Defining probabilities of bowel resection in deep endometriosis of the rectum: Prediction with preoperative magnetic resonance imaging

AimDeep endometriosis of the rectum is a highly challenging disease, and a surgical approach is often needed to restore anatomy and function. Two kinds of surgeries may be performed: radical with segmental bowel resection or conservative without resection. Most patients undergo magnetic resonance imaging (MRI) before surgery, but there is currently no method to predict if conservative surgery is feasible or whether bowel resection is required. The aim of this study was to create an algorithm that could predict bowel resection using MRI images, that was easy to apply and could be useful in a clinical setting, in order to adequately discuss informed consent with the patient and plan the an appropriate and efficient surgical session.MethodsWe collected medical records from 2010 to 2016 and reviewed the MRI results of 52 patients to detect any parameters that could predict bowel resection. Parameters that were reproducible and with a significant correlation to radical surgery were investigated by statistical regression and combined in an algorithm to give the best prediction of resection.ResultsThe calculation of two parameters in MRI, impact angle and lesion size, and their use in a mathematical algorithm permit us to predict bowel resection with a positive predictive value of 87% and a negative predictive value of 83%.Conclusions MRI could be of value in predicting the need for bowel resection in deep endometriosis of the rectum. Further research is required to assess the possibility of a wider application of this algorithm outside our single-center study.