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Flat-Panel X-ray Detector Based on Amorphous Silicon versus Asymmetric Screen-Film System: Phantom Study of Dose Reduction and Depiction of Simulated Findings

2003; Radiological Society of North America; Volume: 227; Issue: 2 Linguagem: Inglês

10.1148/radiol.2272010839

1527-1315

Ulrike Rapp-Bernhardt, Friedrich W. Roehl, R. C. Gibbs, Hagen Schmidl, Ulrich Krause, Thomas M. Bernhardt,

Radiation Detection and Scintillator Technologies

PURPOSE: To compare a large-area amorphous silicon flat-panel detector with an asymmetric screen-film system for the depiction of simulated patterns of interstitial lung disease, nodules, and catheters, as well as for evaluation of dose reduction. MATERIALS AND METHODS: Ground-glass, linear, miliary, and reticular patterns; nodules; and catheters were superimposed over an anthropomorphic chest phantom. Hard copies were generated at different dose levels (speeds: 400, 800, and 1,600) with a flat-panel detector and were compared with copies generated with an asymmetric screen-film system (speed, 400). Detection performance of eight radiologists was compared with a receiver operating characteristic analysis of 19,200 observations per pattern. A difference was significant with a P value of .05. RESULTS: There was no statistically significant difference between the flat-panel detector and the asymmetric screen-film system at the same speed (P > .05) and between the flat-panel detector at a speed of 800 and the asymmetric screen-film system at a speed of 400 (P > .05). The visibility of linear, miliary, and reticular patterns over lucent lung and of nodules smaller than 10 mm and catheters over obscured chest regions on copies generated at a speed of 1,600 with the flat-panel detector decreased, compared with the visibility of these features on copies generated with the asymmetric screen-film system (P < .05). CONCLUSION: The diagnostic performance of the flat-panel detector is comparable to that of the asymmetric screen-film system for depiction of all simulated patterns of interstitial lung diseases, nodules, and catheters at the same speed and offers the potential of dose reduction to a speed of 800. © RSNA, 2003