CAJ | 학술논문

目的通过优化个体化分类标准,探讨辐射剂量个体化基础上的低剂量冠状动脉CTA扫描实施方案.方法连续选取行冠状动脉CTA患者200例(A组),根据患者体质量指数(BMI),采用管电压120 kV,管电流150～ 300 mA(BMI＜ 18.5 kg/m2者),300 ～500 mA(18.5 kg/m2≤BMI＜25.0 kg/m2者),500 ～ 800 mA(BMI≥25.0 kg/m2者)进行扫描,扫描完成后分析管电流mA值与BMI、体表面积(Suf)、图像噪声(SD)的关系,并建立回归方程,依据方程推导速查表.再连续选取行冠状动脉CTA患者200例(B组),根据上述BMI与Suf分类的速查表,采用管电压100及120 kV,管电流按照速查表计算出的mA值,进行个体化低剂量扫描.统计学分析采用单因素方差分析和Kruskal-wallis H 检验.结果管电流mA值与BMI、Suf、SD的回归计算方程为:mA=17.984×BMI+169.149×Suf-2.282×SD-361.039.A组、B组扫描图像的SD值(A组:32.08±5.80；B组:28.60±4.47)、辐射剂量指数(CTDIvol)[A组:(41.97±11.37)mGy；B组:(33.18±10.07)mGy]、有效剂量值(ED)[A组:(10.91±3.07)mSv;B组:(8.83±2.72)mSv]差异均具有统计学意义(F值分别为43.45、63.71、49.07,P值均＜0.01),B组中图像噪声、辐射剂量值均小于A组.结论 BMI联合Suf作为分类标准,可进一步提高个体化的精确程度,在确保图像质量的同时合理降低辐射剂量.
목적 통과우화개체화분류표준,탐토복사제량개체화기출상적저제량관상동맥CTA소묘실시방안.방법 련속선취행관상동맥CTA환자200례(A조),근거환자체질량지수(BMI),채용관전압120 kV,관전류150～ 300 mA(BMI＜ 18.5 kg/m2자),300 ～500 mA(18.5 kg/m2≤BMI＜25.0 kg/m2자),500 ～ 800 mA(BMI≥25.0 kg/m2자)진행소묘,소묘완성후분석관전류mA치여BMI、체표면적(Suf)、도상조성(SD)적관계,병건립회귀방정,의거방정추도속사표.재련속선취행관상동맥CTA환자200례(B조),근거상술BMI여Suf분류적속사표,채용관전압100급120 kV,관전류안조속사표계산출적mA치,진행개체화저제량소묘.통계학분석채용단인소방차분석화Kruskal-wallis H 검험.결과 관전류mA치여BMI、Suf、SD적회귀계산방정위:mA=17.984×BMI+169.149×Suf-2.282×SD-361.039.A조、B조소묘도상적SD치(A조:32.08±5.80；B조:28.60±4.47)、복사제량지수(CTDIvol)[A조:(41.97±11.37)mGy；B조:(33.18±10.07)mGy]、유효제량치(ED)[A조:(10.91±3.07)mSv;B조:(8.83±2.72)mSv]차이균구유통계학의의(F치분별위43.45、63.71、49.07,P치균＜0.01),B조중도상조성、복사제량치균소우A조.결론 BMI연합Suf작위분류표준,가진일보제고개체화적정학정도,재학보도상질량적동시합리강저복사제량.
Objective To investigate the methods of reducing radiation dose in CT coronary angiography through optimizing individualized scan dosage protocol.Methods Two hundred patients (group A)underwent coronary CTA examination which was performed with fixed 120 kV and variable mA according to their BMI.The mA was set as 150-300 mA(BMI ＜ 18.5 kg/m2),300-500 mA (18.5 kg/m2 ≤ BMI ＜ 25.0 kg/m2),and 500-800 mA(BMI ≥ 25.0 kg/m2).When all examinations were finished,a linear regression was employed to analyze the correlation between mA and BMI,body surface(Suf),image noise(SD)respectively.The results of the analysis were used to formulate a regression equation,which was further used to establish a table list for quick search on how much mA that individualized coronary CTA scan would need.Another 200 patients(group B)enrolled for the individualized scan were scanned under new protocol that previous study established.The tube voltage was 100 and 120 kV.The tube current was variable according to the data in the table list.One-way ANOVA and Kruskal-wallis H test were used for statistics.Results Regression equation between mA and BMI,Suf,SD was:mA =17.984 × BMI + 169.149 × Suf-2.282 × SD-361.039.The SD(group A:32.08 ± 5.80,group B:28.60±4.47),dose index volume(CTDIvol)[group A:(41.97 ± 11.37)mGy,group B:(33.18±10.07)mGy],effective dose(ED)[group A:(10.91 ±3.07)mSy,group B:(8.83 ±2.72)mSv]had significant differences between the two groups(F =43.45,63.71,49.07 respectively,P ＜0.01 for all).The SD and ED results obtained in group B were better than those in group A.Conclusion Better performances were obtained when BMI combined Suf was used as a new individualized protocol than when BMI was used only,which means good image quality and lower radiation dosage in coronary CTA examination.