Wahl V H
Bayerisches Landesinstitut für Arbeitsschutz.
Rofo. 1987 Nov;147(5):563-6. doi: 10.1055/s-2008-1048699.
The usual measurement of the switchoff dose direct on x-ray film plane cannot be employed in mammography equipment without interfering with the switching device, because the chamber for monitoring the automatic exposure is situated behind the film holder and one cannot eliminate the film holder since it is an equipment-specific absorber. We are therefore presenting a method which allows to determine the switchoff dose on x-ray film plane via determination of the attenuating factor of the equipment (influenced by scattered radiation) and the phantom exit dose measured before the compression plate, the film holder having been pushed into position. The ratio of phantom influx to exit dose, standardised for a standard distance, serves additionally to easily recognise major deviations of the x-ray tube voltage from the adjusted value.
在乳腺摄影设备中，若不干扰切换装置，就无法直接在X线胶片平面上测量关机剂量，因为用于监测自动曝光的电离室位于胶片夹后方，且由于胶片夹是特定设备的吸收体，所以不能将其移除。因此，我们提出一种方法，该方法通过确定设备的衰减因子（受散射辐射影响）以及在推上胶片夹并压缩板之前测量的模体出射剂量，来确定X线胶片平面上的关机剂量。对于标准距离标准化的模体入射剂量与出射剂量之比，还可用于轻松识别X射线管电压与调整值的重大偏差。
