Early detection of ischemic injury during regional cerebral ischemia in cats

Diffusion- and T2-weighted MR imaging and P-31 and H-1 spectroscopy were evaluated in early ischemic injury in a cat stroke model. Diffusion-weighted images were acquired with large gradient b values of 1,413 sec/mm2. Within 1 hour following MCAO, the diffusion-weighted images showed significant hyperintensity in the gray matter and basal ganglia of the occluded side compared with normal side (40%-80%) and correlated well with the spectra. This hyperintensity exhibited slower diffusion compared with the contralateral hemisphere and is attributed to local increases in intracellular water. T2-weighted MR images showed no significant abnormality in the occluded hemisphere until several hours post-MCAO