乳腺数字化X线摄影辐射剂量最优化探讨  

A study to optimize radiation dose of digital mammography

作　　者：朱宏[1] 陈克敏[1] 杨燕敏[1] 

机构地区：[1]上海交通大学医学院附属瑞金医院放射科,上海200025

出　　处：《诊断学理论与实践》2016年第4期430-434,共5页Journal of Diagnostics Concepts & Practice

摘　　要：目的：分析不同摄影条件下,乳腺数字化X线摄影图像质量和辐射剂量的变化,探讨在不影响图像质量的前提下,有效降低辐射剂量的摄影方法。方法：采用全视野乳腺数字化X线机,在不同摄影条件下[手动曝光模式（manual exposure control,MEC）、自动曝光模式（automatic exposure control,AEC）]对标准乳腺模体进行重复曝光测试,记录每种摄影条件下的体表入射剂量（entrance surface dose,ESD）和平均腺体剂量（average glandular dose,AGD）。由3名高年资影像科医师,按照美国放射学院乳腺模体影像评价标准对影像进行评分,并对ESD、AGD及图像质量评分进行统计学分析。结果：固定管电压（28 k V）时,ESD和乳腺AGD随着管电流的上升而上升;固定管电流（56 m As）时,ESD和乳腺AGD随着管电压的上升而上升,固定管电压和固定管电流这2组摄影参数改变的图像评分差异均无统计学意义（χ~2=0.434,P均〉0.05）。结论：在乳腺数字化X射线摄影检查中,MEC模式更适合个体化诊断,能够有效降低受检者的辐射剂量,达到剂量最优化。Objective： To analyze the image quality and radiation dose of digital mammography under different exposure conditions, and to find the effective method to reduce radiation dose without reducing image quality. Methods： Mammographic phantom was exposed using mammography X Ray machine with two target tubes at different exposure conditions： manual exposure control （MEC） and autonomic exposure control （AEC）, and the entrance surface dose （ESD） and average glandular dose （AGD） were recorded. According to the criteria proposed by American College of Radiology （ACR）, the images of mammographic phantom were reviewed and scored by three experienced radiologists. The SPSS 22.0 was used to analyze ESD, AGD and image quality scores. Results： At fixed tube voltage （28 kV）, ESD and AGD increased with the increasing of tube current. And at fixed tube current （56 mAs）, ESD and AGD increased with the increasing of tube voltage. There was no significant difference in image quality between the two exposure condition groups （x2=0.434, P〉0.05）. Conclusions： For digital mammography, MEC is suitable for individually adjusting exposure parameters, reducing radiation dose and helping the optimizing of dose.

关 键 词：乳腺数字化X线摄影 图像质量 辐射剂量 

分 类 号：R814.2[医药卫生—影像医学与核医学]