In western industrialized countries such as the United States, stroke is the third leading cause of death, after heart disease and cancer, and the leading cause of disability. Stroke is currently the top three causes of death in China and the first cause of physical disability in people over 60 years of age. With the improvement of our living standard and the development of the aging trend of the population, the incidence of stroke in China is now showing a “blowout”, with the prevalence of symptomatic stroke in China reaching 1.82% in 2012, and rising at a rate of about 9% per year. The first is cerebrovascular infarction, which accounts for the highest percentage of stroke patients, about 88%; the second is cerebral parenchymal hemorrhage (commonly known as “cerebral hemorrhage”), which accounts for about 9% of stroke patients; and the third is subarachnoid hemorrhage, which accounts for about 3% of stroke patients. In the United States, the incidence of asymptomatic cerebral infarction in the general population over 55 years of age is about 11%; there are no statistics on this in China, but the incidence of asymptomatic cerebral infarction in urban populations with a high standard of living should be similar to that in Western countries. And carotid artery stenosis due to carotid atherosclerosis is one of the main causes of cerebral infarction. Among the causes of cerebral infarction, those caused by carotid stenosis account for about 10-18%. The chance of stroke caused by carotid stenosis increases with the degree of stenosis, when the carotid stenosis is 70%-79%, about 19% of people will have a stroke within two years; when the carotid stenosis is 80%-89%, about 28% of people will have a stroke within two years; when the carotid stenosis is 90% or more, about 33% of people will have a stroke within two years. According to statistics, about 9% of people over 60 years of age in China suffer from carotid artery stenosis, mostly in the bifurcation of the common carotid artery and the beginning of the internal carotid artery. Some stenotic lesions may even progress to complete occlusive lesions. The main cause of carotid stenosis is atherosclerosis due to hypertension, diabetes, and dyslipidemia. Surgical repair of narrowed carotid arteries can effectively reduce the incidence of stroke and the disability caused by stroke. Every year, hundreds of thousands of people in the United States undergo various types of stenosis carotid artery repair surgery, effectively reducing the incidence of stroke. The 2011 U.S. Guidelines for the Management of Extracranial Carotid and Vertebral Arteries recommend screening for asymptomatic carotid artery stenosis in the following high-risk groups. Carotid ultrasound is the most cost-effective screening modality. (1) carotid murmur on auscultation; (2) symptomatic peripheral vascular disease, coronary atherosclerotic disease and atherosclerotic aortic aneurysm; (3) greater than 2 of the following risk factors: hypertension, hyperlipidemia, smoking, first-degree relative with a history of atherosclerosis before age 60, and family history of ischemic stroke. Early symptoms of carotid artery stenosis Most patients with carotid artery stenosis have no symptoms in the early stages, or the symptoms are not obvious and can easily be overlooked. Because carotid stenosis causes insufficient blood supply to the brain, patients mainly show drowsiness, memory loss, and inability to concentrate at work in the early stage. Transient ischemic attack (TIA, commonly known as “mini-stroke”) is a typical symptom caused by carotid artery stenosis. Transient ischemic attack refers to sudden transient and reversible neurological dysfunction caused by a temporary blockage of blood supply to a specific part of the brain. The onset typically lasts for several minutes, usually recovers completely within 30 minutes, and can be recurrent. Traditionally defined as complete disappearance of symptoms within 24 hours, the new definition is now that symptoms disappear within 1 hour. The onset is usually longer than two hours with residual neurological deficit manifestations and imaging signs visible on CT or MRI. It is mainly triggered by sudden cerebral vasospasm or dislodgement of tiny emboli in the vessel wall. The onset is usually rapid and can peak in 5 minutes with symptoms of neurological deficits and black clouding. Symptoms of neurological deficit include visual field deficit, vertigo, transient aphasia, motor dysfunction, and sudden transient weakness of one limb. TIA is usually a prelude to stroke, and the risk of stroke is highest within a week after the onset of symptoms. Prevention of carotid artery stenosis The best way to treat a disease is to keep this disease from occurring. Atherosclerotic stenosis of the carotid arteries is only a manifestation of systemic atherosclerotic disease in the neck. When you are found to have atherosclerotic plaque in the arteries in your body during a health checkup or have hypertension, hyperlipidemia, or smoking, you should actively begin treatment. For example, quit smoking, increase exercise appropriately, and change poor dietary habits. When these methods have limited effect, appropriate medication should be given to slow down the development of sclerotic plaque. Treatment of carotid artery stenosis (1) Treatment of mild to moderate carotid artery stenosis Asymptomatic carotid artery stenosis with a stenosis of less than 50% does not require surgical treatment, and it is sufficient to control the development of stenosis with drugs and other treatments. (2) Selection of surgical treatment methods There are two main surgical methods for the treatment of carotid stenosis: one is carotid endarterectomy; the other is carotid stenting. There is no significant difference between the two methods in terms of long-term efficacy, and the main difference lies in the perioperative risk. Compared to carotid endarterectomy, carotid stenting is associated with a higher rate of perioperative stroke and a lower risk of surgical site hematoma and wound infection. Another disadvantage of carotid endarterectomy is that it has a surgical wound that is aesthetically displeasing, but it is less expensive in our country. Another advantage of carotid artery stenting is that it is less invasive and more suitable for patients of advanced age and poor physical condition who cannot tolerate conventional surgery. Carotid endarterectomy has a history of hundreds of years and has proven efficacy, while stenting has a shorter history and the material of the stent has a greater impact on long-term prognosis. The choice of the procedure should be based on the patient’s physical condition, economic conditions and other comprehensive considerations. In foreign medical guidelines, for patients with carotid stenosis greater than 70% and no history of stroke, carotid endarterectomy is recommended over stenting. Currently, more than 200,000 patients in the United States undergo carotid endarterectomy each year, and the number of patients undergoing carotid stenting is slightly less than that of carotid endarterectomy. Approximately 60% of carotid stenosis patients in the United States are treated surgically in vascular surgery, and approximately 40% are treated in neurosurgery. For patients with surgical indications, low surgical risk, and relatively young age, I recommend carotid endarterectomy at this stage; after all, this procedure has been tested for hundreds of years and has definite long-term efficacy. With the advancement of material technology, carotid artery stenting may be superior to carotid endarterectomy in the future.