Hydrocephalus occurs when excess fluid builds up in your brain, most often because of an obstruction preventing proper fluid drainage. The excess fluid can compress surrounding, fragile brain tissue, causing brain damage. Left untreated, hydrocephalus can be fatal. Once known as "water on the brain," hydrocephalus is sometimes present at birth, although it may develop later. About 1 out of 500 children is born with the disorder. The outlook if you have hydrocephalus depends on how quickly the condition is diagnosed and whether any underlying disorders are present.

Complications of Hydrocephalus

The severity of hydrocephalus depends on the age at which the condition develops and the course it follows. If the condition is well advanced at birth, major brain damage and physical disabilities are likely. In less severe cases, with proper treatment, it's possible to have a nearly normal life span and intelligence.

Causes of Hydrocephalus

• Hydrocephalus is caused by excess fluid buildup in your brain.
• Your brain is the consistency of gelatin, and it floats in a bath of cerebrospinal fluid. This fluid also fills large open structures, called ventricles, which lie deep inside your brain. The fluid-filled ventricles help keep the brain buoyant and cushioned.
• Cerebrospinal fluid flows through the ventricles by way of interconnecting channels. The fluid eventually flows into spaces around the brain, where it's absorbed into your bloodstream.
• Keeping the production, flow and absorption of cerebrospinal fluid in balance is important to maintaining normal pressure inside your skull. Hydrocephalus results when the flow of cerebrospinal fluid is disrupted — for example, when a channel between ventricles becomes narrowed — or when your body doesn't properly absorb this fluid.
• Defective absorption of cerebrospinal fluid causes normal pressure hydrocephalus, seen most often in older people. In normal pressure hydrocephalus, excess fluid enlarges the ventricles but does not increase pressure on the brain. Normal pressure hydrocephalus may be the result of injury or illness, but in many cases the cause is unknown.

Signs & Symptoms of Hydrocephalus

The signs and symptoms of hydrocephalus vary by age group and disease progression.

In infants, common signs and symptoms of hydrocephalus include:

• An unusually large head
• A rapid increase in the size of the head
• A bulging "soft spot" on the top of the head
• Vomiting
• Sleepiness
• Irritability
• Seizures
• Eyes fixed downward (sunsetting of the eyes)
• Developmental delay

In older children and adults, common signs and symptoms of hydrocephalus include:

• Headache followed by vomiting
• Nausea
• Blurred or double vision
• Eyes fixed downward (sunsetting of the eyes)
• Problems with balance, coordination or gait
• Sluggishness or lack of energy
• Slowing or regression of development
• Memory loss
• Confusion
• Urinary incontinence
• Irritability
• Changes in personality
• Impaired performance in school or work

Hydrocephalus produces different combinations of these signs and symptoms, depending on its cause, which also varies by age. For example, a condition known as normal pressure hydrocephalus, which mainly affects older people, typically starts with difficulty walking. Urinary incontinence often develops, along with a type of dementia marked by slowness of thinking and information processing.

Diagnosis of Hydrocephalus

In babies and young children, hydrocephalus is likely to be diagnosed:

• During gestation as part of a routine prenatal ultrasound
• During infancy or early childhood, when the head is regularly measured as part of growth monitoring

If your baby's head is visibly enlarged or its growth over time is more rapid than that of other infants, your doctor may recommend an ultrasound of the head. If the results of the ultrasound are abnormal, your infant will need further evaluation.

In older children and adults, a doctor may diagnose hydrocephalus after the child or adult develops signs or symptoms of the condition. To help make the diagnosis, your doctor is likely to perform:

• A careful medical history
• A physical and neurological examination
• Computerized tomography (CT) or magnetic resonance imaging (MRI)

If detailed pictures of the brain from imaging tests reveal hydrocephalus or other abnormalities, referral to a brain surgeon for further evaluation and treatment is likely.

Treatments of Hydrocephalus

Hydrocephalus is usually treated with surgery. Options include:

• Shunt placement. The most common treatment for hydrocephalus is the surgical insertion of a drainage system, called a shunt. It consists of a long flexible tube with a valve that keeps fluid from the brain flowing in the right direction and at the proper rate. One end of the tubing is usually placed in one of the brain's ventricles. The tubing is then tunneled under the skin to another part of the body where the excess cerebrospinal fluid can be more easily absorbed — such as the abdomen or a chamber in the heart.

People who have hydrocephalus usually need a shunt system for the rest of their lives, so additional surgeries may be needed to insert longer tubing to match a child's growth. Revisions to the shunt also may be needed if the tubing becomes blocked or infected.

• Ventriculostomy. This surgical procedure is sometimes used when there's an obstruction of flow between ventricles. In the procedure, your surgeon makes a hole in the bottom of one of the ventricles, to allow the cerebrospinal fluid to flow toward the base of the brain, where normal absorption occurs.

Caring for the whole child

If your child has hydrocephalus, his or her doctor may recommend working with specialists who can help your child thrive in daily life and at school, such as:

• Occupational therapists
• Pediatric psychologists
• Educational experts

These specialists will likely evaluate your child's developmental progress on a regular basis in order to detect any delays in social, intellectual, emotional or physical development. Effective interventions are available to help your child reach his or her full potential.

Prevention of Hydrocephalus

To reduce the risk of hydrocephalus:

• If you're pregnant, get regular prenatal care. Following your doctor's recommended schedule for checkups during pregnancy can reduce your risk of premature labor, which places your baby at risk of hydrocephalus and other complications.
• Protect against infectious illness. Follow the recommended vaccination and screening schedules for your age and sex. Preventing and promptly treating the infections and other illnesses associated with hydrocephalus may reduce your risk.

To prevent head injury:

• Use appropriate safety equipment. For babies and children, use a properly installed, age- and size-appropriate child safety seat on all car trips. Make sure all your baby equipment — crib, stroller, swing, highchair — meets all safety standards and is properly adjusted for your baby's size and development. Older children and adults should wear a helmet while riding a bicycle, skateboard, motorcycle, snowmobile or all-terrain vehicle.
• Always wear a seat belt in a motor vehicle. Small children should be secured in child safety seats or booster seats. Depending on their size, older children may be adequately restrained with seat belts.

Should you be vaccinated against meningitis?

Ask your doctor if you or your child should receive a vaccine against meningitis, once a common cause of hydrocephalus. A meningitis vaccine is now recommended for people ages 2 and older who are at increased risk of this disease due to:

• Traveling to countries where meningitis is common
• Having an immune system disorder called terminal complement deficiency
• Having a damaged spleen or having had your spleen removed
• Living in a dormitory as a college freshman
• Joining the military

When to seek Medical Advice

Infants and toddlers require emergency medical care for these signs and symptoms:

• A high-pitched cry
• Problems with sucking or feeding
• Unexplained, recurrent vomiting
• Exhibiting an unwillingness to bend or move the neck or head
• Breathing difficulties
• Seizures

The following signs and symptoms don't constitute an emergency, but they do warrant a call to your child's doctor:

• A rapid increase in the size of the head
• A bulging "soft spot" on the top of the head
• A change in the appearance of the face or eyes
• A decreased level of interest or engagement in social interactions

Older adults need a complete physical and neurological exam if experiencing:

• Walking difficulties
• Impaired thinking
• Urinary incontinence