Inflammatory Bowel Disease Evaluated by Low-Field Magnetic Resonance Imaging Comparison with Endoscopy, 99m Tc-HMPAO Leucocyte Scintigraphy, Conventional Radiography and Surgery

Abstract

Background: To evaluate the use of low-field magnetic resonance imaging (MRI) in active inflammatory bowel disease (IBD). Methods: MRI was executed in a consecutive cohort of 28 patients with Crohn disease (CD) and in 17 with ulcerative colitis (UC) prior to glucocorticoid treatment (1 mg prednisolone orally/kg body weight/day). MRI was repeated after 2-3 weeks (22 CD, 12 UC), and again after treatment completion or prior to surgery (18 CD, 6 UC). Five bowel segments were evaluated separately. MRIs were blindly evaluated by two observers, and findings compared with 39 leucocyte scintigraphies, 38 endoscopies, 15 double-contrast barium enemas, 66 small-bowel radiographic examinations and surgery in 23 patients. Results: In CD, blinded evaluation revealed a kappa ( &#115 ) of 0.84 (95% confidence interval (CI) 0.78-0.91). In UC, &#115 was 0.66 (95% CI 0.55-0.78). Agreements regarding disease extension between MRI and other modalities in CD were found in 345 bowel segments out of 391 (88.2%) at risk, and in UC in 209/235 (88.9%). Colonic disease activity gradings by radiography and endoscopy correlated significantly with T2-signal intensity (SI T2 ) and increments in T1-signal intensity (%SI T1 ) in both diseases. Significant correlations between MRI indices of disease activity and CDAI in CD (MRI-SI T2 : P < 0.0001; MRI% SI T1 : P = 0.0008) and the Powell-Tuck index in UC (MRI% SI T1 : P = 0.008) were found. Conclusions: With low interobserver variation and high concordance of findings with other examinations, low-field MRI seems a valuable modality in active IBD. In addition, MRI expressions of disease activity correlate to clinical, radiographic and endoscopic disease activity.

• Crohn Disease
• Inflammatory Bowel Disease
• Magnetic Resonance Imaging
• Ulcerative Colitis