PRAIRIE GROVE – During a visit to Rush University Medical Center in Chicago, Katie Cook, who was five months pregnant at the time, heard the unsettling news that her first child-to-be had hydrocephalus.

The potentially life-threatening disease, commonly referred to as “water on the brain,” is the abnormal collection of cerebral fluid in the brain that can stunt development. It affects one in every 500 children, according to the National Institute of Neurological Disorders and Stroke.

Cook’s visit with doctors at Rush was three years ago. She was devastated by the news, but she now regards her son, Conor, as a bright, energetic boy who is doing well despite his condition. The 3-year-old had a shunt placed on the right side of his brain two months after his birth. It drains the fluid through a valve that stretches down his neck and into his abdomen. The shunt is the mainstay treatment for hydrocephalus.