Crohn Disease Strictures: Multimodality Imaging to Identify Imaging Biomarkers.

The morphologic imaging features of Crohn disease (CD) small bowel strictures have been defined by intersociety recommendations and expert panels. CD small bowel strictures result in penetrating and obstructing complications that often lead to surgery. Imaging biomarkers in fibrostenosing CD can be used to reproducibly diagnose and measure strictures and identify those at high risk for subsequent surgery. Emerging biomarkers seek to accurately and reproducibly identify and measure histopathologic correlates of fibrosis, inflammation, and smooth muscle hyperplasia or hypertrophy, as well as to reflect biomechanical properties such as stiffness. The authors review and define imaging features of small bowel strictures using routine MR and CT enterography, which should be incorporated into clinical reports to guide management decisions or to use in clinical trials. The most promising quantitative imaging biomarkers reflecting histopathologic composition of small bowel strictures are reviewed with a focus on MRI and US methods. Imaging is a critical tool for the management of patients with stricturing CD. ©RSNA, 2025 See also the related articles by Rieder and Ma et al and Rieder et al in Radiology.