肝硬化患者多层螺旋CT门静脉成像延迟时间优化

目的：探讨优化肝硬化患者16层螺旋CT门静脉成像的延迟时间。方法：30例肝硬化患者根据Child-Pugh分级分为A（Child A级15例）、B两组（Child B级12例和Child C级3例）,采用Smart Prep技术测定小剂量、常规剂量扫描时门静脉的强化峰值时间,比较差异。20例肝硬化患者随机分为C、D两组,分别根据小剂量预注射和经验延迟（55～65s）确定延迟时间,比较两组门静脉成像质量。结果：常规剂量门静脉成像时,A、B组门静脉强化峰值时间分别为52.07s、54.33s（P=0.098）,比小剂量门静脉峰值时间延迟7.93s、8.20s（P=0.701）。C、D组门静脉-肝脏最大密度差分别为67.27HU,46.18HU（P=0.000）,通过MIP后处理显示的肝内门静脉分支积分分别为4.83、3.85（P=0.023）,血管轮廓边缘积分分别为3.33、2.5（P=0.023）。结论：对比剂注射流率为3ml/s时,肝硬化患者门静脉成像延迟时间为小剂量预注射峰值时间延迟8s。

Optimization of the scan delay-time of multi-slice spiral CT portography in patients with liver cirrhosis

Objective：To optimize the scan delay time of multi-slice spiral CT portography （MSCTP）.Methods：30 patients with liver cirrhosis were divided into Group A （Child A 15 cases） and Group B （Child B 12 cases and Child C 3 cases） according to Child-Pugh liver function classification.The patients received 30 ml and 1.5ml/kg contrast media at a rate of 3.0ml/s in the CT examination using Smart Prep techniques.The peak times of portal vein were recorded and compared.20 patients with liver cirrhosis were randomly divided into Group C and Group D,and received respectively CTP using Smart Prep techniques and empirical 55~65s scan delay time,the image quality was estimated.Results：With 1.5ml/kg contrast media dose,the peak times of Group A and Group B were 52.07s and 54.33s （P=0.098） respectively,being 7.93s and 8.2s （P=0.701） later than with 30ml contrast media dose.The density difference between portal vein and hepatic parenchyma was significantly higher in Group C （67.27HU） than in Group D （46.18HU）（P=0.000）.By the maximum intensity projection reconstruction,the points of the branches and the vascular edges were 4.83 and 3.33 in Group C,better than in Group D,which were 3.85 and 2.5.Conclusion：At the injection rate of 3ml/s,the optimum scan delay time is 8s delayed in patients with liver cirrhosis according to the peak time of the test bolus.