Atherosclerosis causes plaque to form within the carotid artery walls, usually at the fork where the common carotid artery divides into the internal and external carotid artery. The plaque build-up can narrow or constrict the artery lumen, a condition called<unk> . Rupture of the plaque can release atherosclerotic debris or blood clots into the artery. A piece of this material can break off and travel (embolize) up through the internal carotid artery into the brain, where it blocks circulation, and can cause death of the brain tissue, a condition referred to as ischemic stroke. Sometimes the<unk>  causes temporary symptoms first, known as TIAs, where temporary ischemia occurs in the brain, or retina without causing an infarction. Symptomatic<unk>  has a high risk of stroke within the next 2 days. National Institute for Health and Clinical Excellence (NICE) guidelines recommend that people with moderate to severe (50–99% blockage)<unk> , and symptoms, should have "urgent" endarterectomy within 2 weeks. When the plaque does not cause symptoms, people are still at higher risk of stroke than the general population, but not as high as people with symptomatic<unk> . The incidence of stroke, including fatal stroke, is 1–2% per year. The surgical mortality of endarterectomy ranges from 1–2% to as much as 10%. Two large randomized clinical trials have demonstrated that carotid surgery done with a 30-day stroke and death risk of 3% or less will benefit asymptomatic people with ≥60%<unk>  who are expected to live at least 5 years after surgery. Surgeons are divided over whether asymptomatic people should be treated with medication alone or should have surgery. The common carotid artery is the large vertical artery in red. The blood supply to the carotid artery starts at the arch of the aorta (bottom). The carotid artery divides into the internal carotid artery and the external carotid artery. The internal carotid artery supplies the brain. Plaque often builds up at that division and causes a narrowing<unk> . Pieces of plaque can break off and block the small arteries above in the brain, which causes a stroke. Plaque can also build up at the origin of the carotid artery at the aorta. File:Gray513.Carotid arteries Image:Carotid Plaque.Section of carotid artery with plaque. Blood flows from the common carotid artery(bottom), and divides into the internal carotid artery (left) and external carotid artery (right). The atherosclerotic plaque is the dark mass on the left
Carotid artery stenosis
Carotid artery dissection
Orthostatic hypertension
Cerebral atherosclerosis
Arterial tortuosity syndrome
Cerebral vasospasm
Arteriolosclerosis
Carotid-cavernous fistula