Fibrosing alveolitis: prognostic implication of ground-glass attenuation at high-resolution CT

To evaluate the prognostic implication of ground-glass attenuation at high-resolution computed tomography (HRCT) in assessing response to treatment in fibrosing alveolitis, the authors correlated HRCT findings with the improvement in pulmonary function, as represented by the increase in percentage predicted values on pulmonary function tests after corticosteroid therapy. Nineteen patients underwent HRCT before treatment and pulmonary function testing before and after treatment. The HRCT scans were reviewed by two independent observers. Areas of ground-glass attenuation were quantified subjectively by using a 0%-100% scale with 10% increments. The extent of ground-glass attenuation at HRCT was significantly correlated with improvement in diffusing capacity for carbon monoxide (r = .67, P = .0019), forced vital capacity (r = .71, P = .0007), and forced expiratory volume in 1 second (r = .64, P = .0034) after steroid treatment. These results suggest that ground-glass attenuation at HRCT is a good predictor of response to treatment in fibrosing alveolitis.