Digital chest imaging using a selenium detector. A simulated diffuse interstitial pulmonary disease detection study.

Abstract

To assess the diagnostic performance of a new digital chest imaging system based on a selenium detector in the detection of simulated diffuse interstitial pulmonary disease (DIPD). Diffuse interstitial pulmonary disease was simulated by superimposing plastic sheets containing small radio-paque objects (birdseed) on an anthropomorphic chest phantom. the number of sheets was varied from 0 to 4 to simulate the degree of pathology. Eighty conventional radiographs and 80 images with the selenium detector were obtained under comparable conditions. Six observers were asked to indicate the presence of DIPD using a five-level scale of confidence. The total 160 chest images were analyzed using receiver operating characteristic curves. There was no significant difference in detection performance between the conventional and the digital images (95% confidence interval). None of the observers assessed the diagnostic performance of the digital chest images as significantly different from that of the conventional system. The interobserver differences were higher than the differences between digital and conventional chest images.