Correlation between somatosensory-evoked potentials and magnetic resonance imaging of focal cerebral ischemia in cats

Abstract

Serial measurements of somatosensory-evoked potentials (SEPs) and magnetic resonance imaging (MRI) were performed in 17 cats for 24 h after unilateral middle cerebral artery occlusion. Intravoxel incoherent motion (IVIM) imaging demonstrated ischemic cerebral injury 2 h post-occlusion in all cats, while T2-weighted imaging failed to show clear evidence of injury until 2-6 h. In the severely affected group of eight cats as determined by SEP criteria, ischemic injury evaluated by MR imaging was detected extensively in not only the basal ganglia but also the frontoparietal cortex including part of the somatosensory center. In contrast, in the mildly affected group of nine other cats, ischemic injury was limited to the basal ganglia with or without some involvement of the lower temporal cortex. The quantitative signal intensity ratios in the frontoparietal cortex were significantly greater in the severely affected group than in the mildly affected group, but showed no difference between them in the basal ganglia.