Hydrocephalus refers to a build-up of fluid inside the skull, leading to brain swelling. Hydrocephalus means "water on the brain."
Normal pressure hydrocephalus (NPH) is a rise in cerebrospinal fluid (CSF) in the brain that affects brain function. However, the pressure of the fluid is usually normal.
Hydrocephalus - idiopathic; Hydrocephalus - adult; Hydrocephalus - communicating; Extraventricular obstructive hydrocephalus
Normal pressure hydrocephalus (NPH) is a form of hydrocephalus, which means there is too much fluid pressing on the brain.
NPH can occur without a known cause, or it may be caused by any condition that blocks the flow of cerebrospinal fluid (CSF). The fluid-filled chambers (ventricles) of the brain enlarge to fit the increased volume of CSF. They press down on and damage or destroy brain tissue.
Risk factors include:
CSF is produced in normal amounts in these conditions, but it is prevented from being reabsorbed normally.
NPH is thought to account for about 5% of all dementias.
The symptoms often begin slowly.
A person needs to have three symptoms to be diagnosed with normal pressure hydrocephalus:
Sudden falls without a loss of consciousness or other symptoms (drop attacks) may occur early in the illness.
Note: Many of these symptoms are common in the elderly, and may be caused by other conditions.
An examination shows walking (gait) changes related to the pressure placed on parts of the brain. Deep tendon reflexes may be increased in the lower legs.
Some patients improve a lot after this surgery, but many do not. Walking is the symptom most likely to improve. No specific symptoms or test results can accurately predict which patients are most likely to get better after surgery.
See: Dementia - homecare for information about taking care of a loved one with dementia.
Without treatment, symptoms often get worse and could lead to death.
Surgical treatment improves symptoms in a percentage of patients. People with minimal symptoms have the best outcome.
Call your health care provider if:
Go to the emergency room or call the local emergency number (such as 911) if a sudden change in mental status occurs. This may mean that another disorder has developed.
Rosenberg GA. Brain edema and disorders of cerebrospinal fluid circulation. In: Bradley WG, Daroff RB, Fenichel GM, Jankovic J, eds. Neurology in Clinical Practice. 5th ed. Philadelphia, Pa: Butterworth-Heinemann; 2008:chap 63.