[Diagnosis of ovarian tumors by ultrasonography and X-ray CT].

A drawback in ultrasonography, an indispensable technique in imaging ovarian malignancies, is that it sometimes shows false positive for benign tumors including dermoid cyst and ovarian endometriosis. To overcome this, the concurrent use of X-Ray CT seems warrantable and this led us to carry out the study summarized below. CT was carried out on 268 of 322 ovarian cases which had undergone ultrasonography. The results obtained were as follows. Sensitivity of ultrasonography and CT in ovarian malignancies were 82% and 88% respectively. Of the cases subjected to both techniques, those who were deemed false positive were 39 in ultrasonography and 12 in CT. Ultrasonographic imagings of dermoid cyst and ovarian endometriosis were classified on the basis of their patterns. The results obtained revealed that those in which it was difficult to discriminate the image from ovarian malignancy were types V and VI in dermoid cyst and type III-C in ovarian endometriosis. In both dermoid cyst and ovarian endometriosis, nearly a 100% accuracy rate was obtainable with CT for diagnosis of benign tumors. This strongly suggested that concurrent use of CT was required, in diagnosing ovarian diseases with the V or VI and III-C patterns referred to above.