双源CT前置门控及回顾性门控扫描冠脉成像质量及辐射剂量对比

目的：评价双源CT前置门控与回顾性门控扫描冠状动脉成像的图像质量及辐射剂量的比较。方法：选取临床行冠状动脉CT造影检查者120例。60例行前置门控扫描，另60例行回顾性扫描。前置门控根据心率分为A（≤70次/分）、B（＞70次/分）两组，分别采用步进-点射式扫描和适应性扫描。回顾性门控根据心率分为C（≤70次/分）、D（＞70次/分）组，选取冠脉显示好的期相进行重建。采用4分法分析冠脉节段及图像质量，同时比较各组有效辐射剂量。结果：各组年龄、性别、BMI、平均心率、心率变异率、图像噪声均具有良好的一致性。对2801段冠状动脉进行分析，A～D组合格率分别为95.9%（702/732），83.8%（547/653），97.1%（720/742），86.9%（586/674），其中A组与C组、B组与D组合格率无统计学意义（P＞0.05）。A、B组有效辐射剂量分别为（3.28±0.23）mSv，（5.49±1.31）mSv，平均（4.35±1.44）mSv，C、D组分别为（15.29±0.55）mSv，（13.44±1.11）mSv，平均（14.51±1.32）mSv，分别降低78.55%和59.16%，平均降低70.03%。A、B组间辐射剂量存在统计学意义（P＜0.001）。结论：双源CT前置门控扫描能够对冠脉检查提供足够的诊断信息，并能够明显降低辐射剂量，因此能够用于可疑冠脉疾病的筛选。

Compare image quality,diagnostic accuracy and radiation dose of prospective and retrospective electrocardiogram gated dual-source computed tomography

Objective: To compare image quality,diagnostic accuracy and radiation dose of prospective and retrospective electro-cardiogram(ECG) gated dual-source computed tomography(DSCT).Methods: One hundred patients who underwent DS-CT coronary angiography(DS-CTCA) were enrolled in the study,60 were scanned by prospective scan and another 60 were analyzed by gated CT scan retrospectively.Sixty patients were divided into two groups according to their heart rate,receiving either step-and-shoot(heart rate less than 70bp...