THE VULNERABLE IMMATURE CEREBELLUM: CONSEQUENCES FOR SURVIVORS FOLLOWING EARLY LIFE INJURY

The widespread availability of more sophisticated neonatal brain imaging techniques have facilitated the early and more accurate diagnosis of cerebellar injury. Survivors of preterm birth often demonstrate a spectrum of neurodevelopmental disabilities, reflecting the influence of early brain injury on their subsequent development. At school age, these children are more likely to be considered 'clumsy' and do less well academically. In addition to cognitive impairments and behavioral difficulties, these children manifest a constellation of long-term deficits, many of which are potentially referable to cerebellar injury, including impaired motor function such as fine motor incoordination, ataxia, and impaired motor sequencing.

Recent studies have demonstrated that cerebellar hemorrhage is an important complication of extreme premature birth and has been underrecognized in surviving preterm infants. Furthermore, an accumulating body of evidence is showing that preterm infants are at significant risk for cerebellar growth failure and impaired trophic interactions between the cerebellum and the cerebrum. The impact of early life cerebellar injury has far reaching global developmental consequences that extend well beyond the motor domain for survivors. It is noteworthy that both the lesion topography and neurodevelopmental outcome of cerebellar injury in the preterm versus term-born infant are distinctly different. The reasons for these differences are the focus of extensive investigation. Although the cerebellum has been known to play a central role in motor coordination, recent data suggest a key role of the cerebellum in the development of language, cognitive, and social functions. Further studies are needed to explore the developmental vulnerability of the cerebellum as well as the immature cerebellum's adaptive response following early injury. Moreover, accurate appraisal of structure-function outcomes is essential for appropriate counseling of parents, and to allow for more cost-effective models for targeting early intervention services and better resource allocation.