Hydrocephalus versus NPH: What’s the Difference?
Understanding Normal Pressure Hydrocephalus (NPH) — Especially If You’re Under 60
If you’re experiencing memory problems, walking difficulties, or bladder issues, it’s natural to wonder: Could this be normal pressure hydrocephalus (NPH)? It’s also natural to wonder if you have NPH if you’ve had hydrocephalus your entire life and you feel your pressure is normal now because you’re treated.
Before assuming that’s what’s going on, it’s important to understand what NPH is and who it actually affects.
Know the Difference between Hydrocephalus and NPH
Hydrocephalus is the blanket term for a condition where excess cerebrospinal fluid (CSF) builds up in the brain’s ventricles, which can cause pressure and lead to a wide range of symptoms depending on the type, cause, and age of onset. One type of hydrocephalus is NPH.
What Is Normal Pressure Hydrocephalus (NPH)?
Normal pressure hydrocephalus (NPH) is a buildup of cerebrospinal fluid (CSF) that causes the ventricles to enlarge. Although pressures may fluctuate and a single measurement may appear normal, diagnosis is based on a combination of clinical symptoms, imaging findings, and CSF-removal testing.
iNPH is predominantly a disorder of adults over 60. In younger adults, NPH-like syndromes are uncommon and usually secondary to another cause (e.g., hemorrhage, infection, tumor).
If you’re under 60 or have been living with hydrocephalus your entire life, it’s much more likely that you have a different type of hydrocephalus, and knowing which one can give you confidence in being an advocate for yourself.
What Are the Symptoms of NPH?
NPH is typically identified by three hallmark symptoms, though they may not appear all at once or with the same severity:
- Walking Difficulties: Trouble walking or turning, difficulty taking the first step, balance issues, or falls
- Cognitive Changes: Problems with short-term memory, organizing or planning tasks, multitasking, attention, or feeling withdrawn
- Bladder Control Issues: Urinary urgency, accidents, or difficulty making it to the bathroom in time
These symptoms can resemble those of other age-related conditions like Alzheimer’s or Parkinson’s. But unlike those, NPH may improve with the placement of a shunt.
To learn more about normal pressure hydrocephalus (NPH) vs Alzheimer’s and Parkinson’s, click here.
What Type of Hydrocephalus Do I Have If I’m Under 60 or Have Been Living With it My Entire Life?
Doctors working with the adult hydrocephalus population are now beginning to classify forms of adult hydrocephalus, thanks to the research of the Adult Hydrocephalus Clinical Research Network (AHCRN). If you’re younger than 60 and dealing with hydrocephalus symptoms, you may have one of the following:
- Adults who are diagnosed and treated in childhood (transitioning(ed) adults)
- Present at birth or diagnosed in infancy or childhood
- Caused by genetic conditions, structural abnormalities, or prenatal complications
- Often associated with spina bifida, aqueductal stenosis, Dandy-Walker syndrome
- Treated in childhood either with a shunt, endoscopic third ventriculostomy (ETV), or both
- Adults newly diagnosed with Congenital Hydrocephalus
- Present at birth or very early in life, but often asymptomatic
- Caused by genetic conditions, structural abnormalities, or prenatal complications
- Some individuals go years without symptoms – either the fluid slowly builds up to a point where it affects the brain’s normal function or the fluid spaces (ventricles) in the brain can slowly become larger over time. This causes a subtle ongoing injury that gradually weakens the brain’s ability to compensate. Such cases are sometimes classified as decompensated congenital hydrocephalus.
- It is unclear as to why hydrocephalus can remain dormant for years, as some people don’t notice symptoms until adolescence or even adulthood.
- Adults who Acquire Hydrocephalus
- Acquired hydrocephalus is the form of hydrocephalus that develops any time after birth.
- Both children and adults can be diagnosed with acquired hydrocephalus. The most common causes are:
- Brain hemorrhage
- Brain tumor
- Infection (e.g., meningitis)
Communicating vs. Non-Communicating Hydrocephalus
- Communicating: CSF flows freely but isn’t properly absorbed
- Non-communicating (obstructive): CSF is physically blocked within the brain
- NOTE: These terms describe how CSF flows, not when the condition began
We see a lot of adults who have a normal head size but otherwise appear to have had asymptomatic hydrocephalus for possibly decades. We don’t really know the cause of why it manifested after the skull sutures have closed after/around age 2, but it presents similar to pure congenital, at-birth cases. We don’t really consider it acquired unless we can identify the cause.
Why It Might Seem Like NPH
People with asymptomatic or decompensated congenital hydrocephalus don’t experience symptoms until adulthood. You may have been symptom-free for years — and then start noticing:
- Brain fog or slowed thinking
- Trouble with balance or walking
- New or increased bladder urgency
These symptoms overlap with those seen in NPH, which can cause confusion. But in most cases, it’s not NPH — it’s a shift in your existing hydrocephalus. And for some of you, that may be hydrocephalus that you didn’t even know you have.
Either way, NPH is extremely unlikely if you’re under 60. The key is getting a comprehensive evaluation to understand your true history with the condition.
What Type of Hydrocephalus Do I Have?
Use this quick guide to better understand where your diagnosis might fall.
Always consult your doctor to confirm.
Step 1: Are you over 60 years old?
→ Yes
• Do you have walking problems, cognitive changes, and/or bladder symptoms?
→ If yes: Ask your doctor about normal pressure hydrocephalus (NPH)
→ If no: Your symptoms may be due to another condition or type of hydrocephalus
→ No
• Continue below
Step 2: Are you under 60 years old?
→ Yes
• Did your hydrocephalus begin in childhood, or after a brain bleed, infection, tumor, or injury?
→ If yes: You likely have congenital or acquired hydrocephalus
→ If not sure: Ask your doctor for clarification
What Should You Do If You’re Not Sure?
If you’ve been told you might have NPH or your diagnosis feels unclear, here are a few steps to take:
Ask your doctor:
- What type of hydrocephalus do I have?
- When was it first diagnosed?
- What caused it?
- How are we treating it?
For a list of questions to ask your doctor, click here.
Check or request your records:
- Imaging results (MRI or CT)
- Surgical reports
- Hospital discharge summaries
Get a second opinion:
Especially if your symptoms are changing or your diagnosis has never been well explained. A neurologist or neurosurgeon experienced in hydrocephalus can help clarify things. To learn more about second opinions, click here.
Find Support and Get Answers
You don’t have to figure this out alone. If you’re feeling unsure or overwhelmed, we’re here to help:
- Contact our support team for personalized guidance and answers
- Search our Physicians’ Directory to find neurosurgeons and neurologists with hydrocephalus experience
- Explore our Hydrocephalus Resource Library for trusted information, tools, and educational materials at every stage of life
What This Means for You
It’s important to know the type and cause of your hydrocephalus so that you can be an informed advocate for your care. As clinical researchers continue to define adult hydrocephalus, we encourage you to stay involved and connected to help us understand adult hydrocephalus and develop support and educational resources for you. One way to help is by joining our patient registry – HAPPIER. Find out more.
Information you can trust! This article was produced by the Hydrocephalus Association, copyright 2024. We would like to thank Abhay Moghekar, MBBS, for his valuable contribution and expert input.
This article is designed to provide helpful information on the subjects discussed. It is not intended as a substitute for treatment advice from a medical professional. For diagnosis or treatment of any medical condition, consult your doctor.