Extraovarian cystadenomas: ultrasound and MR findings in 7 cases.

Objective: To describe the ultrasound and MR appearance of paraovarian cystadenomas.

Methods: We reviewed retrospectively the radiologic findings in 7 patients with surgically proven paraovarian cystic neoplasms, including 6 serous cystadenomas and 1 borderline seromucinous cystadenoma. All had ultrasound and 4 had MR preoperatively.

Results: On ultrasound, the ipsilateral ovary was visualized in six cases, in contact with the cyst in five and separate from it in one. On MR, the ovary and the cyst were visible in four cases, in contact in three and separate in one. Internal papillary excrescences, present at pathology in all cysts, were seen in five on ultrasound and in four on MR.

Conclusion: Although the extraovarian location of these neoplasms is difficult to determine preoperatively by ultrasound and MR, these imaging modalities are more reliable in predicting the histology of these rare lesions and differentiating them from simple paraovarian cysts.