With the Baby Boomers aging the number of people living with dementia is expected to double to around 88 million Americans over the next 40 years. But there's good news for some in that not all dementia is permanent. NY1's Erin Billups filed the following report.

We're living longer and more adults are reaching ages where the risk of dementia increases. We've all heard of Alzheimer's but there's a less well-known condition - normal pressure hydrocephalus, or NPH.

"Normal pressure hydrocephalus is a hidden epidemic. Latest estimates suggest there's as many as 700,000 Americans with this condition, most of whom have gone undiagnosed," says Dr. Norman Relkin, a behavioral neurologist.

Dr. Norman Relkin recently stepped down as director of Weill Cornell Medicine's Memory Disorder Program to spread the word about NPH symptoms and treatment.

"From the standpoint of all the diseases which cause dementia in the elderly this is one which is very much hidden in the population because the symptoms overlap so much with other conditions that are common among those over 65," says Dr. Relkin.

NPH is an abnormal buildup of spinal fluid in the brain, similar to a condition commonly found in infants.

There are three main symptoms - trouble walking - a sort of glue-footed gait, impaired bladder control and dementia that impacts the ability to perform daily tasks like tying shoes. But it's one of the few dementia-related diseases that is treatable if found within the first two years that symptoms start.

"It's not only treatable, it's reversible, if it's caught in time," Dr. Relkin explains.

Or it could help slow the progression of illness. The treatment is a surgical procedure in which a shunt is placed in the brain and connected to a valve.

"Whenever an excess of fluids develops in the brain the valve opens up and allows that fluid to drain off into the body where it can be cleared out through the blood," Dr. Relkin notes.

New technology using magnets allows surgeons to tailor the right pressure to each patient.

"The best available treatments for Alzheimer's do not stop or reverse the symptoms, whereas in this case effective treatment could mean the difference between someone ending up in a nursing home or ending up bedbound, versus going out and living independently," Dr. Relkin says.

For more information, visit www.hydroassoc.org.