Fig. 2.

Population evaluation of emphysema using PDCM. (a) Illustration of superior (S), inferior (I), medial (M), lateral (L), posterior (P) and anterior (A) positions, and PDCM-based intensity projections on a sample right lung. (b) Average intensity (in HU) on PDCM-based angular and radial projections for MESA-COPD subjects with no emphysema (N = 205); (c) Average relative intensity differences, with respect to (b), on PDCM-based projections for MESA-COPD subjects with CLE-, PLE- and PSE-predominant emphysema (N = 37, 12 and 10 respectively).