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Expert’s Corner: Mark Johnson studies a treatable brain disorder that often goes undiagnosed

Mark D. Johnson, MD, PhD, chair and professor of neurosurgery, studies normal pressure hydrocephalus (NPH), and is focused on developing a simple, readily accessible test to identify patients who have it.

Normal pressure hydrocephalus is a brain disorder that has symptoms similar to other neurological conditions, including Alzheimer’s disease and Parkinson’s disease. It involves an abnormal buildup of cerebrospinal fluid in the brain that results in pressure on the brain. Similar to Parkinson’s and Alzheimer’s, NPH causes symptoms such as gait or walking problems, dementia-like behavior and urinary incontinence.

“Approximately 90 percent of the 750,000 Americans living with NPH are misdiagnosed or undiagnosed,” Dr. Johnson said.

NPH is diagnosed through clinical neurological evaluation, neuro-imaging technology such as a CT scan or MRI of the brain, and the response to cerebrospinal fluid pressure (CFS) drainage. Unlike Parkinson’s and Alzheimer’s, many patients are unaware that NPH is treatable, Johnson said.

Learn more about the condition and Johnson’s research in this Expert’s Corner video.