Answer to Question 1
There are two types of stroke:
Ischemic stroke results from a blockage that disrupts blood flow to the brain. One of the most common causes is the blockage of a brain artery by a thrombus, or blood clota cerebral thrombosis. Clots generally form around deposits sticking out from the arterial wall. Sometimes a wandering blood clot (embolus), carried in the bloodstream, becomes wedged in one of the cerebral arteries. This is called a cerebral embolism, and it can completely plug up a cerebral artery.
Hemorrhagic stroke occurs when a diseased artery in the brain floods the surrounding tissue with blood. The cells nourished by the artery are deprived of blood and can't function, and the blood from the artery forms a clot that may interfere with brain function. This is most likely to occur if the patient suffers from a combination of hypertension and atherosclerosis. Hemorrhage (bleeding) may also be caused by a head injury or by the bursting of an aneurysm, a blood-filled pouch that balloons out from a weak spot in the wall of an artery.
Answer to Question 2
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