As people age, memory loss, bladder control issues and difficulty walking often become more noticeable. Because these issues are common symptoms in conditions like Parkinson's and Alzheimer's disease, a rare but treatable disorder called normal pressure hydrocephalus (NPH) may go unrecognized, untreated or misdiagnosed. Learn about NPH, how to recognize its hallmark symptoms and the treatment options that may help.

What Is Normal Pressure Hydrocephalus?

Normal pressure hydrocephalus (NPH) is a brain disorder where excess cerebrospinal fluid builds up in the brain’s ventricles, or fluid-filled spaces. Despite this buildup, fluid pressure often stays normal. As the ventricles enlarge, they press on nearby brain tissue, leading to walking difficulties, memory and thinking problems, and loss of bladder control.

NPH mainly affects people in their 60s and 70s. Because its symptoms mimic Alzheimer’s and Parkinson’s disease, it is often misdiagnosed. The Hydrocephalus Association estimates that nearly 700,000 adults have NPH, but fewer than 20 percent receive the correct diagnosis and treatment.

Signs and Symptoms of NPH

NPH has a distinct combination of symptoms that often appear together. Recognizing these signs early can help ensure proper diagnosis and treatment. Key symptoms to watch for include:

• Difficulty walking

Often described as feeling like walking “on a boat,” with the body bent forward, legs held wide apart and feet seeming “glued to the deck”

• Mild dementia

Includes forgetfulness, short-term memory loss and loss of interest in daily activities, as well as slower thinking, reduced concentration, impaired planning and decision-making, apathy and changes in personality or behavior.

• Loss of bladder control

Typically appears later in the disease, following walking and cognitive changes

How Is NPH Diagnosed?

Diagnosing normal pressure hydrocephalus involves a combination of tests and evaluations to confirm the condition and plan treatment. These include:

• Brain imaging

MRI or CT scans detect enlarged ventricles. In NPH, ventricles appear enlarged without overall brain tissue shrinkage, which helps differentiate it from conditions like Alzheimer’s disease.

• Clinical examination

An evaluation by a neurologist experienced in brain disorders affecting movement, thinking skills and physical function is essential, as NPH symptoms can overlap with other dementias.

• Cerebrospinal fluid (CSF) tests

Tests, such as lumbar puncture, external lumbar drainage, CSF outflow resistance measurement, intracranial pressure monitoring and isotopic cisternography, help predict responsiveness to shunt surgery and determine shunt pressure.

Treatment Options

NPH is often treated with ventriculoperitoneal (VP) shunting. This surgery uses general anesthesia to place a catheter into one of the brain’s ventricles. The catheter connects to a valve under the scalp, with tubing that drains excess fluid into the abdomen. Success rates vary widely, from about 33 to over 90 percent, depending on the patient. Many people see improvements in walking, bladder control and daily activities after surgery. However, there are risks, including bleeding in or around the brain, so careful evaluation is essential before treatment.

In Conclusion

Normal pressure hydrocephalus is a treatable condition and not just a part of aging. If you or someone you love is experiencing walking problems, memory loss or bladder issues, talk to your doctor about NPH to explore possible treatment options.