The cause of craniosynostosis is for the most part unknown. Craniosynostosis can also occur with some inherited disorders.

In a normal infant's head, the sutures mark the boundaries between the bony plates that make up the skull. Premature closure of sutures stops bony growth and results in deformity of the skull. The shape of the deformity is determined by which sutures are involved. If the sagittal suture (the suture running from the front to back of the head) closes, the head develops a long, narrow appearance. If one of the coronal sutures (running across the top of the head roughly from ear to ear) closes, it results in severe deformity of the head and may affect the appearance of the face and cause visual abnormalities.

Closure of the sagittal suture is more common in boys. Closure of the coronal suture is often associated with genetic syndromes.

• Absence of the normal feeling of a "soft spot" (fontanelle) on the newborn's skull
• A raised hard ridge along the affected suture
• Unusual head shape
• Slow or no increase in the head size (small occipital-frontal circumference)

Skull X-rayfilms or a CT scan of the head with bone windows diagnose the condition.

It is important that this condition be evaluated and diagnosed early so as to achieve the best possible cosmetic result. Surgery to open the sutures has been very successful in preventing the deformities of premature closure.

In the idiopathic form of craniosynostosis, the post-surgical results are generally good. Craniosynostosis associated with inheritable syndromes have less optimal outcomes.

Untreated craniosynostosis results in deformity of the head that can be severe and, if uncorrected, permanent.

Call your health care provider if you think your child's head has an unusual shape.

A family history may provide information about syndromes associated with craniosynostosis. There is no prevention for idiopathic premature closure of the sutures.