Ultrasound and the pelvic mass.

We compared the findings from pelvic examination, preoperative ultrasound and surgery on 50 patients who underwent exploratory laparotomy for a pelvic mass at Tulane University Medical Center. Of the 50 cases, 34 (68%) were correctly diagnosed as a pelvic mass by both pelvic examination and ultrasonography. Ultrasound had nine false negatives (21%) and only one false positive (2%). Pelvic examination had 7 false positives (16%). There was no statistical difference by chi-square analysis in the accuracy between ultrasonography and pelvic examination in the detection or diagnosis of the masses. Ultrasound indicated pathology not associated with the suspected mass in ten patients; surgery confirmed pathology in five of them. More errors occurred on both pelvic examination and ultrasonography in obese patients than in nonobese ones: seven of the ten ultrasound errors occurred in obese patients, and five of the seven pelvic exam errors also occurred in obese patients. In the nine cases of false-negative ultrasound findings surgery was postponed, but all of them eventually underwent surgery because of a deteriorating clinical course. In our study pelvic ultrasonography was not beneficial in the management of patients with a known or suspected pelvic mass, but it was very accurate for confirmation of a mass.