摘要
目的应用小剂量预注射法(Test Bolus)优化64层螺旋CT门静脉造影的最佳延迟扫描时间。方法60例无肝脏病变的检查者随机分成4组(A、B、C、D),每组15例。采用Test Bolus(15 ml、5 ml/s)在第一肝门层面测取门静脉的时间密度曲线(TDC),测其峰值时间,以Test Bolus峰值时间相应延迟4 s、6 s、8 s、10 s行腹部多层螺旋CT门静脉血管造影(MSCTP)检查。测量并分析4组门静脉主干及主要分支、肝脏实质最大CT值;原始数据采用最大强度投影、容积再现技术三维重建并评价其图像质量。结果Test Bolus(15 ml,5 ml/s)平均峰值时间24～32 s(95%可信区间)。C组门静脉的图像质量最好,观察细分支可达6～7级,门静脉1～4级主干强化较好。D组门静脉显影虽受到肝静脉轻度污染,但对肝脏表面门静脉边缘细小终末分支显影清晰、细腻。结论对比剂注射速率为5 ml/s时,门静脉延迟时间为小剂量预注射峰值时间延迟8～10 s(即注射对比剂后32～40 s)为最佳启动扫描时间。
Objective To optimize scan delay time of multi-slice spiral CT portal venography （MSCTP） using test bolus injection. Methods Sixty individuals with no hepatic diseases were randomly divided into 4 groups （A, B, C and D）. The time-density curves （TDC） of the portal vein （PV） were acquired by test bolus （15 ml, 5 ml/s） at the level of liver hilus. In the 4 groups, the MSCTP were delayed for 4, 6, 8 and 10 s according to the peak time of TDC, respectively. The maximum CT value of the portal vein and liver parenchyma were recorded. The maximum intensity projection （MIP） and volume rendering （VR） were employed for three-dimensional reconstruction and the image quality of the 4 groups was estimated. Results The average peak time of healthy individuals ranged between 24 and 32 s （95% confidence interval） by means of the test bolus （15 ml）. Group C （delay time of 8 s） had a much better image quality of the portal vain than the other groups, and the small branches of the portal vein （6th and 7th orders） were clearly visualized; the major portal vein branches （1 st to 4th orders） were also enhanced with sharp edges. Although the hepatic vein was also observed in the portal venous phase in group D, the details of the portal vein on the hepatic edge were distinct and well defined. Conclusion At the injection rate of 5 ml/s, the optimum scan time delayed is 8 to 10 s in normal individuals according to the peak time of the test bolus.
出处
《南方医科大学学报》
CAS
CSCD
北大核心
2008年第9期1573-1576,1578,共5页
Journal of Southern Medical University
基金
国家高技术研究发展(863)计划(2006AA02Z346)
广东省自然科学基金团队项目(粤科基办字6200171
7005198)
