The surgery used to treat hydrocephalus (excess fluid in the brain) can cause complications.

Shunt problems

A shunt is a delicate piece of equipment that can malfunction, usually by becoming blocked or infected.

Sometimes, a scan after the operation shows the shunt is not in the best position and further surgery is needed to reposition it.

If a baby or child has a shunt fitted, the shunt may become too small as the 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.

There can occasionally be bleeding when a shunt is positioned. This can cause nerve problems, such as weakness down one side. There's also a small risk of fits after any type of brain surgery.

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

Shunt blockage

A shunt blockage can be very serious as it can lead to a build-up of excess fluid in the brain, which can cause brain damage. This will cause the symptoms of hydrocephalus.

Emergency surgery will be needed to replace the malfunctioning shunt.

Shunt infection

Shunt infection is also a relatively common complication after shunt surgery. Infections are more likely to develop during the first few months after surgery.

The symptoms of a shunt infection may include:

Contact your care team immediately if you or your child has these symptoms. 

Antibiotics may be needed to treat the infection and, in some cases, surgery may be required to replace the shunt.

Shunt alert cards

The hydrocephalus and spina bifida charity Shine 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.

The card is 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 and will check whether this is causing your symptoms.

To apply for a shunt alert card, you can fill out a form on the Shine website or call 01733 555 988.

Complications of endoscopic third ventriculostomy (ETV)

An endoscopic third ventriculostomy (ETV) is surgery to create a small hole in the floor of the brain to drain the cerebrospinal fluid (CSF).

Possible complications after ETV surgery include:

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.

Other risks of ETV include nerve problems, such as weakness down 1 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 a blood vessel in the brain, which may be fatal.

Page last reviewed: 6 February 2023
Next review due: 6 February 2026