双源64层CT前瞻性门控冠状动脉成像图像质量评价及影响因素控制

目的评价双源64层CT前瞻性门控冠状动脉成像图像质量,分析前瞻性门控冠状动脉CT成像图像质量损害的因素,探讨在前瞻性门控技术下保证图像质量的方法。方法使用西门子公司Somatom Definition双源64排CT机,选取心率≤70次/分且憋气良好的50例患者进行前瞻性门控低剂量冠状动脉CT扫描(A组);同时随机选择同时期拟行CT冠脉成像的100例病人行回顾性门控冠状动脉CT扫描,根据心率分为B组50例(心率≤70次/分),C组50例(心率>70次/分)。对比分析各组冠状动脉CT成像图像质量评分差异;分析图像质量损害的因素。结果三组中图像质量积分3分以上的均在98%以上,全部病例图像质量均能满足诊断要求。三组间图像质量积分差异无统计学意义。图像质量影响因素主要包括步进台阶伪影、运动伪影、心率变化所致的错录伪影、血管对比不良。结论前瞻性门控冠状动脉CT成像图像质量能够满足诊断需求,通过对图像质量影响因素的科学合理控制可提高图像质量。

Image quality Evaluation on DSCT(64 slice) Prospective ECG-triggering Coronary CT Angiography

Objective To analyze the influential factors of the image quality in prospective ECG-triggering for coronary CT angiography,and to explore the methods to get good imaging in prospective ECG-triggering technique.Methods 50 cases with heart rate less than 70 times per minute and breath-holding good performed prospective ECG-triggering for coronary CT angiography(A group).At the same time,100 cases were selected randomly and performed retrospective ECG-triggering for coronary CT angiography.100 cases was divided into two control groups(B,C group) based on different heart rate.The difference of imaging quality among groups were analyzed.Results More than 98% cases had image quality score above 3.All cases could meet the demand for diagnosis.There was no significant difference among the three groups in image quality score.Influence factors of image quality mainly included the step artifact,motion artifacts,heart rate changes caused by fault recording artifacts and vascular poor contrast.Conclusion The image quality of prospective ECG-triggering for coronary CT angiography can meet the demand of diagnosis.Scientific and reasonable control on the influence factors of image quality can improve the image quality.