Normal Pressure Hydrocephalus
Normal Pressure Hydrocephalus results from the gradual blockage of the CSF draining pathways in the brain. The ventricles enlarge to handle the increased volume of CSF, thus compressing the brain from within and eventually damaging or destroying the brain tissue. NPH owes its name to the fact that the ventricles inside the brain become enlarged with little or no increase in pressure. However, the name can be misleading, as some patients' CSF pressure does fluctuate from high to normal to low when monitored.
NPH can occur as the result of head injury, cranial surgery, hemorrhage, meningitis or tumor. Unfortunately, the cause of the majority of NPH cases is unknown, making it difficult to diagnose and understand. Compounding this difficulty is the fact that some of the symptoms of NPH are similar to the effects of the aging process, as well as diseases such as Alzheimer's and Parkinson’s. The majority of the NPH population is older than 60, and many of these people believe their symptoms are just part of the aging process. Unfortunately, many cases go unrecognized, are never properly treated or are misdiagnosed.
- Primary symptoms of Normal Pressure Hydrocephalus (NPH)
- Gait disturbances/imbalance
- Memory problems or dementia
- Bladder control symptoms.
Ventriculo-peritoneal shunt: implanting a device known as a shunt to divert the excess CSF away from the brain. The body cavity in which the CSF is diverted is usually the peritoneal cavity (the area surrounding the abdominal organs). The surgeon makes a hole in the skull and another small surgical cut is made in the belly. A small hole is drilled in the skull. A small thin tube called a catheter is passed into a ventricle of the brain. This can be done with or without a computer as a guide. It can also be done with an endoscope that allows to see inside the ventricle. Another catheter is placed under the skin behind the ear and moved down the neck and chest, and usually into the belly area. Sometimes, it stops at the chest area. The doctor may make a small cut in the neck to help position it. A valve (fluid pump) is placed underneath the skin behind the ear. The valve is connected to both catheters. When extra pressure builds up around the brain, the valve opens, and excess fluid drains out of it into the belly or chest area. This helps decrease intracranial pressure. The valves can be programmed to drain more or less fluid from the brain.
An alternative operation called endoscopic third ventriculostomy utilizes a tiny camera to look inside the ventricles, allowing the surgeon to create a new pathway through which CSF can flow.