肝硬化基础上肝癌肝血流变化功能CT灌注成像研究

目的对正常肝实质、肝硬化和肝硬化基础上肝癌患者的64层螺旋CT灌注成像进行分析,评价多层螺旋CT灌注成像对肝硬化基础上肝癌肝血流变化的诊断价值。资料与方法无肝脏疾病的30例作为对照组。实验组包括49例肝硬化疾病患者,其中27例确诊为原发性肝癌(HCC)。所有研究对象知情同意后,选择癌灶中心层面或肝门层面行CT灌注扫描,采用低剂量扫描:120 kV,60 mA,扫描范围为40 mm。以4～5 ml/s流率,按照1.0ml/kg体重用量静脉团注对比剂。在注入对比剂5 s后行50 s连续的扫描,360°旋转/s,5 mm层厚进行图像重组,矩阵大小512×512像素。利用去卷积数学模型获得与肝血流变化相关的灌注参数值:肝血流量(HBF),肝血容量(HBV),肝动脉灌注分数(HAF),肝动脉灌注量(HAP),门静脉灌注量(HPP)。对不同的感兴趣区进行三次灌注参数测量后取平均值进行灌注结果分析。感兴趣区包括:对照组的正常肝实质、癌灶边缘区、癌灶周围的肝实质和无癌灶的肝硬化肝实质。结果与对照组灌注参数比较,癌周围肝实质的HBF、HAP、HPP、HBV及癌灶边缘区的HBF、HAP、HPP有统计学差异(P<0.05)。与对照组相对应灌注参数比较,癌周的HAP、HPP及对照组的HBF、HAP、HPP有统计学差异(P<0.05)。与癌边缘区HAF对比,癌灶周围肝实质、对照组和无癌灶的肝硬化组均有统计学差异(P<0.05)。对照组和无癌灶的肝硬化组间灌注参数无明显差异(P>0.05)。结论 CT灌注成像能很好地反映肝硬化基础上肝癌的肝血流变化信息,为肝血流动力学变化的影像研究提供新的方法。

Assessment of Perfusion CT Imaging in the Hepatic Blood Flow of Hepatocellular Carcinoma Based on Cirrhosis

Objective To analyze the 64 slice CT perfusion of normal liver,liver cirrhosis and HCC based on liver cirrhosis,in order to assess its diagnostic value for hepatic blood flow of HCC in cirrhotic liver.Materials and Methods30 volunteers without liver disease(control subjects) and 49 patients with cirrhosis(study subjects)were enrolled,including 27 with hepatocellular carcinoma(HCC).All patients received CT perfusion study after their informed,central slice of tumor or hepatic portal were selected,scanning was carried out using a low radiation dose(120 kV,60 mA),volume coverage up to 40 mm.The rate of injection of contrast medium was 4-5 ml/sec with a dose of 1.0 ml/kg body weight.50 seconds of continuous scanning time set at 5 seconds after the injection of contrast material,1 second per 360°revolution,5 mm slice thickness image reconstruction,and a matrix size of 512×512 pixels were adopted.Deconvolution mathematical model was used to obtain perfusion parameters associated with changes in hepatic blood flow: blood flow(HBF),hepatic blood volume(HBV),hepatic arterial perfusion fraction(HAF),hepatic artery perfusion(HAP) and portal venous perfusion(HPP).Perfusion parameters were measured three times at each time point for each different region of interest: normal liver parenchyma,HCC rim,background liver parenchyma adjacent to HCC,liver cirrhosis without cancer.ResultsHBF,HAP,HPP,HBV in background liver parenchyma adjacent to HCC and HBF,HAP,HPP in tumor rim were different from those in control(P<0.05).HAP,HPP in background liver parenchyma adjacent to HCC and HBF,HAP,HPP in control were different from those in HCC rim(P< 0.05).HAF in background liver parenchyma adjacent to HCC and in control and in liver cirrhosis without cancer were different from that in tumor rim(P<0.05).There were no significant differences between control and cirrhotic liver without HCC(P>0.05).ConclusionPerfusion CT can reflect the information of liver blood flow about liver cancer based on liver cirrhosis,and can be used as a good method to study the liver hemodynamic changes.