Significance of the "ovarian crescent sign" in the evaluation of adnexal masses

Introduction: This paper aimed to study the ability of the "ovarian crescent sign" to predict the nature of adnexal masses and to validate the "ovarian crescent" as an ultrasonographical marker for malignancy. Methods: A prospective study was carried out in 60 consenting women with an undiagnosed adnexal mass, attending the gynaecology service and requiring operative intervention. An ovarian crescent sign at pelvic ultrasonography was considered to be present if normal ovarian tissue was seen adjacent to the tumour area. The ultrasonographer was blinded to the reports of CA 125, and if applicable, the ascitic fluid cytology and needle aspiration biopsy. Histopathological examination report of the tumour obtained at surgery (laparotomy/laparoscopy) was considered as the gold standard. Results: 11 of 60 biopsy specimens were positive for malignancy. Normal ovarian tissue could be identified (positive crescent sign) in nearly two-thirds of cases (65 percent) scanned. Presence of normal ovarian tissue was identified in 97 percent of the benign masses. The sign was not seen in ten of the 11 cases with malignancy. Conclusion: The ovarian crescent sign as a method in prejudging the adnexal masses was found to have high sensitivity (90.9 percent) and high negative predictive value (97.4 percent).