优化对比剂注射方案对冠状动脉CTA图像的影响

Effect of Optimized Contrast Agent Injection Method on Image Quality of CT Coronary Artery Imaging

目的探讨冠状动脉CTA时不同对比剂注射方案对图像质量的影响,优化注射方案。方法选取体重指数相似患者320例,分为A、B、C、D四组,进行冠状动脉CTA。A组对比剂采用双相注射方案,先期注射对比剂70 ml,而后注射生理盐水20 ml;B组采用双相注射方案,先期注射对比剂50 ml,而后注射混合液(生理盐水-对比剂1∶1)20 ml,C组采用三相注射方案,先期注射对比剂50 ml,第二时相注射混合液(生理盐水-对比剂1∶1)20 ml,而后无缝隙注射生理盐水20 ml;D组采用双相注射方案,先期注射对比剂50 ml,而后注射混合液(生理盐水-对比剂1∶1)20 ml,扫描时间较常规延迟5 s。比较四组冠状动脉CTA图像中冠状动脉三大分支和升主动脉(AO)CT值之间有无差异,比较四组上腔静脉、右心室硬化伪影发生率及室间隔显示率。结果与A组比较,B、C两组对比剂虽减少10 ml,但三组间AO及冠状动脉三大分支CT值比较无统计学意义(P>0.05),而D组CT值较A、B、C三组降低(P<0.05);B组上腔静脉、右心室硬化伪影发生率高于A、C、D三组(P<0.05),C、D两组室间隔显示率无统计学差异(P>0.05),但高于A、B两组(P<0.05)。结论采用三时相对比剂注射方案,可以有效降低对比剂用量,保证图像质量,清晰显示室间隔,为冠状动脉疾病的诊断提供影像依据。

Objective To investigate the effect of different contrast agent injection regimen on image quality in CTA imaging of coronary artery,and to optimize the injection regimen. Methods 320 patients with similar body mass index were selected and divided into A,B,C and D groups. Coronary CTA imaging was performed. A group of contrast agent using two-phase injection program,pre-injection of contrast agent 70 ml,and then injection of saline 20 ml; B group using twophase injection program,early injection of contrast agent 50 ml,and then injection mixture（saline：contrast-1∶ 1） 20 ml,C group using three-phase injection program,pre-injection of contrast agent 50 ml,the second phase injection mixture（normal saline ： contrast 1∶ 1） 20 ml,and then no saline injection of saline 20 ml; D group using two-phase injection program,pre-injection of contrast agent 50 ml,and then injection mixture（saline 1contrast 1∶ 1） 20 ml,scanning time was delayed by 5 s compared with the conventional. To compare the difference between the three branches of the coronary artery and the CT value of the ascending aorta（AO） in the four groups of coronary artery CTA images,and compare the incidence of intracavitary venous,right ventricular hardening artifacts and ventricular septal manifestations. Results Compared with group A,B and C were less than 10 ml,but there was no significant difference in CT value between AO and coronary artery（P〉0. 05）,while CT value of group D was higher than that of group A,（P〈0. 05）. The incidence of artifacts in the superior vena cava and right ventricular chamber of group B was higher than that in group A,C and D（P〈0. 05）. The difference was statistically significant（P〉0. 05）,but higher than that of A and B（P〈0. 05）. Conclusion The threephase contrast agent injection program can effectively reduce the amount of contrast agent,ensure the image quality,clear the interventricular septum,and provide the imaging basis for the diagnosis of coronary artery disease.