Complex Airway Management in Patients with Tracheal Cartilaginous Sleeves.

OBJECTIVES/HYPOTHESIS: A tracheal cartilaginous sleeve (TCS) is a rare anomaly characterized by anterior fusion of tracheal cartilages. TCS is associated with syndromic craniosynostoses including Apert, Crouzon and Pfeiffer syndromes and FGFR2, FGFR3, and TWIST1 variants. This study presents a 30-year review of patients with syndromic craniosynostosis and TCS and describes diagnostic methods, genetic variants, surgical interventions, and long-term outcomes. STUDY DESIGN: Retrospective, single-institution review. METHODS: This review included patients with syndromic craniosynostosis and TCS treated at Seattle Children's Hospital from 1990 to 2020. Tracheostomy, genetic variants, and additional surgery were primary measures. Fisher's exact test compared need for tracheostomy in patients with proposed high-risk (FGFR2 p.W290 or FGFR2 p.C342) versus low-risk genetic variants. RESULTS: Thirty patients with TCS were identified. Average age at diagnosis was 12 months (range 2-weeks to 7.9-years; standard deviation 19.8 months). Syndromes included Pfeiffer (37%), Apert (37%), and Crouzon (26%). Severe obstructive sleep apnea was present in 76% of patients. Tracheostomy was performed in 17 patients (57%); five were successfully decannulated. Additional interventions included adenotonsillectomy (57%), nasal (20%), laryngeal (17%), and craniofacial skeletal surgery (87%). All patients with Pfeiffer syndrome and FGFR2 p.W290C variants and 83% of patients with FGFR2 p.C342 variants required tracheostomy, differing from other variants (P = .02, odds ratio 33, 95% confidence interval 1.56-697.96). One patient (3%) died. CONCLUSION: TCS contributes to multilevel airway obstruction in patients with syndromic craniosynostosis. Genetic testing in patients with FGFR2-related syndromic craniosynostoses may identify those at risk of TCS and facilitate early intervention. A better understanding of this patient population may foster individualized airway management strategies and improve outcomes. LEVEL OF EVIDENCE: 4 Laryngoscope, 132:215-221, 2022.

Airway Growth in Preoperative Patients with Crouzon Syndrome.

Background: Obstructive sleep apnea is common in patients with Crouzon syndrome, yet it may be caused by multiple factors. This study aims to investigate the natural history of airway development in preoperative Crouzon patients, from infants to adults. Methods: Preoperative computed tomography (CT) scans (Crouzon syndrome, n = 73; control, n = 87) were divided into five age subgroups. CT scans were measured using Materialise software. Results: Before 6 months of age, nasal airway volume in patients with Crouzon syndrome was smaller than normal by 37% (p = 0.002), and the cross-sectional area at the choana reduced by 45% (p < 0.001). The reduction of nasal airway volume and cross-sectional area reached their nadir at 2 years of age, with shortening of 44% and 63% (both p < 0.001), respectively. They gradually caught up to normal dimensions after 6 years of age. Between 2 and 6 years, the pharyngeal airway in patients with Crouzon syndrome reduced 44% (p = 0.011) compared with controls. However, the airway cross-sectional area at condylion and gonion levels was less than normal, before 6 months (35%, p = 0.024) and (44%, p = 0.006) after 2 years of age, respectively. This reduction remains into adulthood. Conclusion: Nasal airway volume is more limited in children with Crouzon syndrome who are younger than 2 years of age. Whereas after 2 years of age, the pharyngeal airway develops significant volume restriction, leading to timing and specific treatment area foci based on the site of temporal maximal constriction.

Mandibular Spatial Reorientation and Morphological Alteration of Crouzon and Apert Syndrome.

BACKGROUND: From infancy to adulthood, the mandible develops increased ramus height, prominence of the chin, and laterally widened gonial angles. In Crouzon and Apert syndromes, both relative retrognathia and prognathic jaws have been reported. Growth is influenced by a variety of factors, including the growth and relative position of the skull base, functional coordination, and the spatial influence of the laryngopharynx. Thus, this study aimed to explore in detail the evolution of the mandible in both syndromes and its relationship with the entire facial structure and skull base. METHODS: One hundred twenty-three preoperative computed tomographic scans (Crouzon, n = 36; Apert, n = 33; control, n = 54) were included and divided into 5 age subgroups. Computed tomographic scans were measured using Materialise software. Cephalometrics relating to the mandible, facial structures, and cranial base were collected. Statistical analyses were performed using t test and statistical power analysis. RESULTS: In Crouzon syndrome, the angle between the cranial base and gnathion was increased prior to 6 months of age by 10.29 degrees (P < 0.001) and by adulthood to 11.95 degrees (P = 0.003) compared with normal. After 6 months of age, the distance between bilateral mandibular condylions (COR-COL) was narrower by 15% (P < 0.001) in Crouzon syndrome compared with control subjects. Before 6 months of age, Apert COR-COL decreased 16% (P < 0.001) compared with control subjects and 13% (P = 0.006) narrower than Crouzon. During 2 to 6 years of age, Apert mandibular ramus height caught up to, and became longer than, Crouzon by 12% (P = 0.011). The nasion-sella-articulare angle of the Apert skull was 5.04 degrees (P < 0.001) less than Crouzon overall. CONCLUSIONS: In Crouzon syndrome, the changes of the spatial relationship of the mandible to the cranial base develop earlier than the mandibular shape deformity, whereas in Apert syndrome, the spatial and morphological changes are synchronous. The morphological changes of the mandible are disproportional in 3 directions, initially significant shortening of the mandibular width and length, and, subsequently, reduced height. Crouzon has more shortening in mandibular height compared with Apert, reflecting the more shortened posterior cranial base length. The narrowed angle between the mandible and the posterior cranial base in Apert skulls is consistent with the more limited nasopharyngeal and oropharyngeal airway space.

Reductions in ATPase activity, actin sliding velocity, and myofibril stability yield muscle dysfunction in Drosophila models of myosin-based Freeman-Sheldon syndrome.

Using Drosophila melanogaster, we created the first animal models for myosin-based Freeman-Sheldon syndrome (FSS), a dominant form of distal arthrogryposis defined by congenital facial and distal skeletal muscle contractures. Electron microscopy of homozygous mutant indirect flight muscles showed normal (Y583S) or altered (T178I, R672C) myofibril assembly followed by progressive disruption of the myofilament lattice. In contrast, all alleles permitted normal myofibril assembly in the heterozygous state but caused myofibrillar disruption during aging. The severity of myofibril defects in heterozygotes correlated with the level of flight impairment. Thus our Drosophila models mimic the human condition in that FSS mutations are dominant and display varied degrees of phenotypic severity. Molecular modeling indicates that the mutations disrupt communication between the nucleotide-binding site of myosin and its lever arm that drives force production. Each mutant myosin showed reduced in vitro actin sliding velocity, with the two more severe alleles significantly decreasing the catalytic efficiency of actin-activated ATP hydrolysis. The observed reductions in actin motility and catalytic efficiency may serve as the mechanistic basis of the progressive myofibrillar disarray observed in the Drosophila models as well as the prolonged contractile activity responsible for skeletal muscle contractures in FSS patients.

Syndromic craniosynostosis: neuropsycholinguistic abilities and imaging analysis of the central nervous system.

OBJECTIVE: To characterize patients with syndromic craniosynostosis with respect to their neuropsycholinguistic abilities and to present these findings together with the brain abnormalities. METHODS: Eighteen patients with a diagnosis of syndromic craniosynostosis were studied. Eight patients had Apert syndrome and 10 had Crouzon syndrome. They were submitted to phonological evaluation, neuropsychological evaluation and magnetic resonance imaging of the brain. The phonological evaluation was done by behavioral observation of the language, the Peabody test, Token test and a school achievement test. The neuropsychological evaluation included the WISC III and WAIS tests. RESULTS: Abnormalities in language abilities were observed and the school achievement test showed abnormalities in 66.67% of the patients. A normal intelligence quotient was observed in 39.3% of the patients, and congenital abnormalities of the central nervous system were observed in 46.4% of the patients. CONCLUSION: Abnormalities of language abilities were observed in the majority of patients with syndromic craniosynostosis, and low cognitive performance was also observed.

Syndromic craniosynostosis: neuropsycholinguistic abilities and imaging analysis of the central nervous system / Craniossinostoses sindrômicas: habilidades neuropsicolinguísticas e análise por imagem do sistema nervoso central

ABSTRACT Objective: To characterize patients with syndromic craniosynostosis with respect to their neuropsycholinguistic abilities and to present these findings together with the brain abnormalities. Methods: Eighteen patients with a diagnosis of syndromic craniosynostosis were studied. Eight patients had Apert syndrome and 10 had Crouzon syndrome. They were submitted to phonological evaluation, neuropsychological evaluation and magnetic resonance imaging of the brain. The phonological evaluation was done by behavioral observation of the language, the Peabody test, Token test and a school achievement test. The neuropsychological evaluation included the WISC III and WAIS tests. Results: Abnormalities in language abilities were observed and the school achievement test showed abnormalities in 66.67% of the patients. A normal intelligence quotient was observed in 39.3% of the patients, and congenital abnormalities of the central nervous system were observed in 46.4% of the patients. Conclusion: Abnormalities of language abilities were observed in the majority of patients with syndromic craniosynostosis, and low cognitive performance was also observed.

RESUMO Objetivo: Caracterizar as habilidades neuropsicolinguísticas de indivíduos com craniossinostoses sindrômicas e apresentar esses achados com as anomalias do sistema nervoso central. Métodos: Participaram do estudo 18 sujeitos com diagnóstico clínico de craniossinostose sindrômica, 44,4% com a síndrome de Apert e 55,6% síndrome de Crouzon. Todos os sujeitos foram submetidos a avaliação fonoaudiológica, psicológica e exames de ressonância magnética do encéfalo. A avaliação fonoaudiológica foi contemplada pela Observação Comportamental da Linguagem, Teste Peabody (TVIP), Teste Token e Teste de Desempenho Escolar (TDE); enquanto a psicológica utilizou a WISC-III e a WAIS. Resultados: Observou-se alteração nas habilidades de linguagem em todos os protocolos utilizados, sendo o TDE o que apresentou maior porcentagem de alteração (66,67%).A avaliação cognitiva evidenciou quociente de inteligência dentro da média em 39,3% dos sujeitos, enquanto que 46,4% apresentaram malformações congênitas do sistema nervoso central. Conclusão: Constatou-se alterações nas habilidades de linguagem na maioria dos sujeitos com craniossinostoses sindrômicas, bem como o baixo desempenho cognitivo.

Minor Suture Fusion in Syndromic Craniosynostosis.

BACKGROUND: Infants with craniofacial dysostosis syndromes may present with midface abnormalities but without major (calvarial) suture synostosis and head shape anomalies. Delayed presentation of their calvarial phenotype is known as progressive postnatal craniosynostosis. Minor sutures/synchondroses are continuations of major sutures toward and within the skull base. The authors hypothesized that minor suture synostosis is present in infants with syndromic, progressive postnatal craniosynostosis, and is associated with major suture synostosis. METHODS: The authors performed a two-institution review of infants (<1 year) with syndromic craniosynostosis and available computed tomographic scans. Major (i.e., metopic, sagittal, coronal, and lambdoid) and minor suture/synchondrosis fusion was determined by two craniofacial surgeons and one radiologist using Mimics or Radiant software. RESULTS: Seventy-three patients with 84 scans were included. Those with FGFR2 mutations were more likely to lack any major suture fusion (OR, 19.0; p = 0.044). Minor suture fusion occurred more often in the posterior branch of the coronal arch (OR, 3.33; p < 0.001), squamosal arch (OR, 7.32; p < 0.001), and posterior intraoccipital synchondroses (OR, 15.84; p < 0.001), among FGFR2 versus other patients. Patients (n = 9) with multiple scans showed a pattern of minor suture fusion followed by increased minor and major suture synostosis. Over 84 percent of FGFR2 patients had minor suture fusion; however, six (13 percent) were identified with isolated major suture synostosis. CONCLUSIONS: Minor suture fusion occurs in most patients with FGFR2-related craniofacial dysostosis. Syndromic patients with patent calvarial sutures should be investigated for minor suture involvement. These data have important implications for the pathophysiology of skull growth and development in this select group of patients. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Findings, phenotypes, and outcomes in Freeman-Sheldon and Sheldon-Hall syndromes and distal arthrogryposis types 1 and 3: protocol for systematic review and patient-level data meta-analysis.

BACKGROUND: Freeman-Sheldon and Sheldon-Hall syndromes (FSS and SHS) and distal arthrogryposis types 1 and 3 (DA1 and DA3) are rare, often confused, congenital syndromes. Few studies exist. With reported diagnosis unreliable, it would be scientifically inappropriate to consider articles describing FSS, SHS, DA1, or DA3, unless diagnoses were independently verified, rendering conventional systematic review and meta-analysis methodology inappropriate and necessitating patient-level data analysis (PROSPERO: CRD42015024740). METHODS/DESIGN: As part of a clinical practise guideline development process, we evaluate (1) diagnostic accuracy from 1938-2017, using the Stevenson criteria; (2) the most common physical findings, possible frequency clusters, and complications of physical findings amongst patients with FSS; and (3) treatment types and outcomes. All papers reporting diagnosis of FSS, SHS, DA1, and DA3 are included in searching PubMed and Google Scholar from December 2014 to July 2015 and again before final analyses. Patients with FSS are divided into four phenotype-defined sub-types; all patients are grouped by published diagnosis and medical speciality. Significance of physical findings and historical data is evaluated by chi-square. Associations of physical findings and history with diagnosis and treatment outcome are evaluated by Pearson correlation and linear regression analysis. Two-tailed alpha level of 0.05 is used throughout. DISCUSSION: The need for detailed patient-level data extraction may limit the types of articles included and questions able to be answered. For treatment and psychosocial health outcomes, we anticipate enhanced difficulties, which may limit significance, power, and results' usability. We hope to outline knowledge gaps and prioritise areas for clinical investigation. SYSTEMATIC REVIEW REGISTRATION NUMBER: CRD42015024740 Universal Trial Number: U1111-1172-4670.

Aberrant facial flushing following monobloc fronto-facial distraction.

BACKGROUND: Patients with syndromic forms of craniosynostosis may experience functional problems such as raised intracranial pressure, proptosis, obstructive sleep apnoea and failure to thrive. The monobloc fronto-facial advancement with osteogenic distraction is increasingly used to correct these functional problems in one procedure as well as improve appearance. The authors report the phenomenon of post operative aberrant facial flushing - an unusual and previously unreported complication of the procedure. METHODS: The case notes of 80 consecutive patients undergoing fronto-facial advancement by distraction using the rigid external distraction device (RED) were reviewed for features of aberrant facial flushing. RESULTS: Four out of eighty individuals developed facial flushing after monobloc fronto-facial distraction using the rigid external distractor (RED) frame. All were female with Crouzon or Pfeiffer syndromes causing the severe functional problems for which they underwent the surgery. They were aged 6-8 years. Following removal of the frame, they developed intermittent but severe facial flushing. The flushing spontaneously settled in three patients after up to four years but persists in the other child seven years after her surgery. CONCLUSION: Aberrant facial flushing is a rare but significant complication of monobloc fronto-facial surgery. It occurred in 4 of our 80 (5%) patients. The skull base osteotomies essential for the procedure are made anterior to the pterygopalatine ganglion and it is our contention that damage from these was responsible for a neuropraxia of its efferent nerve branches. A review of the autonomic control of the facial vascular system suggests that the phenomenon is due to an unequal process of recovery that leaves the cutaneous vasodilating parasympathetic or beta-adrenergic innervation relatively unopposed - a situation that persists until with time a normal balance of autonomic input is achieved.

Crouzon Syndrome: Relationship of Eye Movements to Pattern Strabismus.

PURPOSE: To characterize conjugate eye movements in Crouzon syndrome (CS) patients with and without strabismus. METHODS: Smooth pursuit, saccades, horizontal optokinetic nystagmus (OKN), and horizontal vestibulo-ocular reflex (VOR) were recorded using binocular video-oculography (VOG) in 10 children with CS (5 orthotropic, 5 strabismic) and 12 age-matched controls. Hess-Lancaster plots were generated from Orbit 1.8 using rectus muscle pulley locations from computed tomography imaging. Two-dimensional eye scan paths from VOG recordings were compared with the Hess-Lancaster plots. RESULTS: Targeted saccades were normometric on average but variable, and followed the main sequence in both CS groups. Smooth pursuit gains were normal for both CS groups; however, SP gains of the fixating eye in subjects with strabismus were significantly lower. Optokinetic nystagmus gains were reduced in both CS groups (P < 0.02) but were lower in subjects with strabismus. Shifting misalignments of binocular eye position in primary and eccentric gazes were associated with reduction in OKN gain in both CS groups. Vestibulo-ocular reflex gains for both CS groups were largely normal despite the presence of an off-axis vertical component. CONCLUSIONS: Normal gains for saccades and smooth pursuit in CS patients with strabismus are consistent with accurate execution of both movements despite extorsion of the globe. Vestibulo-ocular reflex in CS patients with strabismus had an off-axis vertical component consistent with extorted muscle pulleys. Optokinetic nystagmus is reduced in CS without strabismus owing to binocular position disparities and in CS with strabismus is likely due to cortical suppression associated with cross-axis orientation and exotropia.

The embryonic myosin R672C mutation that underlies Freeman-Sheldon syndrome impairs cross-bridge detachment and cycling in adult skeletal muscle.

Distal arthrogryposis is the most common known heritable cause of congenital contractures (e.g. clubfoot) and results from mutations in genes that encode proteins of the contractile complex of skeletal muscle cells. Mutations are most frequently found in MYH3 and are predicted to impair the function of embryonic myosin. We measured the contractile properties of individual skeletal muscle cells and the activation and relaxation kinetics of isolated myofibrils from two adult individuals with an R672C substitution in embryonic myosin and distal arthrogryposis syndrome 2A (DA2A) or Freeman-Sheldon syndrome. In R672C-containing muscle cells, we observed reduced specific force, a prolonged time to relaxation and incomplete relaxation (elevated residual force). In R672C-containing muscle myofibrils, the initial, slower phase of relaxation had a longer duration and slower rate, and time to complete relaxation was greatly prolonged. These observations can be collectively explained by a small subpopulation of myosin cross-bridges with greatly reduced detachment kinetics, resulting in a slower and less complete deactivation of thin filaments at the end of contractions. These findings have important implications for selecting and testing directed therapeutic options for persons with DA2A and perhaps congenital contractures in general.

Mandibular asymmetry in patients with the crouzon or apert syndrome.

The aim of this study was to describe directional and fluctuating mandibular asymmetry over time in children with Crouzon or Apert syndrome. Mandibular asymmetry of children between 7.5 and 14 years of age with Crouzon syndrome (n = 35) and Apert syndrome (n = 24) were compared with controls (n = 327). From panoramic radiographs, mandibular directional and fluctuating asymmetry was determined for the three groups. Multilevel statistical techniques were used to describe mandibular asymmetry changes over time. Patients with Crouzon and Apert syndromes showed statistically significant more fluctuating asymmetry for mandibular measures than did controls. Between the Crouzon and Apert syndromes groups, no statistical differences were found in directional and fluctuating asymmetry. The control group showed statistically significantly more directional asymmetry than did patients with Crouzon or Apert syndrome. The controls showed no change over time for the directional asymmetry of condylar-ramal height; however, the directional asymmetry of the gonial angle increased. Patients with Crouzon syndrome showed side dominance for only condylar-ramal height; whereas, patients with Apert syndrome did not show dominance for any of the measurements. Apert and Crouzon syndromes showed developmental instability, in contrast to the controls. No statistically significant longitudinal differences were found for either the directional or the fluctuating asymmetry between Crouzon and Apert syndromes. Findings for fluctuating and directional asymmetry for both syndromes may indicate an inability to cope with genetic and environmental stress during development and treatment, compared with untreated nonsyndromic individuals.

Earlier evidence of spheno-occipital synchondrosis fusion correlates with severity of midface hypoplasia in patients with syndromic craniosynostosis.

BACKGROUND: The spheno-occipital synchondrosis is an important driver of facial and cranial base growth. The current study characterizes its fusion in patients with Apert, Crouzon, and Pfeiffer syndromes and correlates early fusion with the presence, and degree, of midface hypoplasia. METHODS: A retrospective case-control study was performed of all syndromic patients treated between 1996 and 2012. Case computed tomographic scans and age- and sex-matched control scans were analyzed as demonstrating either open, partially fused, or completely fused synchondroses, and patient age at each scan was recorded. Midface hypoplasia as determined by sella-nasion-A point angle measurement at the time of midface surgery was correlated to fusion status. RESULTS: Fifty-four patients with 206 computed tomographic scans met inclusion criteria. Two hundred six age- and sex-matched control scans were also identified. Average age at computed tomographic scanning was 6.1 years. The earliest ages of partial and complete fusion were 1.1 and 7.0 years, respectively, among cases; and 6.2 and 12.7 years, respectively, among controls. The odds of synchondrosis fusion in case computed tomographic scans was 66.0 times that of controls (95 percent CI, 9.2 to 475.5 times that of controls; p < 0.000001). Average age of synchondrosis fusion was 3.5 years (range, 0.5 to 6.0 years). Average sella-nasion-A point angle at the time of midface surgery was 67.5 degrees (range, 58 to 76 degrees), with a positive correlation between earlier age of fusion and more severe midface hypoplasia (p = 0.028). CONCLUSIONS: The spheno-occipital synchondrosis fuses earlier in syndromic patients compared with age-matched controls. Moreover, there is a positive correlation between earlier fusion and degree of midface hypoplasia, although definitive causality cannot be concluded. This is the first study to demonstrate such a correlation in human subjects. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.

The spheno-occipital synchondrosis fuses prematurely in patients with Crouzon syndrome and midface hypoplasia compared with age- and gender-matched controls.

PURPOSE: Premature closure of the spheno-occipital synchondrosis (SOS) has been associated with midface hypoplasia in animal models and patients with specific forms of syndromic craniosynostosis. The present study aimed to characterize SOS fusion in patients with Crouzon syndrome. PATIENTS AND METHODS: A case-control study was performed in patients with Crouzon syndrome treated at the Children's Hospital of Philadelphia from 1984 to 2012. The cases included patients with Crouzon syndrome and at least 1 high-quality computed tomography (CT) scan in which SOS patency could be assessed. Age- and gender-matched control CT scans were identified for comparison. The patient age at the CT scan was evaluated as the predictor, with SOS patency identified as the outcome variable. Three independent reviewers with high inter-rater reliability graded the SOS patency as open, partially fused, or completely fused. The Wilcoxon rank sum test was used to compare the Crouzon group and the controls. RESULTS: During the study period, 30 patients were identified with Crouzon syndrome. A total of 24 patients, all with midface hypoplasia and with 112 cranial CT scans, met the inclusion criteria. Accordingly, 112 age- and gender-matched control CT scans were assessed. No patient in the control group had midface hypoplasia. Within the Crouzon group, the average age at complete closure (14.0 ± 3.4 years) evident on the CT scan was significantly younger than that in the control group (16.6 ± 2.2 years; P = .0152). The average age when the scans showed complete patency of the SOS in the Crouzon group (1.3 ± 1.1 years) was significantly younger than that in the control group (3.2 ± 2.3 years; P = .0001). CONCLUSIONS: The SOS closes significantly earlier in patients with Crouzon syndrome compared with age- and gender-matched controls. The strong statistical correlation supports premature closure of the SOS as a possible mechanistic contributor to midface hypoplasia.

Patient-reported quality of life in highest-functioning Apert and Crouzon syndromes: a comparative study.

BACKGROUND: Crouzon and Apert syndromes are the most common syndromic forms of craniofacial dysostosis. Apert syndrome has a broad clinical spectrum, including complex craniofacial involvement, as well as limiting deformities of the hands, feet, and other joints that require multiple surgical procedures when compared with Crouzon syndrome, which is generally less severe. The authors hypothesized that the quality of life of Apert syndrome patients is inferior to that of Crouzon syndrome patients. METHODS: The quality of life of Apert (n = 8) and Crouzon (n = 12) syndrome patients was assessed using the World Health Organization Quality of Life-100 questionnaire. The Mann-Whitney test was used to compare the quality-of-life scores between Apert and Crouzon patients. Values were considered significant for a confidence interval of 95 percent (p < 0.05). RESULTS: Apert patients showed an overall higher (score > 60 percent) quality of life in most World Health Organization Quality of Life-100 facets (68 percent) and domains (83.33 percent), with significance (p < 0.05) in three facets (energy and fatigue, mobility, and environment in the home), compared with Crouzon patients. CONCLUSION: Contrary to the authors' initial hypothesis, both the highest-functioning Apert patients and the Crouzon patients presented a satisfactory quality of life, demonstrating that these syndromic patients had acquired the necessary repertoire to manage the adverse daily situations of their lives.

Crouzon syndrome: relationship of rectus muscle pulley location to pattern strabismus.

PURPOSE: Investigate the relationship between the extorsion of the rectus muscle pulleys and the V-pattern exotropia and "overelevation in adduction" observed in Crouzon syndrome. METHODS: Twenty children with Crouzon syndrome had assessment of eye alignment. The horizontal and vertical positions of the four rectus muscle pulleys were estimated from coronal CT images. Eye alignment was simulated in Orbit 1.8 software by shifting the corresponding location of the rectus muscle pulley array. RESULTS: Eleven of the 20 patients had a V-pattern exotropia with displacements of each rectus muscle pulley ranging from 2 to 7 mm. The remaining nine patients were orthotropic with <2 mm displacement of the rectus muscle pulleys. Simulated displacements (>2 mm) of either the horizontal or vertical rectus muscle pulleys produced a similar strabismus pattern. The amount of V-pattern exotropia observed clinically was highly correlated with the amount predicted by pulley displacements in Orbit 1.8 (r(2) = 0.63; P < 0.0001). The displacement of vertical and horizontal rectus muscle pairs was significantly higher for patients having overelevation in adduction. CONCLUSIONS: Rotation of the four rectus muscle pulleys relative to the corresponding rotation planes of the globe changes the direction and magnitude of their active and passive pulling forces in a gaze-dependent manner. Extorsion of the horizontal and vertical rectus muscle pulleys in Orbit 1.8 reproduces the pattern strabismus observed in Crouzon syndrome. The high correlation between the predicted magnitude of the V-pattern exotropia and observed exotropia indicates that extorsion of the rectus muscle pulleys primarily accounts for the pattern strabismus.

Dental maturation in children with the syndrome of crouzon and apert.

Purpose : Developing teeth are used to assess maturity and estimate age in a number of disciplines. The purpose of this investigation was to study the dental maturation in children with Crouzon or Apert syndrome compared with nonsyndromic controls. Patients and Methods : Records of 40 children with Crouzon syndrome (18 boys and 22 girls, aged 4.0 to 17.9 years) and 28 children with Apert syndrome (10 boys and 18 girls, aged 3.9 to 15.1 years) were referred to the Department of Orthodontics, Cleft Palate Team and Craniofacial Team, Erasmus MC-Sophia. Data from syndromic children were compared with data from 451 nonsyndromic children (225 boys and 226 girls, aged 2.9 to 16.9 years). From panoramic radiographs, dental maturation was determined for patients with Crouzon and Apert syndromes and compared with data collected from control children. Logistic functions were constructed for dental maturation over time for syndromes and gender. Results : Statistically significant gender differences in dental maturation scores were found for girls with Crouzon (P < .05) and Apert syndrome (P < .05). Patients with Apert syndrome demonstrated a significantly delayed dental maturation (P < .05), while patients with Crouzon syndrome showed a nonsignificant delay. Conclusions : Dental maturation in patients with Apert syndrome was more delayed than in patients with Crouzon syndrome. The delay of tooth formation in patients with Crouzon or Apert syndrome suggests a possible common genetic association.