Hydrocephalus is a relatively common condition in neurosurgery. It is usually caused by intracranial lesions and some cranial trauma, resulting in excessive secretion of cerebrospinal fluid, obstruction of circulatory pathways or impaired absorption, which leads to enlargement of the ventricles. The types of hydrocephalus are complex and diverse. Generally, it can be divided into high cranial pressure hydrocephalus and normal cranial pressure hydrocephalus according to pressure, and normal cranial pressure hydrocephalus is also called normal pressure hydrocephalus. 1.What is normal pressure hydrocephalus? Normal pressure hydrocephalus is a kind of traffic hydrocephalus syndrome in which the cerebrospinal fluid pressure is normal although the ventricles are enlarged, and the intracranial pressure usually does not exceed 23.9~26.6kPa (180~200mmHg). This disease occurs in elderly people over 65 years old, mostly due to chronic cerebrospinal fluid absorption and circulation dysfunction, with brain tissue volume reduction and brain cell destruction as the main manifestations. When the condition is severe, it brings many inconveniences to patients’ normal life and seriously affects the quality of life. 2.What are the clinical manifestations of normal pressure hydrocephalus? In the initial stage, most patients show language impairment and reduced calculation ability, for example, when someone communicates with others, he or she does not speak clearly, and when he or she goes out to buy something, he or she forgets the way back; as the disease slowly develops, the patient then becomes unstable in walking, his or her stride becomes smaller and slower; at this time, if he or she is not actively treated, he or she may become incontinent or even bedridden. These symptoms are collectively known as the “triad of symptoms”. 3. Diagnostic criteria for normal pressure hydrocephalus In addition to the above symptoms, the diagnosis of normal pressure hydrocephalus needs to be confirmed by further examination with imaging. The diagnostic criteria for hydrocephalus is through imaging, cranial CT examination is needed, if the CT finds that there is progressive enlargement of the ventricles, it can be diagnosed as hydrocephalus. After the diagnosis, the patient does not need to be overly anxious, and can recover by actively cooperating with the doctor’s treatment. At present, experts have summed up a set of advanced characteristic diagnosis and treatment techniques, and have made outstanding achievements in hydrocephalus diagnosis and treatment, and many patients with critical conditions have gradually recovered.