<p>Hydrocephalus is the buildup of too much cerebrospinal fluid in the brain. Normally, this fluid cushions your brain. When you have too much, though, it puts harmful pressure on your brain.</p> <p>Hydrocephalus can be congenital, or present at birth. Causes include genetic problems and problems with how the fetus develops. An unusually large head is the main sign of congenital hydrocephalus.</p> <p>Hydrocephalus can also happen after birth. This is called acquired hydrocephalus. It can occur at any age. Causes can include head injuries, strokes, infections, tumors, and bleeding in the brain. Symptoms include:</p><ul> <li>Headache</li> <li>Vomiting and nausea</li> <li>Blurry vision</li> <li>Balance problems</li> <li>Bladder control problems</li> <li>Thinking and memory problems</li> </ul> <p>Hydrocephalus can permanently damage the brain, causing problems with physical and mental development. If untreated, it is usually fatal. With treatment, many people lead normal lives with few limitations. Treatment usually involves surgery to insert a shunt. A shunt is a flexible but sturdy plastic tube. The shunt moves the cerebrospinal fluid to another area of the body where it can be absorbed. Medicine and rehabilitation therapy can also help.</p> <p class="">NIH: National Institute of Neurological Disorders and Stroke</p>