About Hydrocephalus


From the Greek words “hydro” (water) and “cephalus” (head), hydrocephalus is often referred to as ‘water on the brain.’


Rather than water, however, it is the accumulation of cerebrospinal fluid (CSF) that characterizes hydrocephalus.


Hydrocephalus in Children and Adults

This condition is the most common congenital defect of the brain and spine with 1 in 500 infants born with this condition. Although hydrocephalus can occur in adults, it is more common in children, especially infants, and causes potential damage to the brain.


At ANA, we treat numerous pediatric and adult patients for hydrocephalus. Hydrocephalus may be congenital or acquired.


Congenital hydrocephalus is present at birth and possibly acquired during fetal development or due to genetic abnormalities.


Acquired hydrocephalus occurs at, or some time following, birth. This type of hydrocephalus, which may be caused by injury or disease, can affect individuals of all ages.


Is Hydrocephalus Rare?

Approximately 1 million Americans have hydrocephalus, making it a relatively rare condition. However, with around one in 770 babies born with hydrocephalus, it is similar to down syndrome and more common than getting a brain tumor or spina bifida.


What Is Hydrocephalus?

At about 6 weeks in utero, the fetus beings to produce cerebrospinal fluid (CSF), a clear liquid surrounding the brain and spinal cord. Normally, this fluid bathes the ventricular system of the brain— the brain includes four ventricles (cavities) connected by narrow pathways — and is then absorbed into the bloodstream.


Hydrocephalus is usually caused by either an obstruction or overproduction of CSF leading to its accumulation and increased intracranial pressure.


There are two other forms of hydrocephalus, which primarily affect adults and do not fit exactly into the categories mentioned above: hydrocephalus ex-vacuo and normal pressure hydrocephalus (NPH).


Hydrocephalus ex-vacuo follows a stroke or traumatic injury that causes brain damage. In these cases, brain tissue may actually shrink.


NPH, which affects an estimated 375,000 older adults, is an abnormal increase of cerebrospinal fluid in the brain’s ventricles that may result from a subarachnoid hemorrhage, head trauma, infection, tumor, or complications of surgery. However, many people develop NPH when none of these factors are present.


The root causes of hydrocephalus are not completely clear. According to the National Institutes of Health (NIH), there are over 180 possible causes of hydrocephalus.


While it may result from genetic inheritance or developmental disorders, such as those associated with neural tube defects including spina bifida and encephalocele, other possible causes include:

  • complications of premature birth;
  • diseases such as meningitis, tumors, traumatic head injury, and obesity;
  • subarachnoid hemorrhage causing a blockage of fluid.


Hydrocephalus may also be described as ‘communicating’ or ‘non-communicating.’ Communicating hydrocephalus occurs when the flow of CSF is blocked after it exits the ventricles. This form is called communicating because the CSF can still flow between the ventricles, which remain open.


Non-communicating hydrocephalus, also called “obstructive” hydrocephalus, occurs when the flow of CSF is blocked along one or more of the narrow passages connecting the ventricles.


Can Hydrocephalus Be Cured?

While there is no cure for this condition, it is treatable. In 25 years, death rates decreased from 54% to 5%.


ANA is committed to the most comprehensive care for those who come to us from among the 1 million Americans who suffer from this disease.


To learn more about how our caring and dedicated neurosurgeons can help you and your loved one, please call us today. Serving New Jersey, New York, Connecticut and Pennsylvania, Advanced Neurosurgery Associates’ team is ready to help anytime.