低电压、低碘剂量在冠状动脉CT血管造影中的效果分析  

Study on image quality of cardiac CT angiography with low tube voltage and contrast medium dose

作　　者：郑天辉[1] 林列兴[1] 沈衍富[1] 吴建满[1] ZHENG Tian-hui LIN Lie-xing SHEN Yan-fu WU Jian-man(Department of Radiology,Fujian Provincial Hospital, Fuzhou 350001, China)

机构地区：[1]福建省立医院放射科,福州350001

出　　处：《创伤与急诊电子杂志》2017年第1期10-13,9,共5页Journal of Trauma and Emergency(Electronic Version)

摘　　要：目的探讨低电压、低碘剂量在冠状动脉CT血管造影(CT angiography,CTA)中的应用价值。方法收集本院临床拟诊冠心病的78例患者,随机分为实验组和对照组,每组39例。实验组采用100k V扫描,注射速率用4.3ml/s,造影剂总量63ml,对照组采用120k V扫描,注射速率5.3ml/s,造影剂总量75ml,两组注射造影剂时间都是维持20秒。对图像质量进行客观评价,分别测量右冠主干、左冠主干、左前降支及左旋支近端CT值,在主动脉根部发出左前降支层面,在其中央密度均匀区域勾画大约1cm^2圆形感兴趣区,测量其CT值和SD(CT值标准差即客观噪声),然后计算信噪比SNR=CT/SD,并记录辐射剂量。由两位资深医师对图像进行主观评价并做出判断。结果 78例患者均顺利完成检查,两组图像质量均达到优良水平,两组各项评分数据相比P>0.05无显著差异。实验组的CT值高于对照组的CT值,但是两组信噪比相比差异无统计学意义(P>0.05)。实验组的辐射剂量要明显地少于对照组,两组辐射剂量相比差异有统计学意义(P<0.05)。结论低电压、低碘剂量情况下进行冠状动脉CTA扫描,不仅获得CTA图像质量完全可以满足临床诊断,而且可以降低辐射剂量。Objective o study the clinical application value of cardiac CT angiography with low tube voltage and contrast medium dose. Methods 78 cases of suspected coronary heart disease which underwent cardiac CT angiography were divided into experimental group（n=39） and control group（n=39）randomly. In experimental group, patients’ CT scan protocol was 100kV, 63ml contrast medium with 4.3ml/s injection velocity, while 120kV, 75ml contrast medium with 5.3ml/s injection velocity of CT scan protocol was adopted in control group. All patients’ image quality was then subjectively evaluated by two experienced radiologists. The CT attenuation of the right main coronary artery, left main coronary artery, left anterior descending coronary artery, and proximal left circumflex artery were acquired on the same cross section （the left anterior descending coronary artery extends down from the aortic root plane） with 1cm2 ROI（region of interesting） placed in the center of arteries. Each patients’ SNR and radiation dose were studied. Results The image quality of all patients of each group was excellent. There was no significant difference in image quality scores between these two groups（P〉0.05）. CT attenuation of coronary artery after contrast administration in experimental group was higher than that in control group, but there was no statistically significant difference in signal-to-noise ratio（SNR）of images between these two groups. Conclusion The image quality of cardiac CT angiography with low tube voltage and contrast medium dose for clinical diagnosis could be fully acquired, while radiation dose of patients was significantly reduced.

关 键 词：辐射剂量 低电压 低碘剂量 冠状血管 血管造影术 

分 类 号：R541.4[医药卫生—心血管疾病] R816.2[医药卫生—内科学]