- Vasospasm is narrowing of cerebral vessels following subarachnoid haemorrhage (SAH), visible angiographically or via transcranial doppler
- It occurs in 60-70% of patients with SAH
- Typically starts at day 3 to 4 days after aneurysm rupture, peaking at day 7 to 10 days, and resolves by 14 to 21 days
- It is more common in smokers and patients with high-grade SAH
