URL of this page: //www.nlm.nih.gov/medlineplus/ency/article/000752.htm

Normal pressure hydrocephalus

Hydrocephalus is a buildup of fluid inside the skull, which leads 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.


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 fluid 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:

  • Changes in the way a person walks: difficulty when beginning to walk (gait apraxia), feet held wider apart than normal, shuffling of the feet, unsteadiness
  • Slowing of mental function: forgetfulness, difficulty paying attention, apathy or no mood
  • Problems controlling urine (urinary incontinence), and sometimes controlling stools (fecal incontinence)

Diagnosis of NPH can be made if any of the above symptoms occur and NPH is suspected and testing is done.

Exams and Tests

The doctor will perform a physical examination and ask about the symptoms. If you have NPH, the doctor 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 is usually surgery to place a tube called a shunt that routes the excess CSF out of the brain ventricles. This is called a ventricoperitoneal shunt.

Outlook (Prognosis)

Without treatment, symptoms often get worse and could lead to death.

Surgery improves symptoms in some patients. Persons with mild symptoms have the best outcome. Walking is the symptom most likely to improve.

Possible Complications

  • Complications of surgery (infection, bleeding, shunt that does not work well)
  • Loss of brain function (dementia) that becomes worse over time
  • Injury from falls
  • Shortened life span

When to Contact a Medical Professional

Call your health care provider if:

  • You or a loved one is having increasing problems with memory, walking, or urine incontinence
  • A person with NPH worsens to the point where you are unable to care for the person yourself.

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.

Alternative Names

Hydrocephalus - idiopathic; Hydrocephalus - adult; Hydrocephalus - communicating


Rosenberg GA. Brain edema and disorders of cerebrospinal fluid circulation In: Daroff RB, Fenichel GM, Jankovic J, Mazziotta JC, eds.Bradley's Neurology in Clinical Practice.

Rosseau G. Normal pressure hydrocephalus. Dis Mon.

Update Date 2/24/2014

Related MedlinePlus Health Topics