[Cerebellar hypoplasia in the newborn: association with respiratory control disorders and mental retardation].

Cerebellum malformations are frequently diagnosed since the advent of the neuroradiological studies (computed tomography, magnetic resonance imaging and ultrasonography). Cerebellar hypoplasia is found in association with a wide variety of neurologic and systemic disorders. Clinical picture in newborn may be different than in other periods of life. Two characteristics are interesting in neonatal period: their relation with abnormal respiratory control and mental retardation. The pathophysiology of cerebellar hypoplasia is uncertain, however experimental studies suggest than an abnormality of the Bergman glia may lead to the observed granulle cell layer deficiency in this malformation. It is tempting to speculate that a similar migrational abnormality in the cerebrum accounts for the intellectual impairment seen in some affected patients. Respiration is a complex neural function requiring precise coordination of numerous neural circuits. Cerebellar hypoplasia may be important in the pathogenetic mechanism of abnormal respiratory control due to cerebellar respiratory control disturbance. Also diaphragmatic dysfunction may occur in association with cerebellar atrophy. We report two newborns with cerebellar hypoplasia (vermis and hemispheres) associated with central respiratory and neurological dysfunction, and mental retardation.