增强磁共振成像和扩散加权成像序列对肝转移瘤检出价值的比较

Comparison of Enhanced Magnetic Resonance and Diffusion-weighted Imaging for Detection of Hepatic Metastases

目的比较Gd-EOB-DTPA增强磁共振成像(MRI)容积动态多时相扫描(LAVA)与MR扩散加权成像(DWI)扫描对肝转移瘤(≤3 cm)的检出价值。方法回顾性分析16例肝转移瘤患者的MR资料,所用序列包括T1WI、T2WI,3D-LAVA增强MRI和b值为500 s/mm2的DWI。将所有患者分成2组并进行比较:A组(T1WI、T2WI和LAVA增强MRI),B组(T1WI、T2WI和DWI)。对于所有肝转移灶,采用受试者工作特征曲线(ROC)分析每组检查的诊断价值。结果共确定39个肝转移灶,A组的敏感性、特异性、Youden指数和ROC曲线下面积(AUC)分别为97.4%、88.2%、0.856和0.944,B组分别为82.1%、91.2%、0.733和0.834,其中,A组的AUC(P=0.040)和Youden指数(P=0.043)均明显大于B组。结论 Gd-EOB-DTPA增强MRI在检出小转移灶方面较DWI准确性更高。

Objective To compare the roles of Gd-EOB-DTPA-enhanced magnetic resonance imaging（MRI） using the liver acquisition with volume acceleration（LAVA） sequence and diffusion-weighted imaging（DWI） in the detection of hepatic metastases sized ≤3 cm.Methods We retrospectively analyzed the MRI data of 16 patients with hepatic metastases.All the sequences used included T1WI,T2WI,3D-LAVA,and DWI（b value=500 s/mm2）.All patients were divided into two groups based on the sequences：group A（T1WI,T2WI,and 3D-LAVA enhanced MR） and group B（T1WI,T2WI and DWI）.The hepatic metastases were evaluated by analyzing the receiver operating characteristic（ROC） curves.Results A total of 39 hepatic metastatic lesions were identified.The sensitivity,specificity,Youden index and the area under the ROC curve（AUC） were 97.4%,88.2%,0.856,and 0.944 in group A and 82.1%,91.2%,0.733,and 0.834 in group B.The ROC curves（P=0.040） and Youden index（P=0.043） in group A were significantly larger than in group B.Conclusion Gadolinium-EOB-DTPA-enhanced MRI has higher accuracy than DWI in the detection of small metastases.