Dandy Walker Malformation

Case Contribution: Prof Dr Azian Abd Aziz


  • A 3 years old girl with no previous medical records.
  • Suddenly fell off from her chair while having dinner.
  • Otherwise no neurological deficit and her GCS was full.
Non-contrast axial CT brain (a & b) and sagittal (c).

CT scan findings:

  • A large cerebrospinal fluid cystic space in the posterior fossa communicating with the 4th ventricle
  • Cephalad displacement of the hypoplastic cerebellum with elevation of the torcular herophili and
  • presence of hydrocephalus.

Diagnosis: Dandy-Walker malformation.


  • Dandy-Walker malformation is a congenital malformation that involves the cerebellum and fourth ventricle.
  • The ‘classic’ malformation is characterized by three criteria which are agenesis or hypoplasia of the cerebellar vermis, cystic dilatation of the fourth ventricle, and enlargement of the posterior fossa with high position of the tentorium.
  • About 70-90% of patients have hydrocephalus.
Author: radhianahassan