Observer study involving laser-digitized versus CCD-digitized images

We compared laser- and CCD-digitized images for perceived image quality differences in a radiologist-observer study. Films of 50 two- and three-view studies (ankles, chests, c-spines, shoulders) were digitized on calibrated laser (Kodak Lumisys 75) and CCD (VIDAR SIERRA Plus) digitizers. Six radiologists independently compared digitized images on twin high-resolution monochrome monitors. Matching images were randomly presented on left/right monitors to support blinded comparisons. Observers scored image quality (for several diagnostic criteria) as "no different," left or right image "slightly" or "significantly" different. Of 7324 responses, 77.8% scored "no different" and 21.9% "slightly different" (5.9% favoring CCD, 16.0% favoring laser). In only 0.3% did observers score "significantly different." The Lumisys laser images were assessed as only slightly better than VIDAR SIERRA CCD images. Digitizer equipment-selection decisions can, therefore, be considered on the basis of price, reliability, support, ease-of-use, etc., rather than solely on the basis of image quality.