Abbreviated non-contrast magnetic resonance enterography for Crohn’s disease: a reliability study

PURPOSE: To evaluate the diagnostic reliability and time efficiency of an abbreviated non-contrast magnetic resonance enterography (MRE) protocol for assessing Crohn's disease activity. METHODS: This retrospective study included 312 patients who underwent MRE between March 2024 and November 2025. An abbreviated dataset was derived from each full examination by masking sequences not included in the abbreviated protocol, such as all contrast-enhanced acquisitions. Two radiologists independently reviewed the abbreviated and full datasets in separate sessions, fully blinded to clinical information and the alternative dataset. The interpretation of the full MRE dataset served as the reference standard. Outcomes included agreement (Cohen's kappa), sensitivity and specificity for active disease, image quality ratings (4-point scale), and estimated acquisition time. RESULTS: Agreement for overall disease activity was substantial (κ = 0.83), with sensitivity of 92.3% and specificity of 94.6% for detecting active disease. Agreement was strong for bowel wall thickening (κ = 0.85), mural edema (κ = 0.81), and the comb sign (κ = 0.79). Estimated acquisition time was 44% shorter for the abbreviated protocol (21.6 vs. 38.4 min), while diagnostic image quality was preserved (mean 3.5 ± 0.6). CONCLUSION: An abbreviated non-contrast MRE protocol provides reliable assessment of Crohn's disease activity with markedly reduced scan time and maintained image quality, supporting its use in selected follow-up scenarios.