A stroke or cerebrovascular accident (CVA) occurs when the blood supply to a part of the brain is suddenly interrupted by occlusion (an ischemic stroke) or by hemorrhage (a hemorrhagic stroke). The latter occur when a blood vessel in the brain bursts, spilling blood into the spaces surrounding the brain cells or when a cerebral aneurysm ruptures.
The ischemic stroke is usually caused by atherosclerosis (hardening) of blood vessels, embolus (a piece of blood clot originating from atherosclerotic plaque or heart) or small artery disease (the occlusion of small cerebral vessels by the influence of such presumed factors as diabetes mellitus, elevated blood lipid levels, hypertension and cigarette smoking).
The symptoms of stroke are usually easy to spot: sudden numbness or weakness, especially on one side of the body; sudden confusion or trouble speaking or understanding speech; sudden trouble seeing in one or both eyes; sudden trouble walking; dizziness; or loss of balance or coordination. Despite this, it is possible for someone to have a minor stroke and discover it anywhere from hours to years later.
Brain cells die when they no longer receive oxygen and nutrients from the blood or when they are damaged by sudden bleeding into or around the brain. These damaged cells can linger in a compromised state for several hours. With timely treatment, these cells can be saved.
Stroke is diagnosed through several techniques: a short neurological examination, blood tests, CT scans, MRI scans, Doppler ultrasound, and arteriography. Stroke seems to run in some families. Family members may have a genetic tendency for stroke or share a lifestyle that contributes to stroke. The most important risk factors for stroke are hypertension, heart disease, diabetes, and cigarette smoking. Other risks include heavy alcohol consumption, high blood cholesterol levels, illicit drug use, and genetic or congenital conditions. Some risk factors for stroke apply only to women. Primary among these are pregnancy, childbirth, and the menopause and treatment thereof (HRT).
Generally, there are three treatment stages for stroke: prevention, therapy immediately after stroke, and post-stroke rehabilitation. Therapies to prevent stroke are based on treating underlying risk factors. Acute stroke therapies try to stop a stroke while it is happening. Post-stroke rehabilitation is to overcome disabilities that result from stroke damage. Medication or drug therapy is the most common treatment for stroke. Surgery can be used to prevent stroke, to treat acute stroke, or to repair vascular damage or malformations in and around the brain. For most stroke patients, physical therapy is the cornerstone of the rehabilitation process. Another type of therapy involving relearning daily activities is occupational therapy (OT). OT also involves exercise and training to help the stroke patient relearn everyday activities such as eating, drinking and swallowing, dressing, bathing, cooking, reading and writing, and toileting. Speech therapy is appropriate for patients who have no deficits in cognition or thinking, but have problems understanding speech or written words, or problems forming speech.
Although stroke is a disease of the brain, it can affect the entire body. Some of the disabilities that can result from stroke include paralysis, cognitive deficits, speech problems, emotional difficulties, daily living problems, and pain. If the stroke is severe enough, coma or death can result.