目的 探讨对比剂优化注射在双 源CT(DSCT)在急性胸痛筛查中的价值。 方法 对72例急性胸痛患者行胸痛三联 筛查，随机分为两组：试验组(36例)， 采用对比剂分段优化注射；对照组(36 例)，采用全剂量注射；分别测量降主动 脉、肺动脉及冠状动脉平均强化CT值及 图像质量评分并进行两两比较。结果 全 部患者图像质量均能达到诊断要求，两 组间降主动脉、肺动脉及冠状动脉平均 强化CT值及图像质量评分差异无统计学 意义。结论 对比剂分段优化注射可以保 证图像质量，减少对比剂用量。

Objective To explore the value of contrast medium optimum injection using dual-source CT in acute chest pain screening. Methods Totally 72 patients who have acute chest pains were performed Triple-rule-out CT angiography. All patients were randomly divided into two groups. The trial group(n=36) was used with piecewise contrast injection, the control group(n=36) was used with full dose injection. The average contrast-enhanced CT Hounsfield unit values and the image quality scores of the descending aorta, the right pulmonary arteries and coronary arteries were compared between the two groups. Results All cases image quality met the diagnostic requirements. The average contrast-enhanced CT Hounsfield unit values and the image quality scores of target-arteries showed no significant difference between the trial and the control group. Conclusion The method of piecewise contrast injection can ensure the quality of the images, reduce the dose of contrast medium.