关于16层螺旋CT冠状动脉成像最佳重建相位窗选择的探讨

目的探讨16层螺旋CT冠状动脉造影的最佳重建相位窗。方法32例健康受检者行16层CT冠状动脉成像检查，在6个相位窗（心动周期的R波后40％、50％、60％、70％、80％、90％）上对冠状动脉进行CT图像重组，对这6个时相的薄层图像进行最大密度投影、二维曲面重建、多平面重建和容积再现重建。结果每位受检者的4条冠状动脉分支（左冠状动脉主干、左前降支、左回旋支、右冠状动脉）分别用于图像质量分析。左主干在6个R—R时相均显示良好，左前降支、左回旋支在70％相位窗的图像质量最佳，右冠状动脉在80％相位窗的图像质量最佳，整体图像在70％相位窗的重组图像质量最佳。结论16层螺旋CT冠状动脉成像，应首先选择70％相位窗。选择最佳相位窗进行图像重建可以明显提高图像质量和工作效率。

Choice of optimal reconstruction window during 16-slice spiral CT coronary angiography

Objective To evaluate the optimal reconstruction window during 16-slice spiral CT coronary angiography（MSCTA）. Methods Thirty-two healthy subjects underwent MSCTA. Voluminal raw data were individually reconstructed at the starting points of 40%,50%,60%,70%,80% and 90% of intervals after the relative previous R waves.Thin images of six phases were acquired by MIP,CPR, MPR and VRT.Results Four coronary （LM,LAD,LCXmad RCA）segments were analyzed in image quality for each case.LM was well visual- ized in all 6 R-R phases.LAD and LCX were best visualized at 70% reconstruction window of the cardiac cycle,while RCA was best visu- alized at 80% reconstruction window of the cardiac cycle.MSCTA images acquired by volume rendering at 70% reconstruction window showed the optimal quality.Conclusion 70% reconstruction window of the cardiac cycle should be the first choice in MSCTA.Optimal reconstruction window can improve the quality of images and raise work efficiency obviously.