Comparison of Magnetic Resonance and Balloon Enteroscopic Examination of the Small Intestine in Patients With Crohn's Disease

BACKGROUND & AIMS: Magnetic resonance (MR) enterography is a recommended imaging technique for detecting intestinal involvement in Crohn's disease (CD). However, the diagnostic accuracy of MR enterography has not been compared directly what that of enteroscopy of the jejunum and proximal ileum. We evaluated the usefulness of MR enterocolonography (MREC) by comparing its findings with those from balloon-assisted enteroscopy. METHODS: In a prospective study, MREC and enteroscopy were performed within 3 days of each other on 100 patients. Ulcerative lesions and all mucosal lesions were evaluated. Physicians and radiologists were blinded to results from other studies. Findings from MREC were compared directly with those from enteroscopy; the sensitivity and specificity with which MREC detected CD lesions were assessed. RESULTS: MREC detected ulcerative lesions and all mucosal lesions in the small intestine with 82.4% sensitivity (95% confidence interval [CI], 75.4%-87.7%) and 67.5% sensitivity (95% CI, 63.1%-70.0%); specificity values were 87.6% (95% CI, 83.7%-90.6%) and 94.8% (95% CI, 90.1%-97.5%). MREC detected major stenosis with 58.8% sensitivity (95% CI, 37.6%-77.2%) and 90.0% specificity (95% CI, 88.4%-91.5%) and all stenoses with 40.8% sensitivity (95% CI, 30.8%-49.4%) and 93.7% specificity (95% CI, 91.1%-95.9%). CONCLUSIONS: MREC is useful for detecting active lesions in the small intestine. However, MR imaging is less sensitive for detecting intestinal damage, such as stenoses. Enteroscopy is preferred for identifying intestinal damage. Suitable imaging approaches should be selected to assess CD lesions in deep small intestine.