[Chaos in pathogenesis of brain dysgenesis]

Various cortical dysplasias, such as agyria-lissencephalia, pachygyria, micropolygyria, neuronal heterotopia and so on, have become relatively common neuropathological findings among the children with intactable epilepsy and mental and/or physical handicap. Together with various environmental factors, gene abnormalities are recently increasing as a cause in various cortical dysplasias. However, details of the pathogenesis still remain unknown. Experimental studies using animal models indicated that inhibition of neuron production, disorders of neuron-glia and neuron-neuron contact, and plastic and unbalanced synaptogenesis subsequent to abnormal neuron production play an important role either separately or in combination in the pathogenesis of various cortical dysplasias.