Brink C, de Villiers J F, Lötter M G, van Zyl M
Department of Diagnostic Radiology, University of the Orange Free State, Bloemfontein, South Africa.
Br J Radiol. 1993 Aug;66(788):685-90. doi: 10.1259/0007-1285-66-788-685.
High image quality and low radiation levels are essential in mammography. This study investigates the effect of changes in processor temperatures and developing times on sensitometric findings. These findings were matched with the changes in the image quality during similar changes in the developing parameters. Temperatures ranging between 35 degrees C and 40 degrees C and developing times from 20 s and 50 s were investigated. Higher developing temperatures and increased developing times resulted in an increase in film speed and film contrast. A definite pattern of change could be demonstrated in film speed and film contrast during sensitometry. The same pattern of change could, however, not be demonstrated in the quality of phantom images under similar circumstances. The base plus fog level was not adversely affected. Sensitometric findings of film speed can be effectively used as an indicator of radiation exposure to the patient, but cannot be used to establish the developing parameters that will give the best image quality. Both these methods should be used to determine which processing variables should be used to obtain a combination of the best image with radiation as low as possible. Recommendations for optimum processing parameters are made for the films and processing chemistry investigated.
高图像质量和低辐射水平在乳腺摄影中至关重要。本研究调查了处理器温度和显影时间的变化对感光测定结果的影响。这些结果与显影参数类似变化期间图像质量的变化相匹配。研究了35摄氏度至40摄氏度的温度范围以及20秒至50秒的显影时间。更高的显影温度和更长的显影时间导致胶片感光度和胶片对比度增加。在感光测定过程中，胶片感光度和胶片对比度可以呈现出明确的变化模式。然而，在类似情况下，体模图像的质量却无法呈现出相同的变化模式。本底加灰雾水平未受到不利影响。胶片感光度的感光测定结果可有效用作患者辐射暴露的指标，但不能用于确定能产生最佳图像质量的显影参数。这两种方法都应用于确定应使用哪些处理变量，以获得最佳图像与尽可能低辐射的组合。针对所研究的胶片和处理化学药品，给出了最佳处理参数的建议。
