Craniosynostosis syndromes

What are craniosynostosis syndromes?

In craniosynostosis syndromes, one or more bones of the skull and face fuse prematurely during fetal development. The skull is made up of multiple bones separated by bands of soft tissue called sutures. The sutures allow the skull to grow as the brain develops. If any of these close too early, the skull will expand in the direction of the remaining open sutures, resulting in an abnormal head shape. These syndromes are caused by rare genetic mutations.

Premature closure of a single suture can be caused by space constraints in the womb and is seen more often in twins than in a single fetus. Single suture closure usually isn't associated with a syndrome. Children with craniosynostosis syndrome experience premature closure of multiple sutures as well as other health issues or syndromes.

Types of craniosynostosis syndromes

In a child with a craniosynostosis syndrome, the bones in the skull fuse too early, causing an abnormal head shape. Bones in the face may also fuse together, resulting in a flat midface and bulging eyes. The skull anomalies can affect eating and breathing and may also be associated with other developmental problems.

There are several different types of craniosynostosis syndromes. These are the most common:

• Pfeiffer syndrome. This affects about one of every 100,000 births, and the severity of its observable characteristics varies. Children with this type usually develop large thumbs or big toes, and in some cases, webbed fingers or toes. Some children may also experience neurological development issues.
• Crouzon syndrome. This occurs in about one of every 100,000 births. The severity of symptoms can also vary considerably, from no visible physical effects to webbed fingers and toes. Neurological development issues are rare but can occur in some cases.
• Apert syndrome. This affects about one of every 65,000 births and varies less from case to case than Crouzon and Pfeiffer. Children with this syndrome also have syndactyly, or webbing, of the hands and feet.

In most cases, children with these syndromes have premature fusion of at least the opening that extends across the top of the skull. But, they may also have early closure of sutures in other parts of the skull and face.

Diagnosis of craniosynostosis syndromes

Craniosynostosis syndromes are diagnosed through physical examination at birth. Tests such as CT scans and X-rays may be used to confirm the diagnosis, as well as testing for the genetic mutations that have been linked to the syndromes.

Treatment of craniosynostosis syndromes

An infant with a craniosynostosis syndrome should be checked right after birth by a nurse from the Pediatric Craniofacial Center to make sure there's no difficulty breathing or eating. Shortly after leaving the hospital, the child should be seen for a full evaluation by the team at the center. These types of skull abnormalities require early attention, although the timing of treatments varies.

Surgery and dental restoration for craniosynostosis syndromes

A baby with a craniosynostosis syndrome may require multiple surgeries to correct their skull and facial anomalies.

A surgical procedure to adjust the positioning of the bones of the forehead is usually done before the baby is 6 months old.

If the facial bones are fused, a child may need midface advancement surgery. This is a procedure that brings the cheekbones and upper jaw forward to better protect the eyes and improve the child's airway. Because the upper jaw is usually too small, a child with a craniosynostosis syndrome can have an underbite and severely crowded teeth. These are usually corrected with braces, as well as surgical procedures. Timing for the midface advancement and orthodontics is based on a number of factors. They may be done early in life or after growth is completed, depending on the particular needs of the child.

In addition, a child who also has syndactyly, or webbing, of the hands and feet usually requires early surgery to improve their mobility and function.

Evaluation of other craniosynostosis syndrome symptoms

There are several health issues often associated with craniosynostosis syndromes. Therefore, it's important that your child also be evaluated by the following specialists:

• A pediatric pulmonologist, or lung specialist, to address any breathing difficulties the child may have
• An ophthalmologist, or eye specialist for vision issues, especially if the child's eyelids don't adequately protect their eyes
• An audiologist and a speech pathologist to make sure the child's speech and language development are on track

A child with a craniosynostosis syndrome may encounter social and emotional challenges unique to these syndromes. Ask your child's doctor about available support organizations and resources.