Clinical Atlas of CT Virtual Hysterosalpingography 3030662063, 9783030662066

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Patricia Carrascosa · Carlos Capuñay · Juan Mariano Baronio · Sergio Papier Editors

Clinical Atlas of CT Virtual Hysterosalpingography

123

Clinical Atlas of CT Virtual Hysterosalpingography

Patricia Carrascosa • Carlos Capuñay • Juan Mariano Baronio • Sergio Papier Editors

Clinical Atlas of CT Virtual Hysterosalpingography

123

Editors Patricia Carrascosa Medical Director Chief of the Research Department Diagnostico Maipú Vicente López, Argentina

Carlos Capuñay Chief of the Computed Tomography and Magnetic Resonance Imaging Department Diagnostico Maipú Vicente López, Argentina

Juan Mariano Baronio Fertility and Endoscopic Departments CEGYR Buenos Aires, Argentina

Sergio Papier Medical Director CEGYR Buenos Aires, Argentina

ISBN 978-3-030-66206-6 ISBN 978-3-030-66207-3 https://doi.org/10.1007/978-3-030-66207-3

(eBook)

© Springer Nature Switzerland AG 2021 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, expressed or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Illustrations by Daniel Cirigliano: Diagnóstico Maipú-DASA, Research Department Av. Maipú 1668, Vicente López, B1602ABQ, Buenos Aires, Argentina. This Springer imprint is published by the registered company Springer Nature Switzerland AG The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland

To my amazing husband German, for his love and unconditional support in every dream I had. To my dear children Belén and Juan Ignacio who have accompanied me in each project undertaken. To my prized brother Jorge who has been my mentor and guide in my professional carrier. To Diagnóstico Maipú that trusted and allowed me to develop this innovative technique together with my colleagues and friends Dr. Capuñay and Dr. Baronio. To my adored parents Mónica and Joaquín, who taught me that dedication and perseverance are the way to success. Patricia Carrascosa To Laura, for her love, patience and support. To my dearest children, Lucila, Agustina and Santiago, who give my life a sense of meaning and purpose. To Diagnóstico Maipú for the interest and support in this type of enterprises and to Dra. Carrascosa for the pleasure of sharing these years of work and friendship. Carlos Capuñay To my wife, Veronica, for her love, patience and encouragement. To my beloved children, Felicitas, Tobias and Catalina, who give sense on what is truly important in life. To my parents, Zulema and Emilio, my sister and brother, Maria Jose and Luis, for their education and endless support. To CEGYR and Diagnóstico Maipú, especially to Dra. Carrascosa and Dr. Capuñay for the joy of working together. Juan Mariano Baronio To Prof. Anibal Acosta (†), my friend, my mentor... Sergio Papier

Foreword

It is a great honor, and a real pleasure, to write a prologue for this excellent book on CT virtual hysterosalpingography (CT-VHSG). I am fully aware that often readers only take a quick glance, or even skip the prologue all together, so it is my purpose to keep it short and to the point. First and foremost, I wish to emphasize that the authors of this textbook are true experts on the use of this technique, as they pioneered this imaging modality to study the female reproductive tract almost two decades ago. In the process, they clearly mastered CT-VHSG, as they performed studies on more than 15,000 patients, clearly demonstrating that in comparison to the standard HSG, the virtual modality is less invasive, takes less time, generates less radiation, and, more importantly, has a much higher degree of accuracy. The format of this textbook is the presentation of clinical cases with a short introduction, including the CT technical features and radiation dose, followed by a review of the images pertinent to the case, closing with findings and interpretation of the various images presented, as multiplanar reconstruction, maximum intensity projection, volume rendering, and virtual endoscopy, with images that are truly amazing. Uterine anomalies, myomas, polyps, tubal disease, etc. are thoroughly discussed and should be of great educational value to all reproductive surgeons. Congratulations to the authors and thank you for sharing your large experience. I am sure your readers will find this material essential, as they become familiar with this relatively new technique. Carlos E. Sueldo, MD Professor and Chair Obstetrics and Gynecology Department University of California San Francisco, CA, USA e-mail: [email protected]

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Preface

The female reproductive system is a complex anatomical region in the human body. Throughout the last decades new advances in the understanding of the causes of infertility and of assisted reproductive technology have resulted in the development of novel diagnostic tools for an accurate evaluation of the gynecologic system. Trying to solve this challenge, in 1998, we began at Diagnóstico Maipú, a medical imaging center in the northern area of Greater Buenos Aires, a journey looking for a diagnostic study that would provide these solutions. These were the first steps in the development of a novel diagnostic imaging technique that today, after more than 20 years of experience, is known as computed tomography virtual hysterosalpingography (CT-VHSG). This diagnostic technique allows the evaluation of the entire gynecologic tract in a single study, with a complete visualization of the uterine cavity, fallopian tubes, and extrauterine structures. CT-VHSG combines all the benefits of the multidetector computed tomography, including a low-dose radiation exposure and the advantages of all the image post-processing tools such as multiplanar reconstructions, three-dimensional images, and a virtual navigation within the uterus and fallopian tubes, allowing an integral vision of the gynecologic system. This illustrated atlas is committed to a vision of interdisciplinary and multimodality approach in the evaluation of the female reproductive system. Our goal was to create a comprehensive and educational tool focusing on the normal anatomy, the diverse gynecologic pathologies, and also potential pitfalls of the technique. Each chapter was designed with a brief anatomical, pathological, and radiological review, followed by a series of carefully selected illustrative and representative cases, with a detailed description of the imaging technique and major imaging findings. Each chapter may be read by itself and major contemporary references are given. The Clinical Atlas of CT Virtual Hysterosalpingography is intended for residents and specialists, in general, diagnostic radiology, fellows in gynecologic imaging, gynecologist, and specialists in reproductive medicine. We hope all of them will benefit from this huge effort. Vicente López, Argentina Buenos Aires, Argentina

Patricia Carrascosa Carlos Capuñay Juan Mariano Baronio Sergio Papier

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Contents

Computed Tomography Virtual Hysterosalpingography . . . . . . . . . . . . . . . . . . . . Carlos Capuñay and Patricia Carrascosa

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Normal Radiologic Anatomy of Female Reproductive System . . . . . . . . . . . . . . . . Patricia Carrascosa and Carlos Capuñay

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Evaluation of the Cervix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Patricia Carrascosa and Carlos Capuñay

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Pathology of the Uterine Cavity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Carlos Capuñay, Patricia Carrascosa, and Juan Mariano Baronio

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Pathology of the Uterine Wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 Patricia Carrascosa and Carlos Capuñay Congenital Uterine Anomalies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233 Patricia Carrascosa and Carlos Capuñay Pathology of the Fallopian Tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285 Patricia Carrascosa, Carlos Capuñay, and Juan Mariano Baronio Morphological Post-surgical Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331 Carlos Capuñay and Patricia Carrascosa Pitfalls and Incidental Findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371 Carlos Capuñay and Patricia Carrascosa Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403

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Contributors

Juan Mariano Baronio, MD Fertility and Endoscopic Departments, CEGYR, Ciudad Autónoma de Buenos Aires, Argentina. Viamonte 1432, (C1055 ABB) Ciudad Autónoma de Buenos Aires, Argentina. [email protected] Carlos Capuñay, MD Head of Computed Tomography and Magnetic Resonance Imaging Department and Sub-Head Research Department, Diagnóstico Maipú-DASA, Buenos Aires, Argentina. Av. Maipú 1668, (B1602 ABQ), Vicente López, Buenos Aires, Argentina. [email protected] Jimena B. Carpio, MD Staff Physician, Computed Tomography and Magnetic Resonance Imaging Department, Diagnóstico Maipú-DASA, Buenos Aires, Argentina. Av. Maipú 1668, (B1602 ABQ), Vicente López, Buenos Aires, Argentina. [email protected] Patricia Carrascosa, MD, PhD, FSCCT, FACC, MSCCT Medical Director and Head of Research Department, Diagnóstico Maipú-DASA, Buenos Aires, Argentina. Av. Maipú 1668, (B1602 ABQ), Vicente López, Buenos Aires, Argentina. [email protected] Pamela Inés Causa Andrieu, MD Assistant Attending at Radiology service, section of Female Pelvic Imaging. Hospital Italiano of Buenos Aires, Argentina. Nuclear Oncology Imaging Fellow. Memorial Sloan Kettering Cancer Center, United States. Pres. Tte. Gral. Juan Domingo Perón 4190 (C1199 ABH), Ciudad Autónoma de Buenos Aires, Argentina. [email protected] Carolina Rosa Beatriz Chacón, MD Attending. Chief of Ultrasound and Female Pelvic Imaging sections. Diagnostic Imaging Department. Hospital Italiano of Buenos Aires, Argentina. Pres. Tte. Gral. Juan Domingo Perón 4190 (C1199 ABH), Ciudad Autónoma de Buenos Aires, Argentina. [email protected] Angela de Figueiredo Pinto Agostini, MD Pontifícia Universidade Católica do Rio Grande do Sul, Hospital São Lucas. Centro de Diagnóstico por imagem. Av. Ipiranga, 6690. Térreo, setor de radiologia. Jardim Botânico, Porto Alegre - RS, Brasil. 90610-000. [email protected]

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Guilherme Galante Heuser, MD, M.Sc Universidade Regional do Noroeste do Rio Grande Do Sul – UNIJUÍ – Departamento de ciências da vida – Faculdade de Medicina. Instituto de Medicina e Diagnóstico por Imagem – IMED Radiologia Rua Theodorico Fricke, 300, São Geraldo, Ijuí – RS, Brazil. CEP 98700-000 [email protected] Henrique Galante Heuser, MD Instituto de Medicina e Diagnóstico por Imagem – IMED Radiologia Hospital Unimed Noroeste RS, departamento de Radiologia. Rua Pedro Hammastron 287, Hammastron, Ijuí – RS, Brazil. CEP 98700-000 [email protected] Mara Lía Gómez, MD Assistant Attending at Radiology service, section of Female Pelvic Imaging. Diagnostic Imaging Department. Hospital Italiano of Buenos Aires, Argentina. Pres. Tte. Gral. Juan Domingo Perón 4190 (C1199 ABH), Ciudad Autónoma de Buenos Aires, Argentina. [email protected] Manoel Afonso Guimarães Gonçalves, MD, PhD Pontifícia Universidade Católica do Rio Grande do Sul, Hospital São Lucas, departamento de ginecologia e obstetrícia Av. Ipiranga, 6690. Centro clínico, cj 217. Jardim Botânico, Porto Alegre - RS, Brasil. 90610-000. [email protected] Tassia Machado Medeiros, MD, PhD Universidade Regional do Noroeste do Rio Grande Do Sul – UNIJUÍ – Departamento de ciências da vida – Faculdade de Biomedicina. Hospital Unimed Noroeste RS, departamento de Radiologia. Rua Pedro Hammastron 287, Hammastron, Ijuí – RS, Brazil. CEP 98700-000 [email protected] María Noelia Napoli, MD Assistant Attending at Radiology service, section of Female Pelvic Imaging. Diagnostic Imaging Department. Hospital Italiano of Buenos Aires, Argentina. Pres. Tte. Gral. Juan Domingo Perón 4190 (C1199 ABH), Ciudad Autónoma de Buenos Aires, Argentina. [email protected] José M. Palacios-Jaraquemada, MD, Ph.D CEMIC University Hospital. Buenos Aires, Argentina. Galván 4102 (C1431FWO), Ciudad de Buenos Aires, Argentina. [email protected] Sergio Papier, MD Reproductive Medicine Specialist. Medical Director of CEGYR (Center of studies on Genetics and Reproduction), Ciudad Autónoma de Buenos Aires, Argentina. Past President of SAMER (Argentine Society of Reproductive Medicine) and ALMER (Latinamerican Association of Reproductive Medicine). Viamonte 1432, (C1055 ABB) Ciudad Autónoma de Buenos Aires, Argentina. [email protected] Alvaro Petracco, MD, PhD Fertilitat- Centro de Medicina Reprodutiva Rua Gomes Jardim, 201 Torre Norte, 15º andar - Santana, Porto Alegre - RS, Brasil. 91530-001 [email protected]

Contributors

Contributors

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Marta Ribeiro Hentschke, MD, PhD Pontifícia Universidade Católica do Rio Grande do Sul, Hospital São Lucas, departamento de ginecologia e obstetrícia; Fertilitat- Centro de Medicina Reprodutiva Rua Gomes Jardim, 201 Torre Norte, 15º andar - Santana, Porto Alegre - RS, Brasil. 91530-001 [email protected] Lorena I. Sarati, MD Staff Physician, Computed Tomography and Magnetic Resonance Imaging Department, Diagnóstico Maipú-DASA, Buenos Aires, Argentina. Av. Maipú 1668, (B1602 ABQ), Vicente López, Buenos Aires, Argentina. [email protected] Marina Ulla, MD Attending. Chief of Computed Tomography and Body Imaging sections. Chief of Medical Informatics. Diagnostic Imaging Department. Hospital Italiano of Buenos Aires, Argentina. Pres. Tte. Gral. Juan Domingo Perón 4190 (C1199 ABH), Ciudad Autónoma de Buenos Aires, Argentina. [email protected] Heron Werner Jr., MD Specialist in Gynecology, Obstetrics and Ultrasound (FEBRASGO and Brazilian College of Radiology). MSc in Obstetris - Federal University of Rio de Janeiro (UFRJ). PhD in Radiology - Federal University of Rio de Janeiro (UFRJ). Physician “Assistant Étranger”- Université René Descartes (Paris V). Visiting Professor Lectureship - The Children's Hospital of Philadelphia (CHOP) USA. Av. Carlos Peixoto 80/401 Botafogo, 22290-090 Rio de Janeiro, Brazil [email protected]

Computed Tomography Virtual Hysterosalpingography Carlos Capuñay and Patricia Carrascosa

Computed tomography virtual hysterosalpingography (CT-VHSG) is a novel radiographic technique for evaluating the female reproductive system. Based on a CT volumetric data of the pelvic region, this diagnostic procedure combines the advantages of multidetector CT and the capabilities of the X-ray hysterosalpingography (HSG) for an exhaustive and complete evaluation of the gynecologic system in one study [1–4]. The main clinical indication for CT-VHSG is infertility. Other indications include recurrent spontaneous abortion, patient’s evaluation prior assisted fertilization treatment, preoperative evaluation of patients with myomas, characterization of congenital uterine anomalies, and postsurgical assessment among others [3]. In the last two decades, the development and improvement of multidetector CT technology have widely expanded its diagnostic capabilities. Based on an exceptionally high spatial and temporal resolutions, the isotropic data acquisition is feasible for nearly every application [5–8]. But it was only when the 64 or more detector row CT scanners emerged that this new procedure became clinically useful and a reliable, superior, and more comprehensive diagnostic tool than the conventional X-ray HSG exam [3, 9]. The analysis of the thin axial CT images, multiplanar reformats in any plane, three-dimensional reconstructions, and virtual endoluminal views provides a detailed evaluation of the cervix, uterus, and tubes, as well as additional information of the surrounding intrapelvic structures [10, 11].

C. Capuñay (&) Computed Tomography & Magnetic Resonance Imaging Department and Research Department, Diagnóstico MaipúDASA, Av Maipu 1668, Vicente López, Buenos Aires, B1602ABQ, Argentina e-mail: [email protected] P. Carrascosa Medical Director and Research Department, Diagnóstico MaipúDASA, Av. Maipú 1668, Vicente López, Buenos Aires, B1602ABQ, Argentina e-mail: [email protected]

Patient Preparation The procedure must be performed between the 6th and 11th day of the menstrual cycle, during the early proliferative phase. The patient should abstain from sexual intercourse from the cessation of menstrual bleeding until 48 h of completion of the imaging exam. She must drink a liter of water one hour prior to appointment time, and hold. A 4-h fast to solids is preferable. Taking a nonprescription pelvic pain reliever such as ibuprofen is optional. Prophylactic administration of antibiotics is not indicated.

The Day of the Exam The patient must sign an informed consent that will be delivered to the physician prior to start the CT-VHSG procedure. It is important that the patient has the opportunity to talk to the radiologist about the procedure and clarify all her doubts before giving her consent. In the CT room, previous administration of intramuscular antispasmodic medication if no contraindications exist, the patient is positioned supine on the CT table in the lithotomy position, with the knees flexed over the table (Fig. 1). The perineum is cleansed with a povidone-iodine solution, draped with sterile towels, and a disposable plastic speculum is inserted into the vagina. Using an external light (flashlight), the physician is able to see the uterine cervix. Povidone-iodine solution cleaning with sterilized gauze of the external cervical os is performed [3]. Each CT-VHSG examination starts with the acquisition of both a lateral and anterior-posterior topograms for planning the CT scan (Fig. 2). It is important to locate in these scout views the end of the speculum, as it serves as a guide to establish the beginning of the CT scan. The scan length is

© Springer Nature Switzerland AG 2021 P. Carrascosa et al. (eds.), Clinical Atlas of CT Virtual Hysterosalpingography, https://doi.org/10.1007/978-3-030-66207-3_1

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Fig. 1 Patient on the CT table in the lithotomy position, with the knees flexed over the table

routinely fixed in 10 cm, since this length allows to cover the whole gynecological system in almost all patients. Back in the CT room, a plastic cannula is placed in the external cervical orifice and attached to the speculum by a clamping device specially designed for this purpose (US patent; Fig. 3). The size of the cannula depends on the morphology and diameter of the external cervical os, ranging from 12 to 16 F. The most commonly used size in the majority of the patients is the 16 Fr. A total of 15–20 mL of a mixture of iodinated contrast and saline solution is injected at a dilution of 70%, using a power injector at a rate of 0.3 mL/sec. The CT image acquisition initiates 30–40 seconds after the contrast material instillation begins. Once the CT scan is acquired, the radiologic technologist evaluates how the patient feels as well as the radiologist reviews the obtained images to assure they have performed satisfactory and that are suitable for diagnosis. If necessary, a new CT image acquisition will be made. On the contrary, all equipment used in the diagnostic procedure are removed, the perineum

Fig. 2 Lateral (a) and anterior-posterior (b) CT topograms, also known as pilot scans or scout views for CT scan planning. A 10 cm length field of view is marked by the white rectangle

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is cleansed with a povidone-iodine solution, and a sterile dressing is left, so that the patient can later remove it when dressing. Before leaving the CT room, the patient is informed that she may experience slight vaginal spotting and pelvic pain similar to a menstrual period for 1 day after the procedure. And in case that any other signs or symptoms, such as heavy bleeding, fever, or increased pelvic pain, start, they may be related to other complications and she should contact the office immediately.

Technical Parameters As previously mentioned, 64 or more row CT scanners are mandatory to perform the CT-VHSG procedure. This is because an acquisition time of less than 5 seconds is indispensable for an optimal visualization of the fallopian tubes [12–14].

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Fig. 3 Clamping device specially designed to fix the cannula (a, b). The device is attached to the speculum and fixes the cannula in the center (c)

Technical parameters must be adjusted according to the CT scanner. The following technical parameters are suggested for image data acquisition on a 64-row CT scanner: detector collimation, 64  0.625 mm; slice thickness, 0.625 mm; reconstruction interval, 0.315 mm; 80–100 kV (depending on body size, body habitus, and body mass index); 100–250 mAs, with automatic tube current modulation. Total scan time is 3–4 seconds. Iterative reconstruction if available is preferred over the filter back projection reconstruction algorithm, improving image quality by reducing image noise and also giving the possibility to further reduce radiation dose in these studies [15]. The current estimated radiation dose is about 0.3– 0.5 mSv.

Image Reprocessing and Analysis Acquired images are transferred to the PACS (picture archiving and communication system). Using a dedicated workstation, different post-processing algorithms can be used for image analysis and interpretation, including Fig. 4 Axial multiplanar reconstruction with soft-tissue window (width: 350–400; level: 20–60) depicts the myometrial wall and the intrapelvic structures (a). For a better evaluation of the uterine lumen and fallopian tubes, a wide window (width: 450–600; level: 3000–3500) is recommended (b)

multiplanar reformation (MPR), maximum intensity projection (MIP), volume rendering, and virtual endoscopy [16, 17].

Multiplanar Reformation This imaging reprocess uses the data from axial CT images to create non-axial two-dimensional images. Sagittal, coronal, and oblique reconstructions with soft-tissue window are utilized for the assessment of the uterus, fallopian tubes, and extra-uterine structures. Curve MPRs get virtually straightened images of curvilinear structures from isotropic volumetric CT data. Using this algorithm, the cervix and uterus can be uncoiled in a single continuous plane, obviating a physical manipulation or retraction of the uterus during the procedure [9]. On the other hand, it helps in a better appreciation of the whole female reproductive system avoiding overlap between anatomic structures (Figs. 4 and 5). MPR images enable accurate measurements either length, size, or angles of any anatomical structures, as well as any lesions as polyps, myomas, etc. [18–20].

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Maximum Intensity Projection This algorithm tends to display only pixels with high Hounsfield numbers from a volume of CT data, and other lower attenuation structures are not well visualized. This helps to obtain two-dimensional grayscale images of the cervix, uterus, and, particularly, the fallopian tubes. Normal tubes are thin and difficult to identify on axial or MPR images. MIP sections of variable thickness are excellent for assessing the size and location of the tubes, as well as identifying diverse pathologies as tubal occlusion, ampullar dilatation, or hydrosalpinx (Fig. 6). Nonetheless, because multiple slices are combined in the MIP display, intrauterine lesions can potentially be hidden and undiagnosed.

volumetric two-dimensional axial CT data. Based on the nature of the data at each voxel, colors and opacities are assigned and all the structures (the surface and the underlying structures) are visualized according to the optical behavior of their components. With volume rendering, the entire three-dimensional dataset of the gynecologic system is seen in one piece, including the endoluminal information. It contributes to the detection and characterization of a wide spectrum of pathologies such as cervical stenosis, endometrial polyps, and hydrosalpinx (Fig. 7). It is important to note that volume rendering can obscure pathology when the uterus is not properly distended.

Virtual Endoscopy Volume Rendering Volume rendering is a data visualization technique which provides a three-dimensional representation of the

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This method produces endoscope-like displays of the interior of a hollow anatomic structure, providing endoluminal information similar to a conventional hysteroscopy. Images can be obtained at different angles and orientations, and the

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Fig. 5 Axial (a), coronal (b), and sagittal (c) multiplanar reconstructions allow the entire bidimensional evaluation of the uterus. Using the curve multiplanar algorithm the cervical canal and uterine cavity can be displayed altogether in the same plane (d)

Fig. 6 Thick slab (a) or three-dimensional (b, c) maximum intensity projections allow the assessment of the uterine cavity shape and size, as well as detailed evaluation of the fallopian tubes

Computed Tomography Virtual Hysterosalpingography

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Fig. 7 Volume rendering images are three-dimensional reconstructions that provide detailed information of the cervical canal (arrow), uterine cavity (asterisk) and fallopian tubes (arrowheads) (a).

They display normal findings, as cervical folds (arrow) (b) or pathology such as the presence of endometrial polyps (arrows) (c)

intraluminal navigation can be from the cervix to the uterine fundus or vice versa (Fig. 8). This post-processing algorithm complements the other visualization techniques and enables verification of questionable findings [21].

history of adverse reactions to iodinated contrast media or of foods or medicine allergies [22].

Complications The overall risk of complications is low. The limited manipulation of the cervix during the exam, the no clamping or retraction of the uterus or occlusion of the cervix minimizes the risk of bleeding and infection. Vasovagal reactions are extremely rare. Complications related to the contrast agent are also exceptional due to the use of a 70% dilution of a hydrosoluble, nonionic, low-osmolality iodine contrast media at a very slow injection rate. A gadolinium-based contrast agent is an alternative in patients with previous

Contraindications Absolute contraindications include acute pelvic infection and pregnancy. Relative contraindications are chronic pelvic infection, intrapelvic inflammation, and recent uterine or tubal surgery [3].

Patients’ Acceptance and Discomfort Since the concept of non-invasive study, CT-VHSG is a diagnostic procedure very well tolerated by patients. Based on an experience including 11500 CT-VHSG studies, patients were questioned about the level of

Fig. 8 Virtual endoscopy views display an endoluminal vision of the cervical canal (a) and the entire endometrial cavity (b, c)

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discomfort during the exam. A 5-point scale is used to classify discomfort: level 0, no discomfort; level I, slight discomfort; level II, moderate discomfort; level III, severe discomfort; and level IV, intolerable discomfort. The 81% of the patients classified it as level 0, 11% as level I, 4.5% as level II, 2.5% as level III, and 1% as level IV. Those women who had already done a conventional HSG demonstrated better acceptance than those where CT-VHSG was their first study of its kind. This could be due to higher expectations for the new method and the impossibility of comparison with the conventional exam.

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to screen for colorectal neoplasia in asymptomatic adults. N Engl J Med. 2003;349(23):2191–200. Crossref, Medline, Google Scholar. Carrascosa P, Capuñay C, Baronio M, Martín López E, Vallejos J, et al. 64-row multidetector CT virtual hysterosalpingography. Abdom Imaging 2009;34(1):121–133. Crossref, Medline, Google Scholar. Kulama E. Scanning protocols for multislice CT scanners. Br J Radiol. 2004;77:S2–9. Mc Collough CH, Zink FE. Performance evaluation of a multi-slice CT system. Med Phys. 1999;26:2223–30. Mori S, Endo M, Tsunoo T, Kandatsu S, Tanada S, Aradate H, et al. Physical performance evaluation of a 256-slice CT-scanner for four-dimensional imaging. Med Phys. 2004;31(6):1348–56. Endo M, Mori S, Kandatsu S, Tanada S, Kondo C. Development and performance evaluation of the second model 256-detector row CT. Radiol Phys Technol. 2008;1(1):20–6. Ritschl L, Sawall S, Knaup M, Hess A, Kachelriess M. Iterative 4D cardiac micro-CT image reconstruction using an adaptive spatio-temporal sparsity prior. Phys Med Biol. 2012;57(6):1517– 25. Beister M, Kolditz D, Kalender WA. Iterative reconstruction methods in X-ray CT. Phys Med. 2012. Sebastian S, Kalra MK, Mittal P, Saini S, Small WC. Can independent coronal multiplanar reformatted images obtained using state-of-the-art MDCT scanners be used for primary interpretation of MDCT of the abdomen and pelvis? A feasibility study. Eur J Radiol. 2007;64(3):439–46. Kirchgeorg MA, Prokop M. Increasing spiral CT benefits with postprocessing applications. Eur J Radiol. 1998;28(1):39–54. Review. Baronio M, Carrascosa P, Capuñay C, et al. Diagnostic performance of CT virtual hysteroscopy in 69 consecutive patients. Fertil Steril. 2010;94(Supplement):S77. Capuñay C, Baronio M, Carrascosa P, et al. CT virtual hysterosalpingography in the evaluation of uterine myomas. Fertil Steril. 2010;94(Supplement):S211. Carrascosa P, Baronio JM, Borghi M, et al. Histerosalpingoscopía virtual. Una técnica novedosa y no invasiva para diagnosticar patología intrauterina. Reproducción 2006;21:19–26. Chalazonitis A, Tzovara I, Laspas F, et al. Hysterosalpingography: technique and applications. Curr Probl Diagn Radiol. 2009;38 (5):199–205. Silberzweig JE, Khorsandi AS, Caldon M. Alam S Gadolinium for hysterosalpingography. J Reprod Med. 2008;53(1):15–9.

Normal Radiologic Anatomy of Female Reproductive System Patricia Carrascosa and Carlos Capuñay

Uterus The uterus is a muscular, hollow, pear-shaped organ with its base positioned cranially, and located in the lower pelvis behind the bladder and in front of the rectum. Its size varies depending on individual’s age, hormonal status and obstetric history; in nulliparous women it measures approximately 75  45  33 mm in length, width and anteroposterior diameter respectively. It consists of four main anatomical sections including the cervix, isthmus, body and fundus. The uterine horns are the upper corners of the uterus into which the fallopian tubes enter. Its histology consists of three major layers: (a) the outer most layer is the perimetrium, a serous membrane referring to the visceral peritoneum; (b) the myometrium, which constitutes the middle layer and comprises a complex of three smooth muscle layers; (c) the inner most layer is the endometrium, the uterine mucous containing numerous tubular glands [1].

Position of the Uterus The position of the uterus varies according the angulation of the long axis of the uterus in relation to the vagina (version) and the corpus in relation to the cervix (flexion) [2]. In most women, the long axis of the uterus is flexed forward over the vagina and the uterine body is bent forward over the cervix P. Carrascosa (&) Medical Director and Research Department, Diagnóstico MaipúDASA, Av. Maipú 1668, Vicente López, Buenos Aires, B1602ABQ, Argentina e-mail: [email protected] C. Capuñay Computed Tomography & Magnetic Resonance Imaging Department and Research Department, Diagnóstico MaipúDASA, Av. Maipú 1668, Vicente López, Buenos Aires, B1602ABQ, Argentina e-mail: [email protected]

(anteversion-anteflexion). Other uterine positions can be present as normal variants (Fig. 1).

Cervix and Isthmus The cervix (or uterine neck) lies subperitoneally and is the lowest fibromuscular region of the uterus. Its average length is 40 mm and diameter 25 mm. It consists of a lower part projecting into the vagina denominated vaginal portion or tenca snout and a part an upper fixed in the parametrium, the supravaginal portion that joins the muscular body of the uterus in the isthmic region, at the level of the internal cervical orifice [1]. The size and shape of the cervix varies according to age, menstrual cycle and number of pregnancies. In nulliparous women, the neck is fusiform with a small, round external os located in the center; in a primiparous or multiparous women the cervical volume increase and the external os presents the aspect of a wide elongated cleft. The cervical canal communicates the vagina with the uterine cavity through the internal and external cervical os. As the rest of the cervix, its length and diameter vary according to the age and patient’s hormonal status. The epithelium presents multiple longitudinal folds that project towards the lumen of the canal and give place to papillary projections and invaginations that constitute endocervical glands. The isthmus is a 10 mm long narrow passage connecting the upper part of the cervix and the lower segment of the uterine body.

Body and Fundus The uterine corpus, the main portion of the uterus, lies intraperitoneally and has a triangular inverted shape single cavity covered by the endometrium. It starts just below the

© Springer Nature Switzerland AG 2021 P. Carrascosa et al. (eds.), Clinical Atlas of CT Virtual Hysterosalpingography, https://doi.org/10.1007/978-3-030-66207-3_2

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Fig. 1 Position of uterus in the pelvis determined by the orientation of the cervical neck in relation to the vagina and of the body in relation to the cervical neck. Anteversio-anteflexio uterus (a), anteversio-retroflexio uterus (b), retroversio-anteflexio uterus (c), retroversio-retroflexio uterus (d)

level of fallopian tubes up to the isthmus. The fundus conforms the upper dome-like portion of the uterus. It is a broad curve area and each lateral parts are called the cornual region or horn of the uterus, the site where the uterine cavity connects to the lumen of a fallopian tube [3]. The external configuration of the uterus is the final result of a complete fusion of the müllerian ducts during the embrionary period, and it has an utmost importance in the classification of uterine malformations. Any alterations in the process of fusion, as well as any in the process of septum reabsorption, originate to the different uterine malformations [2, 4–6]. Remnants of the fusion of both Müller ducts during the fetal development may be present in adulthood as prominent longitudinal folds parallel to the larger axis of the endometrial cavity. They should be considered as normal findings on CT-VHSG exam, and not associated with any endometrial pathology [7, 8].

Fallopian Tubes Fallopian tubes have tubular configuration and they are located on the top of the broad ligaments of the uterus. In the majority of women, they extend laterally and inferiorly from the uterine horn up to the ovaries. They are from 8 to 15 cm in length and they are divided in four anatomic segments (Fig. 2): A. The interstitial or intramural: it is of 1–2 cm length and 1 mm diameter. This segment is within the uterine wall, surrounding by myometrium. B. The isthmus: short segment, with the narrowest diameter and a thick wall. C. The ampulla: the widest and longest segment, representing over half the length of the tube (approximately

5 cm). It has a thin wall and its lumen enlarges gradually from the isthmus to the infundibulum, reaching a diameter between 6 and 10 mm. D. The infundibulum: the distal end of the tube. It has a funnel shape and frond-like projections or fimbriae [9]. The Fallopian tube wall has three layers. The inner most layer is the mucosa, with folds projecting towards the lumen, that increase in complexity as the end of the tube is approached, continuing them with the fimbriae. The muscular layer is composed of the circular and longitudinal muscle fibers. The outer most layer is the serosa. On CT-VHSG exams, normal uterine tubes are thin tubular structures emerging from the cornual region of the uterine cavity and extending towards peritoneal cavity. Their course and position within the pelvis are extremely variable. According to the tubal segment, the caliber of the opacified tubal lumen varies as mentioned earlier. In a variable number of examinations, oblique linear lucencies can be identified at the cornual-tubal junction, corresponding to non-pathologic muscular contractions. Using curve multiplanar reconstructions, the uterine tube is uncoiled in one plane and the lumen caliber is accurate measured. Tubal folds are seen usually in the ampullar region as lineal filling defects. In patients with patent tubes, the instilled contrast dilution opacifies all its length and spillages into the peritoneal cavity through the infundibulum. The contrast distribution pattern in the peritoneal cavity depends on the amount of contrast dilution administered, the time interval between the beginning of the injection and the CT image acquisition, and presence or absence of pathology. Incomplete opacification or lack of passage of the contrast into the peritoneal cavity are not infrequent and do not necessarily suggest pathology. A cornual spasm, mucous plugs or insufficient contrast instillation can simulate a tubal obstruction [8].

Normal Radiologic Anatomy of Female Reproductive System Fig. 2 Anatomic segments of the Fallopian tube

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Case 1 P. Carrascosa, M. Baronio, C. Capuñay Normal Anatomy Clinical History • Thirty-five-years-old female with primary infertility of 12 months duration. • Past medical history of oral contraceptive pills for contraception during 12 months. • Previous exams: normal conventional hysterosalpingography.

• CT-VHSG indication: evaluation of the reproductive system as the first line diagnostic imaging test in the infertility work-up. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time • Effective radiation dose: 0.3 mSv. Images

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Normal Radiologic Anatomy of Female Reproductive System

Findings and Interpretation Conventional hysterosalpingography frontal view (Fig. A) shows a uterine cavity with normal morphology (asterisks) as well as normal fallopian tubes (arrows) and passage of contrast in the peritoneal cavity (arrowhead). CT-VHSG coronal maximum intensity projection (Fig. B) displays an endometrial cavity of usual shape and size (asterisk) and

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patent fallopian tubes (arrows) with normal spillage of contrast into the peritoneal cavity with bilateral positive Cottè test (arrowheads). Volume rendering image (Fig. C) demonstrates the inverted triangular shape of the normal uterine cavity. Virtual endoscopy views at the uterine fundus (Fig. D) and at each uterine cornu (Figs. E and F), and conventional hysteroscopy images (Figs. G, H and I) at the same locations show normal endoluminal findings.

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Case 2 P. Carrascosa, C. Capuñay Normal Anatomy Clinical History • Thirty-three-years-old female with primary infertility of 33 months duration. • No relevant past medical or surgical history. • Previous exams: normal transvaginal ultrasound performed as the first line diagnostic imaging test in the infertility work-up.

• CT-VHSG indication: evaluation the cause of infertility. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time • Effective radiation dose: 0.3 mSv. Images

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Normal Radiologic Anatomy of Female Reproductive System

Findings and Interpretation CT-VHSG coronal maximum intensity projection with bone sculpting (Fig. A) shows a normal uterine cavity with regular margins and nicely depicts both fallopian tubes (arrows). Thick slab coronal maximum intensity projections at different angles (Figs. B and C) reveal a normal cervix, uterine cavity and fallopian tubes (arrows) with bilateral spillage of contrast into the

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peritoneal cavity with positive Cottè test (asterisks). Thick slab sagittal maximum intensity projection (Fig. D) displays an anteverted uterus with normal size and shape. Volume rendering images (Figs. E and F) show the normal anatomy of the reproductive system, with patent fallopian tubes (arrows) and normal spillage of contrast into the peritoneal cavity (asterisks). Virtual endoscopy views display the normal lumen of the cervical canal (Fig. G) and of the endometrial cavity (Figs. H and I).

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Case 3 P. Carrascosa, M. Baronio, C. Capuñay Normal Anatomy Clinical History • Twenty-seven-years-old female with primary infertility of 12 months duration. • No relevant past medical or surgical history. • Previous exams: normal transvaginal ultrasound as the initial imaging method in the fertility work-up.

• CT-VHSG indication: evaluation the cause of infertility and rule out associated pathology. • CT-VHSG was performed with a 64-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 150 mAs – 3.16 s scan time • Effective radiation dose: 0.5 mSv. Images

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Normal Radiologic Anatomy of Female Reproductive System

Findings and Interpretation CT-VHSG coronal maximum intensity projection (Fig. A) and three dimensional volume rendering images in gray scale (Fig. B) and color scale (Figs. C and D) show a normal cer-

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vical canal and endometrial cavity of normal size and shape. Both fallopian tubes are in detail visualized in both types of image reconstructions (arrows). Virtual endoscopy view (Fig. E) and conventional hysteroscopy correlation (Fig. F) display a normal endometrial cavity, fundus and uterine horns.

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• • • •

Case 4 P. Carrascosa, C. Capuñay Normal Anatomy Clinical History • Thirty-two-years-old female with secondary infertility of 12 months duration. • Previous exams: normal transvaginal ultrasound as the initial imaging method in the fertility work-up. • CT-VHSG indication: further evaluation to determine the cause of infertility and to rule out pathology.

Obstetric history: G1P1. No relevant past medical or surgical history. CT-VHSG was performed with a 64-slice CT scanner. CT technical parameters: – 0.9 mm slice thickness – 0.45 mm reconstruction interval – 100 kV – 150 mAs – 3.16 s scan time • Effective radiation dose: 0.9 mSv.

Images

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Findings and Interpretation Sagittal (Fig. A) and transverse (Fig. B) transvaginal ultrasound images show a normal size uterus with typical sonographic endometrial and myometrial appearance. CT-VHSG thick slab coronal multiplanar reconstruction (Fig. C) and coronal maximum intensity projections (Figs. D and E) display an endometrial cavity of normal size and shape, with patent fallopian tubes (arrows) and the presence of contrast material in the peritoneal cavity (asterisks) with positive

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L

Cottè test. Volume rendering image, inferior view without bone sculpting (Fig. F) shows the position of the uterus within the pelvis. Volume rendering image with bone sculpting, at lateral (Fig. G), inferior (Fig. H) and superior (Figs. I and J) views with different windowing settings reveal a uterus in retroversion-anteflexio position, with normal cervix, uterine cavity and fallopian tubes (arrows) and bilateral spillage of contrast into the peritoneal cavity with positive Cottè test (asterisks). Virtual endoscopy views (Figs. K and L) display a normal endometrial cavity.

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Case 5 P. Carrascosa, M. Baronio, C. Capuñay Normal Anatomy Clinical History • Thirty-six-years-old female with secondary infertility of 18 months duration. • Obstetric history: G1C1; cesarean delivery 3 years ago without complications. • No relevant past medical or surgical history.

• Previous exams: normal conventional hysterosalpingography performed 4 years ago. • CT-VHSG indication: evaluation to determine the cause of infertility. • CT-VHSG was performed with a 64-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 100 kV – 150 mAs – 3.16 s scan time • Effective radiation dose: 0.9 mSv. Images

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Normal Radiologic Anatomy of Female Reproductive System

Findings and Interpretation Conventional hysterosalpingography, frontal spot (Fig. A) shows a normal cervical canal, a right lateralized uterine cavity of regular size and shape and normal morphology of both fallopian tubes (arrows). After a cesarean delivery three years ago, CT-VHSG was performed for evaluation the cause of secondary infertility of 18 months duration. Coronal maxi-

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mum intensity projection (Fig. B) and volume rendering image with bone sculpting, frontal (Fig. C) and left oblique (Fig. D) views display an endometrial cavity of normal size and shape, with a small cesarean section scar (arrows). Both fallopian tubes are patent (arrowheads), with spillage of contrast material in the peritoneal cavity (asterisks) and positive Cottè test. Virtual endoscopy view (Fig. E) and conventional hysteroscopy (Fig. F) display a normal endometrial cavity.

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Case 6 C. Capuñay, P. Carrascosa, M. Baronio Normal Anatomy Clinical History • Twenty-five-years-old female with primary infertility of 12 months duration. • No relevant past medical or surgical history. • Previous exams: normal transvaginal ultrasound as the initial imaging method in the fertility work-up.

• CT-VHSG indication: further evaluation to determine the cause of infertility and to rule out pathology. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time • Effective radiation dose: 0.3 mSv. Images

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B

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D

E

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G

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Normal Radiologic Anatomy of Female Reproductive System

Findings and Interpretation CT-VHSG maximum intensity projections at different views (Figs. A, B and C) display a uterine cavity of normal size and shape, with patent fallopian tubes (arrows) and the presence of contrast material in the peritoneal cavity (asterisks) with positive Cottè test. Volume rendering image, lateral view without bone sculpting (Fig. D) and volume

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rendering images with bone sculpting, frontal (Fig. E), right oblique (Fig. F) and superior (Fig. G) views display an anteverted uterus with normal cervix, endometrial cavity and fallopian tubes (arrows). There is bilateral spillage of contrast into the peritoneal cavity with positive Cottè test (asterisks). Virtual endoscopy view (Fig. H) and conventional hysteroscopy (Fig. I) demonstrate a normal endometrial cavity.

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– 80 kV – 100 mAs – 1.3 s scan time • Effective radiation dose: 0.3 mSv.

Case 7 C. Capuñay, P. Carrascosa Normal Anatomy

Images

Clinical History • Thirty-two-years-old female with primary infertility of 12 months duration. • No relevant past medical or surgical history. • CT-VHSG indication: initial imaging method in the fertility work-up. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval

Findings and Interpretation CT-VHSG maximum intensity projections (Figs. A, B and C) display a uterine cavity of normal size and shape and patent fallopian tubes (arrows). There is presence of contrast material in the peritoneal cavity (asterisks) with positive Cottè test. Volume rendering image, frontal view (Fig. D) reveal a normal cervix, uterine cavity and fallopian tubes (arrows) and spillage of contrast into the peritoneal cavity (asterisk). Virtual endoscopy views (Figs. E and F) demonstrate a normal endometrial cavity.

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Normal Radiologic Anatomy of Female Reproductive System

Case 8 P. Carrascosa, C. Capuñay Normal Anatomy Clinical History • Thirty-eight-years-old female with primary infertility of 18 months duration. • No relevant past medical or surgical history. • Previous exams: normal transvaginal ultrasound as the initial imaging method in the fertility work-up.

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• CT-VHSG indication: further evaluation to determine the cause of infertility. • CT-VHSG was performed with a 64-slice CT scanner. • CT technical parameters: – 0.9 mm slice thickness – 0.45 mm reconstruction interval – 100 kV – 150 mAs – 3.16 s scan time • Effective radiation dose: 0.9 mSv. Images

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Findings and Interpretation CT-VHSG sagittal thick slab multiplanar reconstruction (Fig. A), sagittal (Fig. B) and coronal (Fig. C) maximum intensity projections display an anteverted uterus, with endometrial cavity of normal size and shape and patent fallopian tubes (arrows). There is presence of contrast material in the peritoneal cavity (asterisks) with positive

P. Carrascosa and C. Capuñay

Cottè test. Volume rendering image, lateral (Fig. D) and frontal (Fig. E) views without bone sculpting and frontal view with bone sculpting (Fig. F) reveal an anteverted uterus with normal cervix, uterine cavity and fallopian tubes (arrows) and bilateral spillage of contrast into the peritoneal cavity (asterisks). Virtual endoscopy views display a normal cervical canal (Fig. G) and endometrial cavity (Figs. H and I).

Normal Radiologic Anatomy of Female Reproductive System

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– 4 s scan time • Effective radiation dose: 0.5 mSv.

Case 9 C. Capuñay, J. Carpio, L. Sarati

Images

Retroversio-retroflexio Uterus

Findings and Interpretation

Clinical History • Forty two years-old female with primary infertility of 15 months duration. • No relevant past medical or surgical history. • CT-VHSG indication: evaluation of the reproductive system as the first line diagnostic imaging test in the infertility work-up. • CT-VHSG was performed with 128-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 100 kV – 100 mAs

Mid-sagittal transvaginal ultrasound image (Fig. A) shows an acutely retroverted uterus with normal endometrium in the luteal phase. CT-VHSG demonstrates a normal female reproductive system. Sagittal (Fig. B) and axial (Fig. C) maximum intensity projections show a right lateralized uterus in the pelvis. The body of the uterus is bent backward over the cervix (arrows) and the cervix bent backward over the vagina (arrowhead). These findings correspond to a uterus in retroversio-retroflexio position. Coronal maximum intensity projection (Fig. D) displays a uterine cavity with regular contours and normal fallopian tubes (arrows). Virtual endoscopy views demonstrate a normal cervical canal (Fig. E) and endometrial cavity (Fig. F).

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– 1.3 s scan time • Effective radiation dose: 0.3 mSv.

Case 10 C. Capuñay, J. Carpio, L. Sarati

Images

Anteversio-retroflexio Uterus

Findings and Interpretation

Clinical History • Thirty-three years-old female with primary infertility of 16 months duration. • No relevant past medical or surgical history. • CT-VHSG indication: evaluation of the reproductive system as the first line diagnostic imaging test in the infertility work-up. • CT-VHSG was performed with 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs

CT-VHSG demonstrates a normal female reproductive system. Sagittal (Fig. A) maximum intensity projection reveals the body of the uterus bent backward over the cervix (arrow) and the cervix bent forward over the vagina (arrowhead). These findings correspond to a uterus in anteversioretroflexio position. Coronal maximum intensity projection (Fig. B) and volume rendering image, frontal view (Fig. C) show a right lateralized uterine cavity and patent fallopian tubes (arrows), with normal spillage of contrast into the peritoneal cavity with positive Cottè test (asterisks). Virtual endoscopy views reveal a normal cervical canal (Fig. D) and endometrial cavity (Figs. E and F).

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Normal Radiologic Anatomy of Female Reproductive System

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– 4 s scan time • Effective radiation dose: 0.5 mSv.

Case 11 J. Carpio, L. Sarati, C. Capuñay

Images

Retroversio-anteflexio Uterus

Findings and Interpretation

Clinical History • Forty two years-old female with primary infertility of 11 months duration. • No relevant past medical or surgical history. • CT-VHSG indication: evaluation of the reproductive system as the first line diagnostic imaging test in the infertility work-up. • VHSG was performed with 128-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 100 kV – 100 mAs

CT-VHSG demonstrates a normal female reproductive system. Sagittal (Fig. A) maximum intensity projection reveals the body of the uterus bent forward over the cervix (arrow) and the cervix bent backward over the vagina (arrowhead). These findings correspond to a uterus in retroversioanteflexio position. Coronal (Fig. B) and oblique (Figs. C and D) maximum intensity projections show a right lateralized uterine cavity, normal fallopian tubes (arrows) and free spill of contrast into the peritoneal cavity (asterisks). Volume rendering image (Fig. E) and virtual endoscopy view (Fig. F) demonstrate a normal endometrial cavity with regular walls.

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P. Carrascosa and C. Capuñay

Case 12 J. Carpio, L. Sarati, C. Capuñay Intrauterine Device Clinical History • Thirty-four-years-old female with secondary infertility. • Obstetric history: G4A4. History of recurrent pregnancy loss, the last one 15 months ago required surgical treatment (curettage). • No other relevant past medical or surgical history.

• CT-VHSG indication: location of intrauterine device and evaluation of uterine cavity. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time • Effective radiation dose: 0.3 mSv. Images

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Normal Radiologic Anatomy of Female Reproductive System

Findings and Interpretation CT-VHSG coronal multiplanar reconstruction (Fig. A), sagittal (Fig. B) and axial (Fig. C) thick slab maximum intensity projections show a left lateralized uterus with the presence of a proper inserted intrauterine device (IUD) in the middle of the endometrial cavity (arrows). Both patent

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normal fallopian tubes are visible (arrowheads). Coronal maximum intensity projection (Fig. D) and volume rendering image, posterior view (Fig. E) demonstrate the IUD in the correct position within the uterine cavity, as well as both fallopian tubes (arrowheads) with bilateral normal spillage of contrast in the peritoneal cavity (asterisk). Virtual endoscopy view (Fig. F) shows a normal endometrial cavity.

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Case 13 P. Carrascosa, C. Capuñay

•

Cervical Balloon Cannula

• •

Clinical History • Thirty-six-years-old female with primary infertility of 18 months duration. • No other relevant past medical or surgical history. • Previous exams: conventional hysterosalpingography performed as the first line diagnostic imaging test in the infertility work-up showed alteration in the normal

•

uterine morphology. Fallopian tubes were not visualized during the procedure. CT-VHSG indication: further evaluation of uterine cavity. CT-VHSG was performed with a 64-slice CT scanner. CT technical parameters: – 0.9 mm slice thickness – 0.45 mm reconstruction interval – 100 kV – 150 mAs – 3.16 s scan time Effective radiation dose: 0.9 mSv.

Images

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Findings and Interpretation Conventional hysterosalpingography frontal and oblique views (Figs. A, B, C and D) reveal a triangular uterine cavity with marked angulation and irregular margins (asterisks); the fallopian tubes are not visible. CT-VHSG was performed using a balloon catheter due to important reflux of contrast during the procedure. Axial (Fig. E) and sagittal (Fig. F) thick slab multiplanar reconstructions with soft tissue window show a retroverted uterus and the presence of a round, air-density image in the lower segment of the uterus, corresponding to the balloon of the catheter (arrows). Both fallopian tubes are patent

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L

(arrowheads). Axial (Fig. G) and sagittal (Fig. H) maximum intensity projections display similar imaging findings than the multiplanar reconstructions, showing a focal filling defect on the lower segment of the uterine cavity, corresponding to the catheter balloon (arrows). Both fallopian tubes are visible (arrowheads), with spillage of contrast into the peritoneal cavity, with positive Cottè test (asterisks). Volume rendering images, lateral (Fig. I) and superior (Fig. J) views demonstrate the retroverted uterus with a uterine cavity of normal shape and regular contours. Fallopian tubes are visible (arrows). Virtual endoscopy views (Figs. K and L) show a normal endometrial cavity.

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Case 14 P. Carrascosa, C. Capuñay, M. Baronio Normal Anatomy Clinical History • Thirty-years-old female with primary infertility of 24 months duration. • No relevant past medical or surgical history. • Previous exams: normal transvaginal ultrasound.

• CT-VHSG indication: evaluation of the reproductive system as the first line diagnostic imaging test in the infertility work-up. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 100 kV – 100 mAs – 1.3 s scan time • Effective radiation dose: 0.5 mSv. Images

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Normal Radiologic Anatomy of Female Reproductive System

Findings and Interpretation CT-VHSG sagittal multiplanar reconstruction with soft tissue window (Fig. A) reveals an anteversio-anteflexio uterus with normal size and shape. The myometrium is clearly visualized using this window settings. Coronal multiplanar reconstruction (Fig. B), maximum intensity projections in positive (Fig. C) and negative (Fig. D) windows and volume

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rendering image, frontal view (Fig. E) show a normal cervix, uterine cavity (white asterisks) and fallopian tubes (arrows) and bilateral spillage of contrast into the peritoneal cavity with positive Cottè test (black asterisks). Virtual endoscopy views (Figs. F, G and H) display a normal endometrial cavity, fundus and uterine horns. Conventional hysteroscopy correlation (Fig. I) shows the uterine fundus and both cornus.

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Case 15 P. Carrascosa, M. Baronio, C. Capuñay Normal Anatomy Clinical History • Thirty-three-years-old female with primary infertility of 3 months duration. • No relevant past medical or surgical history.

• CT-VHSG indication: evaluation of the reproductive system as the first line diagnostic imaging test in the infertility work-up. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time • Effective radiation dose: 0.3 mSv. Images

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Normal Radiologic Anatomy of Female Reproductive System

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Findings and Interpretation CT-VHSG maximum intensity projections (Figs. A, B and C) and volume rendering images (Figs. D, E and F) in different views show a normal cervix, uterus and fallopian tubes (arrows), with bilateral spillage of contrast into the

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peritoneal cavity (positive Cottè test). Virtual endoscopy views of the cervical canal (Fig. G) and uterine cavity (Fig. H) display normal anatomy. Conventional hysteroscopy (Figs. I and L) and focalized virtual endoscopy (Figs. J and K) views display the right and left fallopian tube ostia.

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Case 16 L. Sarati, J. Carpio, C. Capuñay Normal Anatomy Clinical History • Thirty-nine-years-old female with primary infertility of 14 months duration. • No relevant past medical or surgical history. • Current method of contraception: none.

• CT-VHSG indication: evaluation of the reproductive system as the first line diagnostic imaging test in the infertility work-up. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time • Effective radiation dose: 0.3 mSv. Images

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Normal Radiologic Anatomy of Female Reproductive System

Findings and Interpretation Transvaginal mid-sagittal ultrasounds (Figs. A and B) show the endometrium in its long axis measures 12 mm (calipers) with an accentuated trilaminar pattern during the late proliferative phase (arrows). Conventional hysterosalpingography frontal view (Fig. C) reveals a normal uterine cavity lateralized to the left and two normal fallopian tubes (arrows) with normal spillage of contrast into the peritoneal cavity, positive Cottè test (asterisks). CT-VHSG demonstrates a

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normal female reproductive system. Coronal maximum intensity projections (Figs. D and E) display similar imaging findings than the X-ray exam, showing a left lateralized uterine cavity, normal fallopian tubes (arrows) and free spill of contrast into the peritoneal cavity (asterisks). Sagittal maximum intensity projection (Fig. F) reveals the uterus in anteversoflexion position. Volume rendering image (Fig. G) demonstrates the inverted triangular shape of the normal uterine cavity with regular contours. Virtual endoscopy views (Figs. H and I) show a normal endometrial cavity.

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Case 17 C. Capuñay, P. Carrascosa, J. Carpio Cornual Lucencies Clinical History • Twenty-seven-years-old female with primary infertility of 36 months duration. • No relevant past medical or surgical history. • Previous exams: normal transvaginal ultrasound as the initial imaging method in the fertility work-up.

• CT-VHSG indication: further evaluation of the reproductive system. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time • Effective radiation dose: 0.3 mSv. Images

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Findings and Interpretation

References

CT-VHSG axial (Fig. A) and coronal (Fig. B) maximum intensity projections display a normal cervical canal and uterine cavity. There are focal, linear hypodensities in both uterine horns, adjacent to each fallopian tube ostium, representing a normal anatomic variant known as cornual lucencies (arrows). Oblique maximum intensity projections (Figs. C and D) and volume rendering image, frontal view (Fig. E) show a normal cervical canal and uterine cavity, the linear hypodensities in both uterine horns (arrows) as well as normal fallopian tubes (arrowheads), with spillage of contrast into the peritoneal cavity with positive Cottè test (asterisks). Virtual endoscopy view (Fig. F) demonstrates a normal endoluminal view of the endometrial cavity and uterine horns.

1. Gossman W, Fagan SE, Sosa-Stanley JN, Peterson DC. Anatomy, Abdomen and Pelvis, Uterus. PMID: 29262069. 2. Rohen JW. Topographische Anatomie. Stuttgart: Schattaer; 1999. 3. Carrascosa PM, Capuñay C, Vallejos J, et al. Virtual hysterosalpingography: a new multidetector CT technique for evaluating the female reproductive system. Radiographics. 2010;30:643–61. 4. Shulman LP. Müllerian anomalies. Clin Obstet Gynecol. 2008;51:214–22. 5. Lin PC, Bhatnagar KP, Nettleton GS, et al. Female genital anomalies affecting reproduction. Fertil Steril. 2002;78:899–915. 6. Toaff ME, Lev-Toaff AS, Toaff R. Communicating uteri: review and classification with introduction of two previously unreported types. Fertil Steril. 1984;41:661–79. 7. Troiano RN, McCarthy SM. Müllerian duct anomalies: imaging and clinical issues. Radiology. 2004;233:19–34. 8. Ubeda B, Paraira M, Alert E, et al. Hysterosalpingography: spectrum of normal variants and nonpathological findings. AJR Am J Roentgenol. 2001;177(1):131–5. 9. Hysterosalpingography: a text and atlas. 2nd ed. Baltimore, MD: Williams & Wilkins; 1998. p. 29–30.

Evaluation of the Cervix Patricia Carrascosa and Carlos Capuñay

Pathology of the Cervix Most of the cervical abnormalities found in CT-VHSG exams constitute benign pathologies. Malignant neoplasms of the uterine cervix can be identified by CT-VHSG in advanced stages, but this modality does not have a role in staging, treatment planning, and follow-up of cervical malignancies.

Cervix Stenosis Cervical canal diameter is variable between women, and in a subgroup of patients, the canal may be narrow, as an anatomical variant. Most common causes of pathological cervical stenosis include cervical trauma secondary to surgical procedures such as loop electrosurgical excision procedures, cone biopsy or uterine curettage, and chronic infection (chronic cervicitis). The lumen narrowing can be focal (less than 10 mm long) or diffuse, and constitute a troublesome clinical problem in infertile patients, particularly those requiring insemination treatments. Using curve multiplanar reconstructions (MPR), the cervical wall and lumen are clearly and easily viewed and fully appreciated on CT-VHSG images, especially since a balloon catheter or any other endoluminal device is not used [1, 2]. The maximum intensity projection (MIP) and volume P. Carrascosa (&) Medical Director and Research Department, Diagnóstico MaipúDASA, Av. Maipú 1668, Vicente López, Buenos Aires, B1602ABQ, Argentina e-mail: [email protected] C. Capuñay Computed Tomography & Magnetic Resonance Imaging Department and Research Department, Diagnóstico MaipúDASA, Av. Maipú 1668, Vicente López, Buenos Aires, B1602ABQ, Argentina e-mail: [email protected]

rendering (VR) images also facilitates the detection of cervical stenosis. Virtual endoscopy complements the evaluation, with proximal and distal stenosis endoluminal navigation [3, 4].

Synechiae Cervical synechiae are scar fibrous tissue bands within the cervical canal that connect opposite cervical walls and generate the partial or total obliteration of the lumen. On CT-VHSG exams, cervical adhesions are identified as irregular, lineal endoluminal filling defects in the cervical canal of soft tissue density extending from the cervical wall to the lumen or to the opposite wall, reducing its diameter [5–7]. Focal or diffuse synechiae extension can be evaluated throughout the different reconstructions.

Hypertrophic Cervical Folds Prominent enlarged folds are normal findings, but also can represent incipient pathology. They are represented by longitudinal elevated soft tissue images on the cervical canal walls, projecting into the lumen on coronal and sagittal MPRs and virtual endoscopy images. In the volume rendering three-dimensional images, they are seen as depressions of longitudinal arrangement at the level of the cervix [8–11].

Polyps Cervical polyps are focal growths of the endocervical mucosa protruding to the cervical canal. The vast majority of cervical polyps are benign lesions incidentally discovered during routine pelvic exams, but in a low percentage of cases

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can become malignant. For this reason, they must be analyzed. The etiology of cervical polyps is uncertain; however, it is strongly associated with an increase in estrogen levels and inflammation of the uterine neck. They can be single or multiple, and they can range in size from a few millimeters to several centimeters long, with fingerlike or bulb shapes. They are typically asymptomatic, but on occasions they can cause irregular heavy menstrual bleeding, bleeding after intercourse or between periods. CT-VHSG accurate identify polyps as soft tissue lesions of variable size and homogeneous attenuation that bulges into the mucosa, projecting to the cervical lumen. They do not contain trapped gas, as air bubbles may pass by performing contrast injection and simulate elevated lesions that can be confused with a polyp if only virtual endoscopy images are evaluated [10–12]. Based on the high spatial resolution of the CT images, very tiny lesions of less than 2 mm can be identified on axial and MPR images. According to its size, the canal lumen is partially or totally obliterated. This imaging finding is appreciated as a focal filling defect along the cervix in the volume rendering three-dimensional images and as a protruding smooth contours lesion projecting into the lumen on virtual endoscopy.

Diverticles Diverticles are abnormal herniations or sac opening from the cervical wall that can be found on CT-VHSG exams, and they do not represent an important diagnostic finding. On axial and MPR images, as well as on volume rendering images, they are seen as an outpouching of contrast (stick-out lesions) along the neck of the uterus. The diverticular orifice is visible on virtual endoscopy images [8, 9].

Cervical Cancer Cervical cancer is a gynecological cancer most frequent in women under 50 years of age. Its incidence has been reduced by 75% due to the development of cytological screening programs [13, 14]. The principal cause of cervical cancer is the infection of the epithelium by the Human Papilloma Virus. Precancerous stages include the cervical intraepithelial neoplasia (CIN) or a scaly intraepithelial lesion (SIL) which progresses to an in situ carcinoma and then to an invasive cancer [15].

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The prognosis of uterine neck cancer is related to the tumor size, the extension of the myocervical invasion, the parametrium invasion, the extension to the pelvic wall, the affectation of the lymph nodes, and the presence of distant metastases. All those parameters must be evaluated and included in the imaging reports. Magnetic resonance imaging allows the visualization of the tumor in early stages, and simultaneously, determine the compromise of the adjacent structures, permitting the pre-operative staging [16–18]. CT-VHSG does not have a predominant role in the diagnosis of this tumor. Incidental findings can be seen in CT-VHSG studies performed for other reasons. According to the tumor stage, a soft tissue density lesion at the level of the cervical wall partially or completely obliterating the canal can be seen.

Uterine Cervical Evaluation in Infertile Patients with Embryo Transfer Treatments The embryo transfer is the final procedure of the in vitro fertilization process that involves a technique where one or more embryos are deposited into the uterine cavity for their latter implantation and development. Typically it is carried out by using a fine catheter inserted through the vagina across the uterine cervix up to the uterine cavity [19]. The cervical transfer test, routinely performed prior to the embryo transfer procedure, consists of passing a transfer catheter through the cervical canal up to the upper third part of the uterine cavity. It permits knowing the characteristics of the cervical canal and usually is carried out via ultrasound to visualize the location where to place the embryos. Performing this preliminary test can prevent a traumatic transfer that is associated with low rates of implantation and pregnancy and an increase in ectopic implants. CT-VHSG exams constitute an excellent noninvasive diagnostic alternative for the evaluation of the neck and cervical canal anatomy. Sagittal MPR allows the determination of the cervical-uterine angle between the lower uterine segment and the cervical canal, the measurement of caliber and length of the cervical canal, as well as the identification of pathologies that can cause partial or total obstruction of the cervical lumen, fundamental to determine the feasibility and success of embryo transfer treatments (Fig. 1). In our institution, we conducted a prospective comparison study between the cervical catheter test and the CT-VHSG evaluation of the cervix. The study was performed on 100 patients with a history of infertility prior to the embryo

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Fig. 1 Different examples of cervical-uterine angles. The angle size varies according to the urinary bladder distension (asterisks) and the anatomy of the uterus. Normal cervical-uterine angles with full urinary bladder distension (A, B, C). Reduced cervical-uterine angles due to poor urinary bladder distension (D, E). Reduced cervical-uterine angle

due to the anatomy of the uterus, accentuated by a poor urinary bladder distension (F). Slightly reduced cervical-uterine angle due to the anatomy of the uterus. In this case the urinary bladder distension does not influence the angle measurement (G). Reduced cervical-uterine angle due to the retroflexio position of the uterus (H, I)

transfer. On the day of the exam, prior to the CT- VHSG, a gynecologist performs the cervical canal test with a Wallace catheter. CT-VHSG images were analyzed by a radiologist. Interpretation of the imaging includes the assessment of permeability of the uterine canal via the passing of contrast to the endometrial cavity, its caliber and length, the cervical-uterine angle, the position of the uterus, and the presence of anatomical variants or cervical pathologies. All this information is of the utmost importance in this group of infertile patients [20]. A good correlation between both methods, calculated via the Cohen’s kappa coefficient, was observed (k = 0.92) in the evaluation of the permeability of the uterine neck. An advantage of CT-VHSG is that it also provides useful

anatomical information for identifying the probable cause for the failure of the embryo transfer. In 65% of the patients, the cervical test was nontraumatic (normal). Within this group, the CT-VHSG demonstrated a normal cervical canal in 92% of the women, with an average cervical-uterine angle of 132° and a cervical-uterine angle over 90° in 95% of the patients. The CT-VHSG exams also showed 3 cervical polyps less than 5 mm and 2 patients with cervical synechiae that did not produce cervical luminal stenosis. In the rest of the patients (35%), the cervical test was abnormal. In this group, CT-VHSG showed 5 cervical polyps greater than 5 mm, 6 cervical synechiae and 3 sinuous cervical canal. The average cervical-uterine angle was 76°.

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Case 18 P. Carrascosa, C. Capuñay Focal Cervical Stenosis Clinical History • Twenty-six-year-old female with primary infertility of 14 months duration. • No relevant past medical or surgical history.

• CT-VHSG indication: evaluation of the reproductive system as the first line diagnostic imaging test in the infertility work-up. • CT-VHSG was performed with a 64-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 100 kV – 150 mAs – 3.16 s scan time. • Effective radiation dose: 0.9 mSv. Images

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Findings and Interpretation CT-VHSG sagittal (Fig. A) and coronal (Figs. B and C) maximum intensity projections and volume rendering images, lateral (Fig. D) and frontal (Figs. E and F) views show an anteverted uterus with a focal narrowing in the proximal segment of the cervical canal (arrows). The uterine cavity has

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smooth contours with a small indentation at the fundus, configuring an arcuate uterus. Both fallopian tubes are patent (arrowheads) with normal spillage of contrast into the peritoneal cavity (asterisks). Virtual endoscopy views show a normal distal cervical canal (Fig. G) with a focal stenosis (arrow) in the distal segment (Fig. H) and a normal endometrial cavity (Fig. I).

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Case 19 P. Carrascosa, C. Capuñay Focal Cervical Stenosis Clinical History • Twenty-eight-year-old female with primary infertility of 18 months duration. • CT-VHSG indication: determination of the cause of infertility. • No relevant past medical or surgical history.

• CT-VHSG was performed with a 64-slice CT scanner. • CT technical parameters: – 0.9 mm slice thickness – 0.45 mm reconstruction interval – 100 kV – 150 mAs – 3.16 s scan time – Two CT acquisitions in the same imaging session were performed. • Effective radiation dose: 1.8 mSv. Images

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Evaluation of the Cervix

Findings and Interpretation CT-VHSG sagittal maximum intensity projection (Fig. A) shows an anteverted uterus with a focal narrowing in the proximal segment of the cervical canal (arrow). Coronal maximum intensity projections with different angles (Figs. B and C) demonstrate a uterine cavity of normal size and shape and the focal narrowing of the cervical canal (arrows). Both fallopian tubes are patent (arrowheads) with normal spillage of contrast into the peritoneal cavity (asterisks). Volume rendering images, lateral view (Fig. D) and frontal views (Figs. E and F) with different windowing

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and transparency settings demonstrate the focal cervical stenosis (arrows) as well as hyperplasic folds on the anterior wall of the endometrial cavity (arrowhead). Thin slab coronal volume rendering image (Fig. G) reveals the cervical stenosis as well as a small elevated lesion projecting into the uterine cavity, compatible to a small endometrial polyp (arrow). Virtual endoscopy view (Fig. H) shows the reduced lumen of the cervical canal at the site of the focal cervical stenosis (arrow). The virtual endoluminal view of the uterine cavity (Fig. I) displays the small endometrial polyp (asterisk) and the hyperplasic folds on the anterior wall (arrows).

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Case 20 P. Carrascosa, C. Capuñay Focal Cervical Stenosis Clinical History • Thirty-nine-year-old female with secondary infertility of 36 months duration. • Obstetric history: G1P1. • No relevant past medical or surgical history. • Previous exams: normal transvaginal ultrasound.

• CT-VHSG indication: determination of the cause of infertility. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time. • Effective radiation dose: 0.3 mSv. Images

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Findings and Interpretation CT-VHSG maximum intensity projections showing pelvic bones (Fig. A) and after bone removal with volume sculpting (Fig. B) show a focal stenosis in the distal cervix (arrows). The uterine cavity is normal. The right fallopian tube presents normal morphology while the left fallopian tube is dilated (arrowheads). Bilateral spillage of contrast in the peritoneal cavity with positive Cottè test (asterisks). Volume rendering

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images in different views (Figs. C and D) demonstrate the focal cervical stenosis (white arrows) as well as a focal hyperplasic fold adjacent to the right cornual ostium (yellow arrow). Dilatation of the left fallopian tube is also appreciated (arrowheads). Virtual endoscopy views (Figs. E and F) at the level of the focal cervical stenosis (arrow in Fig. E) and in the area of the hyperplasic fold (arrows in Fig. F) on the right uterine horn.

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Case 21

• Effective radiation dose: 1 mSv.

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Images

Cervical Stenosis in Arcuate Uterus

Findings and Interpretation

Clinical History

CT-VHSG axial image (Fig. A) shows a focal elevated lesion at the fundus of the uterine cavity (arrow) compatible with a small endometrial polyp. Volume rendering images, frontal views (Figs. B and C) illustrate an arcuate uterus with a focal cervical canal stenosis (white arrows) and the round filling defect in the fundus of the uterine cavity (yellow arrows). Both fallopian tubes are patent (arrowheads) with spillage of contrast into the peritoenal cavity (asterisk). Virtual endoscopy view (Fig. D) shows the severe reduction of the cervical canal lumen at the level of the stenosis (arrow). The endoluminal views of the endometrial cavity (Figs. E and F) reveal the elevated lesion at the uterine fundus (asterisks) and the uterine horns.

• Thirty-one-year-old female with primary infertility of 16 months. • No relevant past medical or surgical history. • CT-VHSG indication: evaluation the cause of infertility as the initial imaging method in the fertility work-up. • CT-VHSG was performed with a 64-slice CT scanner. • CT technical parameters: – 0.9 mm slice thickness – 0.45 mm reconstruction interval – 120 kV – 150 mAs – 3.16 s scan time.

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Case 22 P. Carrascosa, C. Capuñay Uterine Cervix Stenosis Clinical History • Thirty-eight-year-old female with primary infertility of 20 months. • Previous exams: transvaginal ultrasound as the initial imaging method in the fertility work-up.

• CT-VHSG indication: further evaluation of the reproductive system. • CT-VHSG was performed with a 64-slice CT scanner. • CT technical parameters: – 0.9 mm slice thickness – 0.45 mm reconstruction interval – 100 kV – 150 mAs – 3.16 s scan time. • Effective radiation dose: 0.9 mSv. Images

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Findings and Interpretation Sagittal multiplanar reconstruction (Fig. A), maximum intensity projection (Fig. B) and volume rendering image, lateral view (Fig. C) illustrate a retroversio-anteflexio uterus and the presence of cervical stenosis (arrows). Coronal maximum intensity projection (Fig. D) and volume rendering

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image, frontal view (Fig. E) display a left lateralized uterine cavity with normal size and shape, and the stenosis of the cervical canal (arrows). Virtual endoscopy view at the level of the cervix (Fig. F) shows a severe reduction of the cervical canal lumen (arrow). The endoluminal view of the endometrial cavity (Fig. G) and of the right (Fig. H) and left (Fig. I) uterine horns demonstrate the absence of pathology.

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– 3.16 s scan time. • Effective radiation dose: 0.5 mSv.

Case 23 P. Carrascosa, C. Capuñay

Images Uterine Cervix Stenosis Findings and Interpretation Clinical History • Twenty-five-year-old female with primary infertility of 12 months. • Previous exams: transvaginal ultrasound as the initial imaging method in the fertility work-up. • CT-VHSG indication: evaluation the cause of infertility. • CT-VHSG was performed with a 64-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 150 mAs

Sagittal transvaginal ultrasound image (Fig. A) shows a longitudinal view of the uterus with normal morphology and endometrial thickness. CT-VHSG sagittal (Fig. B) and coronal (Fig. C) maximum intensity projections and volume rendering image, frontal view (Fig. D) illustrate an anteversio-anteflexio uterus with a diffusely thin cervical canal (arrows). The uterine cavity as well as both fallopian tubes are normal (arrowheads). Virtual endoscopy view of the cervix (Fig. E) shows a severe reduction of the cervical canal lumen at the level of the stenosis (arrow). The endoluminal view of the endometrial cavity is normal (Fig. F).

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Case 24 P. Carrascosa, C. Capuñay Uterine Cervix Stenosis Clinical History • Twenty-eight-year-old female with secondary infertility of 30 months. • Obstetric history: G2P1A1. • Past medical history of oral contraceptive pills for contraception during 11 months.

• Previous exams: conventional hysterosalpingography performed 8 months ago as the initial imaging method in the fertility work-up. • CT-VHSG indication: to confirm the diagnosis of the conventional hysterosalpingography. • CT-VHSG was performed with a 64-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 150 mAs – 3.16 s scan time. • Effective radiation dose: 0.5 mSv. Images

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Evaluation of the Cervix

Findings and Interpretation Conventional hysterosalpingography (Fig. A) reveals diffuse stenosis of the cervical canal (arrow). The uterine cavity (asterisk) and fallopian tubes (arrowheads) were normal. CT-VHSG maximum intensity projections in sagittal (Fig. B) coronal (Fig. C) and left oblique (Fig. D) views show a retroversio-retroflexio uterus with narrowing of the endocervical canal (arrows) and normal endometrial cavity

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(asterisks). The right fallopian tube is nicely illustrated (arrowhead) with and adequate passage of contrast to the peritoneal cavity (positive Cottè test). Sagittal (Fig. E) and coronal (Fig. F) volume rendering images show the narrowing of the endocervical canal (arrows) as well as the uterine position within the pelvis. Virtual endoscopy views at the level of the proximal and distal cervical canal (Figs. G and H) display the luminal stenosis of the cervical canal (arrows). The uterine cavity is normal (Fig. I).

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Focal Cervical Synechiae

– 0.315 mm reconstruction interval – 100 kV – 100 mAs – 4 s scan time. • Effective radiation dose: 0.5 mSv.

Clinical History

Images

• Thirty-seven-year-old female with secondary infertility of 25 months duration. • Obstetric history: G1A1. History of first-trimester spontaneous abortion that required surgical treatment (dilation and curettage). Three unsuccessful in vitro fertilization procedures in the last 14 months. • No other relevant past medical or surgical history. • Previous exams: normal transvaginal ultrasound. • CT-VHSG indication: further evaluation of the reproductive system. • CT-VHSG was performed with a 128-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness

Findings and Interpretation

Case 25 P. Carrascosa, M. Baronio, C. Capuñay

CT-VHSG axial CT image (Fig. A) and coronal multiplanar reconstruction (Fig. B) show a linear filling defect within the lumen of the cervical canal (arrows). Coronal maximum intensity projections with different angles (Figs. C and D) demonstrate the linear endoluminal defect on the left side of the cervical canal (arrows). The uterine cavity has normal size and shape and both fallopian tubes are patent. Virtual endoscopy view (Fig. E) and conventional hysteroscopy correlation (Fig. F) reveal the presence of intrauterine synechiae (asterisks).

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Case 26 J. Carpio, L. Sarati, M. Baronio Cervical Synechiae Clinical History • Thirty-five-year-old female with primary infertility. • Medical history of endometriosis. • Previous exams: magnetic resonance imaging for the assessment of pelvic endometriosis one year ago.

• CT-VHSG indication: evaluation of the reproductive system. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time. • Effective radiation dose: 0.3 mSv. Images

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Findings and Interpretation Coronal (Fig. A), sagittal (Fig. B) and axial (Fig. C) T2-weighted magnetic resonance images show an irregular hypointense lesion within the cervical canal (arrows). There is no evidence of pelvic endometiosis. CT-VHSG curve coronal (Fig. D) and sagittal (Fig. E) multiplanar reconstructions with soft tissue window demonstrate the presence of linear endoluminal defect in the cervical canal, extending from wall to wall (arrows).

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These findings are consistent with the diagnosis of cervical synechiae. Maximum intensity projection (Fig. F) and volume rendering image with localized axial CT image (Fig. G) reveal the wall irregularities and distortion of the cervical canal (arrows). Virtual endoscopy view (Fig. H) shows the endoluminal linear tissue that extends from the anterior wall to the posterior wall of the cervical canal (arrow). Conventional hysteroscopy (Fig. I) demonstrates the cervical synechiae prior its resection (arrow).

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Case 27 L. Sarati, J. Carpio, C. Capuñay Cervical Synechiae Clinical History • Forty-two-year-old female with secondary infertility. • Obstetric history: G1P1, vaginal delivery without medical complications 4 years ago. • Past surgical history: benign right ovarian cyst resection 13 years ago.

• CT-VHSG indication: evaluation the cause of infertility. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time – Two CT acquisitions in the same imaging session were performed. • Effective radiation dose: 0.6 mSv. Images

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Findings and Interpretation CT-VHSG axial image (Fig. A) sagittal multiplanar reconstruction (Fig. B) shows a slanted linear filling defect crossing the lumen at the cevical isthmic region (arrows). This filling defect extends from wall to wall and it is consistent with the diagnosis of synechiae. Coronal maximum

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intensity projection without (Fig. C) and with (Fig. D) surrounding tissue sculpting display and volume rendering image (Fig. E) display the linear filling defect (arrows). Normal anatomy of the rest of the uterine cavity and both fallopian tube is visible. Virtual endoscopy view (Fig. F) shows the endoluminal linear tissue band that extends from wall to wall of the cervical canal (asterisk).

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Case 28 J. Carpio, L. Sarati, C. Capuñay Cervical Synechiae Clinical History • Forty-three-year-old female with secondary infertility. • CT-VHSG indication: evaluation the cause of infertility. • Obstetric history: G1A1, first-trimester spontaneous abortion 4 months ago that required surgical treatment (dilation and curettage).

• No relevant past medical or surgical history. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time. • Effective radiation dose: 0.3 mSv. Images

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Findings and Interpretation CT-VHSG axial (Fig. A), curve coronal (Fig. B) and sagittal (Fig. C) multiplanar reconstructions with soft tissue window demonstrate the presence of linear endoluminal defect in the cervical canal, extending from wall to wall (arrows). The proximal cervix is normal. Maximum intensity projection (Fig. D) and volume rendering image (Fig. E) reveal a transverse linear filling in the

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cervical canal, with a filiform pathway of contrast on the left margin (arrows). Virtual endoscopy view shows a normal proximal cervical canal (Fig. F) and the presence of a linear endoluminal lesion that extends from anterior to posterior cervical walls (asterisks), reducing the lumen of the cervical canal (Figs. G and H). These findings are consistent with the diagnosis of cervical synechiae. Virtual endoscopy view (Fig. I) reveals a normal uterine cavity.

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– 80 kV – 100 mAs – 1.3 s scan time. • Effective radiation dose: 0.3 mSv.

Case 29 P. Carrascosa, C. Capuñay, S. Papier Cervical Synechiae

Images Clinical History Findings and Interpretation • Thirty-three-year-old female with primary infertility of 13 months duration. • No relevant past medical or surgical history. • Previous exams: normal transvaginal ultrasound. • CT-VHSG indication: assessment of the cause of infertility. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval

CT-VHSG axial image (Fig. A) and sagittal multiplanar reconstruction (Fig. B) with soft tissue window show a linear filling defect in the left lateral wall of the cervix that extends to the canal lumen (arrows). Maximum intensity projection (Fig. C) and volume rendering image (Fig. D) show the linear defect compatible with a cervical synechiae (arrows). Virtual endoscopy view (Fig. E) and conventional hysteroscopy (Fig. F) reveal the elevated linear tissue that extends from the left lateral inferior wall of the cervix to the central lumen of the cervical canal (arrows).

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Case 30 P. Carrascosa, C. Capuñay Cervical Synechiae Clinical History • Forty-three-year-old female with secondary infertility of 14 months duration. • Obstetric history: G1A1. History of first-trimester spontaneous abortion 2 years ago that required surgical treatment (dilation and curettage).

No other relevant past medical or surgical history. CT-VHSG indication: assessment the cause of infertility. CT-VHSG was performed with a 64-slice CT scanner. CT technical parameters: – 0.9 mm slice thickness – 0.45 mm reconstruction interval – 100 kV – 150 mAs – 3.16 s scan time. • Effective radiation dose: 0.9 mSv.

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Findings and Interpretation CT-VHSG axial (Fig. A), coronal (Fig. B) and sagittal (Fig. C) maximum intensity projections show an irregular, partially obliterated cervical canal, with small diverticle-like sacculations (arrows). The uterus is in anteversio-anteflexio position and the uterine cavity shows a normal size and morphology, with regular margins. Both fallopian tubes are patent (arrowheads), with spillage of

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contrast into the peritoneal cavity (asterisks). Volume rendering images, frontal views with different angles and windowing settings (Figs. D, E and F) display the irregular filling defect and tortous path compatible with the diagnosis of cervical synechiae (arrows). Fallopian tubes show normal morphology (arrowheads), with spillage of contrast into the peritoneal cavity (asterisks). Virtual endoscopy views of the cervix (Figs. G, H and I) reveal the reduced lumen of the cervical canal.

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Case 31 P. Carrascosa, M. Baronio, C. Capuñay Cervical Synechiae Clinical History • Forty-nine-year-old female with secondary infertility of 18 months duration. • Obstetric history: G1A1. History of first-trimester spontaneous abortion 3 years ago that required surgical treatment (curettage). • No relevant past medical or surgical history.

• Previous exams: normal transvaginal ultrasound as the first line diagnostic imaging test in the infertility work-up. • CT-VHSG indication: assessment the cause of infertility. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time. • Effective radiation dose: 0.3 mSv. Images

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Findings and Interpretation CT-VHSG axial image at the level of the cervix (Fig. A) reveals an irregular cervical canal lumen with the presence of a linear, soft tissue band that extends from wall to wall (arrow). Coronal maximum intensity projection (Fig. B) and volume rendering images, frontal views with different angles

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(Figs. C and D) show a focal filling defect within the middle of the cervical canal, partially obliterating the lumen (arrows). The uterine cavity shows a normal size and morphology, with regular margins. Both fallopian tubes are normal (arrowheads). Virtual endoscopy view (Fig. E) and conventional hysteroscopy correlation (Fig. F) show the presence of the cervical synechiae (asterisks).

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– 80 kV – 100 mAs – 1.3 s scan time. • Effective radiation dose: 0.3 mSv.

Case 32 P. Carrascosa, C. Capuñay Hypertrophic Cervical Folds

Images Clinical History Findings and Interpretation • Thirty-eight-year-old female with primary infertility of 12 months duration. • Current method of contraception: none. • No relevant past medical or surgical history. • CT-VHSG indication: evaluation of the reproductive system as the first imaging diagnostic test in the infertility work-up. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval

CT-VHSG axial image with soft tissue window (Fig. A) shows regular longitudinal elevated soft tissue images on the cervical canal wall projecting into the lumen (arrow) corresponding to hypertrophic cervical folds. Maximum intensity projection (Fig. B) and volume rendering images (Figs. C and D) reveal the imprints of thickened cervical folds as longitudinal depressions along the cervix (arrows). Virtual endoscopy views (Figs. E and F) offer endoluminal views of the hypertrophic cervical folds (arrows).

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Case 33 P. Carrascosa, C. Capuñay Cervical Polyp Clinical History • Forty-year-old female with primary infertility of 15 months duration. • Past medical history of endometrial polyps and left hydrosalpinx. • No other relevant surgical history.

• CT-VHSG indication: evaluation of the reproductive system as the first imaging diagnostic test in the infertility work-up. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time. • Effective radiation dose: 0.3 mSv. Images

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Findings and Interpretation CT-VHSG coronal (Fig. A) and axial (Fig. B) multiplanar reconstructions with soft tissue window reveal a focal round elevated lesion arising from the right postero-lateral wall of the cervical canal. It has a broad base and smooth margins, compatible with a cervical polyp (arrows). Prominent cervical folds are visible on the opposite cervical wall (arrowhead). Coronal maximum intensity projection (Fig. C) shows a normal cervical canal and uterine cavity. The cervical elevated

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lesions are not visible in this type of image reconstruction. Both fallopian tubes are present, identifying a left hydrosalpinx (arrow). Volume rendering image, frontal (Fig. D) and posterior (Fig. E) views display the prominent cervical folds (white arrow) and the imprint of the cervical polyp (yellow arrow). The uterine cavity and right fallopian tube are normal. The left hydrosalpinx is visible (arrowheads). Virtual endoscopy view (Fig. F) shows the elevated lesion with regular margins on the right postero-lateral wall of the cervical canal (asterisk) and the thickened cervical folds (arrows).

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Case 34 C. Capuñay, P. Carrascosa

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Cervical Polyp

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Clinical History • Forty-one-year-old female with primary infertility of 16 months duration. • No relevant medical or surgical history. • Previous exams: transvaginal ultrasound as the initial imaging method in the fertility work-up reveals the

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presence of echogenic elliptic lesion within the cervical canal, suggesting the diagnosis of cervical polyp. CT-VHSG indication: further assessment of the uterine cervix lesion. CT-VHSG was performed with a 64-slice CT scanner. CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 100 kV – 150 mAs – 3.16 s scan time. Effective radiation dose: 0.9 mSv.

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Findings and Interpretation Sagittal transvaginal ultrasound image of the uterus (Fig. A) shows a normal endometrial mucosa line. Transverse transvaginal ultrasound image of the cervix (Fig. B) demonstrates an echogenic lesion which focally interrupts the mucosa line (arrow). CT-VHSG axial image (Fig. C) and sagittal multiplanar reconstruction (Fig. D) with soft tissue window reveal an elongated roundish elevated lesion on the anterior wall of the cervical canal (arrows) compatible with a

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cervical polyp. The lesion can be accurately measured using bidimensional images. Virtual endoscopy view (Fig. E) shows the elevated lesion with regular margins on the anterior wall of the cervical canal, projecting into the lumen (asterisk). Coronal maximum intensity projection (Fig. F) volume rendering image, frontal view (Fig. G) and virtual endoscopy views (Fig. H and I) display a normal endometrial cavity. Both patent fallopian tubes are visible (arrows), with normal spillage of contrast into the peritoneal cavity (asterisks).

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Case 35 P. Carrascosa, C. Capuñay, M. Baronio

Images Cervical Polyp Findings and Interpretation Clinical History • Thirty-five-year-old female with primary infertility of 14 months duration. • Previous exams: normal transvaginal ultrasound performed as the first line diagnostic imaging test in the infertility work-up. • CT-VHSG indication: evaluation the cause of infertility. • No relevant past medical or surgical history. • CT-VHSG was performed with a 64-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 100 kV – 100 mAs

CT-VHSG multiplanar reconstruction with soft tissue window (Fig. A) shows a focal filling defect in the cervix lumen compatible with the diagnosis of cervical polyp (arrow). Thick slab coronal multiplanar reconstruction displays the cervical lesion (arrow) as well as the entire normal uterine silhouette. Sagittal oblique maximum intensity projection (Fig. C) and volume rendering image, frontal view (Fig. D) demonstrate the cervical filling defect (arrows). Both fallopian tubes show normal morphology (arrowheads). Virtual endoscopy view (Fig. E) shows the elevated lesion projecting into the cervical canal (asterisk). Conventional hysteroscopy (Fig. F) confirms the diagnosis of cervical polyp (asterisk). The polyp was successfully removed.

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Case 36 P. Carrascosa, M. Baronio, C. Capuñay

Images Cervical Polyp Findings and Interpretation Clinical History • Thirty-eight-year-old female with secondary infertility of 12 months duration. • Obstetric history: G1C1. • No relevant past medical or surgical history. • Previous exams: normal transvaginal ultrasound performed as the first line diagnostic imaging test in the infertility work-up. • CT-VHSG indication: evaluation the cause of infertility. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs

CT-VHSG volume rendering image, frontal view (Fig. A) shows multiple irregular cervical folds and a large filling defect in the proximal portion of the uterine cervix (arrow). The cesarean section scar is also visible (arrowhead). Axial (Fig. B) and coronal (Fig. C) multiplanar reconstructions with soft tissue window reveal a focal round elevated lesion arising from the right lateral wall of the cervical canal. These imaging findings are compatible with a cervical polyp. Virtual endoscopy view (Fig. D) shows the elevated lesion with regular margins projecting into the cervical canal (asterisk). The uterine cavity is normal (Fig. E). Conventional hysteroscopy (Fig. F) confirms the diagnosis of cervical polyp (asterisk). The polyp was successfully removed.

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Case 37 J. Carpio, L. Sarati, C. Capuñay

Images Cervical Polyp Findings and Interpretation Clinical History • Thirty-six-year-old female with primary infertility of 14 months duration. • Intermenstrual bleeding during the last three months. • No relevant surgical history. • CT-VHSG indication: evaluation of the reproductive system. • CT-VHSG was performed with a 128-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 100 kV – 150 mAs

CT-VHSG axial image (Fig. A) and sagittal multiplanar reconstruction (Fig. B) show a pedunculated filling defect of 7 mm attached to the left posterolateral wall of the cervical canal (arrow). Volume rendering image, oblique left lateral view (Fig. C) and posterior view (Fig. D) illustrate the imprint of the elevated lesion on the cervical canal (arrows). Virtual endoscopy at the level of the proximal cervical canal (Fig. E) reveals the elevated lesion projecting into the cervical canal lumen consistent with the diagnosis of cervical polyp (arrow). There is no evidence of endoluminal lesions in the endometrial cavity (Fig. F).

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Case 38 J. Carpio, L. Sarati, M. Baronio Cervical Polyp Clinical History • Thirty-seven-year-old female with primary infertility under hormone replacement therapy. • CT-VHSG indication: evaluation of the reproductive system. • Previous exams: incomplete conventional hysterosalpingography.

• No other relevant medical or surgical history. • CT-VHSG was performed with a 64-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 3.16 s scan time – Three CT acquisitions in the same imaging session were performed due to reflux of contrast during its administration. • Effective radiation dose: 0.8 mSv. Images

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Findings and Interpretation Conventional hysterosalpingography, frontal view during early injection of contrast (Fig. A) reveals a subtle filling defect on the right lateral wall of the cervix (arrow). This imaging finding is hidden when a complete opacification of the cervical canal and uterine cavity is achieved (Fig. B). The fallopian tubes can not be complete evaluated during the radiological exam. CT-VHSG axial image (Fig. C) and sagittal multiplanar reconstruction (Fig. D) show a small elevated lesion on the right wall, projecting into the cervical canal, compatible with the diagnosis of cervical polyp (arrows). In the maximum intensity projections with (Fig. E) and without bone sculpting (Fig. F), this lesion is not visible. A slight focal narrowing is visible at the

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isthmus (arrows). Both fallopian tubes are normal (arrowheads) with normal spillage of contrast into the peritoneal cavity (asterisk). Volume rendering image (Fig. G) reveals the imprint of the cervical polyp (arrow) as well as the focal indentation in the isthmus (arrowhead). Virtual endoscopy views show the cervical polyp (arrow) on the right wall (Fig. H). The endometrial cavity is normal (Fig. I). Conventional hysteroscopy (Fig. J) confirms the cervical polyp (arrow). Additionally, a large soft tissue left adnexal mass (asterisk) is visible on the axial CT images of the pelvis (Fig. K). Postoperative magnetic resonance imaging follow-up after left ovarian cancer surgery (Fig. L) reveals the presence of the endoluminal lesion in the cervical canal (arrow). There is no evidence of signs of residual or recurrent disease.

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Case 39 L. Sarati, J. Carpio, M. Baronio Cervical Gland Dilation Clinical History • Thirty-seven-year-old female with secondary infertility. • Obstetric history: G1A1. • Past medical history of cervical polyp resected four years ago. • Previous exams: transvaginal ultrasound and pelvic magnetic resonance imaging.

• CT-VHSG indication: confirmation of findings of previous exams and further evaluation of the reproductive system. • CT-VHSG was performed with a 128-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 150 mAs – 3.16 s scan time. • Effective radiation dose: 0.5 mSv. Images

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Findings and Interpretation Sagittal transvaginal ultrasound image (Fig. A) illustrates a longitudinal section of the uterine body, showing a rounded hypoechoic image, lateral to the cervical canal (arrow). Sagittal (Fig. B), coronal (Fig. C) and axial (Fig. D) T2-weighted magnetic resonance images show small hyperintense cystic-like image (arrows) compatible with cervical

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glandular dilation. CT-VHSG multiplanar reconstructions in axial (Fig. E) and coronal (Fig. F) planes as well as three-dimensional maximum intensity projection (Fig. G) show the pseudodiverticular image in relation to the left lateral wall of the cervical canal (arrows). Virtual endoscopy view (Fig. H) and conventional hysteroscopy (Fig. I) demonstrate the inner ostium of the glandular dilation communicating with the lumen of the cervical canal (arrows).

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P. Carrascosa, C. Capuñay Cervical Gland Diverticula Clinical History

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• Twenty-seven-year-old female with primary infertility of 10 months duration. • Family history of infertility. • Previous exams: conventional hysterosalpingography performed as the first imaging diagnostic test in the

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infertility work-up informed a tiny dilated cervical gland in the left cervical wall. CT-VHSG indication: to confirm the conventional hysterosalpingography findings and evaluate other potential causes of infertility. CT-VHSG was performed with a 256-slice CT scanner. CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 80 kV – 100 mAs – 1.3 s scan time. Effective radiation dose: 0.3 mSv.

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Findings and Interpretation Conventional hysterosalpingography (Fig. A) shows a glandular dilatation in the left side of the isthmic-cervical region (arrow). The uterus morphology as well as both fallopian tubes (arrowheads) are normal. There is also normal passage of contrast to the peritoneal cavity (asterisk), with positive Cottè test. CT-VHSG coronal maximum intensity projections in grey scale (Fig. B) and color scale (Fig. C) demonstrate the glandular dilatation (arrows) and the normal uterine cavity. In

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these views, the cervix can also be evaluated showing normal morphology. Maximum intensity projection is an excellent type of image reconstruction to visualize the fallopian tubes. The right fallopian tube is visible unfolded, with exquisite anatomic detail (arrowheads). Volume rendering image (Fig. D) illustrates the tiny glandular dilatation (arrow). In this view, both fallopian tubes are well shown in all their length (arrowheads) as well as positive Cottè test (asterisks). Virtual endoscopy views (Figs. E and F) show the diverticular neck (arrows) at different angulations.

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Case 41 P. Carrascosa, C. Capuñay Cervical Gland Diverticula Clinical History • Twenty-five-year-old female with primary infertility of 12 months duration. • Previous exams: normal transvaginal ultrasound.

• CT-VHSG indication: evaluation of the reproductive system as the first imaging diagnostic test in the infertility work-up. • CT-VHSG was performed with a 64-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval – 100 kV – 150 mAs – 3.16 s scan time. • Effective radiation dose: 0.9 mSv. Images

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Findings and Interpretation CT-VHSG coronal multiplanar reconstruction with soft tissue window (Fig. A) shows a normal small uterine cavity. A little diverticular gland dilatation is visible on the right lateral wall in the lower uterine segment, near the isthmic-cervical region (arrow). The left fallopian tube is partially visualized in the medial and distal regions with a normal appearance

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(arrowhead) and normal spillage of contrast into the peritoneal cavity (asterisk). Volume rendering images with different transparency windows (Figs. B and C) better display the uterus, the uterine glandular dilatation (arrows) and both fallopian tubes (arrowheads) with bilateral spillage of contrast into the peritoneal cavity, showing bilateral positive Cottè test (asterisks). Virtual endoscopy view (Fig. D) shows the diverticular neck (arrow) on the right inferior uterine wall.

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Case 42 P. Carrascosa, C. Capuñay, M. Baronio Cervical Gland Diverticula

Images Clinical History Findings and Interpretation • Twenty-seven-year-old female with primary infertility of 12 months duration. • No relevant past medical or surgical history. • CT-VHSG indication: evaluation of the reproductive system as the first line diagnostic imaging test in the infertility work-up. • CT-VHSG was performed with a 256-slice CT scanner. • CT technical parameters: – 0.625 mm slice thickness – 0.315 mm reconstruction interval

CT-VHSG maximum intensity projections in different views (Figs. A and B) and volume rendering images, frontal and localized views (Figs. C and D) demostrate a small glandular dilatation in the right side of the isthmic-cervical region (arrows). The uterus morphology as well as both fallopian tubes (arrowheads) are normal. There is also normal passage of contrast to the peritoneal cavity (asterisks), with positive Cottè test. Virtual endoscopy view (Fig. E) and conventional hysteroscopy (Fig. F) show the diverticular neck (arrows).

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References 1. Carrascosa P, Capuñay C, Baronio M, et al. 64-Row multidetector CT virtual hysterosalpingography. Abdom Imaging. 2009;34:133– 7. 2. Carrascosa P, Baronio M, Capuñay C, et al. Multidetector computed tomography virtual hysterosalpingography in the investigation of the uterus and fallopian tubes. Eur J Radiol. 2008;67:531–5. 3. Sebastian S, Kalra MK, Mittal P, et al. Can independent coronal multiplanar reformatted images obtained using state-of-the-art MDCT scanners be used for primary interpretation of MDCT of the abdomen and pelvis? A Feasibility Study. Eur J Radiol. 2007;64(3):439–46. 4. Kirchgeorg MA, Prokop M. Increasing spiral CT benefits with postprocessing applications. Eur J Radiol. 1998;28(1):39–54. Review. 5. Chalazonitis A, Tzovara I, Laspas F, et al. Hysterosalpingography: technique and applications. Curr Probl Diagn Radiol. 2009;38 (5):199–205. 6. Lee A, Ying YK, Novy MJ. Hysteroscopy, hysterosalpingography and tubal ostial polyps in infertility patients. J Reprod Med. 1997;42(6):337–41. 7. Radić V, Canić T, Valetić J, et al. Advantages and disadvantages of hysterosonosalpingography in the assessment of the reproductive status of uterine cavity and fallopian tubes. Eur J Radiol. 2005;53(2):268–73. 8. Carrascosa P, Capuñay C, Mariano B, et al. Virtual hysteroscopy by multidetector computed tomography. Abdom Imaging. 2008;33 (4):381–7. 9. Carrascosa P, Capuñay C, Baronio M, et al. 64-Row multidetector CT virtual hysterosalpingography. Abdom Imaging. 2009;34:121– 33.

85 10. Carrascosa P, Capuñay C, Vallejos J, et al. Virtual Hysterosalpingography: a new multidetector CT technique for evaluating the female reproductive system. Radiographics. 2010;30:643–61. 11. Carrascosa P, Capuñay C, Vallejos J, et al. Virtual hysterosalpingography: experience with over 1000 consecutive patients. Abdom Imaging. 2011;36(1):1–14. 12. Baronio M, Carrascosa P, Capuñay C, et al. Diagnostic performance of CT virtual hysteroscopy in 69 consecutive patients. Fertil Steril. 2010;94(Supplement):S77. 13. Gustafsson L, Ponten J, Bergstrom R, et al. International incidence rates of invasive cervical cancer before cytological screening. Int J Cancer. 1997;71:159–65. 14. Womack C, Warren AY. The cervical screeningmuddle. Lancet. 1998;351:1129. 15. Richart RM. Cervical intraepithelial neoplasia. Pathol Annu. 1973;8:301–28. 16. Ho CM, Chien TY, Jeng CM, et al. Staging of cervical cancer: comparison between magnetic resonance imaging, computed tomography and pelvic examination under anesthesia. J Formos Med Assoc. 1992;91:982–90. 17. Scheidler J, Hricak H, Yu KK, et al. Radiological evaluation of lymph node metastases in patients with cervical cancer: a meta-analysis. JAMA. 1997;278:1096–101. 18. Grigsby PW, Dehdashti F, Siegel BA. FDG-PET evaluation of carcinoma of the cervix. Clin Positron Imaging. 1999;2:105–9. 19. Mansour RT, Aboulghar MA. Optimizing the embryo transfer technique. Hum Reprod. 2002;17(5):1149–53. 20. Gómez V, Vallejos J, Baronio M, et al. Cervical evaluation by virtual hysterosalpingography and its comparison with the embryo transfer test. Rev Colomb Radiol. 2016;27(3):4498–504.

Pathology of the Uterine Cavity Carlos Capuñay, Patricia Carrascosa, and Juan Mariano Baronio

The uterus has a critical role in the reproductive system, being involved in the transport of spermatozoids, embryo implantation, and fetal nutrition. The prevalence of infertility by uterine factors has a prevalence of a 10%, including congenital uterine anomalies and acquired pathologies [1–7]. Uterine pathology can be divided into the one that affects the endometrial cavity and the one that affects the uterine wall (myometrium). This chapter is focused on the pathology of the uterine cavity. CT-VHSG provides an excellent evaluation of the uterine cavity via its distention secondary to the instillation of contrast media [2, 5]. In comparison to other imaging diagnostic methods for the evaluation of the endometrial cavity such as the HSG, sonohysterography, and magnetic resonance imaging, CT-VHSG offers in a single non-invasive exam, an integral assessment of the whole female reproductive system in a short period of time (few seconds for CT image acquisition), low radiation dose (0.3– 0.5 mSv), and very low complication rate [8–16]. Hysteroscopy is the gold standard modality for the evaluation of the uterine cavity. It is both a diagnostic and therapeutic procedure performed under anesthesia, and it is most commonly utilized to confirm suspicious findings in other diagnostic methods and treat intrauterine pathology [39, 17]. C. Capuñay (&) Computed Tomography & Magnetic Resonance Imaging Department and Research Department, Diagnóstico MaipúDASA, Av. Maipú 1668, Vicente López, Buenos Aires, B1602ABQ, Argentina e-mail: [email protected] P. Carrascosa Medical Director and Research Department, Diagnóstico MaipúDASA, Av. Maipú 1668, B1602ABQ Vicente López, Buenos Aires, Argentina e-mail: [email protected] J. M. Baronio Fertility and Endoscopic Departments, CEGYR, Viamonte 1432, Ciudad Autónoma de Buenos Aires, C1055ABB, Argentina e-mail: [email protected]

The most common findings of the uterine cavity are synechiae, endometrial hypoplasia, endometrial hyperplasia, endometrial polyps, submucosal myomas and endometrial carcinoma, which will be explained below.

Synechiae Intrauterine adhesions constitute a broad spectrum of pathologic findings, from diffuse, thin, and filmy to thick fibrous bands. They may be located anywhere in the uterine cavity affecting a small area of the uterine wall (minor) or with diffuse involvement and obliteration of the uterine cavity (extensive) (Fig. 1). The American Fertility Society classifies those combining menstrual changes with hysteroscopic and HSG imaging findings [18]. Based on the endometrial cavity involvement, they are divided as (a) mild: adhesion involving one-fourth of uterine cavity; (b) moderate: adhesion involving one-half of uterine cavity; (c) severe: adhesion involving three-fourths or more of uterine cavity. Moreover, the stage of the disease varies according to the uterine cavity involvement, type of adhesions, and menstrual pattern. Synechiae develop secondary to the trauma and destruction of the basal layer of the endometrium, most frequently associated with surgical procedures as dilation and curettage after a miscarriage, delivery, or medical abortion. The risk increases if curetting is performed at a later gestational age (15–30 days after delivery) or in cases of repeated curettage following a miscarriage. Less commonly, other causes include cesarean section, myomectomy, müllerian anomalies surgeries, intrauterine devices, and pelvic infections as genital tuberculosis. The true prevalence of intrauterine synechiae is difficult to establish in the general population. An estimated baseline prevalence is approximately 1.5% based on incidental findings at HSG exams. In patients with a previous uterine procedure, disease prevalence rises sharply up to 21.5% in women with a history of dilation and curettage [19–21].

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Fig. 1 Different types of synechiae, according to a focal (a, b) or diffuse (c) involvement of the endometrial cavity

The clinical manifestations are variable, with a wide spectrum ranging from amenorrhea to menstrual disturbances like hypomenorrhea, menorrhagia, metrorrhagia, and dysmenorrhea to normal menses. Pelvic pain can also be present. Intrauterine adhesions are frequently associated with infertility, repeated abortions, and premature births. An early diagnosis together with an adequate treatment that includes the removal of all adhesions may improve the reproductive outcome of infertile women, according to the type and severity of the adhesions. Based on reports of the American Society of Reproductive Medicine (ASRM), removing mild to moderate uterine adhesions is associated with a full-term pregnancy success rate of 70–80%, while if the adhesions are severe or there is an extensive endometrial damage, full-term pregnancy success rate is only 20–40% after treatment [22, 23]. On CT-VHSG exams, uterine synechiae generally result in irregular filling defects in a lacunar pattern which distort the morphology of the endometrial cavity. When severe, it may be impossible to visualize the entire uterine cavity [15, 16, 24–28]. Adhesions show a wide spectrum of imaging findings on axial and MPR images according to their type and extension. In cases of thin and filmy adhesions, these types of images are the most appropriate for their identification and determination of the extent of the uterine cavity compromise. The most common finding is the visualization of immobile soft tissue linear filling defects, of variable thickness and shape. They can be unique or multiple, and they do not change in shape or position if a second CT acquisition is made. Synechiae can be located anywhere in the uterine cavity and they can distort the uterine silhouette. In occasions, when there is asymmetrical obliteration of one of the uterine horns,

the uterine cavity resembles a unicorn uterus; if the adhesions compromise the uterine fundus with a midline indentation, the endometrial cavity involvement resembles a septate uterus. On MIP images, the imaging findings vary according to the type of adhesions and extension of the uterine cavity involvement and the thickness of the MIP reformation. Modifying the MIP slab thickness (1–20 mm), the radiologist can interactively vary the size of the slab for the best visualization of the intrauterine adhesion. In cases of thin, filmy synechiae, thin-slab (2–3 mm) reformatted MIP images are mandatory for their identification, considering that using a thicker slab (>4 mm) reformations would hide these lesions. In cases of thick fibrous bands or extensive obliteration of the uterine cavity, MIP images show the filling defects distorting the contour of the uterine cavity that can be smaller than its normal size. Volume rendering images display similar imaging findings to MIP images but on a color scale. Thin, tiny adhesions can be overlooked on these three-dimensional reconstructions. In more severe cases, the multiple, irregular, and angulated filling defects involving the uterine cavity are easily defined because the uterine walls that are adhered and the contrast material does not completely surround the defects. Virtual endoscopy allows the endoluminal visualization of the adhesions within the uterine cavity, as lineal images of variable size and thickness projecting into the uterine lumen from one uterine wall to another. When the involvement of the endometrial cavity is extensive, a no contrast or a minimum amount of contrast is present in the uterine cavity, and virtual endoscopy images are limited and the endoluminal visualization of the cavity is not available.

Pathology of the Uterine Cavity

Endometrial Hypoplasia Endometrial hypoplasia is a clinical entity characterized by the thinning and atrophy of the endometrium, and it is frequently observed in patients with changing hormonal levels. The reduction of exposure to estrogen after menopause, ovary dysfunction, or secondary to medical intervention (e.g., oral contraceptives) may cause thinning of the endometrium. The described changes in the endometrium produce a fussy and diffuse irregularity in the uterine walls that can be appreciated on the MPR and volume rendering images as a fine diffuse irregular contour of the entire uterine cavity, conserving its normal size and shape. These parietal irregularities can also be identified from the inside of the endometrial cavity on the virtual endoscopy images [28, 29].

Endometrial Hyperplasia Endometrial hyperplasia is a clinical condition in which the endometrium becomes abnormally thick in response to an excess of estrogen levels in the absence of progesterone secretion. These hormonal imbalances make the endometrium continue to grow with the consequent absence of menstruation and normal shedding of the endometrial lining. The most common type of endometrial hyperplasia is simple hyperplasia, and it has a very small risk of becoming cancer. Conversely, atypical endometrial hyperplasia is a premalignant condition of the endometrium, and it has a risk of becoming cancer in about 8% to 29% of cases if it is not treated. The most common symptom of atypical endometrial hyperplasia is abnormal vaginal bleeding; other less common symptoms are pathological vaginal discharges or an abnormal Pap test result. Ultrasound is the primary imaging modality in this clinical setting. The most common imaging finding is a homogeneous abnormal increase in the endometrial thickness >10 mm, measured on days 5–10 of a woman’s cycle. In some cases, the endometrial thickening can be asymmetric or focal with surface irregularity, or associated with cystic changes. On CT-VHSG, the appearance of simple endometrial hyperplasia is non-specific and cannot reliably allow differentiation between a normal secretory endometrium and a homogeneous smooth increase in endometrial thickness. However, atypical endometrial hyperplasia show on axial and MPR images, irregular endometrial thickening and pseudopolypoid mass lesions projecting into the endometrial cavity without a predominant lesion. Volume rendering images and virtual endoscopy images show an irregular uterine cavity of small size with longitudinal thickened,

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scalloped folds. Elevated pseudopolypoid parietal lesions protruding into the lumen of the endometrial cavity are visible on the virtual endoluminal images [28].

Endometrial Polyps An endometrial or uterine polyp is a hormonal-independent overgrowth of the endometrium containing glands, stroma, and blood vessels that project into the uterine cavity. They are the most frequently observed pathological finding in the uterus and they affect all age groups, most common between ages 40–49 [30]. Benign lesions in nature, a small minority (0.5%) may have atypical or malignant endometrial carcinoma [31–33]. Prevalence of endometrial polyps is unclear. Their presence is implicated in about 50% of cases of abnormal uterine bleeding. They are also associated with infertility, with an incidence of 3.8–38.5% in primary infertility and 1.8–17% in secondary infertility; they may also have an impact on recurrent implantation failure [34]. The actual causal relationship remains unclear; however, two main hypotheses have been suggested. One theory is a mechanical obstruction on the sperm transport by blocking the cervical canal or entrance into the fallopian tube. Also, the polyp, as a space-occupying lesion could interfere in the implantation of the embryo. The other hypothesis is that polyps may cause infertility due to biochemical effects inhibiting implantation of the embryo. Endometrial polyp size is variable, ranging from scarce millimeters (