Miller-Dieker syndrome: a disorder affecting specific pathways of neuronal migration.

A patient with the typical craniofacial features and clinical course of Miller-Dieker syndrome (MDS) was found on autopsy to have focal pachygyria rather than lissencephaly. The brainstem and cerebellum were hypoplastic, but thalami and basal ganglia were normal. We believe that MDS is a syndrome in which multiple specific pathways of neuronal migration are affected selectively, such as migration to the neocortex, migration via corpus pontobulbare, and cerebellar migration. However, another migration pathway (via corpus gangliothalamicum) is spared.