e-Speed电子束CT冠状动脉造影心电触发扫描时相与图像质量的关系

Electrocardiographic triggering phase and image quality in e-Speed EBCT coronary artery angiography

目的 总结冠状动脉e—Speed电子束CT血管造影（electron beam computed tomography angiography，EBCTA）检查结果，分析心电（ECG）触发扫描时相与图像质量的关系。方法 疑诊冠心病或健康查体来我院行冠状动脉EBCTA检查92例，以容积再现（volume rendering，VR）重建图像为评价主要依据，参考其他图像后处理结果，将EBCT冠状动脉造影图像质量分为6个等级（1～6分），与ECG触发扫描时相对照分析。结果 左冠状动脉主干和右冠状动脉近段显示图像质量最佳，平均分值为4．53和4．49，其次为左前降支近段和左旋支近段，平均分值为4．43和4．30。比较心动周期不同时相扫描，左冠状动脉主干和左前降支图像质量变异较小，而右冠状动脉和左旋支的图像质量变异较大，以收缩期末较好。结论 ECG触发扫描时相影响冠状动脉EBCTA图像质量，收缩期末触发的多时相扫描可兼顾冠状动脉各分支血管显示，提高诊断准确性。

Objective To summarize the examination results of coronary artery by electron beam computed tomography angiography （EBCTA） and analyze the relationship of electrocardiographic （ECG） triggering phase and image quality. Methods Ninety-two cases of suspected coronary artery disease or health screening were examined with e-Speed EBCT. Depending mainly on volume rendering （VR） , the images were divided into six grades （ scored 1 to 6 ） and analyzed in comparion with ECG triggering phase. Results The image quality of left main artery （LMA） and proximal right coronary artery （RCA） was best with average scores of 4.53 and 4. 49 respectively, followed by proximal left anterior descending artery （LAD） and proximal left circumflex （LCX）. Comparing the scans in different phases of cardiac cycle, image quality varied slightly in LMA and LAD but obviously in RCA and LCX. Conclusion Image quality of coronary artery EBCTA is related to ECG triggering mode. Muhiphase scan triggered in late systole will yield rather satisfactory images.