Hydrocephalus is a buildup of spinal fluid inside the fluid chambers of the brain. Hydrocephalus means "water on the brain."
Normal pressure hydrocephalus (NPH) is a rise in the amount of cerebrospinal fluid (CSF) in the brain that affects brain function. However, the pressure of the fluid is usually normal.
Hydrocephalus - occult; Hydrocephalus - idiopathic; Hydrocephalus - adult; Hydrocephalus - communicating; Dementia - hydrocephalus; NPH
There is no known cause for NPH. But the chance of developing NPH is high in someone who has had any of the following:
As CSF builds up in the brain, the fluid-filled chambers (ventricles) of the brain swell. This causes pressure on brain tissue. This can damage or destroy parts of the brain.
Symptoms of NPH often begin slowly. There are three main symptoms of NPH:
Diagnosis of NPH can be made if any of the above symptoms occur and NPH is suspected and testing is done.
The health care provider will perform a physical examination and ask about the symptoms. If you have NPH, the provider will likely find that your walking (gait) is not normal. You may also have memory problems.
Tests that may be done include:
Treatment for NPH usually requires surgery to place a tube called a shunt that routes the excess CSF out of the brain ventricles and into the abdomen. This is called a ventriculoperitoneal shunt.
Without treatment, symptoms often get worse and could lead to death.
Surgery improves symptoms in some people. Those with mild symptoms have the best outcome. Walking is the symptom most likely to improve.
Problems that may result from NPH or its treatment include:
Call your provider if:
Go to the emergency room or call 911 or the local emergency number if a sudden change in mental status occurs. This may mean that another disorder has developed.
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Rosenberg GA. Brain edema and disorders of cerebrospinal fluid circulation. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds. Bradley and Daroff's Neurology in Clinical Practice. 8th ed. Philadelphia, PA: Elsevier; 2022:chap 88.
Sivakumar W, Drake JM, Riva-Cambrin J. The role of endoscopic third ventriculostomy: a critical review. In: Winn HR, ed. Youmans and Winn Neurological Surgery. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 45.
Reviewed By: Joseph V. Campellone, MD, Department of Neurology, Cooper Medical School at Rowan University, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.