Intermittently, there are always inquiries from post-shunt patients or family members who are eager to know if the recent worsening of the patient’s condition suggests a blocked shunt. The following is a brief explanation: Currently, most physicians also use ventriculo-abdominal shunts to treat various types of hydrocephalus, and approximately 100,000 shunts of various types are implanted in patients in developed countries each year. As experience is gained, complications of shunt surgery are becoming more recognized. Shunt blockage is the most common complication, occurring in about 1/3 of patients in the first year after surgery; thereafter, it increases by 5% per year. Eventually, approximately 70% of patients require reoperation to place a new shunt. The clinical presentation of shunt occlusion varies from person to person and is related to the patient’s age, brain tissue elasticity, and the presence of co-infection. Acute shunt occlusion may include: headache, which gradually worsens and changes from intermittent to persistent headache; excessive sleepiness, vomiting, dizziness, photophobia, loss of vision, epilepsy, coma, etc. Chronic shunt blockage may present with: fatigue, mental depression, decreased vision, decreased behavior, premature closure of cranial sutures in infants, etc. A small number of patients may have no obvious symptoms. Once the shunt blockage is suspected, you should actively visit the hospital for CT or MRI examination. Prompt diagnosis and early treatment are required.