CONVENTIONAL FILM-SCREEN VERSUS COMPUTED STORAGE PHOSPHOR RADIOGRAPHY- SIMULATED MILIARY LUNG-DISEASE IN AN ANTHROPOMORPHIC PHANTOM

RATIONALE AND OBJECTIVES. In this experimental study, the authors exam ined whether laser printed hardcopies from digital storage phosphor ra diographs yield diagnostic performance equal to conventional film-scre en radiographs in the detection of simulated miliary disease, using a standardized object. METHODS. A commercially available anthropomorphic chest phantom was used for radiographic evaluation. Miliary disease w as simulated by superimposing one to four sheets of millet seeds on th e lungs, resembling a miliary disease pattern with varying degrees of detectability. An observer study (receiver-operating characteristic) w ith eight radiologists was conducted to compare the reader performance using hardcopies of computed storage phosphor radiography versus the conventional film-screen system, optimized for chest x-rays. The digit ally generated images were presented as a double-image hardcopy, with a conventionally adopted version and an edge enhanced image version. R ESULTS. When analyzed separately, one out of the eight observers perfo rmed slightly better using the conventional films. When treated as a g roup, analysis of the areas under the receiver-operating characteristi c curves demonstrated no significant difference in reader performance for each of the systems under investigation (t = 0.286). The Wilcoxon test could not prove a statistical difference. CONCLUSION. Storage pho sphor technology is a method that yields equal diagnostic performance as conventional film in evaluating miliary disease of the chest.