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.

Thyroid Nodule Margin Assessment Using ACR TI-RADS: Adding Points for Macrolobulation Impairs Performance.

OBJECTIVE: We evaluated the performance of ACR TI-RADS when points for lobulated margins are applied only when the margins meet a quantified measure of margin microlobulation and not applied when nodules only demonstrate macrolobulation. METHODS: We retrospectively reviewed ultrasound and pathology records (May 01, 2018 to July 31, 2020) to find all thyroid nodules at one institution characterized as having lobulated margins using the ACR TI-RADS lexicon and subsequently undergoing fine needle aspiration (FNA). Nodule margins were evaluated to note the presence or absence of microlobulation, quantitatively defined as a protrusion with a base <2.5 mm in length. The impact to detection of malignant nodules and avoidance of benign FNA when margin points for lobulation were added only when microlobulated was analyzed. RESULTS: 58 of 516 thyroid nodules undergoing US-guided FNA were classified as lobulated, comprising the study population. 21 (36.2%) had microlobulated margins, with 12 of the 21 (57.1%) being malignant. Comparatively, of the 37 nodules showing only macrolobulated margins without microlobulation, only 2 (5.4%) were malignant (P < .0001). For 53 nodules ≥10 mm, 15 (28.3%) benign nodules would not have met size criteria for FNA had points for margins not been applied when only showing macrolobulation, whereas all 10 malignant nodules would still have been sampled. CONCLUSION: Adding two points to the ACR TI-RADS score for lobulated thyroid nodules should only apply when microlobulations are present.

Varicose Veins of the Lower Extremity: Doppler US Evaluation Protocols, Patterns, and Pitfalls.

Venous insufficiency is a cause of substantial morbidity and medical expenditures. Diagnostic US evaluation of venous insufficiency requires a thorough understanding of the venous anatomy, including the deep, superficial, and perforator veins. The highly variable venous anatomy requires that operators use sound judgment to expand on protocol images and thus avoid missing important sources of reflux. The US examination requires specific patient positioning and use of provocative maneuvers. A basic understanding of the pathophysiology of venous insufficiency and the various treatment methods helps to identify key observations so that ineffective treatment methods are not pursued. The examination reports should have greater detail than those for the more common lower extremity deep venous thrombosis evaluation, requiring numeric and narrative descriptions of deep and superficial venous patency, reflux, diameter, and pathways. Potential pitfalls include not recognizing or detecting deep venous reflux, misidentifying common femoral vein reflux as deep venous reflux when the reflux is isolated or related to saphenofemoral insufficiency, not recognizing anterior accessory great saphenous vein (AAGSV) involvement in saphenofemoral insufficiency, not recognizing or reporting great saphenous vein or AAGSV superficialization, not suspecting central venous obstruction, and not realizing when provocative maneuvers were ineffective. With knowledge of the lower extremity venous anatomy, venous insufficiency pathophysiology, basic treatment strategies, protocol best practices, patterns of observation, and diagnostic pitfalls, those who interpret venous insufficiency US studies can perform examinations and deliver reports that help patients receive appropriate treatment. Online supplemental material is available for this article. ©RSNA, 2022.

Non-Vascular Considerations When Interpreting Extremity Arterial and Venous Examinations.

Peripheral arterial and venous examinations are performed regularly in vascular labs and interpreted by physicians of different specialities. Many vascular examinations have nonvascular pathology that is either inadvertently imaged by the sonographer or imaged with intent as it relates to patient's symptoms. It is prudent for every reader of vascular studies to be acquainted with the sonographic appearance of these non-vascular lesions to enable appropriate and optimal interpretation that has a direct bearing on patient's clinical care. Our review includes a discussion of the nonvascular pathologies like lymph nodes, soft tissue edema, soft tissue fluid collections, musculotendinous injuries, soft tissue masses, and joint and bursal pathologies that may be encountered during interpretation of vascular exams. The pictorial essay includes a discussion of their sonographic appearances and pitfalls in interpretation. Multiple illustrative examples and sonographic images of the non-vascular pathologies found during interpretation of vascular studies have been utilized to highlight their appearances.

Detection of Bleeding Complications After Renal Transplant Biopsy.

OBJECTIVE. The purpose of this study was to analyze the timing of major bleeding complications after renal transplant biopsy in the context of a standardized 1-hour postprocedure observation protocol. MATERIALS AND METHODS. We retrospectively reviewed the electronic medical records for consecutive patients who underwent ultrasound-guided renal transplant biopsies between January 1, 2012, and December 31, 2017, and were observed according to a newly implemented 1-hour postprocedure observation protocol. The development of a major bleeding complication (Common Terminology Criteria for Adverse Events class 3 or higher) was recorded along with all available details regarding the time course of patient symptoms and presentation. Complications were grouped into one of four categories according to onset time after biopsy: 2 hours or less (timing category 1), more than 2 hours but 4 hours or less (timing category 2), more than 4 hours but 8 hours or less (timing category 3), and more than 8 hours (timing category 4). RESULTS. In 1824 patients (769 women, 1055 men) who underwent 4519 consecutive ultrasound-guided renal transplant biopsies during the study period, 11 class 3 complications were found (11/4519 [0.2%]). Four of the 11 patients (36.4%) had symptoms during the 1-hour observation period. Of these four patients, three (3/11 [27.3%]) had substantial symptoms related to major bleeding and were classified as timing category 1, and one (1/11 [9.1%]) had initially minor symptoms that increased in severity more than 2 hours but within 4 hours and was classified as timing category 2. Seven of the 11 patients (63.6%) did not have any symptoms at 1 hour of observation and were discharged; three (27.3%) were classified as timing category 3, and four (36.4%) were classified as category 4. CONCLUSION. Major bleeding complications following ultrasound-guided renal transplant biopsy are rare (0.2% of patients in this study). In our study, more than half were not clinically apparent within 4 hours of biopsy. A 1-hour postprocedure recovery period can be safely used after renal transplant biopsy.

The Flipped Ovary Sign in Ovarian Torsion.

The diagnosis of ovarian torsion is challenging and relies mostly on morphologic findings. Occasionally, women or children with acute pelvic pain who have undergone an initial ultrasound (US) evaluation with results interpreted as negative for ovarian torsion will return with recurrent or increasing pain, prompting an US reevaluation. The flipped ovary sign refers to a demonstrable change in the orientation of the ovary on follow-up US examinations, recognized by changing positions of ovarian landmarks established by follicles, cysts, or masses. This sign is valuable for identifying ovarian torsion in these patients, even in the absence of classic morphologic or Doppler features of ovarian torsion.

Growth Rate of Ovarian Serous Cystadenomas and Cystadenofibromas.

OBJECTIVES: We analyzed growth rates of benign ovarian serous cystadenomas and cystadenofibromas to understand what percentage would show a volume doubling time (DT) of less than 3 years, between 3 and 5 years, or greater than 5 years. METHODS: We retrospectively reviewed pathology records (January 1, 2014, to June 30, 2019) to find all surgically excised ovarian serous cystadenomas and cystadenofibromas. Imaging records were then reviewed to identify those that had been confidently identified with ultrasound imaging, magnetic resonance imaging, or computed tomography at least twice before surgical removal, with at least a 60-day interval between studies. Three orthogonal measurements were recorded on the first and last imaging studies on which the mass was detected, with volume calculations by the prolate formula (product of 3 measurements multiplied by 0.52). The volume DT was calculated and grouped into 1 of 5 categories: (1) DT of less than 1 year; (2) DT of 1 to 3 years; (3) DT of 3 to 5 years; (4) DT of 5 to 10 years; and (5) no growth (any mass with a DT >10 years or showing a decrease in volume). RESULTS: A total of 102 of 536 cystadenomas and 44 of 227 cystadenofibromas met inclusion criteria. Of the 146 tumors, 40 (27.4%) had a DT of less than 1 year; 38 (26.0%) had a DT of 1 to 3 years; 22 (15.1%) had a DT of 3 to 5 years; 10 (6.8%) had a DT of 5 to 10 years; and 36 (24.7%) showed no growth. CONCLUSIONS: A total of 53.4% of ovarian serous cystadenomas/cystadenofibromas have a DT of less than 3 years; 15.1% have a DT between 3 and 5 years; and 31.5% have a DT of greater than 5 years or show no growth.

Impact of Uterine Sliding Sign in Routine United States Ultrasound Practice.

OBJECTIVES: The study aim was to evaluate the diagnostic performance of the uterine sliding sign in predicting deeply infiltrating endometriosis in the setting of non-physician sonographers performing but not interpreting the maneuver. The impact of uterine sliding sign has not been previously demonstrated in this practice setting. METHODS: Physicians' remote interpretations of transvaginal ultrasound examinations in 2016, before uterine sliding sign, were compared to examinations in 2019 after addition of uterine sliding sign to determine the diagnostic rates. Surgical and histopathological results were reviewed to determine sensitivity and specificity of the respective exam techniques. RESULTS: Two hundred eighty-five transvaginal ultrasounds were performed in 2016 and 390 sliding sign ultrasounds in 2019. The number of deeply infiltrating endometriosis cases identified increased significantly from 2% to 6% during the study period (chi-square, Fisher's exact test p = .012). The sensitivity and specificity of routine pelvic sonography for detecting deeply infiltrating endometriosis improved from 36%/94% to 68%/98%. CONCLUSIONS: Uterine sliding sign videos should be included in the standard sonographic protocol for patients presenting with chronic pelvic pain, endometriosis history, or sonographic evidence of endometriosis in the setting of physicians interpreting sonographic images obtained by non-physicians.

Added Benefit and Risk of an Additional Biopsy or Targeting With Contrast-Enhanced Ultrasound for Patients With Renal Transplants.

OBJECTIVES: To determine whether renal transplant diagnoses substantially change when 2 biopsy sites are chosen and whether contrast-enhanced ultrasound (CEUS) has value for targeting the second site. METHODS: We prospectively enrolled 40 patients undergoing ultrasound-guided renal transplant biopsy within 2 years of transplant: 20, surveillance; and 20, for cause. A CEUS examination was performed to identify cortical regions with subjectively altered flow. One biopsy was performed at the operator-preferred (primary) site regardless of CEUS findings. Another biopsy was done at a second location, either targeted to an area in which CEUS perfusion findings differed from the primary site (targeted) or at a random location (secondary) if no other area differed. Specimens were randomly labeled A or B; pathologists were blinded to the CEUS result and biopsy location. Location-specific CEUS assessments were recorded. Pathologic results were compared, including acute and chronic Banff scores and any new findings from the targeted or secondary biopsy. RESULTS: Forty patients were enrolled between January 2016 and December 2018. No location-specific pathologic differences correlated with differences in CEUS assessments. The second biopsy provided additional information that changed management in 4 of 40 patients (10.0% [95% confidence interval, 2.8%-23.7%]). Major bleeding complications occurred in 3 of 40 (7.5%) patients. CONCLUSIONS: Contrast-enhanced ultrasound targeting was not useful. Major bleeding complications were higher than expected, possibly due to the additional biopsy away from the operator-preferred location. Obtaining a second renal transplant biopsy from a substantially different area than the initial operator-preferred location provided additional clinically useful information in 10% of patients.

Radiologists Make More Errors Interpreting Off-Hours Body CT Studies during Overnight Assignments as Compared with Daytime Assignments.

Background There is increasing research attention on the impact of overnight work on radiologist performance. Prior studies on overnight imaging interpretive errors have focused on radiology residents, not on the relative performance of board-eligible or board-certified radiologists at night compared with during the day. Purpose To analyze the rate of clinically important interpretation errors on CT examinations of the abdomen, pelvis, or both ("body CT studies") committed by radiology fellows working off-hours based on day or night assignment. Materials and Methods Between July 2014 and June 2018, attending physicians at one tertiary care institution reviewed all body CT studies independently interpreted off-hours by radiologists in an academic fellowship within 10 hours of initial interpretation. Discrepancies affecting acute or follow-up clinical care were classified as errors. In this retrospective study, the error rate for studies interpreted during the day (between 7:00 am and 5:59 pm) was compared with that of studies interpreted at night (between 6:00 pm and 6:59 am). Error rate in the first half of day and night assignments was compared with error rate in the latter half. Statistical analyses used χ2 tests and general estimating equations; significance was defined as P < .05. Results There were 10 090 body CT studies interpreted by 32 radiologists. Forty-four of 2195 daytime studies (2.0%) had errors compared with 240 of 7895 nighttime studies (3.0%; P = .02). Twenty-two of 32 (69%) radiologists had higher error rates for night cases (P = .03). There were more errors in the last half of a night assignment (125 of 3358, 3.7%; P = .002) compared with the first half (115 of 4537, 2.5%). Conclusion On the basis of a subspecialty review, clinically important off-hours body CT interpretation errors occurred more frequently overnight and more frequently in the latter half of assignments, with more radiologists having worse error rates at night compared with the day. © RSNA, 2020 See also the editorial by Bruno in this issue.

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.

Initial Accuracy of and Learning Curve for Transvaginal Ultrasound with Bowel Preparation for Deep Endometriosis in a US Tertiary Care Center.

STUDY OBJECTIVE: To evaluate the diagnostic accuracy and learning curve of a sonographic mapping protocol for deep endometriosis (DE). DESIGN: Retrospective cohort study (Canadian Task Force classification II-3). SETTING: Tertiary referral center in the United States. PATIENTS: 117 consecutive patients who presented to our gynecology clinic with complaints of significant noncyclic pelvic pain of at least 6 months' duration, and/or clinical findings concerning for deep endometriosis and who were referred for transvaginal ultrasound with bowel preparation. INTERVENTIONS: Patients underwent transvaginal ultrasound with bowel-preparation (TVUS-BP) performed by a single radiologist. Findings suspicious for DE were reported and correlated with surgical and histopathological findings. The duration of the examination and number of cases required to achieve proficiency were calculated for positive, equivocal, and negative findings. MEASUREMENTS AND MAIN RESULTS: Among 117 patients (median age, 35 years; range, 19-54 years) referred for TVUS-BP, 113 had complete examinations. Fifty-seven of these 113 patients underwent surgical exploration within 1 year, and DE was identified surgically in 23 of them. DE of the rectosigmoid colon and/or rectovaginal septum was detected with a sensitivity of 94% (95% confidence interval [CI], 70%-100%) and specificity of 100% (95% CI, 91%-100%). DE of the retrocervical region and/or uterosacral ligaments was detected with a sensitivity of 86% (95% CI, 65%-97%) and specificity of 94% (95% CI, 81%-99%). Proficiency, defined by a flattening of the learning curve, was achieved after 70 to 75 scans. The mean duration of the examination was 42 ± 4 minutes initially, but declined to 15 ± 4 minutes once proficiency was achieved. Cases of equivocal or minimal disease demonstrated the greatest decline in examination duration. CONCLUSION: A newly applied TVUS-BP protocol for detection of pelvic DE is highly accurate and required only a modest learning curve to achieve procedural proficiency in a US tertiary referral center where physicians interpret but typically do not perform TVUS exams. Overcoming diagnostic uncertainty regarding minimal or equivocal disease appeared to be an important factor in the initial learning curve. With adequate training, TVUS-BP may be adapted as a primary diagnostic tool for detecting pelvic DE.

Integrated genomic characterization reveals novel, therapeutically relevant drug targets in FGFR and EGFR pathways in sporadic intrahepatic cholangiocarcinoma.

Advanced cholangiocarcinoma continues to harbor a difficult prognosis and therapeutic options have been limited. During the course of a clinical trial of whole genomic sequencing seeking druggable targets, we examined six patients with advanced cholangiocarcinoma. Integrated genome-wide and whole transcriptome sequence analyses were performed on tumors from six patients with advanced, sporadic intrahepatic cholangiocarcinoma (SIC) to identify potential therapeutically actionable events. Among the somatic events captured in our analysis, we uncovered two novel therapeutically relevant genomic contexts that when acted upon, resulted in preliminary evidence of anti-tumor activity. Genome-wide structural analysis of sequence data revealed recurrent translocation events involving the FGFR2 locus in three of six assessed patients. These observations and supporting evidence triggered the use of FGFR inhibitors in these patients. In one example, preliminary anti-tumor activity of pazopanib (in vitro FGFR2 IC50≈350 nM) was noted in a patient with an FGFR2-TACC3 fusion. After progression on pazopanib, the same patient also had stable disease on ponatinib, a pan-FGFR inhibitor (in vitro, FGFR2 IC50≈8 nM). In an independent non-FGFR2 translocation patient, exome and transcriptome analysis revealed an allele specific somatic nonsense mutation (E384X) in ERRFI1, a direct negative regulator of EGFR activation. Rapid and robust disease regression was noted in this ERRFI1 inactivated tumor when treated with erlotinib, an EGFR kinase inhibitor. FGFR2 fusions and ERRFI mutations may represent novel targets in sporadic intrahepatic cholangiocarcinoma and trials should be characterized in larger cohorts of patients with these aberrations.

Factors Contributing to the Success of Ultrasound-Guided Native Renal Biopsy.

OBJECTIVES: The purpose of this study was to evaluate factors contributing to the success of ultrasound-guided native renal biopsy. METHODS: We retrospectively identified patients who had ultrasound-guided native renal biopsy at our institution over a 10-year period. We reviewed the imaging and electronic medical records to collect demographic information and clinical data, including pathologic results. Biopsy samples were categorized and compared on the basis of the number of glomeruli (optimal [≥20] versus suboptimal [<20]) and the pathologist's reported diagnostic confidence (high confidence versus limited confidence). Procedure details, including the operator and the use of the cortical tangential approach, were also obtained. RESULTS: For 282 patients with biopsies using 18-gauge needles, the number of passes made was significantly higher for optimal (P < .001) and high-confidence (P < .001) specimens than for suboptimal and limited-confidence specimens. The cortical tangential approach was used more frequently for optimal (P< .001) and high-confidence (P = .01) specimens than for suboptimal and limited-confidence specimens. Radiologists routinely doing ultrasound-guided procedures of all types had significantly more optimal (P= .01) and high-confidence (P= .001) specimens than radiologists with limited ultrasound experience. The distance to the kidney, cortical thickness, glomerular filtration rate, and body mass index were not significant factors. CONCLUSIONS: The ultrasound-guided procedural experience of the operator, taking more than 1 specimen, and the use of the cortical tangential approach significantly improved the pathologic material obtained during native renal biopsies.

Risk of bleeding after native renal biopsy as a function of preprocedural systolic and diastolic blood pressure.

PURPOSE: To determine the risk of bleeding complications after native renal biopsy as a function of preprocedural blood pressure (BP). MATERIALS AND METHODS: A total of 293 patients (163 men; mean age, 59.1 y) who underwent ultrasound-guided native kidney biopsy at a single institution over a 10-year period were retrospectively identified. Demographic and clinical data were collected, including systolic BP (SBP) and diastolic BP (DBP) at the time of the biopsy and presence and severity of complications. Differences in clinical and demographic data among patients with and without complications were analyzed. RESULTS: Of 293 patients, nine (3.1%) experienced major complications (required transfusion or intervention) and 10 (3.4%) experienced minor complications (pain, hematoma, or hematuria). Patients with SBP greater than 140 mm Hg or DBP greater than 90 mm Hg were 10 times more likely to experience major complications (P < .02) than patients without high BP (odds ratio [OR], 10.6; 95% confidence interval [CI], 1.3-86.0). The odds of complications were particularly increased in patients with SBP greater than 170 mm Hg (OR, 23.3; 95% CI, 2.3-234.4) and were modestly increased in patients with SBP between 141 and 170 mm Hg (OR, 7.11; 95% CI, 0.8-61.7). For DBP, the odds of complications increased with DBP greater than 90 mm Hg (OR, 7.2; 95% CI, 1.9-27.9). CONCLUSIONS: Patients undergoing native renal biopsy who have an SBP greater than 140 mm Hg or DBP greater than 90 mm Hg are at higher risk for bleeding complications. Further research is needed to determine whether medically lowering these patients' BP before kidney biopsy decreases complications.