脑CT静脉造影扫描时相及重建层厚的选择

目的选择脑CT静脉造影（CTV）的最佳扫描时相及重建层厚，以获得良好的脑静脉图像，提高脑静脉系统疾病的CT诊断水平。方法①进行同层动态增强扫描以获得大脑内静脉和上矢状窦时间密度曲线，选择脑CTV最佳延迟时间；②将1.250mm层厚扫描所获得原始数据重建0.625mm层厚，比较1.250mm、0.625mm两组层厚重建的三维血管图像质量，进行统计分析。结果本组脑CTV扫描的最佳延迟时间为36?s；采用0.625mm层厚重建的三维血管图像质量优于1.250mm层厚。结论采用36s延迟时间扫描和0.625mm层厚重建血管可以获得良好的脑CTV图像。

Delay time and slile thickness of CT venography of cerebral veins

Objective To investigate the optimal delay time and slice thickness of CT venography(CTV) of the head in order to get better images and to improve the diagnosis for cerebral venous system diseases.Methods Plane dynamic enhancement scanning was performed and a time-density curve of the internal cerebral vein and the superior sagittal sinus was produced at the workstation in order to get the optimal delay time of the cerebral CTV.The data obtained by a scanning thickness of 1.250 mm were retrospectively reconstructed with a slice thickness of 0.625 mm.Results Optimal delay time of CTV in the head was 36 s.Quality of images with a slice thickness of 0.625 mm was superior to that with a slice thickness of 1.250 mm.Conclusion Satisfactory CTV images of the head can be produced with an optimal delay time of 36 s and a slice thickness of 0.625 mm.