摘要
目的:以结肠镜检查为参考标准,探索磁共振结肠成像(MRC)结合DWI,在评估活动期溃疡性结肠炎的价值。方法:搜集经临床、肠镜及病理证实的活动期溃疡性结肠炎患者25例,根据改良Truelove-Witt's标准将患者分为轻度、中度、重度三组,比较不同组间MRC表现差异。MRC主要评价指标:粘膜动脉期强化、肠壁增厚、周围增大淋巴结、靶征、梳齿征、深溃疡、病变肠段DWI高信号、病变肠段与正常肠段的ADC值,并绘制ROC曲线确定最佳诊断阈值。结果:总共125段肠管(73段结肠镜发现炎症存在,52段未发现炎性改变),MRC有很高的诊断准确性(阳性预测值96.1%,敏感性97.3%;阴性预测值96.3%,特异性94.5%),与结肠镜检查结果一致性非常好(K=0.921,P=0.000)。25例活动性溃疡性结肠炎患者中,轻度组4例,中度组10例,重度组11例。肠管周围淋巴结增大在轻度组与中度、重度组间有显著性差异(P=0.015,P=0.001);靶征在轻度组与重度组间有显著性差异(P=0.004);梳齿征在轻、重度组间有显著性差异(P=0.004);而粘膜动脉期强化、肠壁增厚及DWI高信号在三组间无显著性差异(P>0.05);深溃疡仅出现在重度组;病变肠段与非病变肠段ADC值间有显著性差异(P<0.05),当ADC值小于2.135×10-3 mm2/s判断为活动性UC,其敏感性和特异性分别为95.7%和78.3%,ROC曲线下面积值为0.980。结论:磁共振结肠成像(MRC)结合DWI在评估溃疡性结肠炎的活动性、病变范围及严重程度有较准确的诊断价值。
Objective：The aim of this study was to explore the diagnostic value of magnetic resonance colonography（MRC）combined with diffusion-weighted imaging（DWI）in patients with active ulcerative colitis（UC）using endoscopy as the reference standards.Methods：Twenty-five patients with active UC confirmed by clinical manifestation,colonoscopy and pathology underwent MRC examinations in the study.According to the modified Truelove-Witt＇s criteria,the patients were divided into three groups as mild,moderate and severe,and the MRC manifestations were compared among the three groups.MRC parameters evaluated in each patient were：mucosal hyperenhancement in the arterial phase,bowel wall thickness,enlarged mesenteric lymph nodes,target sign,comb sign,deep ulcers,DWI hyperintensity,and apparent diffusion coefficient（ADC）values of the involved bowel segments and the normal colon.The receiver operating characteristic（ROC）curve analysis was used to determine the ADC cutoff value for differentiation.Results：A total of 125 bowel segments（73with endoscopic active colonic inflammation;52normal）were included.MRC detected endoscopic inflammation with high diagnostic accuracy（positive predictive value 96.1%,sensitivity 97.3%;negative predictive value 96.3%,specificity94.5%）,the kappa coefficient between MRC and endoscopy was very high（K=0.921,P=0.000）.Among the 25 patients with active ulcerative colitis,4were mild,10 were moderate,and 11 were severe.Enlarged mesenteric lymph nodes were significantly different between the mild group and the moderate to severe group（P=0.015,P=0.001）;the target sign was significantly different between the mild group and severe group（P=0.004）;the comb sign was significantly different between the mild group and severe group（P=0.004）.However,arterial mucosal hyperenhancement,bowel wall thickening,and DWI hyperintensity showed no significant difference between the three groups（P0.05）.The deep ulceration was only found in the severe group.The ADC values were significantly different between the involved segments and the normal segments（P0.05）.Cutoff ADC values for differentiating endoscopic inflamed segments from normal colon was calculated as2.135×10-3 mm2/s,with 95.7% sensitivity and 78.3% specificity,area under the curve（AUC）0.980.Conclusion：MRC combined with DWI has an accurate diagnostic value for the assessment of disease histological activity,extension and severity in patients with ulcerative colitis.
出处
《放射学实践》
北大核心
2016年第3期252-257,共6页
Radiologic Practice
基金
上海市卫生和计划生育委员会基金(20134265)
关键词
磁共振成像
溃疡性结肠炎
扩散加权成像
表现扩散系数
Magnetic resonance imaging
Ulcerative colitis
Diffusion weighted imaging
Apparent diffusion coefficient
作者简介
杨东（1974-），男，四川达州人，硕士研究生，主治医师，主要从事腹部影像诊断工作。
通讯作者：宋彬，E—mail：2088221853@qq．com
