Changes to the fractional anisotropy and mean diffusivity of in vivo rat brain measured at short effective diffusion-times

A sequence with oscillating motion-probing gradients was applied to investigate the restricted or hindered motion of water in in vivo rat brain tissue by observing changes to the apparent diffusion tensor, fractional anisotropy (FA) and mean diffusivity (MD) as the effective diffusion-time is decreased. Imaging was performed in a sagittal slice through the rat cerebellum and corpus callosum, which contain most of the white matter in the rat brain. Paired-t tests found significant differences in the FA of the corpus callosum and cerebellar white matter after the effective diffusion-time was decreased from 7.5 ms to 3.75 ms. Significant differences were also found for the MD in both grey and white matter. It is anticipated that normal and pathological in vivo tissue structure can be probed with this technique.19th Annual Meeting & Exhibitio