Hydrocephalus is usually referred to as "water on the brain" by the general public. The water in hydrocephalus is really cerebrospinal fluid (CSF), which has accumulated in the brain as a result of an imbalance in the amount of CSF produced versus the amount the body can absorb. CSF normally travels through the brain cavities continuously, acting as a shock absorber and supplying critical nutrients before being absorbed into the bloodstream. The proper flow of CSF is disrupted by hydrocephalus, resulting in an accumulation of CSF that puts pressure on the brain.