Presentation
Headache
Patient Data
A large posterior fossa solid mass that occupies and expands 4th ventricle measures about 4 x 3.2 x 4.7 cm in its various dimensions. It shows hypointense signal at T1WI, heterogeneous bright signal at T2WI, showing cystic areas of degeneration, and restricted diffusion in DWI. It is bulging through foramen of Magendie. It is associated with moderate supratentorial hydrocephalus with periventricular CSF transependymal permeation and surrounded by mild cerebellar edema.
Case Discussion
Medulloblastoma is the most common brain tumor in childhood. It occurs mainly in the posterior fossa and associated with obstructive hydrocephalus. Differentiating medulloblastoma from posterior fossa ependymoma is one of the radiological challenges, especially in the pediatric age group.