Hydrocephalus, also called water in the brain, is a condition where there is an abnormal build up of CSF (cerebrospinal fluid) in the cavities (ventricles) of the brain. The build-up is often caused by an obstruction that prevents proper fluid drainage.
What is hydrocephalus?
CT and MRI scans of the brain may be used to identify and diagnose hydrocephalus.
In hydrocephalus, the build-up of CSF can raise pressure inside the skull, which squashes surrounding brain tissue.
In some cases, this can cause the head to steadily grow in size, convulsions, and brain damage. Hydrocephalus can be fatal if left untreated.
Other symptoms include headaches, vomiting, blurred vision, cognitive problems, and walking difficulties.
The outlook for a patient with hydrocephalus depends mainly on how quickly the condition is diagnosed and treated, and whether there are any underlying disorders.
The term “water in the brain” is incorrect, because the brain is surrounded by CSF (cerebrospinal fluid), not water. CSF has three vital functions, it:
protects the nervous system
nourishes the brain
The brain produces about 1 pint of CSF each day, and old CSF is absorbed into blood vessels. If the process of producing and removing CSF is disturbed, CSF can accumulate, causing hydrocephalus.
There are a number of types of hydrocephalus:
Approximately 1 in every 500 American babies are born with hydrocephalus. It may be caused by an infection in the mother during pregnancy, such as rubella or mumps, or a birth defect, such as spina bifida. It is one of the most common developmental disabilities, more common than Down syndrome or deafness.
This develops after birth, usually after a stroke, brain tumor, meningitis, or as a result of a serious head injury.
This type of hydrocephalus occurs when the CSF becomes blocked after leaving the ventricles. It is called “communicating” because CSF can still flow between the brain’s ventricles.
Also called obstructive hydrocephalus, non-communicating hydrocephalus occurs when the thin connections between the ventricles become blocked.
Normal pressure hydrocephalus
This only affects people aged 50 or older. It may develop after stroke, injury, infection, surgery, or hemorrhage. However, in many cases, doctors do not know why it occurred. An estimated 375,000 older adults in America have normal pressure hydrocephalus.
This type occurs after stroke, traumatic brain injury, or degenerative diseases. As brain tissue shrinks, the ventricles of the brain become larger.
What you need to know about spina bifida
Spina bifida happens when the the spinal column does not close properly. It can lead to hydrocephalus. Find out more.
Hydrocephalus occurs when too much fluid builds up in the brain; specifically, excess CSF (cerebrospinal fluid) accumulates in the cavities (ventricles) of the brain.
There are more than 100 possible causes of hydrocephalus, but the underlying reasons are:
Too much CSF is produced.
One of the ventricles in the brain is blocked or narrowed, stopping or restricting the flow of CSF, so that it cannot leave the brain.
CSF cannot filter into the bloodstream.
Causes of congenital hydrocephalus (present at birth)
The baby is born with a blockage in the cerebral aqueduct, a long passage in the midbrain that connects two large ventricles. This is the most common cause.
The choroid plexus produces too much CSF.
Health conditions in the developing baby can cause problems in how the brain develops. For instance, hydrocephalus is common in children with severe spina bifida (a birth defect of the spinal cord).
Infections during pregnancy – these can affect the development of the baby’s brain. Examples include: