摘要
目的:探讨体素内不相干运动扩散加权成像(IVIM-DWI)的定量参数在肛瘘活动性评估中的价值.方法:收集 75例肛瘘患者的术前MRI图像及临床资料,获取IVIM-DWI 序列(b=0、50、100、150、200、300、600、1 000、1 500、2 000 s/mm2)的定量参数,包括:真实扩散系数(D)、假扩散系数(D*)、灌注分数(f).以肛周疾病活动指数(PDAI)为诊断标准将上述患者分为活动性组(n=51)和非活动性组(n=24).比较两组患者IVIM-DWI 定量参数的差异,并采用受试者工作特征曲线(ROC)计算上述定量参数的诊断效能.结果:活动组和非活动组的D值分别为(0.27±0.20)×10-3 mm2/s和(0.52±0.18)×10-3 mm2/s,差异有统计学意义(P=0.000);D*值分别为 0.10(0.08,0.15)×10-2 mm2/s和 0.10(0.08,0.14)×10-2 mm2/s,差异无统计学意义(P=0.730);f 值分别为0.29±0.07 和 0.26±0.07,差异无统计学意义(P=0.710).ROC曲线分析显示D值预测肛瘘活动性的曲线下面积(AUC)为 0.900,敏感性和特异性分别为 86.3%、79.2%,最佳诊断阈值为 0.37×10-3 mm2/s.结论:IVIM-DWI定量参数的D值有助于术前无创性地评价肛瘘的活动性.
Abstract
Objective:To investigate the value of quantitative parameters of intravoxel incoherence motion diffusion weight-ed imaging(IVIM-DWI)in noninvasive preoperative prediction of anal fistula activity.Methods:Preoperative MRI images and clinical data of 75 patients with anal fistula were collected,quantitative parameters of IVIM-DWI sequence(b=0,50,100,150,200,300,600,1 000,1 500,2 000 s/mm2)were obtained.It includes diffusion coefficient(D),pseudo-diffusion coefficient(D*)and perfusion fraction(f).According to perianal disease activity index(PDAI),the patients were divided into active group and inactive group.The difference of IVIM-DWI quantitative parameters between the two groups were compared,and the diagnos-tic efficacy of the above quantitative parameters was calculated by receiver operating characteristic curve(ROC).Results:The D values of active group and inactive group were(0.27±0.20)×10-3 mm2/s and(0.52±0.18)×10-3 mm2/s respectively,and the dif-ference was statistically significant(P=0.000).The D* values were 0.10(0.08,0.15)×10-2 mm2/s and 0.10(0.08,0.14)×10-2 mm2/s respectively,with no statistical significance(P=0.730).The f values were 0.29±0.07 and 0.26±0.07 respectively,with no statisti-cal significance(P=0.710).ROC curve analysis showed that the area under the curve(AUC)of D value in predicting anal fistula activity was 0.900,the sensitivity and specificity were 86.3%and 79.2%respectively,and the optimal diagnostic threshold was 0.37×10-3 mm2/s.Conclusion:The D value of IVIM-DWI is helpful to noninvasively predict the activity of anal fistulas before operation.
维普
万方数据