Isolated frontosphenoidal craniosynostosis (IFSC) is rare, historically misdiagnosed as coronal synostosis due to phenotypic overlap. Traditionally viewed as sporadic, its genetic basis was largely unexplored. Recent identification of pathogenic FGFR3 variants in IFSC patients challenges this view, suggesting a genetic etiology and necessitating molecular evaluation. This study aims to establish a genetic association between premature cranial suture closure and variants of the FGFR3 gene. This case report presents a rare instance of IFSC in a 10-month-old female infant, characterized by severe plagiocephaly due to premature fusion of the frontosphenoidal suture. Through high-resolution three-dimensional computed tomography imaging, the diagnosis was confirmed, and genetic testing revealed a heterozygous pathogenic FGFR3 missense variant (c.749C>G; p.Pro250Arg), previously associated with Muenke syndrome. This finding establishes a novel genetic association for IFSC, challenging the traditional view of its sporadic nature. The patient underwent successful unilateral fronto-orbital advancement and remodeling (FOAR), resulting in significant improvement in cranial symmetry. This case highlights the importance of molecular genetic testing in nonsyndromic craniosynostosis and the potential role of FGFR3 variants in IFSC. Early diagnosis and surgical intervention are crucial, advocating for a staged genetic testing approach in similar cases. These findings emphasize IFSC's genetic basis and its consideration in cranial deformity diagnoses.

In craniosynostosis distinctive craniofacial and oral growth patterns are to be expected. This study aims to determine maxillary anomalies in craniosynostosis patients with Muenke syndrome, Saethre-Chotzen syndrome or TCF12-related craniosynostosis, using a three-dimensional semi-automated setup measurement of digital dental casts. Symmetry analysis of the maxilla of craniosynostosis patients was performed with creation of a reference frame, a palatal mesh and a distance map. The outline of the palate was determined by landmarks with the use of a semi-automated technique and software algorithm and compared to healthy controls. All transverse dimensions were smaller in the craniosynostosis group compared to the. control group (p < 0.001; canine premolar right TCF12 p = 0.005). In Muenke syndrome, the palate was higher compared to the control group (left and right; p < 0.001). In Saethre-Chotzen syndrome, the palate was shallower (left p < 0.001; right p = 0.003) and the left palatal surface was smaller compared to the control group (p < 0.001). This retrospective case-control study indicates that Muenke syndrome, Saethre-Chotzen syndrome and TCF12-related craniosynostosis have distinctive maxillary characteristics compared to healthy controls. Muenke syndrome had a higher arched palate. and Saethre-Chotzen had a shallower palate compared to healthy controls. The intersurface distance (ISD) in both syndromes indicated a palatal anomaly.

Posterior cranial vault distraction osteogenesis (PVDO) is a commonly used cranial expansion procedure in infants and children with syndromic craniosynostosis. To date, there have been no reports of cranial nerve (CN) palsies in patients undergoing univector PVDO. In this article, the authors describe the case of a 27-month-old female with Muenke syndrome who underwent long-distance (> 30 mm) PVDO and developed bilateral abducens nerve (CN VI) palsy after 40 mm of distraction. Following partial reversal of the distraction during the activation phase, the authors observed complete resolution of this palsy. This report demonstrates that CN palsies are a potential complication for which the patient should be monitored, even when undergoing univector PVDO. Most notably, this report illustrates that a gradual reduction in the distraction distance can result in complete resolution of a CN VI palsy while also maintaining a significant degree of intracranial expansion. https://thejns.org/doi/10.3171/CASE24762.

Muenke syndrome is an autosomal dominant genetic disorder that is typically characterized by unilateral or bilateral coronal synostosis, macrocephaly, midface hypoplasia, and developmental delays. This article reports a case of Muenke syndrome with a soft cleft palate. A heterozygous missense mutation c.749C>G (p.P250A) was identified in the FGFR3 gene through genetic testing. The patient exhibited typical features including coronal synostosis, bilateral hearing loss, right accessory auricle, and developmental delays and underwent surgery to repair the soft cleft palate. Cases of Muenke syndrome with cleft palate in the literature are relatively rare, and common associated symptoms include coronal suture craniosynostosis and hearing impairment. This article reports a differential diagnosis with other craniosynostosis syndromes and provides a reference for clinical diagnosis and treatment. Muenke综合征是一种常染色体显性遗传病，通常表现为单侧或双侧冠状缝早闭、大头畸形、面中部发育不全和发育迟缓。本文报道了一例伴有软腭裂的Muenke综合征患者，通过基因检测发现患者存在FGFR3基因c.749C>G（p.P250A）杂合错义突变。患者表现出冠状缝早闭、双耳听力障碍、右侧副耳和发育迟缓，接受了软腭裂修复手术。通过汇总和比较文献中伴有腭裂的Muenke综合征病例，发现该类型病例较为罕见，常见伴发症状为冠状缝早闭和听力障碍。本文还进行了与其他颅缝早闭综合征的鉴别诊断，以期为临床诊疗提供参考。.