Normal Pressure Hydrocephalus Overview

Symptoms, Diagnosis, Treatment and Prognosis

Normal pressure hydrocephalus (NPH) is a condition caused by the buildup of cerebrospinal fluid (fluid typically found in the spinal cord and brain) primarily in the brain's ventricles. Hydrocephalus, in fact, means "water on the brain."

The fluid buildup occurs when there is a block in the flow or absorption of the cerebrospinal fluid. Often, despite the fluid buildup, there is little or no increase in the pressure inside the skull, thus the name "normal" pressure hydrocephalus. The term dates back to Dr. Salomon Hakim’s paper in 1964, where he first described the phenomenon of cerebrospinal fluid buildup.

NPH is often misdiagnosed as Alzheimer’s, Parkinson’s or Creutzfeldt-Jakob disease because the symptoms overlap.

Illustration of brain with faucet
LAGUNA DESIGN Science Photo Library / Getty Images

Causes

The National Institute of Neurological Disorders and Stroke details the congenital and acquired causes of normal pressure hydrocephalus. Some of those causes include:

  • Inherited genetic abnormalities and developmental disorders connected to birth defects in the brain, spine, or spinal cord
  • Premature birth complications
  • Fetal infection that causes brain tissue inflammation, including rubella
  • Tumors on the brain or spinal cord
  • Central nervous system infection, including bacterial meningitis
  • Bleeding on the brain due to injury or stroke

Symptoms

The National Institute of Neurological Disorders (NINDS) describes that the symptoms of hydrocephalus vary significantly for each patient, especially depending on age. The following symptoms based on age include:

Infants

  • Rapid increase in head size
  • Unusually large head
  • Bulge on the soft spot (fontanel) on the top of the head
  • Vomiting
  • Problems sucking or feeding
  • Sleepiness
  • Irritability
  • Eyes that are fixed downward (also called "sun setting") or are not able to turn outward
  • Seizures.

Older Children, Young Adults, Middle-Aged Adults

  • Headache
  • Blurred or double vision
  • Nausea or vomiting
  • Problems with balance
  • Slowing or loss of developmental progress like walking or talking
  • Vision problems
  • Decline in school or job performance
  • Poor coordination
  • Loss of bladder control and/or frequent urination
  • Difficulty remaining awake or waking up
  • Sleepiness
  • Irritability
  • Changes in personality or cognition including memory loss

Older Adults

  • Problems walking, often described as feet feeling "stuck"
  • Progressive mental impairment and dementia
  • General slowing of movements
  • Loss of bladder control and/or frequent urination
  • Poor coordination and balance

How NPH Differs From Alzheimer’s

The initial symptoms of NPH are usually the three outlined above. Alzheimer’s symptoms, on the other hand, start out primarily as cognitive issues, such as decreased short-term memory and difficulty learning new things. Incontinence and problems with the ability to move around often do develop as Alzheimer’s progresses, but they are not typical symptoms in the early stages of Alzheimer’s.

It is also possible to have both NPH and Alzheimer’s at the same time, which makes diagnosis and treatment challenging.

Diagnosis

A diagnosis of NPH is considered when a person has impairment in walking and balance in addition to either incontinence or cognitive dysfunction. NPH is diagnosed usually by a neurologist or a neurosurgeon through several tests, which may include the following, according to the Hydrocephalus Association :

  • Brain imaging, including CT, MRI, and cisternography,
  • Neurological testing including memory, mood, and reasoning assessments
  • Lumbar imaging and testing including puncture and drainage procedures, and pressure monitoring
  • Cerebrospinal fluid (CSF) test to examine the pressure of liquid on the brain

Treatment

Treatment usually consists of inserting a shunt into the brain ventricle to drain extra fluid through a small catheter; however there are other types of treatment, according to NINDS.

When a shunt is not successful, an endoscopic third ventriculostomy (ETV) can help CSF flow out of the brain by a hole in the bottom of the third ventricle created by a surgeon. NINDS reports this can be "done in conjunction with choroid plexus cauterization to try and decrease the production of CSF" if needed.  

In addition, medications such as acetazolamide are sometimes used to treat NPH.

Prognosis

The prognosis varies with NPH. Early diagnosis is imperative. While some individuals don’t improve much with shunt placement, others make almost a full recovery if NPH is diagnosed and treated early. Typically, the walking gait of the individual is the first to improve, and the cognitive functioning is the last to improve, if it does.

4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Graff-Radford NR, Jones DT. Normal pressure hydrocephalus: CONTINUUM: Lifelong Learning in Neurology. 2019;25(1):165-186. doi. 10.1212/CON.0000000000000689. Published January, 2019.

  2. Pedro MKF, Silva JFC da, Rocha SFB da, et al. Salomón Hakim: the man behind normal pressure hydrocephalusArq Neuro-Psiquiatr. 2019;77(10):746-748. doi. 10.1590/0004-282x20190096. Published October, 2019.

  3. Müller‐Schmitz K, Krasavina‐Loka N, Yardimci T, et al. Normal pressure hydrocephalus associated with alzheimer’s diseaseAnn Neurol. 2020;88(4):703-711. doi: 10.1002/ana.25847. Published October, 2020.

  4. Kang MJ, Park YH, Kim S, Yi S. Hydrocephalus in a patient with alzheimer’s disease. Dement Neurocognitive Disorders. 2018;17(1):32. doi. 10.12779/dnd.2018.17.1.32. Published March, 2018.

Additional Reading
  • Alzheimer’s Association. Normal Pressure Hydrocephalus.

  • Hydrocephalus Association. Normal Pressure Hydorcephalus.

  • Life NPH. Diagnosis of NPH.

  • MedlinePlus.gov. Normal Pressure Hydrocephalus.

  • National Institute of Neurological Disorders and Stroke. National Institutes of Health. Normal Pressure Hydrocephalus Information Page.

  • Shprecher, David, Schwalb, Jason, and Kurlan, Roger. Current Neurology and Neuroscience Reports Normal Pressure Hydrocephalus: Diagnosis and Treatment.

  • UCLA Health System. UCLA Neurosurgery. Normal Pressure Hydrocephalus.

By Esther Heerema, MSW
Esther Heerema, MSW, shares practical tips gained from working with hundreds of people whose lives are touched by Alzheimer's disease and other kinds of dementia.