Cerebellar micropolygyria in Fukuyama congenital muscular dystrophy: observations in fetal and pediatric cases.

Cerebeller micropolygyria in Fukuyama congenital muscular dystrophy (FCMD) was examined neuropathologically by three-dimensional reconstruction and immunohistochemistry in one fetal and two children's cases. In the children's cases, a complex columnar network of the molecular layer was mixed with clusters of the granular cell layers, often associated with central blood vessels. Although primitive, cortical dysplasia was also obvious in the fetal cerebellum at 23 weeks of gestation. Ectopic glial proliferation was less extensive than that in the cerebral cortex. It is suggested that leptomeningeal disruption, superficial proliferation of mesenchymal tissue and subsequent mixture of neuroglial and mesenchymal tissues, which may occur transiently during the fetal period in the developing FCMD cerebellum as well as in the cerebrum, play substantial roles in the development of cerebellar cortical dysplasia.