The ultrasonographic evaluation of large cystic pelvic masses.

Thirty-six large cystic masses of pelvic origin were evaluated by means of gray-scale ultrasonography. The goal was to determine which sonographic criteria would help establish whether a lesion was malignant or benign, to further characterize it into ovarian neoplasms (cystadenoma, teratoma), inflammatory lesions (tuboovarian abscess), and blood-containing lesions (hematocolpos, hematoma). Eighty-three percent of the masses were benign, and 72% were of ovarian origin. Fifty-six percent of the masses were found in women 11 to 30 years old. Although no pathognomonic patterns were discovered, the application of certain sonographic criteria may narrow the differential diagnoses considerably.