Normal pressure hydrocephalus (NPH) is a condition that is caused by an abnormal build up of cerebrospinal fluid (CSF) in the ventricles (cavities or spaces) of the brain. Cerebrospinal fluid is a clear liquid that circulates around the brain and spinal cord, cushioning and protecting them from damage. When people have NPH, they have an excess of cerebrospinal fluid because their bodies cannot properly drain and absorb the fluid. This fluid build-up can harm the brain.
The differences between NPH and other forms of hydrocephalus is that even though there is a larger than normal amount of CSF, the pressure inside the ventricles remains the same. This buildup of fluid causes symptoms to occur over time.
Normal pressure hydrocephalus most often occurs in people over age 60.
It is difficult to know how many people actually have normal pressure hydrocephalus (NPH) because its symptoms are similar to other diseases, such as Alzheimer's or Parkinson's disease, or even the natural aging process itself. However, it is estimated that as many as 10 percent of people with dementia attributed to other disorders may actually have NPH.
The exact cause of normal pressure hydrocephalus (NPH) is not clear. In most cases of NPH, the cause of the buildup of cerebrospinal fluid (CSF) is unknown. However, in some cases, NPH can occur as a result of other conditions that affect the brain including:
There are three classic symptoms of normal pressure hydrocephalus (NPH):
Diagnosis begins with a careful review of symptoms and medical history. medical interview and a physical exam. Other tests include:
Although there is no cure for NPH, the symptoms can be managed through surgery. Surgery involves inserting a drainage system called a shunt. One end of the shunt -- which is a long sturdy, flexible plastic tube -- is placed into one of the brain's ventricles. The other end is tunneled under the skin to another area of the body, usually the lower part of the abdomen.
The shunt allows the excess cerebrospinal fluid to drain from the brain and be absorbed back into the body. A valve in the shunt keep the fluid flowing in the correct direction and at the right rate. The shunt remains in the person's body for the rest of his or her life.
Complications of normal pressure hydrocephalus (NPH) treatment are those associated with any surgical procedure. They include bleeding, infection, and reaction to the anesthesia used during surgery. Patients might also experience mild abdominal pain. Seizures also may occur as surgery on the brain can affect very sensitive areas of the brain. Fortunately, these complications are not common, and in most cases can be successfully treated.
Right now, there is no known way to prevent NPH. However, getting treatment as soon as symptoms appear can improve those symptoms and increase the chance for a full or partial recovery.
The chance of a good recovery from NPH is more likely if a patient is diagnosed and treated in the early stages. Some people do not need shunt surgery because the symptoms are not severe enough to affect daily life. People who do not need surgery should continue to have check-ups with a doctor to monitor the symptoms. If the symptoms worsen, the doctor may recommend the surgery. Those who get surgery, often find that their symptoms are manageable.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or healthcare provider. Please consult your healthcare provider for advice about a specific medical condition. This document was last reviewed on: 08/27/2018