16层CT门静脉成像扫描参数及后处理方式的研究

16 detector-row CT: parameters and postprocessing of portography

目的:探讨16层CT门静脉成像扫描时间、层厚及后处理方式。方法:比较延迟时间为55s、65s两组的门静脉与肝实质CT值的差异;55s组分别以0.75、1.0、3.0mm层厚重建,获取最大密度投影(MIP)、多平面重建(MPR)两种方法的重建图像,根据评分比较成像质量。结果:55s组的门静脉与肝实质CT差值高于65s组,1.0mm层厚重建图像质量高于3.0mm组,但与0.75mm组比较差异无统计学意义,MIP法重建图像质量明显好于MPR法。结论:延迟时间55s,以1.0mm层厚用MIP方法重建即可获得高质量的门静脉图像。

Objective: To find a suitable delayed time, thickness and postprocessing way to display portal venous system. Methods: The density difference between the portal vein and liver of 55s and 65 s groups was compared. Using the raw data of 55s group, images were reconstructed with the thickness of 0.75 mm, 1.0 mm, 3.0 mm respectively. Then the imagings under MIP and MPR were compared. Results: The CT value between portal vein and liver of 55 s group was significantly higher than that of 65 s group(P<0.05). The reconstructed images of 1.0 mm was better than that of 3.0 mm, but had no significant difference with that of 0.75 mm(P>0.05). MIP reconstruction images were better than those of MPR. Conclusion: Used 55 s, and 1.0 mm thickness by MIP high quality portography can be got.