儿童头颅CT检查不同辐射剂量衡量指标差异性比较及相关性分析  

Comparison and correlation analysis of different radiation dose indicators in children's head CT examination

作　　者：张见 杨凤 张晓军 ZHANG Jian;YANG Feng;ZHANG Xiao-jun(Department of Radiology,Children's Hospital of Nanjing Medical University,Nanjing 210008,China)

机构地区：[1]南京医科大学附属儿童医院放射科,南京210008

出　　处：《医疗卫生装备》2024年第7期46-50,共5页Chinese Medical Equipment Journal

基　　金：江苏省政府留学基金项目(JS-2018-137)。

摘　　要：目的:比较容积CT剂量指数(volume CT dose index,CTDI_(VOL))及基于水当量直径的体型特异性剂量估计值(size-specific dose estimate based on water equivalent diameter,SSDE_(WED))在衡量儿童头颅CT辐射剂量中的差异性,并分析CTDI_(VOL)、SSDE_(WED)与曝光量、水当量直径(water equivalent diameter,WED)的相关性,以为临床检查中儿童头颅CT辐射剂量衡量提供参考。方法:回顾性分析2021年1—12月于某院进行头颅CT检查的1297例患儿的临床资料,根据年龄将患儿分为≤1个月组、>1个月~4岁组、>4~10岁组、>10~15岁组。记录患儿的曝光量、年龄、CTDI_(VOL)、剂量长度乘积,并计算WED、转换因子及SSDE_(WED)。比较CTDI_(VOL)与SSDE_(WED)的差异;建立CTDI_(VOL)、SSDE_(WED)与曝光量、WED的回归模型,并采用Pearson分析CTDI_(VOL)、SSDE_(WED)与曝光量、WED之间的相关性;对比国内诊断参考水平(diagnostic reference level,DRL)、欧盟DRL及本医疗机构诊断参考水平(local diagnostic reference level,LDRL)的差异。采用SPSS 25.0统计学软件进行分析。结果:患儿头颅CT的CTDI_(VOL)为(9.22±1.63)mGy,SSDE_(WED)为(8.14±0.84)mGy,CTDI_(VOL)较SSDE_(WED)高13.27%,差异有统计学意义(t=47.66,P<0.001)。CTDI_(VOL)、SSDE_(WED)与曝光量、WED均呈正相关关系(P<0.001);CTDI_(VOL)、SSDE_(WED)与曝光量、WED回归模型拟合性较强(R^(2)为0.58~0.99)。与国内DRL及欧盟DRL比较,LDRL均处于较低水平。结论:在儿童头颅CT辐射剂量衡量中,相较于CTDI_(VOL),SSDE_(WED)对辐射剂量的衡量更准确。同时定期对医疗机构的DRL值进行统计更新并优化检查参数,是减少辐射剂量的重要方式。Objective To compare the differences between volume CT dose index(CTDI_(VOL))and size-specific dose estimate based on water equivalent diameter(SSDE_(WED))in measuring head CT radiation in children and analyze the correlations between CTDI_(VOL)and SSDE_(WED)based on water equivalent diameter with exposure dose and water equivalent diameter(WED),so as to provide references for the measurement of head CT radiation of children.Methods Totally 1297 child patients undergoing cranial CT examination in some hospital from January to December 2021 were analyzed retrospectively,and were divided into four groups whose ages were not higher than one month,higher than one month to four years,higher than 4 years to 10 years and higher than 10 years to 15 years,respectively.The exposure dose,age,CTDI_(VOL)and dose length product of the children were recorded,and the WED,conversion factor and SSDE_(WED)were calculated.The differences between CTDI_(VOL)and SSDE_(WED)were compared;the regression models of CTDI_(VOL)and SSDE_(WED)with exposure dose and WED were established,and the correlations between them were explored with Pearson analysis;the differences were analyzed between the diagnostic reference level(DRL)in China,EU DRL and local DRL(LDRL).SPSS 25.0 was used for statistical analysis.Results The CTDI_(VOL)of the children's cranial CT was(9.22±1.63)mGy,and SSDE_(WED)was(8.14±0.84)mGy,and CTDI_(VOL)was 13.27%higher than SSDE_(WED),with a statistically significant difference(t=47.66,P<0.001).CTDI_(VOL)and SSDE_(WED)were both positively correlated with exposure dose and WED(P<0.001);the CTDI_(VOL)and SSDE_(WED)regression models with exposure dose and WED fitted well with R^(2) being 0.58 to 0.99.LDRLs were at a lower level when compared with DRLs in EU and China.Conclusion SSDE_(WED)behaves better than CTDI_(VOL)when used for measuring head CT radiation in children.Regular statistical updating of DRL values in medical institutions and optimization of examination parameters are important ways to reduce radiation doses.[Chinese

关 键 词：儿童头颅CT CTDIVOL SSDEWED LDRL DRL 辐射剂量 

分 类 号：R318[医药卫生—生物医学工程] R814.42[医药卫生—基础医学]