Subtle pulmonary disease: detection with computed radiography versus conventional chest radiography.

PURPOSE To determine the diagnostic efficacy of hard- and soft-copy computed radiographic (CR) images versus conventional screen-film images of the chest in the detection of subtle pulmonary abnormalities. MATERIALS AND METHODS Twenty observes compared 87 hard-copy and soft-copy CR images with hard-copy screen-film images. Of 87 test images, 45 (including two identical sets of 12 images to test intra-observer variability) were abnormal and 42 (including two identical sets of 12 images) were normal. Of the 45 abnormal images, 15 (including two sets of four identical images) showed subtle abnormalities, 15 (including two sets of four identical images) showed mild abnormalities, and 15 (including two sets of four identical images) showed obvious abnormalities. Soft-copy viewing provided three differently processed images of every radiograph. RESULTS No statistically significant differences in receiver operating characteristic analyses were found among hard-copy screen-film images, hard-copy CR images, and soft-copy CR images, even in the group with subtle interstitial abnormalities. CONCLUSION Hard-copy and soft-copy chest CR images are acceptable and available in place of screen-film images for primary interpretation of subtle interstitial lung diseases.