Major Types Of Stroke - What Is A Stroke: Stroke

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Major types of stroke

The two major types of stroke have different causes. Ischemic strokes account for more than 80% of strokes and result from an interruption in blood flow through a specific artery supplying a specific area of the brain. Four basic types of arterial pathologies can cause a blockage that interferes with blood flow (see "Subtypes and causes of strokes"). When brain cells die as a result of ischemic stroke, the resulting injury to the brain is called a cerebral infarction.

Hemorrhagic strokes account for slightly less than 20% of strokes and are caused by rupture of a blood vessel either inside the skull, but outside the brain (known as an extracerebral hemorrhage) or inside the brain (intracerebral hemorrhage). Once a blood vessel ruptures, the resulting heavy bleeding (hemorrhage) tears through the brain. This results in a mass of accumulated blood known as a hematoma, which compresses nearby brain tissue and interferes with its blood supply. The initial arterial rupture has a specific pathological cause that must be determined before treatment can begin (see "Subtypes and causes of strokes").

Whether a stroke is hemorrhagic or ischemic, immediate treatment is crucial in limiting brain damage. Starting treatment within minutes to several hours can often limit the disability caused by the stroke. As doctors often say, "Time is brain."

Last updated:	September 05, 2008