Hydrocephalus (pronounced “hi-droh-SEF-eh-less”) is a condition that makes extra spinal fluid build up in the hollow areas around the brain, causing pressure and swelling in the head. Often called “water on the brain,” hydrocephalus can be congenital (present at birth) or acquired (occur over time). It can happen to a child at any age, even a fetus growing in the womb. Although the cause isn’t always known, it usually happens due to a medical problem so it’s important to diagnose it as soon as possible. At Nemours, our goal is to treat the urgent symptoms, and find the reason for the hydrocephalus. Then we work together to make a plan for your child’s long-term health and development.