The carotid arteries run on either side of the neck and are the main blood supply to the brain. Carotid artery stenosis is a narrowing of the lumen of the internal carotid artery as a result of atherosclerotic plaque formation.

A plaque causing significant (i.e. >50%) narrowing of the internal carotid artery lumen leads to turbulent blood flow clot formation on the plaque. Small clots (micro-emboli) can break away from this plaque and lead to the development of transient ischaemic attacks (TIA) or stroke.

Stroke or TIA may take the form of weakness in the arms or legs on the contralateral side to the carotid stenosis. Micro emboli travelling from the carotid to the ophthalmic artery can also result in temporary unilateral blindness (amurosis fugax) on the ipsilateral side to the carotid disease. TIA should be considered a warning sign of an impending major stroke and it should be treated as a medical and surgical emergency.

Risk factors

  • Smoking
  • High blood pressure
  • High blood cholesterol
  • Diabetes