Approximately 16 oz. of cerebrospinal fluid (CSF) is formed every day in a normal, healthy brain. This clear liquid circulates in the brain and the spinal cord before it is absorbed. Hydrocephalus is a condition in which excess amount of CSF builds up in the brain. Normal pressure hydrocephalus (NPH) refers to a condition that, according to the National Institute of Health (NIH), is most common among people over the age of 60. NPH patients tend not to have high pressure inside the head. This is unusual for most hydrocephalus forms. NPH typically occurs after a stroke, meningitis, head injury or brain tumor. It is characterized by subtle symptoms that worsen very slowly.
Walking Difficulties
NPH's first symptoms are typically related to walking. These may range from mild walking difficulties to the inability to stand. A patient may have difficulties taking first steps, and he may often report that his legs feel heavy. He may seem "frozen" or stuck to the ground when he tries to walk, just like people suffering from Parkinson's disease. His legs may feel weak, he may fall suddenly and his steps may appear very small and unsteady. Oftentimes, individuals suffering from NPH have difficulty walking up stairs, or even in descending them.
Impaired Bladder Control
The second symptom of NPH is typically related to urinary incontinence. Patients may need to urinate more frequently than usual or they feel a sudden, urgent need to urinate. In more severe cases, patients cannot control their bladder at all. Less frequently, patients cannot control their stool. Some patients do not have any bladder control difficulties.
Cognitive Impairments
Symptoms of mild dementia, such as memory problems, forgetfulness and difficulties focusing, are commonly reported in patients suffering from NPH. These patients may also have problems in reasoning or judgment. Many of these symptoms are easily overlooked and sometimes look like they are a part of normal aging. Occasionally, when a patient experiences more severe cognitive impairment symptoms, his loved ones mistake them for Alzheimer's disease. It is possible for patients to remain completely unaware of their degrading cognitive abilities.
Changes in Behavior or Mood
Patients suffering form NPH sometimes feel like they have lost interest in activities that they used to enjoy, just as if they were suffering from depression. They may also experience mood swings, apathy and withdrawal.
Symptoms Related to Increased Pressure in the Brain
The pressure in the brains of NPH patients is not as high as in other forms of hydrocephalus. Thus, the patients do not usually experience symptoms that are related to pressure. Nevertheless, it is possible for NPH patients to experience such pressure-related symptoms as nausea and vomiting, headaches and a declining level of consciousness.
References
- National Institute for Health: Hydrocephalus Fact Sheet
- Hydrocephalus Association: About Normal Pressure Hydrocephalus
- "Hydrocephalus: Pathogenesis and Treatment"; Matsumoto; 1991.
