Evaluating the inflammatory activity in Crohn's disease using magnetic resonance diffusion kurtosis imaging

ObjectivesTo explore the feasibility of diffusion kurtosis imaging (DKI) for evaluating inflammatory activity in Crohn's disease (CD).Materials and methodsIn all, 51 CD patients were included, who were performed with consecutive enteroscopy, MR and DKI (b values=0-2000mm(2)/s). The lesions of bowel segments were graded as inactive (0-2), mild (3-6), and moderate-severe group (>6) based on simplified endoscopic activity score for Crohn's disease (SES-CD), The abilities of the parameters of DKI and DWI in grading different activity lesions were compared.ResultsOne hundred and twenty-seven bowel segments including inactive (15), mild (45) and moderate-severe (67) were analyzed. ADC (r=-0.627, p<0.001), D-app (r=-0.381, p<0.001) and K-app (r=0.641, p<0.001) were correlated with SES-CD. These parameters were significantly different among the three groups (all p<0.001). ROC analysis found ADC had the highest accuracy (AUC=0.884, p<0.001) to differentiate inactive from active group with the threshold at 0.865x10(-3)mm(2)/s, which was slightly higher than K-app (AUC=0.867, p<0.001) with the threshold at 0.645, and was obviously higher than D-app (AUC=0.726, p=0.005). Similarly, ADC also had the highest accuracy (AUC=0.846, p<0.001) to differentiate inactive-mild from moderate-severe group with the threshold at 0.825x10(-3)mm(2)/s, and minimally higher than K-app (AUC=0.843, p<0.001) with the threshold at 0.695, and obviously higher than D-app (AUC=0.690, p<0.001).ConclusionDKI is feasible and comparable to conventional DWI for the evaluation of inflammatory activity in CD.