The normal physiological function of the human brain depends on an adequate blood supply, and although the weight of the human brain accounts for only 3% of body weight, the blood supply accounts for about 20% of the cardiac blood output. However, the blood vessels supplying the brain are often narrowed due to atherosclerosis, arterial entrapment, hypertension, diabetes, etc., resulting in inadequate blood supply to the brain. Stenosis of blood supplying arteries in the brain includes both intracranial and extracranial stenosis, which is the main cause of insufficient local cerebral blood perfusion, cerebral thrombosis or embolism dislodgement, thus producing corresponding symptoms of cerebral ischemia such as transient ischemic attack (TIA), dizziness, limb weakness and numbness, unstable walking, slurred speech, blurred vision, and even severe stroke. The death and disability rate of stroke is extremely high and the rescue effect is poor, but on the contrary, if the narrowing of the cerebral blood supply artery is detected in time and treated with standardized drugs or surgery, it is often possible to prevent stroke as well as recurrent ischemic events, improve one’s quality of life, and avoid burdening one’s family and society. Therefore, patients with symptoms of ischemic attack, elderly people, and high-risk patients with atherosclerosis, hypertension, hyperlipidemia, and diabetes mellitus should undergo magnetic resonance angiography, CT angiography, and cerebral angiography and other related examinations as early as possible to clarify the presence of arterial stenosis and take corresponding standardized treatment to improve blood supply to brain tissues and prevent strokes. If a stroke has occurred, the vascular condition should be clarified and treated promptly after recovery to prevent another stroke.