Regional heterogeneity in the brain's response to hypoxia measured using BOLD MR imaging

Blood oxygenation level-dependent (BOLD) magnetic resonance (MR) imaging is sensitive, in part, to the amount of paramagnetic deoxyhemoglobin in a vox el, This project was designed to determine whether there would be differenc es in the BOLD response between the hippocampus and other brain regions to acute hypoxia, R-2(star) was quantified using a multi-echo gradient-echo se quence. The pyramidal CA1 region of the hippocampus showed a reduced respon se to changes in arterial oxygenation relative to cortex and basal ganglia and white matter. This difference may relate to the relative hypoxia sensit ivity of the hippocampus. It also supports the premise that in functional M R imaging, the magnitude of the MR response to a stimulus may vary with the region of the brain. (C) 1999 Wiley-Liss, Inc.