Transrectal ultrasonography in the assessment of rectovaginal endometriosis

OBJECTIVE: To evaluate the validity of transrectal ultrasonography in the assessment of rectovaginal endometriosis. METHODS: We compared the findings of transrectal ultrasonographic examination performed before surgery with the operative and pathologic findings in 140 women who underwent laparoscopy or laparotomy for suspected endometriosis. The ultrasonographer was asked to investigate whether any deep endometriotic lesions were present in the rectovaginal septum and to define the lateral extension on the basis of involvement of the uterosacral ligaments. In addition, infiltration of the rectal and vaginal walls was evaluated. RESULTS: Thirty-four women had endometriosis infiltrating the rectovaginal septum confirmed by combined operative and pathologic findings. Ultrasonography showed a sensitivity and specificity of 97% and 96%, respectively, in the diagnosis of the presence of rectovaginal endometriosis. The sonographer identified infiltration of the rectal and vaginal walls correctly in all cases in whom it was present, but also reported rectal infiltration in three cases not confirmed by the surgeon and pathologist. The sensitivity and specificity in the diagnosis of uterosacral ligament infiltration were 80% and 97%, respectively. CONCLUSION: If our preliminary results are confirmed by a larger series, transrectal ultrasonography will be considered a valid diagnostic tool in the evaluation of rectovaginal endometriosis.