What is carotid stenosis?
The carotid arteries are the two main blood vessels that run up either side of the neck and supply blood to the brain. Carotid stenosis is a narrowing of one of these arteries, most often caused by atherosclerosis, a build-up of fatty deposits known as plaque within the artery wall.
As the plaque enlarges, it narrows the channel through which blood flows. Small fragments or blood clots can also break away from the plaque and travel to the brain, where they may block a smaller vessel. This is one of the mechanisms by which carotid disease leads to a stroke or a transient ischaemic attack.
Symptoms and stroke risk
Carotid stenosis often causes no symptoms at all and may be found incidentally during a scan performed for another reason. When symptoms do occur, they are usually the result of reduced blood flow or a small clot reaching the brain or eye, and may include:
- Sudden weakness or numbness of the face, arm or leg, usually on one side of the body
- Sudden difficulty speaking or understanding speech
- Temporary loss of vision in one eye, sometimes described as a curtain coming down
- Sudden loss of balance or coordination
Stenosis that has already caused such symptoms is described as symptomatic and generally carries a higher risk of further stroke than stenosis found before any symptoms occur. The degree of narrowing, the appearance of the plaque and a person's other health factors all influence that risk and are weighed when considering treatment.
If you or someone near you develops sudden weakness, numbness, difficulty speaking, or loss of vision, call 000 immediately. Stroke is a medical emergency and treatment is most effective when given quickly.
How it is diagnosed
Carotid stenosis is assessed using imaging that shows both the degree of narrowing and the nature of the plaque. The investigations commonly used include:
- Carotid ultrasound, a quick and painless scan that measures blood flow in the neck arteries
- CT angiography or MR angiography, which provide detailed images of the arteries from the chest to the brain
- Catheter angiography, a precise X-ray study of the arteries used in selected cases and at the time of treatment
Dr Mitchelle reviews this imaging in detail to determine the severity of the narrowing and whether treatment is likely to reduce the risk of future stroke.
Treatment options
Treatment is tailored to each person, based on whether the stenosis has caused symptoms, the degree of narrowing, and individual health factors. The main approaches are outlined below.
Medical management
For many people, particularly those without symptoms or with milder narrowing, the most appropriate treatment is careful management of the underlying risk factors. This typically involves medications to lower cholesterol and control blood pressure, antiplatelet medication, and support with lifestyle factors such as stopping smoking. This is an active treatment in its own right and forms the foundation of care for all patients with carotid disease.
Carotid artery stenting
Carotid stenting is a minimally invasive, endovascular treatment. Working through a small puncture in an artery, a fine catheter is guided to the narrowed segment, where a small mesh tube called a stent is placed to hold the artery open and stabilise the plaque. Because it is performed from within the artery, stenting does not require an incision in the neck, and it may be considered in people for whom surgery is higher risk.
In late 2025, the landmark CREST-2 trial reported that in patients with severe (70% or greater) narrowing that has not caused symptoms, adding stenting to intensive medical therapy significantly reduced the risk of stroke compared with medical therapy alone. You can read a plain-language summary of the trial and who it applies to here.
Carotid endarterectomy
Endarterectomy is a surgical procedure, performed by a vascular surgeon, in which the plaque is removed directly through an incision in the neck. It is a well-established and effective treatment, and for some patients it remains the preferred option. Where appropriate, Dr Mitchelle works alongside surgical colleagues so that each person is offered the approach best suited to their circumstances.
Carotid disease is managed across several specialties. Where surgery is the preferred option, care proceeds with vascular surgical colleagues, and the recommended pathway reflects your overall health and the current evidence.
Arranging an appointment
A referral from your GP or treating specialist is required to arrange a consultation. If you have been told you have carotid narrowing, please bring or forward any relevant imaging so that it can be reviewed at your appointment.