PET Imaging of Regional 18F-FDG Uptake and Lung Function After Cigarette Smoke Inhalation

Cigarette smoke is thought to promote local lung inflammation that leads to lung dysfunction. Lung neutrophilic inflammation is known to result in increasedpulmonary uptake of 18F-FDG.Us-ing a sheep model of localized exposure to cigarette smoke, in this study we tested whether PET-imaged changes in regional intrapulmonary distribution of 18F-FDG uptake are related to changes in regional lung function as assessed with the infused 13NN-saline method. Methods: Five anesthetized, mechanically ventilated sheep were exposed to unilateral inhalation of smoke from 10 tobacco cigarettes while the contralateral lung was ventilated with smoke-free gas. Two hours after the exposure, regional gas content was measured from a transmission scan; regional ventilation, perfusion, and shunt were measured from the kinetics of 13NN-saline; and regional 18F-FDG influx constant (Ki) was calculated with the Patlak algorithm applied at a voxel