[Quantitative analysis of pneumoconiosis in standard chest radiographs]

A computerized method to quantify and characterize interstitial diseases by using physical texture measures obtained from an analysis of the power spectrum of lung textures in digital chest radiographs was applied to Japanese standard radiographs of pneumoconiosis. Texture measures were determined from standard radiographs of silicosis, asbestosis, and other types of pneumoconiosis as well as chest radiographs of normal lungs. Our preliminary results indicated that the texture measures obtained from computer analysis corresponded closely with the standard categories of silicosis. However, there was no significant correlation between texture measures and the categories for asbestosis and other types of pneumoconiosis in terms of texture pattern. Japanese standard radiographs of pneumoconiosis are categorized according to the profusion of opacities, without reference to the size and shape of the opacities. Furthermore, in some films the size and shape of the opacities vary considerably within the same category. Therefore, it is considered that these characteristics of the standard films affected the results of our texture measures. It also considered that a large ROI and other texture measures are needed to characterize large opacities and mixed-shaped opacities of pneumoconiosis.