[Congenital and sporadic atrophy of the granular layer of the cerebellum with secondary pontocerebellar degeneration (author's transl)].

The primary interest of the case reported here of congenital atrophy of the granular layer of the cerebellum (Norman type) lies in the presence of an associated pontocerebellar degeneration, interpreted to be secondary (transsynaptic and retrograde) to the granular involvement and due to the length (42 years) of the evolution. Secondly, the sporadic character of this case is not in favor of a genetic disorder. By analogy with Herringham and Andrewes cat ataxia due to a perinatal virus infection (Margolis and Kilham), it can be hypothesized that granular cerebellar atrophy in man is related to an injury incurred at a "favorable" moment in histogenesis, that is, between the 3rd and 6th month of fetal life.