Unappreciated agenesis of cerebellum in an adult: case report of a 38-year-old man.

An unexpected finding at autopsy of almost complete agenesis of the cerebellum in an apparently functional, mentally subnormal 38-year-old man who died as the result of an accidental electrocution is reported. The posterior fossa was normal in appearance despite nearly complete absence of the cerebellum. A number of syndromes of cerebellar atrophy or dysgenesis have been reported, but congenital agenesis is considered a very rare condition. It does not resemble most common cerebellar malformations or acquired conditions, especially in an adult, who apparently had reasonable motor and coordinative function. The relevant literature is reviewed.