64排螺旋CT肝脏灌注成像探讨

Preliminary study of Hepatic Perfusion Imaging with 64-slice Spiral CT

目的利用64排螺旋CT对动物和人的肝脏进行CT灌注扫描,探讨CT灌注成像技术和灌注参数,寻求最佳检查方案。方法分别以动物和人作为检查对象并采用不同的CT灌注模式,动物组采用同层动态扫描灌注模式,人群组采用JOG灌注模式,使用双筒高压注射器注入对比剂和生理盐水,经肝脏CT灌注软件得出肝动脉灌注量(HAP),门静脉灌注量(HPP)、总灌注量(TLP)及肝动脉灌注指数(HAPI)等灌注彩图,在图像上分别测定相应的灌注参数值。结果主动脉TDC呈骤升骤降型;门静脉TDC呈速升速降型,出现较主动脉晚,幅度明显小于主动脉;正常肝实质TDC动脉期上升缓慢,门静脉期上升较快并达峰值;正常脾呈速升缓降型,强化峰值时间位于主动脉与门静脉之间,达峰值后缓慢下降。在图像上测得的HAP、HPP、HAPI分别为:兔(53．6±16．4)ml／min／100mg、(159±21．4)ml／min／100mg、(37．8±12．6)％;正常人(33．5±14．6)ml／min／100mg,(115．4±22．6)ml／min／100mg、(26．6±15．2)％。结论应用64排螺旋CT和专用肝脏灌注软件进行CT灌注成像能直观地反映肝脏血液动力学变化过程和血流灌注特征,是一种简单实用的方法,值得进一步临床应用和推广。

Objective To explore the optimum scan conditions, techniques and perfusion parameters of hepatic perfusion imaging （HPI） in human and New Zealand rabbits on 64-slice spiral CT examinations. Methods Four-slice sequence dynamic perfusion scans in 10 rabbits and the whole liver perfusion scans in 15 healthful men were performed. Contrast medium and normal saline were injected with double power injector. Hepatic arterial perfusion（HAP）, Hepatic portal perfusion （HPP）,Total liver perfusion （TLP） and Hepatic arterial perfusion index（HAPI） were calculated by special CT perfusion software. Results The ascending and the descending segments of aorta time density curve （TDC） appeared sharply. Portal vein TDC ascended and descended suddenly, and appeared later compared to the aorta TDC, and its amplitude was smaller than that of the aorta TDC. Normal liver TDC ascended slowly during arterial phase, and quickly ascended during portal vein phase. Normal spleen TDC showed a fast ascent and slow descent, the enrichment peak value time was between that of aorta and portal vein,and it descended slowly after the peak value. HAP, HPP, and HAPI were （53. 6 ± 16. 4）mt/min/lOOmg, （159± 21.4） ml/min/100mg and （37. 8± 12. 6）% in rabbits respectively, and （33.5 ± 14. 6） ml/ min/lOOmg, （115.4 ± 22. 6） ml/min/100mg and （26. 6±15.2） % in human respectively. Conclusion HPI with 64-slice spiral CT can directly reflect the hemodynamic changes and hepatic perfusion characteristic. It is a simple and practical method and worthy of clinical application and popularization.