Craniosynostosis Syndromes

In craniosynostosis syndromes, one or more bones of the skull and face fuse prematurely during fetal development. The skull is composed of multiple bones separated by sutures, or openings. If any of these close too early, the skull will expand in the direction of the open sutures, resulting in an abnormal head shape.

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. Premature closure of multiple sutures, however, is often seen in children with a craniosynostosis syndrome.

In children with a craniosynostosis syndrome, bones that fuse prematurely in the skull result in abnormal head shapes. Bones in the face may also be fused together, resulting in a flat midface and protruding eyes.

The most common craniosynostosis syndromes are Crouzon, Pfeiffer and Apert.

  • Pfeiffer syndrome is the most common of the three, affecting about one of every 25,000 births, and its severity varies.
  • Crouzon syndrome occurs in about one of every 100,000 births, and also varies considerably in severity.
  • Apert syndrome affects about one of every 100,000 births and varies less from case to case than Crouson and Pfeiffer. Children with this syndrome also have syndactyly, or webbing, of the hands and feet.

Children with Apert, Crouzon and Pfeiffer syndrome usually have premature fusion of at least the coronal suture, an opening that extends across the top of the skull. Other sutures may also close.

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Both single suture craniosynostosis and 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 genetic testing for mutations of one of the fibroblast growth factor receptor (FGFR) genes.

A baby with single suture synostosis that's not part of a syndrome usually doesn't have any functional problems, such as difficulty breathing or feeding. Surgical release of the closed suture may be necessary, and if so, would usually be done during the first year of life.

An infant with a craniosynostosis syndrome should be seen immediately after birth by a nurse from the Center for Craniofacial Anomalies to make sure the infant can adequately breathe and feed. Shortly after being discharged from the hospital, the child should be seen for a full team evaluation at the center. The skull abnormalities require early attention, although the timing varies. A surgical procedure to advance the forehead is usually done before the baby is 6 months old.

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Reviewed by health care specialists at UCSF Benioff Children's Hospital.

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Craniofacial Center
1825 Fourth St., Fifth Floor, 5C
San Francisco, CA 94158
Phone: (415) 476-2271
Fax: (415) 476-9513
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