Plain magnetic resonance imaging as an alternative in evaluating inflammation and bowel damage in inflammatory bowel disease – a prospective comparison with conventional magnetic resonance follow-through

Abstract

Objective. To compare prospectively the diagnostic accuracy of magnetic resonance imaging (MRI) without use of contrast medium orally or intravenously (plain MRI) with magnetic resonance follow-through (MRFT) in patients with inflammatory bowel disease (IBD). Material and methods. Plain MRI was carried out in addition to MRFT, to which the patients were referred. All patients underwent both examinations on the same day. For the evaluation, the bowel was divided into nine segments. Two radiologists, blinded to clinical findings, evaluated bowel wall thickness, diffusion weighted imaging (DWI), and other inflammatory changes in each bowel segments. Further, hyperenhancement of the bowel was also evaluated in MRFT. Results. A total of 100 patients (40 males and 60 females; median age: 38.5; range: 19–90) were enrolled; 44 with Crohn’s disease (CD), 25 with ulcerative colitis (UC), 24 with IBD unclassified (IBD-U), and 7 had other diagnosis. Sensitivity, specificity, and accuracy in CD ranged 50–86%, 93–94%, and 91–92% for wall thickening and 49–82%, 85–93%, and 84–89% for DWI, respectively. Sensitivity, specificity, and accuracy in UC range 0–40%, 87–100%, and 80–100% for wall thickening and 0–52%, 83–94% and 76–92% for DWI, respectively. The κ values for bowel wall thickening, DWI, and mural hyperenhancement were detected with fair agreement (κ = 0.26–0.39) at both MRI examinations, whereas only bowel wall thickening in MRFT were detected with moderate agreement (κ = 0.47) Conclusion. Plain MRI cannot currently replace MRFT in the workup of patients with IBD. Further research on plain MRI is needed to improve the protocol.

Key Words:

• Apparent diffusion coefficient
• computed tomography
• Crohn’s disease
• diffusion weighted imaging
• inflammatory bowel disease
• inflammatory bowel disease unclassified
• magnetic resonance follow-through
• magnetic resonance imaging
• magnetic resonance imaging enteroclysis
• ulcerative colitis

Acknowledgments

The authors want to express their gratitude to Jakob Moller, M.Sc., for assistance with MRI protocol, Rasmus Hvass Hansen, PhD, for statistics advices, and Krister Reinholdt Nielsen, Cand.scient, for language support. This project was supported in part by CCF grant.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.