NORMAL PRESSURE HYDROCEPHALUS (NPH)
by Laura Paré, M.D.
Normal Pressure Hydrocephalus, or NPH, is a non-genetic neurological disorder that normally occurs in adults 55-60 years or older. It is often misdiagnosed as Alzheimer's or Parkinson's Disease. NPH is caused by an excess amount of cerebrospinal fluid (CSF) within the spaces of the brain called ventricles. Normally, the amount of CSF that is produced is equal to the amount that is drained out. When the CSF produced is not properly drained, the ventricles can become enlarged, causing a distortion of nearby brain tissue. The enlargement of the ventricles and distortion of the surrounding brain tissue causes three main symptoms of NPH called "the triad." The NPH triad consists of difficulty walking, urinary incontinence, and memory problems. Walking difficulty is characterized by a wide-based, slow, shuffling gate; the feet may seem to be "stuck" to the floor. Urinary incontinence is characterized both by inability to reach the toilet in time and by loss of bladder control. The dementia, or memory difficulties, is characterized by reduced shortterm memory which can progress to difficulties performing normal daily activities.
NPH can be caused by brain injury from trauma, hemorrhage, or infection. For many patients who have no history of infection or brain injury, the cause may be aging of the brain, itself.
NPH can be treated surgically by placing a draining device, or shunt, to drain the excess CSF into the abdomen, where it will be absorbed. This allows the ventricles to return to their normal size and reduces the distortion of the brain tissues. The brain can then function properly and send the correct messages down to other parts of the body, resulting in better control of walking, bladder, and memory.
NPH vs. Alzheimer's or Parkinson's Disease
NPH is often misdiagnosed as Alzheimer's disease or Parkinson's disease. There are some overlap of symptoms in Alzheimer's disease as compared to NPH. Cognitive changes predominate earlier and the gait difficulties occur later in Alzheimer's disease. In Parkinson's disease the symptoms of tremor and rigidity are usually more pronounced, the gait is often narrow-based, and cognitive decline appears late or not at all. NPH can be difficult for physicians to diagnose. If you think that you or a family member may suffer from NPH, it is best to be evaluated by a neurologist, who is familiar with the diagnosis and treatment of NPH, Parkinson's, and Alzheimer's. The neurologist will then refer you or your family member for neurosurgical evaluation, if appropriate.
NPH RESEARCH SUBJECTS NEEDED!
UCI Department of Neurological Surgery is launching a clinical study of normal pressure hydrocephalus (NPH) and is looking for subjects. This syndrome consists of difficulty walking, urinary incontinence, and memory difficulties, in any combination.If you or someone you know might be interested in participating, please call the study coordinator, Ann Ma, NP at (714) 456-6966 for more details.
