The following discussion is for general informational purposes only and is not meant to provide the reader with specific medical advice. Please consult with your personal physician, or with a neurologist, for specific advice, guidance and information regarding your particular circumstances.
A stroke occurs when a part of the blood supply to the brain is cut off and brain cells cannot receive oxygen. Eventually, brain cell death occurs. Every year about 550,000 people in the United States suffer from a stroke. About 150,000 people die annually from strokes, making it the third leading cause of death in the U.S. after heart disease and cancer.
There are two main types of stroke: ischemic stroke and hemorrhagic stroke. Ischemic stroke occurs when blood clots or fatty deposits block blood vessels that supply the brain. Blockages may form in or near the brain, or the clots can travel from somewhere else in the body. Hemorrhagic stroke results from ruptured blood vessels inside the brain or on the brain's surface.
There are many contributing factors to stroke. Risk factors that may predispose someone to a stroke include: older age, being male, being black, a previous stroke or transient ischemic attack (a temporary decrease in blood flow to an area of the brain), a positive family history for stroke, diabetics, high blood pressure, heart disease, smoking, obesity, and drug and alcohol use. Causes of stroke include: high blood pressure, atherosclerosis (hardening of the arteries), aneurysm (weakness in the blood vessel wall), or a head injury.
High blood pressure can cause strokes because an increased pressure in the blood vessel wall causes the muscles in the vessel to lose their ability to stretch. This causes the blood vessel walls to thicken, which narrows the vessel passage and reduces blood flow. Fat and cholesterol plaques can collect in the damaged areas of the vessel walls causing a build-up of fatty deposits and thus forming a clot that can block blood flow. This clot can break loose and travel to the brain and cause a blockage of blood supply to the brain.
Symptoms of a stroke vary. Some experience a tingling in the arms or legs, usually on one side of the body. Strokes can cause blurred vision, diminished vision, double vision, or loss of vision. Some people lose their ability to speak clearly. They may have difficulty understanding spoken or written language. They can be confused about day, month, year, who or where they are. A person with a stroke may experience a loss of balance, loss of consciousness, dizziness or a severe headache.
Diagnosing a stroke is done by physical and neurological examination, computed tomography (CT) scans of the brain or magnetic resonance imaging (MRI).
The most common treatment for stroke is antiplatelet agents that "thin" the blood. These are often used to prevent a further stroke event. Thrombolytic agents such as TPA are often used within the first 3 hours of a new stroke and can actually dissolve the clot causing the stroke. It is therefore important to get to the emergency room as quickly as possible if one suspects a stroke so that these treatments can be administered.