Anatomical localization of deep infiltrating endometriosis: 3D MRI reconstructions

Purpose: The goal of this study was to determine the accuracy of three-dimensional (3D) MRI reconstructions obtained with segmentation technique in the preoperative assessment of deep infiltrating endometriosis (DIE) and in particular to evaluate rectosigmoid and bladder wall involvement. Materials and methods: Institutional review board approval for this study was obtained, and each patient gave written informed consent. Fifty-seven consecutive patients with diagnosis of DIE who had undergone pelvic MRI at 1.5 T before surgery between 2007 and 2011, were retrospectively evaluated and 3D post-processed in order to obtain a detailed mapping of DIE. A blinded reader interpreted images. MRI results were compared with surgical findings and were scored by using a fourpoint scale (0_3 score). Results: 36/57 patients with symptomatic DIE underwent surgery: 18/36 had endometriotic nodules infiltrating the rectouterine pouch, 12/36 the vesicouterine pouch, and 6/36 the rectovaginal pouch. The sensitivity of MRI and 3D MRI vs. surgery was, respectively, 64% vs. 83%; diagnostic accuracy of 3D MRI respect to MRI alone was 86% vs. 67% for localization; 86% vs. 67% for dimension; 79% vs. 58% for rectosigmoid infiltration; 92% vs. 75% for bladder infiltration. Conclusions: In this preliminary study, 3D MRI reconstructions obtained with semi-automatic method of segmentation provided encouraging results for staging