Symptoms of Normal Pressure Hydrocephalus
Normal pressure hydrocephalus (NPH) is typically characterized by a triad of symptoms: gait disturbance or difficulty walking, mild dementia and impaired bladder control. These symptoms may occur individually and at different times and may vary in level of seriousness.
- Mild dementia is described as a loss of interest in daily activities, forgetfulness, difficulty dealing with routine tasks and short-term memory loss. NPH is one of the few treatable forms of dementia.
- Impairment in bladder control in mild cases is typically characterized by urinary frequency and urgency, and in severe cases is a complete loss of bladder control or urinary incontinence. Some people with NPH never display signs of bladder problems.
- Gait disturbances range in severity from mild imbalance to the inability to stand or walk at all. Gait is often widebased, short-stepped, slow and shuffling. Gait disturbance is often the most pronounced symptom and the first to become apparent.
Diagnosing Normal Pressure Hydrocephalus
Gait and balance difficulties typically appear before urinary incontinence and cognitive decline, but patients need not exhibit the complete triad of symptoms before undergoing an evaluation.
When a geriatrician or primary care physician suspects possible NPH, they can help by offering a prompt referral to a neurosurgeon or neurologist. One or more of the following tests is usually performed to confirm the diagnosis and to assess the person’s candidacy for surgical treatment:
- Clinical exams to evaluate symptoms consist of an interview and/or physical/neurological examination.
- Brain images to detect enlarged ventricles commonly include magnetic resonance imaging (MRI) and computerized tomography (CT).
- Cerebrospinal fluid (CSF) tests to predict shunt responsiveness and/or determine shunt pressure include lumbar puncture, external lumbar drainage, measurement of CSF outflow resistance, intracranial pressure (ICP) monitoring and isotopic cisternography.
The process of diagnosing NPH can be challenging. The symptoms of gait disturbance, mild dementia and bladder control problems can also occur with a number of other conditions that affect people over 60. Sometimes these conditions coexist with hydrocephalus, making the diagnosis even more difficult.