Plea for systematic prenatal genes panel testing when facing isolated craniosynostosis on fetal imaging.

BACKGROUND: Prenatal diagnosis of craniosynostosis remains rare and challenging, easier in syndromes with craniosynostosis due to the association with other sonographic anomalies. Crouzon syndrome is the most frequent syndrome with craniosynostosis but is difficult to detect antenatally because of mild skull deformation without specific associated anomaly during gestation. CASE: This report presents the case of a fetus with Crouzon syndrome related to the variant c.1646A>C in exon 14 of the FGFR2 gene and presenting with apparently isolated scaphocephaly on fetal US. CONCLUSION: This observation supports the interest of systematic prenatal panel genes testing when facing an apparently isolated craniosynostosis diagnosed on fetal imaging, even if non-syndromic craniosynostosis are much more frequent in such situation. TEACHING POINTS: Syndromic craniosynostosis can appear as apparently isolated form on fetal imaging. Systematic prenatal panel genes testing can be contributive even when facing an apparently isolated craniosynostosis on fetal imaging.

Molecular Scalpels: The Future of Pediatric Craniofacial Surgery?

SUMMARY: CRISPR-Cas genome editing tools are among the most substantial advances in the life sciences in modern history. Single-dose gene therapies to correct pathogenic mutations have moved quickly from bench to bedside, with several therapeutics designed by CRISPR pioneers entering various stages of clinical investigation. Applications of these genetic technologies are poised to reshape the practice of both medicine and surgery. Many of the most morbid conditions treated by craniofacial surgeons are syndromic craniosynostoses caused by mutations in fibroblast growth factor receptor genes, including Apert, Pfeiffer, Crouzon, and Muenke syndromes. The fact that pathogenic mutations in these genes are recurrent in the majority of affected families presents a unique opportunity to develop "off-the-shelf" gene editing therapies to correct these mutations in affected children. The therapeutic potential of these interventions could reshape pediatric craniofacial surgery, potentially first eliminating the need for midface advancement procedures in affected children.

Crouzon syndrome complicated with binocular strabismus and extraocular muscle fibrosis: a case report.

BACKGROUND: Crouzon syndrome, a rare genetic disorder characterized by premature closure of coronal sutures, results in skull and facial deformities along with abnormal brain and ocular development. CASE PRESENTATION: Here, we report a case of a 27-year-old ethnic han male patient who presented with complex binocular strabismus secondary to Crouzon syndrome. At the time of surgery, extraocular muscles were found to be fibrotic and results of the pathological examination revealed degeneration of muscle fibers, which were replaced by adipose tissue. The entire exome sequencing DNA testing indicated that the patient and his father possessed the fibroblast growth factor receptor 2 (FGFR2) gene c.G812T:p.G271V heterozygous mutation. Binocular strabismus corrective surgery was performed in this patient with a satisfactory outcome. CONCLUSIONS: This case demonstrates that Crouzon syndrome patients can show an FGFR2 gene c.G812T:p.G271V mutation and display clinical symptoms such as extraocular muscle fibrosis, exotropia, exophthalmos, and a pointed head deformity.

Craniofacial characteristics in Crouzon's syndrome: A systematic review and meta-analysis.

The purpose of this meta-analysis was to strengthen the credibility of primary research results by combining open-source scientific material, namely a comparison of craniofacial features (Cfc) between Crouzon's syndrome (CS) patients and non-CS populations. All articles published up to October 7, 2021, were included in the search of PubMed, Google Scholar, Scopus, Medline, and Web of Science. The PRISMA guidelines were followed to conduct this study. PECO framework was applied in the following ways: Those who have CS are denoted by the letter P, those who have been diagnosed with CS via clinical or genetic means by the letter E, those who do not have CS by the letter C, and those who have a Cfc of CS by the letter O. Independent reviewers collected the data and ranked the publications based on their adherence to the Newcastle-Ottawa Quality Assessment Scale. A total of six case-control studies were reviewed for this meta-analysis. Due to the large variation in cephalometric measures, only those published in at least two previous studies were included. This analysis found that CS patients had a smaller skull and mandible volumes than those without CS.in terms of SNA° (MD = -2.33, p = <0.001, I2 = 83.6%) and ANB°(MD = -1.89, p = <0.005, I2 = 93.1%)), as well as ANS (MD = -1.87, p = 0.001, I2 = 96.5%)) and SN/PP (MD = -1.99, p = 0.036, I2 = 77.3%)). In comparison to the general population, people with CS tend to have shorter and flatter cranial bases, smaller orbital volumes, and cleft palates. They differ from the general population in having a shorter skull base and more V-shaped maxillary arches.

Synchondrosis fusion contributes to the progression of postnatal craniofacial dysmorphology in syndromic craniosynostosis.

Syndromic craniosynostosis (CS) patients exhibit early, bony fusion of calvarial sutures and cranial synchondroses, resulting in craniofacial dysmorphology. In this study, we chronologically evaluated skull morphology change after abnormal fusion of the sutures and synchondroses in mouse models of syndromic CS for further understanding of the disease. We found fusion of the inter-sphenoid synchondrosis (ISS) in Apert syndrome model mice (Fgfr2S252W/+ ) around 3 weeks old as seen in Crouzon syndrome model mice (Fgfr2cC342Y/+ ). We then examined ontogenic trajectories of CS mouse models after 3 weeks of age using geometric morphometrics analyses. Antero-ventral growth of the face was affected in Fgfr2S252W/+ and Fgfr2cC342Y/+ mice, while Saethre-Chotzen syndrome model mice (Twist1+/- ) did not show the ISS fusion and exhibited a similar growth pattern to that of control littermates. Further analysis revealed that the coronal suture synostosis in the CS mouse models induces only the brachycephalic phenotype as a shared morphological feature. Although previous studies suggest that the fusion of the facial sutures during neonatal period is associated with midface hypoplasia, the present study suggests that the progressive postnatal fusion of the cranial synchondrosis also contributes to craniofacial dysmorphology in mouse models of syndromic CS. These morphological trajectories increase our understanding of the progression of syndromic CS skull growth.

Identification of Diagnostic Variants in FGFR2 and NPR2 Genes in a Chinese Family Affected by Crouzon Syndrome and Acromesomelic Dysplasia, Type Maroteaux.

This study aims to conduct a comprehensive clinical and genetic investigation on a large family with members having various phenotypes, including acromesomelic dysplasia, type Maroteaux (AMDM), idiopathic short stature (ISS), Crouzon syndrome (CS). Prenatal diagnosis was performed on the high-risk fetus. We performed the whole-exome sequencing on three members with AMDM, ISS, or CS. Detailed genotypes and phenotypes were investigated on members of this 4-generation family. Genetic analysis identified three variants, which were designated as p.Val548del, p.Arg989Gln in natriuretic peptide receptor B/guanylate cyclase B (NPR2), and p.Cys342Tyr in fibroblast growth factor receptor-2 (FGFR2). Compound heterozygous variation consisting of p.Val548del and p.Arg989Gln caused AMDM. NPR2 heterozygous variant carriers exhibited normal height or ISS. The p.Cys342Tyr mutation of FGFR2 causes the typical clinical phenotype of CS. The fetus carried the heterozygous p.Val548del and p.Cys342Tyr mutations, with ultrasound results showing exophthalmos, parrot-beaked nose, low and flat frontal skull, and intrauterine growth retardation at the second and third trimesters of gestation. We are reporting those two novel mutations (p.Val548del and p.Arg989Gln) in NPR2 and a p.Cys342Tyr mutation in FGFR2 in an extended Chinese family. This finding extended the genotype-phenotype spectra of ISS, AMDM, and CS related to pathogenic variants.

Type II Pfieffer misdiagnosed as Crouzon syndrome with additional features of supernumerary teeth and localized symmetrical gigantism: a case report.

BACKGROUND: Pfieffer syndrome is among the syndromes seen in the recognized variant of the FGFR2 gene. There are several conditions related to this variant and a very closely related condition is Crouzon syndrome. This case is important to report because the neonate was a delayed referral from another region, without clear counseling and information on the gravity of situation. We describe additional features , not previously described in Pfieffer or Crouzon syndrome, supernumerary teeth and localized symmetrical gigantism of thumbs and great toes on both sides. That a genetic testing is essential to further manage and counsel to avoid lost opportunities for future births. Several cases are seen in this unit annually, and there is need for a more consolidated and comprehensive counseling and genetic testing. Once early diagnosis is done and the case is recognized to be untreatable, it was avert the need to refer. CASE PRESENTATION: A 2-week-old male African neonate referred from outside the region, presented with massive proptosis soon after delivery, with signs of pan-ophthalmitis and neonatal sepsis. The infant had additional multiple malformations and features initially diagnosed as Crouzon syndrome , but later confirmed after genetic testing to be Type II Pfieffer syndrome. A through clinical evaluation and genetic testing would prevent undue referral to a tertiary center, or if needed, the baby should have been referred much earlier. The uniqueness of this case is the presence of supernumerary teeth. CONCLUSION: A complicated, difficult to remedy case, referred to tertiary center, investigated, and sent back home with no significant intervention. Genetic test confirmed the typical findings of Pfieffer Type II. Presented for describing additional unique features of supernumerary teeth and localized gigantism and ethical challenges in management.

FGFR2 Mutation p.Cys342Arg Enhances Mitochondrial Metabolism-Mediated Osteogenesis via FGF/FGFR-AMPK-Erk1/2 Axis in Crouzon Syndrome.

BACKGROUND: Crouzon syndrome ([OMIM] #123500) caused by FGFR2 mutation is an autosomal dominant syndrome with craniosynostosis, the underlying mechanism of which remains obscure. METHODS: First, whole exome sequencing was used to screen the possible pathogenic variant in two sporadic patients with Crouzon syndrome. The investigation of primary and secondary structures as well as the conservation analysis of FGFR2 mutation (p.Cys342Arg) was performed. Then, wild-type and mutant overexpression plasmids were constructed and transfected into pre-osteoblastic murine cell line MC3T3-E1 cells. Osteogenesis and mitochondrial metabolism were analyzed by CCK8, ALP staining and ALP activity, alizarin red staining, qRT-PCR, Western blot, seahorse assays and mitochondrial staining. The siRNA targeting FGFR2 and domain negative FGFR2 were designed for verification. RESULTS: First, FGFR2 mutation (p.Cys342Arg) was detected in two sporadic Chinese Crouzon syndrome patients. FGFR2 p.Cys342Arg promoted the osteogenic differentiation of MC3T3-E1 cells through the upregulation of AMP-activated protein kinase (AMPK)-Erk1/2 signal pathway. Furthermore, FGFR2 p.Cys342Arg enhanced oxidative phosphorylation and converted mitochondrial fusion to the fission of MC3T3-E1, promoting osteogenic differentiation and craniosynostosis in Crouzon syndrome. Additionally, AMPK or Erk1/2 inhibitors delayed the cranial suture closure. CONCLUSION: FGFR2 mutation p.Cys342Arg promotes osteogenesis by enhancing mitochondrial metabolism-mediated via FGF/FGFR-AMPK-Erk1/2 axis, which indicates the potential of therapy targeting AMPK or Erk1/2 for syndromic craniosynostosis treatment.

Posterior Vault Distraction Outcomes in Patients With Severe Crouzon Syndrome Resulting from Ser347Cys and Ser354Cys Mutations.

BACKGROUND: In this study, the authors present the outcomes of 4 patients with a severe form of Crouzon syndrome characterized by mutation of fibroblast growth factor receptor 2 (FGFR2) c.1040 C > G p.Ser347Cys or the pathogenic c.1061C > G p.Ser354Cys variant of FGFR2, who underwent posterior vault distraction osteogenesis (PVDO) to alleviate elevated intracranial pressure. METHODS: Patients with diagnosed Crouzon syndrome who were found by genetic testing to have an FGFR2 c.1040 C > G p.Ser347Cys mutation or the c.1061C > G p.Ser354Cys variant were included. Outcome data and presence of hydrocephalus, Chiari Malformation type I (CMIs), and the presence/absence of a tracheostomy were recorded. RESULTS: Three patients with the FGFR2 c.1040 C > G p.Ser347Cys mutation and 1 with the pathogenic FGFR2 c.1061C > G p.Ser354Cys variant were identified as having characteristics of severe Crouzon syndrome. The mean age at PVDO was 15 months and the mean posterior advancement was 20 mm. All 4 patients experienced sufficient relief of the elevated intracranial pressure from the PVDO to prevent the need for shunt placement, stabilize the ventricular dimensions (n = 2), and resolve the CMIs (n = 2). Intracranial pressure screening ruled out malignant cerebrospinal fluid volume increase. CONCLUSIONS: PVDO effectively prevented hydrocephalus and resolved CMIs, successfully alleviating intracranial pressure and maximizing clinical outcomes for patients with severe Crouzon syndrome.

FGFR3 overactivation in the brain is responsible for memory impairments in Crouzon syndrome mouse model.

Crouzon syndrome with acanthosis nigricans (CAN, a rare type of craniosynostosis characterized by premature suture fusion and neurological impairments) has been linked to a gain-of-function mutation (p.Ala391Glu) in fibroblast growth factor receptor 3 (FGFR3). To characterize the CAN mutation's impact on the skull and on brain functions, we developed the first mouse model (Fgfr3A385E/+) of this syndrome. Surprisingly, Fgfr3A385E/+ mice did not exhibit craniosynostosis but did show severe memory impairments, a structurally abnormal hippocampus, low activity-dependent synaptic plasticity, and overactivation of MAPK/ERK and Akt signaling pathways in the hippocampus. Systemic or brain-specific pharmacological inhibition of FGFR3 overactivation by BGJ398 injections rescued the memory impairments observed in Fgfr3A385E/+ mice. The present study is the first to have demonstrated cognitive impairments associated with brain FGFR3 overactivation, independently of skull abnormalities. Our results provide a better understanding of FGFR3's functional role and the impact of its gain-of-function mutation on brain functions. The modulation of FGFR3 signaling might be of value for treating the neurological disorders associated with craniosynostosis.

Phenotypic variability of syndromic craniosynostosis caused by c.833G > T in FGFR2: Clinical and genetic evaluation of eight patients from a five-generation family.

OBJECTIVE: Craniosynostosis is the result of the early fusion of cranial sutures. Syndromic craniosynostosis includes but not limited by Crouzon syndrome and Pfeiffer syndrome. Considerable phenotypic overlap exists among these syndromes and mutations in FGFR2 may cause different syndromes. This study aims to investigate the explanation of the phenotypic variability via clinical and genetic evaluation for eight patients in a large pedigree. METHODS: For each patient, comprehensive physical examination, cranial plain CT scan with three-dimensional CT reconstruction (3D-CT), and eye examinations were conducted. Whole exome sequencing was applied for genetic diagnosis of the proband. Variants were analyzed and interpreted following the ACMG/AMP guidelines. Sanger sequencing was performed to reveal genotypes of all the family members. RESULTS: A pathogenic variant in the FGFR2 gene, c.833G > T (p.C278F), was identified and proved to be co-segregate with the disease. Some symptoms of head, hearing, vision, mouth, teeth expressed differently by affected individuals. Nonetheless, all the eight patients manifested core symptoms of Crouzon syndrome without abnormality in the limbs, which could exclude diagnosis of Pfeiffer syndrome. CONCLUSION: We have established clinical and genetic diagnosis of Crouzon syndrome for eight patients in a five-generation Chinese family. Variability of clinical features among these familial patients was slighter than that in previously reported sporadic cases.

A case of blepharophimosis: Freeman Sheldon syndrome.

PURPOSE: Important implications exist for ophthalmologists when considering possible early surgical intervention for potential amblyogenic anatomical abnormalities. The authors discuss the risks and benefits from an ophthalmological perspective of different interventions and review the genetic testing that confirmed the diagnosis. OBSERVATIONS: The authors describe the findings and management of an infant with Freeman Sheldon syndrome presenting with blepharophimosis of both eyelids resulting in inability to open both eyes during the first several days of life. Although the mode of inheritance for Freeman Sheldon syndrome (formerly known as Whistling Face Syndrome) is often autosomal dominant, our patient had no known family history of congenital abnormalities or consanguinity. However, genetic testing confirmed a heterozygous variant in MYH3, consistent with autosomal dominant Freeman Sheldon Syndrome. When our patient required gastrostomy (G-tube_placement, we performed an exam under anesthesia (EUA)). As is typical for Freeman Sheldon syndrome patients, intubation was difficult and complicated by pneumothorax. Eye-opening improved slightly after several weeks of life; however, the decision was made to proceed with eyelid surgery to prevent deprivation amblyopia. Surgery is scheduled for a future date. Additionally, the patient had congenital nasolacrimal duct obstruction of the left eye; however, a probing and irrigation failed because of obstruction from the abnormal facial anatomy. CONCLUSIONS AND IMPORTANCE: Patients with Freeman Sheldon syndrome are at increased risk for complications from anesthesia and surgery. Risks and benefits should be strongly considered and discussed with parent(s)/guardian(s) prior to any surgical intervention. Genetic testing of the MYH3 gene can confirm the diagnosis.

Surgical Result and Identification of FGFR2 Variants Using Whole-Exome Sequencing in a Chinese Family With Crouzon Syndrome.

ABSTRACT: Crouzon syndrome is considered as one of the most common craniosynostosis syndromes with a prevalence of 1 in 65,000 individuals, and has a close relationship with variants in fibroblast growth factor receptor 2. Here the authors described a Crouzon syndrome case, which was asked for surgery treatment for the symptom of multisuture craniosynostosis. Mild midfacial retrusion, larger head circumference, proptosis, pseudo-prognathism, and dental malposition could also be found obviously. Then fronto-orbital advancement and cranial cavity expansion were performed to the child. After whole-exome sequencing (WES) and Sanger sequencing, gene variants in the exons 2 and 3 of FGFR2 were detected. And protein tyrosine 105 replaced by cysteine in the extracellular region of FGFR2 was also detected. After operation, she presented a satisfactory anterior plagiocephaly and scaphocephaly correction, and the result was satisfied by surgeons and her parents. Variants detected using WES have further research prospect.

Dental phenotype in Crouzon syndrome: A controlled radiographic study in 22 patients.

OBJECTIVE: This retrospective radiographic controlled study investigates the dental phenotype in patients with Crouzon syndrome to determine if differences are observed as suggested by the FGFR2C342Y/+ Crouzon mouse models, and whether these models could be of interest to study the role of this mutation in tooth development. DESIGN: We assessed dental phenotype using dedicated linear measurements in 22 children with Crouzon syndrome and compared tooth morphology in both primary and permanent dentitions to an age-matched control group. Descriptive statistics were performed with "Sex" and "Age" as covariates for the permanent tooth models and "Sex" only for the primary tooth models, to take into account potential confounding factors. RESULTS: We showed that permanent but not primary tooth dimensions were globally reduced in Crouzon syndrome, without microdontia. In permanent dentition, crown height, mesiodistal and faciolingual cervical diameters were reduced by 6.3%, 5.7% and 5.5% respectively (p < 0.05). CONCLUSION: Our results underline the implication of Fibroblast Growth Factor Receptor 2 (FGFR2) in dental development of humans and contribute to support FGFR2C342Y/+ Crouzon mouse models as partial replicas of this condition, including in the oral region.

Clinical signs, interventions, and treatment course of three different treatment protocols in patients with Crouzon syndrome with acanthosis nigricans.

OBJECTIVE: Crouzon syndrome with acanthosis nigricans (CAN) is a rare and clinically complex subtype of Crouzon syndrome. At three craniofacial centers, this multicenter study was undertaken to assess clinical signs in relation to the required interventions and treatment course in patients with CAN. METHODS: A retrospective cohort study of CAN was performed to obtain information about the clinical treatment course of these patients. Three centers participated: Erasmus Medical Centre, Rotterdam, the Netherlands; John Radcliffe Hospital, Oxford, United Kingdom; and Hôpital Necker-Enfants Malades, Paris, France. RESULTS: Nineteen patients (5 males, 14 females) were included in the study. All children were operated on, with a mean of 2.2 surgeries per patient (range 1-6). Overall, the following procedures were performed: 23 vault expansions, 10 monobloc corrections, 6 midface surgeries, 11 foramen magnum decompressions, 29 CSF-diverting surgeries, 23 shunt-related interventions, and 6 endoscopic third ventriculostomies, 3 of which subsequently required a shunt. CONCLUSIONS: This study demonstrates that patients with the mutation c.1172C>A (p.Ala391Glu) in the FGFR3 gene have a severe disease trajectory, requiring multiple surgical procedures. The timing and order of interventions have changed among patients and centers. It was not possible to differentiate the effect of a more severe clinical presentation from the effect of treatment order on outcome.

Clinical assessment and FGFR2 mutation analysis in a Chinese family with Crouzon syndrome: A case report.

RATIONALE: Crouzon syndrome is an autosomal dominant genetic disorder caused by mutations in fibroblast growth factor receptor 2 (FGFR2) and one of the most common types of craniosynostosis. Here we report the detection of FGFR2 mutation and its related clinical findings in 2 patients with Crouzon syndrome from a Chinese family. PATIENT CONCERNS: We report a case of a 28-year-old male patient presented with the chief complaint of gradually blurring of his eyes over the last 6 months before visiting our clinics. History revealed low visual acuity in his right eye since childhood. Physical examination showed that both the patient and his mother have the appearance of craniofacial dysostosis, mandibular prognathism, ocular proptosis, short superior lip, scoliosis, and thoracic deformity. DIAGNOSIS: Auxiliary examinations lead to the diagnosis of Crouzon syndrome with binocular optic atrophy, myelinated retina nerve fibers, and ametropia in both eyes, and amblyopia in the right eye of the male patient. The molecular genetic analysis confirmed the diagnosis by detecting a heterozygous pathogenic mutation c.1026C > G (C342W) in exon 10 of FGFR2 in both the patient and his mother, but not in any of the unaffected family members. INTERVENTIONS AND OUTCOMES: None. LESSONS: Our study confirms the presence of optic nerve atrophy in patients with Crouzon syndrome carrying FGFR2 C342W mutations and indicates that MRI and funduscopy should be performed to examine the optic nerve changes for patients with Crouzon syndrome.

Nager syndrome in patient lacking acrofacial dysostosis: Expanding the phenotypic spectrum of SF3B4-related disease.

Nager syndrome epitomizes the acrofacial dysostoses, which are characterized by craniofacial and limb defects. The craniofacial defects include midfacial retrusion, downslanting palpebral fissures, prominent nasal bridge, and micrognathia. Limb malformations typically include hypoplasia or aplasia of radial elements including the thumb. Nager syndrome is caused by haploinsufficiency of SF3B4, encoding a spliceosomal protein called SAP49. Here, we report a patient with a loss of function variant in SF3B4 without acrofacial dysostosis or limb defects, whose reason for referral was developmental and growth delay. This patient is evidence of a broader phenotypic spectrum associated with SF3B4 variants than previously appreciated.

Characterization of dental pulp stem cells isolated from a patient diagnosed with Crouzon syndrome.

Stem cells isolated from patients with rare diseases are important to elucidate their pathogeny and mechanisms to enable regenerative therapy. However, the mechanisms underlying tissue regeneration using patient-derived dental pulp stem cells (DPSCs) are unclear. In this study, we investigated the levels of mRNA and protein expression related to cellular differentiation of Crouzon syndrome patient-derived DPSCs (CS-DPSCs) with a Gly338Arg fibroblast growth factor receptor 2 mutation. Multipotency-related gene expression levels were equivalent in both healthy donor DPSCs and CS-DPSCs. CS-DPSCs showed higher osteocalcin (OCN) expression than healthy donor DPSCs. CS-DPSCs showed a lower increase in the rate of OCN expression among phorbol 12-myristate 13-acetate (PMA)-treated cells than healthy donor DPSCs compared with untreated control cells. CS-DPSCs showed a lower phosphorylation rate of p38 and p44/42 in PMA-treated cells than healthy donor DPSCs compared with untreated control cells. These results demonstrate that CS-DPSCs have higher OCN expression and lower PMA stimulation-responsiveness than healthy donor DPSCs.

Severe craniolacunae and upper and lower extremity anomalies resulting from Crouzon syndrome, FGFR2 mutation, and Ser347Cys variant.

Crouzon syndrome is a rare form of syndromic craniosynostosis (SC) characterized by premature fusion of the cranial and facial sutures, elevated intracranial pressure, varying degrees of ocular exposure due to exorbitism, and airway compromise caused by midface retrusion. Craniolacunae and upper and lower extremity anomalies are not frequently found in Crouzon syndrome. We present a girl with Crouzon syndrome caused by c.1040 C > G, p.Ser347Cys, a pathogenic mutation in the FGFR2 gene with atypical characteristics, including craniolacunae resembling severe Swiss cheese type of bone formation, and upper and lower extremity anomalies which are more commonly associated with Pfeiffer syndrome patients. Distinguishing between severe Crouzon syndrome patients and patients who have mild and/or moderate Pfeiffer syndrome can be challenging even for an experienced craniofacial surgeon. An accurate genotype diagnosis is essential to distinguishing between these syndromes, as it provides predictors for neurosurgical complications and facilitates appropriate family counseling related to long-term outcomes.