1.WHO definition
A neurological deficit.
Sudden onset.
With focal rather than global dysfunction.
In which, after adequate investigations, symptoms are presumed to be of non-traumatic vascular origin and last for > 24 hours
2. NINDS 2005 (National Institute of Neurological Disorders and Stroke)
When the blood supply to part of the brain is suddenly interrupted or when a blood vessel in the brain bursts.
3.TIA (Transient Ischemic Attack)
Neurological deficit of vascular origin lasts from few minutes to hours and resolves within 24 hours.
