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Digital mammography is advancing into an arena where analog has long been the gold standard. Direct digital systems
may not be the favored solution for a particular site while computed radiography (CR) mammography, remains
unproven worldwide. This pilot study responds to the growing desire to acquire and display digital mammographic
images by exploring the acceptability of CR mammography. Images representing a range of breast tissue types were
collected from 49 subjects (17 screening; 32 diagnostic) at four clinical sites. Comparison views were collected on the
same breast, under the same compression, using automatic exposure control on state-of-the-art film systems followed by
CR. CR images were processed and printed to a mammography printer for hard copy feature comparison. Each image
pair in the study was evaluated according to 13 image quality attributes covering noise, contrast, sharpness, and image
quality in the overall captured images as well as in each of several particular breast regions (periphery and skin-line,
parenchyma and fatty tissue). A rating scale from 1 to 5 was used (strong preference for film=1, strong preference for
CR=5). Twelve experienced mammographers at four clinical sites scored a subset of the 49 cases for a total of 64 image
pair readings. There were 64 ratings for each of 13 image quality attributes for all cases and, an additional series of
scores (four or five attribute ratings) for each abnormality in the category of mass, architectural distortion and
microcalcification, for a total of 1069 scores. Based on the pilot study results, it was suggested that CR was equivalent
or preferred to conventional screen-film for overall image quality (38% scored 3; 46% scored >3), image contrast (27%
scored 3; 59% scored >3) and sharpness (28% scored 3; 50% scored >3). No preference was found when assessing
noise. This pilot study also suggested that diagnostic quality was maintained in assessing abnormalities for attributes
necessary to evaluate masses and microcalcifications as compared to screen-film.
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