What is carotid dissection?

A carotid dissection is a tear in one of your carotid arteries. These are a set of paired arteries at the sides of your neck. These arteries supply blood to your brain.

The first portion of each carotid artery is the called the common carotid artery. Each common carotid artery has an internal and an external branch. The external branch carries blood to your face and scalp. The internal branch carries blood to the front part of your brain.

A dissection is a tear of the inner layer of the wall of an artery. The tear lets blood get in between the layers of the wall and separate them. This causes the artery wall to bulge, and the bulge can slow or stop blood flow through the artery. It can also cause problems by pressing on nearby structures, such as nerves. 

The tear can also trigger the body's clotting system. A clot can then block blood flow at the site of the tear. Or pieces of the clot can break off and block blood flow in smaller branches of the artery. Blocked or decreased blood flow can lead to a transient ischemic attack (TIA) or stroke. 

A carotid dissection can occur at any age. It tends to occur more often in younger adults than in older adults. It is a common cause of stroke in people under age 50. It is slightly more common in men than in women.

What causes carotid dissection?

An injury to the neck can cause carotid dissection. The injury may be caused by something like a car accident.

Some people with diseases that are known to weaken arterial walls are at greater risk for a dissection. These dissections can occur with vigorous physical activity such as:

• Swimming and scuba diving
• Skating and dancing
• Play sports such as tennis, basketball, or volleyball
• Doing yoga
• Riding roller coasters or other rides
• Jumping on a trampoline
• Giving birth
• Having sex
• Sneezing or coughing
• Receiving chiropractic manipulations

 A carotid dissection can also occur suddenly, without a known cause.

What are the risks for carotid dissection?

Researchers have found some factors that increase the risk of having a carotid dissection. But some people who get carotid dissections do not have any of those risk factors.

In some cases, genes may play a part. Having certain combinations of genes may increase your risk. If you have family members who have had artery dissections, you may have an increased risk. Other conditions that may increase your risk include:

• Infection
• High blood pressure
• Migraine headaches
• Smoking
• An elongated styloid process
• Use of birth control pills
• Alcohol use
• Fibromuscular dysplasia
• Ehlers-Danlos syndrome
• Marfan syndrome
• Homocystinuria
• Alpha-1 antitrypsin deficiency
• Osteogenesis imperfecta
• Cystic medial necrosis of the aorta
• Segmental mediolytic arteriopathy
• Reticular fiber deficiency
• Reversible cerebral vasoconstriction syndrome
• Autosomal dominant polycystic kidney disease

What are the symptoms of carotid dissection?

Some people who have carotid dissection do not have any symptoms. In other cases, symptoms may occur suddenly or may develop over several days. Common symptoms include:

• Headache
• Scalp pain
• Eye pain
• Neck pain
• One eye with a droopy lid and small pupil (partial Horner syndrome)
• One-sided weakness or numbness
• Pulsing sound in an ear
• Trouble swallowing
• Abnormal or lost sense of taste

How is carotid dissection diagnosed?

Your healthcare provider will ask about your symptoms and past medical conditions. He or she may also ask about recent injuries and activities. During a physical exam, your doctor may focus on your face and eyes, strength, reflexes, and sensation.

Tests are done to evaluate for different types of headaches, nerve disorders, bleeding of the brain, and stroke due to other causes. Imaging of the carotid arteries and evaluation of blood flow can help diagnose a dissection. Some tests that may be done include:

• Lumbar puncture with analysis of your cerebrospinal fluid
• Magnetic resonance imaging (MRI) of the brain and neck
• Magnetic resonance angiography (MRA) of the brain and neck
• Cranial computed tomography (CT)
• Cranial computed tomography angiography (CTA)
• Carotid doppler and ultrasound

If you may have a specific condition that increases your risk of carotid dissection, you may need additional tests. Your doctor may refer you to a neurologist, vascular surgeon, or neurosurgeon to make the diagnosis and to manage your carotid dissection.

How is carotid dissection treated?

In many cases, people need to go into the hospital for monitoring and initial treatment. Treatment options depend on your age, medical conditions, and symptoms, and may include:

• Clot-busters (thrombolytics), if your dissection caused a stroke
• Heparin to prevent more blood clots
• Intravenous (IV) fluids
• Blood pressure medicine
• Insulin or glucose to control your blood sugars
• Pain medicines, such as acetaminophen, ibuprofen, or naproxen
• Antiplatelet medicines, such as aspirin
• Anticoagulant therapy with warfarin or other anticoagulation drugs

You may need to take antiplatelet or anticoagulant medicines for 3 to 6 months. At that point, you may need imaging studies to see how your carotid artery is healing.

If you have problems with repeated carotid dissection, your doctor may advise getting a stent or having surgery to repair or bypass your carotid artery.

What are the complications of carotid dissection?

A carotid dissection can cause problems with blood flow to your brain or eyes. This can cause a TIA, stroke, or one-sided blindness. Any of these are medical emergencies. Call 911 if you think you might be having a stroke or TIA or if you have sudden loss of vision.

When should I call my healthcare provider?

If your symptoms get worse or you have new symptoms, let your healthcare provider know.

Key points about carotid dissection

• A carotid dissection is a tear in the inner layer of the wall of a carotid artery that allows bleeding into the artery wall.
• A carotid dissection can be due to injury. Or it may occur suddenly with no known cause.
• Medical imaging tests can help rule out other conditions with similar symptoms.
• Long-term treatment of carotid dissection involves taking antiplatelet or anticoagulant medications.
• If you have multiple carotid dissections, you may need a stent or surgery.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

• Know the reason for your visit and what you want to happen.
• Before your visit, write down questions you want answered.
• Bring someone with you to help you ask questions and remember what your provider tells you.
• At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
• Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
• Ask if your condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if you do not take the medicine or have the test or procedure.
• If you have a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your provider if you have questions.