肺动脉CT不同管电压及对比剂剂量的成像质量与辐射剂量比较

Comparison of imaging quality and radiation dosage of the different tube voltage of the pulmonary artery CT and contrast agent dose

目的对比分析肺动脉CT不同管电压及对比剂剂量的成像质量与辐射剂量，进而制定合理的CT肺动脉成像方案。方法选择接受检查的疑似肺动脉栓塞患者90例作为研究对象，随机分成两组，每组45例。两组分别应用不同的对比剂剂量和管电压，比较两组肺动脉节段的CT值、对比噪声比、信噪比、背景噪声水平、静脉伪影显示情况、肺动脉影像评分与辐射剂量。结果观察组和对照组在对比噪声比、信噪比、背景噪声水平、静脉伪影显示情况以及辐射剂量方面比较，差异有统计学意义（P〈0．05）；观察组和对照组在肺动脉影像评分与肺动脉节段的CT值方面比较，差异未见统计学意义（P〉0．05）。结论肺动脉CT成像选择较低对比剂剂量和管电压能够获取较好的肺动脉成像，不仅能够满足临床诊断的需求，同时可以减少对比剂用量和辐射剂量，可以在临床上推广应用。

Objective To contrastively analyze the imaging quality and radiation dosage of the different tube voltage of the pulmonary artery CT and contrast agent dose, so that for formulating the rea- sonable imaging protocol of the CT pulmonary angiography. Methods Ninety patients suspected with the pulmonary artery embolism were selected as the study objects. The patients were divided into two groups, with 45 cases in each group. The two groups were given different contrast agent doses and tube voltage, and then the segment CT value of pulmonary artery, noise ratio, signal to noise ratio, background noise level, display situation of vein artifact, grade of pulmonary artery imaging and radiation dosage were com- pared. Results There were significant differences in the noise ratio, signal to noise ratio, background noise level, display situation of vein artifact and radiation dosage between the two groups （ P 〈 0. 05 ）. There were no significant differences in the grade of pulmonary artery imaging and the CT value between the two groups （P 〉 0. 05）. Conclusions Lower contrast agent dose and tube voltage can get better CT pulmonary angiography, which is not only able to satisfy the requirements of the clinical diagnosis, mean- while able to reduce the contrast dosage and radiation dosage, so is worth promotion.