Dandy-Walker syndrome: presentation of the congenital malformation in an older patient.

Dandy-Walker syndrome, a congenital malformation of the hindbrain involving the cerebellum and the fourth ventricle, is a rare cranial abnormality that commonly occurs before the sixth or seventh week of development. It is usually diagnosed at birth or in early childhood; however, an occasional patient may first become symptomatic in adult life. A case of Dandy-Walker syndrome in a 58-year-old woman is reported because of the older age at presentation and relatively long asymptomatic period after birth.