Diagnostic Performances of Tridimensional Rectosonography and Magnetic Resonance Imaging in Rectosigmoid Endometriosis: A Prospective Cohort Study on 101 Patients.

Tridimensional rectosonography (3-D RSG) is a transvaginal ultrasonography procedure combining intrarectal contrast with tridimensional technology. The objectives of this study were to assess the diagnostic performances of 3-D RSG in deep infiltrating rectosigmoid endometriosis using surgery and pathology as the gold standard, and to compare its results with those of magnetic resonance imaging (MRI). Patients referred for endometriosis with symptoms suggesting deep infiltrating intestinal endometriosis (DIE) were included if they agreed to undergo a 3-D RSG and MRI and if there was a surgical indication related to endometriosis. The study was a non-randomized monocentric prospective cohort study (Canadian task force classification Level II-2). From May 2012 to May 2017, 101 patients were included. Sixty patients (59.4%) had bowel involvement of the rectum (n = 21, 20.8%) or of the sigmoid (n = 39, 38.6%) confirmed in surgery and/or in pathologic testing. In the diagnosis of rectosigmoid DIE, 3-D RSG sensitivity, specificity, positive predictive value, negative predictive value, accuracy and κ index were 93%, 95%, 97%, 91%, 94% and 0.88, respectively. For MRI they were 87%, 90%, 93%, 82%, 88% and 0.76, respectively. The accuracy was not significantly different between 3-D RSG and MRI (p = 0.181). In conclusion, 3-D RSG is an effective technique to diagnose rectosigmoid endometriosis and seems to have similar diagnostic performances to MRI for this indication.

Comparison of three-dimensional rectosonography, rectal endoscopic sonography and magnetic resonance imaging performances in the diagnosis of rectosigmoid endometriosis.

STUDY OBJECTIVE: Comparison of 3D-rectosonography (3D-RSG), rectal endoscopic sonography (RES), and MRI performances in the diagnosis of rectosigmoid endometriosis using surgery as the Gold Standard. DESIGN: Monocentric retrospective longitudinal study on diagnostic procedures. DESIGN CLASIFICATION: Canadian Task Force II-2. SETTING: University Hospital of Lyon Croix-Rousse. PATIENTS: A total of 37 patients treated surgically for pelvic endometriosis. INTERVENTIONS: Expert 3D-RSG (3D Transvaginal sonography with water contrast in the rectum), MRI and RES performed by expert examiners. Sensitivity, specificity, accuracy, positive and negative predictive value, positive and negative likelihood ratios were calculated. Depth, size, and volume of intestinal lesions were also compared to the type of surgery performed (shaving versus segmental resection). MEASUREMENTS AND MAIN RESULTS: Rectosigmoid endometriosis lesion was confirmed by surgery in 31 patients on 37 (84%). Sensitivity, specificity, accuracy, positive and negative predictive value, positive and negative likelihood ratios for 3D-RSG were 94%, 100%, 95%, 100%, 75%, +∞ and 0.06 respectively; for RES 81%, 100%, 84%, 100%, 50%, +∞ and 0.19 respectively; while for MRI 90%, 100%, 92%, 100%, 67%, +∞ and 010 respectively. There was no significant difference between the 3 procedures (p > 0.05). CONCLUSION: 3D-RSG, RES and MRI seem to be 3 effective procedures in the diagnosis of rectosigmoid endometriosis. Their performances seem equivalent.