1/55. Midface distraction.Since the initial application of distraction osteogenesis to the human mandible by McCarthy, distraction osteogenesis has been used for gradual lengthening of the midface in children with syndromic craniosynostosis, cleft lip and palate, hemifacial microsomia, and midface hypoplasia from other causes. Both external and internal devices are available that permit midface distraction. The background of midface distraction and the development of a Modular Internal Distraction (MID) system that permits widespread use of easily customized, buried distraction devices throughout the craniofacial region are presented. The relative and potential clinical indications for distraction, treatment planning, patient preparation, and possible surgical orthodontic interactions during distraction, as well as a variety of case examples showing the MID system, are discussed.- - - - - - - - - - ranking = 1keywords = synostosis (Clic here for more details about this article) |
2/55. Fibroblast growth factor receptor mutational screening in newborns affected by metopic synostosis.A number of craniosynostotic disorders have recently been ascribed to mutations in genes coding for the fibroblast growth factor receptors(FGFRs). The common feature of these FGFR-associated conditions is the unilateral or bilateral premature ossification of the coronal suture. One distinct craniosynostotic condition is trigonocephaly, which results from the premature fusion of the metopic suture. Trigonocephaly mostly occurs as isolated cranial defect; however, the premature closure of the metopic suture may represent a feature of more complex craniosynostotic conditions in which a progressive involvement of other cranial sutures with age is observed. The possible involvement of mutated FGFRs in trigonocephaly was investigated in nine newborns affected by isolated premature synostosis of the metopic suture. All except one of these cases carried no mutations in the FGFR1-3 domains indicated as hot spots for craniosynostosis-associated mutations. A T(978)C transition in the FGFR2 exon IIIa was found in a patient who had a phenotype that apparently fitted the trigonocephalic condition at birth, but showed additional facial anomalies, which worsened progressively with age towards a Crouzon-like profile. The present finding points out the importance, from both diagnostic and prognostic points of view, of early FGFR mutational screening in craniosynostotic conditions, even in forms that apparently do not involve closure of the coronal suture at birth.- - - - - - - - - - ranking = 6keywords = synostosis (Clic here for more details about this article) |
3/55. Monobloc and midface distraction osteogenesis in pediatric patients with severe syndromal craniosynostosis.We present 2 children with severe syndromal craniosynostosis who were in need of urgent midface advancement surgery due to recurrent ocular dislocations (Pfeiffer's syndrome type II) or severe upper respiratory obstruction (Crouzon's syndrome). They were operated using distraction osteogenesis, with gradual midface or monobloc advancements. In the Pfeiffer patient, a maxillary distraction of 25 mm achieved effective cessation of ocular dislocations, whereas a 23-mm monobloc advancement in the Crouzon patient achieved cessation of nocturnal arterial desaturations. No major postoperative complications were recorded. Distraction osteogenesis has become a versatile and safe technique that allows for large skeletal advancements.- - - - - - - - - - ranking = 5keywords = synostosis (Clic here for more details about this article) |
4/55. Anomalous medial rectus muscle insertion in a child with craniosynostosis.INTRODUCTION: Oblique and vertical rectus muscle anomalies have been commonly reported in patients with craniofacial syndromes, while horizontal rectus muscle anomalies have been uncommonly reported. methods: Case report of a child with Crouzon's syndrome who was found to have an anomalous medial rectus muscle insertion at surgery. RESULTS: A bifid left medial rectus muscle insertion was found at surgery, requiring a small modification of the planned surgical procedure. CONCLUSION: Anomalies of extraocular muscles may be present in patients with craniofacial syndromes and strabismus surgeons should be prepared to modify their surgical plan when anomalous extraocular muscles are found.- - - - - - - - - - ranking = 4keywords = synostosis (Clic here for more details about this article) |
5/55. Subtle radiographic findings of achondroplasia in patients with Crouzon syndrome with acanthosis nigricans due to an Ala391Glu substitution in FGFR3.A unique type of craniofacial dysostosis, Crouzon syndrome with acanthosis nigricans (CAN), has been attributed to a specific substitution (Ala391Glu) in the fibroblast growth factor receptor 3 (FGFR3) gene. At birth, individuals with this disorder have craniosynostosis, ocular proptosis, midface hypoplasia, choanal atresia, hydrocephalus, and they experience the onset of acanthosis nigricans during childhood. We report three cases and compare the clinical characteristics of our cases with the previously reported cases of this disorder. Since the Ala391Glu substitution in FGFR3 is close to the substitutions in the transmembrane domain that result in achondroplasia, we carefully reviewed the skeletal findings in six patients. We identified subtle radiographic findings of achondroplasia in all six cases including narrow sacrosciatic notches, short vertebral bodies, lack of the normal increase in interpediculate distance from the upper lumbar vertebrae caudally, and broad, short metacarpals and phalanges. Even before acanthosis nigricans appears, the presence of choanal atresia and hydrocephalus in an individual with features of Crouzon syndrome should suggest the diagnosis of CAN, and subtle skeletal findings can lend further support to this diagnosis.- - - - - - - - - - ranking = 1keywords = synostosis (Clic here for more details about this article) |
6/55. pregnancy following preimplantation genetic diagnosis for Crouzon syndrome.Crouzon syndrome is a dominantly inherited craniosynostosis syndrome which is caused by mutations in the fibroblast growth factor receptor 2 gene (FGFR2). However, a specific point mutation in the FGFR3 gene has also been shown to result in Crouzon syndrome associated with acanthosis nigricans. We report here the first method for preimplantation genetic diagnosis (PGD) of Crouzon syndrome based on multiplex PCR amplification followed by the direct detection of the causative mutation by single-stranded conformational polymorphism (SSCP) analysis. A highly polymorphic short tandem repeat (STR) locus was simultaneously analysed as a control against some forms of contamination. The mutation, carried by the female partner, was a de-novo substitution at codon 338 of the FGFR2 gene. The couple were found to be informative at the D21S11 STR locus. Two clinical PGD cycles were performed, resulting in the biopsy of 36 blastomeres, 25 of which showed amplification at the FGFR2 locus. All of the cells showed expected genotypes at the D21S11 locus with only one incidence of allele drop-out. A total of five embryos were transferred, two in the first cycle and three in the second, resulting in a singleton pregnancy.- - - - - - - - - - ranking = 1keywords = synostosis (Clic here for more details about this article) |
7/55. Midface distraction following Le Fort III and monobloc osteotomies: problems and solutions.Distraction osteogenesis has been used increasingly for midfacial advancement in patients with syndromic craniosynostosis and in severe developmental hypoplasia of the midface. In these patients, the degree of advancement required is often so great that restriction of the adjacent soft tissues may preclude stable advancement in one stage. Whereas distraction is an ideal solution by which to gradually lengthen both the bones and the soft tissues, potential problems remain in translating the distraction forces to the midface. In these patients, severe developmental hypoplasia may be associated with weak union between the zygoma and the maxilla, increasing the chance of zygomaticomaxillary dysjunction when using internal devices that translate distraction force to the maxilla through the zygoma. Eight cases are reported in which either internal or external distraction systems were used for midface advancement following Le Fort III (n = 7) or monobloc (n = 1) osteotomies. Cases of patients in whom hypoplasia at the zygomaticomaxillary junction altered or impaired plans for midface distraction were reported from three host institutions. Seven patients had midface hypoplasia associated with syndromic craniosynostosis, and one patient had severe developmental midface hypoplasia. The distraction protocol was modified to successfully complete midface advancement in light of weakness at the zygomaticomaxillary junction in seven patients. Modifications included change from an internal to an external distraction system in two patients, rigid fixation and bone graft stabilization of the midface in one patient, and plate stabilization of a fractured or unstable zygomaticomaxillary junction followed by resumption of internal distraction in four patients. Previous infection and bone loss involving both malar complexes precluded one patient from being a candidate for an internal distraction system. Using a problem-based approach, successful advancement of the midface ranging from 9 to 26 mm at the occlusal level as measured by preoperative and postoperative cephalograms was undergone by all patients. Advantages and disadvantages of the respective distraction systems are reviewed to better understand unique patient characteristics leading to the successful use of these devices for correction of severe midface hypoplasia.- - - - - - - - - - ranking = 2keywords = synostosis (Clic here for more details about this article) |
8/55. encephalocele as a late complication of cranial vault reconstruction in a patient with Crouzon's syndrome.encephalocele is a rare late complication of craniosynostosis repair. An undiagnosed nick to the dura is the etiology of this complication. It usually presents within a few months to years after repair. This case report describes a patient with Crouzon's disease who had a craniosynostosis repair as an infant and presents 22 years later with an encephalocele. The patient had a thorough physical exam, 2D, and 3D CT Scans as a preoperative workup. Surgical intervention included repair of the encephalocele, cranialization of the frontal sinus with bone grafting, and Lefort III osteomies for mid face advancement. The patient benefited from a two-team simultaneous approach between neurosurgery and Plastic Surgery. The patient also benefited from an aggressive one-stage repair of all her defects and deformities.- - - - - - - - - - ranking = 2keywords = synostosis (Clic here for more details about this article) |
9/55. Tracheal cartilaginous sleeve in Crouzon syndrome.Tracheal cartilaginous sleeve (TCS) is a congenital malformation characterized by fusion of the tracheal arches that may be isolated to a few tracheal arches, include the entire trachea, or extend beyond the carina into the bronchi. TCS has been reported only in children with craniosynostosis. Seven cases of TCS and Crouzon syndrome (CS) are mentioned in the literature. In addition to our case study, a review of the literature on TCS in CS, a classification of TCS and treatment options will be provided. tracheotomy and frequent airway endoscopy coupled with a keen understanding of the shifting sites of obstruction will permit longterm survival in patients with TCS and CS.- - - - - - - - - - ranking = 1keywords = synostosis (Clic here for more details about this article) |
10/55. A novel fibroblast growth factor receptor 2 mutation in Crouzon syndrome associated with Chiari type I malformation and syringomyelia.OBJECT: It has been reported that due to premature synostosis of the lambdoid suture in the first 24 months of life, more than 70% of patients with Crouzon syndrome concurrently suffer from chronic tonsillar herniation (Chiari Type I malformation) and some (20%) associated syringomyelia. The goal of the present study was to examine mutations in the fibroblast growth factor receptor (FGFR) genes in Crouzon syndrome and its related conditions. methods: Five patients were studied: three with Crouzon syndrome (one sporadic and two familial), one with sporadic Chiari I with syringomyelia, and one with unilateral lambdoid synostosis. Deoxyribonucleic acid was screened for FGFR1-3 mutations by using single-strand conformational polymorphism and subsequent direct sequencing. Two types of missense mutations were detected in the FGFR2 gene, Cys342Trp (1205, TGC --> TGG) in a patient with sporadic Crouzon syndrome and Tyr281Cys (1021, TAC --> TGC) in two siblings (brother and sister) with familial Crouzon syndrome, respectively. The former has been reported only in sporadic cases but the latter has not previously been identified. A polymorphism in the FGFR3 gene, Asn294Asn (882, AAT --> AAC), was also detected in three patients. No mutation was found in the patient with sporadic Chiari I with syringomyelia. CONCLUSIONS: The FGFR2 missense mutation was detected in Crouzon syndrome but not in sporadic Chiari I with syringomyelia or lambdoid synostosis. A novel FGFR2 mutation, Tyr281Cys, was found in familial Crouzon syndrome with Chiari I and syringomyelia. It may be informative to look for this in patients with Crouzon syndrome and associated syringomyelia.- - - - - - - - - - ranking = 3keywords = synostosis (Clic here for more details about this article) |
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