DETECTION OF RADIOGRAPHIC FINDINGS IN LUNG FIBROSIS USING STORAGE PHOSPHOR PLATES

The aim of this work was to examine the influence of the filter kernel size on the detectability of differing radiological findings in inter stitial lung disease. In 97 patients with confirmed pulmonary fibrosis chest radiographs were obtained with a film-screen system of speed cl ass 200 and with correspondingly exposed storage phosphorous plates. T he size of the filter kernel used for the image postprocessing varied between sigma 5 and sigma 70. The detectability of interstitial lung c hanges was evaluated independently by eight readers on the basis of a defined rating system. The results were analysed using multifactorial analysis of variance with Scheffe test at a significance level of p = 0.05. Small kernel sizes (S 5, S 10) combined with high edge enhanceme nt were only of benefit in the: imaging of septal lines, but reduced t he detectability of nodular and reticular structures. Good detail dete ctability of both micronodules and septal lines was obtained with a me dium kernel size of sigma 40. Storage phosphor radiography utilizing t he appropriate choice of postprocessing parameters provides equivalent image quality for evaluating interstitial lung changes compared with a modern film-screen technique.