The retroperitoneum and pelvic extraperitoneum are complex anatomic spaces that contain numerous vital structures such as major vessels, lymphatics, nerves, and abdominopelvic organs. These regions are divided by fascial planes into distinct compartments with defined boundaries and contents, which guide the spread of disease within and beyond the abdominopelvic cavity. The retroperitoneum represents the abdominal part of the extraperitoneum located posterior to the parietal peritoneum and extends from the diaphragm superiorly to the pelvic brim inferiorly. The pelvic extraperitoneum, also referred to as the subperitoneal space, is located below the peritoneal reflection and surrounds the pelvic organs. The extraperitoneal spaces are susceptible to numerous diseases and pathologic processes, reflecting the diversity of structures they contain. These conditions can be congenital, inflammatory, infectious, neoplastic, or traumatic in nature. Imaging modalities such as CT and MRI are indispensable for identifying normal anatomy and characterizing pathologic processes. Patterns of disease spread in these compartments depend on the structures involved and the nature of the disease process. Malignancies often spread via lymphatic and hematogenous routes, while inflammatory and infectious processes tend to track along fascial planes. Vascular pathologic processes, including aneurysms and dissections, can cause secondary effects on adjacent structures. Understanding the anatomic landmarks, imaging features, and patterns of disease spread within the retroperitoneum and pelvic extraperitoneum is critical for accurate diagnosis and effective disease management. ©RSNA, 2026 Supplemental material is available for this article.

The female urethra can be affected by numerous pathologic conditions, many of which are infrequent and often underdiagnosed, particularly before the introduction of MRI. Diagnosing urethral pathologic conditions is challenging due to ambiguous signs and symptoms, nonspecific physical examinations, atypical presentations (such as benign conditions mimicking malignant disorders), and large lesions. Various imaging techniques, including transperineal or transvaginal US and MRI, are essential for accurate anatomic and tissue characterization. Female urethral pathologic conditions can be categorized into cystic lesions (with urethral diverticulum as the most common), benign and malignant solid urethral lesions, and iatrogenic lesions. Defining the location of the pathologic finding is the first step in radiologic diagnosis. By analyzing tissue characteristics (cystic versus noncystic), shape, morphology, and location (including urethral dependence and relationship to the pubic symphysis), an accurate diagnosis can often be achieved. Identifying whether a lesion is urethral-dependent helps distinguish between urethral and other conditions, such as Bartholin gland and Gartner duct cysts. Radiologists must recognize these features to determine the most appropriate diagnostic and therapeutic strategies. ©RSNA, 2025 Supplemental material is available for this article.

Endometrial cancer is the most common gynecologic malignancy in developed countries, exhibiting significant heterogeneity in prognosis and management. This review highlights the critical role of multimodality imaging-including ultrasound, MRI, CT, and PET/CT-at every stage of care, from initial diagnosis and risk stratification to surgical planning, treatment selection, and surveillance. Imaging enables accurate tumor characterization, local and distant staging, and detection of nodal and peritoneal disease, but also significantly influences the choice between conservative and radical surgery, sentinel lymph node mapping, and individualized adjuvant therapies. Advances in functional and quantitative imaging, such as DWI, have improved precision in disease grading and treatment tailoring. Core learning points include the necessity of standardized management algorithms, the importance of multiparametric assessments for optimal risk stratification, and the evolving potential of imaging biomarkers to personalize endometrial cancer management and improve patient outcomes.

Advances in imaging techniques have evolved, allowing for early noninvasive diagnosis and improved management of high-risk patients with hepatocellular carcinoma (HCC). The hallmark imaging features of HCC on multiphasic cross-sectional imaging can be explained by the multistep process of hepatocarcinogenesis and is seen in 60

BACKGROUND. CT with adrenal-washout protocol (hereafter, adrenal-protocol CT) is commonly performed to distinguish adrenal adenomas from other adrenal tumors. However, the technique's utility among heterogeneous nodules is not well established, and the optimal method for placing ROIs in heterogeneous nodules is not clearly defined. OBJECTIVE. The purpose of our study was to determine the diagnostic performance of adrenal-protocol CT to distinguish adenomas from nonadenomas among heterogeneous adrenal nodules and to compare this performance among different methods for ROI placement. METHODS. This retrospective study included 164 patients (mean age, 59.1 years; 61 men, 103 women) with a total of 164 heterogeneous adrenal nodules evaluated using adrenal-protocol CT at seven institutions. All nodules had an available pathologic reference standard. A single investigator at each institution evaluated the CT images. ROIs were placed on portal venous phase images using four ROI methods: standard ROI, which refers to a single large ROI in the nodule's center; high ROI, a single ROI on the nodule's highest-attenuation area; low ROI, a single ROI the on nodule's lowest-attenuation area; and average ROI, the mean of the three ROIs on the nodule's superior, middle, and inferior thirds using the approach for the standard ROI. ROIs were then placed in identical locations on unenhanced and delayed phase images. Absolute washout was determined for all methods. RESULTS. The nodules comprised 82 adenomas and 82 nonadenomas (36 pheochromocytomas, 20 metastases, 12 adrenocortical carcinomas, and 14 nodules with other pathologies). The mean nodule size was 4.5 +/- 2.8 (SD) cm (range, 1.6-23.0 cm). Unenhanced CT attenuation of 10 HU or less exhibited sensitivity and specificity for adenoma of 22.0% and 96.3% for standard-ROI, 11.0% and 98.8% for high-ROI, 58.5% and 84.1% for low-ROI, and 30.5% and 97.6% for average-ROI methods. Adrenal-protocol CT overall (unenhanced attenuation <= 10 HU or absolute washout of >= 60%) exhibited sensitivity and specificity for adenoma of 57.3% and 84.1% for the standard-ROI method, 63.4% and 51.2% for the high-ROI method, 68.3% and 62.2% for the low-ROI method, and 59.8% and 85.4% for the average-ROI method. CONCLUSION. Adrenal-protocol CT has poor diagnostic performance for distinguishing adenomas from nonadenomas among heterogeneous adrenal nodules regardless of the method used for ROI placement. CLINICAL IMPACT. Adrenal-protocol CT has limited utility in the evaluation of heterogeneous adrenal nodules.

433 Background: LEN+PEM is an approved first-line therapy for aRCC. In the CLEAR study, it produced a 71% objective response rate (ORR), an 18% complete response rate, and improved progression-free survival (PFS) and overall survival (OS) compared to sunitinib. CABO is approved as second and later line therapy for aRCC. We explored the efficacy of CABO in pts with aRCC after treatment with LEN+PEM. Methods: This is a retrospective study of pts with aRCC who received CABO after LEN+PEM at our institution from 12/2019 to 8/2023. Demographics and clinical data were abstracted from the EMR. A blinded radiologist assessed tumor response using RECIST v1.1. We measured PFS, time on therapy (TOT) and OS from start date of CABO. Results: 22 pts were analyzed (Table 1). Median follow up was 7.7 months (mo); 11 pts received LEN+PEM on the HOPE 111 trial (NCT02501096). Among all 22 pts, 11 (50%) had a partial response (PR), 5 (22.7%) had stable disease (SD), and 6 (27.3%) had progressive disease (PD) on LEN+PEM. Median TOT with LEN+PEM was 7.4 mo (range: 1.8-29). 20 pts (90.9%) discontinued LEN+PEM due to PD, 1 pt (4.5%) due to fatigue, and 1 pt (4.5%) due to elevated liver enzymes. 17 pts received CABO right after LEN+PEM; 3 pts received 1 line and 2 pts received 2 lines of therapy before CABO after LEN+PEM. Of 19 pts with evaluable radiographic response on CABO, 1 pt had a PR (ORR 5.3%, PFS 16.1 mo) and 3 pts had SD for ≥6 mo. Median TOT with CABO was 4.3 mo (range: 0.2-18.2); 13 pts (59.1%) took CABO for ≥4 mo, 7 pts (31.8%) took it for ≥6 mo, of which 3pts receivedpalliative radiation andcontinued CABO therapy beyond PD. Median PFS and median OS with CABO were 4.1 mo (range: 1.2-16.1) and 8.1 mo (range: 0.8-22.5), respectively. At time of analysis, 4 pts were still taking CABO (3 SD, 1 not yet evaluated); 15 pts discontinued CABO: 12 for PD, 1 for Grade 3 hand-foot skin reaction, 1 per pt request, and 1 for transition to hospice; 3 pts died during CABO therapy (bowel obstruction [1], COVID-19 [1], cardiac arrest [1]). Adverse events attributed to CABO were consistent with published reports. Conclusions: In this cohort of heavily pretreated pts who received CABO after LEN+PEM, CABO demonstrated a modest clinical benefit in a minority of pts, underscoring the need to develop effective novel therapies for aRCC. [Table: see text]

Mentorship is a fundamental part of professional and personal growth. Over time, the fabric of mentorship has been transforming from typical one-on-one mentor-mentee relationship to other types including peer, group, speed, and virtual mentoring. When the COVID-19 pandemic hit, it caused major disruptions in many facets of life and career, including mentoring. In response to the COVID-19 pandemic, live meetings were canceled, and social distancing measures were enacted at many institutions. Thus, the traditional set-up, with a face-to-face mentor and mentee interaction, was impossible. Many virtual platforms were utilized to navigate through these restrictions. In this review, we highlight challenges in mentorship during the COVID-19 pandemic and how we implemented different strategies to promote mentorship.

Gastrointestinal bleeding (GIB) among cancer patients is a major source of morbidity and mortality. Although a wide variety of etiologies contribute to GIB, special considerations should be made for cancer-related factors such as the type of malignancy, location and extent of disease, hemostatic parameters, and treatment effects. Key imaging modalities used to evaluate GIB include computed tomography angiography (CTA), radionuclide imaging, and catheter-based angiography. Understanding the cancer and treatment history and recognizing the associated imaging manifestations are important for identifying the source and potential causes of GIB in cancer patients. This article will review the common clinical presentations, causes, imaging manifestations, and angiographic management of GIB in cancer patients.

Neurofibromatosis type 1 (NF1) and neurofibromatosis type 2 (NF2) are autosomal dominant inherited neurocutaneous disorders or phakomatoses secondary to mutations in the NF1 and NF2 tumor suppressor genes, respectively. Although they share a common name, NF1 and NF2 are distinct disorders with a wide range of multisystem manifestations that include benign and malignant tumors. Imaging plays an essential role in diagnosis, surveillance, and management of individuals with NF1 and NF2. Therefore, it is crucial for radiologists to be familiar with the imaging features of NF1 and NF2 to allow prompt diagnosis and appropriate management. Key manifestations of NF1 include café-au-lait macules, axillary or inguinal freckling, neurofibromas or plexiform neurofibromas, optic pathway gliomas, Lisch nodules, and osseous lesions such as sphenoid dysplasia, all of which are considered diagnostic features of NF1. Other manifestations include focal areas of signal intensity in the brain, low-grade gliomas, interstitial lung disease, various abdominopelvic neoplasms, scoliosis, and vascular dysplasia. The various NF1-associated abdominopelvic neoplasms can be categorized by their cellular origin: neurogenic neoplasms, interstitial cells of Cajal neoplasms, neuroendocrine neoplasms, and embryonal neoplasms. Malignant peripheral nerve sheath tumors and intracranial tumors are the leading contributors to mortality in NF1. Classic manifestations of NF2 include schwannomas, meningiomas, and ependymomas. However, NF2 may have shared cutaneous manifestations with NF1. Lifelong multidisciplinary management is critical for patients with either disease. The authors highlight the genetics and molecular pathogenesis, clinical and pathologic features, imaging manifestations, and multidisciplinary management and surveillance of NF1 and NF2. Online supplemental material is available for this article. ©RSNA, 2022.

Abstract Purpose The current undergraduate radiology education predominantly integrates radiology with other disciplines during preclerkship years and is often taught by nonradiologists. Early exposure to radiology and profound understanding of scientific fundamentals of imaging modalities and techniques are essential for a better understanding and interest in the specialty. Furthermore, the COVID-19 pandemic–related impact on in-person medical education aggravated the need for alternative virtual teaching initiatives to provide essential knowledge to medical students. Methods The authors designed an online 7-session course on the principles of imaging modalities for medical students and fresh graduates in the United States and abroad. The course was delivered online and taught by radiologists from different US institutions. Pretests and posttests were delivered before and after each session, respectively, to assess change in knowledge. At the end of the course, a survey was distributed among students to collect their assessment and feedback. Results A total of 162 students and interns initially enrolled in the program by completing a sign-up interest form. An average of 65 participants attended each live session, with the highest attendance being 93 live attendees. An average of 44 attendees completed both the pretest and posttest for each session. There was a statistically significant increase in posttest scores compared with pretest scores (P < 0.01) for each session; on average, the posttest scores were 48% higher than the pretest scores. A total of 84 participants answered the end-of-course survey. A total of 11% of the respondents described themselves as first year, 17% as second year, 18% as third year, 21% as fourth year, and 33% as “other.” Attendees were enrolled in medical schools across 21 different countries with 35% of the respondents studying medicine in the United States. More than 76% of the respondents stated that they “strongly agree” that the program increased their understanding of radiology, increased their interest in radiology, and would be useful in their clinical practice in the future. Eighty-three percent of the respondents stated that they “strongly agree” that “this course was a worthwhile experience.” Particularly, more than 84% of the respondents stated that among the most important components in enhancing their understanding of radiology were “the interpretation of normal imaging” and “interpretation of clinical cases.” Ninety-two percent of the respondents stated that “the amount of effort to complete the requirements for this program was just right.” Participants were also asked to rate each of the 8 sessions using the following scale: poor = 1 point, fair = 2, good = 3, and excellent = 4. The average rating for all 8 sessions was 3.61 points (SD = 0.55), which translates to 96% of the sessions being rated good or excellent. Eighty percent of the participants reported that the topics presented in the program were “excellent and clinically important to learn,” and 20% of the participants reported that the topics presented were “good and somewhat important to learn.” The participants were asked to evaluate their confidence regarding basic radiology skills before and after the program using the following scale: not confident at all = 1 point, somewhat confident = 2, moderately confident = 3, and very confident = 4. Figure 2 summarizes the responses of the participants. Conclusions An online course to teach the fundamentals of imaging modalities could be delivered through a webinar format to medical students and interns in several countries to address the potential gaps in radiology education, therefore increasing their understanding of the different imaging modalities and their proper use in medicine.

HomeRadioGraphicsVol. 42, No. 1 PreviousNext Education CornerFree AccessTurning Radiology Educational Challenges into Opportunities: The Digital FrontierKhaled M. Elsayes , Serageldin Kamel, Mindy X. WangKhaled M. Elsayes , Serageldin Kamel, Mindy X. WangAuthor AffiliationsFrom the Department of Abdominal Radiology (K.M.E.) and Department of Lymphoma and Myeloma (S.K.), The University of Texas MD Anderson Cancer Center, 1400 Pressler St, Houston, TX 77030; and Department of Diagnostic and Interventional Imaging, The University of Texas Health Science Center at Houston, Houston, Tex (M.X.W.).Address correspondence to K.M.E. (e-mail: [email protected]).Khaled M. Elsayes Serageldin KamelMindy X. WangPublished Online:Jan 6 2022https://doi.org/10.1148/rg.210203MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In Since the discovery of x-rays in the 19th century by Wilhelm Roentgen, radiology has played a key role in modern medicine as imaging technologies continued to advance over the years. The introduction of medical imaging storage technologies and clinical decision support systems provided radiology educators with a wealth of teaching assets. However, remote learning technology has not been used in radiology to its fullest potential until recently (1). The complexity of today’s imaging modalities warrants the expansion of radiologists’ roles in teaching and medical school curricula (2,3).For years, medical students have been learning radiology via didactic lectures and observational experience while shadowing radiologists in the reading room. This in-person format was disrupted in early 2020 as COVID-19 pandemic-related restrictions were enforced by public health authorities, medical schools, and hospitals. Amid the uncertainty and profound impacts on radiology programs, attendings and trainees have switched to remote working environments and virtual learning. This paradigm shift served as an opportunity for educators to take advantage of the advancements in communication, e-learning, and imaging technologies to address the educational needs of many students and trainees. These were defining moments and were key in guiding the trajectory of future radiology education.A four-domain framework has been described for successful medical education leadership: (a) intrapersonal, where leaders realize their motivation, strengths, and limitations; (b) interpersonal, where leaders get engaged with people and bring out the best in them; (c) organizational, where leaders have a vision and establish harmonization and inclusion among their team; and (d) systemic, where leaders learn from others, reflect on experiences, and look for opportunities (4). When we examine the early days of the pandemic, we find a strong presence of the intrapersonal domain in many educators who were motivated by the concerns of their students and felt an urge to help. This motivation ignited the initiation of many educational projects that would have been difficult without fulfilling the second domain of the aforementioned framework. As Helen Keller once said, “Alone we can do so little; together we can do so much.” A successful leader could fulfill the interpersonal domain through engaging with a network of peers and mentees who could help with different aspects according to their strengths. It is known that personal and strategic networking with lateral and vertical relationships is a key factor in the success of big projects (5).We describe here a successful case study of a group of radiology educators. The journey started during the spring of 2020, with the launch of the Online Liver Imaging Course (OLIC), a collective effort by renowned radiologists in the United States to help radiologists across the world through a series of 28 webinars discussing in-depth topics on liver imaging. There was an impressive number of interested learners, with more than 1400 radiologists from 37 countries signing up to attend the live sessions and thousands more who viewed the on-demand videos (6). This first milestone in the journey to provide a comprehensive high-quality educational experience in radiology showed tremendous success, with most attendees saying that they enjoyed the experience and that the course exceeded their expectations. This positive feedback confirmed the benefits of online education and was the nidus to the launch of the Academy of Online Radiology Education (ACORE) to develop additional innovative courses (7).The success of the OLIC led to the consideration of another educational gap: medical student education in radiology. This was another opportunity to design a curriculum in which students would learn about radiology in the context of clinical presentations, workup, and management of various case scenarios through 10 webinar series from May to June 2020. These lectures consisted of a multidisciplinary team composed of a radiologist, an internist, and a surgeon. Enrollees included medical students from six Texas medical schools. Aside from the multidisciplinary teaching approach, this course fully used simple tools to enhance learning through live polls, discussions, lecture handouts, and comprehensive assessments. Student leadership was a critical factor in the success of this project. Recruited student ambassadors led the efforts in advertising this opportunity and communicating with their peers and educators, which led to the creation of tailored educational materials and a collaborative environment throughout the course.At this point, it was important to keep the momentum of this mission. Therefore, ACORE was established in July 2020 to serve as a platform for radiology educators where accessible education is made available “to everyone everywhere.” The platform swiftly grew to gain recognition as one of the open-access radiology education resources (1).Since its inception, ACORE has delivered 75 webinars by renowned experts to thousands of practicing radiologists and radiology residents. Within one year, ACORE garnered over 50 000 active website users and over 16 000 followers on social media platforms. Educational videos on ACORE’s YouTube channel had over 88 000 views with a combined watch time of 16 200 hours. In addition, a course on the principles of radiology has been taught to thousands of students in four countries and is set to launch in Brazil, with over 2000 students signing up. Aside from webinars and courses, ACORE has provided various collaborative opportunities for learners, trainees, and educators. ACORE’s junior editors have prepared over 90 “What’s New” blogs in various radiology subspecialties, broadcasting the latest research in each field in more than six languages.Medical students also play an integral role in the success of the medical student courses. Trainee involvement fosters leadership and collaborative skills, which are very favorable traits in our future generation of physicians. The diligent efforts by our team cast a wide net, making radiology education accessible to people all over the world (Figure). The Table highlights ACORE’s tireless and inspiring team and all of our broadcasted educational events thus far. These educational endeavors have been published in over 10 articles.Figure. Map shows the geographic locations of learners involved in the Online Liver Imaging Course (OLIC) and the Academy of Online Radiology Education (ACORE).Figure.Download as PowerPointOpen in Image Viewer ACORE Collaborative Team Members and Educational Events Delivered to an International AudienceWhile the digital world has been available as an educational tool long before health care professionals began widely using it, this tool is now one of the only means of medical education, especially amid the COVID-19 pandemic (8,9). Moreover, many studies have shown the effectiveness of online teaching of radiology for both trainees and medical students. A shift from the traditional pedagogical models to an interactive, accessible model should continue to address the evolving needs of our learners (10).ConclusionThe COVID-19 pandemic started off as a challenge that turned into an opportunity to transform the way we teach. Mentors’ efforts to support their mentees during challenging times could be multiplied to help thousands around the world. Networking, leadership, and technologic advancements were key assets to launch a successful radiology platform, such as ACORE, and enable it to reach thousands of learners across the globe. To this day, we continue the mission, delivering hundreds of lectures, courses, and blogs to our global audience. Although many would consider this initiative a success, it is just the beginning of humble efforts to unite and empower thousands of radiology colleagues and learners around the world and engage hundreds of expert colleagues and learners in leading and organizing on this novel platform.Disclosures of conflicts of interest.— K.M.E. Editorial board member of RadioGraphics.K.M.E. has provided disclosures (see end of article); all other authors have disclosed no relevant relationships.References1. Fotos JS, Beatty-Chadha J, Goldenberg MDF. Purposeful remote radiology education: strategies and recommendations. RadioGraphics 2021;41(4):E109–E116. Link, Google Scholar2. Chew C, Cannon P, O’Dwyer PJ. Radiology for medical students (1925-2018): an overview. BJR Open 2020;2(1):20190050. Crossref, Medline, Google Scholar3. Poot JD, Hartman MS, Daffner RH. Understanding the US medical school requirements and medical students’ attitudes about radiology rotations. Acad Radiol 2012;19(3):369–373. Crossref, Medline, Google Scholar4. Lieff S, Albert M. What do we do? Practices and learning strategies of medical education leaders. Med Teach 2012;34(4):312–319. Crossref, Medline, Google Scholar5. Ibarra H, Hunter M. How leaders create and use networks. Harv Bus Rev 2007;85(1):40–47, 124. Medline, Google Scholar6. Elsayes KM, Marks RM, Kamel S, et al. Online Liver Imaging Course; pivoting to transform radiology education during the SARS-CoV-2 pandemic. Acad Radiol 2021;28(1):119–127. Crossref, Medline, Google Scholar7. Elsayes KM, Khan ZA, Kamel S, et al. Multidisciplinary approach in teaching diagnostic radiology to medical students: the development, implementation, and evaluation of a virtual educational model. J Am Coll Radiol 2021;18(8):1179–1187. Crossref, Medline, Google Scholar8. Bandukwala T, Arora S, Athreya S. Net assets: review of online radiology resources. Part I. Educational resources. Radiology 2011;261(2):350–356. Link, Google Scholar9. Bandukwala T, Arora S, Athreya S. Net assets: review of online radiology resources. Part II. Organizations and societies. Radiology 2012;262(1):19–24. Link, Google Scholar10. Hopkins L, Hampton BS, Abbott JF, et al. To the point: medical education, technology, and the millennial learner. Am J Obstet Gynecol 2018;218(2):188–192. Crossref, Medline, Google ScholarArticle HistoryReceived: Aug 16 2021Accepted: Aug 18 2021Published online: Jan 06 2022Published in print: Jan 2022 FiguresReferencesRelatedDetailsCited ByDiagnostic radiology training for medical students - a Brazilian multicenter surveyNatallyHorvat, Brunna Clemente deOliveira, Daniella BrazParente, Julia Werneck Paulino Soares deSouza, Livia RomaBarbosa, Isabel VerasBeleza, Géssica SilvaCazagrande, Rackel SilvaResende, Scott AndrewRohren, ParthPatel, Mohamed E.Badawy, Munevver NurDuran, UmaymaAbdullatif, SerageldinKamel, JacobStanietzky, Khaled M.Elsayes2023 | einstein (São Paulo), Vol. 31Recommended Articles Social Media Tools for Department and Practice Communication and Branding in the Digital AgeRadioGraphics2018Volume: 38Issue: 6pp. 1773-1785Precision Twitter: Using Twitter for Professional AdvancementRadioGraphics2021Volume: 41Issue: 6pp. E169-E170Radiology Preparedness in the Ongoing Battle against COVID-19: Experiences from Large to Small Public Hospitals in SingaporeRadiology: Cardiothoracic Imaging2020Volume: 2Issue: 2Special Report of the RSNA COVID-19 Task Force: Crisis Leadership of Major Health System Radiology Departments during COVID-19Radiology2021Volume: 299Issue: 1pp. E187-E192Artificial Intelligence and Radiology EducationRadiology: Artificial Intelligence2022Volume: 5Issue: 1See More RSNA Education Exhibits A Guide to Using YouTube Live for Radiology EducationDigital Posters2022A New (Digital) Era in Medical Journalism: Leveraging Social Media and Other Online Tools to Increase Reach and EngagementDigital Posters2022Hidden Gem: Ultrasonography Detection & Differentiation of Sclerosing CholangitisDigital Posters2022 RSNA Case Collection Peroneal intraneural Ganglion CystRSNA Case Collection2021Traumatic open globe rupture RSNA Case Collection2021Gangrenous Acute appendicitisRSNA Case Collection2020 Vol. 42, No. 1 Abbreviations Abbreviations: ACORE Academy of Online Radiology Education OLIC Online Liver Imaging Course Metrics Altmetric Score PDF download

Adrenal cystic lesions are generally rare and encompass a wide spectrum of benign and malignant entities. Increased utilisation of cross-sectional imaging has led to increased detection of incidentally discovered adrenal lesions. Many of these lesions are cystic or solid with cystic changes, and the majority are benign; however, some may represent malignant lesions and/or even metastases. Therefore, it is vital to characterise these lesions appropriately and follow-up with laboratory tests and imaging if necessary. Key imaging techniques include computed tomography (CT) and magnetic resonance imaging (MRI). Other supplemental imaging tools include metaiodobenzyl-guanidine (MIBG) scintigraphy and 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography (FDG-PET). Accurate diagnosis of adrenal cystic lesions is crucial in guiding appropriate evaluation and management of these patients. This review highlights the clinical presentations, pathological and imaging features, and management of cystic adrenal lesions.

Vascular anomalies encompass a spectrum of tumors and malformations that can cause significant morbidity and mortality in children and adults. Use of the International Society for the Study of Vascular Anomalies (ISSVA) classification system is strongly recommended for consistency. Vascular anomalies can occur in isolation or in association with clinical syndromes that involve complex multifocal lesions affecting different organ systems. Thus, it is critical to be familiar with the differences and similarities among vascular anomalies to guide selection of the appropriate imaging studies and possible interventions. Syndromes associated with simple vascular malformations include hereditary hemorrhagic telangiectasia, blue rubber bleb nevus syndrome, Gorham-Stout disease, and primary lymphedema. Syndromes categorized as vascular malformations associated with other anomalies include Klippel-Trenaunay-Weber syndrome, Parkes Weber syndrome, Servelle-Martorell syndrome, Maffucci syndrome, macrocephaly-capillary malformation, CLOVES (congenital lipomatous overgrowth, vascular malformations, epidermal nevi, and scoliosis, skeletal, and spinal anomalies) syndrome, Proteus syndrome, Bannayan-Riley-Ruvalcaba syndrome, and CLAPO (capillary malformations of the lower lip, lymphatic malformations of the face and neck, asymmetry of the face and limbs, and partial or generalized overgrowth) syndrome. With PHACES (posterior fossa malformations, hemangiomas, arterial anomalies, cardiac defects and/or coarctation of the aorta, eye abnormalities, and sternal clefting or supraumbilical raphe) syndrome, infantile hemangiomas associated with other lesions occur. Diagnostic and interventional radiologists have important roles in diagnosing these conditions and administering image-guided therapies-embolization and sclerotherapy, and different ablation procedures in particular. The key imaging features of vascular anomaly syndromes based on the 2018 ISSVA classification system and the role of interventional radiology in the management of these syndromes are reviewed. Online supplemental material is available for this article.©RSNA, 2022.

Uterine fibroids are the most common gynecologic neoplasm. Although non-degenerated fibroids are easily identifiable on imaging, degenerated fibroids, fibroid variants, and fibroids with unusual growth patterns can constitute a diagnostic dilemma. Identification of these abnormal morphologic features can alter the diagnosis of presumed uterine fibroids and hence change management plans. This article reviews the typical and atypical radiologic imaging features of uterine fibroids, with an emphasis on the pitfalls, mimics, and radiologically identifiable features that can alter clinical management plans.

Pancreatic neuroendocrine neoplasms (panNEN) are a heterogeneous group of tumors with differing pathological, genetic, and clinical features. Based on clinical findings, they may be categorized into functioning and nonfunctioning tumors. Adoption of the 2017 World Health Organization classification system, particularly its differentiation between grade 3, well-differentiated pancreatic neuroendocrine tumors (panNET) and grade 3, poorly-differentiated pancreatic neuroendocrine carcinomas (panNEC) has emphasized the role imaging plays in characterizing these lesions. Endoscopic ultrasound can help obtain biopsy specimen and assess tumor margins and local spread. Enhancement patterns on computed tomography (CT) and magnetic resonance imaging (MRI) may be used to classify panNEN. Contrast enhanced MRI and diffusion-weighted imaging have been reported to be useful for characterization of panNEN and quantifying metastatic burden. Current and emerging radiotracers have broadened the utility of functional imaging in evaluating panNEN. Fluorine-18 fluorodeoxyglucose positron emission tomography (PET)/CT and somatostatin receptor imaging such as Gallium-68 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-octreotate PET/CT may be useful for improved identification of panNEN in comparison to anatomic modalities. These new techniques can also play a direct role in optimizing the selection of treatment for individuals and predicting tumor response based on somatostatin receptor expression. In addition, emerging methods of radiomics such as texture analysis may be a potential tool for staging and outcome prediction in panNEN, however further investigation is required before clinical implementation.

Tuberous sclerosis complex (TSC) is a relatively rare autosomal dominant neurocutaneous disorder secondary to mutations in the TSC1 or TSC2 tumor suppressor genes. Although manifestation of the classic triad of seizures, intellectual disability, and facial angiofibromas may facilitate timely diagnosis of TSC, the multisystem features that may indicate TSC in the absence of these manifestations remain highly variable. In addition, patients with TSC are at risk of developing multiple benign and malignant tumors in various organ systems, resulting in increased morbidity and mortality. Thus, imaging plays a critical role in diagnosis, surveillance, and management of patients with TSC. It is crucial that radiologists be familiar with TSC and the various associated imaging features to avoid a delayed or incorrect diagnosis. Key manifestations include cortical dysplasias, subependymal nodules, subependymal giant cell astrocytomas, cardiac rhabdomyomas, lymphangioleiomyomatosis, and angiomyolipomas. Renal angiomyolipomas in particular can manifest with imaging features that mimic renal malignancy and pose a diagnostic dilemma. Other manifestations include dermatologic and ophthalmic manifestations, renal cysts, renal cell carcinomas, multifocal micronodular pneumocyte hyperplasia, splenic hamartomas, and other rare tumors such as perivascular epithelioid tumors. In addition to using imaging and clinical features to confirm the diagnosis, genetic testing can be performed. In this article, the molecular pathogenesis, clinical manifestations, and imaging features of TSC are reviewed. Current recommendations for management and surveillance of TSC are discussed as well. ©RSNA, 2021.