? DANDY WALKER VARIANT

CT scan brain showing dilatation of fourth ventricle ..
??dandy walker variant


Dandy-Walker malformation is a rare congenital malformation that involves the cerebellum and fourth ventricle.
Dandy-Walker malformation is characterized by

1. agenesis or hypoplasia of the cerebellar vermis
2. cystic dilatation of the fourth ventricle
3. enlargement of the posterior fossa

A large number of concomitant problems may be present, but Dandy-Walker malformation is recognized whenever these 3 features are found

Dandy-Walker complex is characterized by

1. an enlarged posterior fossa
2. a high position of the tentorium, with upward displacement of the lateral sinuses
3. torcular herophili associated with varying degrees of vermian aplasia or hypoplasia
4. a cystic dilatation of the fourth ventricle that nearly fills the entire posterior fossa.

Dandy-Walker variant consists of vermian hypoplasia and cystic dilatation of the fourth ventricle, without enlargement of the posterior fossa.