Crouzon Syndrome

Overview

Crouzon syndrome is a rare genetic condition affecting the skull and facial bones. It leads to craniosynostosis, and underdevelopment of the facial bones. Crouzon syndrome occurs somewhere between one in 50,000 and one in 100,000 births. 

Cause of Crouzon syndrome

Crouzon syndrome has two variants caused by gene mutations. Both of these mutations arise randomly and sporadically. We don’t fully understand what causes this mutation. However, it doesn’t appear that the mutation occurs as a result of something either parent does or fails to do. Most parents who have a baby with Crouzon syndrome have normal genes.  

Children with Crouzon syndrome can pass the gene on to their children. Only one copy of the gene needs to be passed on for the new baby to have Crouzon syndrome.  A parent with Crouzon syndrome has a 50-50 chance of having a baby who also has Crouzon syndrome. Anyone with Crouzon syndrome who wishes to have children should consider meeting with a geneticist to discuss the risks and make a thoughtful, informed decision. 

Characteristic traits

The skull is made of a number of bone plates, joined together at specialized joints called sutures. These sutures act like expansion joints, allowing the skull to get larger as your child grows and his developing brain pushes outward. In Crouzon syndrome, two of these sutures fuse prematurely, preventing the forehead from growing forward.  Since the brain cannot push the forehead forward as it grows, the brain instead pushes outward and upward in other parts of the skull where these expansion joints are functioning. This leads to a tall forehead that is positioned too far back.

Children with Crouzon syndrome also have underdeveloped bones in the middle part of the face between the eyes and the mouth. The bones of the midface do not grow forward as they should. The slowed growth of the forehead and midface makes the child’s eyes appear large and prominent. In fact, the eyes are normal-sized in children with Crouzon syndrome, but they are not as well protected and surrounded by bony structures as they should be, making them appear large.

Additional characteristics include obstructive sleep apnea (due to the underdeveloped midface area), conductive hearing loss and a slightly higher incidence of Chiari malformations (parts of the brain are malformed and don’t function properly).  Children with Crouzon syndrome typically have normal intellect. 

Diagnosis of Crouzon syndrome

Most often, Crouzon syndrome is suspected at birth based on the characteristic appearance of the face and skull. The suspected diagnosis may be confirmed by genetic testing. 

Surgical Treatment

Treatment of children with Crouzon syndrome is complex and aimed at correcting the skull and midface abnormalities and treating obstructive sleep apnea.

  • Skull surgery: Most children with Crouzon syndrome will need two to four skull operations over a lifetime. The earliest skull surgery is usually done in the first 18 months of life.
  • Midface surgery: The most common surgery for moving the bones of the midface forward in Crouzon syndrome is called a LeFort III operation. This surgery is usually not done before your child is 6-8 years of age. The primary reasons for this surgery are severe obstructive sleep apnea which cannot be improved without surgery and significant concerns about the patient’s appearance.
  • Obstructive sleep apnea: Obstructive sleep apnea is due to the underdevelopment of the midface area. Your craniofacial team should monitor your child for sleep apnea. In mild cases, medications may be enough to improve breathing. If more significant obstruction occurs, a tonsillectomy or continuous positive airway pressure (CPAP) masks may help alleviate symptoms. Sometimes, a tracheostomy may be necessary for infants with Couzon syndrome to ensure adequate breathing.

Midface surgery may be needed as your child gets older to treat obstructive sleep apnea or to remove a tracheostomy placed in infancy.

The goal in all of these interventions is to ensure a good airway so that your child can get enough oxygen to help her develop to her fullest potential.

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