天津市数字化乳腺X射线摄影受检者剂量调查分析

Analysis of doses to glandular tissue from digital mammography in Tianjin

目的:了解天津市数字化乳腺X射线摄影的辐射剂量水平及其影响因素。方法:采用分层配额抽样方法选取天津市12家医疗机构的12台数字化乳腺X射线摄影设备374例数字化乳腺X射线摄影受检者,对照射体位[头尾位(CC)和侧斜位(MLO)]、乳房压迫厚度、管电压、管电流时间积(mAs)、靶/滤过等信息进行调查分析。结果:本调查的受检者年龄中位数为43岁,管电压(kV)中位数为29 kV,管电流时间积中位数为60.3 mAs,乳房压迫厚度中位数为48 mm,乳腺平均剂量(AGD)中位数为1.32 mGy。不同靶/滤过设备的乳腺平均剂量有所差异,变化趋势为Mo/Mo>Mo/Rh>Rh/Rh>W/Rh>W/Al,差异具有统计学意义(χ^(2)=885.90,P<0.05)。随着乳房压迫厚度的增加,乳腺平均剂量也呈增加趋势,且差异具有统计学意义(χ^(2)=31.58、8.56、76.13、118.47、24.09,P<0.05)。结论:天津市乳腺数字X射线摄影(DR)受检者乳腺平均剂量中位数为1.32 mGy,较广西和福州低,与北京和广东基本相当,低于全国乳腺DR摄影的乳腺平均剂量调查结果。今后应进一步加强对乳腺平均剂量影响相关因素的研究,保护受检者的健康和安全。

Objective To understand the level of radiation doses from digital mammography in Tianjin and the associated influencing factors.Methods The stratified quota sampling method was used for analysis of 374 digital mammography-examined individuals by using 12 digital mammography devices in 12 selected medical institutions.The examinations were carried out in terms of exposure positions[craniocaudal(CC)and mediolateral oblique(MLO)],compressed breast thickness,tube voltage,time product of tube current(mAs)and target/filter.Results The median age of the examined individuals in this survey was 43 years,the median tube voltage(kV)was 29 kV,the median tube current time product was 60.3 mAs,the median compressed breast thickness was 48 mm,and the median average glandular dose(AGD)was 1.32 mGy.The mean dose to the analyzed glandular tissue in the conditions of different target/filters varies in the descent order of Mo/Mo>Mo/Rh>Rh/Rh>W/Rh>W/Al,with the difference being statistically significant difference(χ^(2)=885.90,P<0.05).The mean dose to the glandular tissue increased with the increase in compressed breast thickness,and the difference was statistically significant(χ^(2)=31.58,8.56,76.13,118.47,24.09,P<0.05).Conclusions The median average glandular dose in Tianjin was 1.32 mGy.This level is lower than in Guangxi province and Fuzhou city,similar to that in Beijing and Guangdong province,and lower than the national survey result of average breast dose.The efforts should be dedicated to further strengthening the research on the related factors of the average glandular dose in order to protect the health and safety of the examined individuals.