Types of hydrocephalus

All types of hydrocephalus involve the buildup of cerebrospinal fluid (CSF) within the brain. As this fluid accumulates, it increases pressure within the brain, which can cause brain damage and permanent loss of physical and mental abilities. But with treatment, many people with hydrocephalus have few, if any, long-term effects.

Cerebrospinal fluid sometimes builds up rapidly, such as with an injury, and can cause sudden and severe damage if not treated. Other times the fluid gradually accumulates and may not cause problems right away.

Types of hydrocephalus include:

• Congenital hydrocephalus , which is present at birth. Congenital hydrocephalus may be caused by physical problems with how CSF flows or is made or absorbed, by infections or trauma during fetal development, or by teratogens. It may be associated with other birth defects that affect the spine, especially open neural tube defects.
• Acquired hydrocephalus, which develops at the time of birth or later. It can be caused by infections such as meningitis, bleeding, injury, or a tumor.
• Normal-pressure hydrocephalus, which usually develops in people who are age 55 or older. It is a potentially treatable cause of dementia. This type of hydrochephalus often occurs after head trauma, infections, and bleeding within the brain.
• Ex-vacuo hydrocephalus, which occurs when there is damage to the brain caused by stroke or traumatic injury. This type of hydrocephalus may not be a health danger for some people, in which case treatment is not needed.

With all types of hydrocephalus, early detection and treatment are important to minimize or prevent long-term problems.