Muenke syndrome is a craniofacial syndrome characterized in part by premature fusion of the cranial sutures, or craniosynostosis. It is the most common syndrome associated with craniosynostosis, occurring in approximately 1 in 30,000 births.
Children with Muenke syndrome typically have premature fusion of the coronal sutures. In approximately 70% of the cases, both coronal sutures are fused, which is called bicoronal synostosis. Other patients have involvement of only one of the coronal sutures, which is called unicoronal synostosis. Rarely, other cranial sutures may be involved as well. Early fusion of the cranial sutures causes restriction in the growth of the skull along that suture, resulting in a characteristic head shape. Patients with bicoronal synostosis generally have a short skull length, called brachycephaly. Patients with unicoronal synostosis develop plagiocephaly, which is an asymmetric head shape.
Children with Muenke syndrome may have other symptoms in addition to craniosynostosis. Some degree of sensorineural hearing loss occurs in the majority of patients. Patients with sensorineural hearing loss have normally developed outer ears, but have problems with the inner ear (cochlea,) or the ability to transmit nerve signals from the ear to the brain. Epilepsy can occur in approximately 10% of patients. Other symptoms and signs may include strabismus (misalignment of the eyes) and mild abnormalities of the fingers or toes. Some patients have learning disabilities or developmental delay, although this tends to be mild.
What Causes Muenke Syndrome?
Muenke syndrome is a genetic condition. It is caused by a mutation in the Fibroblast Growth Factor Receptor 3 (FGFR3) gene. In the majority of cases, this mutation occurs sporadically during development and is not inherited from the parents. However, once the mutation occurs, it is passed to children in an autosomal dominant pattern. This means that only one copy of the gene mutation is needed for a child to inherit the syndrome. Children of patients with Muenke syndrome have a 50% chance of inheriting the syndrome.
What Treatments Are Available For Patients With Muenke Syndrome?
Patients with Muenke syndrome benefit from a multidisciplinary team with experience in treating craniosynostosis syndromes. This team approach includes coordinated care between the craniofacial surgeons, neurosurgeons, otolaryngologists (ear, nose , and throat doctors,), audiologists, speech specialists, orthodontists, and dentists.
The first few years of life are a time of rapid brain growth. Because of the fused cranial sutures, the skulls of patients with craniosynostosis have difficulty accommodating this rapid growth. This may lead to elevated intracranial pressure. For this reason, along with the abnormal shape of the skull, patients with Muenke syndrome and craniosynostosis benefit from cranial vault remodeling during the first year of life. This is typically done at between 6-12 months of age. Please see the craniosynostosis page for more detail.
Patients with Muenke syndrome are then followed by the multidisciplinary team throughout childhood for monitoring and treatment of other symptoms. Sensorineural hearing loss may be amenable to treatment with hearing aids or cochlear implants, depending on the severity.
If you would like more information about this craniofacial anomaly, please contact the Craniofacial Team of Texas by calling 512-377-1142 to schedule an appointment or complete an online appointment request.