Hydrocephalus is often associated with paediatric posterior fossa tumours. About 75% of patients at the time of presentation have hydrocephalus. Following resection of posterior fossa tumours, 1/3 of the patients have persistent hydrocephalus.
The risk factors of persistent hydrocephalus in patient with posterior fossa tumours include:
- medulloblastomas, ependymomas, brainstem gliomas
- tumours of the IVth ventricles with obstruction of the ventricular outlets
- papilloedema at presentation
- moderate/severe hydrocephalus
- transependymal oedema
- Age < 2 years
The options for pre-op management of hydrocephalus are:
- Conservative management with dexamethasone and close observation
- endoscopic third ventriculostomy
- external ventricular drain
If a patients presents with hydrocephalus with GCS deterioration, the patient would require CSF diversion. There is currently controversy on whether such patient should undergo EVD or ETV.