Complications of hydrocephalus 

Hydrocephalus (fluid on the brain) can cause complications, or complications may develop as a result of having surgery to treat it.

Shunt malfunction

A shunt is a delicate piece of equipment prone to malfunction, usually through blockage or infection. It's estimated that up to four out of 10 shunts will malfunction in the first year after surgery. Sometimes, a scan after the operation shows the shunt isn't in the best position, and that further surgery may be needed to reposition it.

If a baby or child has a shunt fitted, the shunt may become too small as your child grows, and it will need to be replaced. As most people need a shunt for the rest of their life, more than one replacement may be needed.

It's estimated that most children with hydrocephalus may have an average of two procedures for shunt problems before they're 10 years old.

Occasionally, bleeding can occur when shunt tubes are positioned. This can result in nerve problems, such as weakness down one side. There's also a small risk of fits following any type of brain surgery.

In younger children, particularly babies, cerebrospinal fluid (CSF) can run alongside the shunt rather than down it, and it can leak through the skin wound. If this occurs, further stitches will be needed to stop the leak.

Shunt blockage

A shunt blockage can be very serious because it can lead to an excess build-up of fluid on the brain, which can cause brain damage. This will cause the symptoms of hydrocephalus. Emergency surgery will be required to replace the malfunctioning shunt.

Shunt infection

Shunt infection is also a relatively common complication. The risk of infection can be around 3-15% and is more likely to occur during the first few months after surgery.

The symptoms of a shunt infection may include:

  • redness and tenderness along the line of the shunt
  • a high temperature (fever) of 38C (100.4F) or above
  • headache
  • being sick
  • neck stiffness
  • tummy pain (if the shunt drains into your tummy)
  • irritability or drowsiness in babies

Contact your care team immediately if you or your child has these symptoms. You may need a course of antibiotics to treat the infection and, in some cases, surgery may be required to replace the shunt.

Complications of endoscopic third ventriculostomy (ETV)

An endoscopic third ventriculostomy (ETV) is a surgical procedure to create a small hole in the floor of your brain. Complications can occur after this type of operation, such as:

  • the hole can close
  • your brain may not be able to absorb the cerebrospinal fluid that's now draining through it
  • you may develop an infection, although this is less likely than after shunt surgery
  • you may have bleeding inside your brain (this is usually minor)

If there's a problem with the hole, it may be possible to repeat the procedure, or you may need to have a shunt fitted (see treating hydrocephalus).

Other risks of ETV include nerve problems, such as weakness down one side of the body, double vision or hormone imbalances. Most nerve problems will get better, but there's a small risk of permanent problems. There's also a small risk of epilepsy, and a very small risk of an injury to one of the blood vessels in the brain, which may be fatal.

Long-term complications of congenital hydrocephalus

Many babies born with hydrocephalus (congenital hydrocephalus) have permanent brain damage. This can cause a number of long-term complications such as:


Shunt alert cards

Shine, the hydrocephalus and spina bifida charity, has produced a series of ‘shunt alert cards’ for adults and children. You carry the card with you if you've had a shunt fitted.

They're useful in a medical emergency if you have symptoms of a blockage or infection. The healthcare professionals treating you will be aware that you have a shunt fitted. They'll check whether this is causing your symptoms. 

To apply for a shunt alert card, you can either fill out a form on the Shine website or call 01733 555988.

Page last reviewed: 19/01/2015

Next review due: 19/01/2017