Digital mammography using storage phosphor plate technique - Optimizing image processing parameters for the visibility of lesions and anatomy

Digital mammograms from a storage phosphor plate system for general radiography were compared to conventional mammograms by means of visual grading analysis (VGA). For the digital images, image processing parameters were optimized and evaluated through observer preference analysis (OPA). The results of the VGA showed significantly better gradings for the conventional mammograms for parenchyma, linear structures, and cysts, and significantly better gradings for the digital mammograms for the skin surface. For calcifications, no significant difference was seen. For the OPA, contrast enhanced mammograms graded significantly best. Using standard image processing, the digital mammograms were considered as adequate for diagnosis in 49% of the cases, as uncertain in 20%, and as inadequate in 31%. However, the observers differed considerably in their gradings both in the VGA and in the OPA. (C) 1997 Elsevier Science Ireland Ltd.