Role of parental risk factors in the aetiology of isolated non-syndromic metopic craniosynostosis

Craniosynostosis in Isfahan, Iran: A Cross-Sectional Study

Background

Craniosynostosis is the premature closure of cranial sutures. According to the literature, several factors are related to this disorder. Due to the relatively high prevalence in Iran and a lack of related studies in this region, this study was designed to determine the characteristics of a group of these patients in this region.

Methods

This cross-sectional study was performed from 2016 to 2019 at two tertiary referral hospitals for children in Isfahan, Iran. Studied variables included: age, sex, birth weight, type of craniosynostosis, concurrent anomalies, parents' age, father's job, fetus position, maternal parity, history of maternal smoking during the pregnancy, use of fertility assistant treatments, and history of maternal endocrine disorders.

Results

We had 125 infants, including 82 (65.6%) males and 43 (34.4%) females. The most common type was metopic (29%). The most common concurrent disorder was congenital heart defects (43.2% of patients). The mean age of infants was 0.62SD0.59 years. Gender distribution showed a significant difference (p value = 0.006). While the metopic (n = 31) type was significantly more common in boys, the coronal type was female predominant (n = 14). The mean age of fathers was 33.08SD5.66 and mothers, was 29.02SD5.70 with no significant difference (p value = 0.669 and 0.149, respectively). Other evaluated factors also didn't show a significant difference.

Conclusion

Craniosynostosis is more prevalent in boys, especially the metopic type. Coronal type has a female predilection. The most common subtype is metopic. The most common concurrent congenital disorder is congenital heart defects.

Correlation Between Demographic Variables and Complications in Nonsyndromic Craniosynostosis

PURPOSE

This retrospective cross-sectional, observational study aims to determine the correlation between demographic variables and nonsyndromic craniosynostosis.

METHODS

A cross-sectional study was carried out. The inclusion criteria were nonsyndromic craniosynostosis and the exclusion criteria were patients who did not have complete records.

RESULTS

The sample included 49 patients and mainly women. Patients with more than 4 days in the intensive care unit were related with more complications. Intracranial Hypertension was seen predominantly in patients between 6 and 8 months P =0007.

CONCLUSION

Some variables can modificate complications risk but future studies are needed to further investigate the influence of such variables on craniofacial care.

Epidemiology, Genetics, and Pathophysiology of Craniosynostosis

Craniosynostosis, the premature fusion of the infant cranial skulls, can be recognized by characteristic head shape differences that worsen with head growth. Craniosynostosis can be syndromic or nonsyndromic and can involve one suture or multiple sutures. Timely cranial vault surgery is recommended to expand and reshape the skull, with a goal of preventing increased intracranial pressure and providing sufficient space for brain growth. Several gene variants and environmental exposures are known to increase the risk of single suture craniosynostosis (SSC), including in utero constraint, exposure to specific toxins and medications, and medical conditions such as thyroid dysregulation and metabolic bone disorders.

Polycystin‐1 regulates cell proliferation and migration through AKT/mTORC2 pathway in a human craniosynostosis cell model

Craniosynostosis is the premature fusion of skull sutures and has a severe pathological impact on childrens’ life. Mechanical forces are capable of triggering biological responses in bone cells and regulate osteoblastogenesis in cranial sutures, leading to premature closure. The mechanosensitive proteins polycystin‐1 (PC1) and polycystin‐2 (PC2) have been documented to play an important role in craniofacial proliferation and development. Herein, we investigated the contribution of PC1 to the pathogenesis of non‐syndromic craniosynostosis and the associated molecular mechanisms. Protein expression of PC1 and PC2 was detected in bone fragments derived from craniosynostosis patients via immunohistochemistry. To explore the modulatory role of PC1 in primary cranial suture cells, we further abrogated the function of PC1 extracellular mechanosensing domain using a specific anti‐PC1 IgPKD1 antibody. Effect of IgPKD1 treatment was evaluated with cell proliferation and migration assays. Activation of PI3K/AKT/mTOR pathway components was further detected via Western blot in primary cranial suture cells following IgPKD1 treatment. PC1 and PC2 are expressed in human tissues of craniosynostosis. PC1 functional inhibition resulted in elevated proliferation and migration of primary cranial suture cells. PC1 inhibition also induced activation of AKT, exhibiting elevated phospho (p)‐AKT (Ser473) levels, but not 4EBP1 or p70S6K activation. Our findings indicate that PC1 may act as a mechanosensing molecule in cranial sutures by modulating osteoblastic cell proliferation and migration through the PC1/AKT/mTORC2 cascade with a potential impact on the development of non‐syndromic craniosynostosis.

The Effect of Using In Vitro Fertilization (IVF) on Increasing the Prevalence of Craniosynostosis

BACKGROUND

Craniosynostosis, a malformation caused by premature closure of one or more cranial sutures, is a rare congenital disability usually of unknown cause; however, it is often associated with assisted reproductive technology. Given the increasing prevalence of craniosynostosis and the use of the in vitro fertilization (IVF) method, the authors evaluated the association between IVF and the prevalence of craniosynostosis.

METHODS

This retrospective study reviewed records of patients with nonsyndromic craniosynostosis who underwent surgery in Mofid Hospital, a tertiary children's hospital affiliated to Shahid Beheshti University of Medical Sciences, between 2010 and 2019.

RESULTS

A total of 200 patients aged one month to 7 years old, were evaluated. Out of 200 patients, 43% were plagiocephalic, 39% trigonocephalic, 8.5% scaphocephalic, 8% brachiocephalic, and 1.5% were mixed. Nine (4.5%) patients had received clomiphene citrate. Eight (4%) mothers had become pregnant under IVF, and they all had used clomiphene citrate for ovulation stimulation. No use of artificial insemination was reported. Of the eight patients whose mother had become pregnant through IVF, three were trigonocephalic, and five were plagiocephalic.

CONCLUSIONS

Without a control group, we are not able report the statistical results confirming or denying a link between craniosynostosis and infertility treatment. However, 4% prevalence of IVF use among craniosynostosis patients is significant. Further studies with a broader statistical community are suggested in this regard.

Nonsyndromic Craniosynostosis Is Associated with Increased Risk for Psychiatric Disorders

BACKGROUND

Craniosynostosis is one of the most common craniofacial malformations demanding surgical treatment in infancy. Data on overall psychiatric morbidity among children with nonsyndromic craniosynostosis remain limited. This study investigated the risk of psychiatric disorders in nonsyndromic craniosynostosis.

METHODS

The authors reviewed a register-based cohort of all individuals born with nonsyndromic craniosynostosis in Sweden between 1973 to 1986 and 1997 to 2012 (n = 1238). The nonsyndromic craniosynostosis cohort was compared with a matched community cohort (n = 12,380) and with unaffected full siblings (n = 1485). The authors investigated the risk of psychiatric disorders, suicide attempts, and suicides by using Cox regression adjusted for perinatal and somatic factors, season and birth year, sex, parental socioeconomic factors, and parental psychiatric disorders.

RESULTS

Children with nonsyndromic craniosynostosis had a higher risk of any psychiatric disorder (adjusted Cox-derived hazard ratio, 1.70; 95 percent CI, 1.43 to 2.02), including intellectual disability (adjusted Cox-derived hazard ratio, 4.96; 95 percent CI, 3.20 to 7.70), language disorders (adjusted Cox-derived hazard ratio, 2.36; 95 percent CI, 1.57 to 3.54), neurodevelopmental disorders (adjusted Cox-derived hazard ratio, 1.30; 95 percent CI, 1.01 to 1.69), and other psychiatric disorders (adjusted Cox-derived hazard ratio, 1.43; 95 percent CI, 1.11 to 1.85). Full siblings with nonsyndromic craniosynostosis were more likely, in the crude analyses, to be diagnosed with any psychiatric disorder, including intellectual disability, language disorders, and neurodevelopmental disorders compared with nonaffected siblings. The higher risk for any psychiatric disorder and intellectual disability remained after adjusting for confounders.

CONCLUSIONS

Children with nonsyndromic craniosynostosis demonstrated higher risks of any psychiatric disorder compared with children without nonsyndromic craniosynostosis. This risk cannot fully be explained by familial influences (i.e., genetic or environmental factors).

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Orbito-facial dysmorphology in patients with different degrees of trigonocephaly severity: quantitative morpho-volumetric analysis in infants with non-syndromic metopic craniosynostosis

PURPOSE

Craniofacial dysmorphology varies significantly along a wide spectrum of severity in metopic cranial synostosis (MCS). This study aimed to quantify craniofacial changes, in MCS, to investigate their relationships with the severity of trigonocephaly.

METHODS

By combining the metopic ridge and interfrontal angles, we identified three groups of trigonocephaly severity (mild group n.14, moderate group n.19, severe group n.18). We perform a quantitative analysis using high-resolution CT images evaluating (1) cranial fossae dimensions; (2) vault indices and ratios: interparietal/ intercoronal (IPD/ICD), interparietal/intertemporal (IPD/ITD), cephalic index, vertico-longitudinal index; (3) orbito-facial distances (midfacial depth, maxillary height, upper facial index, orbital distances, globe protrusions), maxilla and orbital volumes; (4) supratentorial (ICV) and infratentorial (PCFV) cranial volumes and supratentorial (WBV) and infratentorial (PCFBV) brain volumes.

RESULTS

In all groups, middle skull base lengths and upper midface index were increased. In moderate and severe groups: anterior hemifossa lengths were reduced, IPD/ICD and vertico-longitudinal index were changed; midfacial depth, anterior, mild, and lateral interorbital distances were reduced; globe protrusions were increased. The comparison between moderate and severe groups showed an increase of both globe protrusions and IPD/ICD. Among all groups, ICV and WBV were reduced in the severe group.

CONCLUSION

This morpho-volumetric study provides new insights in understanding the craniofacial changes occurring in infants at different severity of trigonocephaly. The increase of globe protrusions and the reduction of supratentorial volumes found in the severe group reflect the severity of trigonocephaly; these findings might have a clinical and surgical relevance.

Characterization of Perinatal Risk Factors and Complications Associated With Nonsyndromic Craniosynostosis

BACKGROUND

Certain intrauterine risk factors are known to increase the risk of premature cranial suture fusion and may cause complications during birth. Some of these risk factors may be modifiable. Therefore, the authors sought to characterize the institutional patterns of prenatal risk factors and perinatal complications in nonsyndromic craniosynostosis patients compared to normal births from the surrounding area to identify areas for possible intervention or prevention.

METHODS

The medical records of all infants with nonsyndromic craniosynostosis and full birth records born at Duke University Health System from 2006 to 2017 were retrospectively reviewed. Maternal comorbidities, prenatal risk factors, and perinatal complications were collected. The North Carolina State Center for Health Statistics was queried for perinatal statistics from Durham county and the Northeastern Perinatal Care Region to represent a control cohort of normal births from the same time period and region. The primary outcome investigated was the incidence of prenatal risk factors and complications at birth associated with premature fusion of cranial sutures.

RESULTS

Eighty births with nonsyndromic craniosynostosis were included in this study. The majority of these patients were males (61.7%) and born via cesarean section (55.0%). Intrauterine growth restriction occurred in 10.0% and head trauma during delivery occurred in 2.5%. Twinning (14.8% vs 3.6%, P < 0.0001), cesarean births (55.5% vs 30.0%, P < 0.0001), and breech presentation (17.3% vs 3.2%, P < 0.0001) were significantly more common in craniosynostosis patients. Prenatally, mothers of craniosynostosis infants had higher incidence of gestational diabetes (13.5% vs 5.0%, P < 0.0001) and oligohydramnios (6.1% vs 1.3%, P < 0.0001) compared to regional controls.

CONCLUSION

This study demonstrates that premature suture fusion is associated with prenatal risk factors such as gestational diabetes and oligohydramnios. Continued research into potentially modifiable prenatal risk factors and more refined prenatal diagnostic tools has the potential to reduce both the incidence of premature suture fusion and the sequelae of birth complications in this population.

Multicentre approach to epidemiological aspects of craniosynostosis in Germany

We know of no current published data on the prevalence of craniosynostosis in Germany, so our objective in this study was to contribute to the limited knowledge of its epidemiology by assessing time trends, the frequency of prenatal diagnosis, and the timing of diagnosis and treatment. Data were collected in Saxony-Anhalt during the period 2000-17, and we designed a retrospective multicentre cohort study. The prevalence was 4.8 cases of craniosynostosis/10 000 births, and did not increase during that time. We compared the data of 91 patients with those of 273 controls. There were 75 boys and 16 girls (ratio 4.7:1). Fifty-one children had isolated craniosynostosis, consisting of 46 with a single-suture, and five with a multisuture, synostosis. Twenty-nine were associated with other congenital malformations, and 11 were syndromic. Three cases had been diagnosed prenatally, and 34 had skull deformities diagnosed immediately after birth at a mean (SD) age of 3.4 (4.7) months. The mean (SD) age at the time of first admission to hospital in one of the three surgical centres of Saxony-Anhalt was 5.9 (5.5) months, and 65 patients were operated on at a mean age of 9.1 (6.3) months. In contrast to published reports we found a prevalence of 4.8 cases of craniosynostosis/10 000 births that did not increase during the period 2000-16. Although we found a low prenatal detection rate, the diagnosis and treatment in this cohort study seemed timely.

Fibroblast Growth Factor Receptor 2 (FGFR2) Mutation Related Syndromic Craniosynostosis

Craniosynostosis results from the premature fusion of cranial sutures, with an incidence of 1 in 2,100-2,500 live births. The majority of cases are non-syndromic and involve single suture fusion, whereas syndromic cases often involve complex multiple suture fusion. The fibroblast growth factor receptor 2 (FGFR2) gene is perhaps the most extensively studied gene that is mutated in various craniosynostotic syndromes including Crouzon, Apert, Pfeiffer, Antley-Bixler, Beare-Stevenson cutis gyrata, Jackson-Weiss, Bent Bone Dysplasia, and Seathre-Chotzen-like syndromes. The majority of these mutations are missense mutations that result in constitutive activation of the receptor and downstream molecular pathways. Treatment involves a multidisciplinary approach with ultimate surgical fixation of the cranial deformity to prevent further sequelae. Understanding the molecular mechanisms has allowed for the investigation of different therapeutic agents that can potentially be used to prevent the disorders. Further research efforts are need to better understand screening and effective methods of early intervention and prevention. Herein, the authors provide a comprehensive update on FGFR2-related syndromic craniosynostosis.

Craniosynostosis

Craniosynostosis is the premature fusion of one or more of the cranial sutures. About 8% of the patients have familial or syndromic forms of synostosis, and in the remainder it occurs as a spontaneous isolated defect. Familial craniosynostosis syndromes are typically transmitted as an autosomal dominant trait resulting in disruption of the fibroblast growth factor receptor pathway. Familiarity with the characteristic head shapes resulting from craniosynostosis allows bedside diagnosis and differentiation from positional plagiocephaly. Because of the risks associated with untreated craniosynostosis, surgical treatment is usually undertaken soon after diagnosis. Current surgical methods include open calvarial reconstruction, minimally invasive strip craniectomy with use of postoperative molding helmet, minimally invasive strip craniectomy with spring implantation, and cranial distraction. Early referral to a pediatric craniofacial center allows all treatment options to be explored.

Full length articles published in BJOMS during 2010-11--an analysis by sub-specialty and study type

Full length articles such as prospective and retrospective studies, case series, laboratory-based research and reviews form the majority of papers published in the British Journal of Oral and Maxillofacial Surgery (BJOMS). We were interested to evaluate the breakdown of these types of articles both by sub-specialty and the type of study as well as the proportion that are written by UK colleagues compared to overseas authors over a 2 year period (2010-11). A total of 191 full length articles across all sub-specialties of our discipline were published, with 107 papers (56%) coming from UK authors. There were proportionately more oncology papers arising from the UK than overseas (60 and 30% of total respectively) while the opposite was found for cleft/deformity studies (10% and 22%). There was only one laboratory-based study published from the UK compared with 27 papers from overseas. The number of quality papers being submitted to the Journal continues to increase, and the type of article being published between UK and overseas probably reflects different practices and case-loads amongst colleagues. The relatively few UK laboratory based studies published in BJOMS compared to overseas authors are most likely due to authors seeking the most prestigious journals possible for their work.

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.

A previously undescribed de novo 4p15 deletion in a patient with apparently isolated metopic craniosynostosis

Interstitial deletion of the short arm of chromosome 4, excluding cytoband p16, has been described as a distinct phenotype from the Wolf-Hirschhorn syndrome, characterized by a deletion encompassing cytoband p16. We report on the case of a 14-month-old boy with an apparently isolated craniosynostosis and harboring a de novo microdeletion in band 4p15. The imbalance, about 4 Mb in size is, to date, the smallest deletion ever described in this region, encompassing 12 genes. A comparison with other previously described cases of 4p15 deletion is made, and the possible roles of some genes involved in the deletion are discussed.