Diffusion-weighted magnetic resonance enterocolonography in assessing Crohn's disease activity : original article

Abstract

Introduction: Diffusion-weighted magnetic resonance imaging (DWI- MRI) has the potential for identifying inflamed bowel segments for patients with Crohn's disease (CD). Objectives: We aimed to determine diffusion-weighted imaging (DWI) value to predict active CD and compare apparent diffusion coefficients (ADC) with endoscopic and conventional magnetic resonance imaging (MRI) CD activity indices. Patients and Methods: Overall, 229 patients with suspected and diagnosed CD prospectively underwent magnetic resonance enterocolonography (MR-EC) with DWI sequence and ileocolonoscopy. Magnetic resonance activity index (MaRIA), Clermont index, and CD endoscopic index of severity (CDEIS) were calculated. Results: Of the 229 investigated patients, the clinical diagnosis of CD was confirmed in 100 persons. DWI score ≥2 had 96.9% sensitivity and 82.3% specificity for diagnosing CD. A threshold ADC value of 1.30 × 10–3 mm2 /s can distinguish between normal and inflamed bowel segments with a sensitivity of 73.8% and a specificity of 98%. While using MaRIA, the threshold ADC value of 1.32 × 10–3 mm2 /s with a sensitivity of 97.9% and a specificity of 97.8% was established. There were significant differences in the DWI scores and ADC values comparing patients with inactive, mild, moderate-severe disease (P < 0.01). ADC correlated with MaRIA-G (global) (r = −0.69, P = 0.001), Clermont-G (r = −0.722, P = 0.001) and CDEIS (r = −0.69, P = 0.001). Conclusions: DWI is a valuable tool that is able to identify inflamed bowel segments as accurate as a conventional MaRIA score and to discriminate between mild and moderate and severe CD activity.