An Epidemiological Study of Nonsyndromal Craniosynostoses

The preoperative incidence of raised intracranial pressure in nonsyndromic sagittal craniosynostosis is underestimated in the literature

OBJECT

The presence of raised intracranial pressure (ICP) in untreated nonsyndromic, isolated sagittal craniosynostosis (SC) is an important functional indication for surgery.

METHODS

A retrospective review was performed of all 284 patients presenting with SC to the Oxford Craniofacial Unit between 1995 and 2010.

RESULTS

Intraparenchymal ICP monitoring was performed in 39 children following a standard unit protocol. Monitoring of ICP was offered for all patients in whom nonoperative management was considered on the basis of minimal deformity or in cases in which parents were reluctant to agree to corrective surgery. These patients presented at an older age than the rest of the cohort (mean age 56 months), with marked scaphocephaly (16/39, 41%), mild scaphocephaly (11, 28%), or no scaphocephalic deformity (12, 31%). Raised ICP was found in 17 (44%) patients, with no significant difference in its incidence among the 3 different deformity types. Raised ICP was not predicted by the presence of symptoms of ICP or developmental delay or by ophthalmological or radiological findings.

CONCLUSIONS

The incidence of raised ICP in SC reported here is greater than that previously published in the literature. The lack of a reliable noninvasive method to identify individuals with elevated ICP in SC mandates consideration of intraparenchymal ICP monitoring in all patients for whom nonoperative management is contemplated.

The path of the superior sagittal sinus in unicoronal synostosis

PURPOSE

This study investigates the anatomic relationship between the superior sagittal sinus (SSS) and the sagittal suture in infants with uncorrected unicoronal synostosis. The morphology of the SSS is also evaluated postoperatively to assess whether normalization of intracranial structures occurs following reconstruction.

METHODS

The study sample consisted of 20 computed tomography scans (10 preoperative, 6 postoperative, and 4 unaffected controls) obtained between 2001 and 2013. The SSS and the sagittal suture were outlined using Analyze imaging software. These data were used to measure the maximum lateral discrepancy between the SSS and the sagittal suture preoperatively and to assess for postoperative changes in the morphology of the SSS.

RESULTS

In children with uncorrected unicoronal synostosis, the SSS deviates to the side of the patent coronal suture posteriorly and tends to follow the path of the sagittal and metopic sutures. The lateral discrepancy between the SSS and the sagittal suture ranged from 5.0 to 11.8 mm, with a 99.9 % upper prediction bound of 14.4 mm. Postoperatively, the curvature of the SSS was statistically decreased following surgical intervention, though it remained significantly greater than in unaffected controls.

CONCLUSIONS

The SSS follows a predictable course relative to surface landmarks in children with unicoronal synostosis. When creating burr holes for craniotomies, the SSS can be avoided in 99.9 % of cases by remaining at least 14.4 mm from the lateral edge of the sagittal suture. Postoperative changes in the path of the SSS provide indirect evidence for normalization of regional brain morphology following fronto-orbital advancement.

Closing the Gap: Genetic and Genomic Continuum from Syndromic to Nonsyndromic Craniosynostoses

Craniosynostosis, a condition that includes the premature fusion of one or multiple cranial sutures, is a relatively common birth defect in humans and the second most common craniofacial anomaly after orofacial clefts. There is a significant clinical variation among different sutural synostoses as well as significant variation within any given single-suture synostosis. Craniosynostosis can be isolated (i.e., nonsyndromic) or occurs as part of a genetic syndrome (e.g., Crouzon, Pfeiffer, Apert, Muenke, and Saethre-Chotzen syndromes). Approximately 85 % of all cases of craniosynostosis are nonsyndromic. Several recent genomic discoveries are elucidating the genetic basis for nonsyndromic cases and implicate the newly identified genes in signaling pathways previously found in syndromic craniosynostosis. Published epidemiologic and phenotypic studies clearly demonstrate that nonsyndromic craniosynostosis is a complex and heterogeneous condition supporting a strong genetic component accompanied by environmental factors that contribute to the pathogenetic network of this birth defect. Large population, rather than single-clinic or hospital-based studies is required with phenotypically homogeneous subsets of patients to further understand the complex genetic, maternal, environmental, and stochastic factors contributing to nonsyndromic craniosynostosis. Learning about these variables is a key in formulating the basis of multidisciplinary and lifelong care for patients with these conditions.

Neurodevelopmental and esthetic results in children after surgical correction of metopic suture synostosis: a single institutional experience

INTRODUCTION

Metopic suture synostosis leading to trigonocephaly is considered the second most frequent type of craniosynostosis. Besides esthetic results, we present 25 consecutive pediatric cases operated upon metopic suture synostosis with a focus on the child's motor, speech, and neurocognitive development.

METHODS

Twenty-five children (aged 6 to 33 months; median 9.2 months) with trigonocephaly were operated upon between 2002 and 2012 with fronto-orbital advancement including frontal bone cranioplasty and fronto-orbital bandeau remodeling. Neurodevelopmental deficits were evaluated by a standardized questionnaire including gross motor function, manual coordination, speech, and cognitive function performed by independent pediatric/developmental neurologists before surgery and at 6 and 12 months of time interval postoperatively.

RESULTS

Twenty-one (84 %) boys and four (16 %) girls were included in this study. Mean follow-up period was 33 ± 28 months. Outcome analysis for esthetic results showed a high degree of satisfaction by the parents and treating physicians in 23 cases (92 %). Preoperative evaluation revealed neurodevelopmental deficits in 10 children (40 %; six mild, four moderate degree). Twelve children (48 %) were proven to have a normal preoperative neuropediatric development. Mild or moderate developmental restraints were no longer apparent in 6/13, improved but still apparent in 3/13, and stable in 4/13, 6 months after cranial vault reconstruction. At 12 months of follow-up, deficits were no longer present in 9/13 and improved in 4/13. Apart from this cohort, two children were diagnosed with a syndromic form, and one child had a fetal valproate syndrome. In these three children, neurodevelopmental deficits were more pronounced. Neurocognitive progress was obvious, but was comparably slower, and major deficits were still apparent at last follow-up. All children with proven mild/moderate/severe deficits received intensive physiotherapy, logopedic, or neurobehavioral support.

CONCLUSIONS

As shown in a single-center observation, surgical correction of metopic suture synostosis not only refines esthetic appearance but also might improve neurodevelopmental outcome if deficits are apparent, even in syndromic forms of the deformity under additional physiotherapy, logopedic, or neurobehavioral support.

Altered brain connectivity in sagittal craniosynostosis

OBJECT

Sagittal nonsyndromic craniosynostosis (sNSC) is the most common form of NSC. The condition is associated with a high prevalence (> 50%) of deficits in executive function. The authors employed diffusion tensor imaging (DTI) and functional MRI to evaluate whether hypothesized structural and functional connectivity differences underlie the observed neurocognitive morbidity of sNSC.

METHODS

Using a 3-T Siemens Trio MRI system, the authors collected DTI and resting-state functional connectivity MRI data in 8 adolescent patients (mean age 12.3 years) with sNSC that had been previously corrected via total vault cranioplasty and 8 control children (mean age 12.3 years) without craniosynostosis. Data were analyzed using the FMRIB Software Library and BioImageSuite.

RESULTS

Analyses of the DTI data revealed white matter alterations approaching statistical significance in all supratentorial lobes. Statistically significant group differences (sNSC < control group) in mean diffusivity were localized to the right supramarginal gyrus. Analysis of the resting-state seed in relation to whole-brain data revealed significant increases in negative connectivity (anticorrelations) of Brodmann area 8 to the prefrontal cortex (Montreal Neurological Institute [MNI] center of mass coordinates [x, y, z]: -6, 53, 6) and anterior cingulate cortex (MNI coordinates 6, 43, 14) in the sNSC group relative to controls. Furthermore, in the sNSC patients versus controls, the Brodmann area 7, 39, and 40 seed had decreased connectivity to left angular gyrus (MNI coordinates -31, -61, 34), posterior cingulate cortex (MNI coordinates 13, -52, 18), precuneus (MNI coordinates 10, -55, 54), left and right parahippocampus (MNI coordinates -13, -52, 2 and MNI coordinates 11, -50, 2, respectively), lingual (MNI coordinates -11, -86, -10), and fusiform gyri (MNI coordinates -30, -79, -18). Intrinsic connectivity analysis also revealed altered connectivity between central nodes in the default mode network in sNSC relative to controls; the left and right posterior cingulate cortices (MNI coordinates -5, -35, 34 and MNI coordinates 6, -42, 39, respectively) were negatively correlated to right hemisphere precuneus (MNI coordinates 6, -71, 46), while the left ventromedial prefrontal cortex (MNI coordinates 6, 34, -8) was negatively correlated to right middle frontal gyrus (MNI coordinates 40, 4, 33). All group comparisons (sNSC vs controls) were conducted at a whole brain-corrected threshold of p < 0.05.

CONCLUSIONS

This study demonstrates altered neocortical structural and functional connectivity in sNSC that may, in part or substantially, underlie the neuropsychological deficits commonly reported in this population. Future studies combining analysis of multimodal MRI and clinical characterization data in larger samples of participants are warranted.

A novel quantitative method for evaluating surgical outcomes in craniosynostosis: pilot analysis for metopic synostosis

Objective assessment of head shape has been an elusive goal in the management of craniosynostosis patients. Clinical judgment, craniometric indices, and computed tomography scans are the primary means through which a surgeon assesses this patient population. The purpose of this study was to examine and discuss the utility of the STARscanner for evaluation of surgical outcomes in metopic synostosis patients. A retrospective chart review of patients with metopic synostosis who underwent fronto-orbital advancement with pre- and postoperative STARscanner imaging at Texas Children's Hospital was performed. Two patients were identified and evaluation and discussion of the data produced by the STARscanner was undertaken. A novel symmetry index created by the authors, called the anterior-posterior volume ratio (APVR), was discussed for use in metopic synostosis patients. The postoperative growth metrics demonstrated an interval increase compared with the preoperative data. The anterior symmetry ratio, posterior symmetry ratio, overall symmetry ratio, cranial vault volumes, cranial vault asymmetry index, and cephalic ratio were not found to be useful in evaluating resolution of dysmorphology after fronto-orbital advancement in metopic synostosis. The APVR does not characterize dysmorphology, but may help show degree of expansion of the anterior cranial vault after fronto-orbital advancement. The STARscanner imaging device does not appear to have significant utility in characterizing head shape for surgical outcomes assessment in metopic synostosis. The minor utility of this device may be that it is a safe and fast way to derive growth parameters for both short-term and long-term follow-up of cranial vault remodeling.

Familial incidence and associated symptoms in a population of individuals with nonsyndromic craniosynostosis

PURPOSE

Craniosynostosis is a common cranial malformation occurring in 1 per 2,000-2,500 births. Isolated defects (nonsyndromic) occur in ~75% of cases and are thought to have multifactorial etiology. It is believed that each suture synostosis is a distinct disease, with varying phenotypes and recurrence rates.

METHODS

We analyzed family histories of 660 mutation-negative nonsyndromic craniosynostosis patients and symptoms in 189 of these patients.

RESULTS

The incidence rate of craniosynostosis was highest for first-degree relatives of probands with metopic craniosynostosis (6.4%), followed by those with complex craniosynostosis (4.9%), sagittal craniosynostosis (3.8%), lambdoid craniosynostosis (3.9%), and coronal craniosynostosis (0.7%). Across all suture types, siblings had a greater craniosynostosis incidence rate than parents (7.5 vs. 2.3%). In phenotype comparisons, patients with complex craniosynostosis had the highest frequency of reported symptoms and those with sagittal craniosynostosis had the lowest. Ear infections, palate abnormalities, and hearing problems were more common in complex craniosynostosis patients. Visual problems were more common in coronal craniosynostosis, and metopic craniosynostosis patients noted increased frequency of chronic cough.

CONCLUSION

Our data suggest that the genetic component of nonsyndromic craniosynostosis appears to be suture specific. The incidence rate of craniosynostosis among first-degree relatives varies by suture and family member. Additionally, the phenotype of each suture synostosis shows both unique and shared features.

A National Study on Craniosynostosis Surgical Repair

Objective

Our study aimed to use national data to assess the perioperative outcomes of craniosynostosis surgical repair.

Design

Data were obtained from the Agency for Healthcare Research and Quality Healthcare Cost and Utilization Project Kids Inpatient Database from 1997, 2000, 2003, and 2006.

Setting

Community hospitals in the United States.

Patients

The cohort was identified using the ICD-9-CM procedure codes for craniosynostosis surgical repair (2.01, 2.03, 2.04, 2.06).

Main Outcome Measures(s)

We determined patient and hospital characteristics. We clustered patients by age group (7 months, 7 to 12 months, 1 to 3 years) and assessed mortality, comorbidities, mean length of stay (LOS), and total charge. We performed logistic regression with our dependent variable being longer average hospital stay: LOS > 4.2 days.

Results

We found 3426 patients. Average age at the time of surgery was 181 days (SD 84). Average length of stay was 4.2 days. The majority of the patients were boys (66%), white (71%), and insured (93%). Nearly all patients underwent surgery in a teaching hospital (98%) in urban centers (99%). Approximately 10% of patients experienced an acute complication, most commonly hemorrhages or hematomas and airway or respiratory failure. Patients ages 1 to 3 years had the highest rates of comorbidities and a longer LOS. Mortality rate was <1%.

Conclusions

Craniosynostosis surgery is safe with low rates of mortality and acute complications. LOS >4.2 appears to be associated more with comorbidities than with complications. Higher rates of comorbidities and LOS >4.2 days for patients age 1 to 3 years warrant addition research to assess potential barriers to care.

Second family with the Boston-type craniosynostosis syndrome: novel mutation and expansion of the clinical spectrum

Craniosynostosis, caused by early fusion of one or more cranial sutures, can affect the coronal or lambdoid sutures, or include premature fusion of the sagittal (scaphocephaly) or metopic suture (trigonocephaly). Often occurring as isolated finding, their co-existence in a craniosynostosis syndrome is infrequent. We describe a four-generation family with variable expression of a craniosynostosis phenotype with scaphocephaly and a particularly severe trigonocephaly. Molecular analysis revealed a missense mutation in the MSX2-associated with the Boston-type craniosynostosis syndrome-affecting the same amino-acid residue as in the original Boston family. Besides unique features such as the cranial sutures involved, minor limb abnormalities and incomplete penetrance, our patients share with the original family autosomal dominant inheritance and the presence of multiple endocranial erosions on CT imaging. Though these findings appear to be important diagnostic clues for MSX2-related craniosynostosis, it is noteworthy that the first affected generation in this family presented merely with isolated sagittal or unicoronal craniosynostosis and cutaneous syndactyly. Molecular analysis of MSX2 should therefore be considered in patients with isolated scaphocephaly/unicoronal synostosis, especially in the presence of a family history for craniosynostosis or syndactyly.

Craniosynostosis: imaging review and primer on computed tomography

Craniosynostosis is encountered in the pediatric population in isolated or syndromic forms. The resulting deformity depends on the number and type of sutures involved and, in multi-sutural synostosis, the order of suture fusion. Primary craniosynostosis needs to be differentiated from the secondary variety and positional or deformational mimics. Syndromic craniosynostoses are associated with other craniofacial deformities. Evaluation with 3-D CT plays an important role in accurate diagnosis and management; however, implementation of appropriate CT techniques is essential to limit the radiation burden in these children. In this article, the authors briefly review the classification, embryopathogenesis and epidemiology and describe in detail the radiologic appearance and differential diagnoses of craniosynostosis.

Validity of the 3D VECTRA photogrammetric surface imaging system for cranio-maxillofacial anthropometric measurements

PURPOSE

The use of three-dimensional (3D) photography for anthropometric measurements is of increasing interest, especially in the cranio-maxillofacial field. Before standard implementation, accurate determination of the precision and accuracy of each system is mandatory.

METHODS

A mannequin head was labelled with 52 landmarks, and 28 three-dimensional images were taken using a commercially available five-pod 3D photosystem (3D VECTRA; Canfield, Fairfield, NJ) in different head positions. Distances between the landmarks were measured manually using a conventional calliper and compared with the digitally calculated distances acquired from labelling by two independent observers. The experimental set-up accounted for clinical circumstances by varying the positioning (vertical, horizontal, sagittal) of the phantom.

RESULTS

In the entire calliper measurement data set (n = 410), a significant difference (p = 0.02) between the directly measured and corresponding virtually calculated distances was found. The mean aberration between both modalities covering all data was 7.96 mm. No differences (p = 0.94) between the two groups were found using a cut-off of 10 % (leaving n = 369 distances) due to considerable errors in direct measurements and the necessary manual data translation. The mean diversity of both measurement modalities after cut-off was 1.33 mm (maximum, 6.70 mm). Inter-observer analysis of all 1,326 distances showed no difference (p = 0.99; maximal difference, 0.58 mm) in the digital measurements.

CONCLUSION

The precision and accuracy of this five-pod 3D photosystem suggests its suitability for clinical applications, particularly anthropometric studies. Three-hundred-and-sixty degree surface-contour mapping of the craniofacial region within milliseconds is particularly useful in paediatric patients. Proper patient positioning is essential for high-quality imaging.

3D of Brain Shape and Volume After Cranial Vault Remodeling Surgery for Craniosynostosis Correction in Infants

The skull of young children is made up of bony plates that enable growth. Craniosynostosis is a birth defect that causes one or more sutures on an infant's skull to close prematurely. Corrective surgery focuses on cranial and orbital rim shaping to return the skull to a more normal shape. Functional problems caused by craniosynostosis such as speech and motor delay can improve after surgical correction, but a post-surgical analysis of brain development in comparison with age-matched healthy controls is necessary to assess surgical outcome. Full brain segmentations obtained from pre- and post-operative computed tomography (CT) scans of 8 patients with single suture sagittal (n=5) and metopic (n=3), non-syndromic craniosynostosis from 41 to 452 days-of-age were included in this study. Age-matched controls obtained via 4D acceleration-based regression of a cohort of 402 full brain segmentations from healthy controls magnetic resonance images (MRI) were also used for comparison (ages 38 to 825 days). 3D point-based models of patient and control cohorts were obtained using SPHARM-PDM shape analysis tool. From a full dataset of regressed shapes, 240 healthy regressed shapes between 30 and 588 days-of-age (time step = 2.34 days) were selected. Volumes and shape metrics were obtained for craniosynostosis and healthy age-matched subjects. Volumes and shape metrics in single suture craniosynostosis patients were larger than age-matched controls for pre- and post-surgery. The use of 3D shape and volumetric measurements show that brain growth is not normal in patients with single suture craniosynostosis.

A genome-wide association study identifies susceptibility loci for nonsyndromic sagittal craniosynostosis near BMP2 and within BBS9

Sagittal craniosynostosis is the most common form of craniosynostosis, affecting approximately one in 5,000 newborns. We conducted, to our knowledge, the first genome-wide association study for nonsyndromic sagittal craniosynostosis (sNSC) using 130 non-Hispanic case-parent trios of European ancestry (NHW). We found robust associations in a 120-kb region downstream of BMP2 flanked by rs1884302 (P = 1.13 × 10(-14), odds ratio (OR) = 4.58) and rs6140226 (P = 3.40 × 10(-11), OR = 0.24) and within a 167-kb region of BBS9 between rs10262453 (P = 1.61 × 10(-10), OR = 0.19) and rs17724206 (P = 1.50 × 10(-8), OR = 0.22). We replicated the associations to both loci (rs1884302, P = 4.39 × 10(-31) and rs10262453, P = 3.50 × 10(-14)) in an independent NHW population of 172 unrelated probands with sNSC and 548 controls. Both BMP2 and BBS9 are genes with roles in skeletal development that warrant functional studies to further understand the etiology of sNSC.

Anterior plagiocephaly: epidemiology, clinical findings,diagnosis, and classification. A review

INTRODUCTION

Anterior plagiocephaly due to the early unilateral fusion of the coronal suture is associated to a clinical phenotype characterized by the unilateral flattening of the frontal bone and the orbit and by the distortion and maldevelopment of adjacent cranial and facial bones. Homolateral anterior displacement of the ear and contralateral deviation of the nasal pyramid and mandible are other prominent clinical features. The differential diagnosis includes a variety of conditions characterized by facial asymmetry, namely, due to muscular alterations, anomalies of the visual function, congenital anomalies of the cervical spine and craniovertebral junction, abnormal pregnancy, and birth injuries. Anterior plagiocephaly is the direct cause of oculomotor anomalies, with a characteristic strabismus, and of progressive asymmetrical maldevelopment of the face, craniovertebral junction, and cervical spine.

METHODS

The medical literature was reviewed in regard to the epidemiology, clinical features, and radiological findings. Different categorization of the affected infants in specific subtypes according to the severity of the condition was analyzed. The aim was to contribute to a practical clinical classification to be utilized for the surgical indication and for predicting the prognosis according to the severity of the condition at presentation.

CONCLUSIONS

Anterior plagiocephaly represents the most challenging simple suture craniosynostosis. The clinical differential diagnosis with other forms of cranial asymmetry is possible on the grounds of mere clinical findings. A classification system is necessary not only for the establishment of surgical planning but also to predict the late cosmetic and functional outcomes.

Nonsyndromic craniosynostosis

Nonsyndromic craniosynostosis is more commonly encountered than syndromic cases in pediatric craniofacial surgery. Affected children display characteristic phenotypes according to the suture or sutures involved. Restricted normal growth of the skull can lead to increased intracranial pressure and changes in brain morphology, which in turn may contribute to neurocognitive deficiency. Management has primarily focused on surgical correction of fused sutures prior to 12 months of age to optimize correction of the deformity and to ameliorate the effects of increased intracranial pressure. However, emphasis has recently shifted to better understanding the pathogenesis of neurocognitive impairment observed in these children, along with genetic mutations that contribute to premature suture fusion. Such understanding will provide opportunities for earlier and more specific neurocognitive interventions and for the development of targeted genetic therapy to prevent pathologic suture fusion. The authors review the common types of nonsyndromic craniosynostosis and the epidemiological, genetic, and neurodevelopmental details that are currently known from the literature. In addition, they present the rationale for surgical correction, offer suggestions for timing of intervention, and present some nuances of techniques that they find important in producing consistent results.

Development of secondary unilateral coronal suture synostosis with a sagittal suture synostosis in a nonsyndromic patient

Multiple-suture synostosis is typically associated with syndromic craniosynostosis but has been occasionally reported in large series of nonsyndromic children. The diagnosis of multiple fused sutures usually occurs at the same time, but rarely has the chronological development of a secondary suture synostosis been noted. The development of secondary bicoronal suture synostosis requiring surgical intervention has only been reported, to date, after surgical intervention and is hypothesized to arise from a disruption of inhibitory factors from the dura. The disinhibition of these factors permits the sutures to then fuse at an early stage. The authors report on a patient who developed secondary unilateral coronal synostosis after the diagnosis of an isolated sagittal synostosis. The secondary synostosis was identified at the time of the initial surgical intervention and ultimately required a second procedure of a frontoorbital advancement. The clinical appearance of this phenomenon may be subtle, and surgeons should monitor for the presence of secondary synostosis during surgery as it may require intervention. Failure to identify the secondary synostosis may necessitate another surgery or result in a poor cosmetic outcome. The authors recommend close clinical follow-up for the short term in patients with isolated sagittal synostosis.

Risk factors associated with craniosynostosis: a case control study

BACKGROUND

Craniosynostosis is a relatively common congenital abnormality. The underlying etiology and most probable risk factors of nonsyndromic craniosynostosis are unknown. We conducted a study to identify the risk factors for craniosynostosis.

MATERIALS AND METHODS

In this case-control project, 70 children with craniosynostosis (syndromic or nonsyndromic) hospitalized at the Children's Hospital Medical Center from September 2010 to 2011 were studied for the potential risk factors. At the same time, 70 age- and sex-matched children hospitalized with other congenital anomalies were reviewed. Information from case and control groups was obtained via personal interviews with parents of patients and a prepared checklist was filled out for each child.

RESULTS

The mean (±SE) age at admission time in the case-control group was 13 ± 1.95 (1.5-96) months, and almost half of them were boys (n = 37 or 53%). The most frequent sutures involved in craniosynostosis were coronal (n = 30 or 42.9%) and then metopic sutures (n = 16 or 22.9%), multiple (n = 12 or 17.1%), sagittal (n = 11 or 15.7%) and lambdoid (n = 1 or 1.4%). In the case group, maternal diabetes mellitus and thyroid disease were found in 8 (11.6%) and 6 (8.6%) patients, respectively. The most frequent medication used by mothers (n = 66 or 94%) in the case group during pregnancy were vitamins (including iron supplements, omega 3, folic acid and multivitamins).

CONCLUSION

A positive family history of craniosynostosis [odds ratio (OR) 19.01 and 95% confidence interval (CI) 2.24-160.7] and using clomiphene citrate for infertility (OR 12.71 and 95% CI 1.42-113.6) were the strongest independent risk factors for craniosynostosis. More comprehensive studies with a larger sample size are required to confirm the role of environmental factors in order to decrease the occurrence of craniosynostosis.