Oxford Carotid Plaque study | NIHR Oxford Biomedical Research Centre

A study of the relationship between clinical characteristics, outcomes and the pathological features of carotid plaques in patients following stroke or transient ischaemic attack (TIA)

The carotid arteries run up the front of the neck, and are crucial to the supply of blood to the brain. Narrowing of the carotid arteries (known as carotid stenosis) is due a build-up of fatty material, called atherosclerotic plaque. If this plaque ruptures, blood clots form and these can cause a stroke, TIA or sometimes a temporary loss of vision in one eye.

This is a carotid plaque removed during endarterectomy. For the procedure, a 7-10cm (2.5-4 inch) cut is made between the corner of the jaw and the breastbone. A small cut is then made along the narrowed section of artery, and the plaque is removed. The artery is then closed with stitches or a patch and the skin is closed with stitches. The operation is often done under local anaesthetic and patients are can usually go home the following day.

Carotid stenosis causes a fifth of all strokes, and in patients who have had a TIA or stroke the diameter of the carotid arteries is commonly assessed, either by ultrasound or during a brain CT or MRI scan. If severely narrowed, a surgical operation called a carotid endarterectomy may be recommended, widening the artery to improve blood flow to the brain and reducing the risk of stroke.

A total of 1,100 carotid plaques were collected for this project, together with information from patients about life style factors and medical history e.g. smoking, high blood pressure, diabetes.

Patients are being followed up over time to see whether they go on to have any other problems caused by atherosclerosis, such as a heart attack or recurrent stroke or TIA.

Half of the plaques have already been processed and examined, resulting in several published papers on features seen in the plaque in relation to smoking, diabetes, age and whether the brain or eye is affected.

The carotid plaques are preserved, sliced into very thin sections, stained and examined under a microscope. They can be assessed for the presence of blood (haemorrhage) and the size of the fatty (lipid) core, along with other important features.

We are now processing the remainder of the plaques and it is hoped that newly available techniques to stain and evaluate the plaques will complement and add to our previous research findings.

Long-term follow-up will also provide information on the long term prognostic value of these observations.

This project is coordinated by the Centre for the Prevention of Stroke and Dementia www.stroke.ox.ac.uk in collaboration with Cellular Pathology, Oxford University Hospitals NHS Foundation Trust.

Stroke and Vascular Dementia