双源CT肺动脉成像双能量与单能量扫描的图像质量及辐射剂量  

Image quality and radiation dose of dual-energy scanning and single-energy scanning with dual-source CT in pulmonary angiography

作　　者：罗显丽 李邦国[1] 刘盼[1] 孙辉[1] 黄婷婷[1] 王梦[1] 张雪梅[1] 

机构地区：[1]遵义医学院附属医院放射科,贵州遵义563003

出　　处：《中国临床医学影像杂志》2017年第2期140-144,共5页Journal of China Clinic Medical Imaging

基　　金：国家自然科学基金项目(81460265)

摘　　要：目的:评估双源CT肺动脉成像双能量扫描与常规扫描(单能扫描)的图像质量及辐射剂量,探讨双源CT肺动脉成像合适的扫描方案。方法:收集临床怀疑肺栓塞并行flash双源CT肺动脉成像患者235例,按扫描方式不同将患者分为A、B、C 3组,A、B两组为双能量扫描,A组(77例,80/Sn140 kV);B组(80例,100/Sn140 kV),C组为常规扫描(78例,Care kV选择输出管电压)。测量3组肺动脉1~3级分支、背部肌肉CT值及背景噪声并计算信噪比(SNR)及对比噪声比(CNR),同时对3组图像进行图像质量评分,统计分析3组图像质量及辐射剂量,以P<0.05为差异有统计学意义。结果:A组双上叶肺动脉CT值与B、C两组比较,差异无统计学意义(P>0.05);B组与C组比较,差异有统计学意义(P<0.05),B组低于C组;其余肺动脉CT值3组间差异均无统计学意义(P>0.05)。A组背景噪声较其他两组高,相应的SNR及CNR低于其他两组(P<0.05)。3组图像质量均满足肺栓塞诊断要求,图像质量主观评分差异无统计学意义(P>0.05),两名观察者间一致性较好。图像质量主观评价良好(1~2分)的比例超过90%,且3组间差异无统计学意义(P>0.05)。A组CTDIvol、DLP、ED明显低于其他两组(P<0.05),其中ED较C组减少46.8%。结论:与常规扫描相比,双源CT肺动脉成像双能量扫描(80/Sn140kV)可以在图像满足诊断要求的同时明显减低X线辐射剂量。Objective： To evaluate image quality and radiation dose of dual-energy scanning protocol and conventional scanning protocol （single-energy scanning） with dual-source CT in pulmonary angiography and to investigate the optimal scanning protocols of dual-source CT pulmonary angiography. Methods： Two hundred and thirty-five patients with clinically suspected pulmonary embolism underwent flash dual-source CT pulmonary angiography were collected, and divided into three groups： group A（DE, 80/Sn140 kV）（n=77）; group B（DE, 100/Snl40 kV）（n=80）; group C（tubo voltage was selected automatically by Care kV）（n=78）. The CT attenuation values of pulmonary arteries（grade 1-3） and dorsal muscle, and background noise were measured. Corresponding signal to noise ratio （SNR） and contrast to noise ratio （CNR） were calculated. Meanwhile, two experienced radiologists assessed the image quality of the three groups. Image quality and radiation exposure were compared between groups, and P〈0.05 was considered statistically significant. Results： CT attenuation values in bilateral upper lobe pulmonary artery have no difference significantly （P〉0.05） between group A and group B/C. The value of the group B was lower than that of in group C（P〈0.05）, there was no significant difference（P〉0.05） in others compares. Compared to the other of two groups, image noise in group A were higher than others, and while its corresponding CNR and SNR for all measured pul- monary arteries were lower than others group （P〈O.05）. The image quality meet the diagnostic requirements for pulmonary embolism in all groups, and the image quality score of three groups has no statistically significant difference （P〉0.05） with good interobserver agreement. The image quality with good to excellent （1-2 score） grade of all subjective was more than 90%, and no significantly difference was between the groups （P〉0.05）. The values of CTDIvol, DLP, and ED were significantly lower in group A tha

关 键 词：肺动脉 辐射剂量 体层摄影术 X线计算机 

分 类 号：R322.121[医药卫生—人体解剖和组织胚胎学] R814.42[医药卫生—基础医学]