Plaque is the damage to the intima of blood vessels in arteries caused by pathogenic factors such as smoking, hypertension and hyperlipidemia. After the damage, the entry of inflammatory cells and the deposition of lipid substances cause bleeding under the intima, and fibrosis or calcification under the intima of blood vessels may occur with time, and this condition is called plaque. The plaque is the most typical sign of atherosclerosis, and if the plaque gradually increases it may cause narrowing or even occlusion of the blood vessel, and the symptoms of obvious lack of blood supply to the supplied area will appear.