Diffusion-weighted magnetic resonance enterocolonography and CDEIS in assessing Crohn’s disease activity

Abstract

Introduction: Crohn’s disease (CD) usually affects young adults and can have a progressive and disabling course. Therefore early diagnosis and monitoring of activity are essential. The development of magnetic resonance imaging (MRI) sequences in the last decade has made MRI of the bowel a very attractive diagnostic tool of CD. Magnetic resonance enterocolonography (MR-EC) is a non-invasive imaging modality that complements ileocolonoscopy. The diffusion-weighted imaging (DWI) creates contrast through the motion of water and other small molecules with tissue, which allows qualitative and quantitative functional analysis. The sequence is non-time consuming, and the most significant advantage is that no intravenous contrast is needed. Different pathological features, such as cell density, extracellular matrix, nucleic areas, and membrane permeability, can be assessed by DWI quantified with an apparent diffusion coefficient (ADC). Aims & Methods: This study aimed to determine the potential of DWI in the evaluation of patients with CD as a new opportunity to extend MR-EC capacity by comparing DWI with endoscopic activity index. Overall, 229 patients with suspected CD prospectively underwent magnetic resonance enterocolonography (MR-EC) with DWI sequence and ileocolonoscopy. CD endoscopic index of severity (CDEIS) was calculated. Results: Of the 229 investigated patients, the clinical diagnosis of CD was confirmed in 100 persons. Using a receiver operating characteristic curve, we showed that 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 healthy and inflamed bowel segments with a sensitivity of 73.8% and a specificity of 98% using the Copenhagen diagnostic criteria as a reference standard.[...].