使用256层螺旋CT全肝灌注法研究肝血管成像最佳延迟时间

Optimal Scan Delay Time Study of Hepatic Angiography Using 256-slice Spiral CT Perfusion Technique of The Whole Liver

目的:应用256层螺旋CT全肝灌注扫描,探讨肝动脉、门静脉、肝静脉最佳成像时间。材料与方法:对25例上腹部CT检查,肝功能正常者,行256层CT全肝灌注扫描。选取第一肝门层面腹主动脉、门静脉主干、肝实质及肝静脉二级分支层面的肝右静脉作感兴趣区(ROI),绘制时间密度曲线,计算腹主动脉、门脉主干、肝实质、肝静脉的平均强化峰值和达峰时间。结果:腹主动脉、门静脉主干、肝静脉、肝实质的平均强化峰值和达峰时间分别为499.6±80.58Hu,21.0±53.83s;283.28±41.97Hu,33.32±4.95s;220.62±41.24Hu,53.70±8.03s;220.62±41.24Hu,46.20±6.14s。结论:256层螺旋CT全肝灌注成像法可用于确定肝脏血管成像的最佳延迟时间,又能兼顾肝脏病灶的检查和诊断,是肝脏CT检查较完备的方法。该法显示正常人肝动脉、门静脉、肝静脉成像最佳扫描延迟时间95%的参考值范围分别是19.47-22.63s,33.28-37.36s,50.39-57.01s。

Purpose:To explore optimal scan delay time of the hepatic artery,portal vein,hepatic vein angiography,using 256-slice spiral CT perfusion technique of the whole liver.Materials and Methods:Twenty-five cases with normal liver were performed by 256-slice spiral CT perfusion scanner of the whole liver.At the level of the porta hepatis,the TDCs of regions of interest(ROIs) were drawn in the aorta,the portal vein,the right lobe of liver.The time-density curves of right hepatic veins were drawn at the secondary branch level of hepatic vein.The time to peak(TTP) and the peak value(PV) of all ROIs were recorded.Results:The peak value(PV) and the time to peak(TTP) of the aorta,portal vein,liver parenchyma and the right hepatic vein were499.6±80.58Hu,21.05±3.83s,283.28±41.97Hu,33.32±4.95s,220.62±41.24Hu,53.70±8.03s,220.62±41.24Hu,46.20±6.14s,respectively.Conclusion:256-slice spiral CT perfusion technique of the whole liver is a more comprehensive approach,which can determine the optimal delay time of hepatic angiography and maintain the examination and diagnosis of liver lesions.The method showed that during 95% reference range,the optimal scan delay time of normal hepatic artery,portal vein,hepatic vein angiography were19.47-22.63s,33.28-37.36s,50.39-57.01s,respectively.