Posterior fossa cyst differential diagnosis
see Intracranial cyst differential diagnosis.
Includes: a) cyst associated with Dandy Walker malformation. Cerebellar vermis is usually hypoplastic (or, less commonly, completely absent). Hydrocephalus often present
b) epidermoid
c) enlarged (mega) cisterna magna may mimic a cyst. No mass effect on cerebellum
d) cerebellar hemangioblastoma: often has an enhancing mural nodule
e) arachnoid cyst of posterior fossa: usually associated with mass effect on cerebellum
g) pilocytic astrocytoma of the cerebellum: usually has an enhancing mural nodule.