钆塞酸二钠增强MRI肝胆期定量参数对良恶性胆道狭窄的鉴别诊断价值

The differential diagnosis value of quantitative parameters of hepatobiliary phase from Gd-EOB-DTPA enhanced MRI in differentiating benign biliary strictures from malignant strictures

目的探讨钆塞酸二钠(gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic acid,Gd-EOB-DTPA)增强MRI肝胆期定量参数对良恶性胆道狭窄的鉴别诊断价值。材料与方法回顾性分析143例行Gd-EOB-DTPA增强检查胆道系统狭窄患者的MRI图像,包括71例良性狭窄与72例恶性狭窄。计算肝胆期强化率相关参数[肝实质增强率(liver parenchyma enhancement ratio,LER)、肾髓质增强率(kidney medulla enhancement ratio,KER)、竖脊肌校正后的肝实质增强率(corrected parameter of liver parenchyma enhancement ratio,LERc)和竖脊肌校正后的肾髓质增强率(corrected parameter of kidney medulla enhancement ratio,KERc)],并对增强MRI肝胆期图像进行功能性肝脏影像评分(functional liver imaging score,FLIS)。比较胆道系统的良恶性狭窄在强化率相关参数、FLIS及相关实验室指标的差异性。采用受试者工作特征(receiver operating characteristic,ROC)曲线分析肝胆期定量参数鉴别良恶性胆道系统狭窄的诊断效能。结果胆道良恶性狭窄LER分别为73.4%(51.3%)、36.2%(32.0%),LERc分别为(39.3±25.4)%、(12.0±15.3)%。良性胆道狭窄FLIS为5.0(4.0)分,恶性胆道狭窄为2.0(1.0)分。上述参数差异均具有显著统计学意义(P<0.001)。LER对良恶性胆道狭窄鉴别曲线下面积(area under the curve,AUC)为0.769,LERc的AUC为0.818。FLIS对良恶性胆道狭窄鉴别AUC为0.810。联合LER及FLIS诊断的AUC为0.836,联合LERc及FLIS诊断的AUC为0.851。结论Gd-EOB-DTPA增强MRI的肝胆期肝实质强化率参数及FLIS对于良恶性胆道狭窄的鉴别具有较高价值,两者联合更能提高鉴别诊断效能。

Objective:To investigate the differential diagnosis value for differentiating benign and malignant biliary strictures using quantitative parameters of hepatobiliary phase(HBP)from gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic acid(Gd-EOB-DTPA)enhanced MRI.Materials and methods:The Gd-EOB-DTPA enhanced MRI images of 143 cases with biliary strictures were retrospectively analyzed,including 71 cases with benign strictures and 72 cases with malignant strictures.The relevant parameters of HBP enhancement ratio were calculated,including liver parenchyma enhancement ratio(LER),kidney medulla enhancement ratio(KER),corrected parameter of liver parenchyma enhancement ratio(LERc)and corrected parameter of kidney medulla enhancement ratio(KERc).Functional liver imaging score(FLIS)were calculated on HBP images from Gd-EOB-DTPA enhanced MRI.We compared the differences of relevant parameters of enhancement ratio,FLIS and related laboratory indexes between benign and malignant biliary strictures.Receiver operating characteristic(ROC)curve was used to analyze the diagnostic efficacy in differentiating benign biliary strictures from malignant strictures using HBP quantitative parameters.Results:LER of benign and malignant strictures was 73.4%(51.3%)and 36.2%(32.0%),respectively.LERc of benign and malignant strictures was(39.3±25.4)%and(12.0±15.3)%,respectively.The FLIS of benign and malignant biliary strictures was 5.0(4.0)score and 2.0(1.0)score,respectively.The differences were all statistically significant for above parameters(P<0.001).The area under the curve(AUC)of LER was 0.769 in differentiating benign from malignant biliary strictures,and the AUC of LERc was 0.818.The AUC of FLIS in differentiating benign from malignant biliary strictures was 0.810.The AUC of combining LER and FLIS was 0.836.The AUC of combining LERc and FLIS was 0.851.Conclusions:The parameters of hepatic enhancement ratio from HBP Gd-EOB-DTPA enhanced MRI and FLIS were both valuable in differentiating benign from malignant biliary strictures,with even better diagnostic efficiency on their combination.