Craniosynostosis is a term that refers to the early closing of one or more of the sutures of an infant’s head. The skull is normally composed of bones which are separated by sutures. As an infant’s brain grows, open sutures allow the skull to expand and develop a relatively normal head shape. If one or more of the sutures has closed early, it causes the skull to expand in the direction of the open sutures. This can result in an abnormal head shape. In severe cases, this condition can also cause increased pressure on the growing brain.