Dandy-Walker syndrome and associated anomalies.

This is a retrospective study of 28 infants and children with Dandy-Walker syndrome: 16 had a complete postmortem examination and 12 are currently being followed clinically. Eleven of sixteen in the first category had hydrocephalus; 10 of those 11 had other central nervous system malformations, and 6 also had visceral anomalies. Four of the five without hydrocephalus had complex cardiac malformations and other visceral anomalies whereas 1 died as a consequence of acute myelogenous leukemia. The 12 children still under surveillance manifest no clinical evidence of significant visceral or central nervous system malformation, although 1 has CT scan evidence of agenesis of the corpus callosum. The majority (9/12) of these children have normal intelligence although 40% have focal neurologic deficits or gait abnormalities and 60% have an abnormal EEG. Frequent association of other malformations and/or visceral anomalies in children with Dandy-Walker syndrome make it difficult to propose a unifying hypothesis relative to embryogenesis of the syndrome.