Disclaimer: The information contained within the Grand Rounds Archive is intended for use by doctors and other health care professionals. These documents were prepared by resident physicians for presentation and discussion at a conference held at Baylor College of Medicine in Houston, Texas. No guarantees are made with respect to accuracy or timeliness of this material. This material should not be used as a basis for treatment decisions, and is not a substitute for professional consultation and/or peer-reviewed medical literature. Craniosynostosis Syndromes Craniosynostosis arises from the premature closure of cranial suture lines, which leads to maldevelopment of the cranial cavity and other craniofacial features. It is a feature of a multitude of medical conditions. These can be grossly divided into those that are associated with syndromes and those that are not. The syndromes associated with craniosynostosis can be further broken down by etiology into those resulting from a monogenic, or Mendelian, mode of inheritance, from specific chromosomal defects, from environmental teratogens, and from other factors which are as yet unknown. The syndromes covered in this review are inherited in a monogenic fashion, and represent some of the more common syndromes. Apert's syndrome is characterized by irregular craniosynostosis, midfacial hypoplasia, and symmetric syndactyly of the hands and feet. The incidence is quoted at 1 in 115,000 births, although this may be an underestimate. Cases are usually sporadic mutations, although an autosomal dominant mode of transmission from affected parents has been shown. Crouzon's syndrome is closely related to that of Apert's. Its chief components are cranial synostosis, maxillary hypoplasia, shallow orbits and ocular proptosis. Unlike Apert's, there are no abnormalities of the hands and feet. Other facial features which distinguish it from Apert's are a more retruded appearance to the forehead, more severe proptosis, normal orientation of the palpebral fissures, and a more normal appearance of the mouth. Crouzon's follows an autosomal dominant mode of transmission. Approximately 50% represent sporadic mutations, while 40% are familial. Pfeiffer's disease is also a close relative of Apert's syndrome, although is less severe. It is characterized by acrocephaly, broad thumbs and great toes and partial soft tissue syndactyly of the hands. It also follows an autosomal dominant mode of transmission. Most cases are familial, but sporadic cases exist. Saethre-Chotzen syndrome has a more variable presentation. The most consistent features of this syndrome include acrocephaly, hypertelorism, nasal septal deviation, lid ptosis, and mild syndactyly of the hands and feet. Saethre-Chotzen is possibly the most common of all the craniosynostosis syndromes. Despite its commonness, however, the syndrome is probably underdiagnosed. This is due ot the great variability in expression even within affected families, as well as the relative mildness of the abnormalities. The otolaryngologic features of craniosynostosis are diverse, but can be broken down into two basic categories: hearing loss and otologic problems, and problems with the airway. Otologic problems exist in all portions of the ear. External ear abnormalities include low set, small or posteriorly rotated ears, such as those seen in our Apert's, Pfeiffer's and Saethre-Chotzen patients. A prominent antihelical fold is frequently seen in patients with Saethre-Chotzen. External canal atresia is also a feature of craniosynostosis syndromes. It was found in 13% of patients with Crouzon's syndrome and is also reported to be quite common with Pfeiffer's syndrome. Middle ear abnormalities consist of both congenital ossicular fixation and eustachian tube dysfunction. Stapes fixation is the most classically described malformation in patients with Apert's syndrome. Bergstrom reported a perilymph gusher during stapedectomy in one patient operated on for stapes fixation. Because of this complication and the frequency of middle ear effusion and infection, the performance of stapedectomy has been condemned by a number of authors, while other simply warn that it should be approached with caution. Ossicular fixation is also a feature of other craniosynostosis syndromes, including Crouzon's, in which lateral chain abnormalities may be found. Eustachian tube dysfunction leading to effusions, perforation, and cholesteatoma is thought to be secondary to altered nasopharyngeal and skull base anatomy and is extremely common. Significantly, as these patients grow, the relative hypoplasia of the skull base is often accentuated and middle ear pathology frequently persists into adulthood. Inner ear pathology is poorly characterized in these patients, although there is an increased incidence of sensorineural hearing loss. Airway problems can be broken down into those arising from the nasal passages, nasopharynx, palate or trachea. Nasal septal deviation is a common feature of craniosynostosis patients and is considered a principle finding in Saethre-Chotzen syndrome. Narrowing of the nasal passages arises form maxillary hypoplasia. Although choanal atresia can occur, the usual picture is one of generalized narrowing. The nasopharynx is very shallow due to hypoplasia of the maxilla and the altered angulation of the skull base. Finally, palatal abnormalities further impinge on the nasopharynx. These deformities may consist of arched or ridged palates, or of increased thickness to the soft tissue. The degree of airway obstruction is variable in these patients, with Apert's syndrome being among the worst. Reports of complications including cor pulmonale and even death from airway obstruction have been made. Lower airway obstruction may result from a number of abnormalities, including subglottic stenosis and vertically fused tracheal cartilage. Subglottic stenosis is especially common in Crouzon's patients. A vertically fused tracheal cartilage has been reported in cases of Apert's, Crouzon's and Pfeiffer's. With this abnormality, the entire trachea is encased in a tube of nonsegmented cartilage. These children can be quite difficult to manage and usually present with episodes of recurrent lower respiratory tract infections, reactive airway disease, and chronically retained secretions. Treatment of craniosynostosis is by way of a multidisciplinary team. Frequently, cranial decompression is required to allow for normal expansion of the brain and to improve the aesthetic appearance of the cranium. Forehead and midface advancement are usually performed early in childhood. Treatment of airway obstruction is dependent on the severity of the obstruction. Conservative therapy, including use of decongestants and an oral airway have been used effectively by some authors. Nasal stents may also be effective in improving nasal patency. Intubation may be needed as a temporizing measure, and tracheotomy may be required in patients not responsive to more conservative measures. Finally, midface advancement may help to improve the airway obstruction by widening the nasopharynx. Treatment of the otologic manifestations of craniosynostosis include the initial evaluation of hearing to rule out congenital hearing loss. Surgical management of middle ear disease including frequent need for ventilation tubes is essential. Finally, longterm otologic followup in these children is essential because of the often progressive nature of their deformities. Case Presentation A white male term infant was born by cesarean section to a 30-year-old G2,P0-1,Ab1 mother. Dysmorphic features were evident at birth, consisting of asymmetric brachycephaly, maxillary hypoplasia, proptosis, trapezoid mouth, high grooved palate and symmetrical syndactyly of the hands and feet. A diagnosis of Apert's syndrome was made. The otolaryngology team was consulted for evaluation and management of obstructive breathing requiring intubation, feeding difficulties, and potential otologic abnormalities. An ABR performed at this time was interpreted as normal. Evaluation of the upper aerodigestive tract revealed the likely cause of the obstructive breathing to be significantly narrowed nasal passages. There was also noted to be pharyngeal incoordination and pooling of secretions. Initial management consisted of placement of nasal stents on the third day of life, which allowed the patient to be extubated. At one month of age, he underwent coronal and supraorbital strip craniectomies. During a brief discharge from the hospital, he was noted to have recurrent apnea, as well as difficulty tolerating feeds. A sleep study revealed repeated apneic episodes associated with upper airway obstruction despite the nasal stents. CPAP trials were poorly tolerated. A tracheotomy was performed in conjunction with placement of a gastrostomy tube. He has had no further apnea and is steadily gaining weight. Craniofacial advancement was performed at six months of age. Bibliography Bartsocas CS, Weber AL, Crawford JD. Acrocephalosyndactyly type III: Chotzen's syndrome. J Pediatr 1970;77:267-272. Bergstrom L, Neblett LM, Hemenway WG. Otologic manifestations of acrocephalosyndactyly. Arch Otolaryngol 1972;96:117-123. Blank CE. Apert's syndrome (a type of acrocephalosyndactyly) observations on a British series of thirtynine cases. Ann Hum Genet 1960;24:151-163. Brueton LA, Herwerden L, Chotai KA, Winter RM. The mapping of a gene for craniosynostosis: evidence for linkage of the SaethreChotzen syndrome to distal chromosome 7p. J Med Genet 1992;29:681-685. Cohen MM, editor. Craniosynostosis: Diagnosis, Evaluation, and Management. New York: Raven Press, 1986. Cohen MM. Craniosynostosis update 1987. Am J Med Genet Suppl 1988;4:99-148. Crysdale WS. Otorhinolaryngologic problems in patients with craniofacial anomalies. Otolaryngol Clin North Am 1981;14:145-155. Del Campo AF. Rigid fixation and osteotomy design in frontal orbital advancement osteotomies. Clin Plast Surg 1989;16:205-211. Friedman JM, Hanson JW, Graham B, Smith DW. SaethreChotzen syndrome: a broad and variable pattern of skeletal malformations. J Pediatr 1977;91:929-933. GershoniBaruch R. Carpenter syndrome: marked variability of expression to include the Summitt and Goodman syndromes. Am J Med Genet 1990;35:236-240. Gould HJ, Caldarelli DD. Hearing and otopathology in Apert syndrome. Arch Otolaryngol 1982;108:347-349. Inglis AF, Kokesh J, Siebert J, Richardson MA. Vertically fused tracheal cartilage: an underrecognized anomaly. Arch Otolaryngol Head Neck Surg 1992;118:436-438. Juehlbauer W, Anderl H, Heeckt P, et al. Early operation in craniofacial dysostosis. World J Surg 1989;13:366-372. Kreiborg S, Pruzansky S, Pashayan H. The SaethreChotzen syndrome. Teratol 1972;6:287-294. Lauritzen C, Lilja J, Jarlstedt J. Airway obstruction and sleep apnea in children with craniofacial anomalies. Plast Reconstr Surg 1986;77:15. Lindsay JR, Black FO, Donnelly WH. Acrocephalosyndactyly (Apert's syndrome): temporal bone findings. Ann Otol 1975;84:174-178. Marchac D, Renier D. Craniosynostosis. World J Surg 1989;13:358-365. Martsolf JT, Cracco JB, Carpenter GG, O'Hara E. Pfeiffer syndrome: an unusual type of acrocephalosyndactyly with broad thumbs and great toes. Am J Dis Child 1971;121:257-262. McGill T. Otolaryngologic aspects of Apert syndrome. Clin Plast Surg 1991;18:309-313. PetersonFalzone SJ, Pruzansky S, Parris PJ, Laffer JL. Nasopharyngeal dysmorphology in the syndromes of Apert and Crouzon. Cleft Palate J 1981;18:237-250. Robinson LK, James HE, Mubarak SJ, et al. Carpenter syndrome: natural history and clinical spectrum. Am J Med Genet 1985;20:461-469. Schafer ME. Upper airway obstruction and sleep disorders in children with craniofacial anomalies. Clin Plast Surg 1982;9:555-567. Stewart RE, Dixon G, Cohen A. The pathogenesis of premature craniosynostosis in acrocephalosyndactyly (Apert's syndrome). Plast Reconstr Surg 1977;59:699-707. Stool SE, Houlihan R. Otolaryngologic management of craniofacial anomalies. Otolaryngol Clin North Am 1977;10:41-44. Temtamy SA. Carpenter's syndrome: acrocephalopolysyndactyly. An autosomal recessive syndrome. J Pediatr 1966;69:111-120. Grand Rounds Archive | Department Home page BCM Public | BCM Intranet | Privacy Notices | Contact BCM | BCM Site Map | ©2001-2006 Baylor College of Medicine
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