A stroke secondary to carotid dissection is a loss of brain function due to a stroke caused by a tear in the lining of the carotid artery (a major artery in the neck which supplies blood to the front of the brain).
Causes, incidence, and risk factors
Stroke is caused by a loss of blood circulation to an area or areas of the brain. The specific neurologic deficits may vary depending on the location, extent of the damage, and cause of the disorder. A carotid dissection is when a carotid artery develops a tear in its lining. The flow of blood in between the various layers of the blood vessel causes the layers to separate, resulting in the lumen (channel) narrowing.
Stroke secondary to carotid dissection, unlike many other forms of stroke, may occur in young people, usually under 40 years old. Dissection accounts for less than 5% of strokes.
The risks for stroke secondary to carotid dissection include a history of disorders that cause weakness of the blood vessels, such as Marfan’s syndrome, fibromuscular dysplasia, and others. Risks also include injury or trauma of the neck. Invasive procedures that involve the carotid artery (e.g., arteriogram) can also put someone at risk.
- pain o may occur prior to other neurologic deficits o may be in neck o may radiate into eye
- pulsating noises may be present in the ear (pulsatile tinnitus)
- weakness or total inability to move a body part
- abnormal sensations o numbness, loss of sensation o tingling or other
- Horner’s syndrome o eyelid drooping (ptosis) o abnormal pupil o abnormal facial sweating
- decreased or lost vision, partial or temporary
- language difficulties (Aphasia)
- inability to recognize or identify sensory stimuli (agnosia)
- loss of memory
- vertigo (abnormal sensation of movement)
- loss of coordination
- swallowing difficulties
- personality changes
- mood and emotion changes
- consciousness changes o sleepy o stuporous, somnolent, lethargic o comatose, unconscious
Signs and tests
Findings may include any number of deficits. These can include abnormal vision, movement, sensation, reflexes, and speaking. Occasionally, these findings fluctuate with time, depending on how much blood flow is impaired at the moment they are measured.
An examination should include testing of all neurological functions, including visual, motor, sensory, and cognitive abilities, 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):
- MRI or CT of the head to determine extent and location of stroke
- a Cerebral Angiography reveals changes indicating carotid dissection
- MRA or a Duplex/Doppler ultrasound can also detect dissection
- Blood tests to determine if there are abnormalities in connective tissue or genetic causes of abnormal blood vessels
For a full discussion of treatment, see Stroke.
Antihypertensive medication may be needed to control High blood pressure. Anti-coagulation medication, such as coumadin or aspirin, may be needed for a period of three to six months. Surgical repair of the carotid dissection may be required. If there is a hereditary or underlying disorder of the blood vessels, other therapy may be needed as well.
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.
Calling your health care provider
Stroke due to any cause is a medical emergency and requires immediate treatment. Go to the emergency room or call the local emergency number (such as 911) if symptoms occur.
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 an increased risk of this disorder are present. Safety measures, such as wearing seatbelts in a vehicle and helmets for various activities, may reduce the risk somewhat.
by Sharon M. Smith, M.D.
All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.