【摘要】 目的探讨心率对多层螺旋CT冠状动脉造影图像质量的影响和最佳重建相位窗的选择。方法回顾性分析67例患者16层螺旋CT心电门控条件下冠状动脉造影图像。按心率分成≤60次/min、61～70次/min、71～80次/min和≥81次/min分成第1～4组,将冠状动脉图像按伪影多少及血管连续性分为1～3分,评价心率与图像质量的关系,并优选出各组显示冠状动脉的最佳相位窗。结果对每位患者4条冠状动脉(右冠状动脉、左冠状动脉主干、左前降支、左回旋及图像质量进行研究。心率≤60次/min,可用于分析的图像占86.7%;心率61～70次/min,可用于分析的图像占62.5%;心率71～80次/min,可用于分析的图像占40%;心率≥81次/min,可用于分析的图像占12.5%。第1、2组与第3、4组间冠脉总的检查成功率有统计学差异(P<0.05)。第1组所有冠状动脉节段以75%相位窗为最佳;第2组冠状动脉节段以75%为最佳相位窗占89.5%,第3组左右冠状动脉以45%和75%为最佳相位窗分别占45%和55%,第4组全部冠状动脉节段以45%为最佳相位窗。结论心率对多层螺旋CT冠状动脉造影图像质量有重要影响;心率70次/min以下冠状动脉最佳相位窗通常为75%,心率71次/min以上时,应该以30%～90%多相位重建。更多还原

【Abstract】 Objective To evaluate the influence of heart rate on image quality of multi-slice spiral CT coronary angiography(MSCTA) and the optimization of image reconstruction windows.Methods Retrospectively ECG-gated MSCT coronary angiography were performed in 67 cases.The cases were divided into four groups by heart rate,group1 with heart rate less than 60 beats per minute(bpm),group 2 with heart rate 61-70 bpm,group 3 with heart rate 71-80 bpm and group 4 with heart rate over 81 bpm.The impact of heart rate on image quality of MSCTA and the optimization of image reconstruction windows were evaluated.Results 4 coronary(RCA,LM,LAD,LCX) segments were analyzed in each patients with regard to image quality.86.7%(112/128) of the coronary segments were sufficient for analysis in patients with heart rate less than 60 bpm,62.5%(55/88) with 61-70 bpm,40%(8/20) with 71-80 bpm and 12.5%(2/16) with heart rate over 81 bpm,respectively.There were statistically significances between every coronary segments of group 1 and 2,group 3 and 4(P<0.05).All coronary segments of group 1 were optimally visualized on the image reconstructed at 75% image reconstruction window of cardiac cycle;89.5% cases at 75% in group 2;for group 3,55% of coronary artery were best presented at 75% image reconstruction window,45% of coronary artery at 45%;All coronary segments of group 4 were optimally visualized on the image reconstructed at 45% image reconstruction window.Conclusion Image quality of MSCT coronary angiography is highly dependent on heart rate.Coronary artery is usually best shown at 75% image reconstruction window of cardiac cycle for those with heart rate less than 70 bpm.30%-90% image reconstruction should be performed when heart rate is over 71 bpm.更多还原