1Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States; 2Radiology, Duke University Medical Center, Durham, NC, United States; 3Pulmonary and Critical Care Medicine, Duke University Medical Center, Durham, NC, United States; 4GE Healthcare, Amersham, United Kingdom; 5Radiation Oncology, Duke University Medical Center, Durham, NC, United States
We demonstrate single breath-hold, 3D MRI of hyperpolarized 129Xe dissolved in the pulmonary tissues of humans. Dissolved 129Xe produces acceptable image quality because magnetization is efficiently replenished by diffusion from the airspaces. While ventilation images (3.03.0&15 mm3 resolution) of healthy volunteers were generally homogeneous, dissolved 129Xe images (12.512.515 mm3) displayed higher signal intensities in the gravitationally dependent portions slices. Dissolved 129Xe images of COPD patients were also heterogeneous but displayed different, less directional, patterns. These results suggest that dissolved 129Xe MRI is sensitive to the gravity-dependent distribution of pulmonary perfusion and possibly disease related redistributions of pulmonary capillary blood volume.