Learn about this potentially fatal condition that causes fluid buildup in the brain. It can cause a range of symptoms, from headaches to poor balance.
Update Date: 17.03.2026
Hydrocephalus is the buildup of cerebrospinal fluid (CSF) in spaces called ventricles deep within the brain. This buildup can make the ventricles larger and put pressure on the brain.
Cerebrospinal fluid usually flows through the brain ventricles and around the brain and spinal column. When there's too much fluid, the pressure can harm brain tissue and lead to changes in thinking, movement and other functions.
There are several types of hydrocephalus:
Hydrocephalus can happen at any age, but it occurs more often among infants and among adults 60 and older. Surgery can help drain the extra fluid and control pressure. Therapies can manage symptoms resulting from hydrocephalus.
The symptoms of hydrocephalus can vary by age.
Common symptoms of hydrocephalus in infants include:
Among toddlers and older children, hydrocephalus symptoms might include:
Common hydrocephalus symptoms in young and middle-aged adults include:
Among adults 60 and older, the more common symptoms of hydrocephalus are:
Seek emergency medical care for infants and toddlers with these symptoms:
Seek prompt medical attention for other hydrocephalus symptoms in any age group.
More than one condition can cause the symptoms associated with hydrocephalus. It's important to get a timely diagnosis and appropriate care.
Hydrocephalus happens when there's an issue with how the body makes or absorbs cerebrospinal fluid. Too much fluid builds up because it's either made too quickly or not absorbed fast enough.
Tissues lining the ventricles of the brain produce cerebrospinal fluid (CSF). This fluid flows through the brain's inner spaces and then moves into the areas around the brain and spinal cord. Most of the cerebrospinal fluid is absorbed by blood vessels in the outer layer of the brain.
CSF plays an important role in keeping the brain healthy. It helps by:
Too much cerebrospinal fluid in the ventricles can occur for one of the following reasons:
In many cases, the cause of hydrocephalus isn't clear. But it can result from medical conditions or from issues that affect brain development before birth.
Hydrocephalus that begins before or shortly after birth is called congenital hydrocephalus. In newborns, it may be caused by:
Hydrocephalus also can develop later in life due to health issues or injuries. These may include:
Often, hydrocephalus gets worse over time if it's not treated. Lack of treatment can lead to serious issues, such as learning delays, physical or developmental disabilities, or even death. If hydrocephalus is mild and treated early, many people have few or no long-term complications.
Hydrocephalus can't always be prevented. In many cases, the cause is unknown or happens before birth. But certain steps may lower the risk, especially for conditions that lead to hydrocephalus later in life.
Ask your healthcare professional if you or your child should receive a vaccine against meningitis, once a common cause of hydrocephalus. The Centers for Disease Control and Prevention recommends meningitis vaccination for preteen children and boosters for teenagers.
Vaccination also is recommended for younger children and adults who might be at increased risk of meningitis for any of the following reasons:
A diagnosis of hydrocephalus is usually based on:
The type of neurological exam depends on age. A healthcare professional may ask questions and use simple tests to check muscle strength, movement, balance, and senses such as touch or vision.
Imaging tests can help diagnose hydrocephalus and also may find what's causing symptoms. Common tests include:
There are two main surgical treatments for hydrocephalus.
The most common hydrocephalus treatment is a shunt — a flexible tube with a one-way valve. The valve helps drain extra fluid from the brain at the right speed and in the right direction.
One end of the tube is placed in a ventricle inside the brain. The rest of the tubing is threaded under the skin, usually down to the belly or sometimes to the chest. This allows the fluid to drain and be absorbed by the body.
Most people with hydrocephalus need their shunt for life. Regular checkups are important to make sure it's working well.
Some people may have a surgery called endoscopic third ventriculostomy (EVT) for hydrocephalus. In this procedure, a surgeon uses a small camera to look inside the brain and makes a tiny hole at the bottom of one of the ventricles. This opening lets the extra fluid flow out of the brain, helping to relieve pressure.
Both shunting and ETV surgical procedures for hydrocephalus can result in complications. Shunt systems can stop draining cerebrospinal fluid. Or shunt systems may poorly regulate drainage because of mechanical problems, a blockage or infections. Complications of EVT surgery include bleeding and infections.
Problems after surgery need quick medical care. Sometimes another surgery or other treatment may be needed. Call your healthcare professional right away if you have a fever or any symptoms of hydrocephalus.
Some people with hydrocephalus, particularly children, might need supportive therapies. The need for these therapies depends on the long-term complications of hydrocephalus.
Children's care teams might include:
Children who are in school may need special education. Special education teachers address learning disabilities, determine educational needs and help find needed resources.
Adults with more serious complications might need the services of occupational therapists or social workers. Or they may need to see specialists in dementia care or other medical specialists.
In adults with normal-pressure hydrocephalus that doesn't cause symptoms, treatment may not be needed. Only monitoring may be needed in these instances, as it may take many years to develop any symptoms.
With the help of therapies and educational services, many people with hydrocephalus live with few limitations.
If you have a child with hydrocephalus, there are many resources available to provide emotional and medical support. Children with developmental disabilities might be eligible for government-sponsored healthcare and other support services. Check with your state or county social services agency.
Hospitals and organizations serving people with disabilities are good resources for emotional and practical support. Members of your healthcare team also can help. Ask for help connecting with other families who are living with hydrocephalus.
Adults living with hydrocephalus might find valuable information from organizations dedicated to hydrocephalus education and support, such as the Hydrocephalus Association.
The timing of diagnosing a child with hydrocephalus can depend on the symptoms are and when they appeared. It also may depend on whether there were risk factors for hydrocephalus during pregnancy or delivery. Sometimes hydrocephalus can be diagnosed at birth or before birth.
It's important to take your child to all regularly scheduled well-baby visits. Healthcare professionals monitor your child's development in key areas, including:
Questions you should be prepared to answer during regular checkups might include:
You'll likely start by seeing your child's healthcare professional or your healthcare professional. You may then be referred to a doctor who specializes in brain and nervous system conditions, known as a neurologist.
Be prepared to answer the following questions about your symptoms or your child's symptoms:
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