Comprehensive Review of Magnetic Resonance Enterography-Based Activity Scoring Systems for Crohn’s Disease

Magnetic resonance (MR) enterography (MRE) plays a pivotal role in the management of patients with Crohn's disease (CD) throughout the chronic disease process.With advantages such as its non-invasiveness and the ability to use several MR sequences to reflect findings of active inflammation, several MRE-based indices have been introduced to assess CD inflammatory activity.Although there is no universally accepted gold-standard score for clinical practice, the most studied scores include the Magnetic Resonance Index of Activity, simplified Magnetic Resonance Index of Activity, Nancy score, Clermont score, London score, and CD MRI Index.These MRE-based scoring systems share certain characteristics but also differ in terms of the imaging parameters included, the bowel segments evaluated, and the MR sequences required for assessment.This review article covers the key MR findings of active inflammation incorporated into these scoring systems, along with the detailed characteristics and clinical applications of MRE-based scoring systems in adult patients with CD.