Normal Pressure Hydrocephalus (NPH)
The term hydrocephalus is derived from the Greek words "hydro" meaning water and "cephalous" meaning the head. Hydrocephalus is a condition in which excess cerebrospinal fluid (CSF) builds up within the fluid-containing cavities (ventricles) of the brain.
CSF is in constant circulation within the ventricles of the brain and flows between the cranium and spine to regulate changes in pressure.
Normal Pressure Hydrocephalus: It is a form of hydrocephalus that can occur at any age, but is most common in the elderly. It is characterized by dilated ventricles with normal pressure within the spinal column.
Symptoms of Normal Pressure Hydrocephalus (NPH)
Difficulty walking (ataxia) / loss of balance while walking.
Loss of urinary control (incontinence).
Memory loss / Impaired cognitive skills
Diagnosis of NPH
A complete neurological examination by a neurosurgeon / neurologist followed by one of more of the following tests:
CT of the brain
MRI of the brain
Lumbar puncture (spinal tap) to examine CSF, measure its pressure and to see the effect of CSF drainage on the symptoms. If symptoms improve after CSF drainage, then a diagnosis of NPH is made.
If symptoms improve following CSF drainage (via lumbar puncture) then some type of CSF drainage surgery is offered i.e. VP shunt with programmable valve or lumbo-peritoneal shunt.
In Ventriculo-Peritoneal (VP) shunt surgery, a flexible tube is placed into the ventricle of the brain and other into the abdominal (peritoneal) cavity. Both these tubes are connected to a valve, which ideally is programmable to control the pressure at which CSF is drained.
In Lumbo-Peritoneal (LP) shunt one end of the tube is placed in the lumbar part of the spine and the other end goes into the abdominal (peritoneal) cavity. This drains CSF from the lumbar part of the spine and helps in reducing CSF pressure.
A 70-year-old gentleman, presented with a one-year history of ataxia of gait, memory impairment and urinary incontinence.
After reviewing the MRI a trial of CSF drainage through a lumbar puncture was performed. He responded quite well to this drainage and his walking improved significantly.
He was then offered VP shunt using a programmable valve. The pressure was adjusted after surgery so that both over drainage (causing brain hemorrhage) or under drainage (causing nonfunctional shunt) could be avoided.
One month later he showed a dramatic improvement of all his symptoms. He now goes for long walks with significant improvement in quality of life (QOL).