Magnetic resonance imaging‐quantified small bowel motility is a sensitive marker of response to medical therapy in Crohn's disease

Background: Magnetic resonance enterography (MRE) can measure small bowel motility, reduction in which reflects inflammatory burden in Crohn's Disease (CD). However, it is unknown if motility improves with successful treatment. / Aim: To determine if changes in segmental small bowel motility reflect response to anti-TNFα therapy after induction and longer term. / Methods: A total of 46 patients (median 29 years, 19 females) underwent MRE before anti-TNFα treatment; 35 identified retrospectively underwent repeat MRE after median 55 weeks of treatment and 11 recruited prospectively after median 12 weeks. Therapeutic response was defined by physician global assessment (retrospective group) or a ≥3 point drop in the Harvey–Bradshaw Index (prospective group), C-reactive protein (CRP) and the MaRIA score. Two independent radiologists measured motility using an MRE image-registration algorithm. We compared motility changes in responders and nonresponders using the Mann–Whitney test. / Results: Anti-TNFα responders had significantly greater improvements in motility (median = 73.4% increase from baseline) than nonresponders (median = 25% reduction, P 11 (median 15.2% increase, P = 0.017). / Conclusions: Improved MRI-measured small bowel motility accurately detects response to anti-TNFα therapy for Crohn's disease, even as early as 12 weeks. Motility MRI may permit early identification of nonresponse to anti-TNFα agents, allowing personalised treatment.