[Histopathologic features of glia in human epileptogenic brain lesions].

Focal cortical dysplasia is a common pathologic background observed in surgical specimens taken from patients with intractable epilepsy, where various types and degrees of dysplastic features were observed in various combinations. Prominent astrocytosis in the cortex and white matter was commonly evident. An ultrastructural investigation revealed dilatation of the postsynaptic dendritic spines and shafts in the cortex and features indicating the occurrence in the white matter of demyelination followed by remyelination. Thus, with regard to the epileptogenic lesions, although dysplastic changes constitute the pathogenetic basis, the overlapping subsequent degenerative process involving synapses, dendrites, and axons might contribute to the development of epileptogenic processes. Glia might also actively participate in the development of the pathogenesis of epilepsy.