基于年龄及头围建立儿童头颅CT辐射剂量管理的可行性研究  

A feasibility study of establishing radiation dose management for head CT examinations in children based on Age and head circumference

作　　者：张朋[1] 张晓军 张见 ZHANG Peng;ZHANG Xiaojun;ZHANG Jian(Department of Radiology,the Children’s Hospital of Nanjing Medical University,Nanjing 210000,China)

机构地区：[1]南京医科大学附属儿童医院放射科,江苏南京210000

出　　处：《实用放射学杂志》2024年第11期1867-1870,共4页Journal of Practical Radiology

摘　　要：目的比较容积CT剂量指数(CTDI_(vol))与基于水当量直径(DW)的体型特异性剂量估算值(SSDE_(DW))在儿童头颅CT检查辐射剂量评价上的差异,分析CTDI_(vol)、SSDE_(DW)与年龄(Age)、头围(HC)间相关性并建立回归方程。方法回顾性分析行儿童头颅CT平扫病例1297例,依照年龄分为<0.5岁、0.5~<1岁、1~<2岁、2~<5岁、5~<10岁、10~≤15岁6组,分别记录其Age、HC、CTDI_(vol),手动测量最中间扫描图像感兴趣区面积(AROI)及面积内平均CT值(CTROI),按照美国医学物理学家协会(AAPM)报告方法计算DW、转换因子(f)及SSDE_(DW)。比较CTDI_(vol)与SSDE_(DW)间差异,Pearson分析DW与Age、HC间相关性,建立CTDI_(vol)、SSDE_(DW)与Age、HC的回归方程,使用误差分析对回归方程进行准确性检验。结果1297例的头颅平均CTDI_(vol)为(9.22±1.63)mGy,SSDE_(DW)为(8.14±0.84)mGy,二者间差异有统计学意义(t=47.66,P<0.001);CTDI_(vol)、SSDE_(DW)与Age、HC有较好的拟合关系,其回归方程分别为:CTDI_(vol)[y=7.84x0.12(x=Age,R^(2)=0.88)]、[y=1.56 exp(0.035x)(x=HC,R^(2)=0.93)];SSDE_(DW)[y=7.49x0.06(x=Age,R^(2)=0.80)]、[y=3.20 exp(0.018x)(x=HC,R^(2)=0.83)]。回归方程平均误差分别为5.13%、3.73%、3.59%、3.36%,基于HC估算CTDI_(vol)、SSDE_(DW)更为准确。结论相较于CTDI_(vol),SSDE_(DW)衡量儿童头颅辐射更为准确。通过CTDI_(vol)、SSDE_(DW)与Age、HC间回归方程,有助于儿童颅脑CT检查诊断参考水平(DRL)的建立和应用,且HC比Age提供了更准确的辐射剂量估算。Objective To compare the differences in radiation dose evaluation between volume CT dose index(CTDI_(vol))and sizespecific dose estimate based on water equivalent diameter(DW)(SSDE_(DW))in pediatric head CT examinations,and to analyze the correlation between CTDI_(vol),SSDE_(DW)and Age,head circumference(HC)and establish regression equations.Methods A total of 1297 children with head CT plain scans were analyzed retrospectively and divided into 6 groups according to age<0.5 year old,0.5-<1 year old,1-<2 years old,2-<5 years old,5-<10 years old,10-≤15 years old,and their Age,HC and CTDI_(vol)were recorded,and the area of region of interest(AROI)and mean CT value of region of interest(CTROI)within area of the most intermediate scanned images were manually measured.DW,f and SSDE_(DW)were calculated according to the American Association of Physicists in Medicine(AAPM)reporting methods.The differences between CTDI_(vol)and SSDE_(DW)was compared,the correlation between DW and Age,HC was analyzed by Pearson,the regression equations for CTDI_(vol),SSDE_(DW)and Age,HC was established,and error analysis was used to test the accuracy of the regression equations.Results The head mean CTDI_(vol)was(9.22±1.63)mGy and SSDE_(DW)was(8.14±0.84)mGy in 1297 cases,and the difference between them was statistically significant(t=47.66,P<0.001);CTDI_(vol)and SSDE_(DW)had a good power function or exponential function fit with Age and HC,and their regression equations were:CTDI_(vol)[y=7.84 x0.12(x=Age,R^(2)=0.88)],[y=1.56 exp(0.035x)(x=HC,R^(2)=0.93)];SSDE_(DW)[y=7.49 x0.06(x=Age,R^(2)=0.80)],[y=3.20 exp(0.018x)(x=HC,R^(2)=0.83)].The average errors of the regression equations were 5.13%,3.73%,3.59%,and 3.36%,respectively.Estimating CTDI_(vol)and SSDE_(DW)based on HC was more accurate.Conclusion SSDE_(DW)is the most accurate indicator of head radiation dose in children than CTDI_(vol).The regression equations between CTDI_(vol),SSDE_(DW)and Age,HC helps to establish and apply the diagnostic reference level(DRL)of children’s head CT,

关 键 词：儿童 头颅 计算机体层成像 辐射剂量 回归模型 

分 类 号：R339.31[医药卫生—人体生理学] R816.1[医药卫生—基础医学] R814.41