OC11.04: Office sonovaginography: redefining the concept of a normal pelvis on transvaginal ultrasound in women with suspected endometriosis

To use sonovaginogarphy (SVG) to predict endometriosis location and severity, in women planned for laparoscopic endometriosis surgery and in turn challenge the conventional ultrasound reporting of a “normal” pelvis. Ongoing, multi-centre prospective observational study (June 2009–January 2011). All women included in this study were of reproductive age, had a history of chronic pelvic pain, and had a plan for laparoscopic endometriosis surgery. A history was obtained and an ultrasonographic evaluation with office SVG was performed on all women prior to laparoscopy. During SVG, 20 mL of ultrasound gel was inserted into the posterior fornix of the vagina, followed by the insertion of a transvaginal (TV) ultrasound probe. The gel created an acoustic window between the TV probe and the surrounding structures of the vagina, allowing for visualization of the posterior compartment. SVG was used to predict obliteration of the POD and posterior compartment deep infiltrative endometriosis (DIE) prior to laparoscopy. The correlation between SVG findings and laparoscopic findings was then analyzed to assess the ability of SVG to predict POD obliteration ± posterior compartment DIE. A total of 43 women underwent SVG followed by laparoscopy. 32/43 (74.4%) had a confirmed diagnosis of endometriosis in the past. At laparoscopy, 9/43 (20.9%) women had an obliterated POD, 16/43 (37.2%) had an endometriotic nodule(s), and 35/43 (81.4%) had superficial/peritoneal endometriosis. The sensitivity and specificity for SVG in the prediction of midline posterior compartment DIE (rectovaginal, retrocervical and rectosigmoid nodules) was 100% and 91.7%, respectively. The PPV and NPV were 70% and 100%, respectively. The sensitivity and specificity for SVG in the prediction of lateral DIE (uterosacral ligament nodules) was 33.3% and 97.3%, respectively. The PPV and NPV were 66.7% and 90%, respectively. Although the numbers are small, SVG demonstrated a high specificity/NPV, i.e. correlates highly with a “normal pelvis”. Office SVG provides additional diagnostic information to conventional pelvic sonography, which allows for the planning of specific endometriosis surgery and the need for colorectal input.