Asbestos-related pleuropulmonary diseases: evaluation with low-dose four-detector row spiral CT.
PURPOSE: To evaluate the depiction of lung and pleural asbestos-related lesions with low-dose four-detector row spiral computed tomography (CT). MATERIALS AND METHODS: Eighty-three male workers with a mean duration of occupational exposure to asbestos of 18 years underwent CT as part of a medicolegal investigation. CT examination included low-dose multi-detector row spiral CT of the entire thorax, with reconstruction of contiguous 5-mm-thick images, and thin-section CT, which served as the reference standard for the detection of pleural and parenchymal asbestos-related abnormalities. Two main groups of abnormalities were identified: (a) pleural plaques and diffuse pleural thickening and (b) thickened interstitial short lines, curvilinear subpleural lines, ground-glass opacity with or without bronchiectasis, and honeycombing. The frequencies of the depiction of these abnormalities on the low-dose multi-detector row images and the thin-section images were compared by using the McNemar test. RESULTS: No significant differences were observed between the low-dose and thin-section CT images in the depiction of either (a) parietal pleural fibrosis consisting of pleural plaques (identified in 67 [81%] vs 65 [78%] workers, P =.157), which appeared mainly as thick, calcified pleural linear structures; or (b) features of parenchymal fibrosis, which consisted of various combinations of intralobular and septal lines (identified in 12 [14%] vs 13 [16%] workers, P =.564), subpleural curvilinear lines (identified in 10 [12%] vs eight [10%] workers, P =.157), and ground-glass opacity with (identified in six [7%] vs six [7%] workers) or without (identified in five [6%] vs three [4%] workers, P =.317) traction bronchiectasis. A honeycombing pattern was depicted on only the thin-section CT images (P <.001). Emphysema (identified in 26 [31%] vs 14 [17%] workers at low-dose and thin-section CT, respectively; P <.001) and noncalcified nodules (identified in 18 [22%] workers vs one [1%] worker, P <.001) were depicted significantly more frequently on the low-dose images than on the thin-section images. CONCLUSION: Low-dose multi-detector row spiral CT accurately depicts asbestos-related disease.