Hydrocephalus is a buildup of fluid inside the skull that leads to brain swelling.
Hydrocephalus means “water on the brain.”
Causes, incidence, and risk factors
Hydrocephalus is due to a problem with the flow of the fluid that surrounds the brain. This fluid is called the cerebrospinal fluid, of CSF. It surrounds the brain and spinal cord, and helps cushion the brain.
CSF normally moves through the brain and the spinal cord, and is soaked into the bloodstream.
CSF levels in the brain can rise if:
- The flow of CSF is blocked
- It does not get absorbed into the blood properly
- Your brain makes too much of it
Too much CSF puts pressure on the brain. This pushes the brain up against the skull and damages brain tissue.
Hydrocephalus may begin while the baby is growing in the womb. It is common in babies who gave a myelomeningocele, a birth defect in which spinal column does not close properly.
Hydrocephalus may also be due to:
- Genetic defects
- Certain infections during pregnancy
In young children, hydrocephalus may result from the following conditions:
Infections that affect the central nervous system (such as meningitis or encephalitis), especially in infants
Bleeding in the brain during or soon after delivery (especially in premature babies)
Injury before, during, or after childbirth, including subarachnoid hemorrhage
Tumours of the central nervous system, including the brain or spinal cord
Injury or trauma
Hydrocephalus most often occurs in children, but may also occur in adults and the elderly.
Symptoms
Symptoms of hydrocephalus depend on:
- Age
- Amount of brain damage
What is causing the buildup of CSF fluid?
In infants with hydrocephalus, it causes the fontanel (soft spot) to bulge and the head to be larger than expected.
Early symptoms may also include:
- Eyes that appear to gaze downward
- Irritability
- Seizures
- Separated sutures
- Sleepiness
- Vomiting
Symptoms that may occur in older children can include:
- Brief, shrill, high-pitched cry
- Changes in personality, memory, or the ability to reason or think
- Changes in facial appearance and eye spacing
- Crossed eyes or uncontrolled eye movements
- Difficulty feeding
- Excessive sleepiness
- Headache
- Irritability, poor temper control
- Loss of bladder control (urinary incontinence)
- Loss of coordination and trouble walking
- Muscle spasticity (spasm)
- Slow growth (child 0 – 5 years)
- Slow or restricted movement
- Vomiting
Signs and tests
The doctor or nurse will examine the baby.
This may show:
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- Stretched or swollen veins on the baby’s scalp
- Abnormal sounds when the health care provider taps lightly on the scull, suggesting a problem with the scull bones
- All or part of the head may be larger than normal, usually in the front part
- Eyes that looks “sunken in”
- White part of the eye appears over the colored area, making it look like a “setting sun”
- Reflexes may be normal
- Head circumference measurements, repeated over time, may show that the head is getting bigger.
A CT-scan of the head is one of the best tests for identifying hydrocephalus.
Other tests that may be done include:
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- Cranial ultrasound (an ultrasound of the brain)
- Lumbar puncture and examination of the cerebrospinal fluid (rarely done)
- Skull x-rays
- MRI
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Treatment
The goal of the treatment is to reduce or prevent brain damage by improving the flow of CSF.
Surgery may be done to remove a blockage, if possible.
If not, a flexible tube called a shunt may be placed in the brain to re-route the flow of CSF. The shunt sends CSF to another part of the body, such as the belly area, where it can be absorbed.
Other treatments may include:
Antibiotics are given if there are signs of infection. Severe infections may require the shunt to be removed
A procedure called endoscopic third ventriculostomy (ETV), which relieves pressure without replacing the shunt
Removing or burning away (cauterizing) the parts of the brain that produce CSF
The child will need regular check-ups to make sure there are no further problems. Tests are regularly done to check the child’s developmental and intellectual, neurological, or physical problems.
Visiting nurses, social services, support groups, and local agencies can provide emotional support and assist with the care of a child with hydrocephalus who has significant brain damage.
Expectations (prognosis)
Without treatment, up to 6 I 10 people with hydrocephalus will die. Those who survive have different amounts of intellectual, physical, and neurological disabilities.
The outlook depends on the cause. Hydrocephalus that is not due to an infection has the best outlook. Persons with hydrocephalus caused by tumours usually do very poorly.
Most children with hydrocephalus that survive for 1 year will have a fairly normal life span.
Complications
The shunt may become blocked. Symptoms of such a blockage include headache and vomiting. Surgeons may be able to help the shunt open without having to replace it.
There may be other problems with the shunt, such as kinking, tube separation, or infection in the area of the shunt.
Other complications may include:
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- Complications of surgery
- Infections such as meningitis or encephalitis
- Intellectual impairment
- Nerve damage (decrease in movement, sensation, function)
- Physical disabilities
