Inhalational lung disease

Inhalational lung diseases are among the most important occupational diseases. Pneumoconiosis refers to a group of lung diseases result from inhalation of usually inorganic dusts such as silicon dioxide, asbestos, coal, etc., and their deposition in the lungs. The resultant pulmonary disorders depend on the susceptibility of lungs; size, concentration, solubility and fibrogenic properties of the inhaled particles; and duration of exposure. Radiographic manifestations of pneumoconiosis become apparent several years after exposure to the particles. However, for certain types of dusts, e.g., silicone dioxide crystal and beryllium, heavy exposure within a short period can cause an acute disease. Pulmonary involvement in asbestosis is usually in the lower lobes. On the contrary, in silicosis and coal worker pneumoconiosis, the upper lobes are involved predominantly. For imaging evaluation of pneumoconiosis, high-resolution computed tomography (CT) is superior to conventional chest x-ray. Magnetic resonance imaging (MRI) and positron emission tomography (PET) scan are helpful in those with suspected tumoral lesions. In this essay, we reviewed the imaging aspects of inhalational lung disease.