Background: Adnexal masses (AM) are a common gynecological problem. It is important to use a reliable imaging method in the differentiation of benign and malignant AMs. Purpose: To assess the accuracy and validity of the O-RADS magnetic resonance imaging (MRI) score for characterizing AM using a simplified MRI protocol. Material and Methods: The study population comprised 332 women who underwent MRI due to the detection of indeterminate AM on ultrasonography between January 2018 and June 2020. An experienced radiologist calculated the O-RADS MRI score into five categories, using an MRI protocol with a simplified dynamic study. Sensitivity, specificity, positive and negative predictive values, and area under the curve (AUC) were calculated (cutoff for malignancy, score ≥ 4). The reference standard was histopathologic diagnosis or imaging findings during >24 months of follow-up. Results: Of 237 AMs, 28 (11.9%) were malignant. The malignancy rates of AMs with scores of 1, 2, 3, 4, and 5 were 0% (0/12), 0% (0/111), 1.2% (1/77), 50% (10/20), and 100% (17/17), respectively. The O-RADS MRI score showed 96.3% sensitivity, 95.2% specificity, and 95.3% accuracy in malignancy prediction. The AUC for the differentiation of benign and malignant masses were 0.983. False positivity rate was high in cases with an O-RADS MRI score of 4 (50%). Conclusion: The O-RADS MRI score, based on a simplified MRI protocol, has high accuracy and validity in distinguishing benign from malignant sonographically indeterminate AMs. Its use in clinical practice can classify the malignancy risks of masses and prevent unnecessary surgery in benign lesions.

PURPOSE We aimed to evaluate the diagnostic performance of low-dose chest computed tomography (CT) in patients under investigation for coronavirus disease 2019 (COVID-19). METHODS This retrospective study included 330 patients suspected of having COVID-19 from March 15 to April 16, 2020. We examined 306 patients upon initial presentation using both CT and real-time reverse-transcriptase polymerase-chain-reaction (rRT-PCR). The diagnostic performance of CT was calculated using rRT-PCR as a reference. Clinical and laboratory data, CT characteristics, and lesion distribution were assessed for patients with a confirmed diagnosis via rRT-PCR. RESULTS A total of 250 patients were finally diagnosed with COVID-19. Clinical and laboratory findings included myalgia or fatigue (76%), fever (64.8%), dry cough (60.8%), elevated levels of C-reactive protein (86.4%), procalcitonin (62%), and D-dimer (58.2%), increased neutrophil-lymphocyte ratio (NLR) (54.8%), and lymphopenia (34%). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the initial CT scan were 90.4% (95% IC, 86%-93%), 64.2% (95% IC, 50%-76%), 91.8% (95% IC, 88%-94%), and 60% (95% IC, 49%-69%), respectively. The percentage of patients diagnosed on the initial rRT-PCR test was 51.6% (n=129). Most frequent CT characteristics of COVID-19 in the subgroup of rRT-PCR-positive patients were multiple lesion (97.4%, n=220), followed by bilateral involvement (88.5%, n=200), peripheral distribution (74.3%, n=168), ground- glass opacity (GGO) (69.2%, n=157), subpleural curvilinear opacity (41.6%, n=104), and mixed GGOs (27.6%, n=67). CONCLUSION rRT-PCR may produce initial false negative results. For this reason, typical CT findings for COVID-19 should be known especially by radiologists. We suggest that patients with typical CT findings but negative rRT-PCR results should be isolated, and rRT-PCR should be repeated to avoid misdiagnosis.