Hydrocephalus can be clinically classified into various types according to different classifications. According to the pressure, hydrocephalus can be divided into high cranial pressure hydrocephalus and normal pressure hydrocephalus. Normal pressure hydrocephalus is more common in clinical practice and is characterized by enlarged ventricles and normal cerebrospinal fluid pressure, usually due to subarachnoid hemorrhage, meningitis and other diseases. The incidence of normal pressure hydrocephalus According to relevant data, about 750,000 elderly people in the United States have normal pressure hydrocephalus, and there is a study in Sweden that shows that the probability of elderly people over 80 years of age having this disease is 5%, which means that about 1 out of 20 elderly people have normal pressure hydrocephalus, and the prevalence is very high. Since Japan and some European and American countries have researched hydrocephalus a little earlier and paid relatively more attention to it. Experts in China are late in the research of hydrocephalus, and the specific incidence is not yet clear. Normal pressure hydrocephalus clinical symptoms of normal pressure hydrocephalus are mainly manifested in the three major aspects of mental retardation, urinary and bowel disorders and physical disorders. Mental impairment usually appears early, manifested as mild indifference, memory loss, dull expression and slow reaction. Urinary and bowel disorders are usually characterized by urinary urgency and incontinence, most patients appear later, and some patients have loss of bowel control. Physical disorders, initially abnormal gait, such as slow walking, short stride, unstable walking, stride effort, etc.. With the aggravation of the disease, walking difficulties, difficulty in sitting up and down, and in severe cases, inability to stand up, and even difficulty in lying down and turning over. The diagnosis can be made based on medical history, clinical manifestations and imaging examinations. For patients with symptoms and intracranial pressure exceeding the normal range by lumbar puncture, early surgical treatment is recommended.