Cerebral artery stenosis is a lesion in the wall of the cerebral artery with thinning of the lumen due to various causes. The most common cause is atherosclerosis, in which the normal structure of the arterial wall is destroyed and lipid substances are deposited, forming plaques in the arterial wall and narrowing the lumen; sometimes the inner membrane of the arterial wall tears and blood enters the layered structure of the wall, forming arterial entrapment, which is also one of the causes of atherosclerosis leading to vascular stenosis; some young patients can also develop cerebral artery stenosis, and the specific pathogenesis is not well understood and may be related to The specific pathogenesis is not clear, but may be related to inflammatory lesions of blood vessels caused by autoimmune abnormalities.