Review
Copyright ©The Author(s) 2025. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jul 14, 2025; 31(26): 107419
Published online Jul 14, 2025. doi: 10.3748/wjg.v31.i26.107419
Evaluating luminal and post-operative Crohn’s disease activity on magnetic resonance enterography: A review of radiological disease activity scores
Richard W Lo, Gauraang Bhatnagar, Numan Kutaiba, Ashish R Srinivasan
Richard W Lo, Ashish R Srinivasan, Department of Gastroenterology and Hepatology, Austin Health, Melbourne 3084, Victoria, Australia
Richard W Lo, Ashish R Srinivasan, Department of Medicine, Austin Academic Centre, The University of Melbourne, Melbourne 3084, Victoria, Australia
Gauraang Bhatnagar, Department of Radiology, Frimley Health NHS Trust, Frimley GU16 7UJ, Surrey, United Kingdom
Gauraang Bhatnagar, Centre for Medical Imaging, University College London, London W1W 7TS, United Kingdom
Numan Kutaiba, Department of Radiology, Austin Health, Heidelberg 3084, Victoria, Australia
Ashish R Srinivasan, Department of Gastroenterology and Hepatology, Eastern Health, Melbourne 3128, Victoria, Australia
Ashish R Srinivasan, Department of Medicine, Eastern Health Clinical School, Monash University, Melbourne 3128, Victoria, Australia
Author contributions: Srinivasan AR contributed to the study concept, design and supervision; Lo RW, Srinivasan AR contributed to the drafting of the manuscript; Bhatnagar G, Kutaiba N, Srinivasan AR contributed to the critical review of the manuscript; All authors approved the submitted manuscript.
Conflict-of-interest statement: Bhatnagar G has served as a consultant for Alimentiv, is an employee of Motilent; Owns stocks and shares in Motilent; and owns patent in P295276.US.02, system to characterise topology and morphology of fistulae from medical imaging data; Srinivasan AR has served as a speaker for Sandoz and Arrowtex Pharmaceuticals, and received advisory fees from Abbvie, Amgen, Arrotex Pharmaceuticals, Pfizer, Takeda Pharmaceuticals, and Dr Falk Pharmaceuticals; The remaining authors have no disclosures.
Open Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Ashish R Srinivasan, Associate Professor, Department of Gastroenterology and Hepatology, Eastern Health, 8 Arnold St, Melbourne 3128, Victoria, Australia. ashish.srinivasan@monash.edu
Received: March 24, 2025
Revised: April 30, 2025
Accepted: June 25, 2025
Published online: July 14, 2025
Processing time: 110 Days and 18 Hours
Abstract

Magnetic resonance enterography (MRE) is a non-invasive, radiation-free imaging modality that facilitates the assessment of transmural Crohn’s disease activity. It offers advantages over ileo-colonoscopy, which is limited to mucosal-level evaluation, cannot routinely assess small bowel segments proximal to the terminal ileum, and is unable to detect extra-luminal complications. Despite these advantages, the lack of standardised criteria for defining and appraising radiologic disease activity on MRE has contributed to variability in interpretation and clinical application. In response, multiple MRE-based scoring systems have been developed to quantify radiological Crohn’s disease activity in both luminal and post-operative settings. Radiological disease activity scores specific to luminal Crohn’s disease include the magnetic resonance index of activity (MaRIA), simplified MaRIA, Nancy score, London score, Crohn’s disease magnetic resonance imaging (MRI) index, Clermont score, paediatric inflammatory Crohn’s MRE index, MRE global score, MRE index, and modified Clermont score. The MR score and the MRI in Crohn’s disease to predict postoperative recurrence index have been specifically developed to evaluate post-operative disease recurrence in Crohn’s disease. Nevertheless, heterogeneity in scoring parameters, variability in computational complexity, and a lack of consensus regarding optimal score selection, have impeded widespread clinical adoption of radiological disease activity scores. This narrative review aims to summarise the key imaging features of luminal Crohn’s disease, explore their integration into existing MRE scoring indices, and critically compare the structure, strengths, and clinical applicability of each. Furthermore, MRI scores specific to post-operative Crohn’s disease evaluation, and the assessment of cumulative bowel wall damage using the Lemann index will also be discussed.

Keywords: Crohn’s disease; Imaging; Radiological disease activity; Magnetic resonance imaging; Magnetic resonance enterography; Transumural healing

Core Tip: Magnetic resonance enterography (MRE) offers a non-invasive, radiation-free method of evaluating transmural disease activity and extra-enteric complications of Crohn’s disease. As the role of imaging grows in monitoring Crohn’s disease activity and therapy response, standardised and validated scoring systems are essential. Several MRE-based indices have been developed to quantify radiological Crohn’s disease activity reliably. These tools aim to mirror the role of endoscopic scores by providing reproducible and clinically relevant assessments of Crohn’s disease activity. Integrating these scores into clinical practice and future research promises to enhance objective disease evaluation and support more tailored, evidence-based management of Crohn’s disease.