Paraovarian and paratubal cysts: preoperative diagnosis using transabdominal and transvaginal sonography.

OBJECTIVE: Paraovarian and paratubal cysts constitute about 10% of adnexal masses. Our purpose was to determine whether pathologically proven examples of these lesions were correctly identified during preoperative transabdominal and transvaginal sonographic evaluations.

METHODS: Between 1990 and 1994, 15 women with 10 paraovarian cysts and 5 paratubal cysts undewent preoperative sonography. The sonograms were performed using transabdominal and transvaginal probes. Mean interval before surgery was 22 days (range: 1-96 days). The sonographic interpretation at the time of the examination was correlated with the pathological findings.

RESULTS: In only 1 of 15 patients was a paraovarian or paratubal cyst suggested before surgery. Paraovarian cysts were misdiagnosed as ovarian cysts. Because of the microscopic size of paratubal cysts in our series, none was diagnosed before surgery and these were usually an incidental finding in patients with ovarian masses.

CONCLUSIONS: In our experience, paraovarian and paratubal cysts are difficult to diagnose before surgery with the use of transabdominal and transvaginal sonography. We speculate that when there is close proximity of a paraovarian cyst to the ovary, an ovarian cystic mass cannot reliably be differentiated from a paraovarian cyst.