What is a Stroke?

Strokes fall into two categories: Ischemic strokes and Hemorrhagic strokes.

Ischemic Strokes

This is the more common form of stroke and results when a blood clot-often in an artery or its branches-stops blood flow to a part of the brain. Deprived of oxygen, the brain cells are injured or die.

TIAs (Transient Ischemic Attack)

A TIA is a temporary cerebrovascular event, which does not lead to permanent brain damage. A transient ischemic attack (TIA) is a transient stroke that lasts only a few minutes. They are referred to as "mini strokes" and are due to a temporary blockage of a brain vessel. A TIA occurs when the blood supply to part of the brain is briefly interrupted. TIA symptoms, which usually occur suddenly, are similar to those of stroke but do not last as long. Symptoms of a TIA are often short lived and can last from seconds to hours. Symptoms include sudden momentary loss of vision in one or both eyes, weakness or numbness on one side of the body, and language problems such as slurred speech, inability to get words out, or speaking gibberish, and trouble walking, dizziness, loss of balance or coordination.

Because there is no way to tell whether symptoms are from a TIA or an acute stroke, patients should assume that all stroke-like symptoms signal an emergency and should not wait to see if they go away. A prompt evaluation, as soon as symptoms occur, is necessary to identify the cause of the TIA and determine appropriate therapy. Depending on a patient's medical history and the results of a medical examination, the doctor may recommend drug therapy or surgery to reduce the risk of stroke in people who have had a TIA.

TIA's are often warning signs that a person is at risk for a more serious and debilitating stroke. About one-third of those who have TIA's will have acute strokes sometime in the future. Heeding the warning signs of TIA's and treating underlying risk factors can prevent many strokes. The most important treatable factors linked to TIA's and stroke are high blood pressure, cigarette smoking, heart disease, carotid artery disease, diabetes, high cholesterol, and heavy use of alcohol. Medical help is available to reduce and eliminate these factors. Lifestyle changes such as eating a balanced diet, maintaining healthy weight, exercising, and enrolling in smoking and alcohol cessation programs can also reduce these factors.

Hemorrhagic Strokes

This kind of stroke occurs when a blood vessel bursts, causing blood to pool around or inside the brain.

Intracerebral Hemorrhage

Intracerebral Hemorrhage occurs when a blood vessel inside the brain ruptures, leaking blood into the surrounding tissue. Risk factors include: high blood pressure, alcohol and drug abuse, and anticoagulant medication, age (uncommon among people younger than 45), gender (tends to occur more frequently in men), and race (occurs more frequently in African Americans with high blood pressure).

Subarachnoid Hemorrhage

Subarachnoid Hemorrhage occurs when blood spills into the area that surrounds uses but it is usually the result of a rupture aneurysm.