Society of Radiologists in Ultrasound Consensus on Routine Pelvic US for Endometriosis.

Endometriosis is a prevalent and potentially debilitating condition that mostly affects individuals of reproductive age, and often has a substantial diagnostic delay. US is usually the first-line imaging modality used when patients report chronic pelvic pain or have issues of infertility, both common symptoms of endometriosis. Other than the visualization of an endometrioma, sonologists frequently do not appreciate endometriosis on routine transvaginal US images. Given a substantial body of literature describing techniques to depict endometriosis at US, the Society of Radiologists in Ultrasound convened a multidisciplinary panel of experts to make recommendations aimed at improving the screening process for endometriosis. The panel was composed of experts in the imaging and management of endometriosis, including radiologists, sonographers, gynecologists, reproductive endocrinologists, and minimally invasive gynecologic surgeons. A comprehensive literature review combined with a modified Delphi technique achieved a consensus. This statement defines the targeted screening population, describes techniques for augmenting pelvic US, establishes direct and indirect observations for endometriosis at US, creates an observational grading and reporting system, and makes recommendations for additional imaging and patient management. The panel recommends transvaginal US of the posterior compartment, observation of the relative positioning of the uterus and ovaries, and the uterine sliding sign maneuver to improve the detection of endometriosis. These additional techniques can be performed in 5 minutes or less and could ultimately decrease the delay of an endometriosis diagnosis in at-risk patients.

The Confounding Ultrasound Diagnosis of Ectopic Pregnancy: Lessons From Peer Learning.

ABSTRACT: As the treatment of ectopic pregnancy (EP) has shifted increasingly to medical therapies, the ultrasound (US) diagnosis of EP must necessarily favor specificity over sensitivity. Our review of peer learning cases of EP and early intrauterine pregnancies found several types of pitfalls and problems, which will be described in this essay. These issues include the following: differentiation of tubal EP from a corpus luteum by echogenicity relative to ovarian parenchyma, push technique, and claw sign; how to distinguish interstitial EP from eccentrically located intrauterine pregnancies (angular); use of trophoblastic flow in abnormal intrauterine locations to help identify cesarean scar or cervical implantations; recognition that hemoperitoneum without visualized EP may be due to EP or hemorrhagic cyst; and that distinguishing an abortion in progress from a pregnancy of unknown location may not always be possible and requires clinical follow-up. This essay will also illustrate the consensus terminology that our radiology department has developed in conjunction with our obstetrics and gynecology colleagues to communicate clear diagnoses and reduce the risk of misdiagnosis and adverse outcomes.

Benign-appearing Incidental Adnexal Cysts at US, CT, and MRI: Putting the ACR, O-RADS, and SRU Guidelines All Together.

Adnexal cysts are a common incidental finding at US, CT, and MRI but have historically caused a diagnostic dilemma for determining when to follow up and how to manage them. Characteristic imaging features of simple adnexal cysts include a simple fluid collection with smooth walls and no solid or vascular components. Day-to-day practice guidelines were recently updated to reflect the overwhelming evidence that incidental cystic adnexal masses are almost always benign. Three major consensus articles on adnexal cystic masses were published between 2019 and 2020: the Society of Radiologists in Ultrasound (SRU) consensus update on adnexal cysts, the Ovarian-Adnexal Reporting and Data System (O-RADS) US consensus guideline, and the American College of Radiology (ACR) white paper on the management for incidental adnexal findings at CT and MRI. All three standardize reporting terminology, are based on evidence-based data and institutional practice patterns, and apply to nonpregnant women of average risk for ovarian cancer. While there are small differences in follow-up recommendations based on size thresholds, the goal of each is the same-to limit unnecessary imaging follow-up and, by doing so, save the patient time, money, and anxiety. For the diagnostic radiologist to use these guidelines, it is essential that the entire mass is visualized well. Without adequate visualization, further characterization of the mass may be necessary. To put it all together, the SRU consensus guideline and ACR white paper are easily applied in day-to-day practice for masses that are O-RADS 2 and below. An invited commentary by Patel is available online. The online slide presentation from the RSNA Annual Meeting is available for this article. ©RSNA, 2022.

Pearls and Pitfalls in Imaging of Pelvic Adnexal Torsion: Seven Tips to Tell It's Twisted.

Pelvic adnexal torsion is a collective term referring to twisting of an ovary, fallopian tube, or paraovarian cyst on its axis with varying degrees of vascular compromise. Although it is the fifth most common gynecologic emergency, the diagnosis is challenging and often missed due to symptoms, physical examination findings, and imaging features that are nonspecific. Delay in salvage surgery may lead to ovarian or tubal loss, dysfunction, and infertility. The tips shared herein are based on the authors' observations of key clinical and imaging features of torsion, with the intent of heightening radiologists' index of suspicion and diagnostic accuracy in a clear and memorable fashion. Clinically, severe acute pain with a known adnexal mass or of severity to elicit nausea or vomiting should raise concern. At imaging, features of ovarian edema are key to the diagnosis, including asymmetric ovarian enlargement, peripheralized follicles, adjacent free fluid, and foci of stromal hemorrhage. The converse finding of symmetric nonenlarged ovaries in a normal location with any imaging modality has a high negative predictive value for torsion, obviating the need for additional imaging. The whirlpool sign (twisted vascular pedicle), abnormal ovarian location, and uterine tilting are additional key imaging manifestations. The presence of color Doppler flow or contrast enhancement only suggests that an ovary is still viable and should not be used to exclude the diagnosis of torsion. In cases of isolated tubal or paraovarian cyst torsion, the ovaries may appear normal; therefore, recognition of this entity along with appreciation of several key imaging findings may assist with this difficult diagnosis. An invited commentary by Dighe is available online. Online supplemental material is available for this article. ©RSNA, 2021.

Acute (fulminant) liver failure: a clinical and imaging review.

Acute liver failure (ALF) is a rare clinical entity with high morbidity and mortality frequently requiring liver transplantation for survival. Imaging, particularly with ultrasound, plays an important role, especially to distinguish patients with underlying chronic liver disease who have lower transplant priority. We discuss the clinical and imaging findings in the three subtypes of ALF using a multi-modality approach with an emphasis on ultrasound.

Mapping the Ultrasound Landscape to Define Point-of-Care Ultrasound and Diagnostic Ultrasound: A Proposal From the Society of Radiologists in Ultrasound and ACR Commission on Ultrasound.

Current descriptions of ultrasound evaluations, including use of the term "point-of-care ultrasound" (POCUS), are imprecise because they are predicated on distinctions based on the device used to obtain images, the location where the images were obtained, the provider who obtained the images, or the focus of the examination. This is confusing because it does not account for more meaningful distinctions based on the setting, comprehensiveness, and completeness of the evaluation. In this article, the Society of Radiologists in Ultrasound and the members of the American College of Radiology Ultrasound Commission articulate a map of the ultrasound landscape that divides sonographic evaluations into four distinct categories on the basis of setting, comprehensiveness, and completeness. Details of this classification scheme are elaborated, including important clarifications regarding what ensures comprehensiveness and completeness. Practical implications of this framework for future research and reimbursement paradigms are highlighted.

Pitfalls in Renal Ultrasound.

Ultrasound (US) is replete with pitfalls in technique and interpretation, and renal imaging is no exception. Because US of the kidneys is a very common initial and follow-up imaging examination, it is important to be aware of both common and unusual sources of potential error. This essay will review optimal technique and discuss common overcalls, under calls, and misinterpretations with respect to renal size, hydronephrosis, calculi, cysts, masses, and collections.

Complications after Liver Transplant Related to Preexisting Conditions: Diagnosis, Treatment, and Prevention.

Diagnostic imaging after orthotopic liver transplant focuses primarily on depicting complications related to surgical hepatic vascular and biliary anastomoses. Less common preexisting vascular conditions include congenital anatomic variants, atherosclerosis, chronic portal venous thrombosis, splenic artery and variceal steal phenomena, and transarterial embolization (TAE) for hepatocellular carcinoma (HCC). If unappreciated or left untreated preoperatively, these conditions negatively impact the transplant by impairing hepatic arterial or portal vascular inflow. Many of the complications related to preexisting vascular conditions can be prevented or mitigated by proper performance and careful evaluation of preoperative imaging studies. The authors describe the diagnosis and treatment of complications arising from narrowing of the celiac axis by atherosclerosis and the median arcuate ligament, variant anatomy of the hepatic artery, insufficiency of the portal vein requiring surgical conduits, and large varices or an enlarged splenic artery and spleen that may steal blood and compromise hepatic arterial or venous inflow. While preoperative evaluation primarily involves CT and MRI, postoperative diagnosis involves screening with sonography and confirmation with other modalities. We propose the use of a preoperative checklist of vascular status and measurements in patients undergoing liver transplant. Reports of imaging studies in recipients after transplant should include details of surgical vascular anastomoses and conduits, any history of HCC and preoperative TAE, details of the preoperative α-fetoprotein levels, and any unusual procedures or pathologic findings in the explanted liver that may affect postoperative surveillance. The authors review the pretransplant imaging evaluation of vascular and HCC issues that may affect surgical outcomes and methods to help recognize complications after transplant that can arise from these conditions.©RSNA, 2020.

O-RADS US Risk Stratification and Management System: A Consensus Guideline from the ACR Ovarian-Adnexal Reporting and Data System Committee.

The Ovarian-Adnexal Reporting and Data System (O-RADS) US risk stratification and management system is designed to provide consistent interpretations, to decrease or eliminate ambiguity in US reports resulting in a higher probability of accuracy in assigning risk of malignancy to ovarian and other adnexal masses, and to provide a management recommendation for each risk category. It was developed by an international multidisciplinary committee sponsored by the American College of Radiology and applies the standardized reporting tool for US based on the 2018 published lexicon of the O-RADS US working group. For risk stratification, the O-RADS US system recommends six categories (O-RADS 0-5), incorporating the range of normal to high risk of malignancy. This unique system represents a collaboration between the pattern-based approach commonly used in North America and the widely used, European-based, algorithmic-style International Ovarian Tumor Analysis (IOTA) Assessment of Different Neoplasias in the Adnexa model system, a risk prediction model that has undergone successful prospective and external validation. The pattern approach relies on a subgroup of the most predictive descriptors in the lexicon based on a retrospective review of evidence prospectively obtained in the IOTA phase 1-3 prospective studies and other supporting studies that assist in differentiating management schemes in a variety of almost certainly benign lesions. With O-RADS US working group consensus, guidelines for management in the different risk categories are proposed. Both systems have been stratified to reach the same risk categories and management strategies regardless of which is initially used. At this time, O-RADS US is the only lexicon and classification system that encompasses all risk categories with their associated management schemes.

Management of Incidental Adnexal Findings on CT and MRI: A White Paper of the ACR Incidental Findings Committee.

The ACR Incidental Findings Committee (IFC) presents recommendations for managing adnexal masses incidentally detected on CT and MRI. These recommendations represent an update of those provided in our previous JACR 2013 white paper. The Adnexal Subcommittee, which included six radiologists with subspecialty expertise in abdominal imaging or ultrasound and one gynecologist, developed this algorithm. The recommendations draw from published evidence and expert opinion and were finalized by iterative consensus. Algorithm branches successively categorize adnexal masses based on patient characteristics (eg, pre- versus postmenopausal) and imaging features. They terminate with a management recommendation. The algorithm addresses most, but not all, pathologies and clinical scenarios. Our goal is to improve quality of care by providing guidance on how to manage incidentally detected adnexal masses.

Simple Adnexal Cysts: SRU Consensus Conference Update on Follow-up and Reporting.

This multidisciplinary consensus update aligns prior Society of Radiologists in Ultrasound (SRU) guidelines on simple adnexal cysts with recent large studies showing exceptionally low risk of cancer associated with simple adnexal cysts. Most small simple cysts do not require follow-up. For larger simple cysts or less well-characterized cysts, follow-up or second opinion US help to ensure that solid elements are not missed and are also useful for assessing growth of benign tumors. In postmenopausal women, reporting of simple cysts greater than 1 cm should be done to document their presence in the medical record, but such findings are common and follow-up is recommended only for simple cysts greater than 3-5 cm, with the higher 5-cm threshold reserved for simple cysts with excellent imaging characterization and documentation. For simple cysts in premenopausal women, these thresholds are 3 cm for reporting and greater than 5-7 cm for follow-up imaging. If a cyst is at least 10%-15% smaller at any time, then further follow-up is unnecessary. Stable simple cysts at initial follow-up may benefit from a follow-up at 2 years due to measurement variability that could mask growth. Simple cysts that grow are likely cystadenomas. If a previously suspected simple cyst demonstrates papillary projections or solid areas at follow-up, then the cyst should be described by using standardized terminology. These updated SRU consensus recommendations apply to asymptomatic patients and to those whose symptoms are not clearly attributable to the cyst. These recommendations can reassure physicians and patients regarding the benign nature of simple adnexal cysts after a diagnostic-quality US examination that allows for confident diagnosis of a simple cyst. Patients will benefit from less costly follow-up, less anxiety related to these simple cysts, and less surgery for benign lesions.

Ultrasound of the First Trimester.

Ultrasound is the imaging study of choice for detection and full characterization of early pregnancies based on its accuracy, low cost, safety profile, and abundant availability. This article reviews the goals and utility of first-trimester ultrasound in gestation localization, viability determination, and abnormal pregnancies, including ectopic implantation, retained products, and molar pregnancy.

Adenomyosis: A Sonographic Diagnosis.

Adenomyosis is a common benign uterine condition and a frequent cause of pelvic pain in premenopausal women. Transvaginal US is now considered the primary imaging modality for the diagnosis of adenomyosis, and thus radiologists should be familiar with its sonographic appearance. US findings can be divided into three categories, which parallel the histology of adenomyosis: (a) ectopic endometrial glands and stroma, (b) muscular hyperplasia/hypertrophy, and (c) increased vascularity. Ectopic endometrial glands manifest as echogenic nodules and striations, radiating from the endometrium into the myometrium. When the glands contain fluid, myometrial cysts and fluid-filled striations may be visible at US. Muscular hyperplasia and hypertrophy cause focal or diffuse myometrial thickening and globular uterine enlargement, often with thin "venetian blind" shadows. The combination of these findings results in a heterogeneous myometrium, with blurring of the endometrial border. Adenomyosis increases uterine vascularity, depicted as a pattern of penetrating vessels at color Doppler US. Other US techniques that are helpful in the diagnosis of adenomyosis include obtaining cine clips and coronal reformatted images, both of which can survey the entire endometrial-myometrial border, and performing saline-infusion sonohysterography, during which ectopic glands frequently fill with either air or fluid. While most cases of adenomyosis develop spontaneously, there are specific inciting causes that include tamoxifen use, postendometrial ablation syndrome, and deep-infiltrating endometriosis. Mimics of adenomyosis include leiomyomas, uterine contractions, neoplasms, and vascular malformations. This article reviews the pathophysiology of adenomyosis and correlates it with the US findings, highlights specific causes of adenomyosis, and describes how to distinguish this common diagnosis from a variety of mimics. Online supplemental material is available for this article. ©RSNA, 2018.

Ovarian-Adnexal Reporting Lexicon for Ultrasound: A White Paper of the ACR Ovarian-Adnexal Reporting and Data System Committee.

Ultrasound is the most commonly used imaging technique for the evaluation of ovarian and other adnexal lesions. The interpretation of sonographic findings is variable because of inconsistency in descriptor terminology used among reporting clinicians. The use of vague terms that are inconsistently applied can lead to significant differences in interpretation and subsequent management strategies. A committee was formed under the direction of the ACR initially to create a standardized lexicon for ovarian lesions with the goal of improving the quality and communication of imaging reports between ultrasound examiners and referring clinicians. The ultimate objective will be to apply the lexicon to a risk stratification classification for consistent follow-up and management in clinical practice. This white paper describes the consensus process in the creation of a standardized lexicon for ovarian and adnexal lesions and the resultant lexicon.