Computed tomography of benign ovarian masses.

Although ultrasound is the primary imaging modality for evaluating benign gynecologic pelvic masses, CT may provide diagnostic information regarding ovarian masses that are discovered fortuitously. The relatively infrequent use of CT in evaluating the adnexa has resulted in a paucity of literature regarding the CT characteristics of benign ovarian masses. The CT appearances of 24 benign ovarian masses are presented. Pathologic diagnoses were ovarian cyst (nine), endometrioma (five), teratoma (three), serous cystadenoma (two), mucinous cystadenoma (two), thecoma (one), cystadenofibroma (one), and Brenner tumor (one). Benign ovarian cysts have characteristic homogeneous water density and smooth walls on CT. Single internal septations and slight wall irregularity are also common features, but soft-tissue mural or septal nodules are uncommon. Computed tomography can be diagnostic in evaluating cystic teratomas. Other benign ovarian masses exhibit a spectrum of CT appearances that is often nonspecific, and surgical or biopsy proof may be necessary to exclude malignancy.