MRI常规检查联合扩散加权成像对不典型肝脓肿与肝内胆管细胞癌鉴别诊断的价值

The value of routine MRI combined with diffusion-weighted imaging in the differential diagnosis of atypical liver abscess and intrahepatic cholangiocarcinoma

目的探讨MR常规检查联合扩散加权成像(diffusion-weighted imaging,DWI)鉴别诊断不典型肝脓肿与肝内胆管细胞癌(intrahepatic cholangiocarcinoma,ICC)的价值。材料与方法回顾性分析19例ICC和19例不典型肝脓肿患者的MR图像,观察两组间病灶MR征象及病灶边缘实性部分的平均表观扩散系数(mean apparent diffusion coefficient,ADCmean)值及相对表观扩散系数(relative ADC,rADC)值的差异。采用独立样本t检验及χ2检验分析两组MR征象及ADC值的差异。结果 ICC与不典型肝脓肿在动脉期断环征、肝组织异常灌注、肝包膜的皱缩方面差异有统计学意义(P<0.05)。ICC病灶边缘实性成分ADCmean值为(0.84±0.14)×10^-3mm^2/s,rADC值为(0.70±0.12);肝脓肿边缘实性部分的ADCmean值为(1.04±0.10)×10^-3mm^2/s,rADC值为(0.95±0.05),两组间差异有统计学意义(P<0.001)。ADCmean值、rADC值ROC曲线下面积分别为0.832、0.964,ADCmean值以0.86×10^-3mm^2/s为截断值,鉴别两者的敏感度、特异度分别为100%和63.2%,rADC以0.83为截断值,鉴别两者的敏感度、特异度分别为100%和84.2%。结论 MR常规检查联合DWI有助于鉴别ICC与不典型肝脓肿。

Objective:To investigate the value of MR routine examination combined with diffusion-weighted imaging(DWI)in the differentiation of atypical liver abscess and intrahepatic cholangiocarcinoma(ICC).Materials and Methods:MR images of 19 cases of ICC and 19 cases of atypical liver abscess were retrospectively identified,observing the difference in MR signs of the lesion,the mean apparent diffusion coefficient value(ADCmean)and the relative apparent diffusion coefficient value(rADC)of the solid part of the lesion edge between the two groups.Differences in MR signs and ADC values between the two groups were evaluated with the t test and χ^2 test.Results:ICC and atypical liver abscess showed statistically significant differences in arterial phase broken ring sign,hepatic perfusion disorders,and hepatic capsular retraction(P<0.05).The ADCmean value and rADC value of the solid components at the edge of the ICC lesion were(0.84±0.14)×10^-3 mm^2/s and(0.70±0.12),respectively;the ADCmean value and rADC value of the solid components at the edge of the liver abscess were(1.04±0.10)×10^-3 mm^2/s and(0.95±0.05),respectively;the difference between the two groups was statistically significant(P<0.001).The area under the ROC curve of ADCmean value and rADC value were 0.832 and 0.964,respectively.Taking 0.86×10^-3 mm^2/s as the cut-off value,the sensitivity and specificity of ADCmean value in distinguishing ICC from atypical liver abscess are 100%and 63.2%,respectively.Taking 0.83 as the cutoff value,the sensitivity and specificity of rADC to distinguish between the two are 100%and 84.2%,respectively.Conclusions:MR routine examination combined with DWI can help to distinguish ICC from atypical hepatic abscess.