Ultrasound of palpable lesions: a pictorial review.

Ultrasound (US) is the imaging modality of choice for evaluation of superficial palpable lesions. A large proportion of these lesions have characteristic sonographic appearance and can be confidently diagnosed with US without the need for biopsy or other intervention. The Society of Radiologists in Ultrasound (SRU) recently published a Consensus Conference Statement on superficial soft tissue masses. The goal of this manuscript is (a) to serve as a sonographic pictorial review for palpable lesions based on the SRU statement, (b) present the typical sonographic features of palpable lesions that can be confidently diagnosed with US, and (c) provide an overview of other palpable lesions with a framework to interpret the US studies and advise on appropriate further management.

O-RADS US v2022: An Update from the American College of Radiology's Ovarian-Adnexal Reporting and Data System US Committee.

First published in 2019, the Ovarian-Adnexal Reporting and Data System (O-RADS) US provides a standardized lexicon for ovarian and adnexal lesions, enables stratification of these lesions with use of a numeric score based on morphologic features to indicate the risk of malignancy, and offers management guidance. This risk stratification system has subsequently been validated in retrospective studies and has yielded good interreader concordance, even with users of different levels of expertise. As use of the system increased, it was recognized that an update was needed to address certain clinical challenges, clarify recommendations, and incorporate emerging data from validation studies. Additional morphologic features that favor benignity, such as the bilocular feature for cysts without solid components and shadowing for solid lesions with smooth contours, were added to O-RADS US for optimal risk-appropriate scoring. As O-RADS US 4 has been shown to be an appropriate cutoff for malignancy, it is now recommended that lower-risk O-RADS US 3 lesions be followed with US if not excised. For solid lesions and cystic lesions with solid components, further characterization with MRI is now emphasized as a supplemental evaluation method, as MRI may provide higher specificity. This statement summarizes the updates to the governing concepts, lexicon terminology and assessment categories, and management recommendations found in the 2022 version of O-RADS US.

Placenta Accreta Spectrum Disorders: Update and Pictorial Review of the SAR-ESUR Joint Consensus Statement for MRI.

Placenta accreta spectrum (PAS) disorders are a major cause of maternal morbidity and mortality and are increasing in incidence owing to a rising rate of cesarean delivery. US is the primary imaging tool for evaluation of PAS disorders, which are most often diagnosed during routine early second-trimester US to assess fetal anatomy. MRI serves as a complementary modality, providing value when the diagnosis is equivocal at US and evaluating the extent and topography of myoinvasion for surgical planning in severe cases. While the definitive diagnosis is established by a combined clinical and histopathologic classification at delivery, accurate antenatal diagnosis and multidisciplinary management are critical to guide treatment and ensure optimal outcomes for these patients. Many MRI features of PAS disorders have been described in the literature. To standardize assessment at MRI, the Society of Abdominal Radiology (SAR) and European Society of Urogenital Radiology (ESUR) released a joint consensus statement to provide guidance for image acquisition, image interpretation, and reporting of PAS disorders. The authors review the role of imaging in diagnosis of PAS disorders, describe the SAR-ESUR consensus statement with a pictorial review of the seven major MRI features recommended for use in diagnosis of PAS disorders, and discuss management of these patients. Familiarity with the spectrum of MRI findings of PAS disorders will provide the radiologist with the tools needed to more accurately diagnose this disease and make a greater impact on the care of these patients. ©RSNA, 2023 Supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center. See the invited commentary by Jha and Lyell in this issue.

The Ovarian/Adnexal Reporting and Data System for Ultrasound: From Standardized Terminology to Optimal Risk Assessment and Management.

The American College of Radiology (ACR) Ovarian-Adnexal Reporting and Data System (O-RADS) lexicon and risk assessment tool for ultrasound (US) provides a framework for characterization of ovarian and adnexal pathology with the ultimate goal of harmonizing reporting and patient management strategies. Since the first O-RADS US publication in 2018, multiple validation studies have shown O-RADS US to have excellent diagnostic accuracy, with the majority of these studies using O-RADS 4 as the optimal cut-off for detecting ovarian cancer. Most of the existing validation studies include a dedicated training phase and confirm that ORADS US categories and lexicon descriptors are associated with high level inter-read agreement, regardless of radiologist training level or practice experience. O-RADS US has a similar inter-reader agreement when compared to Gynecologic Imaging Reporting and Data System (GIRADS), Assessment of Different Neoplasias in the adnexa (ADNEX), and International Tumor Analysis Group (IOTA) simple rules. System descriptors have been shown to correlate with expected malignancy rates and the O-RADS US risk stratification system has been shown to perform in the expected range of malignancy risk per category. Further directions will focus on clarifying governing concepts and lexicon terminology as well as further refining risk stratification categories based on data from published validation studies.

Interreader Agreement and Intermodality Concordance of O-RADS US and MRI for Assessing Large, Complex Ovarian-Adnexal Cysts.

Purpose To assess interreader agreement of the Ovarian-Adnexal Reporting and Data System (O-RADS) and intermodality concordance between US and MRI for characterizing complex adnexal cysts measuring 5 cm or larger. Materials and Methods This retrospective study included 58 "complex cysts" measuring at least 5 cm in size observed at both US and MRI in 54 women (median age, 37 years ± 12 [SD]; seven postmenopausal women) between July 2017 and June 2020, identified from an electronic US database. A separate set of two blinded radiologists independently reviewed the US or MR images to assign the O-RADS category, and an adjudicator resolved discrepancies (a total of six readers). Lesion outcome (49 benign, eight malignant, one lost to follow-up) was recorded. Interreader agreement of O-RADS US and O-RADS MRI and concordance between US and MRI were analyzed. Results Interreader agreement was fair for US (κ = 0.31), moderate for MRI (κ = 0.43), and moderate between US and MRI (κ = 0.58). A significant positive correlation was found between O-RADS US and MRI (τ = 0.72, P < .001). The O-RADS 4 threshold yielded the highest accuracy for both US and MRI (area under the receiver operating characteristic curve = 0.92 and 0.995, respectively). Considering O-RADS US 4 or 5 as potentially malignant and 1-3 as benign, eight lesions that were assessed as potentially malignant at US were correctly downgraded to benign by using findings at MRI. Using findings at MRI, one malignant lesion that was assessed as benign at US was upgraded to potentially malignant. Conclusion O-RADS US and MRI had excellent performance and positive correlation, but significant interobserver variability remains. Keywords: Ovary, MR Imaging, Ultrasonography © RSNA, 2022 See also the commentary by Baumgarten in this issue.

Fourfold Improved Odds of a Good First Trimester Outcome Once a Yolk Sac Is Seen in Early Pregnancy.

OBJECTIVES: To compare first trimester prognosis when an early pregnancy sonogram demonstrates a gestational sac with yolk sac versus gestational sac without yolk sac. METHODS: Our study comprised 823 transvaginal sonograms without identifiable embryo performed at least 35 days from last menstrual period (LMP), in which mean sac diameter was <16 mm and first trimester outcome (live or early pregnancy loss) was known. We recorded the presence or absence of yolk sac, first trimester outcome, and several clinical features: maternal age, time since LMP, and presence or absence of vaginal bleeding. We compared the likelihood of a successful first trimester outcome in cases with a visible yolk sac to those without a yolk sac. RESULTS: At the end of the first trimester, 113 of 270 (41.9%) cases without a yolk sac and 414 of 553 (74.9%) with a yolk sac were live (P < .000001, chi-square). This corresponds to an odds ratio of 4.14 for the presence of yolk sac, a result confirmed by logistic regression. Advanced maternal age, ≥42 days since LMP, and vaginal bleeding all carried an increased risk of loss (P < .000001, chi-square). Outcome was better with a visualized yolk sac than without a yolk sac, regardless of number of risk factors (P < .001, chi-square). CONCLUSIONS: The odds of successful first trimester outcome are 4-fold higher when a yolk sac is seen on an early pregnancy sonogram than when no yolk sac is seen. For any level of risk, based on maternal age, vaginal bleeding, and time since LMP, outcome is significantly better when a yolk sac is seen.

First-Trimester Prognosis When an Early Gestational Sac is Seen on Ultrasound Imaging: Logistic Regression Prediction Model.

OBJECTIVES: To determine the factors that jointly and independently affect first-trimester outcome of very early intrauterine pregnancies (those whose sonogram shows a gestational sac with no identifiable yolk sac or embryo) and develop a mathematical model and Web-based calculator that computes prognosis based on these factors. METHODS: Our study population included 590 very early pregnancies scanned between January 1, 2012, and June 30, 2018, with known outcomes (live or spontaneous loss) at 14 weeks. We recorded patient age, mean sac diameter (MSD), human chorionic gonadotropin (hCG) rise, and presence/absence of: vaginal bleeding, history of infertility, prior miscarriage, and pregnancy via assisted reproductive technology. We assessed the correlation between each of these factors and outcome and performed stepwise logistic regression to determine the subset that independently correlated with outcome. RESULTS: Patient age, MSD, hCG rise, vaginal bleeding, history of infertility, and assisted reproductive technology pregnancy were significantly correlated with outcome (P < .05, t test for age and MSD, χ2 for the others). Stepwise logistic regression identified age, MSD, hCG rise, and vaginal bleeding as the subset of factors that independently predicted outcome. The regression model's area under the receiver operating characteristic curve was 0.823. We incorporated the regression model into a Web-based calculator (https://tinyurl.com/Prognosis-PD) that predicts the outcome of an early intrauterine pregnancy based on these 4 key variables. CONCLUSIONS: The prognosis of very early intrauterine pregnancies is related to several clinical, biochemical, and sonographic factors. The factors that independently correlate with first-trimester outcome are patient age, MSD, hCG rise, and vaginal bleeding. The logistic regression model predicts outcome based on these variables.

Clinical Significance of Renal Allograft Urothelial Thickening Identified by Ultrasound.

OBJECTIVES: To assess the etiology and clinical implications of ultrasound (US)-diagnosed urothelial thickening (UT) in renal transplants. METHODS: Patients with renal transplants who had UT diagnosed by US from January 2000 to December 2018 were retrospectively identified and compared to patients with transplants without UT scanned during the study period. Medical records were reviewed for demographics, US findings, pathologic results, laboratory values, and clinical outcomes and compared between groups by Fisher exact and t tests. RESULTS: A total of 143 patients with UT and 128 controls comprised our cohorts. The patient age in the UT group versus controls (mean ± SD, 50.2 ± 16.5 versus 51.2 ± 15.3 years) and the time since transplant (2.9 ± 4.2 versus 2.4 ± 5.8 years) were similar. Patients with UT were more likely to be female than controls (76 of 143 [53.1%] versus 53 of 128 [41.4%]; P = .07), but the difference was not statistically significant, and patients with UT were more likely to have indwelling stents (31 of 143 [21.7%] versus 9 of 128 [7.0%]; P = .001) and hydronephrosis (25 of 143 [17.4%] versus 11 of 128 [8.6%]; P = .03). At biopsy, rejection and vascular sclerosis were more likely in patients with UT compared to controls (24 of 25 [49.0%] versus 11 of 43 [25.6%]; P = .031; 42 of 49 [85.7%] versus 22 of 43 [51.2%]; P = .0005, respectively), whereas acute tubular necrosis was similar. The sensitivity (50.0%) and specificity (74.4%) of UT for rejection were low. CONCLUSIONS: Urothelial thickening correlates with US findings of urinary obstruction and indwelling stents, suggesting a possible mechanical component to UT's etiology. Although transplant rejection and vascular sclerosis were more frequent at biopsy in the UT group than controls, UT had low sensitivity and specificity for rejection.

"Pseudogestational Sac" and Other 1980s-Era Concepts in Early First-Trimester Ultrasound: Are They Still Relevant Today?

OBJECTIVES: To determine whether an intrauterine round or oval fluid collection ("saclike structure") can prove to be either an intrauterine pregnancy or intrauterine fluid in conjunction with an ectopic pregnancy (sometimes termed "pseudogestational sac") and whether ultrasound features, including the presence or absence of an echogenic rim, "double sac sign" (DSS), or "intradecidual sign" (IDS), are helpful for establishing the diagnosis or predicting the prognosis. METHODS: We identified all sonograms obtained from women with positive serum human chorionic gonadotropin results at our institution between January 1, 2012, and June 30, 2018, meeting the following criteria: presence of an intrauterine saclike structure without a yolk sac or embryo; no extraovarian adnexal mass; and follow-up information identifying the location of the pregnancy as intrauterine or ectopic. Study authors reviewed sonograms in all cases and recorded the following information: presence or absence of each of an echogenic rim around the collection, a DSS, and an IDS, as well as the mean sac diameter. The indications for the initial ultrasound examinations were recorded. RESULTS: A total of 649 sonograms met the inclusion criteria. Of these, 598 fluid collections showed an echogenic rim, 182 a DSS, and 347 an IDS (findings not mutually exclusive). In all 649 cases, a subsequent sonogram or other clinical follow-up confirmed that the patient had an intrauterine pregnancy. That is, none of the fluid collections proved to be a pseudogestational sac. In total, 41.2% were live at the end of the first trimester, and 58.8% miscarried. The prognosis was better in cases with, compared to without, an IDS (P = .01, χ2 ), but no ultrasound feature was clinically useful for ruling in or excluding a good prognosis. CONCLUSIONS: In a woman with positive human chorionic gonadotropin results and no extraovarian adnexal mass, the ultrasound finding of an intrauterine saclike structure is virtually certain to be a gestational sac. Ultrasound features of the structure are of no diagnostic or clinically useful prognostic value. Concepts introduced 30 to 40 years ago when ultrasound equipment had far lower resolution than currently, including a DDS, an IDS, and a pseudogestational sac, have no role today in assessing early pregnancy.

Radiologic Findings in Intimate Partner Violence.

Purpose To assess the radiologic findings associated with intimate partner violence (IPV). Materials and Methods Electronic medical records of 185 patients referred to the IPV support program from the emergency department (ED) between January 2015 and October 2016 were retrospectively reviewed and compared with an age- and sex-matched control group of 555 subjects (1:3 ratio of IPV victims to control subjects) who presented to the ED. Reports of all imaging studies performed within 5 years prior to the index ED visit were reviewed. Results The majority of patients who experienced IPV (mean age, 34.2 years ± 12.2 [standard deviation]) were female (178 of 185 [96.2%]) and were largely African American (69 of 185 [37.3%]). Demographic and clinical variables independently associated with IPV were race (odds ratio [OR] range, 3.2-5.9; 95% confidence interval [CI]: 1.8, 12.7), psychiatric comorbidities (OR, 5.4; 95% CI: 3.4, 8.8), and homelessness (OR, 13.0; 95% CI: 5.4, 31.2). IPV victims underwent more imaging studies in the preceding 5 years (median, four studies) than did control subjects (median, one study). Obstetric-gynecologic findings (OR, 4.4; 95% CI: 2.1, 9.6) and acute fractures (OR, 2.4, 95% CI: 1.1, 5.3) seen on images were independently associated with IPV. The addition of imaging findings to demographic and clinical variables increased the area under the receiver operating characteristic curve (AUC) of the multivariate model to detect IPV (0.87 vs 0.86, P < .01), and the cross-validated multivariate model had an AUC of 0.85. Acute fractures involved the face or skull (range, P < .01 to P = .05), and chronic fractures affected the extremities and nasal bone (P < .01 and P = .05, respectively) more frequently in the IPV group than in the control group. Conclusion Intimate partner violence victims undergo more imaging studies and have a higher frequency of potential violence-related imaging findings when compared with age- and sex-matched control subjects. © RSNA, 2019 See also the editorial by Flores and Narayan in this issue.

Customized Residency Leadership Tracks: A Review of What Works, What We're Doing and Ideas for the Future.

Effective leaders are essential to ensure the future of radiology. Radiologists often find themselves in leadership positions despite a lack of formal leadership training. The fourth year of residency is the ideal time to expose young physicians to leadership and extraclinical specialization, as such leadership development prior to fellowship may still impact academic career choice. In this manuscript, we discuss prior successes of leadership tracks within medicine and review the evidence supporting the saying that "leaders are made, not born". Finally, we describe the evolution of our institution's residency leadership tracks highlighting key components, challenges, early successes and future endeavors.

First-trimester emergencies: a radiologist's perspective.

The purpose of this article is to help the practitioner ensure early diagnosis and response to emergencies in the first trimester by reviewing anatomy of the developing embryo, highlighting the sonographic appearance of common first-trimester emergencies, and discussing key management pathways for treating emergent cases. First-trimester fetal development is a stepwise process that can be challenging to evaluate in the emergency department (ED) setting. This is due, in part, to the complex anatomy of early pregnancy, subtlety of the sonographic findings, and the fact that fewer than half of patients with ectopic pregnancy present with the classic clinical findings of a positive pregnancy test, vaginal bleeding, pelvic pain, and tender adnexa. Ultrasound (US) has been the primary approach to diagnostic imaging of first-trimester emergencies, with magnetic resonance imaging (MRI) and computed tomography (CT) playing a supportive role in a small minority of cases. Familiarity with the sonographic findings diagnostic of and suspicious for early pregnancy failure, ectopic pregnancy, retained products of conception, gestational trophoblastic disease, failed intrauterine devices, and complications associated with assisted reproductive technology (ART) is critical for any emergency radiologist. Evaluation of first-trimester emergencies is challenging, and knowledge of key imaging findings and familiarity with management pathways are needed to ensure early diagnosis and response.

Ovary-Sparing Radiation Planning Techniques Can Achieve Ovarian Dose Reduction for Soft Tissue Sarcoma of the Buttock and Thigh.

BACKGROUND AND OBJECTIVES: Attention to ovary dose is important for premenopausal women undergoing radiation therapy (RT) and must not be overlooked when treating extremity sarcoma. We assessed whether ovary-sparing RT plans could decrease ovary dose without compromising target coverage. METHODS: Standard sarcoma target volumes and organs at risk (OAR) were contoured by a sarcoma dedicated radiation oncologist on CT planning scans for 23 women with thigh or buttock sarcoma. IMRT plans (50 Gy) with and without attempted ovary-sparing were created by an expert sarcoma dosimetrist. RESULTS: All plans met target coverage goals. Compared to standard plans, ovary-sparing plans had lower mean bilateral ovary doses (MBOD) (652 versus 483 cGy, p = 0.007) but higher bone doses (mean V50: 8.5% versus 6.9%, p = 0.049) and lower conformity indexes (1.12 versus 1.19, p = 0.009). Tumors < 8 cm from the pubic symphysis had significant MBOD reduction with ovary-sparing plans (376 cGy versus 619 cGy, p = 0.0184). On multivariate analysis, distance to pubic symphysis and proximal medial thigh site were associated with MBOD reduction with ovary-sparing plan. CONCLUSIONS: For preoperative IMRT, ovary-sparing planning significantly reduces ovarian dose in women with sarcoma of the proximal thigh and near the pubic symphysis.

Update on the imaging of malignant perivascular epithelioid cell tumors (PEComas).

Malignant perivascular epithelioid cell tumors (PEComas) are a histologic group of mesenchymal neoplasms that share a distinctive histological phenotype, the perivascular epithelioid cell. These tumors are known for their perivascular distribution. Malignant PEComas have a female predominance and are associated with aggressive disease and poor prognosis, making timely diagnosis critical to management. Imaging features of malignant PEComas are nonspecific and mimic other benign and malignant neoplasms. Surgery is the mainstay in the management of malignant PEComas. Promising novel molecular targeted therapies like m-TOR inhibitors have been shown to be effective in the metastatic setting. The aim of this review is to familiarize radiologists with the imaging appearances of and potential therapies for primary and metastatic malignant PEComa.