Central nervous system and cervical spine abnormalities in Apert syndrome

Apert syndrome: neurosurgical outcomes and complications following posterior vault distraction osteogenesis

PURPOSE

Posterior vault distraction osteogenesis (PVDO) has been utilized during the past 15 years to treat a variety of clinical features commonly presented by patients with Apert syndrome. The objective of this study is to determine the efficacy of PVDO in addressing both elevated intracranial pressure (ICP) and ectopia of the cerebellar tonsils (ECT) in young Apert patients. In addition, we aimed to determine the prevalence of hydrocephalus in Apert syndrome patients who underwent PVDO.

METHODS

A retrospective study was made with a cohort of 40 consecutive patients with syndromic craniosynostosis (SC), previously diagnosed with Apert syndrome, who underwent PVDO between 2012 and 2022, and thereafter received at least 1 year of follow-up care. Demographic data and diagnosis, along with surgical and outcome data, were verified using medical records, clinical photographs, radiologic examination, and interviews with the parents of all cohort patients.

RESULTS

The average patient age when PVDO was performed was 12.91 ± 10 months. The average posterior advancement distance achieved per patient was 22.68 ± 5.26 mm. The average hospital stay per patient was 3.56 ± 2.44 days. The average absolute and relative blood transfusion volumes were 98.47 ml and 17.63 ml/kg, respectively. Although five patients (14%) presented ECT preoperatively, this condition was completely resolved by PVDO in three of these five patients. One of the three patients whose ECT had completely resolved presented syringomyelia postoperatively, requiring subsequent extra dural foramen magnum decompression. All of the remaining four patients were asymptomatic for ECT for at least 1 year of follow-up, and none of these four patients required any additional treatments to address ECT. Two patients presented hydrocephalus requiring ventriculoperitoneal shunt placement.

CONCLUSIONS

This study demonstrates that PVDO both reduces diagnosed elevated ICP symptoms and is partially effective in treating ECT in Apert syndrome patients. Hydrocephalus in Apert syndrome is an uncommon feature. The effectiveness of PVDO in addressing hydrocephalus is uncertain.

Early Cranioplasty in an Apert's Syndrome Infant With Occipital Encephalocele

Apert's syndrome (AS) is a rare congenital malformation characterized by distinctive clinical manifestations such as syndactyly of the extremities and midface retrusion, which set it apart from other syndromes. This condition often presents with craniosynostosis and, less commonly, central nervous system abnormalities like encephalocele. In this report, we present a typical case of Apert syndrome with an occipital encephalocele. The infant had plagio-brachycephaly due to craniosynostosis and required urgent repair of the occipital encephalocele. At 1 month of age, we performed both the encephalocele repair and early cranioplasty for autologous bone grafting. This case underscores the importance of early diagnosis and surgical interventions in Apert's syndrome cases with encephalocele.

Preprocedural Electrophysiological Monitoring in Craniofacial Surgery for a Patient with Chiari Malformation

Head and neck positioning is a key element of craniofacial reconstructive surgery and can become challenging when intervention necessitates broad exposure of the calvarium. We present a case of craniosynostosis secondary to Apert's syndrome requiring anterior and posterior cranial vault access during surgical correction. A modified sphinx position was used that required significant neck extension. The patient had concurrent Chiari I malformation with brain stem compression so intraoperative neuromonitoring (IONM) was used to ensure that there were no negative effects on the neural elements with positioning. This highlights benefits of IONM in a setting not typically associated with its use.

Apert Syndrome with Agenesis of the Corpus Collosum - Case Report

Apert syndrome (Acrocephalosyndactylia type 1) belongs to the group of extremely rare congenital dysmorphic syndromes. It is characterized by craniostenosis with very early fusion of the skull and / or cranial base sutures, facial hypoplasia, symmetrical syndactyly of the fingers and toes and other systemic malformations. Multiple CNS abnormalities are common, but simultaneous occurrence of Apert syndrome and agenesis of corpus callosum is estimated about 10%.

We present a male patient born after first, normal and controlled pregnancy and term, naturally birth, in which the Apert syndrome was diagnosed, based on the clinical presentation of the skull and face and syndactyly of fingers and toes. Neurological examination established generalized hypotonia and aggravated provocation of the primitive reflexes. Neurosonography showed complete agenesis of the corpus callosum, which makes this case a rare form of this syndrome. The head X-rays showed turricephalic skull shape and suture’s synostoses, which is demonstrated in more detail at computed tomography finding. The hands and feet X-rays showed bone synostosis of fingers and toes. The video-electroencephalogram recorded intermittent depression of electrocortical activity. There was conducted the multidisciplinary examination in order to examine the possibility of reconstructive and plastic surgical correction of the anomalies.

The neurodevelopmental disorders in patients with Apert syndrome can be manifested by a variety of congenital malformations, but considering its rare occurrence, the significance of these abnormalities remains unknown.

Craniofacial morphology in Apert syndrome: a systematic review and meta-analysis

This meta-analysis aims to compare Apert syndrome (AS) patients with non-AS populations (not clinically or genetically diagnosed) on craniofacial cephalometric characteristics (CCC) to combine publicly available scientific information while also improving the validity of primary study findings. A comprehensive search was performed in the following databases: PubMed, Google Scholar, Scopus, Medline, and Web of Science, an article published between 1st January 2000 to October 17th, 2021. PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed to carry out this systematic review. We used the PECO system to classify people with AS based on whether or not they had distinctive CCC compared to the non-AS population. Following are some examples of how PECO has been used: People with AS are labeled P; clinical or genetic diagnosis of AS is labeled E; individuals without AS are labeled C; CCC of AS are labeled O. Using the Newcastle-Ottawa Quality-Assessment-Scale, independent reviewers assessed the articles' methodological quality and extracted data. 13 studies were included in the systematic review. 8 out of 13 studies were score 7-8 in NOS scale, which indicated that most of the studies were medium to high qualities. Six case-control studies were analyzed for meta-analysis. Due to the wide range of variability in CCC, we were only able to include data from at least three previous studies. There was a statistically significant difference in N-S-PP (I2: 76.56%; P = 0.014; CI 1.27 to - 0.28) and Greater wing angle (I2: 79.07%; P = 0.008; CI 3.07-1.17) between AS and control subjects. Cleft palate, anterior open bite, crowding in the upper jaw, and hypodontia occurred more frequently among AS patients. Significant shortening of the mandibular width, height and length is the most reported feature in AS patients. CT scans can help patients with AS decide whether to pursue orthodontic treatment alone or to have their mouth surgically expanded. The role of well-informed orthodontic and maxillofacial practitioners is critical in preventing and rehabilitating oral health issues.

Differential diagnosis of syndromic craniosynostosis: a case series

Purpose

Syndromic craniosynostosis is a rare genetic disease caused by premature fusion of one or multiple cranial sutures combined with malformations of other organs. The aim of this publication is to investigate sonographic signs of different syndromic craniosynostoses and associated malformations to facilitate a precise and early diagnosis.

Methods

We identified in the period of 2000–2019 thirteen cases with a prenatal suspected diagnosis of syndromic craniosynostosis at our department. We analyzed the ultrasound findings, MRI scans, genetic results as well as the mode of delivery, and postnatal procedures.

Results

Eight children were diagnosed with Apert Syndrome, two with Saethre Chotzen syndrome, one with Crouzon syndrome, and one with Greig cephalopolysyndactyly syndrome. One child had a mutation p.(Pro253Leu) in the FGFR2 gene. We identified characteristic changes of the head shape as well as typical associated malformations.

Conclusion

Second trimester diagnosis of syndromic craniosynostosis is feasible based on the identified sonographic signs. In case of a suspected diagnosis a genetic, neonatal as well as surgical counseling is recommended. We also recommend to offer a fetal MRI. The delivery should be planned in a perinatal center.

Apert syndrome: Cranial procedures and brain malformations in a series of patients

Background:

Apert syndrome is one of the most severe craniofacial disorders. This study aims to describe the craniofacial surgeries and central nervous system malformations of a cohort of children with Apert syndrome treated in the past 20 years and to compare these data with previously published data.

Methods:

Retrospective analysis of a series of patients with Apert syndrome treated between 1999 and 2019 in our hospital. Information was analyzed regarding craniofacial procedures, hydrocephalus and presence of shunts, Chiari malformation Type 1, and other brain malformations such as corpus callosum and septum pellucidum anomalies.

Results:

Thirty-seven patients were studied. Ventriculoperitoneal shunt prevalence was 24.3%, and 8.1% of patients required decompressive surgery for Chiari malformation. All of them needed at least one cranial vault remodeling procedure. The median age for this procedure was 8 months. In 69.7% of patients, the first cranial vault intervention was performed in the fronto-orbital region. In 36.4% of patients, a midface advancement had been performed at the time of this review, although this proportion was very dependent on the follow-up period and the age of the patients. The median age for the midface advancement procedure was 5.25 years. Anomalies of the corpus callosum and the septum pellucidum were reported in 43.2% and 59.5% of patients, respectively.

Conclusion:

Apert syndrome is a type of syndromic craniosynostosis, and patients usually require one or more cranial and facial surgeries. In comparison with other syndromic craniosynostosis types, Apert syndrome less frequently requires a VP shunt or treatment for a Chiari malformation.

Cranial Fossa Volume and Morphology Development in Apert Syndrome

BACKGROUND

Apert syndrome causes normal or enlarged intracranial volume overall as patients grow. This study aimed to trace the segmental anterior, middle, and posterior cranial fossae volume and structural morphology in these patients, to help discern a more focused and individualized surgical treatment plan for patients with Apert syndrome.

METHODS

This study included 82 preoperative computed tomographic scans (Apert, n = 32; control, n = 50) divided into five age-related subgroups. The scans were measured using image processing and three-dimensional modeling software.

RESULTS

The middle cranial fossa volume was increased and was the earliest change noted. It was increased by 45 percent (p = 0.023) compared with controls before 6 months of age and remained increased into adulthood (161 percent, p = 0.016), with gradually increasing severity. The anterior and posterior cranial fossae volumes also increased, by 35 percent (p = 0.032) and 39 percent (p = 0.007), respectively. Increased depth of cranial fossae contributed most to the increase in volumes of patients with Apert syndrome, with correlation coefficients of 0.799, 0.908, and 0.888 for anterior, middle, and posterior cranial fossa, respectively. The intracranial volume was increased 12 percent (p = 0.098) across the entire test age range (0 to 26 years old), but only had statistical significance during the age range of 6 to 18 years (22 percent, p = 0.001).

CONCLUSIONS

Malformation of the middle cranial fossa is an early, perhaps the initial, pivotal cranial morphologic change in Apert syndrome. Increased cranial fossae depth is an inherent characteristic of the maldevelopment. Normalization of cranial volume and circumference overall may not achieve a normal skull structure, as it does not correct regional craniocerebral disproportion.

Apert syndrome: magnetic resonance imaging (MRI) of associated intracranial anomalies

INTRODUCTION

Apert syndrome is one of the most common craniosynostosis syndrome caused by mutations in genes encoding fibroblast growth factor receptor 2 (FGFR2). It is characterized by multisuture craniosynostosis, midfacial hypoplasia, abnormal skull base development and syndactyly of all extremities. Apert syndrome is associated with a wide array of central nervous system (CNS) anomalies, possibly the cause of the common occurrence of mental deficiency in patients with Apert syndrome. These CNS anomalies can be broadly classified into two groups; (1) those that are primary malformations and (2) those that occur secondary to osseous deformity/malformation.

CONCLUSION

Familiarity with CNS anomalies associated with Apert syndrome is important to both clinicians and radiologist as it impacts on management and prognostication. Cognitive development of patients has been linked to associated CNS anomalies, timing of surgery and social aspects. These associated anomalies can be broadly classified into (1) those that are primary malformations and (2) those that occur secondary to osseous deformity/malformation, as illustrated in our review paper.

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.

Apert syndrome: A consensus on the management of Apert hands

INTRODUCTION

Apert Syndrome is a congenital condition characterised by primary craniosynostosis, midfacial malformations and complex symmetrical malformations of the hands and feet. The hands demonstrate one of the most complex collections of congenital upper limb deformities, posing a significant challenge for the paediatric hand surgeon. This study examines the extant literature and current practice of the four UK specialist craniofacial units regarding the management of Apert hands in order to provide a basis for guideline development.

METHODS

The current literature was reviewed. Survey-type questionnaires were distributed to the four UK specialist craniofacial units and responses analysed.

RESULTS

Management of the Apert hand is largely dictated by the degree of malformation present. Although all units aim to achieve a five digit hand, variation in the timing of surgery, operative protocols and mobilisation policies exist.

CONCLUSION

The results of this study provide an interesting snapshot of the current management of Apert hands across four UK craniofacial surgery units. The four UK units remain congruent on most areas surrounding the management of Apert hands although some minor inter-unit variation exists. A multidisciplinary approach to management remains fundamental in optimising the regain of function and aesthetically acceptable hands.

Apert syndrome: Surgical outcomes and perspectives

PURPOSE

Apert syndrome is a rare congenital malformation with severe craniofacial anomalies. The aim of this study was to review the outcomes of craniofacial and neurosurgical interventions in Apert syndrome patients treated at a single institution.

MATERIALS AND METHODS

A retrospective review of all patient records with a diagnosis of Apert syndrome assessed and managed in the Australian Craniofacial Unit (ACFU) from 1985 to 2013 was conducted.

RESULTS

A total of 94 patients were identified, and 130 transcranial procedures were performed. Of the patients, 83 underwent a fronto-orbital advancement (FOA) as their primary procedure, and 18 patients also underwent a posterior vault procedure. Twenty patients underwent a fronto-facial monobloc advancement. Overall, 70% of patients underwent at least 2 transcranial procedures. Shunts were inserted in 2 patients preoperatively and in 5 patients postoperatively for cerebrospinal fluid (CSF) leaks or acute hydrocephalus. Re-do FOAs were performed in 8 patients. Patients who underwent an FOA at the age of more than 18 months had no recurrence of raised intracranial pressure (ICP). Of 18 patients who also underwent a posterior vault procedure, 1 patient had recurrence of raised ICP. Midfacial surgery was performed early if there was evidence of obstructive sleep apnoea (OSA), but delayed midfacial surgery was preferred. Complications were reported in 18% of procedures. The most common complications were CSF leaks and acute hydrocephalus.

CONCLUSION

Shunting is rarely required in Apert syndrome patients, confirming a predominantly nonprogressive ventriculomegaly. FOA appears to be a more stable procedure when performed at an age of more than 18 months. Undergoing a posterior vault procedure may reduce the risk of recurrent raised ICP and lead to fewer transcranial procedures needed in childhood. Midfacial surgery should be delayed until adolescence where there is no evidence of OSA, psychological disturbance, or complications of exorbitism. Complications are rare when these patients are treated by an experienced craniofacial team.