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Definition Return to top
Stroke secondary to carotid stenosis is a group of brain disorders involving loss of brain function due to the obstruction of blood flow to the brain. This is usually related to hardening of the arteries (atherosclerosis).Causes, incidence, and risk factors Return to top
Stroke secondary to carotid stenosis occurs when a major portion of one or both carotid arteries (the arteries in the neck that supply blood to the brain) is narrowed or blocked.
In atherosclerosis (hardening of the arteries), fatty deposits occur in the inner lining of the arteries, and atherosclerotic plaque (a mass of fatty deposits and blood platelets) develops. The plaque itself may obstruct the artery, or a clot (thrombus) may occur at the site of the plaque and cause obstruction. Blockage of the artery usually develops slowly. However, a piece of atherosclerotic plaque (an embolism) may break off and travel to an artery in the brain, causing obstruction far from the site of the plaque.
Atherosclerotic plaque does not always lead to stroke. There are many small blood vessels around the carotid arteries. If blood flow gradually decreases, these small connections will increase in size and by-pass the obstructed area (collateral circulation). If there is enough collateral circulation, even a totally blocked artery may not cause neurologic deficits.
Stroke secondary to carotid stenosis is most common in older people, and often, there is underlying atherosclerotic heart disease or diabetes mellitus.
Risks are the same as for stroke secondary to atherosclerosis. Radiation therapy to the area may also cause carotid stenosis.
Symptoms Return to top
Signs and tests Return to top
Neurologic, motor, and sensory examinations may be done to determine specific neurologic deficits, because they often correspond closely to the location of the injury to the brain. The examination may show emboli in the retina, abnormal reflexes or abnormal extent of "normal" reflexes, muscle weakness, decreased sensation, or other changes. A bruit (an abnormal sound heard with the stethoscope) may be heard over the carotid arteries of the neck.Treatment Return to top
See Stroke.Expectations (prognosis) Return to top
Stroke is the third leading cause of death in developed countries. About one-fourth of the sufferers die as a result of the stroke or its complications, about one-half have long-term disabilities, and about one-fourth recover most or all function.Complications Return to top
See Stroke.Calling your health care provider Return to top
Go to the emergency room or call the local emergency number (such as 911) if symptoms occur.Prevention Return to top
Prevention includes control of risk factors. Hypertension, diabetes, heart disease, and other risk factors should be treated as appropriate. Smoking should be minimized or, preferably, stopped.
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Page last updated: 28 October 2004 |