and passing midway between the external auditory meati, which of the following is best demonstrated?

13. The AP projection of the coccyx requires that the central ray be directed 1. 15º cephalad 2. 2″ above the pubic symphysis 3. Midline at the level of the lesser trochanter (A) 1 only (B) 2 only (C) 1 and 2 only (D) 1 and 3 only 14. Which of the following is (are) demonstrated in the oblique projection of the thoracic spine? 1. Intervertebral joints 2. Zygapophyseal joints 3. Intervertebral foramina (A) 1 only (B) 2 only (C) 1 and 2 only (D) 1 and 3 only 15. The thoracic vertebrae are unique in that they participate in the following articulations: 1. Costovertebral 2. Costotransverse 3. Costochondral (A) 1 only

(A) Facial bones

(B) 1 and 2 only

(B) Frontal bone

(C) 2 and 3 only

(C) Occipital bone

(D) 1, 2, and 3

(D) Basal foramina 12. Which of the following is a functional study used to demonstrate the degree of AP motion present in the cervical spine?

16. In order to demonstrate undistorted air/ uid levels, the CR must always be directed (A) Parallel with the long axis of the body/part (B) Parallel with the oor

(A) Open-mouth projection

(C) Perpendicular to the long axis of the body/part

(B) Moving mandible AP

(D) Perpendicular to the oor

(C) Flexion and extension laterals (D) Right and left bending

17. All of the following statements regarding the PA projection of the skull, with central ray perpendicular to the IR are true, except (A) Orbitomeatal line is perpendicular to the IR (B) Petrous pyramids ll the orbits (C) Midsagittal plane (MSP) is parallel to the IR (D) Central ray exits at the nasion

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

18. Which of the paranasal sinuses is composed of many thin-walled air cells?

23. Chest radiography should be performed using 72″ SID whenever possible in order to

(A) Frontal

1. Visualize vascular markings

(B) Sphenoid

2. Obtain better lung detail

(C) Ethmoid

3. Maximize magni cation of the heart

(D) Maxillary

(A) 1 only

19. The intervertebral joints of the thoracic spine are demonstrated with the (A) Midcoronal plane 45º to the IR (B) Midsagittal plane 45º to the IR (C) Midcoronal plane 70º to the IR (D) Midsagittal plane parallel to the IR 20. Which of the following structures is subject to blowout fracture? (A) Ethmoid sinuses (B) Zygomatic arch (C) Mandibular condyle (D) Orbital oor Questions 21 through 60 refer to the Body Systems section 21. Aspirated foreign bodies in older children and adults are most likely to lodge in the (A) Right main bronchus

(B) 1 and 2 only (C) 2 and 3 only (D) 1, 2, and 3 24. Blunting of the costophrenic angles seen on a PA projection of the chest can be an indication of (A) Pleural e usion (B) Ascites (C) Bronchitis (D) Emphysema 25. Which of the following conditions is characterized by “ attening”of the diaphragm? (A) Emphysema (B) Empyema (C) Atelectasis (D) Pneumonia 26. Inspiration and expiration projections of the chest may be performed to demonstrate

(B) Left main bronchus

1. Pneumothorax

(C) Esophagus

2. Presence of foreign body

(D) Proximal stomach

3. Bronchitis

22. Which of the following is (are) important when positioning the patient for a PA projection of the chest?

(A) 1 only (B) 1 and 2 only

1. The patient should be examined erect.

(C) 1 and 3 only

2. Clavicles should be brought above the apices.

(D) 1, 2, and 3

3. Scapulae should be brought lateral to the lung elds.

27. Which of the following criteria are used to evaluate a good PA projection of the chest?

(A) 1 only

1. Ten posterior ribs should be visualized.

(B) 1 and 2 only

2. Sternoclavicular joints should be symmetrical.

(C) 1 and 3 only

3. Scapulae should be outside the lung elds.

(D) 1, 2, and 3

(A) 1 and 2 only (B) 1 and 3 only (C) 2 and 3 only (D) 1, 2, and 3

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28. All of the following statements regarding respiratory structures are true, except (A) The right lung has three lobes.

33. Which of the following projections of the abdomen could be used to demonstrate air or uid levels when the erect position cannot be obtained?

(B) The uppermost portion of a lung is its apex.

1. AP Trendelenburg

(C) The lobes of the left lung are separated by the horizontal ssure.

2. Dorsal decubitus

(D) The trachea bifurcates into mainstem bronchi.

(A) 1 only

29. To demonstrate the pulmonary apices below the level of the clavicles in the AP position, the CR should be directed (A) Perpendicular (B) 15 to 20º caudad

3. Lateral decubitus (B) 1 and 2 only (C) 2 and 3 only (D) 1, 2, and 3 34. Which of the following best describes the relationship between the esophagus and trachea?

(C) 15 to 20º cephalad

(A) Esophagus is posterior to the trachea.

(D) 40º cephalad

(B) Trachea is posterior to the esophagus.

30. Radiographic indications of atelectasis include(s)

(C) Esophagus is lateral to the trachea.

1. Decreased radiographic density/increased brightness of the a ected side

(D) Trachea is lateral to the esophagus.

2. Elevation of the hemidiaphragm of the a ected side 3. Flattening of the hemidiaphragm of the a ected side (A) 1 only (B) 3 only (C) 1 and 2 only (D) 1 and 3 only 31. During IV urography, the prone position is generally recommended to demonstrate 1. Filling of obstructed ureters 2. The renal pelvis 3. The superior calyces (A) 1 only (B) 1 and 2 only (C) 1 and 3 only (D) 1, 2, and 3 32. The contraction and expansion of arterial walls in accordance with forceful contraction and relaxation of the heart is called (A) Hypertension (B) Elasticity (C) Pulse (D) Pressure

35. To demonstrate esophageal varices, the patient must be examined in the (A) Recumbent position (B) Erect position (C) Anatomic position (D) Fowler position 36. The usual preparation for an upper GI series is (A) Clear uids 8 hours prior to examination (B) NPO after midnight (C) Enemas until clear before examination (D) Light breakfast day of the examination 37. Which of the following positions would best demonstrate a double contrast of the left and right colic exures? (A) Left lateral decubitus (B) AP recumbent (C) Right lateral decubitus (D) AP erect 38. In which of the following positions are a barium- lled pyloric canal and duodenal bulb best demonstrated during a GI series? (A) RAO (B) Left lateral (C) Recumbent PA (D) Recumbent AP

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

39. What position is frequently used to project the GB away from the vertebrae in the asthenic patient? (A) RAO

44. During a gastrointestinal examination, the AP recumbent projection of a stomach of average size and shape will usually demonstrate

(B) LAO

1. Barium- lled fundus

(C) Left lateral decubitus

2. Double contrast of distal stomach portions

(D) PA erect

3. Barium- lled duodenum and pylorus

40. Which of the following barium/air- lled anatomic structures is best demonstrated in the RAO position? (A) Splenic exure (B) Hepatic exure (C) Sigmoid colon (D) Ileocecal valve 41. In what order should the following studies be performed?

(A) 1 only (B) 1 and 2 only (C) 1 and 3 only (D) 1, 2, and 3 45. Which of the following examinations require(s) catheterization of the ureters? 1. Retrograde urogram 2. Cystogram 3. Voiding cystogram

1. Barium enema

(A) 1 only

2. Intravenous urogram

(B) 1 and 2 only

3. Upper GI

(C) 2 and 3 only

(A) 3, 1, 2

(D) 1, 2, and 3

(B) 1, 3, 2 (C) 2, 1, 3 (D) 2, 3, 1 42. All of the following statements regarding the urinary system are true, except

46. Some common mild side e ects of intravenous administration of water-soluble iodinated contrast agents include 1. Flushed feeling 2. Bitter taste

(A) The left kidney is usually higher than the right.

3. Urticaria

(B) The kidneys move inferiorly in the erect position.

(A) 1 only

(C) The upper, expanded part of the ureter is the hilum.

(B) 1 and 2 only

(D) Vessels, nerves, and lymphatics pass through the renal hilum.

(D) 1, 2, and 3

43. Which of the following examinations require(s) restriction of the patient’s diet? 1. GI series 2. Abdominal survey 3. Urogram (A) 1 only (B) 1 and 2 only (C) 1 and 3 only (D) 1, 2, and 3

(C) 1 and 3 only 47. Hysterosalpingograms may be performed for the following reason(s): 1. Demonstration of stulous tracts 2. Investigation of infertility 3. Demonstration of tubal patency (A) 1 only (B) 1 and 2 only (C) 1 and 3 only (D) 1, 2, and 3

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PART II IMAGING PRO CEDURES

48. A postvoid image of the urinary bladder is usually requested at the completion of an IVU and may be helpful in demonstrating

53. The method by which contrast- lled vascular images are removed from superimposition upon bone is called

1. Residual urine

(A) Positive masking

2. Prostate enlargement

(B) Reversal

3. Ureteral tortuosity

(C) Subtraction

(A) 1 only

(D) Registration

(B) 1 and 2 only (C) 1 and 3 only (D) 1, 2, and 3 49. During routine intravenous urography, the oblique position demonstrates the (A) Kidney of the side up parallel to the IR (B) Kidney of the side up perpendicular to the IR (C) Urinary bladder parallel to the IR (D) Urinary bladder perpendicular to the IR 50. To better demonstrate contrast- lled distal ureters during intravenous urography, it is helpful to

54. Indicate the correct sequence of oxygenated blood as it returns from the lungs to the heart (A) Pulmonary veins, left atrium, left ventricle, aortic valve (B) Pulmonary artery, left atrium, left ventricle, aortic valve (C) Pulmonary veins, right atrium, right ventricle, pulmonary semilunar valve (D) Pulmonary artery, right atrium, right ventricle, pulmonary semilunar valve 55. In myelography, the contrast medium is generally injected into the

1. Use a 15º AP Trendelenburg position

(A) Cisterna magna

2. Apply compression to the proximal ureters

(B) Individual intervertebral disks

3. Apply compression to the distal ureters

(C) Subarachnoid space between the rst and second lumbar vertebrae

(A) 1 only (B) 2 only (C) 1 and 2 only (D) 1 and 3 only 51. The space located between the arachnoid mater and dura mater is the

(D) Subarachnoid space between the third and fourth lumbar vertebrae 56. The upper chambers of the heart are the (A) Ventricles (B) Atria

(A) Subarachnoid space

(C) Pericardia

(B) Subdural space

(D) Myocardia

(C) Epidural space (D) Epiarachnoid space

57. Myelography is a diagnostic examination used to demonstrate

52. During a GI examination, the lateral recumbent projection of a stomach of average shape will demonstrate

1. Posterior protrusion of herniated intervertebral disk

1. Anterior and posterior aspects of the stomach

2. Anterior protrusion of herniated intervertebral disk

2. Medial and lateral aspects of the stomach 3. Double-contrast body and antral portions (A) 1 only (B) 1 and 2 only (C) 2 and 3 only (D) 1, 2, and 3

3. Internal disk lesions (A) 1 only (B) 2 only (C) 1 and 2 only (D) 1 and 3 only

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

58. The four major arteries supplying the brain include the

60. The apex of the heart is formed by the (A) Left atrium

1. Brachiocephalic artery

(B) Right atrium

2. Common carotid arteries

(C) Left ventricle

3. Vertebral arteries

(D) Right ventricle

(A) 1 and 2 only (B) 1 and 3 only (C) 2 and 3 only (D) 1, 2, and 3 59. Venous, or deoxygenated, blood is returned to the heart via the 1. Inferior vena cava 2. Superior vena cava 3. Coronary sinus (A) 1 only (B) 2 only (C) 1 and 2 only (D) 1, 2, and 3

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PART II IMAGING PRO CEDURES

Answers and Explanations 1. (A) The AP projection of the knee requires the knee to be extended. There should be no pelvic rotation although the leg may be rotated 3 to 5° internally. The central ray is directed to 1/2″ below patellar apex (location of knee joint). The direction of the CR depends on the distance between the ASIS and the tabletop; that is, up to 19 cm (thin pelvis) angle 3 to 5º caudad; 19 to 24 cm is 0º (perpendicular) CR; greater than 24 cm (thick pelvis) 3 to 5º cephalad. This projection demonstrates an AP of the knee joint, distal femur, and proximal tibia/ bula. The patella is seen through the femur. The femoral condyles are superimposed in the lateral projection of the knee.

transverse fracture may be seen through the femur on the AP projection. The axial (sunrise) projection of the patella is generally used for demonstrating vertical patellar fractures.

2. (D) A Colles fracture is often caused by a fall onto an outstretched hand, in order to “brake” the fall. As a result, the wrist su ers an impacted transverse fracture of the distal inch of the radius, with displacement of the hand posteriorly (i.e., backward, approximately 30°) and outward, causing the characteristic “dinnerfork” deformity seen on x-ray examination. This injury is usually accompanied by a chip fracture of the ulnar styloid process.

7. (C) Sacroiliac joints lie obliquely in the pelvis and open anteriorly at an angle of 25 to 30° to the MSP. A 25º to 30º oblique position places the joints perpendicular to the IR. The left sacroiliac joint is demonstrated in the RPO and LAO positions with little di erence in magni cation.

3. (C) For the lateral projections of the hand, wrist, forearm, and elbow, the elbow must be exed 90° to superimpose the distal radius and ulna and humeral epicondyles. Although a lateral humerus can be performed with the elbow exed, if exion is not possible, the elbow may remain in the anteroposterior (AP) position and a transthoracic lateral projection of the upper one-half to twothirds of the humerus may be obtained. Because a coronal plane passing through the epicondyles (interepicondylar line) is perpendicular to the IR in this position, the epicondyles will be superimposed. To obtain a lateral projection of the thumb ( rst digit), the patient’s wrist must be somewhat internally rotated. Remember that an oblique projection of the thumb is obtained in a PA projection of the hand. 4. (D) The medial oblique projection (15–20° mortise view) of the ankle is valuable because it demonstrates the tibio bular joint as well as the talotibial joint, thereby visualizing all the major articulating surfaces of the ankle joint. To demonstrate maximum joint volume, it is recommended that the plantar surface be vertical. 5. (C) If a transverse fracture of the patella is present and the knee is exed, there is a danger of separation of the fractured segments. Because both a lateral knee and axial patella require knee exion, they should be avoided until a transverse fracture is ruled out. When present, a

6. (C) To demonstrate many of the tarsals and intertarsal spaces, including the cuboid, third (lateral) cuneiform, sinus tarsi, and tuberosity of the fth metatarsal, a medial oblique is required (plantar surface and IR form a 30º angle). The lateral oblique projection of the foot demonstrates the navicular and rst (medial) and second (intermediate) cuneiforms. Weight-bearing lateral feet are used to demonstrate the longitudinal arches.

8. (A) With the femoral condyles of the a ected side rotated medially/internally to form a 45º angle with the IR, the proximal tibio bular articulation is placed parallel with the IR and the bula is free of superimposition with the tibia. The lateral oblique completely superimposes the tibia and bula. The AP and lateral projections superimpose enough of the tibia and bula so that the tibio bular articulation is “closed.” 9. (A) With the patient positioned for an AP axial projection, the central ray is directed cephalad. The reverse is true when examining the clavicle in the prone position. This serves to project the pulmonary apices away from the clavicle. Patients having clavicular pain are more comfortably examined using the PA erect or AP recumbent projections/positions. 10. (C) The scapular Yprojection requires that the coronal plane be approximately 60° to the IR, thus resulting in an oblique projection of the shoulder. The vertebral and axillary borders of the scapula are superimposed on the humeral shaft and the resulting relationship between the glenoid fossa and humeral head will demonstrate anterior or posterior dislocation. Lateral or medial dislocation is evaluated on the AP projection. 11. (C) The AP axial projection is obtained by angling the central ray 30° caudad to the OML (Fig. 6–63A). This projects the anterior structures (frontal and facial bones) downward, thus permitting visualization of the occipital bone without superimposition (Towne method). The dorsum

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

sella and posterior clinoid processes of the sphenoid bone should be visualized within the foramen magnum. The rontal bone is best shown in the PA projection with a perpendicular central ray. The parietoacanthial projection is the single best position for acial bones. Basal oramina are well demonstrated in the submentovertical projection. 12. (C) The degree of anterior to posterior motion is occasionally diminished with a “whiplash”-type injury. Anterior (forward, exion) and posterior (backward, extension) motion is evaluated in the lateral position with the patient assuming exion and extension positions as much as possible. Left and right bending images of the vertebral column are frequently obtained to evaluate scoliosis. 13. (B) The AP projection of the coccyx requires that the CR be directed 10º caudally and centered to a point 2″ above the pubic symphysis. The AP projection of the sacrum requires a 15º cephalad angle of the CR, centered to a point midway between the pubic symphysis and the ASIS. 14. (B) Intervertebral joints are well visualized in the lateral projection of all the vertebral groups. Thoracic and lumbar intervertebral foramina are well demonstrated in the lateral projection. Thoracic and lumbar zygapophyseal joints are demonstrated in an oblique position—thoracic requires a 70° oblique and lumbar requires a 45° oblique. Cervical articular facets (forming zygapophyseal joints) are 90° to the midsagittal plane (MSP) and are therefore well demonstrated in the lateral projection. The cervical intervertebral foramina lie 45° to the MSP (and 15–20° to a transverse plane) and are therefore demonstrated in the oblique position. 15. (B) There are 12 thoracic vertebrae, which are larger in size than cervical vertebrae and which increase in size as they progress inferiorly toward the lumbar region. Thoracic spinous processes are fairly long and are sharply angled caudally. The bodies and transverse processes have articular acets for the diarthrotic rib articulations (seeFig. 6–48). These structures form the costovertebral (head of rib with body of vertebra) and costotransverse (tubercle of rib with transverse process of vertebra) articulations. The costochondral articulation describes where the anterior end of the rib articulates with its costal cartilage. 16. (B) Radiography of the paranasal sinuses, and other structures such as the chest, must be performed in the erect position so that any air/ uid levels may be demonstrated. In the paranasal sinuses, the erect position helps distinguish between uid and other pathology such as polyps. To demonstrate air/ uid levels, the CR must always be directed parallel to the oor, even if the patient is not

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completely erect (just as in chest radiography). If the CR is angled to parallel the plane of the body, any uid levels will be distorted or indeed obliterated. 17. (C) In the exact PA projection of the skull, the CR is perpendicular and exits the nasion. The petrous pyramids should ll the orbits. If the CR is angled caudally, the petrous pyramids are projected lower in the orbits; at approximately 25 to 30º caudal angle, they are projected below the orbits. In the PA projection, the OML must be perpendicular to the image receptor, or the petrous pyramids will not ll the orbits. The MSP must be perpendicular to the IR or the skull will be rotated and anatomic details will lose L–R symmetry. The MSP is parallel to the IR in the lateral projection of the skull. 18. (C) There are four paired paranasal sinuses: rontal, ethmoidal, maxillary, and sphenoidal (see Fig. 6–69). They vary greatly in their size and shape. The left and right rontal sinuses are usually asymmetrical. They are located behind the glabella and super-ciliary arches of the frontal bone. The rontal sinuses are not present in young children and generally reach their adult size in the 15th or 16th year. The ethmoid sinuses are composed of 6 to 18 thin-walled air cells that occupy the bony labyrinth of the ethmoid bone. The ethmoidal sinuses of children are very small and do not fully develop until after the 14th year. The maxillary sinuses (maxillary antra/antra of Highmore) are the largest of the paranasal sinuses and are located in the body of the maxillae. The maxillary antra are particularly prone to infection and collections of stagnant mucus. The maxillary antra reach their adult size around the 12th year. The sphenoid sinuses are located in the body of the sphenoid bone and are usually asymmetrical. They generally reach adult size by the 14th year. 19. (D) Intervertebral joints are well visualized in the lateral projection of all the vertebral groups. Thoracic and lumbar intervertebral oramina are well demonstrated in the lateral projection. Thoracic and lumbar zygapophyseal joints are demonstrated in an oblique position—thoracic requires a 70° oblique and lumbar requires a 45° oblique. Cervical articular facets (forming zygapophyseal joints) are 90° to the midsagittal plane (MSP) and are therefore well demonstrated in the lateral projection. The cervical intervertebral foramina lie 45° to the MSP (and 15–20° to a transverse plane) and are therefore demonstrated in the oblique position. 20. (D) The orbital cavities are formed by seven bones (frontal, sphenoid, ethmoid, maxilla, palatine, zygoma/

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malar, and lacrimal). The orbital walls are fragile and the orbital oor is subject to traumatic blowout fractures—the second most common facial fracture (nasal fractures being number one). Orbital fractures can be accompanied by injury to adjacent structures—bone, muscle, and other soft tissues. Leakage of air from the adjacent maxillary sinuses can cause orbital edema. Orbital oor fractures can be demonstrated using the parietoacanthial (Waters) projection; CT is often indicated for further evaluation. 21. (A) Because the right main bronchus is wider and more vertical, aspirated foreign bodies are more likely to enter it than the left main bronchus, which is narrower and angles more sharply from the trachea. An aspirated foreign body does not enter the esophagus or stomach, as they are digestive, not respiratory, structures. 22. (C) The chest should be examined in the erect position whenever possible to demonstrate any air or uid levels. The shoulders should be relaxed and depressed to move the clavicles below the lung apices. The shoulders should be rolled forward to move the scapulae out of the lung elds. 23. (B) Chest radiographs are performed in the erect position at 72″ SID whenever possible. The long sourceto-image receptor distance (SID) is easily achieved with a minimum patient exposure due to the low tissue densities being examined (ribs and lungs). The longer SID minimizes magni cation of the heart and provides better visualization of pulmonary vascular markings. 24. (A) Fluid in the thoracic cavity between the visceral and parietal pleura is called pleural e usion. In the erect position, fluid gravitates to the lowest point, settling in, and “blunting,” the costophrenic angles. Ascites is an accumulation of serous fluid in the peritoneal cavity. Bronchitis is an inflammation of the bronchial tubes. Pulmonary emphysema is a chronic pulmonary disease characterized by increase beyond the normal in the size of air spaces distal to the terminal bronchiole and with destructive changes in the walls of the bronchioles. 25. (A) Emphysema is characterized by irreversible trapping of air, which gradually increases and overexpands the lungs, thus producing the characteristic attening o the diaphragm and widening o the intercostal spaces (see Fig. 6–81). The increased air content of the lungs requires a compensating decrease in technical actors. Empyema describes pus in the pleural cavity as a result of an infection of the lungs. Atelectasis is a collapsed or airless lung.

Pneumonia is an in ammation of the lung; there are more than 50 causes of pneumonia. 26. (B) Phase of respiration is exceedingly important in thoracic radiography; lung expansion and the position of the diaphragm strongly in uence the appearance of the nished radiograph. Inspiration and expiration radiographs of the chest are taken to demonstrate air in the pleural cavity (pneumothorax), to demonstrate degree of diaphragm excursion, or to detect the presence of foreign body. The expiration image will require a somewhat greater exposure (equivalent of 6–8 kVor more) to compensate for the diminished quantity of air in the lungs. 27. (D) To evaluate su cient inspiration and lung expansion, 10 posterior ribs should be visualized. Sternoclavicular joints should be symmetrical; any loss of symmetry indicates rotation. Accurate positioning and selection of technical factors is critical to the diagnostic value of the radiographic images. Even slight rotation or leaning can cause signi cant distortion of the heart size and shape. To visualize maximum lung area, the shoulders are rolled forward to remove the scapulae from the lung elds. 28. (C) The trachea (windpipe) bifurcates into left and right mainstem bronchi, each entering its respective lung hilum. The left bronchus divides into two parts, one for each lobe of the left lung; the right bronchus divides into three parts, one for each lobe of the right lung. The lungs have a somewhat conical shape; their narrow upper portion is called the apex, and their wide lower portion is the base. Structures such as the main-stem bronchi and pulmonary artery and veins enter and leave the lungs at the hilum. The right lung has three lobes; the upper and middle lobes are separated by the horizontal ssure, and the middle and lower lobes are separated by the oblique ssure. The le t lung has two lobes; the upper and lower lobes are separated by the oblique ssure (see Fig. 6–76). 29. (C) When the shoulders are relaxed, the clavicles are usually carried below the pulmonary apices. To examine the portions of lungs lying behind the clavicles, the CR is directed 15 to 20° cephalad to project the clavicles above the apices, when the patient is examined in the AP position. 30. (C) Pneumothorax is the presence of air in the pleural cavity. A large pneumothorax is usually accompanied by a partial or complete atelectasis (collapse of the lung). Radiographic indications of atelectasis include an increase in tissue density of the collapsed lung (therefore,

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

decreased image density/increased brightness), and elevation of the hemidiaphragm of the af ected side. The procedure required to remove signi cant amounts of air, blood, or other uids in the pleural cavity is thoracentesis. 31. (B) The kidneys lie obliquely in the posterior portion of the trunk, with their superior portions angled posteriorly and their inferior portions and ureters angled anteriorly. Therefore, to facilitate lling of the most anteriorly placed structures, the patient is examined in the prone position. Opaci ed urine then ows to the most dependent part of the kidney and ureter—the ureteropelvic region, inferior calyces, and ureters. 32. (C) As the heart contracts and relaxes while functioning to pump blood from the heart, those arteries that are large and those in closest proximity to the heart will feel the e ect of the heart’s forceful contractions in their walls. The arterial walls pulsate in unison with the heart’s contractions. This movement may be detected with the ngers in various parts of the body and is referred to as the pulse. 33. (C) Air or uid levels will be clearly demonstrated only if the central ray is directed parallel to them. Therefore, to demonstrate air or uid levels, erect or decubitus positions should be used. A “three-way abdomen” study is often performed to evaluate possible obstruction or free air or uid within the abdomen and usually consists of anteroposterior (AP) recumbent, AP erect, and left lateral decubitus projections of the abdomen. 34. (A) The trachea (windpipe) is a tube-like passageway for air that is supported by C-shaped cartilaginous rings. The trachea is part of the respiratory system and is continuous with the main stem bronchi. The esophagus, part of the alimentary canal, is a hollow tube-like structure connecting the mouth and stomach, and lies posterior to the trachea. If one inadvertently aspirates food or drink into the trachea, choking occurs. 35. (A) Esophageal varices are tortuous dilatations of the esophageal veins. They are much less pronounced in the erect position and must always be examined with the patient recumbent. The recumbent position a ords more complete lling of the veins, as blood ows against gravity. 36. (B) The upper gastrointestinal (GI) tract must be empty for best x-ray evaluation. Any food or liquid mixed with the barium sulfate suspension can simulate pathology. Preparation therefore is to withhold food and uids for 8 to 9 hours before the examination, typically after

223

midnight, as fasting examinations are usually performed rst thing in the morning. 37. (D) To demonstrate structures via double contrast, the barium must be moved away from the area and replaced with air. The anteroposterior (AP) erect position will accomplish that for both the colic exures. The erect position allows barium to move downward, while air rises to ll the exures. The decubitus positions are useful to demonstrate the lateral and medial walls of the ascending and descending colon. 38. (A) The right anterior oblique (RAO) position a ords a good view of the pyloric canal and duodenal bulb. It is also a good position for the barium- lled esophagus, projecting it between the vertebrae and heart. The left lateral projection of the stomach demonstrates the left retrogastric space; the recumbent posteroanterior (PA) is used as a general survey of the gastric surfaces, and the recumbent anteroposterior (AP) with a slight left oblique a ords a double contrast of the pylorus and duodenum. 39. (B) There are four types of body habitus. Listed from largest to smallest, they are hypersthenic, sthenic, hyposthenic, and asthenic. The position, shape, and motility of various organs can di er greatly from one body type to another. The typical asthenic gallbladder (GB) is situated low and medial, often very close to the midline. To move the GB away from the midline, left anterior oblique (LAO) position is used. The GB of hypersthenic individuals occupies a high lateral and transverse position. 40. (B) In the prone oblique positions (right/left anterior oblique [RAO/LAO]), the exure disclosed is the one closer to the IR. Therefore, the RAO position will open up the hepatic exure. The anteroposterior (AP) oblique positions (right/left posterior oblique [RPO/LPO]) demonstrate the side away from the IR. 41. (C) When scheduling patient examinations, it is important to avoid the possibility of residual contrast medium covering areas of interest on later examinations. The intravenous urogram (IVU) should be scheduled rst because the contrast medium used is excreted rapidly. The barium enema (BE) should be scheduled next. The gastrointestinal (GI) series is scheduled last. Any barium remaining from the previous BE should not be enough to interfere with the stomach or duodenum, although a preliminary scout image should be taken in each case. 42. (C) The major components of the urinary system are the kidneys, ureters, and bladder. The tiny functional units within the renal substance are nephrons.

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The kidneys are retroperitoneal structures held in position by adipose tissue. They are located between the vertebral levels of T12 and L3. The right kidney is usually 1 to 2″ lower than the left because of the presence of the liver on the right. The kidneys move inferiorly 1″ to 3″ when the body assumes an erect position; they move inferiorly and superiorly during respiration. The slit-like opening on the medial concave surface of each kidney is the hilum, which opens into a space called the renal sinus (see Fig. 6–102). The renal artery and vein, lymphatic vessels, and nerves pass through the hilum. The upper, expanded portion of the ureter is called the renal pelvis, or in undibulum, and also passes through the hilum; it is continuous with the major and minor calyces within the kidney. 43. (C) A patient having a gastrointestinal (GI) series is required to be NPO (nothing by mouth) for at least 8 hours prior to the examination; food or drink in the stomach can simulate disease. A patient scheduled for a urogram must have the preceding meal withheld so as to avoid the possibility of aspirating vomitus in case of allergic reaction. An abdominal survey does not require the use of contrast medium and no patient preparation is required. 44. (B) With the body in the anteroposterior (AP) recumbent position, barium ows easily into the fundus of the stomach, displacing it somewhat superiorly. The fundus, then, is lled with barium, while the air that had been in the fundus is displaced into the gastric body, pylorus, and duodenum, illustrating them in double-contrast fashion. Air-contrast delineation of these structures allows us to see through the stomach to retrogastric areas and structures. Barium- lled duodenum and pylorus is best demonstrated in the right anterior oblique (RAO) position. 45. (A) Retrograde urograms require catheterization of the urethra and/or ureter(s). Radiographs that include the kidney(s) and ureter(s) in their entirety are made after retrograde lling of the structures. A cystogram or (voiding) cystourethrogram requires urethral catheterization only. Radiographs are made of the contrast- lled bladder and frequently of the contrast- lled urethra during voiding. Cystoscopy is required for location and catheterization of the vesicoureteral ori ces. 46. (B) Because the urinary structures have so little subject contrast, arti cial contrast material must be employed for better visualization of these structures. Contrast agents used for urographic procedures can have unpleasant, and (rarely) even lethal, side e ects. Intravenous injection of contrast frequently produces a warm,

ushed feeling, a bitter or metallic taste, or mild nausea. These side e ects are of short duration and usually pass as quickly as they come. More serious side e ects include urticaria, respiratory discomfort/distress, and, rarely, anaphylaxis. An antihistamine is appropriate treatment for simple side e ects, but the radiographer must always be prepared to deal quickly and e ciently with patients experiencing more serious reactions. Nonionic contrast agents are far less likely to produce side e ects. 47. (D) The most commonly performed radiologic examination of the reproductive system is hysterosalpingography, which is employed for evaluation of the uterus, oviducts, and ovaries of the female reproductive system. The procedure serves to delineate the position, size, and shape of the structures, and demonstrate pathology such as polyps, tumors, and stulas. However, it is most often used to demonstrate patency of the oviducts in cases of in ertility and is sometimes therapeutic in terms of opening a blocked oviduct. 48. (B) An anteroposterior (AP) postvoid bladder image is usually required to detect any residual urine in the evaluation of tumor masses or enlarged prostate glands. An erect image is occasionally requested to demonstrate renal mobility and ureteral tortuosity. 49. (A) During intravenous urography, both oblique positions are generally obtained. The 30º oblique KUB (kidney, ureters, bladder) places the kidney of the side away from the x-ray table parallel to the IR. The kidney closer to the x-ray table is placed perpendicular to the IR. The oblique positions provide an oblique projection of the urinary bladder. 50. (A) A 15º to 20º anteroposterior (AP) Trendelenburg position during intravenous (IV) urography is often helpful in demonstrating lling of the distal ureters and the area of the vesicoureteral ori ces. In this position, the contrast- lled urinary bladder moves superiorly, encouraging lling of the distal ureters and superior bladder, and provides better delineation of these areas. The central ray should be directed perpendicular to the IR. Compression of the distal ureters is used to prolong lling of the renal pelvis and calyces. Compression of the proximal ureters is not advocated. 51. (B) The CNS is enclosed within three tissue membranes, the meninges. The pia mater is the innermost vascular membrane, which is closely attached to the brain and spinal cord. The arachnoid mater is a thin layer outside the pia mater and attached to it by web-like bers. The

CHAPTER 6 IMAGING PRO CEDURES: ANATO MY, PO SITIO NING, AND PATHO LO GY

subarachnoid space is between the pia and arachnoid mater and is lled with cerebrospinal uid (CSF). The brain and spinal cord oat in CSF, which acts as a shock absorber. The dura mater is a double-layered brous membrane outside the arachnoid mater. The subdural space is located between the arachnoid and dura mater; it does not contain CSF. The epidural space is located between the two layers of dura mater. 52. (A) Anterior and posterior aspects of the stomach are visualized in the lateral position; medial and lateral aspects of the stomach are visualized in the AP projection. With the body in the AP recumbent position, barium ows easily into the undus of the stomach, displacing the stomach somewhat superiorly. The fundus, then, is lled with barium, while air is displaced into the gastric body, pylorus, and duodenum, demonstrating them as double contrast. Air-contrast delineation of these structures allows us to see through the stomach to the retrogastric areas and structures. 53. (C) Superimposition of bony details frequently makes angiographic demonstration of blood vessels less than optimal. The method used to remove these superimposed bony details is called subtraction. Digital subtraction can accomplish this through the use of a computer, but photographic subtraction may also be performed using images from an angiographic series. Registration is the process of matching one series image exactly over another. A reversal image, or positive mask, is a reverse of the black and white radiographic tones. 54. (A) Deoxygenated blood is returned by way of the inferior and superior vena cava to the right side of the heart. The blood is emptied into the right atrium, passes through the tricuspid valve, and enters the right ventricle. It is forced through the pulmonary semilunar valve into the pulmonary artery (by contraction of the right ventricle) and passes to the lungs for reoxygenation. From the lungs, it is collected by the pulmonary veins, which carry the oxygenated blood to the left atrium, where it travels through the mitral valve into the le t ventricle. Upon contraction of the left ventricle, blood passes through the aortic valve into the aorta and to all parts of the body. 55. (D) Generally, contrast medium is injected into the subarachnoid space between the third and fourth lumbar vertebrae. Because the spinal cord ends at the level of the rst or second lumbar vertebrae, this is considered to be a relatively safe injection site. The cisterna magna can be

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used, but the risk of contrast entering and causing side e ects increases. 56. (B) The heart wall is made up of the external epicardium, the middle myocardium, and the internal endocardium. The pericardium is the broserous sac enclosing the heart and roots of the great vessels. The heart has four chambers. The two upper chambers are the atria and the two lower chambers are the ventricles. The apex of the heart is the tip of the left ventricle. 57. (A) An intervertebral disk can rupture due to trauma or degeneration. The nucleus pulposus protrudes posteriorly through a tear in the annulus brosus and impinges on nerve roots and can be demonstrated by placing positive or negative contrast media into the subarachnoid space. Internal disk lesions can be demonstrated only by injecting contrast into the individual disks. (This procedure is termed diskography.) Anterior protrusion of a herniated intervertebral disk does not impinge on the spinal cord and is not demonstrated in myelography. 58. (C) Major branches of the common carotid arteries (internal carotids) function to supply the anterior brain, while the posterior brain is supplied by the vertebral arteries (branches of the subclavian arteries). The brachiocephalic (innominate) artery is unpaired and is one of three branches of the aortic arch, from which the right common carotid artery is derived. The left common carotid artery comes directly o the aortic arch. 59. (D) Venous blood is returned to the right atrium of the heart via the superior (from upper body) and in erior (from lower body) vena cavae and the coronary sinus (from the heart substance; see Fig. 6–118). Upon 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 to the lungs for oxygenation. Blood is returned via the pulmonary veins to the left atrium. During atrial systole, blood passes through the mitral (bicuspid) valve into the left ventricle. During ventricular systole, the oxygenated blood is pumped through the aortic semilunar valve into the aorta. 60. (C) The heart wall is made up of the external epicardium, the middle myocardium, and the internal endocardium. The pericardium is the broserous sac enclosing the heart and roots of the great vessels. The heart has four chambers. The two upper chambers are the atria, and the two lower chambers are the ventricles. The apex of the heart is the tip of the left ventricle.

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PART

III

Radiation Protection

CHAPTER 7 Radiation Protection Considerations

CHAPTER 8 Patient Protection

Ionizing Ef ects o X-Radiation Electromagnetic Radiation Production o X-Rays at the Tungsten Target Interactions Between X-Ray Photons and Matter Dose –Response Relationships Dose–Response Curves Linear: Threshold and Nonthreshold Nonlinear: Threshold and Nonthreshold Late E ects Types o Risk Biologic Ef ects o Ionizing Radiation Law o Bergonié and Tribondeau Radiation Weighting and Tissue Weighting Factors Linear Energy Trans er and Relative Biologic E ectiveness Versus Biologic Damage Molecular E ects o Ionizing Radiation Cellular and Relative Tissue Radiosensitivity Genetic Ef ects Pregnancy Females Males Children Genetically Signi cant Dose Somatic Ef ects Carcinogenesis Cataractogenesis Li espan Shortening Reproductive Risks Embryologic/Fetal E ects Acute Radiation Syndrome

Beam Restriction Purpose Types Light-Localization Apparatus Accuracy Exposure Factors mAs and kV Generator Type Filtration Inherent Filtration Added Filtration NCRP Guidelines Shielding Rationale or Use Types and Placement o Shields Patient Position Reducing Patient Exposure Patient Communication Positioning o Patient Automatic Exposure Control Image Receptors Grids and Air-Gap Technique Fluoroscopy NCRP Recommendations or Patient Protection

CHAPTER 9 Personnel Protection General Considerations Occupational Exposure ALARA Principle 227

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Occupational Radiation Sources Scattered Radiation Leakage Radiation NCRP Guidelines Fundamental Methods o Protection Cardinal Rules Inverse Square Law Primary and Secondary Barriers NCRP Guidelines Protective Apparel and Its Care Protective Accessories Special Considerations Pregnancy Mobile Units Fluoroscopic Units and Procedures

CHAPTER 10 Radiation Exposure and Monitoring Units o Measurement Roentgen/Gya Rad/Gray (Gyt ) Rem/Sievert Particulate Radiation Monitoring Devices National Council on Radiation Protection and Measurements (NCRP) Guidelines or Use Optically Stimulated Luminescence Film Badge Thermoluminescent Dosimeter Pocket Dosimeter Evaluation and Maintenance o Records NCRP Recommendations

Radiation Protection Considerations

7

OBJECTIVES At the conclusion o this chapter, the student will be able to: • • • • • • • • •

De ne terminology related to the electromagnetic spectrum. Discuss human exposure to types o background radiation. Describe the two processes o x-ray production. Describe the two major interactions between x-ray photons and tissue in diagnostic x-ray. Distinguish between deterministic and probabilistic e ects. Identi y dose–response curves and discuss the application(s) o each. Identi y the characteristics o cells/tissues that determine radiosensitivity. Describe the types o molecular e ects o ionizing radiation. Give examples o somatic versus genetic e ects.

IONIZINGEFFECTSOFX-RADIATION Electromagnetic Radiation A review o electromagnetic radiation and energy is essential to the study o x-rays and other orms o ionizing radiation. Electromagnetic radiation can be described as wave-like uctuations o electric and magnetic elds. T ere are several kinds o electromagnetic radiations. Figure 7–1 illustrates that 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 (186,000 miles per second); however, they di er signi cantly in wavelength and requency. Wavelength re ers to the distance between two consecutive wave crests (Fig. 7–2). 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.

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Figure 7–1. The electromagnetic spectrum. Frequency and photon energy are directly related; requency and photon energy are inversely related to wavelength.

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 (Fig. 7–1). Some radiations are energetic enough to rearrange atoms in the 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. X-ray photons, having the dual nature o both particles and electromagnetic waves, are highly energetic ionizing radiation. Diagnostic x-rays are extremely short, between 10−8 and 10−12 m in wavelength. T e unit ormerly used or such small dimensions is the angstrom (Å); 1 Å = 10−10 m. 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

+ 0 − Dis ta nce be twe e n cre s ts = wave le ngth

Time

Numbe r of cycle s pe r unit of time = fre que ncy

Time

A

+ 0 − B

Figure 7–2. Wavelength (A) versus requency (B). Wavelength is described as the distance between successive crests. The shorter the wavelength, the more crests or cycles per unit o time (e.g., per second). There ore, the shorter the wavelength, the greater the requency (number o cycles per second). Wavelength and requency are inversely related.

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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 materials 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 gases. In addition to natural background radiation, 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 manmade radiation exposure in the United States. In addition, NCRP Report No. 160 states that medical radiation exposure now contributes 50% o the public’s exposure to ionizing radiation (Fig. 7–3). NRC (Nuclear Regulatory Commission) regulations and radiation exposure limits are published in itle 10 o the Code o Federal Regulations (CFR), Part 20. Substances in consumer products such as tobacco, the domestic water supply, building materials, commercial air travel and, to a lesser extent, smoke detectors, televisions, and computer screens, account or 2%. Occupational exposures, allout, and the nuclear uel cycle comprise less than 1% o the manmade component. X-ray photons are manmade in nitesimal bundles o energy 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. 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 maniest within days a er the exposure. Late e ects such as cancer, which can occur a er more ordinary doses, may take many years to develop. Me dica l (Conve ntiona l ra diogra phy/fluoro) 5%

Cons ume r 2% Occupa tiona l