Abnormal cerebellar structure is dependent on phenotype of isolated cleft of the lip and/or palate

White matter tract integrity in isolated oral clefts: relationship to cognition and reading skills

Children with isolated cleft of the lip and/or palate (iCL/P) have been shown to be at risk for impaired reading ability. Structural and functional neuroimaging studies have revealed subtle morphological and functional abnormalities correlated to cognition and reading ability. However, the integrity of white matter tracts and their potential relationship to reading performance in iCL/P is under-studied. The purpose of the present study was to evaluate white matter integrity related to cognition and reading skills among participants with and without iCL/P. Data from two cross-sectional, case/control studies with similar neuropsychological batteries and diffusion tensor imaging (DTI) protocols were combined. The final sample included 210 participants (ages 7 to 27 years). Group and sex differences in fractional anisotropy (FA) values were examined between participants with (n = 105) and without (n = 105) iCL/P. Potential associations between FA values and age, cognition, and reading skills were also evaluated separately by group and sex. Sex effects were prominent in association and projection fibers, and effects of cleft status were found in association fibers and cerebellar regions, with isolated associations to reading skills. Findings provide preliminary understanding of microstructural associations to cognitive and reading performance among children, adolescents, and young adults with iCL/P.

The Brain in Oral Clefting: A Systematic Review With Meta-Analyses

Background

Neuroimaging of individuals with non-syndromic oral clefts have revealed subtle brain structural differences compared to matched controls. Previous studies strongly suggest a unified primary dysfunction of normal brain and face development which could explain these neuroanatomical differences and the neuropsychiatric issues frequently observed in these individuals. Currently there are no studies that have assessed the overall empirical evidence of the association between oral clefts and brain structure. Our aim was to summarize the available evidence on potential brain structural differences in individuals with non-syndromic oral clefts and their matched controls.

Methods

MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, Web of Science and Embase were systematically searched in September 2020 for case-control studies that reported structural brain MRI in individuals with non-syndromic oral clefts and healthy controls. Studies of syndromic oral clefts were excluded. Two review authors independently screened studies for eligibility, extracted data and assessed risk of bias with the Newcastle-Ottawa Scale. Random effects meta-analyses of mean differences (MDs) and their 95% confidence intervals (95% CI) were performed in order to compare global and regional brain MRI volumes.

Results

Ten studies from 18 records were included in the review. A total of 741 participants were analyzed. A moderate to high risk of bias was determined for the included studies. The cerebellum (MD: -12.46 cm³, 95% CI: -18.26, -6.67, n = 3 studies, 354 participants), occipital lobes (MD: -7.39, 95% CI: -12.80, -1.99, n = 2 studies, 120 participants), temporal lobes (MD: -10.53 cm³, 95% CI: -18.23, -2.82, n = 2 studies, 120 participants) and total gray matter (MD: -41.14 cm³; 95% CI: -57.36 to -24.92, n = 2 studies, 172 participants) were significantly smaller in the cleft group compared to controls.

Discussion

There may be structural brain differences between individuals with non-syndromic oral clefts and controls based on the available evidence. Improvement in study design, size, methodology and participant selection could allow a more thorough analysis and decrease study heterogeneity.

Mechanical Tension-Stress in Alveolar Cleft Repaired With Autogenous Bone in Canine Models

OBJECTIVE

Cleft lip and/or palate is a common birth defect worldwide, always accompanied by alveolar cleft. However, the success rate of secondary alveolar bone grafting is unsatisfactory. Rapid maxillary expansion (RME) often used after bone transplantation provides functional stimulation for bone graft area. This study aimed to investigate the effect of RME force on the bone graft area and midpalatal suture, and screen out the most suitable loaded force and loaded teeth, so as to provide a reference for clinical treatment.

METHODS

Fourteen 24-week-old male beagles were assigned randomly to 3 groups: blank control, autogenous, and autogenous with RME. Three-dimensional finite element analysis was conducted to evaluate the distribution and value of the stress in the model. The maxillae were collected and subjected to radiography and helical computed tomography to evaluate new bone formation in the graft area. Van Gieson's Picrofuchsin staining was performed for histomorphological observation.

RESULTS

After 8 weeks of RME treatment, new bone formation of the dogs was markedly accelerated, and bone resorption was significantly reduced compared with the untreated dogs or those only treated with autogenous iliac bone. The treatment with RME evidently made the bone trabecula more abundant and the area of bone formation larger. Three-dimensional finite element analysis showed that the clinical effect can be achieved by using canine teeth as the loaded teeth and applying force of 10 MPa.

CONCLUSION

Rapid maxillary expansion after bone grafting had a positive effect on osteogenesis in a canine model of alveolar cleft.

Home Language Environment of Children With Orofacial Clefts as a Target for Intervention

OBJECTIVE

To evaluate the home language environment (HLE) in children with orofacial clefts as a potential modifiable target for language and literacy intervention.

DESIGN

Feasibility study examining longitudinal trends in HLE and responses to parent-focused literacy intervention.

SETTING

Tertiary care children's hospital.

PARTICIPANTS

HLE data were collected for 38 children with orofacial clefts between ages 7 and 23 months. Twenty-seven participants received parent-focused literacy intervention.

INTERVENTIONS

Reach Out and Read, a literacy intervention, was introduced during a clinic visit. To assess response, participants were randomized to age at intervention (9, 18, or 24 months).

MAIN OUTCOME MEASURES

Primary outcome measures included measurements from recordings in the home language environment of adult word count, child vocalizations, and conversational turns.

RESULTS

Baseline (preintervention) results showed lower adult word count and conversational turns for caregivers and children with cleft lip and palate, as well as for those from lower socioeconomic groups. After the literacy intervention was introduced, this cohort showed increasing measures of child and caregiver vocalizations, particularly when introduced at 18 months.

CONCLUSIONS

Although these results are preliminary, findings suggest that HLE characteristics vary as a function of children's cleft type as well as family socioeconomic status. Further, our caregiver-focused literacy intervention was feasible and resulted in short-term improvements in HLE. This is the first study to document HLE as a target for intervention in children with oral clefts. These findings support further research on HLE and caregiver-focused intervention to improve language/literacy outcomes for children with oral clefts.

Articulation rehabilitation induces cortical plasticity in adults with non-syndromic cleft lip and palate

In this study, we investigated brain morphological changes in adults with non-syndromic cleft lip and palate (NSCLP) after articulation rehabilitation (AR). High-resolution T1 weighted brain magnetic resonance imaging data were analyzed from 45 adults with NSCLP after palatoplasty: 24 subjects were assessed before AR (bNSCLP) and 21 subjects were assessed after AR (aNSCLP). In addition, there were 24 age and sex matched controls. Intergroup differences of grey matter volume were evaluated as a comprehensive measure of the cortex; cortical thickness and cortical complexity (gyrification and fractal dimensions) were also analyzed. As compared to controls, the bNSCLP subjects exhibited altered indexes in frontal, temporal, and parietal lobes; these morphological changes are characteristic for adults with NSCLP. Importantly, as compared to the bNSCLP and control subjects, the aNSCLP subjects exhibited cortical plasticity in the regions involved in language, auditory, pronunciation planning, and execution functions. The AR-mediated cortical plasticity in aNSCLP subjects may be caused by AR-induced cortical neurogenesis, which might reflect the underlying neural mechanism during AR.

[Formula: see text] Neuropsychological functioning and its relationship with brain anatomical measures of children and adolescents with non-syndromic cleft lip and palate

BACKGROUND

Children and adolescents with non-syndromic cleft lip and palate (NSCLP) show cognitive performance below expected. This difficulty can be associated with alterations in the cortical thickness and volume of brain regions. The aim of this study was to investigate anatomical brain characteristics and their relationship with the neuropsychological scores of children and adolescents with NSCLP. Methods: Twenty-four children and adolescents with ages from 10 to 16 years and 11 months (12 with a diagnosis of NSCLP; 12 with typical development) were enrolled. Neuropsychological tests were administered and high-resolution, structural magnetic resonance imaging (MRI) was performed in a 1.5 T scanner. Results: Compared to the control group, NSCLP individuals showed intellectual (p = 0.006) and cognitive (p = 0.003) impairment, as well as deficits in subdomains of executive functions (sustained attention, working memory, and cognitive planning). The morphological analysis showed reduced volumes and cortical thickness in temporal, parietal, and frontal regions, in both hemispheres, of the NSCLP group. Significant, strong associations of structural alterations and cognitive performance were observed. Conclusions: Our study provided strong evidence of the relationship between brain development in children and adolescents with NSCLP, and their neuropsychological profile. This relationship is characterized by a malfunction of associative areas of the brain, such as parieto-temporo-occipital, frontoparietal, and prefrontal regions.

Reading Achievement in Boys With Non-Syndromic Cleft Palate Only: Relationship to Neuropsychological Skill and Neurocircuitry

Reading achievement and neural activation during a reading task were evaluated among boys with isolated cleft palate only (iCP) in comparison to unaffected controls. Ten boys with iCP and 10 unaffected boys between the ages of 8 and 16 years old were assessed. Standardized assessments of intelligence and reading achievement were administered and participants underwent a block-design functional magnetic resonance imaging protocol using non-word rhyming and judgment of line tasks. Among the 10 boys with iCP, reading fluency correlated with phonological awareness and visual memory. Neural activation was increased in regions of the brain associated with a non-fluent/dyslexic reading pattern.

Epidemiology, Etiology, and Treatment of Isolated Cleft Palate

Isolated cleft palate (CPO) is the rarest form of oral clefting. The incidence of CPO varies substantially by geography from 1.3 to 25.3 per 10,000 live births, with the highest rates in British Columbia, Canada and the lowest rates in Nigeria, Africa. Stratified by ethnicity/race, the highest rates of CPO are observed in non-Hispanic Whites and the lowest in Africans; nevertheless, rates of CPO are consistently higher in females compared to males. Approximately fifty percent of cases born with cleft palate occur as part of a known genetic syndrome or with another malformation (e.g., congenital heart defects) and the other half occur as solitary defects, referred to often as non-syndromic clefts. The etiology of CPO is multifactorial involving genetic and environmental risk factors. Several animal models have yielded insight into the molecular pathways responsible for proper closure of the palate, including the BMP, TGF-β, and SHH signaling pathways. In terms of environmental exposures, only maternal tobacco smoke has been found to be strongly associated with CPO. Some studies have suggested that maternal glucocorticoid exposure may also be important. Clearly, there is a need for larger epidemiologic studies to further investigate both genetic and environmental risk factors and gene-environment interactions. In terms of treatment, there is a need for long-term comprehensive care including surgical, dental and speech pathology. Overall, five main themes emerge as critical in advancing research: (1) monitoring of the occurrence of CPO (capacity building); (2) detailed phenotyping of the severity (biology); (3) understanding of the genetic and environmental risk factors (primary prevention); (4) access to early detection and multidisciplinary treatment (clinical services); and (5) understanding predictors of recurrence and possible interventions among families with a child with CPO (secondary prevention).

Haploinsufficiency of interferon regulatory factor 6 alters brain morphology in the mouse

Orofacial clefts are among the commonest birth defects. Among many genetic contributors to orofacial clefting, Interferon Regulatory Factor 6 (IRF6) is unique since mutations in this gene cause Van der Woude (VWS), the most common clefting syndrome. Furthermore, variants in IRF6 contribute to increased risk for non-syndromic cleft lip and/or palate (NSCL/P). Our previous work shows that individuals with either VWS or NSCL/P may have cerebral anomalies (larger anterior, smaller posterior regions), and a smaller cerebellum. The objective of this study was to test the hypothesis that disrupting Irf6 in the mouse will result in quantitative brain changes similar to those reported for humans with VWS and NSCL/P. Male mice heterozygous for Irf6 (Irf6(gt1/+); n = 9) and wild-type (Irf6(+/+) ; n = 6) mice at comparable age underwent a 4.7-T MRI scan to obtain quantitative measures of cortical and subcortical brain structures. There was no difference in total brain volume between groups. However, the frontal cortex was enlarged in the Irf6(gt1/+) mice compared to that of wild types (P = 0.028) while the posterior cortex did not differ. In addition, the volume of the cerebellum of Irf6(gt1/+) mice was decreased (P = 0.004). Mice that were heterozygous for Irf6 showed a similar pattern of brain anomalies previously reported in humans with VWS and NSCL/P. These structural differences were present in the absence of overt oral clefts. These results support a role for IRF6 in brain morphometry and provide evidence for a potential genetic link to abnormal brain development in orofacial clefting.