['Radiologic morphology of emphysema proves useful in the selection of candidates for bilateral reduction pneumoplasty. We developed a simple morphologic grading system capable of identifying subsets of patients who had maximal functional improvement after unilateral or bilateral operation.', 'Fifty-two patients who underwent unilateral (n=34) or bilateral (n=18) reduction pneumoplasty were evaluated. Emphysema morphology was visually scored by digital roentgenograms and high-resolution computed tomography. In each lung, severity of emphysema (ES), heterogeneity (DHT) and hyperinflation (DHF) degrees, were assessed. Asymmetric ratio of emphysema (ARE) between the lungs was expressed as: higher ES/lower ES scores. Morphometric data were correlated with absolute preoperative-postoperative FEV(1) change (DeltaFEV(1)).', 'No difference was found between the unilateral and the bilateral group for ES and DHT. DHF was greater in the bilateral group (3.1 vs. 2.7, P=0.02) whereas ARE was greater in the unilateral group (1.29 vs. 1. 05, P=0.0001). Stepwise logistic regression extracted as best predictors of maximal DeltaFEV(1), ARE (odds ratio=238, Wald test P=0.04) in the unilateral group, and DHT (odds ratio=24, P=0.03) in the bilateral group. Unilateral group DeltaFEV(1) was greater in patients with ARE>/=1.3 (0.44 vs. 0.24 l, P=0.02). Bilateral group DeltaFEV(1) was greater in patients with DHT>1 (0.50 vs. 0.31 l, P=0. 03). No difference was found when comparing DeltaFEV(1) resulting from unilateral RP and ARE>/=1.3, and bilateral RP (0.44 vs. 0.41 l, not significant).'] Is morphologic grading of emphysema useful in the selection of candidates for unilateral or bilateral reduction pneumoplasty?