Influence of monitor luminance and tone scale on observer detection performance

The goal of this study was to determine the influence of adjusting monitor display parameters such as brightness and tone scale on observer diagnostic performance in older to determine what display settings are best for radiographic soft copy image display. Six radiologists viewed a series of 50 pairs of mammograms (craniocaudal and mediolateral views, right or left breast) on CRT monitors in two conditions. The images contained either a single subtle mass, a single subtle cluster of microcalcifications, or no lesion. In the first condition, the characteristic curve (tone scale) of the monitor was studied. Two curves were tested, one which was related to human perception and one which was typical for an unmodified CRT (default). In the second condition, display luminance was manipulated. Readers had to report on the presence of microcalcification clusters or masses and had to report their decision confidence using a 6-level rating scale. Monitor brightness (luminance) and tone scale can influence diagnostic performance to some degree. Whether the magnitude of these differences is important clinically needs to be further studied.