Fig. 3From: The qualitative and quantitative high-resolution computed tomography in the evaluation of interstitial lung diseasesCT histogram analysis a showing total lung volume (TLV) and mean lung density (MLD) between threshold densities − 250 and − 910HU, b showing the percentage of the lung occupied by high attenuation areas (HAAs %) about 31.3%, and c showing the percentage of the lung occupied by low attenuation areas (LAAs %) about 22.6%Back to article page