Blood in subarachnoid space (between arachnoid and pia mater)
Expansion
Subarachnoid Haemorrhage
Purpose
Medical emergency; computed tomography shows hyperdensity in sulci; lumbar puncture confirms if computed tomography negative
Clinical Context
Subarachnoid haemorrhage: aneurysm rupture most common (80 percent). Non-contrast computed tomography shows blood in sulci or basal cisterns. Angiography finds source. Risk of vasospasm, hydrocephalus, rebleeding.
Related Terms
- Intracranial bleeding
- Stroke
Key Points
- Subarachnoid haemorrhage from ruptured aneurysm most common cause; risk of rebleeding, vasospasm, hydrocephalus