Common complications of hydrocephalus shunts: 1. infection; 2. easy complication of excessive or inadequate shunts, most shunts produce excessive shunts regardless of high or low pressure, excessive shunts can cause epidural hematoma, hypocranial pressure syndrome, and cerebral fissure syndrome. Insufficient cerebrospinal fluid shunt, patient’s visual symptoms do not improve significantly, and examination reveals that ventricular enlargement still exists or changes are not obvious, mainly because of improper shunt valve pressure, resulting in poor cerebrospinal fluid drainage; 3. Another complication of shunt surgery is hemorrhage and intracranial pneumatosis, and the site of hemorrhage is mostly intracerebroventricular, intracerebral or subdural, which should be closely observed and treated according to the situation after these problems occur. 3. ventricular fissure syndrome, in which the ventricles become very small or fissure-like after the placement of a ventricular shunt. In a review of previous analyses, the incidence of ventricular fissure syndrome was 80%, 88% of patients with ventricular fissure syndrome could be completely asymptomatic, and nearly 6.5% of the 12% of patients with fissure syndrome required surgical intervention. Surgical approaches include repair of ventricular end shunt obstruction, replacement of higher pressure shunt valves to increase resistance, addition of anti-siphon valves or replacement of adjustable pressure drains; 4. Hypocranial pressure syndrome, which manifests clinically as headache, nausea, vomiting, bradycardia or drowsiness, and these symptoms are more pronounced when the patient changes position. Patients with hypocranial pressure syndrome will cause excessive shunting when upright, resulting in negative intracranial pressure; 5, isolated four ventricular dilatation, symptoms are mainly headache, dysphagia, low cerebral nerve palsy, ataxia, lethargy and nausea, vomiting, infants and children have long inspiratory breathing, bradycardia, etc., treatment for symptomatic patients can take four ventricular ventral shunt; 6, hydrocephalus shunt after one of the most common complication called obstruction, shunt system obstruction is most common, generally accounting for about 50%-70%, the cause is mainly drainage tube obstruction, abnormal increase in cerebrospinal fluid protein, prevention is to minimize bleeding during surgery; 7, there are other complications, such as shunt fracture, shunt fracture is mainly due to overgrowth of the head, shunt valve dislodgement and other reasons.