Identifying secondary bowel stenosis:MRI diffusion-weighted imaging in Crohn′s disease / 医学研究生学报

ABSTRACT

[Abstract ] Objective Stenosis is a common complication of Crohn′s disease (CD), different treatments for different cau-ses.The article aimed to investigate bowel stenosis by the application of MRI diffusion-weighted imaging(DWI) and explore its value of identifying CD. Methods From Jan 2014 to Jun 2014, 31 patients with histologically proven CD (18 males and 13 females;mean age38.90 ±13.65 years) were recruited in this approved retrospective study .All patients underwent conventional 3.0T MRI and DWI sequences .According to the most serious stenosis part identified by MRI , DWI sequence examination was added and the apparent diffusion coefficient (ADC) of the lesion was measured.All patients would undergo colonoscopy in 24 hours.According to the endo-scopic manifestations and pathological results , the patients were divided into inflammatory group (n=21) and fibrotic group (n=10). We observed the difference of ADC between two groups and worked out the cutoff points . Results In the inflammatory group , the ADC value andthe mean ADC value of stenosis bowel wall were (1.01 ±1.83) ×103 mm2/s and (1.40 ±0.23) ×103 mm2/s, whereas (0.53 ±1.03) ×103 mm2/s and (0.80 ±0.16) ×103 mm2/s in the fibrotic group(P<0.05).The area under receiver operating characteristic curve was 0.981 (95%confidence interval 0.943-1.000), taking 1.11 ×103mm2/s as the cutoff point.The sensitivity of low ADC values in detecting inflammatory bowels was 90.5%, and the specificity of high ADC values in excluding inflammatory bowels was 100%. Conclusion Different pathological components limit the movement of water molecular at different degrees , therefore quantitative parameters can be acquired by measuring ADCs , which contributes to the identification and diagnosis of CD secondary bowel stenosis.