Paediatric hydrocephalus is a condition caused by an excessive build-up of cerebral spinal fluid (CSF) in the brain. CSF is a clear fluid that surrounds and cushions the brain and spinal cord, protecting them from injury. When the fluid builds up in the brain, it can cause increased pressure within the head. Hydrocephalus can occur for a variety of reasons. Sometimes, it is caused by an overproduction of CSF and other times, it may be due to the body’s inability to drain or reabsorb the fluid. It can be present at birth (congenital) or occur after birth (acquired). Paediatric hydrocephalus can be damaging if left untreated, but with early diagnosis and treatment, children with hydrocephalus can often lead normal, healthy lives.
What are the causes of hydrocephalus?
Hydrocephalus may be congenital (born with it) or acquired (developed).
When hydrocephalus is congenital, it may be the result of a condition like spina bifida, where the baby’s spine does not form normally, or aqueductal stenosis, a narrowing of the passage between the third and fourth ventricles in the brain. Hydrocephalus may also be caused by a genetic disorder.
Acquired hydrocephalus occurs any time after birth. It may occur due to bleeding in the brain, sometimes seen in premature babies or in individuals who have experienced traumatic brain injuries. It may occur if there is a growing mass causing obstruction to the flow of CSF. Sometimes it may be idiopathic, which means that it develops without a known cause.
What are the signs and symptoms of hydrocephalus?
The signs and symptoms vary between individuals and can present differently based on age.
During pregnancy, a routine ultrasound may detect hydrocephalus in the baby.
In young babies, the skull bones are not yet fused together and there are soft spots, called fontanelles, between the bones. The most common sign of hydrocephalus in an infant is typically a large head or firm, bulging fontanelles.
Signs or symptoms of hydrocephalus in infancy may include:
- Bulging fontanelles (soft spots between the bones)
- A large head circumference or a rapid increase in head growth
- Swollen veins on the scalp
- Difficulty looking upward during eye movements
- Repetitive vomiting
- Excessive irritability, possibly due to head pain
- Very sleepy and difficult to awaken
- Seizures
Older children and adults will not have head growth with hydrocephalus and so they often display signs of increased head pressure. Headaches are the most common complaint.
Signs or symptoms of hydrocephalus in older children and adults may include:
- Headaches
- Nausea/vomiting
- Sleepiness
- Difficulty with motor skills or balance
- Blurry or double vision
- Incontinence
- Difficulty looking upward during eye movements
- Seizures
If left untreated, hydrocephalus can cause developmental delays, personality changes and
memory loss. In severe cases, untreated hydrocephalus may result in nerve damage, vision loss and even death. However, with prompt diagnosis and treatment, many infants and children with hydrocephalus are able to successfully manage their condition and lead long, healthy lives.
How is hydrocephalus diagnosed?
Hydrocephalus has traditionally been diagnosed after birth. Now, with advances in ultrasound technique, it is sometimes diagnosed while the baby is still in the womb. An ultrasound may show that the baby has large ventricles, the normal fluid-filled spaces in the brain. If hydrocephalus is suspected during pregnancy, your doctor will perform additional ultrasounds to monitor the size of the ventricles throughout the pregnancy.
After birth, hydrocephalus may be diagnosed with an ultrasound, a CT (computed tomography) or an MRI (
magnetic resonance imaging).
What are the treatment options for hydrocephalus?
Hydrocephalus is the most common reason for
brain surgery in children. Treatment for hydrocephalus varies based on the age of the child and the cause of the hydrocephalus. The most common treatment options are placement of a shunt or performing a third ventriculostomy.
A shunt is a long, flexible tube that helps to redirect the flow of CSF. Generally, one end is placed in the ventricle of the brain and the other end is placed in the peritoneal space, an abdominal cavity. This is called a ventriculo-peritoneal shunt. Sometimes, the lower end of the shunt may be placed into a chamber in the heart or the space around the lungs. The shunt has a valve that directs the flow of CSF away from the brain.
When a child has a shunt, there is a risk for a shunt malfunction. This means that the shunt is not working and fluid is building up in the brain. This may occur if the shunt becomes blocked or if the pieces of the shunt become disconnected in the body. Generally, the child will then experience the
signs and symptoms of hydrocephalus mentioned above.
Another surgical option is an endoscopic third ventriculostomy. It is helpful for patients that have a blockage of CSF. In this surgery, a small opening is made in the bottom of the third ventricle, allowing the CSF to leave the brain by a different route. This is a minimally-invasive approach as surgeons use a small, lighted camera (an endoscope) to view the surgical site. This procedure may allow a child to live without a shunt, however, there is the possibility that the small opening may close on its own. If this occurs, the child will experience the signs and symptoms of hydrocephalus once again.
Can hydrocephalus be prevented?
Most forms of hydrocephalus cannot be prevented. However, it’s recommended that parents protect their children from head injuries by doing things such as using proper car seats or seatbelts, childproofing around the house to prevent falls and ensuring children have proper helmets for sports and activities.