The size of carotid plaque is mainly determined by measuring the thickness of carotid intima, normal carotid intima should be less than 1mm, intima between 1-1.2mm is intimal thickening. When the carotid intima >1.2mm indicates plaque formation, the size of plaque cannot indicate the severity of the disease, but depends on the type of plaque and whether the plaque is in danger of detachment. Soft plaque, flat plaque and mixed plaque are relatively serious plaques. Carotid intima thickening or carotid intima plaque formation is closely related to ischemic stroke or cerebral infarction, generally cerebral infarction is due to plaque shedding or plaque causing large artery stenosis, which causes cerebral thrombosis. Once carotid plaque is formed, it is the same as the risk factors of atherosclerosis, which are affected by age, smoking, alcohol consumption, blood pressure, blood sugar and other factors.