• Inside everyone's brain there is a clear fluid called cerebrospinal fluid or CSF for short.
• The CSF is made inside spaces in the brain called “ventricles”. The CSF flows out over the surface of the brain and down the channel in the middle of the backbone (spinal column) to bathe and protect the brain and spinal cord. Then the fluid is absorbed into the bloodstream.
• Hydrocephalus happens when this fluid cannot drain away into the bloodstream because the normal pathways are blocked. As the fluid is still being made by the brain, the build up of CSF will cause pressure to rise inside the brain and this can lead to damage.
• Hydrocephalus is known as water on the brain.

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