Magnetic resonance imaging (MRI) allows accurate assessment of Crohn's disease (CD), but requires gadolinium injection.
Diffusion-weighted (DW)-MRI yields comparable performances in small bowel Crohn's disease.
Dr Buisson and colleagues from France compared the accuracy of DW-MR enterocolonography (MREC) and the magnetic resonance index of activity (MaRIA), and performed an external validation of the Clermont score in assessing inflammation in Crohn's disease.
The research team performed an observational prospective study of a single-center cohort.
|The Clermont score was highly correlated with the MaRIA in ileal Crohn's disease |
|American Journal of Gastroenterology|
A total of 130 Crohn's disease patients underwent consecutively MREC with gadolinium injection and DWI sequences between 2011 and 2012.
Of the 848 evaluated segments, 21% were active defined as MaRIA ≥7.
Using a receiver operating characteristic (ROC) curve, the researchers determined an apparent coefficient of diffusion (ADC) threshold of 1.9 × 10−3 mm2/s that yielded a sensitivity and a specificity in discriminating active from nonactive CD of 97% and 98%, respectively, for the colon/rectum, and 86% and 82%, respectively, for the ileum.
The researchers observed that apparent coefficient of diffusion was better correlated to MaRIA ≥7 than related contrast enhancement obtained with injected sequences.
The Clermont score was highly correlated with the MaRIA in ileal Crohn's disease but not in colonic Crohn's disease.
The team reported that interobserver agreement was high with regard to apparent coefficient of diffusion measurement.
Dr Buisson's team concludes, "DW-MREC is a reliable tool to assess inflammation in colonic, and ileal Crohn's disease, and its use in daily practice would avoid gadolinium injection."