Application Of MRE In The Diagnosis And Evaluation Of Disease Activity In Crohn's Disease

Objective: To assess the value of magnetic resonance enterography(MRE)in the diagnosis of Crohn's disease(CD)and in the evaluation of the CD disease activity.Methods: One hundred and eighty nine patients met the study criteria were included in this study.Accroding to the disease diagnosis,the patients were divided into group CD(n=127),suspected CD(gruop s CD,n=28)and non-CD(group n CD,n=62).And then the CD patients were subdivided into remission(group r CD),mild activity(group m CD)and moderate-severe activity(group s CD)group according to their Best CDAI.The MRE data and clinical data were collected and their relationships were evaluated.Result:1.A total of 1507 bowel segments 189 patients were observed,the lesions located on the terminal ileum accounted the highest(29.30%)in CD patients.In group CD,incidence rate of intestinal wall thickening,intestinal stricture,“comb sign”,mesenteric fat interval fuzzy,fistula and abscess were significantly higher than erther in group s CD or in group n CD(P<0.05).However,the thickness,enhancement degree,enhancement way,SI of b=50s/mm(50SI)in lesion intestinal segments showed no significant differences among the three groups(p>0.05).In group CD,the intestinal wall thickness,50 SI and 800 SI in lesion intestinal segments were significantly higher than that in non-lesion intestine segments,and the value of ADC was significantly lower than in non-lesion intestine segments(p<0.05).The 800 SI in lesion intestinal segments in group CD was higher than in group n CD.The ADC value in group CD was lower than either in group s CD or in group n CD(P<0.05).2.There was no significant difference in the detection rate of intestinal stricture,“comb sign”,mesenteric fat interval fuzzy,fistula or abscess among CD patients with different disease activities(P>0.05).The mean thickness of lesion intestinal segments in group s CD(6.16±2.58mm)was significantly higher than either in group r CD(5.16±1.86mm)or in group m CD(5.85±2.04mm)(P=0.004),and Intestinal wall thickness was positively correlated with Best CDAI(r=0.141,P=0.120)in group CD.Although there was no significant difference of the enhancement degree among the three groups(p=0.069),but the enhancement way was different(?2=13.310,P=0.038),which showed mainly homogenous enhancement(47.50%)the group r CD,stratified enhancement(44.20%)and heterogeneous strengthening(44.20%)in group m CD,and stratification enhancement(54.60%)in group s CD.The 50 SI and 800 SI were positively correlated with Best CDAI(P<0.05),and ADC value was negative correlated with Best CDAI(r=-0.357,P=0.000).3.The level of Ig G on food intolerance had positively correlated with Best CDAI(r=0.377,P<0.05),50SI(r=0.170,P=0.004),800SI(r=0.311,P=0.000)respectively,however showed a negative correlated with ADC value(r=-0.141,P=0.016).4.At the ROC curves,When ADC value was 1.95×103mm2/s,the sensitivity of the ADC to predict intestinal lesions was 79.4% and the specificity was 85.8%.Taking ADC value as 1.84×103mm2/s,the sensitivity was 83.90%,and specificity was90.00%.Conclusion: MRE can simultaneously observe the intestinal wall and parenteral complications of CD patients.Among CD patients with different disease activities,the enhancement degree of intestinal wall was similar,but the enhancement patter,thickness of intestinal,SI(b=50s/mm2 and b=800s/mm2)and ADC value were significantly different.So MRE can help to diagnose CD,and contribute to evaluate the disease activity,with a simple,repeatable,non-radiation advantages.