Craniosynostosis is a congenital (present from before birth) defect, characterized by premature closure of one or more sutures (connections between plates in the skull), which causes an abnormally shaped skull.

The cause of craniosynostosis is unknown. In an infant's head, the sutures mark the boundaries between the bony plates that make up the skull. Premature closure of these sutures stops bony growth and results in deformity of the skull. The shape of the deformity is determined by which sutures are involved.

The condition may be hereditary and caused by a genetic defect, or it can occur sporadically in a family with no other affected relatives. The hereditary form often occurs in conjunction with other defects, which can cause seizures, diminished intellectual capacity, and blindness.

• Absence of the normal feeling of a "soft spot" (fontanelle) on the newborn's skull
• Disappearance of the fontanelle early
• A raised hard ridge along the affected sutures
• Unusual head shape
• Slow or no increase in the head size over time as the baby grows

A neurologic exam would help diagnose the condition, including:

• measurement of the infant's head circumference
• doctor palpating (feeling) the skull
• X-rays of the skull and/or a CT scan of the head

The main treatment for craniosynostosis is surgery during infancy. The surgical goal is to relieve intracranial pressure, assure that the skull has the capacity to accommodate the brain's growth, and cosmetically improve the appearance of the child's head.

In the sporadic from of craniosynostosis, the post-surgical results are generally good. Craniosynostosis associated with inherited syndromes usually has less optimal outcomes, because these syndromes are also associated with seizures, developmental delay, and blindness.

Overall, the prognosis for craniosynostosis varies depending on whether single or multiple skull sutures are involved and the presence of other associated abnormalities. The prognosis is better for those with a single suture involved and no other abnormalities.

Untreated craniosynostosis results in deformity of the head that can be severe and, if uncorrected, permanent. Raised intracranial pressure, seizures and developmental delay can occur.

Call your health care provider if you think your child's head has an unusual shape. A referral to a pediatric neurologist or neurosurgeon should follow.

Genetic counseling for people with hereditary (familial) craniosynostosis may help prevent some cases. Also, your pediatrician should routinely chart the growth of your infant's head over time to recognize the problem early if it occurs.