Thin-Section CT Findings of Arc-Welders' Pneumoconiosis

OBJECTIVE To describe the thin-section CT findings of arc-welders' pneumoconiosis. MATERIALS AND METHODS Eighty-five arc-welders with a three to 30 (mean, 15)- year history of exposure underwent thin-section CT scanning. The extent of abnormalities detected was correlated with the severity of dyspnea and pulmonary function tests. For comparison, images of 43 smoking males (mean 25 pack-year) who underwent thin-section CT for other reasons (smokers' group) were also analyzed. RESULTS Fifty-four welders (63.5%) and six smokers (14.0%) showed positive findings. Predominant thin-section CT findings were poorly-defined centrilobular micronodules (30/54, 55.6%), branching linear structure (18/54, 33.3%), and ground-glass attenuation (6/54, 11.1%). In the smokers' group, poorly-defined micronodules were found in four patients, branching linear structures in one, and ground-glass attenuation in one. In welders, the extent of abnormalities seen on thin-section CT showed no significant correlation with the severity of dyspnea or the results of pulmonary function test. CONCLUSION Poorly-defined centrilobular micronodules and branching linear structures were the thin-section CT findings most frequently seen in patients with arc-welders' pneumoconiosis. Less commonly, extensive ground-glass attenuation was also seen.