Xu, J Quantitative analysis of inhomogeneity in ventilation SPET. [electronic resource] - European journal of nuclear medicine Dec 2001 - 1795-800 p. digital Publication Type: Journal Article; Research Support, Non-U.S. Gov't ISSN: 0340-6997 Standard No.: 10.1007/s002590100649 doi Subjects--Topical Terms: AdultAgedCase-Control StudiesFemaleGraphiteHumansMaleMiddle AgedPulmonary Emphysema--diagnostic imagingPulmonary VentilationSmoking--physiopathologySodium Pertechnetate Tc 99mTomography, Emission-Computed, Single-PhotonVentilation-Perfusion Ratio