Normal Pressure Hydrocephalus: Symptoms, Tests and Shunt Surgery

What Is Normal Pressure Hydrocephalus?

Normal pressure hydrocephalus (NPH) is a slow build-up of fluid inside the brain. It mostly affects people over 60 and changes walking first, then bladder control and thinking. Unlike Alzheimer's disease, however, NPH can often improve with treatment, usually a shunt.

The fluid, called cerebrospinal fluid (CSF), cushions the brain and spinal cord. Normally, the body absorbs it as fast as it makes it. In NPH, however, it drains too slowly, so the brain's fluid spaces (ventricles) widen.

Despite the name, pressure readings usually stay in the normal range (NINDS). Most often, doctors find no clear cause (MedlinePlus). NPH can also follow a bleed from a brain aneurysm, a head injury or meningitis.

At a Glance

• Who it affectsMostly people over 60, with a slow start
• First signA slow, shuffling walk, as if the feet stick to the floor
• Key testsA brain MRI, then a tap test that removes some spinal fluid
• Main treatmentA shunt with a programmable valve, adjustable from outside
• Likely gainsWalking improves most often; memory less predictably
• Flying homeUK guidance advises about 7 days after brain surgery

What Brought You Here?

First, pick the line that fits you or your parent. Each one then leads to the matching part of this guide.

1. 01Walking has become slow, shuffling or unsteadyFeet that seem stuck to the floor, and falls when turning→
2. 02A parent seems slower, forgetful or withdrawnThinking changes that NPH can cause→
3. 03Sudden urges to pass urine, or accidentsBladder changes that often follow the walking problem→
4. 04A diagnosis of dementia or Parkinson's that does not quite fitHow doctors tell NPH apart from look-alikes→
5. 05A scan report that mentions enlarged ventriclesWhat the MRI and the tap test show→
6. 06Planning shunt surgery from abroadLength of stay, flights and valve checks at home→

Normal Pressure Hydrocephalus Symptoms

NPH affects three things: walking, bladder control and thinking. The changes usually build up slowly, over months or years (NHS). Not everyone, however, has all three.

Questions at this stage

When to See a Doctor About NPH Symptoms

NPH develops slowly, so it rarely needs emergency care. Early treatment, however, improves the chance of a good recovery (NINDS). Sudden changes, in contrast, point to another problem and need urgent help.

A sudden change in mental state may mean that another disorder has developed (MedlinePlus). So call 911 in the US and Canada, 999 in the UK or 112 in Europe.

NPH, Alzheimer's, Parkinson's or a Spine Problem?

NPH resembles more common conditions, so it often goes unrecognized (NINDS). The order of symptoms gives the first clue: in NPH, walking changes before memory.

How Doctors Tell Them Apart

First, the neurosurgeon asks which problem came first and how fast each one grew. Next, an MRI shows whether the ventricles look too wide for the brain. Then a tap test shows whether removing fluid improves the walk.

NPH and Alzheimer's disease can also occur together. In that case, however, a shunt may help walking more than memory.

Other Look-Alikes

If leg pain cuts the walk short, read about narrowing of the lower spinal canal. Clumsy hands point instead to cervical myelopathy, pressure on the spinal cord in the neck.

In contrast, severe headaches with blurred vision suggest pseudotumor cerebri. For Parkinson's disease, medicines come first, and deep brain stimulation helps selected patients.

How Doctors Diagnose NPH: MRI and the Tap Test

No single test proves NPH. Instead, doctors combine the symptoms, a brain scan and a spinal fluid test (NHS). Together, they then show who will likely benefit from a shunt.

Brain MRI

First, an MRI shows how wide the ventricles have become. It also rules out other causes, such as a brain tumor or a blocked channel. Prof. Albayrak measures their width on a high-resolution MRI, using the Evans index.

The Lumbar Tap Test

In a tap test, a thin needle in the lower back removes some spinal fluid. In Prof. Albayrak's practice, that means about 30-40 ml (1 to 1.4 fluid ounces). The team tests walking before the tap and again afterward (MedlinePlus).

So if walking clearly improves within a few hours, a shunt is likely to help. A test without change, however, does not always rule NPH out. Some people then need a longer test.

Lumbar Drain and Infusion Tests

The NHS also describes two further tests. First, a lumbar drain removes fluid through a thin tube over a few days. An infusion test, in contrast, measures how well the body absorbs added fluid.

Ruling Out Other Causes

Thyroid problems, low vitamin levels and medicine side effects can also mimic dementia (NIA). So blood tests and a memory assessment often form part of the work-up.

Normal Pressure Hydrocephalus Treatment Options

A shunt is the main treatment for NPH (MedlinePlus). Other options, however, either help briefly or suit only a few people. Not everyone with NPH benefits from surgery, so tests come first (NHS).

This guide focuses on NPH. For other types, see our hydrocephalus treatment guide, which explains ETV in detail.

Who Benefits From a Shunt?

Milder symptoms also predict a better result, according to MedlinePlus. Older age alone, however, does not settle the question. Instead, Prof. Albayrak weighs overall health, the test results and the anesthesia risk.

NPH Shunt Surgery: Step by Step

Prof. Albayrak treats NPH with a ventriculoperitoneal (VP) shunt and a programmable valve. The whole system lies under the skin and carries extra fluid to the belly. There, the body absorbs it.

He usually operates under general anesthesia. Beforehand, your team may pause blood thinners for some days (MedlinePlus).

1. The team shaves a small patch of hair, usually behind the ear.
2. Through a small opening in the skull, the surgeon places a thin tube in a ventricle.
3. A valve under the scalp, usually behind the ear, connects this tube to a second one.
4. The second tube runs under the skin of the neck and chest down to the belly.
5. Finally, the surgeon closes the small cuts on the head and the belly.

Why a Programmable Valve?

The valve controls how fast fluid drains. With a programmable valve, the surgeon resets it through the skin with a magnet. So the change needs no new operation (FDA).

This matters especially in NPH, because the right setting can shift over time. Too much drainage can cause headaches or a bleed between the brain and skull (FDA). Too little, in contrast, lets the old symptoms return.

The setting may therefore need fine-tuning after surgery, for example if headaches appear. Prof. Albayrak then adjusts it from outside, with a magnet.

What Are the Risks of NPH Shunt Surgery?

Shunt surgery carries real risks, and age and other illnesses can add to them. The most common problems are infection, blockage and draining too much or too little (FDA).

• Infection, most often in the first few months (NHS)
• A blocked, broken or disconnected tube (FDA)
• Over-drainage: headaches, or a bleed between the brain and skull (subdural hematoma)
• Under-drainage: walking, bladder or memory problems come back
• Bleeding in the brain, seizures or, rarely, injury to the bowel (MedlinePlus)
• General risks of anesthesia, such as breathing problems or blood clots

Many drainage problems respond to a new valve setting, so they need no surgery (FDA). A blocked or infected shunt, however, often needs an operation to replace a part. To lower the risk of infection, Prof. Albayrak uses shunt tubing that contains an antibiotic.

Recovery and Results After NPH Shunt Surgery

Most people stay in hospital for a few days after shunt surgery (NHS). In Prof. Albayrak's experience, walking usually improves first. Bladder control and thinking then follow, often more slowly.

A Typical Timeline

Physiotherapy helps people use their new walking ability safely. For this reason, Prof. Albayrak adds a physiotherapy program after the shunt.

Coming to Istanbul from the US, Canada, the UK or Europe

Plan the trip around the tests, a short hospital stay and a safe flight home. Older patients should also travel with a companion who knows their symptoms.

How Long to Stay in Istanbul

First come the consultation, any new scans and the tap test. The tap test takes several hours, with walking tests before and after. A lumbar drain, if your surgeon advises one, also adds a few days in hospital.

Then follow the operation, a few days on the ward and rest nearby. So, counting about 7 days before the flight, plan for roughly two weeks in Istanbul. Also keep the return date flexible.

Flying Home After Shunt Surgery

UK aviation guidance advises about 7 days between neurosurgery and a flight (CAA). Air left inside the skull can expand at altitude. Flying after surgery also raises the risk of blood clots (CDC).

Your neurosurgeon then confirms the date after a check-up. Also book wheelchair help at both airports, and choose an aisle seat.

Valve Settings After You Return Home

Before discharge, ask for a valve card with the make, model and current setting. Only an X-ray or a shunt checker confirms the setting (FDA). Each checker, moreover, works only with valves from the same maker.

So before you travel, find a neurosurgery team near home that can check your valve. After any MRI, ask for a valve check too. The scanner's magnet can change the setting (FDA).

For magnets in daily life, see living with a shunt in our hydrocephalus guide.

Follow-Up at Home

Take home the discharge summary, the operation note and copies of the scans. The CDC also advises getting copies of all records before you return. Ideally, book a visit with a neurosurgeon near home before you leave for Istanbul.

UK drivers must stop driving after shunt surgery and tell the DVLA. Relicensing may follow after 6 months if no lasting problem affects driving (GOV.UK). In the US and Canada, rules vary, so ask your doctor.

For insurance and Medicare, see brain surgery in Turkey: planning from the US. For NHS rules and travel insurance, see planning from the UK. From Canada, check with your provincial health plan and private insurer before you book.

Your NPH Surgeon in Istanbul

Prof. Dr. Serdar Baki Albayrak

Neurosurgeon · Full Professor of Neurosurgery

Prof. Albayrak bases the shunt decision on three findings: symptoms, MRI and the tap test. He uses programmable valves, so the setting can change later without another operation.

He completed his neurosurgery training at Istanbul University in 2004. Clinical fellowships then followed at the University of Helsinki and Harvard Medical School.

At Harvard, he trained at Brigham and Women's Hospital. Consultations take place in English or Turkish.

27+Years

5,000+Operations

64Countries

33Publications

Figures from Prof. Albayrak's professional profile, September 2026. See his full publication list.

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