Normal pressure hydrocephalus
Hydrocephalus - occult; Hydrocephalus - idiopathic; Hydrocephalus - adult; Hydrocephalus - communicating; Dementia - hydrocephalus; NPH
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 cerebrospinal fluid (CSF) in the brain that affects brain function. However, the pressure of the fluid is usually normal.
Causes
There is no known cause for NPH. But the chance of developing NPH is high in someone who has had any of the following:
-
Bleeding from a blood vessel or
aneurysm
in the brain (
subarachnoid hemorrhage
)
Aneurysm
An aneurysm is a weak area in the wall of a blood vessel that causes the blood vessel to bulge or balloon out. When an aneurysm occurs in a blood ve...
Subarachnoid hemorrhage
Subarachnoid hemorrhage is bleeding in the area between the brain and the thin tissues that cover the brain. This area is called the subarachnoid sp...
- Certain head injuries
-
Meningitis
or similar infections
Meningitis
Meningitis is an infection of the membranes covering the brain and spinal cord. This covering is called the meninges.
-
Surgery on the brain (
craniotomy
)
Craniotomy
Brain surgery is an operation to treat problems in the brain and surrounding structures.
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
Symptoms of NPH often begin slowly. There are 3 main symptoms of NPH:
- Changes in the way a person walks: difficulty when beginning to walk (gait apraxia), feel as if they are stuck to the ground (magnetic gait)
- Slowing of mental function: forgetfulness, difficulty paying attention, apathy or no mood
-
Problems controlling urine (
urinary incontinence
), and sometimes controlling stools (
bowel incontinence
)
Urinary incontinence
Urinary (or bladder) incontinence happens when you are not able to keep urine from leaking out of your urethra. The urethra is the tube that carries...
Bowel incontinence
Bowel incontinence is the loss of bowel control, causing you to pass stool unexpectedly. This can range from sometimes leaking a small amount of sto...
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:
-
Lumbar puncture
(spinal tap) with careful testing of walking before and right after the spinal tap
Lumbar puncture
Cerebrospinal fluid (CSF) collection is a test to look at the fluid that surrounds the brain and spinal cord. CSF acts as a cushion, protecting the b...
-
Head CT scan
or
MRI of the head
Head CT scan
A head computed tomography (CT) scan uses many x-rays to create pictures of the head, including the skull, brain, eye sockets, and sinuses.
MRI of the head
A head MRI (magnetic resonance imaging) is an imaging test that uses powerful magnets and radio waves to create pictures of the brain and surrounding...
Treatment
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 .
Ventricoperitoneal shunt
Ventriculoperitoneal shunting is surgery to treat excess cerebrospinal fluid (CSF) in the brain (hydrocephalus).
Outlook (Prognosis)
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.
Possible Complications
Problems that may result from NPH or its treatment include:
- Complications of surgery (infection, bleeding, shunt that does not work well)
-
Loss of brain function (
dementia
) that becomes worse over time
Dementia
Dementia is a loss of brain function that occurs with certain diseases. It affects memory, thinking, language, judgment, and behavior.
- 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.
Change in mental status
Confusion is the inability to think as clearly or quickly as you normally do. You may feel disoriented and have difficulty paying attention, remembe...
References
Ferri FF. Normal pressure hydrocephalus. In: Ferri FF, ed. Ferri's Clinical Advisor 2016 . Philadelphia, PA: Elsevier; 2016:chap 648.
Rosenberg GA. Brain edema and disorders of cerebrospinal fluid circulation. In: Daroff RB, Jankovic J, Mazziotta JC, Pomeroy SK, eds. Bradley's Neurology in Clinical Practice . 7th ed. Philadelphia, PA: Elsevier; 2016:chap 88.
-
Central nervous system - illustration
The central nervous system is comprised of the brain and spinal cord. The peripheral nervous system includes all peripheral nerves.
Central nervous system
illustration
-
Ventricles of the brain - illustration
The ventricles of the brain are hollow chambers filled with cerebrospinal fluid (CSF), which supports the tissues of the brain.
Ventricles of the brain
illustration
-
Central nervous system - illustration
The central nervous system is comprised of the brain and spinal cord. The peripheral nervous system includes all peripheral nerves.
Central nervous system
illustration
-
Ventricles of the brain - illustration
The ventricles of the brain are hollow chambers filled with cerebrospinal fluid (CSF), which supports the tissues of the brain.
Ventricles of the brain
illustration
Review Date: 2/27/2016
Reviewed By: Amit M. Shelat, DO, FACP, Attending Neurologist and Assistant Professor of Clinical Neurology, SUNY Stony Brook, School of Medicine, Stony Brook, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.