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 ra diography were compared to conventional mammograms by means of visual grading analysis (VGA). For the digital images, image processing param eters were optimized and evaluated through observer preference analysi s (OPA). The results of the VGA showed significantly better gradings f or the conventional mammograms for parenchyma, linear structures, and cysts, and significantly better gradings for the digital mammograms fo r the skin surface. For calcifications, no significant difference was seen. For the OPA, contrast enhanced mammograms graded significantly b est. Using standard image processing, the digital mammograms were cons idered as adequate for diagnosis in 49% of the cases, as uncertain in 20%, and as inadequate in 31%. However, the observers differed conside rably in their gradings both in the VGA and in the OPA. (C) 1997 Elsev ier Science Ireland Ltd.