64层螺旋CT冠状动脉成像伪影产生及解决对策

目的探讨64层螺旋CT冠状动脉成像伪影产生的原因及处理对策。方法1000例临床怀疑或者已确诊为冠心病的患者，以回顾性心电门控技术行64层螺旋CT冠状动脉平扫和增强扫描，后处理行MIP、MPR及VRT重建，由两名经验丰富的影像科医生对冠状动脉伪影进行评估。结果1000例患者共显示冠状动脉节段13470段，其中存在伪影的有1920段，占14.25％，大部分为轻度伪影，发生率为13．65％，中重度伪影发生率为0．60％。产生伪影的原因中最常见的为呼吸运动，占总伪影发生率的70．77％，其次为心率，占总伪影发生率的10．77％。结论冠状动脉伪影产生的原因如下：呼吸运动、心率、心律变化、造影剂浓度、重建时相等。控制呼吸运动及心律不齐、降低心率、多时相重建等可以减少伪影产生及提高诊断准确率。

The Reason and Strategy of Artifact of Coronary Artery Imaging with 64-slice Spiral Computed Tomography

Objective To investigate the reason and strategy of artifact of coronary artery imaging with 64-slice spiral CT. Methods 1000 patients with diagnostic or suspected coronary artery disease underwent retrospectively ECG-gated 64-slice spiral CT. Images were reconstructed under different reformations of MPR, MIP and VRT. Image quality was assessed by two experienced radiologist. Results A total 13470 of 15000（89.80%） segments were visualized,the artifact segments were 1920,the incidence was 14.25%,the incidence of lower grade artifact was 13.65%, medium and heavy incidence added up to 0.60%. Breath movement caused most artifact,the other reason was heart rate. Conclusion The reason of artifact includes：breath,speed of heart, rhythm of heart, contrast concentration, rebuild percent and so on. Hold-breath and inhibit irregularity heart rhythmn,low-heart-rate,more rebuild percent lead to accurate diagnosis.