ESUR consensus MRI for endometriosis: protocol, lexicon, and compartment-based analysis.

objectiveTo propose an update of ESUR endometriosis guidelines to reflect advances in MRI protocol and lexicon.

methodsA literature search was followed by a DELPHI process among 20 experts.

resultsPre-imaging preparation, including fasting, antiperistaltic agents, moderate bladder filling, and bowel preparation, is recommended. A comprehensive magnetic resonance imaging (MRI) protocol should include multiplanar T2W, T1W, and sequences covering the kidneys. Superficial endometriosis should be described on T1WFS as high signal intensity foci on the peritoneal surface. Endometriomas should be described in terms of multiplicity, signal intensity, central or peripheral location, and bilaterality. MRI evaluation of deep pelvic endometriosis (DE) should be performed by dividing the pelvis into compartments using two horizontal and vertical lines. A bladder nodule should be described according to location, size, and the distance to the ureteric orifice provided. A uterosacral ligament must be considered abnormal if a nodule or spiculation is visible in at least two planes or if a bright T1W spot is detected. A posterior vaginal wall nodule should be measured. External adenomyosis should be described according to location and size. The description of a rectosigmoid nodule includes location, number of nodules, longitudinal extent, distance to the anal verge, and wall thickening. The lateral compartment includes the anterior distal round ligament, the mediolateral and posterolateral parametrium. Abdominal wall nodules, ileocaecal junction, appendiceal nodules, and sigmoid nodules, must be systematically described.

conclusionA standardized MRI protocol and lexicon based on compartmental analysis are crucial for improving communication and management of patients referred with endometriosis. KEY POINTS: Question ESUR's endometriosis guidelines were last published in 2017; an update is provided to reflect advances in MRI techniques and the need for a standardized lexicon. Findings MRI protocol must include multiplanar T2W sequences, a T1W sequence, and a kidney visualization sequence. A standardized report based on a compartmental analysis is recommended. Clinical relevance Using a standard MRI protocol with compartmental analysis of endometriotic nodule locations and adopting a standardized vocabulary is crucial for comprehensive mapping and effective communication with both the patient and the surgeon.