CT attenuation values of lung density in sarcoidosis.

Mean lung density (MLD), as determined by a chest computed tomographic sector method, was evaluated in 12 patients with sarcoidosis and diffuse interstitial lung disease. The results demonstrate that MLD in sarcoidosis was -610.9 +/- 57.3 Hounsfield units (HU), significantly different (p less than 0.001) from a control group MLD of -748.1 +/- 31.9 HU. There was also a significant inverse correlation between the forced vital capacity and total lung capacity in the sarcoidosis group. Our data suggest that a major factor determining MLD in a diffuse interstitial process such as sarcoidosis is pulmonary gas volume.