New mammography screen/film combinations: imaging characteristics and radiation dose

Five types of film (Kodak OM, Kodak OM-SO177, Konica CM, Dupont Microvision, and Fuji MiMa) exposed in combination with seven different intensifying screens (Min R, Min R Medium, Siemens Orthox MA, Kyokka HR Mammo Fine, Agfa Gevaert Detail S (old and new), and Konica Monarch) were processed for either 90 sec (at 33.3 degrees C) or 3 min (at 35.0 degrees C). The films imaged a Computerized Imaging Reference System phantom with additional detail test objects placed on its surface to produce four groups of objects with which to evaluate resolution and contrast. For objects that tested resolution, the Kyokka HR Mammo Fine (Fuji) screen was statistically significantly superior; for objects that tested contrast, the Konica Monarch screen was statistically significantly superior. Extended processing did not affect Dupont and Kodak OM film as much as it affected the other films. It did affect contrast for the other films tested. The mean glandular doses from gridless exposures ranged from 32 to 80 mrad (0.32-0.80 mGy) over all film/screen/processing combinations for a 4.5-cm-thick test object. Several new film/screen combinations can provide images superior to the Kodak Min R/OM combination at a reduced radiation dose. The Kyokka HR Mammo Fine (Fuji) screen was found statistically superior in radiographic resolution of mammographic test objects and the Konica Monarch screen was found to be superior in defining contrast.