Asbestosis generally becomes manifest clinically 15-20 years after the onset of exposure. High resolution CT (HRCT) is more sensitive than both chest radiography and conventional CT for detecting parenchymal fibrosis (asbestosis) but a normal HRCT scan cannot completely exclude asbestosis. Given the long latency between asbestos exposure and asbestosis and given that no effective treatment is available to improve the outcome, screening and early detection of asbestosis is unlikely to allow any remedial action to be taken in the workplace or to confer any health advantage on asbestos-exposed individuals. Repeated imaging exposes the patient to radiation, which is not without risk. Therefore, while it is appropriate to obtain a baseline X-ray at the time of first assessment, for screening purposes, radiation risk outweighs the benefit of frequent chest X-rays. Radiation exposure would also be a concern for repeated CT scans.
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