心电脉冲改良技术降低双源CT冠状动脉成像的辐射剂量

ECG-Pulsing Combined with Mindose Technique in the Radiation dose Reduction of Dual-Source CT Coronary Angiography

目的探讨心电脉冲(ECG-Pulsing)技术和Mindose技术在双源CT冠状动脉成像中降低辐射剂量的作用。资料与方法按照不同扫描方法随机将拟行双源CT扫描的136例可疑冠心病患者分为2组,标准组49例采用标准的ECG-Pulsing扫描,优化组87例采用优化后的ECG-Pulsing条件合并Mindose技术扫描。记录扫描后平均容积CT剂量指数(CT dose index volume,CTDIvol)和剂量长度乘积(dose length product,DLP),计算有效辐射剂量(effective dose,ED)。扫描图像质量采用双盲法评分。两组CTDIvol值、ED值和图像质量评分比较采用t检验。结果优化组CTDIvol值及ED值明显低于标准组(42.82±18.00mGy vs64.86±10.63mGy,11.72±5.16mSv vs17.26±3.36mSv),差异有统计学意义(t=-8.975、t=-7.575,P<0.01),平均剂量降低约33.41%。标准组和优化组冠状动脉各段图像质量平均评分比较,差异无统计学意义(3.56±0.38分vs3.60±0.24分,P>0.05)。结论双源CT冠状动脉成像时应用ECG-Pulsing合并Mindose优化技术,能在保证图像质量的前提下大幅度降低辐射剂量。

Purpose To evaluate the value of ECG-pulsing combined with Mindose technique in the radiation dose reduction of dual-source CT（DSCT）coronary angiography. Materials and Methods 136 cases of suspected coronary artery disease were divided into two groups randomly, standard group with standard ECG-pulsing（49 cases）, optimized group with ECG-pulsing combined with Mindose technique（87 cases）. CT dose index volume（CTDIvol）and dose length product（DLP）were obtained automatically, and the effective doses（ED）were calculated. The image quality was assessed by double-blinded scoring. t-test was used to analyze the data. Results Values of CTDIvol and ED in optimized group were obviously lower than those in standard group by 33.41% [（42.82±18.00）mGy vs（64.86±10.63）mGy,（11.72±5.16）mSv vs （17.26±3.36） mSv]. There was a statistical difference（t’=-8.975, t’=-7.575,P0.01）. The image quality scores of coronary segments of the two groups were 3.56±0.38 and 3.60±0.24, respectively, which showed no statistic difference （P0.05）. Conclusion ECG-pulsing combined with Mindose technique can reduce radiation dose remarkably with preserving the imaging quality in dual-source CT coronary angiography