A stroke is a sudden loss of brain function. It is caused by the interruption of flow of blood to the brain (ischemic stroke) or the rupture of blood vessels in the brain (hemorrhagic stroke). The interruption of blood flow or the rupture of blood vessels causes brain cells (neurons) in the affected area to die. The effects of a stroke depend on where the brain was injured, as well as how much damage occurred. A stroke can impact any number of areas including your ability to move, see, remember, speak, reason and read and write.

Essentials for Diagnosis 
(1) Chief manifestations are trance even coma or mental confusion, hemiplegia, distortion of the mouth and tongue, stiff tongue and dysphasia, numbness in one side of the body.
(2) Abrupt onset.
(3) The disease is often caused by some precipitating factors and such aural symptoms as dizziness, headache, numbness of limbs and weakness are commonly seen.
(4) It is mostly seen in people aged 40 and older.
(5) Cerebrospinal fluid examination, brain CT scanning and MRI are helpful in making a diagnosis.