The brain and spinal cord are surrounded by a clear fluid known as cerebrospinal fluid (CSF). This fluid is made and stored in cavities in the brain called ventricles. CSF is critical to the proper function of the brain and spinal cord. It remains in a closed-circuit loop to protect the brain and spinal cord from infection. CSF also supplies the brain and spinal cord with nutrients and removes some of the waste products that may accumulate over time. Patients quickly perceive the slightest change in CSF pressure.
Hydrocephalus is the condition in which there is too much CSF in the ventricles caused by a malfunction in the draining and absorbing systems. When too much fluid collects in the ventricles they will enlarge to accommodate the extra fluid. This enlargement puts pressure on the brain causing numerous symptoms.
Normal pressure hydrocephalus (NPH) is a type of hydrocephalus that occurs mainly in adults over the age of 60. NPH develops slowly over time; therefore changes are subtle or less noticeable. The fluid pressure builds up gradually in the ventricles which causes pressure to increase in the brain.