双源CT冠状动脉成像中前瞻性与回顾性心电触发模式的比较

  目的  比较前瞻性心电触发序列扫描与回顾性心电触发螺旋扫描模式在双源CT冠状动脉成像中的图像质量及放射线剂量。  方法  将70例临床怀疑或已知冠心病的患者随机分为两组, 每组35例, 分别行前瞻性心电触发序列扫描和回顾性心电触发螺旋扫描冠状动脉CT成像, 对两种成像模式的图像质量及放射线剂量进行评价。  结果  两组患者的性别、年龄、体重指数匹配性良好, 差异无统计学意义(P > 0.05)。前瞻性心电触发序列扫描模式组和回顾性心电触发螺旋扫描模式组可评价的冠状动脉节段显示率分别为99.62%和99.62%, 两组间差异无统计学意义(χ²=0.000, P=1.000);两组图像质量评分分别为1.13±0.36和1.04±0.24, 差异有统计学意义(Z=-5.073, P=0.000);前瞻性心电触发序列扫描模式的放射线剂量为(3.47±1.00)mSv, 明显低于回顾性螺旋扫描模式的(14.28±1.81)mSv(P=0.032)。  结论  对于心律齐且心率≤ 70次/min的患者, 尽管前瞻性心电触发序列扫描的图像质量略差于回顾性螺旋扫描模式, 但两者可评价的冠状动脉节段显示率无明显差异, 而前者的有效放射剂量明显减少。

Comparison of Prospective and Retrospective Electrocardiogram-triggered Coronary CT Angiography Using Dual-source CT

Objective To compare the image quality and radiation exposure of prospective electrocardio- gram ( ECG) -triggered sequential and retrospective spiral acquisition coronary CT angiography by dual-source CT. Methods Seventy patients with suspected or known coronary artery disease were randomly divided into two groups ( n = 35 ) . Group A underwent prospective ECG-triggered sequential scan and group B underwent retrospective ECG-triggered spiral scan. The image quality and radiation exposure of both modes were evalua- ted. Results There was no significant difference in gender,age,or body mass index between the two groups ( P > 0. 05) . The rates of diagnostic coronary segments for group A and group B were 99. 62% and 99. 62% , respectively ( χ 2 = 0. 000,P = 1. 000 ) . The average image quality score was 1. 13 ± 0. 36 in group A and 1. 04 ± 0. 24 in group B,with significant difference between the two groups ( Z = - 5. 073,P = 0. 000) . The mean radiation dose of group A was significantly lower than that of group B [( 3. 47 ± 1. 00) mSv vs. ( 14. 28 ±1. 81) mSv,P = 0. 032]. Conclusion The prospective ECG-triggered sequential scan coronary CT angiogra- phy technique significantly reduces radiation dose without impairing the rates of diagnostic coronary segments when compared with the retrospective ECG-triggered spiral data acquisition in patients with a low and stable heart rate ( ≤70 bpm) . 【