应用80kVp低管电压前瞻性冠状动脉CTA探讨  

Feasibility study of 80kVp ultra-low dose scan protocol in prospective coronary CT angiography

作　　者：谭四平[1] 沈比先[1] 陈丽兴[1] 贾飞鸽[1] 汪春荣[1] 曾志斌[1] 薛水培[1] 刘康[1] 

机构地区：[1]广东医学院附属南山医院影像科,广东518052

出　　处：《放射学实践》2014年第3期300-304,共5页Radiologic Practice

摘　　要：目的:探讨在低体重指数(BMI)患者前瞻性冠状动脉CTA中使用80kVp管电压的可行性。方法:对84例临床疑似冠心病的患者行前瞻性冠状动脉CTA检查。将84例患者按BMI分为80kVp(BMI≤22kg/m2)和100kVp(22kg/m2<BMI≤25kg/m2)两组。脉冲曝光时间为200ms(心率≤65次/分)或380ms(心率>65次/分)。分析直径≥1.5mm的冠状动脉节段的图像质量,比较各组的图像质量及辐射剂量。结果:两组患者的年龄、身高、心率的一致性较好(P值>0.05)。80kVp、100kVp组的ED分别为(0.56±0.21)mSv、(1.43±0.58)mSv。两组的CT容积剂量指数(CTDIvol)、剂量长度乘积(DLP)、ED的差异均有统计学意义(P=0.000)。80kVp、100kVp组的合格图像分别为92.2%、91.8%。两组的图像质量评分、主动脉SNR及左、右冠状动脉主干CNR差异无统计学意义(P>0 05)。结论:80kVp的超低管电压前瞻性冠状动脉CTA可以应用于低BMI患者,图像质量足以满足诊断需要,辐射剂量显著降低。Objective：To investigate the feasibility of prospective coronary CTA using tube voltage of 80kVp in pa tients with low body mass index. Methods：Eighty-four patients with suspected coronary artery disease underwent prospec tive ECG-gated coronary angiography. All cases were divided into two groups based on BMI,one group was examined with 80kVp （BMI22kg/m2）,another group with 100kVp （22kg/m2 BMI25kg/m2）. If heart rates were less than 65 beats/ min,200ms was selected for pulse exposure time, otherwise 380ms were selected. The imaging quality of coronary artery segments whose diameter was larger than 1.5mm in the two groups was evaluated. The image quality and radiation dose were compared. Results：The age, height, and heart rate had a good consistency between the two groups （P〈0.05）. In group 80kVp and group 100kVp,the ED was （0.56 ±0.21）mSv, （1.43 ± 0.58）mSv, respectively. There were significant differ ences in CTDIvoI,DLP and ED between the two groups （P=0. 000）. Excellent or good image quality （score of 3 or 4） was achieved by 92.2%and 91.8% in group 80kVp and group 100kVp,respectively. In image quality scores,SNR of aortic and CNR of coronary trunk had no significant differences between the two groups （P〈0.05）. Conclusion：Prospective coronary CTA using tube voltage of 80kVp in patients with low body mass index can provide adequate coronary diagnostic informa- tion, and the radiation dose is significantly reduced.

关 键 词：体层摄影术 X线计算机 冠状动脉造影 管电压 辐射量 

分 类 号：R816.2[医药卫生—放射医学]