双源CT肺动脉成像不同扫描模式图像质量及辐射剂量的对比研究  

Comparison of image quality and radiation dose of pulmonary angiography with different scanning protocols on dual source CT

作　　者：罗显丽 黄婷婷[1] 刘盼[1] 孙辉[1] 王梦[1] 李邦国[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：《实用放射学杂志》2016年第6期942-946,共5页Journal of Practical Radiology

基　　金：国家自然科学基金项目（81460265）.

摘　　要：目的 探讨双源CT肺动脉成像双能量扫描与普通扫描（单能量扫描）对图像质量及辐射剂量的影响。方法 临床怀疑肺栓塞并行炫速双源CT肺动脉成像单、双能量扫描患者各61例，按扫描方式不同分为A、B 2组，A组为双能量扫描（80/Sn140 kV），B组为普通扫描（Care kV选择输出管电压）。对2组图像进行图像质量评分及测量2组肺动脉CT值、空气标准差（背景噪声）并计算信噪比（SNR），同时对2组图像的辐射剂量进行对比分析，以P＜0.05为具有统计学意义。结果 2组图像质量主观评分2名观察者间一致性较好，Kappa分别为0.705、0.827，2组图像质量评分差异无统计学意义（P＞0.05）；A组右下肺动脉CT值高于B组，差异有统计学意义（P＜0.05），其余肺动脉的CT值差异均无统计学意义（P＞0.05）；A组图像噪声稍高于B组，SNR稍低于B组，差异无统计学意义（P＞0.05）；A、B 2组CT剂量指数（CTDIvol）、剂量长度乘积（DLP） 有效剂量（ED）分别为（6.13±1.09） mGy和（12.41±3.42） mGy、（172.49±41.35） mGy·cm和（332.16±115.65） mGy·cm 、（2.41±0.58） mSv和（4.65±1.62） mSv，差异具有统计学意义（P=0.000），A组CTDIvol、DLP 、ED较B组分别减少50.60%、48.07%、48.17%。结论 双源CT肺动脉成像双能量扫描（80/Sn140 kV）的图像质量与单能量扫描相近，X线辐射剂量较单能量扫描明显降低。Objective To compare the image quality and radiation dose of pulmonary angiography obtaining with dual-energy CT （DECT） scanning protocol and conventional scanning protocol （single-energy CT）. Methods 122 patients with suspected pulmonary embolism underwent flash dual-source CT pulmonary angiography with conventional scanning or dual energy CT scanning. All the subjects were divided into two groups according to the scanning type with 61 cases in each group（group A：DE,80/Snl40 kV;group B：single-energy,tube voltage was selected automatically by Care kV）. Two experienced radiologists assessed the image quality of the two groups and measured pulmonary artery CT attenuation and standard deviations of air（background noise）, and calculated the sig- nal-to-noise ratio （SNR）. Meanwhile, radiation exposure parameters （CTDIvol, DLP and ED） were compared between the two groups patients, and P〈0.05 was considered statistically significant. Results The agreement in evaluating image quality between the two observers was good with Kappa of 0. 705 and 0. 827 respectively. The image quality score of two groups has no statistically significant difference（P〉0.05）. CT attenuation in right lower lobe pulmonary artery were significantly higher（P〈0.05） in group A than group B, while the rest of the pulmonary arteries CT values did not differ significantly between the two groups（P〉0.05）. The noise of group A was more than that of group B and the SNR was slightly lower, and the noise and SNR had no statistically significant difference between group A and group B. The values of CTDIvol,DLP and ED in group A and group B were （6.13±1.09） mGy and （12.41±3.42） mGy, （172.49-±41.35） mGy ·cm and （332.16±115.65） mGy · cm, （2.41±0.58） mSv and （4.65±1.62） mSv respectively, with statistically significant differences（P=0. 000） ,and the values of CTDIvol,DLP and ED in group A was 50.60%, 48.07% ,48. 17% lower than that of group B respectively. Conclusion The use of dual

关 键 词：肺栓塞 计算机体层成像 血管造影术 图像质量 辐射剂量 

分 类 号：R563.5[医药卫生—呼吸系统] R814.42[医药卫生—内科学]