Technologic improvements in screen-film mammography.

During the past 20 years, many significant technologic improvements in mammographic x-ray equipment and screen-film-processing systems have occurred. Today it is possible to obtain mammograms with higher image quality at a significantly lower radiation dose, compared with mammograms dating back about 20 years. In this review article, clinical image comparisons and technical information--including x-ray spectra, limiting geometric resolution, sensitometric characteristic curves, modulation transfer function, and noise power spectra--are used to demonstrate technologic improvements in mammographic image quality.