Hydrocephalus

Your brain is the consistency of gelatin, and it floats in a bath of cerebrospinal fluid. This fluid also fills large open structures, called ventricles, which lie deep inside your brain. The fluid-filled ventricles help keep the brain buoyant and cushioned.

Cerebrospinal fluid flows through the ventricles by way of interconnecting channels. The fluid eventually flows into closed spaces between the brain and skull, where it's absorbed into your bloodstream.

Keeping the production, flow and absorption of cerebrospinal fluid in balance is important to maintaining normal pressure inside your skull. Hydrocephalus results when the flow of cerebrospinal fluid is disrupted — for example, when a channel between ventricles becomes narrowed — or when your body doesn't properly absorb this fluid.

Defective absorption of cerebrospinal fluid causes normal pressure hydrocephalus, seen most often in older people. In normal pressure hydrocephalus, excess fluid enlarges the ventricles but does not increase pressure on the brain. Normal pressure hydrocephalus may be the result of injury or illness, but in most cases the cause is unknown.

The signs and symptoms of hydrocephalus vary by age group and disease progression. In infants, common signs and symptoms of hydrocephalus include:

• An unusually large head
• A rapid increase in the size of the head
• A bulging "soft spot" on the top of the head
• Vomiting
• Sleepiness
• Irritability
• Seizures
• Eyes fixed downward (sunsetting of the eyes)
• Developmental delay

In older children and adults, common signs and symptoms of hydrocephalus include:

• Headache followed by vomiting
• Nausea
• Blurred or double vision
• Eyes fixed downward (sunsetting of the eyes)
• Problems with balance, coordination or gait
• Sluggishness or lack of energy
• Slowing or regression of development
• Memory loss
• Confusion
• Urinary incontinence
• Irritability
• Changes in personality