A rare genetic central nervous system malformation characterised by dysplasia of the superior cerebellum (especially the vermis), brainstem asymmetry, dysplasia of the basal ganglia and cortical irregularities with asymmetric abnormalities in gyral size and orientation, as well as varying sulcal depth, but without lissencephaly, pachygyria, or polymicrogyria. Clinically, patients present global developmental delay with motor development usually being more affected that speech. Variable features are abnormal eye movements including oculomotor apraxia, strabismus, seizures and behavioural problems. [from
SNOMEDCT_US]