Mondo Description Dandy-Walker malformation (DWM) is the association of three signs: hydrocephalus, partial or complete absence of the cerebellar vermis, and posterior fossa cyst contiguous with the fourth ventricle, presenting early in life with hydrocephalus, bulging occiput and posterior fossa signs such as cranial nerve palsies, nystagmus and ataxia.

Disease Ontology Description A cerebellar disease that is characterized by hypoplasia and upward rotation of the cerebellar vermis and cystic dilation of the fourth ventricle.