ORIGINAL ARTICLE Gynaecology The value of MRI in assessing parametrial involvement in endometriosis

study question: What is the accuracy of magnetic resonance imaging (MRI) in the diagnosis of parametrial endometriosis in com-parison with surgicopathological findings? summary answer: MRI displayed an accuracy of 96.4 % in the preoperative diagnosis of parametrial involvement by deep infiltrating endometriosis (DIE). what is known and what this paper adds: MRI is the best technique for preoperative mapping of DIE. This preliminary paper shows that T2-weighted MRI is a valuable tool for the preoperative evaluation of parametrial involvement by endometriosis. design: A retrospective study of an MRI database was used to identify examinations performed in women, who had a clinical suspicion of pelvic endometriosis (n 666), between 2005 and 2009 in a university medical centre in France. participants and setting: Exclusion criteria were previous surgery for DIE, incomplete surgical evaluation, repeat MRI examinations and incomplete MR protocol. Only symptomatic patients who underwent surgery with a pathological correlation were included (n 83). An experienced radiologist, blind to the surgical and histological findings, evaluated sagittal, axial and thin-section oblique axial MR images obtained from the 83 patients. data analysis method: Descriptive statistics and Fisher exact test were used. main findings: The prevalence of DIE and parametrial endometriosis was 76/83 (91.6%) and 12/83 (14.5%), respectively. The sen-sitivity, specificity, positive and negative predictive values, accuracy and positive and negative likelihood ratios for the diagnosis of parametrial