Hydrocephalus is a condition in which there is an abnormal accumulation of cerebrospinal fluid (CSF) within the brain. The term hydrocephalus comes from the Greek words “hydro” meaning water and “cephalus” meaning head. The condition causes increased pressure inside the skull and was once known as “water on the brain.” Hydrocephalus may be acquired or congenital.
Congenital hydrocephalus is present at birth and may be caused by physical problems with how cerebrospinal fluid flows or is absorbed or made, by trauma during fetal development, or teratogens (agents that cause malformation of an embryo). Acquired hydrocephalus may develop at the time of birth or later and can be caused by infections like meningitis, injury, bleeding, or a tumor.
Hydrocephalus ex-vacuo and Normal Pressure Hydrocephalus (NPH) are two additional forms of hydrocephalus that affect mostly adults. Hydrocephalus ex-vacuo occurs when there is damage to the brain caused by traumatic injury or stroke. Normal Pressure Hydrocephalus (NPH) occurs after head trauma, infections, and bleeding within the brain and occurs in people who are 55 years of age and older.
Older people may experience double vision, headaches, poor balance, changes in personality, urinary incontinence, or mental impairment.
Other symptoms may include seizures, vomiting, sleepiness, and downward pointing of the eyes. Babies with hydrocephalus may experience a rapid increase in head size. Symptoms can vary greatly from person to person.
Hydrocephalus results from an imbalance of cerebrospinal fluid in the body. Produced by ventricles lining the brain, cerebrospinal fluid is vital to maintaining the brain. It provides the organ with its buoyancy, cushions the brain against possible injury, removes waste, and helps to maintain the brain’s need for consistent pressure.
When there’s an excess of this fluid and hydrocephalus occurs, it’s largely due to one of three reasons. Most commonly, an obstruction has been created and is interfering with the flow of cerebrospinal fluid. The obstruction can occur between two ventricles or between one ventricle and the spaces in the brain. A second possibility, though less common, has to do with the sudden inability of blood vessels to absorb cerebral spinal fluid. When this happens, it’s most often due to the swelling of the brain, due to illness or injury. Finally, there’s the rare alternative of an overproduction of cerebral spinal fluid. This occurs when the ventricles produce cerebrospinal fluid faster than it can be used by the brain.
Successful treatment involves placing a shunt (drainage tube) between the brain ventricles and abdominal cavity. The shunt system diverts the flow of cerebrospinal fluid from the central nervous system to another part of the body where it can be absorbed as part of the normal circulatory system.
Hydrocephalus isn’t preventable, but there are ways to reduce one’s risk of contracting the condition. Reducing the risks begins with pregnant women and their diligence in adhering to prenatal care. By lowering the possibility of a premature delivery, pregnant women can also ensure that their children are less likely to develop hydrocephalus.
Vaccinations against infection and other illnesses can go a long way toward protecting an unborn baby against hydrocephalus. One important vaccination for this purpose is the vaccine against meningitis, as this condition is a direct cause of hydrocephalus. Mothers should speak with their doctors about protecting their children against risk factors of hydrocephalus. These include immune system deficiencies, a damaged spleen (or the procedure for having it removed), and traveling to areas where meningitis is more prevalent.