Normal Development and Malformations of the Cerebellar Cortex

Abstract

The cerebellum is one of the first structures of the central nervous system that begins differentiation and one of the last to reach maturity. Neurogenesis of granular neurons is largely postnatal and cellular organization continues several months after birth. This protracted maturation causes susceptibility to developmental abnormalities. Such abnormalities encompass structural malformations and even cerebellar tumors. Current knowledge on the development of the cerebellar cortex is increasing. Cerebellar cortex development includes proliferation, migration, neuronal differentiation, guided axonal growth, neuronal map formation and synaptogenesis. These steps follow different timing and modalities compared to neocortex. The high resolution Magnetic Resonance (MR) improved the in vivo depiction of the cerebellar cortex and its developmental malformations. Correlation between neuroimaging and clinical findings as well as neurogenetic allowed practical classification of cerebellar malformations. The proposed morphology-based classifications appear incomplete and need continuous revision. In this review, we have followed a neuroradiological schema in order to reconcile previous classifications. Sviluppo normale e malformazioni della corteccia cerebellare