Case 077

History/Physical

History/Physical:

4-year-old right-handed female.

Three month history of headache and gait ataxia.

There is a solid cystic lesion in the right cerebellar hemisphere.

There is significant mass effect in the posterior fossa. There is compression of the brainstem (*) and tonsillar herniation (arrow).

The solid component enhances (*). The cyst has smooth rim enhancement (arrows).

Diagnosis: Pilocytic astrocytoma

Coarse fibrillarity, elongated oval nuclei and scattered Rosenthal fibres (arrow).