CR乳腺摄影入射剂量的探讨

Discussion of mammary exposure doses in computed radiography

目的通过CR摄影,采用不同的自动曝光控制模式(QUICK、AEC、ACO),分析乳腺摄影入射剂量的不同,探讨有效降低健康妇女乳腺普查摄影中入射剂量的检查方法。方法抽查50份同一单位健康体检妇女连续3年的CR钼靶双侧乳腺检查,共600幅乳腺图像。同一女性3年的摄影条件均相同,分别采用不同的自动曝光控制模式,由同一技师进行规范化操作,在相同的观片环境下,用3MBARCO显示屏进行图像质量分析及其照射量比较。结果曝光指数在正常的1800～2500范围内,对比AEC、ACO两种曝光模式,用QUICK模式明显地降低入射剂量,同时通过后处理技术调整,乳腺图像更清晰,甲级片在75%以上。结论乳腺钼靶摄影要充分利用自动曝光控制模式,在保证照片质量同时,用低剂量原则达到降低乳腺的入射射量。

Objective To analyze the different incident dose by researching different automatic exposure control mode of computed radiography and to discuss examination method which can effectively reduce incident dose in breast screening of healthy women.Methods Totally three-year continuous 600 computerized mammography of 50 women with medical examination in the same company were randomly inspected.The same patient was relative to the same radiographic condition of three years and standardized operation of the same technician with different automatic exposure control mode.Analysed image-quality with 3M BARCO display screen and compared exposure dose in the same environmental condition of CR workstation.Results Exposure index ranged from normal 1800 to 2500.Comparing to AEC,ACO two exposure modes,QUICK mode obviously reduced incident dose and obtained clearer mammary images by post-processing workstation.The excellent film rate was above 75%.Conclusion Appropriate automatic exposure control mode should be chosen to obtain the best image-quality with lowest incident dose in mammography.