The craniofacial dysostosis syndromes are a group of similar, inherited, congenital anomalies that affect the skull, face, and sometimes the limbs. Typically, there is fusion of the coronal sutures of the skull (bicoronal synostosis), that creates a skull that is short from front to back, wide, and tall. (For a detailed discussion of the cranial sutures, please see the Craniosynostosis section.) In addition, the bones of the midface-from the orbits (eye sockets) down to and including the upper jaw-do not grow forward normally, resulting in a retruded or concave face, with an “underbite.” Finally, depending upon the particular syndrome, a variety of hand (and sometimes foot) abnormalities can occur, such as webbed fingers and underdeveloped thumbs.
Is this condition painful?
In general, craniosynostosis is not a painful condition. However, if there is increased pressure upon the brain, this can cause headaches, irritability, nausea, and vomiting. Occasionally, in cases where the fingers are tightly webbed together (e.g. Apert’s syndrome), infections around the nails or skin breakdown can occur, causing some discomfort. If the orbits (the bony eye sockets) are really shallow, the corneas may become dry and irritated, which can also cause discomfort.
What are the different types of craniofacial dysostosis syndromes?
The more common of these syndromes include Apert’s syndrome, Crouzon’s syndrome, and Pfeiffer’s syndrome. However there are several others, such as Nager’s syndrome, Carpenter’s syndrome, Jackson-Weiss syndrome, and Saethre-Chotzen syndrome. In Apert’s syndrome, there is bicoronal synostosis, midface retrusion, and symmetric syndactyly (webbing of the digits) in both the hands and feet. Crouzon’s syndrome is characterized by bicoronal synostosis and midface retrusion, but normal hands and feet. Pfeiffer’s syndrome is also characterized by bicoronal synostosis, and midface retrusion, with broad, angulated thumbs and broad great toes. The other syndromes represent variations on this general theme.
Who gets these syndromes?
The craniofacial dysostosis syndromes are inheritable. The gene mutation for each syndrome has been identified. Almost all of the syndromes are inherited in an autosomal dominant fashion, meaning that there is a 50% likelihood of recurrence of the syndrome in the offspring of the affected individual. Often, the parents of these children are not affected, and the gene mutation arises spontaneously during development. However, the severity of the syndrome may vary from one generation to the next, so that it may not have been detected in a parent, for example, until a more severely-affected child was born.
What causes these syndromes?
As mentioned above, these syndromes are caused by genetic mutations. The fibroblast growth factor receptor genes are primarily affected.
What are the main issues related to the craniofacial dysostosis syndromes?
The most important issue related to craniosynostosis is the potential for increased pressure on the brain. When there is excessive pressure on the brain, problems with neural development, including visual problems can occur. These may be subtle or mild, such as learning disabilities, or more severe, such as mental retardation and loss of vision. Most children never develop such severe symptoms. However, because we cannot predict which children will have these problems, treatment of craniosynostosis is recommended to prevent the possible increased intracranial pressure.
In addition, there are problems associated with the poor growth of the midface in these patients. These patients tend to have an underbite, and can also have problems with their eyes if the orbits (eye sockets) are very shallow. Obstructive sleep apnea can be a problem for these children because of the midface retrusion, which can cause narrowing of the airway.
Are there other problems that occur commonly with these syndromes?
Depending upon the particular syndrome, there may be problems in other parts of the body, particularly the hands, as mentioned above. Some of these children also have cleft palates.
In addition, in some cases, the muscles of the eyes do not function normally and may require surgery, and there may be abnormalities of the upper eyelids, such as drooping. There may be abnormalities of the cervical spine in some patients. Because such associated conditions can occur, all children with these syndromes are evaluated by a multidisciplinary group of specialists who can detect these problems.
What is the treatment for babies with craniofacial dysostosis?
While every patient is treated individually, with treatment plans made specifically for him or her, some generalizations are possible. Treatment usually begins with the craniosynostosis. Treatment for craniosynostosis is surgical. Babies with craniosynostosis are examined early in life by members of the craniofacial treatment team: a pediatrician who specializes in treating infants with craniofacial anomalies, a geneticist, a craniofacial surgeon, a neurosurgeon, and an ophthalmologist. Depending on the particular case, other specialists may be involved also. A computerized tomography scan (CT scan)—a special type of x-ray—is performed to study the bones of the skull and the brain. If there are no signs of increased intracranial pressure by physical examination or by CT scan, then most children will have their surgery at approximately one year of age. If there is increased intracranial pressure, then surgery is performed sooner.
The surgery is performed jointly by the craniofacial surgeon and the neurosurgeon. The skull is enlarged, or expanded, by removing and reshaping the bones of the skull to give the brain room to grow and also to correct the abnormal shapes that occur as a result of the various types of craniosynostosis. While this is a very specialized and complex surgical procedure, it is now performed safely and effectively with modern anesthetic and surgical techniques.
Other surgical procedures are dependent upon the unique features in each syndrome. The child may need to have a surgical procedure to move the midface forward to correct problems such as a severe underbite and sleep apnea. More than one jaw surgery is usually required to achive a normal relationship of the upper and lower teeth. Cleft palate repair is required in some cases, and a variety of hand surgery procedures may be required in certain syndromes.
What is done between the time my baby is born and the first surgery?
After the initial Craniofacial Team evaluation, described above, the child is evaluated periodically to ensure that he or she is growing and developing normally and that there is no sign of increased intracranial pressure. The CT scan may be repeated at some point before the surgery. Your surgeons will meet with you several times to examine your baby and to ensure that all of your questions about the surgery are answered and that you feel comfortable with the whole process.
What sorts of specialists will be involved in my baby’s care?
The optimal treatment of children with these complex syndromes is achieved in a multidisciplinary setting. As noted above, these children may have a number of other medical issues that must be addressed. Usually, the specialists involved include the craniofacial surgeon (a plastic surgeon who has done additional specialized training), a neurosurgeon, a pediatric ophthalmologist, a developmental pediatrician, a geneticist, the pediatric plastic surgery nurse, and an orthodontist.
Will we get to know our surgeon?
Because children with craniofacial syndromes are followed closely before, during, and after their surgery, you will become very familiar with your surgeons. Treatment is not finished after the surgery, because it is important for us to continue to monitor your child’s growth and development over the long term. This long-term surveillance involves physical examinations and periodic CT scans to ensure that there are no signs of any problems. Your surgeons will guide you and help you through the surgery and postoperative period. In addition, children with these syndromes require multiple surgical procedures throughout their childhood and adolescence, so they and their families often develop a close bond with their surgeon.