Revisiting Crouzon syndrome: reviewing the background and management of a multifaceted disease

Adenoidectomy in a child with Crouzon syndrome complicated with severe obstructive sleep apnea: Case report and review of literature

RATIONALE

Crouzon syndrome is an extremely rare craniofacial dysplasia, which is mainly caused by the early ossification and closure of the coronal suture of the skull. Craniofacial deformities can cause stenosis of the nasal cavity and posterior nasal meatus, resulting in sleep apnea.

PATIENT CONCERNS

A 9-year-old boy with sleep snoring for 6 years, progressive aggravation in the past 1 month and accompanied by apnea during sleep.

DIAGNOSES

This case was diagnosed with Crouzon syndrome complicated with severe obstructive sleep apnea and severe hypoxemia.

INTERVENTIONS

After adenoidectomy, he was admitted to the pediatric intensive care unit with ventilator-assisted respiration. During this period, the blood oxygen saturation fluctuated greatly. After trying to extubate, the blood oxygen was difficult to maintain and had to be intubated again. After active treatment, extubation was successful.

OUTCOMES

The wound of nasopharynx recovered well and the sleep state was significantly improved 3 months postoperation.

LESSONS

It is suggested that the time of ventilator-assisted breathing should be prolonged and the perioperative airway management should be strengthened in order to reduce the risk of postoperative complications.

Crouzon Syndrome Spanning Three Generations: Advances in the Treatment of Syndromic Midface Deficiency

Background

Crouzon syndrome is an autosomal dominant genetic disorder characterized by craniosynostosis, midface retrusion, and exophthalmos. Over the past century, the treatment of craniofacial disorders like Crouzon syndrome has evolved significantly.

Methods

An institutional review board-approved retrospective study was conducted to ascertain the treatment of three individuals with Crouzon syndrome from one family, complemented with a series of literature searches to examine the evolution of craniofacial surgical history.

Results

Dr. David Williams Cheever developed the Le Fort I level to correct malocclusion, maxillomandibular malformations, and midface hypoplasia. Later, Dr. Paul Tessier introduced the Le Fort II and III osteotomies to treat syndromic midface hypoplasia. In 1978, Dr. Fernando Ortiz-Monasterio and Dr. Antonio Fuente del Campo published the first series of monobloc osteotomies, allowing for simultaneous correction of supraorbital and midface malformations, although complicated by blood loss and high infection rates. In 1992, McCarthy et al introduced the concept of gradual distraction to the craniofacial skeleton. In 1995, Polley et al performed the first monobloc advancement using external distraction. Subsequently, in 1997, Polley and Figueroa introduced a rigid external distraction device with multiple vector control to manage severe cleft maxillary hypoplasia. The technique was further refined and applied to treat syndromic midface hypoplasia, reducing complication rates. Currently, either external or internal distraction approaches are used to safely treat this challenging group of patients.

Conclusion

The treatment of syndromic midface deficiency has significantly evolved over the past 50 years, as evidenced by this report of three generations of Crouzon syndrome.

Jaw size variation is associated with a novel craniofacial function for galanin receptor 2 in an adaptive radiation of pupfishes

Understanding the genetic basis of novel adaptations in new species is a fundamental question in biology. Here we demonstrate a new role for galr2 in vertebrate craniofacial development using an adaptive radiation of trophic specialist pupfishes endemic to San Salvador Island, Bahamas. We confirmed the loss of a putative Sry transcription factor binding site upstream of galr2 in scale-eating pupfish and found significant spatial differences in galr2 expression among pupfish species in Meckel's cartilage using in situ hybridization chain reaction (HCR). We then experimentally demonstrated a novel role for Galr2 in craniofacial development by exposing embryos to Garl2-inhibiting drugs. Galr2-inhibition reduced Meckel's cartilage length and increased chondrocyte density in both trophic specialists but not in the generalist genetic background. We propose a mechanism for jaw elongation in scale-eaters based on the reduced expression of galr2 due to the loss of a putative Sry binding site. Fewer Galr2 receptors in the scale-eater Meckel's cartilage may result in their enlarged jaw lengths as adults by limiting opportunities for a circulating Galr2 agonist to bind to these receptors during development. Our findings illustrate the growing utility of linking candidate adaptive SNPs in non-model systems with highly divergent phenotypes to novel vertebrate gene functions.

Mobility Assessment Using Multi-Positional MRI in Children with Cranio-Vertebral Junction Anomalies

OBJECTIVE

This study aimed to assess the relevance of using multi-positional MRI (mMRI) to identify cranio-vertebral junction (CVJ) instability in pediatric patients with CVJ anomalies while determining objective mMRI criteria to detect this condition.

MATERIAL AND METHODS

Data from children with CVJ anomalies who underwent a mMRI between 2017 and 2021 were retrospectively reviewed. Mobility assessment using mMRI involved: (1) morphometric analysis using hierarchical clustering on principal component analysis (HCPCA) to identify clusters of patients by considering their mobility similarities, assessed through delta (Δ) values of occipito-cervical parameters measured on mMRI; and (2) morphological analysis based on dynamic geometric CVJ models and analysis of displacement vectors between flexion and extension. Receiver operating characteristics (ROC) curves were generated for occipito-cervical parameters to establish instability cut-off values. (3) Additionally, an anatomical qualitative analysis of the CVJ was performed to identify morphological criteria of instability.

RESULTS

Forty-seven patients with CVJ anomalies were included (26 females, 21 males; mean age: 10.2 years [3-18]). HCPCA identified 2 clusters: cluster №1 (stable patients, n = 39) and cluster №2 (unstable patients, n = 8). ΔpB-C2 (pB-C2 line delta) at ≥2.5 mm (AUC 0.98) and ΔBAI (Basion-axis Interval delta) ≥ 3 mm (AUC 0.97) predicted instability with 88% sensibility and 95% specificity and 88% sensitivity and 85% specificity, respectively. Geometric CVJ shape analysis differentiated patients along a continuum, from a low to a high CVJ motion that was characterized by a subluxation of C1 in the anterior direction. Qualitative analysis found correlations between instability and C2 anomalies, including fusions with C3 (body p = 0.032; posterior arch p = 0.045; inferior articular facets p = 0.012; lateral mass p = 0.029).

CONCLUSIONS

We identified a cluster of pediatric patients with CVJ instability among a cohort of CVJ anomalies that were characterized by morphometric parameters with corresponding cut-off values that could serve as objective mMRI criteria. These findings warrant further validation through prospective case-control studies.

Jaw size variation is associated with a novel craniofacial function for galanin receptor 2 in an adaptive radiation of pupfishes

Understanding the genetic basis of novel adaptations in new species is a fundamental question in biology that also provides an opportunity to uncover new genes and regulatory networks with potential clinical relevance. Here we demonstrate a new role for galr2 in vertebrate craniofacial development using an adaptive radiation of trophic specialist pupfishes endemic to San Salvador Island in the Bahamas. We confirmed the loss of a putative Sry transcription factor binding site in the upstream region of galr2 in scale-eating pupfish and found significant spatial differences in galr2 expression among pupfish species in Meckel's cartilage and premaxilla using in situ hybridization chain reaction (HCR). We then experimentally demonstrated a novel function for Galr2 in craniofacial development and jaw elongation by exposing embryos to drugs that inhibit Galr2 activity. Galr2-inhibition reduced Meckel's cartilage length and increased chondrocyte density in both trophic specialists but not in the generalist genetic background. We propose a mechanism for jaw elongation in scale-eaters based on the reduced expression of galr2 due to the loss of a putative Sry binding site. Fewer Galr2 receptors in the scale-eater Meckel's cartilage may result in their enlarged jaw lengths as adults by limiting opportunities for a postulated Galr2 agonist to bind to these receptors during development. Our findings illustrate the growing utility of linking candidate adaptive SNPs in non-model systems with highly divergent phenotypes to novel vertebrate gene functions.

Mysterious Bilateral Foot Pain in a Child With Crouzon Syndrome

Crouzon syndrome (CS) is a rare autosomal dominant disorder that requires care from a multidisciplinary team and early surgical management to minimize complications. Despite the shared similarities across craniosynostoses, CS can be differentiated by the presence of normal bone development of the hands and feet and hypertelorism (large distance between the eyes). Other common features include midface hypoplasia, shallow orbits, ocular proptosis, and dental abnormalities including possible bifid uvula or V-shaped maxillary arch. In this report, we present a case of prolonged foot pain in a four-year and two-month-old boy with CS; we also engage in a brief review of the literature. The patient's physical exam and laboratory work were unremarkable on the initial presentation. Radiographic films showed signs of potential demineralization of bone tissue. He was prescribed calcium and vitamin D supplementation with complete resolution of his symptoms at the three-month follow-up visit.

Surgical treatment of bony nasal airway stenosis in a patient with adult Crouzon’s syndrome

Crouzon’s syndrome is associated with the respiratory impairment of the upper airway due to mid-facial hypoplasia. We managed an adult Crouzon patient who wanted us to treat his choanal and nasopharyngeal stenosis for obstructive sleep apnea relief and tracheostomy tube extubation. We drilled out the abnormal maxillary bone and created a new nasal passage to the pharynx. Epithelialization of the new nasal cavity was completed within a month, and the patient was able to breathe through the nose and his sense of smell improved somewhat after the surgery. Although the apnea-hypopnea index had decreased, sleep apnea remained.

Rare Genetic Syndromes and Oral Anomalies: A Review of the Literature and Case Series with a New Classification Proposal

Rare genetic syndromes, conditions with a global average prevalence of 40 cases/100,000 people, are associated with anatomical, physiological, and neurological anomalies that may affect different body districts, including the oral district. So far, no classification of oral abnormalities in rare genetic syndromes is present in the literature. The aim of this narrative review is to analyze literature on rare genetic syndromes affecting dento-oro-maxillofacial structures (teeth, maxillary bones, oral soft tissues, or mixed) and to propose a classification according to the detected oral abnormalities. In addition, five significant cases of rare genetic syndromes are presented. The Scale for the Assessment of Narrative Review Articles (SANRA) was followed for this review. From 674 papers obtained through PubMed search, 351 were selected. Sixty-two rare genetic syndromes involving oral manifestations were found and classified. The proposed classification aims to help the clinician to easily understand which dento-oro-maxillofacial findings might be expected in the presence of each rare genetic syndrome. This immediate framework may both help in the diagnosis of dento-oro-maxillofacial anomalies related to the underlying pathology as well as facilitate the drafting of treatment plans with the involvement of a multidisciplinary team.

Comprehensive management of Crouzon syndrome: A case report with three-year follow-up

Crouzon syndrome is one of the most common craniosynostosis facial syndromes caused by a mutation in the fibroblast growth factor receptor 2 (FGFR2) gene. Less commonly, there is a mutation of the FGFR3 gene which results in Crouzon syndrome syndrome with acanthosis nigricans. It involves the premature fusion of sutures of the cranial vault, base, orbital and maxillary region. The clinical presentation of this congenital deformity depends on the pattern and timing of sutural fusion. The present report describes the features and management of this syndrome in an 18-year-old woman. The patient presented with a hypoplastic maxilla, deficient midface, exorbitism due to shallow orbits, severe crowding and bilateral crossbite. A multidisciplinary approach involving orthodontics and surgical intervention with distraction osteogenesis brought about marked improvement in the facial profile, occlusion and upper airway. The aesthetics and function were greatly enhanced, and the results were found to be stable at the end of three years.

Craniosynostosis: Neonatal Perspectives

Craniosynostosis is the premature fusion of 1 or more sutures that normally separate the bony plates of an infant's skull and occurs in about 1 in 2,000 to 2,500 live births. Primary or congenital craniosynostoses represent the majority of cases and consist of single-suture and multisuture synostoses. Multisuture synostoses are typically associated with distinct craniofacial syndromes, including Muenke syndrome, Apert syndrome, Crouzon syndrome, and Pfeiffer syndrome, and are thus categorized under syndromic craniosynostoses. Secondary causes of craniosynostoses include metabolic or hematologic disorders that affect bone metabolism and typically present much later than primary synostoses. The severity of the deformity and the presence of increased intracranial pressure dictate the need for early surgical intervention, prompting the importance of early recognition and timely referral. Infants with craniosynostosis are also at increased risk for neurodevelopmental impairment and thus require close follow-up and monitoring. The early recognition and referral of craniosynostosis is imperative for the optimization of management and minimization of potential neurologic impairments that may develop.

Long Term Speech Outcomes Following Midface Advancement in Syndromic Craniosynostosis

Midface advancement by distraction osteogenesis (DO) is commonly performed in patients with craniosynostosis for indications including midface hypoplasia, exorbitism, obstructive sleep apnea, class III malocclusion, and overall aesthetic facial deficiency. There is evidence to suggest that maxillary LeFort I advancement increases the risk of velopharyngeal dysfunction in the cleft palate population, yet few studies have investigated changes in speech following LeFort III or monobloc midface advancement in patients with syndromic craniosynostosis. The purpose of this study was to examine the effect of midface DO on speech as indicated by the Pittsburgh Weighted Speech Score in patients with Apert, Crouzon, and Pfeiffer Syndrome. Among 73 midface advancement cases performed during the study period, 19 cases met inclusion criteria. Overall, the highest post-advancement Pittsburgh Weighted Speech Score (PWSS) was significantly higher than the pre-advancement PWSS (0.52 versus 2.42, P = 0.01), indicating an acute worsening of VPI post-advancement. Specifically, the PWSS components nasal emission and nasality were significantly higher post-advancement than pre-advancement (nasal emission: 1.16 versus 0.21, P = 0.02) (nasality: 0.68 versus 0.05, P = 0.04). However, there was no significant difference between pre-advancement PWSS and the latest post-advancement PWSS (P = 0.31). Midface distraction is associated with an acute worsening of VPI post-operatively that is followed by improvement, and often resolution over time. Future work with additional patient accrual is needed to determine the effect of different advancement procedures and syndromes on VPI rates and profundity.

Surgical Correction of Severe Kyphoscoliosis Associated with Crouzon Syndrome with Serious Postoperative Respiratory Problems: A Case Report

CASE

A 12-year-old girl with Crouzon syndrome presented to our hospital with scoliosis (114°) and kyphosis from T8 to T12 (138°). After she had been in halo-gravity traction for 2 weeks, we performed posterior correction and fusion surgery from T3 to L3, with a posterior vertebral column resection of T10. She experienced postoperative respiratory failure and remained on a ventilator for 4 weeks. With rehabilitation, the respiratory function had recovered by postoperative week 8. At the 2-year follow-up, there was no loss of correction or any other complication.

CONCLUSION

Serious perioperative respiratory complications may occur when a patient with Crouzon syndrome is treated surgically.

Improvement of Color Vision Following Posterior Cranial Vault Distraction for Crouzon Syndrome

Crouzon syndrome (CS) is one of the craniosynostosis syndromes that leads to early fusion of cranial sutures and increased intracranial pressure. Intracranial hypertension is a serious complication that may lead to vision loss and cognitive impairment. Early detection and management are necessary to prevent complications. The authors present a patient with CS who underwent posterior cranial vault reconstruction with internal distraction after multiple episodes of headache and papilledema. The patient was unaware of any loss of color vision before the surgery; however, he noted an improvement in his color vision after the surgery. Color vision deficits may be an early sign of intracranial hypertension and finding these deficits using noninvasive testing methods may be an indication for early intervention.

C-type natriuretic peptide analog treatment of craniosynostosis in a Crouzon syndrome mouse model

Activating mutations of fibroblast growth factor receptors (FGFRs) are a major cause of skeletal dysplasias, and thus they are potential targets for pharmaceutical intervention. BMN 111, a C-type natriuretic peptide analog, inhibits FGFR signaling at the level of the RAF1 kinase through natriuretic peptide receptor 2 (NPR2) and has been shown to lengthen the long bones and improve skull morphology in the Fgfr3Y367C/+ thanatophoric dysplasia mouse model. Here we report the effects of BMN 111 in treating craniosynostosis and aberrant skull morphology in the Fgfr2cC342Y/+ Crouzon syndrome mouse model. We first demonstrated that NPR2 is expressed in the murine coronal suture and spheno-occipital synchondrosis in the newborn period. We then gave Fgfr2cC342Y/+ and Fgfr2c+/+ (WT) mice once-daily injections of either vehicle or reported therapeutic levels of BMN 111 between post-natal days 3 and 31. Changes in skeletal morphology, including suture patency, skull dimensions, and long bone length, were assessed by micro-computed tomography. Although BMN 111 treatment significantly increased long bone growth in both WT and mutant mice, skull dimensions and suture patency generally were not significantly affected. A small but significant increase in the relative length of the anterior cranial base was observed. Our results indicate that the differential effects of BMN 111 in treating various skeletal dysplasias may depend on the process of bone formation targeted (endochondral or intramembranous), the specific FGFR mutated, and/or the specific signaling pathway changes due to a given mutation.

Crouzon Syndrome: a Comprehensive Review

Crouzon syndrome is a rare genetic disorder with autosomal dominant inheritance. The underlying pathological process is premature synostosis of the cranial sutures with subsequent phenotypic alterations of the affected person. A review of the literature has been conducted in order to resume the overall characteristics of Crouzon syndrome such as craniomaxillofacial malformations, clinical features, dentoalveolar characteristics, aesthetic impairments, and psychological background, as well as, the different therapeutic procedures, which combine surgical and orthodontic interventions. Facial and functional malformations in individuals with Crouzon syndrome could be significantly improved after a series of surgical and orthodontic procedures in almost all cases. A multidisciplinary treatment approach would provide the best outcomes in affected patients.

Extensive phenotyping of the orofacial and dental complex in Crouzon syndrome

OBJECTIVES

Fibroblast growth factor receptor 2 (FGFR2) ^C342Y/+ mutation is a known cause of Crouzon syndrome that is characterised by craniosynostosis and midfacial hypoplasia. Our aim was to conduct extensive phenotyping of the maxillary, mandibular and dental morphology associated with this mutation.

MATERIALS AND METHODS

Morphometric data were obtained from 40 mice, representing two genotypes (Crouzon and wild-type) and two sexes (males and females) (n=10 in each group). Dental analysis further categorised the first molars into the two jaws (maxillary and mandibular) (n=20 in each group). Maxillary, mandibular and dental morphology was compared by analysing 23 linear landmark-based dimensions in three-dimensional micro-computed tomography reconstructions.

RESULTS

Compared with wild-type, Crouzon (FGFR2^C342Y/+) maxillae were significantly shorter in maximum height, anterior and posterior lengths and middle width, but larger in posterior width (p<0.05 for height; p<0.001 for other comparisons). In the Crouzon mandible, the ascending and descending heights, effective and mandibular lengths, and intercoronoid and intercondylar widths were significantly shorter, whereas intergonial width was larger (p<0.01 for intercondylar width; p<0.001 for other comparisons). Crouzon teeth were significantly smaller mesiodistally, but larger in crown height (p<0.001 for each comparison). All Crouzon mice presented with bifid mandibular condyles and a quarter presented with expansive bone lesions in the mandibular incisor alveolus.

CONCLUSIONS

Our findings of hypoplasia in all three planes in Crouzon maxillae and mandibles, together with the presence of bifid mandibular condyles and expansive bone lesions, may be relevant to maxillofacial surgery and orthodontics. Beyond skeletal effects, the FGFR2^C342Y/+ mutation is now implicated in affecting tooth development. This study's skeletal phenomics data also provides baseline data against which the effect of various treatments can now be assessed.

Analysis of the Fgfr2C342Y mouse model shows condensation defects due to misregulation of Sox9 expression in prechondrocytic mesenchyme

Syndromic craniosynostosis caused by mutations in FGFR2 is characterised by developmental pathology in both endochondral and membranous skeletogenesis. Detailed phenotypic characterisation of features in the membranous calvarium, the endochondral cranial base and other structures in the axial and appendicular skeleton has not been performed at embryonic stages. We investigated bone development in the Crouzon mouse model (Fgfr2^C342Y) at pre- and post-ossification stages to improve understanding of the underlying pathogenesis. Phenotypic analysis was performed by whole-mount skeletal staining (Alcian Blue/Alizarin Red) and histological staining of sections of CD1 wild-type (WT), Fgfr2^C342Y/+ heterozygous (HET) and Fgfr2^C342Y/C342Y homozygous (HOM) mouse embryos from embryonic day (E)12.5-E17.5 stages. Gene expression (Sox9, Shh, Fgf10 and Runx2) was studied by in situ hybridisation and protein expression (COL2A1) by immunohistochemistry. Our analysis has identified severely decreased osteogenesis in parts of the craniofacial skeleton together with increased chondrogenesis in parts of the endochondral and cartilaginous skeleton in HOM embryos. The Sox9 expression domain in tracheal and basi-cranial chondrocytic precursors at E13.5 in HOM embryos is increased and expanded, correlating with the phenotypic observations which suggest FGFR2 signalling regulates Sox9 expression. Combined with abnormal staining of type II collagen in pre-chondrocytic mesenchyme, this is indicative of a mesenchymal condensation defect. An expanded spectrum of phenotypic features observed in the Fgfr2^C342Y/C342Y mouse embryo paves the way towards better understanding the clinical attributes of human Crouzon-Pfeiffer syndrome. FGFR2 mutation results in impaired skeletogenesis; however, our findings suggest that many phenotypic aberrations stem from a primary failure of pre-chondrogenic/osteogenic mesenchymal condensation and link FGFR2 to SOX9, a principal regulator of skeletogenesis.

Mutation c.943G>T (p.Ala315Ser) in FGFR2 Causing a Mild Phenotype of Crouzon Craniofacial Dysostosis in a Three-Generation Family

Crouzon syndrome craniofacial dysostosis type I [OMIM 123500] is caused by mutations in the gene encoding fibroblast growth factor receptor-2 (FGFR2). An overlapping phenotype with Muenke and Crouzon syndrome with acanthosis nigricans (FGFR3 mutations) is known. The clinical diagnosis can be corroborated by molecular studies in about 80-90% of the cases. No clear genotype/phenotype correlation has been identified yet. Here, we describe a second family with a mild phenotype in which the FGFR2 mutation c.943G>T leading to the amino acid substitution p.Ala315Ser was detected. Five affected family members showed craniofacial dysostosis without overt craniosynostosis. They all had midface hypoplasia. Crouzonoid appearance with mild protrusion of bulbi was only apparent in our index patient as well as obstructive sleep apnea episodes leading to reduced oxygen saturation; therefore, surgical intervention was suggested. One other affected family member additionally had iris coloboma.

Selective mutation accumulation: a computational model of the paternal age effect

MOTIVATION

As the mean age of parenthood grows, the effect of parental age on genetic disease and child health becomes ever more important. A number of autosomal dominant disorders show a dramatic paternal age effect due to selfish mutations: substitutions that grant spermatogonial stem cells (SSCs) a selective advantage in the testes of the father, but have a deleterious effect in offspring. In this paper we present a computational technique to model the SSC niche in order to examine the phenomenon and draw conclusions across different genes and disorders.

RESULTS

We used a Markov chain to model the probabilities of mutation and positive selection with cell divisions. The model was fitted to available data on disease incidence and also mutation assays of sperm donors. Strength of selective advantage is presented for a range of disorders including Apert's syndrome and achondroplasia. Incidence of the diseases was predicted closely for most disorders and was heavily influenced by the site-specific mutation rate and the number of mutable alleles. The model also successfully predicted a stronger selective advantage for more strongly activating gain-of-function mutations within the same gene. Both positive selection and the rate of copy-error mutations are important in adequately explaining the paternal age effect.

AVAILABILITY AND IMPLEMENTATION

C ++/R source codes and documentation including compilation instructions are available under GNU license at https://github.com/anwala/NicheSimulation CONTACT: ewhel001@odu.eduSupplementary information: Supplementary data are available at Bioinformatics online.

Ultrasound and MR imaging findings in prenatal diagnosis of craniosynostosis syndromes

BACKGROUND

Craniosynostosis syndromes are uncommonly encountered in the prenatal period. Identification is challenging but important for family counseling and perinatal management.

OBJECTIVE

This series examines prenatal findings in craniosynostosis syndromes, comparing the complementary roles of US and MRI and emphasizing clues easily missed in the second trimester.

MATERIALS AND METHODS

Six prenatal cases evaluated from 2002 through 2011 were retrospectively reviewed. Referral history, gestational age, and sonographic and MRI findings were reviewed by three pediatric radiologists. Abnormalities of the calvarium, hands, feet, face, airway and central nervous system were compared between modalities.

RESULTS

The diagnosis was Apert syndrome in three, Pfeiffer syndrome in two and Carpenter syndrome in one. The gestational age at evaluation ranged from 21 to 33 weeks. All six were evaluated by MRI and US, with two undergoing repeat evaluation in the third trimester, yielding a total of eight MRIs and US exams. The referral history suggested cloverleaf skull in two cases but did not suggest craniosynostosis syndrome in any case. In four, the referral suggested central nervous system (CNS) findings that were not confirmed by MRI; additional CNS findings were discovered in the remaining two. In four cases, developing turricephaly resulted in a characteristic "lampshade" contour of the fetal head. Hypertelorism and proptosis were present in five, with proptosis better appreciated by MRI. Digit abnormalities were present in all, seen equally well by MRI and US. Lung abnormalities in the second trimester in one fetus resolved by the third trimester.

CONCLUSION

Prenatal diagnosis of craniosynostosis syndromes is difficult prior to the third trimester. MRI and US have complementary roles in evaluation of these patients.

Atypical post-adenoidectomy Grisel's syndrome in Crouzon child with kyphotic skull base

Crouzon syndrome is characterized by abnormal craniofacial growth due to craniosynostosis. Skull base may also be involved in the pattern of malformations. Grisel's syndrome, an inflammation-mediated atlanto-axial instability occurs rarely in children after adenoidectomy. We report a 9-year-old female Crouzon patient, without vertebral anomalies, who developed severe torticollis few days after adenoid curettage. A deformity of the skull base alone might have induced an irregular arrangement of the craniocervical junction elements, thus increasing the susceptibility to cervical spine complications.