Cerebral ischemia includes two types: transient ischemic attack and cerebral infarction, both of which have common manifestations and characteristic changes. The common manifestation is functional impairment, which can have prodromal symptoms such as limb numbness and weakness, and focal signs mostly peak more than 10 hours or 1-2 days after the onset, depending on the size and location of the ischemic focus. Consciousness is generally clear, and when basilar artery thrombosis or large cerebral infarction occurs, impaired consciousness or even life-threatening may occur. Transient ischemic attack, with sudden onset, can rapidly appear limited neurological or retinal dysfunction, such as episodic unilateral limb weakness or mild hemiparesis, aphasia, etc., mostly peaking in about 5 minutes, with short duration and rapid recovery, leaving no sequelae. Symptoms mostly disappear completely within 24 hours, but can recur thereafter. Cerebral infarction generally has more severe and complete symptoms of neurological deficits, including aphasia, hemiparesis, hemianesthesia, vertigo, etc. Complete cerebral infarction may peak within 6 hours, and slowly progressive cerebral infarction may gradually worsen within 1-2 weeks after onset. The condition is usually severe and may be accompanied by seizures or even coma. Cerebral infarction can occur in both middle-aged and elderly people, and can also be seen in young people, and the incidence of young people has been on the rise in recent years. If cerebral ischemia lasts for a long time, it can cause changes such as brain tissue necrosis, resulting in irreversible damage. Prompt medical attention should be sought.