Magnetic resonance spectroscopy study of oxygen therapy in ischemic stroke.

BACKGROUND AND PURPOSE Recent studies suggest that normobaric oxygen therapy (NBO) is neuroprotective in acute ischemic stroke. METHODS We performed multivoxel magnetic resonance spectroscopic imaging and diffusion/perfusion MRI in patients with stroke treated with NBO or room air. Imaging was performed before, during, and after therapy. RESULTS Voxel-based analysis showed excellent correlation between apparent diffusion coefficient values, lactate, and N-acetyl-aspartate levels at all time points. Lactate decreased during NBO and increased post-NBO. N-acetyl-aspartate decreased in patients receiving room air but not in NBO-treated patients. CONCLUSIONS These data suggest that NBO improves aerobic metabolism and preserves neuronal integrity in the ischemic brain.