A Hydrocephalic condition is not confined to Spina Bifida . Hydrocephalus can result from other congenital conditions, disease, and even from head injuries. The classification discussed here is the congenital variety as it pertains to Spina Bifida.

Hydrocephalus is caused by a build up of cerebrospinal fluid which, in persons not affected, normally drains away. However in approximately 90% of Spina Bifida cases this natural drainage does not occur. Until the early 1960's, a baby born with Hydrocephalus would have been unlikely to survive as the build up of fluid, over time, will cause brain damage and swelling of the fontanelle.

The introduction of a small pressure relief valve, known as a shunt, to drain the excess fluid has led to those affected leading a more normal life. The shunt is surgically applied beneath the scalp, with a small catheter inserted into the brain and pipe draining the excess fluid into the abdominal cavity or the heart.

The presence of Hydrocephalus in conjunction with Spina Bifida almost invariably includes a number of cognitive and learning disorders. The degree of these disorders varies among individuals and can include problems with:

  • Memory
  • Fine motor skills
  • Initiation skills
  • Concentration and attention
  • Task management

For more information on the cognitive issues involved with Hydrocephalus, please refer to the excellent information pages on the Spina Bifida Association of Queensland's website relating to:

Possible symptoms of Hydrocephalus and/or shunt blockage

It is possible for shunts to become blocked, causing an increase in fluid pressure. Symptoms of this build up vary widely depending on the individual. Below is a list of possible symptoms to look for if you think there is a problem. If you are at all concerned, seek medical advice quickly from your paediatrician or neurosurgeon.

  • Vomiting or loss of appetite
  • Drowsiness
  • Eyes turning down or inward
  • Headache
  • Blurred vision
  • Poor concentration and memory
  • Fever
  • Irritability
  • Loss of coordination

Very young babies, who may not yet be fitted with a shunt, can show extreme physical symptoms. These may include:

  • Bulging and/or crossed eyes
  • Bulging fontanelle
  • Increased head size
  • Prominent veins in the forehead

If a person diagnosed with Hydrocephalus who has a shunt shows any of these symptoms, it should be assumed that the shunt is the problem until proven otherwise.

Shunt complications

There are three main complications that can occur:


Tissue or blood, protein or debris may block the shunt. This blockage may be partial, intermittent or continuous. In children it is possible for the shunt to become blocked in the course of the child's normal growth. It sometimes becomes necessary to extend the tube leading from the shunt to the abdomen as the child becomes taller. If a part of the shunt becomes blocked an operation may be necessary to replace the shunt.


Some shunts may become disconnected, requiring attention from a neurosurgeon.


Infection of the shunt can be caused by bacteria introduced from a number of possible sources. Antibiotics are used to treat such infection and it may be necessary to replace the shunt. The most common source of a shunt failure is infection of the shunt itself.

Remember it is extremely important to seek early medical advice.