Background/Epidemiology
- Incidence ~3/100,000
- More common in obese, young women
- Occurs in the absence of any identifiable underlying cause e.g. structural lesion, hydrocephalus
- Cause not fully understood- ?problem with CSF reabsorption by arachnoid villi
Presentation
- Headache
- Diplopia or visual disturbance (most commonly ‘greying out’)
- Often change with posture e.g. bending/straining
- Papilloedema and 6th nerve palsy may be present
Investigations
- Imaging to rule out other causes
- Ventricles are usually normal
- LP can reveal increased CSF pressure; alternatively ICP monitoring
Management
- Management can be difficult.
- Weight loss can be tried
- Azetazolaminde/topiramate
- Repeated LP
- Surgery (optic nerve sheath fenestration or shunting)