管电压80 kVp时不同浓度对比剂CTPA图像质量的自身对照实验研究  

Oneself comparison study of CTPA imaging qulity with different iodine concentrations at tube voltage of 80 kVp

作　　者：全冠民[1] 马晶晶[2] 袁涛[1] 刘洋[1] 

机构地区：[1]河北医科大学第二医院影像科,河北石家庄050000 [2]河北省儿童医院超声科,河北石家庄055530

出　　处：《实用放射学杂志》2017年第6期648-651,共4页Journal of Practical Radiology

摘　　要：目的 探讨管电压80 kVp条件下保证兔CT肺动脉血管成像（CTPA）图像质量的最低碘对比剂浓度。 方法 新西兰大白兔10只，每只间隔3 d各行4次CTPA检查，碘对比剂浓度分别为350、300、270、250 mg I/mL。测量肺动脉主干及其同层面空气、左右肺动脉、上肺及下肺段以下肺动脉CT值，计算噪声（N）、对比噪声比（CNR）及信噪比（SNR），均以x±s表示，采用单因素方差分析进行比较，多重比较采用Dunnett-t检验。同时将肺动脉以段级肺动脉为界分为大血管和小血管，采用多个样本比较的Kruskal-Wallis H检验，编秩后行LSD-t检验进行多重比较。不同观察者间及同一观察者不同次测量（间隔1月）肺动脉CT值采用配对t检验，血管评分采用配对样本比较的Wilcoxon符号秩检验。 结果 不同对比剂浓度的CTPA均可显示6级肺动脉分支。270组肺动脉CT值［主肺动脉（687.17±167.83） HU］与最高的300组无明显差异［主肺动脉（848.68±185.03） HU］（t=-161.52，P=0.097）。270组CNR（6.3±1.30）及SNR（10.9±2.01）最高（t=-45.99，P=0.008；t=3.73，P＝0.088）,而N（62.84±6.05）最低（t=-11.09，P=0.016）。270组与其他3组间对于大血管评分无统计学差异（350-250组依次为3.91±0.35，3.90±0.38，3.90±0.42，3.86±0.42，H=6.588，P＝0.086）。270组对小血管评分低于350组及300组，但达到诊断要求（3.34±0.51）。 结论 管电压80 kVp时，兔CTPA检查采用270 mg I/mL碘对比剂较合适，可有效降低碘单位注射剂量。Objective To investigate the lowest concentration of iodine contast medium which can ensure CT pulmonary angiography （CTPA） imaging quality at tube voltage of 80 kVp. Methods Ten New Zealand rabbits underwent CTPA four times every three days with the iodine concentrations of contrast medium at each time were 350, 300, 270 and 250 mg I/mL respectively. The attenuation values of trunk pulmonary artery and air around the body on the same level, as well as right and left pulmonary arteries, and the pulmonary artery branches were compared among different groups. Meanwhile, image noise （N）, contrast-to-noise ratio （CNR） and signal-to-noise ratio （SNR） were calculated. All those data were analyzed with One-way classification ANOVA test. When multiple samples compared, Dunnett-t test was employed. The pulmonary arteries were divided into large and small arteries and assessed by multiple sample Kruskal-Wallis H test and analyzed with LSD t test when multiple samples compared. When the attenuation of trunk pulmonary artery of different viewers or the different times of the same viewer compared,paired t test was employed.Wilcoxon signed rank testing was employed for comparing the scores of pulmonary arteries among different groups. Results All the images of CTPA could demonstrate sixth- order branches of pulmonary artery. The attenuation of pulmonary arteries of the 300-group was the highest, however no statistical difference was found between 270 and 300-group [major pulmonary arteries：（687.17±167.83） HU,（848.68±185.03） HU,t=-161.52,P =0.097]. The CNR （6.3±1.30） and SNR [10.9±2.01） of the 270-group were the highest （t=-45.99,P=0.008; t=3.73, P=0.088）, and N （62.84±6.05） was the lowest （t=-11.09, P=0.016）. No statistical difference was found between 270-group and other 3 groups. And for the subjective scores of large arteries,no statistical differences （from 350-group to 250-group, 3.91± 0.35, 3.90 ! 0.38, 3.90±0.42 and 3.86±0.42, H= 6.588,P=0.086） were found. The scor

关 键 词：肺动脉 对比剂 计算机体层成像 

分 类 号：R322.121[医药卫生—人体解剖和组织胚胎学] R332[医药卫生—基础医学]