Purpose of review: This review summarizes for the pediatrician the current understanding of normal cerebellar and brainstem development, and then discusses selected malformations to highlight advances in the area. The impact of prematurity on cerebellar growth and development is then examined. The important insights provided by recent neuroimaging and genetic advances are reviewed.
Recent findings: Previous areas of dispute are being addressed by advances in two major areas. Advanced neuroimaging studies during fetal and postnatal life are now providing important insights into the nature of normal and abnormal development of the brainstem and cerebellum. These powerful new techniques for defining morphology in vivo, together with major advances in genetics, are accelerating our understanding of genotype-phenotype relationships. Conversely, the ability to link early brain injury to subsequent cerebellar development has challenged previous understanding of the distinction between acquired and primary dysgenesis, presumed to be genetic in origin.
Summary: The synthesis of a rational and clinically useful classification of posterior fossa malformations has been elusive. Recent developments promise to resolve ongoing disputes that have delayed progress. However, these insights into disturbed structural development demand rigorous examination of their long-term functional significance and caution before their prognostic significance is applied clinically.