2.1. Patients

This Health Insurance Portability and Accountability Act for a compliant, single-institution, and retrospective pilot study has been approved by the institutional review board (ethics committee of the “Iuliu Hațieganu” University of Medicine and Pharmacy Cluj-Napoca; registration number, 50; date, 11.03.2019), and a waiver consent was obtained owing to its retrospective nature. In our radiology database, reports of pelvic MRI scans were searched from January 2017 to February 2020 using the keywords: “endometriosis”, “endometrioma/s”, “hemorrhagic cyst/s”, and “ovarian cyst/s”. The original search yielded 162 reports. Each report was then analyzed and those studies in which the keyword in the report did not refer to the presence of an ovarian hemorrhagic cyst were excluded (n = 47). The medical records of the remaining 115 patients were retrieved from the archive of our healthcare unit and investigated for disease-related data. The other exclusion criteria were: other benign or malignant ovarian lesions complicated by bleeding (n = 8), lesions with a diameter of less than 15 mm (n = 19), the presence of artifacts within the T2WI (n = 6), patients without a final clinical or pathological diagnosis of the lesion (n = 21), or patients who did not undergo gynecological follow-up (n = 18).