P19.04: The diagnostic value and pitfalls of transvaginal sonography (TVS) compared with pelvis CT in asymptomatic women

To evaluate the diagnostic value of TVS compared with pelvis CT in routine gynecologic examination of asymptomatic women. Total number of women who underwent gynecologic examination added up 12,093 between June 2004 and July 2005. Among them, we performed retrospective analysis of 766 asymptomatic women who simultaneously underwent TVS and pelvis CT. Two gynecologists, having respectively 8 and 7 years' experience in pelvic ultrasonography, conducted two dimensional TVS (LOGIQ 9, GE, USA) and three radiologists reviewed CT images. 453 of the 766 women had no abnormal findings in both examinations. In 154 women, both yielded the same diagnosis and the most common finding was uterine leiomyoma (123/154). In 115 cases, only TVS yielded abnormal findings consisted of 66 leiomyoma, 6 adenomyosis, 29 endometrial pathology, and 14 ovarian cysts. The mean size of leiomyoma in TVS was 1.51cm (0.6–3.4cm). In contrast, 44 women corresponded to normal state in TVS, but not in CT. Of the 38 women with ovarian cysts in CT, 36 were categorized as having physiologic cysts by gynecologists. However, two false negative cases had histopathologic diagnosis of mature cystic teratoma. One had an inadequate TVS assessment due to severe bowel movement. In the other, practitioner couldn't identify one of two ovaries owing to huge leiomyoma. Also in two premenopausal women, CT yielded a diagnosis of endometrial cavity dilatation, but normal thickness and feature in TVS. Especially both women had endometrial cells in pap smear, who were respectively 44 and 49 years old. Other exclusive CT finding was four pelvic congestion syndromes. Method of image sectioning and diversity of contrast resolution at different time points in CT might have led to an underestimation of the frequency of small leiomyoma or endometrial pathology. In asymptomatic women with severe bowel movement or enlarged uterus, careful evaluation of adnexa with TVS should be performed.