Introduction
An arterial dissection is a split or tear of the vessel wall that leads to 2 or more channels of blood flow within the artery. With acute or sudden dissections, the ‘true lumen’ where the blood should be flowing is often compressed by blood flow in the ‘false lumen’. This may affect the blood supply to the organ being supplied by that artery. In relation to the carotid artery, there is a risk of stroke with a sudden dissection.
With chronic or long-term dissections, the blood flow is generally adequate but the artery wall, that has been damaged by the dissection, is weaker and can slowly dilate and form an aneurysm. This can then pose a risk of arterial rupture or compression of adjacent tissues.
Causes
Not all carotid dissections have a definite cause and they may occur spontaneously. They are associated with:
- High blood pressure.
- Trauma.
- Fibro-muscular dysplasia.
- Connective tissue disorders (Ehlers-Danlos, Marfan Syndrome).
- Neck manipulation (massage, chiropractic adjustment).
Symptoms
Carotid artery dissection may not cause any symptoms in some people. More commonly experienced symptoms include:
- Headache.
- Neck pain.
- Stroke symptoms (arm or leg weakness, loss of vision, speech difficulty).
- Eye pain.
- Horner’s Syndrome (droopy eyelid and constricted pupil).
- Pulsation sound in the ear.
- Swallowing difficulties.
Tests
Carotid dissection may be detected on ultrasound, MRI or CT scanning.
It is important to perform imaging of the brain once a carotid dissection has been detected and this is best undertaken with a CT or MRI scan.
Diagnosis
A history of the above symptoms should prompt imaging of the carotid arteries and brain. Imaging is very sensitive to detect a dissection but does not give an indication of when the event occurred.
Treatment
Initial treatment should be performed in hospital to allow appropriate monitoring.
Generally medical treatment is the appropriate initial treatment. Surgery and stenting are rarely performed in the acute / early phase but may be required to treat the complications of chronic dissections. Fortunately, this is seldom required.
Acute carotid dissections require:
- Blood pressure control.
- Pain relief.
- Antiplatelet medications – usually aspirin.
- Anticoagulation.