Loss of brain function due to stroke caused by bleeding within the lining of the carotid artery of the neck.

Causes, incidence, and risk factors

Stroke secondary to carotid dissection, unlike many other forms of stroke , may occur in young people, usually under 40 years old. Stroke involves loss of brain functions (neurologic deficits) caused by a loss of blood circulation to areas of the brain. The specific neurologic deficits may vary depending on the location, extent of the damage, and cause of the disorder. Stroke is caused by reduced blood flow (ischemia) that results in deficient blood supply and death of tissues in that area (infarction). The carotid arteries are two arteries in the neck that supply blood to the anterior part of the brain. "Carotid dissection" means that there is an injury to the artery or a weakened area in the lining of the artery. Blood leaks into the lining of the artery, possibly causing a clot in the wall of the artery and therefore reducing blood flow to the brain. Risks for stroke secondary to carotid dissection include a history of Marfan's syndrome , fibromuscular dysplasia, or other disorders that may involve weakness of the blood vessels. Risks also include a history of injury or trauma involving the neck. Rarely, cases of carotid dissection have occurred as a result of massage of the neck.

Signs and tests

Maximum neurologic deficits may be present at the beginning (onset) of the stroke , or symptoms may progress or fluctuate for the first day or two (stroke in evolution). Once there is no further deterioration, the stroke is considered a complete stroke. An examination may include neurologic, motor, and sensory testing to determine the specific deficits present. The examination may show changes in vision or visual fields , changes in reflexes including abnormal reflexes or abnormal extent of "normal" reflexes, abnormal eye movements, muscle weakness , decreased sensation , and other changes. A bruit, an abnormal sound heard with the stethoscope, may be heard over the carotid arteries of the neck. The blood pressure may be high. Horner's syndrome may occur, which involves a small pupil, drooping of one eyelid , lack of sweating on one side of the forehead, and a sunken appearance to one eye. Tests (see also tests for stroke):

Treatment

See Stroke . Additional treatment: Antihypertensive medication may be needed to control high blood pressure . Anti-coagulation with coumadin or aspirin may be indicated for a period of 3-6 months. Surgical repair of the carotid dissection may be indicated.

Expectations (prognosis)

The outcome for stroke secondary to carotid dissection may be better than for stroke from many other causes, especially if the dissection is discovered and treated promptly.

Complications

See Stroke .

Calling your health care provider

Go to the emergency room or call the local emergency number (such as 911) if symptoms occur. Note: Stroke requires immediate treatment.

Prevention

Stroke secondary to carotid dissection may not be preventable in some instances. Care should be taken to protect the neck from injury, especially if diseases associated with increased risk of this disorder are present.