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 examined whether laser printed hardcopies from digital storage phosphor radiographs yield diagnostic performance equal to conventional film-screen 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 was simulated by superimposing one to four sheets of millet seeds on the lungs, resembling a miliary disease pattern with varying degrees of detectability. An observer study (receiver-operating characteristic) with 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 digitally generated images were presented as a double-image hardcopy, with a conventionally adopted version and an edge enhanced image version.

RESULTS

When analyzed separately, one out of the eight observers performed slightly better using the conventional films. When treated as a group, analysis of the areas under the receiver-operating characteristic 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 phosphor technology is a method that yields equal diagnostic performance as conventional film in evaluating miliary disease of the chest.