Polymicrogyria in chromosome 22q11 deletion syndrome.

Central nervous system (CNS) dysfunction is a cardinal feature in 22q11 deletion. The underlying CNS abnormalities remain, however, unknown. We report unilateral hemispheric polymicrogyria in a child with 22q11 deletion presenting with hemiplegia and cognitive and behavioural disorders. This observation widens the spectrum of brain malformations associated with this genetic defect. It further suggests a relationship between the 22q11 deletion and disorders of cerebral gyration. It would therefore be interesting to look for neuronal migration disorders in patients with 22q11 deletion presenting neurological signs, and on the other hand to screen for 22q11 deletion in patients with isolated neuronal migration disorders