Crouzon syndrome is a congenital disorder characterised by premature closure (synostosis) of the coronal sutures, and less frequently sagittal or lambdoidal skull sutures. This results in a dysmorphic appearance of skull and face, with a high forehead, flattened occiput and brachycephaly. In addition to the craniosynostosis, affected children may also have abnormal fusion of the bones of the skull base and midface, resulting in maxillary hypoplasia, high arched palate and shallow orbits, causing pronounced exophthalmos. Crouzon occurs in approximately 1 in 25,000 births, and is due to a mutation in the fibroblast growth factor receptor (FGFR) 2 gene on chromosome 10 (1). It may be inherited in an autosomal dominant fashion or occur sporadically as a spontaneous mutation. It has a male:female predominance of 3:1. The clinical appearance of Crouzon syndrome may vary significantly, from subtle facial features to severe dysplasia and significant comorbidity.
Premature synostosis of cranial sutures can produce a number of effects in the growing child, although the degree of severity is variable. The combination of a reduced intra-cranial capacity and a growing brain may result in raised intracranial pressure (ICP), optic atrophy, deafness, seizures and rarely mental impairment.
Extended dysostosis of facial and cervical bones and subsequent soft tissue abnormalities may comprise the upper airways and obstructive sleep apnoea (OSA) is common in Crouzon Syndrome. Spine abnormalities may be present, can reduce cervical movement and together with nasal and pharyngeal obstructions, a difficult airway scenario has to be anticipated (2;3).
Crouzon syndrome may be associated with a patent ductus arteriosus (PDA) and aortic coarctation (AoC).
Crouzon, Apert and Pfeiffer syndromes are the most recognizable of the syndromic craniosynostoses.