Hydrocephalus is an abnormal build up of cerebrospinal fluid (CSF) within the ventricles of the brain.
CSF is produced in a continuous fashion, flows through the ventricles and surrounds the brain and spinal cord. When there is a build-up of CSF, the pressure inside the head increases and this leads to symptoms.Hydrocephalus can occur in both infants and adults. The signs and symptoms vary by age.
- Vomiting, sleepiness, irritability, poor feeding
- Unusually large head, increase in head size
- Poor growth
- Impaired vision
- Decline in memory and concentration
In addition to the above,
- Loss of bladder control
- Memory loss
- Abnormal gait (shuffling or feeling of feet being stuck)
- Poor balance
As the symptoms of hydrocephalus can be varied and can progress rapidly, it is important to seek prompt medical attention.
The build-up of CSF most commonly occurs due to obstruction of the flow of the CSF. Other causes are due to poor absorption or over-production of CSF.
An important cause of hydrocephalus in the elderly (in their 60-70’s) is Normal Pressure Hydrocephalus.
Normal Pressure Hydrocephalus (NPH)
- Cause of hydrocephalus in the elderly
- Often misdiagnosed as Alzheimer or Parkinson disease as NPH patients also have symptoms of dementia
- Some statistics show that fewer than 20% of people with NPH are diagnosed
- The three hallmark symptoms of NPH are:
- Walking problem
- Difficulty with memory (dementia)
- Loss of bladder control
- NPH is one of the few causes of dementia that can be controlled or reversed with treatment.
Hydrocephalus is diagnosed with a combination of:
- Neurological history and examination
- Brain imaging
- CT scans
- MRI scan
- Cerebrospinal fluid tests (sometimes required)
- Lumbar puncture, external lumbar drainage, CSF outflow resistance, intracranial pressure monitoring
There are two main treatment methods both of which relies on redirecting the flow of cerebrospinal fluid.
A device called a shunt is inserted. It consists of a long, flexible tube with a valve that keeps fluid from the brain flowing in the right direction. The shunt is placed such that the fluid is directed from the brain into another part of the body where it can be absorbed (e.g. in the abdomen).
There are different types of valves:
- Programmable valves (in these, the valve pressure settings can be adjusted).
- Non programmable valves (fixed pressure)
There are also different places where the shunt can be placed. Common ones include:
- Ventriculoperitoneal - brain ventricle to abdomen (most common in Singapore)
- Ventriculoatrial - brain ventricle to heart chamber
- Ventriculopleural - brain ventricle to chest
- Lumboperitoneal - lumbar spinal canal to abdomen
Endoscopic third ventriculostomy
Endoscopic third ventriculostomy is an alternative to shunt implantation. This can be an option for some patients where the cause of the hydrocephalus is due to obstruction. A small hole is placed using an endoscope at the bottom of the third ventricle to bypass the usual flow of CSF. The main difference is that there is no requirement for a permanent implant and the operation can be performed through one incision.
- Hydrocephalus can present with both acute and delayed symptoms.
- The causes vary according to the age of the person.
- Prompt medical attention is often required.