Hydrocephalus

Many words used in the English language have Greek origins, such as “micro,” or small, “octo,” which means eight, or “pedi,” which refers to the feet. The term “hydrocephalus” also is derived from Greek, “hydro” meaning water and “cephalus” meaning head. Once called “water on the brain,” hydrocephalus actually is an accumulation of cerebrospinal fluid (CSF) within the brain that can cause brain damage or even death.

The brain is the consistency of gelatin and has four, large open structures called ventricles. CSF flows through and around the ventricles by way of interconnecting passages, and is eventually absorbed into the bloodstream. CSF keeps brain tissue buoyant and acts as a shock absorber, delivers nutrients to the brain and eliminates waste, and compensates for changes in the amount of blood in the brain. Hydrocephalus occurs when the flow of CSF is disrupted or the body does not absorb the fluid properly.

There are two kinds of hydrocephalus, congenital and acquired. Congenital hydrocephalus is present at birth and can cause an unusually large head, vomiting, sleepiness, irritability, seizures, developmental delays, and eyes fixed downward. It may occur due to influences at some stage in fetal development or because of genetic abnormalities. Acquired hydrocephalus affects people of all ages because of injury or disease. Common signs of this type of hydrocephalus include headache, vomiting, nausea, double or blurred vision, lack of energy, coordination problems, memory loss, urinary incontinence, and changes in personality.

Hydrocephalus can be diagnosed in babies before birth during a routine prenatal ultrasound. The condition may be identified in infants and young children when the head is measured as part of regular growth monitoring. Hydrocephalus can be detected in older children and adults if signs and symptoms are present that would indicate the condition. Detailed pictures of the brain can be taken using computerized tomography or magnetic resonance imaging.

Surgery is the accepted treatment for hydrocephalus. The procedure usually involves placing a shunt system to divert CSF from the brain to another area of the body where it can be more easily absorbed, such as the abdomen or chamber of the heart. A shunt system consists of a catheter, which is placed within a ventricle inside the brain or in the CSF outside the spinal cord, a shunt, which is a long flexible tube, and a valve that keeps fluid flowing in the right direction and at a regulated rate.

As a child grows, additional surgeries may be necessary to insert longer tubes. The shunt also may need to be replaced if an infection develops or tubing becomes blocked. Shunt systems require ongoing medical follow-up. Another less frequently performed surgery to treat hydrocephalus involves making a hole in the bottom of one of the ventricles to allow CSF to flow to the base of the brain where it can be absorbed.

The outlook for patients with hydrocephalus depends on the cause of the condition, presence of other complications, timeliness of diagnosis, and success of treatment.