Kotre C J, Robson K J, Faulkner K
Regional Medical Physics Department, Newcastle General Hospital, Newcastle-upon-Tyne, UK.
Br J Radiol. 1994 Sep;67(801):856-9. doi: 10.1259/0007-1285-67-801-856.
A method for obtaining histograms of the frequency of occurrence of optical densities in mammograms has been implemented. Averaged optical density distributions were produced for approximately 50 screening mammograms at each of two centres using different film-screen and processing chemistry combinations. Additional measurements were made on films of two commercially available anthropomorphic breast phantoms. The results show that screening mammograms, on average, exhibit a strongly peaked optical density distribution which corresponds closely to the target optical density measured using the current recommended test protocol for automatic exposure control devices.
已经实现了一种获取乳房X光照片中光学密度出现频率直方图的方法。使用不同的胶片-增感屏和冲洗化学组合，在两个中心分别对大约50张筛查乳房X光照片生成了平均光学密度分布。还对两种市售的仿真人体乳房模型的胶片进行了额外测量。结果表明，筛查乳房X光照片平均呈现出强烈的峰值光学密度分布，这与使用当前推荐的自动曝光控制设备测试协议测量的目标光学密度密切对应。
