Stroke is the most common form of stroke in winter. Stroke, commonly known as “stroke”, is a sudden blockage or rupture of a cerebral blood vessel that causes severe brain dysfunction, ranging from hemiplegia and abnormal sensation to impaired consciousness and life-threatening injury. The most common clinical stroke is ischemic stroke, also known as cerebral infarction, which accounts for more than 80% of all stroke cases. According to statistics, there are about 1.5-2 million new cases of ischemic stroke in China every year, and nearly 40% of these patients are left with severe disability, and 80% of them recur within 2-5 years. With the improvement of living standards and lifestyle changes in China, the incidence of stroke is on the rise. Stroke seriously endangers the health of middle-aged and elderly people and brings a heavy economic burden to both families and society. It is now recognized that carotid artery stenosis and occlusion caused by carotid atherosclerosis plaque or atherosclerotic plaque dislodgement and embolization are the main causes of ischemic stroke. Clinical studies have found that 30-50% of strokes are associated with atherosclerotic lesions at the bifurcation of the common carotid artery. The more severe the stenosis of the carotid artery caused by atherosclerotic plaque, the higher the risk of stroke for patients with less than 70% stenosis is 2.1% per year, while the risk of stroke for patients with more than 70% stenosis can be as high as 10% per year. Although there are no clinical symptoms in the early stage of carotid atherosclerosis plaque formation, which is called “subclinical” or “subhealth” stage, the “root of the problem” of stroke is already laid at this time. As the sclerotic plaque enlarges and causes the artery to narrow by more than 70% or when small emboli are dislodged from the carotid artery, fainting, transient blackness, limb numbness, weakness or even paralysis may occur. These symptoms can last from a few minutes to a few hours, and usually do not exceed 24 hours. The medical term for this is transient ischemic attack (TIA for short). About 1/3 of all ischemic strokes are preceded by a TIA episode. Without active intervention at this stage, a severe cerebral infarction will arrive unannounced in a short period of time. Screening by carotid ultrasound and MRA (magnetic resonance angiography) on the aortic arch is recommended in people over 50 years old with a history of smoking and high risk of cerebral ischemia with hypertension, hyperlipidemia and hyperglycemia as an important measure to reduce the incidence of stroke. Cerebral angiography can also be done if necessary. If the screening is positive and the carotid stenosis is more than 70% and the surface of the sclerotic plaque is uneven and uneven in texture, or there are ulcers or bleeding within the plaque, surgical intervention using carotid endarterectomy is a good choice for such patients, in addition to controlling risk factors and drug treatment. Removal of the carotid intima of atherosclerotic lesions eliminates the source of emboli causing cerebrovascular blockage while increasing cerebrovascular blood flow, and is the standard procedure for treating carotid stenosis to prevent cerebral infarction. It has been clinically proven in foreign countries for more than half a century and is a mature treatment method. Every year, hundreds of thousands of patients in Europe and the United States reduce the risk of stroke by undergoing carotid endarterectomy. The Department of Neurosurgery at Ruijin Hospital has also performed carotid endarterectomy in recent years with satisfactory results. In order to prevent the occurrence of cerebral infarction, we need to pay attention to the subhealth of carotid artery! Timely examination and detection of abnormalities and timely surgical treatment can turn the danger into success.