目的 探讨低管电压CT血管造影在心脏大血管患儿术前检查中的应用效果。方法 选择2018年4月—2019年4月接受CT血管造影检查的心脏大血管患儿82例,按照年龄、性别组间具有可比性原则,将其分为对照组与观察组。两组均给予固定电流150 mA扫描,其中对照组40例给予120 kV电压,观察组42例给予90 kV电压。对比两组图像的优良率、信噪比（SNR）、噪声比（CNR）、目标组织信号强度及背景噪声,并比较两组容积CT剂量指数（CTDIvol）、剂量长度乘积（DLP）及有效剂量（ED）。结果 两组CT图像优良率、SNR及CNR对比无显著差异（P>0.05）;观察组目标组织信号强度以及背景噪声较对照组高,CTDIvol、DLP及ED均较对照组低,差异具有统计学意义（P<0.05）。结论 低管电压CT血管造影应用于心脏大血管患儿的术前检查中,能够降低辐射剂量,且对图像质量的影响较低,值得临床推广应用。

Objective To investigate the application of low tube voltage CT angiography in the preoperative examination of children with cardiovascular malformation. Methods A total of 82 children with cardiovascular malformation who underwent CT angiography from April 2018 to April 2019 were selected and divided into a control group and an observation group according to age and gender. Both scanned at a fixed current of 150mA, the 40 patients in the control group were given a voltage of 120 kV, and the 42 patients in the observation group were given a voltage of 90 kV. The excellent rate of images, signal-to-noise ratio （SNR）, contrast-to-noise ratio （CNR）, signal strength of target tissue, and background noise, as well as CT dose index volume （CTDIvol）, dose-length product （DLP）, and effective dose （ED） between the two groups were compared. Results There were no significant differences between the two groups in the excellent rate of images, SNR, and CNR （P>0.05）. The signal strength of target tissue and background noise in the observation group were significantly higher than those in the control group, and the CTDIvol, DLP, and ED were significantly lower （P<0.05）. Conclusion Low tube voltage CT angiography applied in the preoperative examination of children with cardiovascular malformation can decrease radiation dose and have a less effect on image quality; therefore, it is worthy of clinical promotion and application.