[Diagnosis with high resolution computerized tomography of early asbestos-induced diseases]

This study was aimed at investigating the possibility of detecting lung and pleural asbestos-related lesions by means of conventional chest films and high-resolution Computed Tomography (HRCT) in a study population of asymptomatic workers of a shipyard factory in northwestern Tuscany, Italy. Thus, a blind study was carried out by two radiologists who reviewed 144 conventional chest films previously considered as negative by outside readers. Thirty-eight of 144 workers were selected, whose conventional films had been confirmed as negative, together with 34 more subjects with suspected pleural plaques or mild parenchymal involvement (ILO profusion score: 0/1). These 72 subjects were submitted to HRCT: 19 of them were negative, while in 33 cases pleural plaques were found; 7 workers exhibited parenchymal involvement alone, while in 13 both pleural and parenchymal alterations were found. HRCT findings were correlated with the duration of amosite exposure and the latency time since first exposure. Relative to conventional radiographs, the threshold of exposure and latency times allowing asbestos-related diseases to be demonstrated was markedly lower. Our study suggests that pleural and/or lung involvement in asbestos-exposed workers can be shown by HRCT before the onset of clinical symptoms or the appearance of pleural/parenchymal involvement on chest films. Moreover, the HRCT-detectable lung and/or parenchymal involvement appeared to be related to exposure and latency times, as in most of clinically-apparent asbestos-related lung diseases.