Hydrocephalus: What Happens When Fluid Builds Up in the Brain

Your brain is constantly producing and absorbing a clear fluid called cerebrospinal fluid, or CSF. This fluid flows through spaces in the brain called ventricles, cushioning the brain and spinal cord and removing waste. In a healthy brain, CSF production and absorption stay balanced. In hydrocephalus, that balance is disrupted, causing a buildup of fluid, which puts pressure on the brain and affects how it functions.^1,2,3

Why Does It Happen?

Hydrocephalus can affect anyone. It may be present at birth due to genetic factors or complications during fetal development. It can also develop later in life following a brain injury, infection, tumor, or stroke.^1,2

There are two main types: communicating and non-communicating hydrocephalus. In communicating hydrocephalus, fluid can still flow between ventricles but cannot drain properly. In non-communicating hydrocephalus, a physical blockage stops fluid from moving through the ventricles altogether.^1,2

What Are the Symptoms?

Hydrocephalus does not look the same in everyone. Its symptoms are often mistaken for other conditions, and many people live with it for longer than they should before getting answers.

In infants, the most visible sign is a rapidly enlarging head. Other warning signs include:

• High-pitched cry
• Difficulty feeding
• Repetitive vomiting
• Seizures

These require emergency medical attention.^2,3

In older children and adults, symptoms tend to be more gradual. They can include:

• Persistent headaches
• Nausea
• Blurred or double vision
• Difficulty walking
• Balance problems
• Memory or concentration issues^1,2

In adults over 60, a specific pattern is worth knowing about. A shuffling walk, loss of bladder control, and memory loss or confusion often appear together.^1,2 This is known as Normal Pressure Hydrocephalus, or NPH. It closely resembles Parkinson's disease and Alzheimer's disease and is therefore frequently misdiagnosed.^1,2

What Happens Next?

If hydrocephalus is suspected, your doctor will review your medical history and conduct a neurological exam. Imaging such as an MRI or CT scan will be ordered to look for enlarged ventricles or blockages.

The most common treatment is a shunt. This is a small flexible tube placed in the brain. It redirects excess CSF into the abdomen, where the body absorbs it safely. The most widely used system is called a ventriculoperitoneal, or VP shunt.^1,2,3 Shunt surgery is one of the most commonly performed neurosurgical procedures. Most patients experience significant, lasting relief, though regular checkups are important.^1,2

For some patients, a procedure called an endoscopic third ventriculostomy, or ETV, may be an option instead. Here, a small opening is created in the floor of a ventricle, allowing fluid to bypass the blockage and drain naturally.^1,2

If you or a loved one is experiencing any of these symptoms, do not wait. A conversation with a specialist is the most important first step. Dr. Abilash Haridas at the Astra Neurosurgical Institute provides expert evaluation and care for hydrocephalus patients at his practice locations in Los Angeles and Encino.

1. National Institute of Neurological Disorders and Stroke. Hydrocephalus

2. Mayo Clinic. Hydrocephalus

3. Children’s Hospital of Orange County. Hydrocephalus