Cerebral stroke is divided into two categories: ischemic and hemorrhagic, and ischemic stroke, also known as cerebral infarction, is caused by vascular obstruction, which accounts for 70% to 80% of strokes. Cerebral infarction accounts for 80% of sudden deaths from cerebrovascular disease. The sudden occurrence of cerebral infarction will cause patients to die and become disabled, and most family members feel that this is an unavoidable accident. However, experts believe that most of the patients with cerebral infarction have underlying lesions of cerebral vascular stenosis. If cerebral vascular stenosis can be detected in advance through ultrasound or angiography, and the blood vessels can be unblocked in time, it is possible to prevent sudden cerebral infarction, so what are the precursors of cerebral stroke? Understanding the knowledge about stroke is of great significance in preventing the occurrence of the disease. Studies have found that the precursors of stroke are, in order: (1) Dizziness, especially a sudden feeling of vertigo. (2) Numbness of the limbs, suddenly feel numbness of one side of the face or hands and feet, and in some cases, numbness of the tongue and lips. (3) Temporary slurring of words or inability to speak. (4) Weakness or inactivity of limbs. (5) Headache different from usual. (6) Unexplained sudden fall or fainting. (7) Transient loss of consciousness or sudden changes in personality and intelligence. (8) Significant generalized weakness and limb weakness. (9) Nausea and vomiting or fluctuations in blood pressure. (10) Drowsiness and a state of drowsiness throughout the day. (11) Involuntary twitching of one side or a limb. (12) Sudden sensation in both eyes that you can’t see what appears in front of you for a while. The precursor of stroke is not sudden. About 1/3 of strokes are preceded by a transient ischemic attack, which usually lasts for a few minutes to a few hours, but not more than 24 hours, and is also called a “mini-stroke”. Signs of a “mini-stroke” include: (1) sudden numbness or weakness of one side of the face, arm, or leg; sudden speech or comprehension problems (2) sudden vision problems in one or both eyes; sudden difficulty walking, dizziness, or balance; and (3) sudden onset of an unexplained severe headache. If a patient has a “mini-stroke” and seeks medical attention immediately, the risk of stroke can be effectively reduced. In particular, people with high blood pressure and other key cerebrovascular diseases need to learn to recognize and acknowledge these warning signs of impending stroke, and be taken to the hospital as soon as they are detected. For patients with the above symptoms of stroke, they should first undergo ultrasound examination of the neck, CT scan or MRI, and if these examinations suggest cerebral stenosis, they should further undergo a total cerebral angiogram, which is currently the gold standard for diagnosing cerebral artery stenosis.