Microtia and Related Facial Anomalies

"Microtia, Branchial Cleft Fistula, and Tetralogy of Fallot: A Possible Association"

When searching over associations between congenital ear abnormalities, especially microtia and affiliated deformities like cleft lip or palate and congenital heart diseases, some clinical analysis and genetic theories are found. A 10-year-old boy sent to the plastic surgery hospital was puzzled by a congenital anterior auricular fistula with fluid trace for more than 9 years. The preoperative diagnoses were branchial cleft fistula and congenital left ear deformity with postoperation of TOF. By browsing over studies on genetic concerns and clinical performance, it may be attributed to a possible association between microtia, branchial cleft fistula, and tetralogy of Fallot, though whose fundamental mechanisms remain concerned.

Electrocardiographic abnormalities in patients with microtia

The main objective of this study was to investigate the incidence and characteristics of electrocardiographic abnormalities in patients with microtia, and to explore cardiac maldevelopment associated with microtia. This retrospective study analyzed a large cohort of microtia patients admitted to Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, from September 2017 to August 2022. The routine electrocardiographic reports of these patients were reviewed to assess the incidence and characteristics of abnormalities. The study included a total of 10,151 patients (5598 in the microtia group and 4553 in the control group) who were admitted to the Plastic Surgery Hospital of Peking Union Medical College. The microtia group had a significantly higher incidence of abnormal electrocardiographies compared to the control group (18.3% vs. 13.6%, P < 0.01), even when excluding sinus irregularity (6.1% vs. 4.4%, P < 0.01). Among the 1025 cases of abnormal electrocardiographies in the microtia group, 686 cases were reported with simple sinus irregularity. After excluding sinus irregularity as abnormal, the most prevalent abnormalities was right bundle branch block (37.5%), followed by sinus bradycardia (17.4%), ST-T wave abnormalities (13.3%), atrial rhythm (9.1%), sinus tachycardia (8.3%), and ventricular high voltage (4.7%). Less common ECG abnormalities included atrial tachycardia (2.1%), ventricular premature contraction (2.4%), and ectopic atrial rhythm (1.8%). atrioventricular block and junctional rhythm were present in 1.2% and 0.9% of the cases, respectively. Wolff Parkinson White syndrome and dextrocardia had a lower prevalence, at 0.6% and 0.9%, respectively. The occurrence of electrocardiographic abnormalities in microtia patients was found to be higher compared to the control group. These findings highlight the potential congenital defect in cardiac electrophysiology beyond the presence of congenital heart defect that coincide with microtia.

Epidemiology of congenital malformations of the external ear in Hunan Province, China, from 2016 to 2020

To describe the epidemiology of congenital malformations of the external ear (CMEE). Data were obtained from the Birth Defects Surveillance System in Hunan Province, China, 2016 to 2020. The prevalence of CMEEs is defined as the number of cases per 1000 fetuses (births and deaths at 28 weeks of gestation and beyond) (unit: ‰). Prevalence and 95% confidence intervals (CI) were calculated by the log-binomial method. Chi-square trend tests (χ2trend) were used to determine trends in prevalence by year. P < .05 was considered statistically significant. Crude odds ratios (ORs) were calculated to examine the association of sex, residence, and maternal age with CMEEs. Our study included 847,755 fetuses, and 14,459 birth defects were identified, including 1227 CMEEs (accounted for 8.49% of birth defects). The prevalences of birth defects and CMEEs were 17.06‰ (95%CI: 16.78-17.33) and 1.45‰ (95%CI: 1.37-1.53), respectively. A total of 185 microtia-anotias were identified, accounting for 15.08% of CMEEs, with a prevalence of 0.22‰ (95%CI: 0.19-0.25). And 1042 other CMEEs were identified, accounting for 84.92% of CMEEs. From 2016 to 2020, the prevalences of birth defects were 18.20‰, 18.00‰, 16.31‰, 16.03‰, and 16.47‰, respectively, showing a downward trend (χ2trend =8.45, P < .01); the prevalences of CMEEs were 1.19‰, 1.62‰, 1.80‰, 1.21‰, and 1.35‰, respectively, with no significant trend (χ2trend =0.09, P = .77). CMEEs were more common in males than females (1.60‰ vs 1.27‰, OR = 1.26, 95%CI: 1.12-1.41), in urban areas than in rural areas (1.77‰ vs 1.23‰, OR = 1.45, 95%CI: 1.29-1.62). The prevalences of CMEEs for maternal age < 20, 20-24, 25-29, 30-34, and ≥ 35 were 1.75‰, 1.27‰, 1.44‰, 1.47‰, and 1.58‰, respectively, with no significant difference (P > .05, reference: 25-29). Most CMEEs were diagnosed by clinical examinations (92.34%), and most CMEEs were diagnosed postpartum (within 7 days) (96.25%). In summary, we have presented the epidemiology of CMEEs in Hunan Province, China. CMEEs were more common in males than females, in urban areas than rural areas, whereas there was no significant difference in prevalence of CMEEs by maternal age. We inferred that CMEEs may be mainly related to genetics, and the mechanism needs to be examined in the future.

Foxi3GFP and Foxi3CreER mice allow identification and lineage labeling of pharyngeal arch ectoderm and endoderm, and tooth and hair placodes

BACKGROUND

FOXI3 is a forkhead family transcription factor that is expressed in the progenitors of craniofacial placodes, epidermal placodes, and the ectoderm and endoderm of the pharyngeal arch region. Loss of Foxi3 in mice and pathogenic Foxi3 variants in dogs and humans cause a variety of craniofacial defects including absence of the inner ear, severe truncations of the jaw, loss or reduction in external and middle ear structures, and defects in teeth and hair.

RESULTS

To allow for the identification, isolation, and lineage tracing of Foxi3-expressing cells in developing mice, we targeted the Foxi3 locus to create Foxi3GFP and Foxi3CreER mice. We show that Foxi3GFP mice faithfully recapitulate the expression pattern of Foxi3 mRNA at all ages examined, and Foxi3CreER mice can trace the derivatives of pharyngeal arch ectoderm and endoderm, the pharyngeal pouches and clefts that separate each arch, and the derivatives of hair and tooth placodes.

CONCLUSIONS

Foxi3GFP and Foxi3CreER mice are new tools that will be of use in identifying and manipulating pharyngeal arch ectoderm and endoderm and hair and tooth placodes.

[Contemporary diagnosis and management of congenital microtia and aural atresia : Part 1: Principles and diagnosis]

Congenital malformations of the pinna and aural atresia can result in major aesthetic and functional deficits. Knowledge about embryologic developments and established classification systems is an essential requirement when dealing with affected patients. Early detection of deficiencies and introduction of appropriate diagnostic measures is vital to initiate adequate therapies and prevent long-term disabilities. Treatment for malformations of the pinna-if requested-is mostly surgical, infrequently an epithesis is applied. As in other surgical fields, tissue engineering will likely play a crucial role in the future. Treatment of aural stenosis and atresia aims at improvement of hearing levels and prevention of secondary complications like cholesteatoma and chronic otorrhea. Auditory rehabilitation comprises a spectrum from conventional hearing aids to invasive hearing implants, the latter being favored in recent years.

The role of MRI in the prenatal diagnosis and classification of fetal microtia

OBJECTIVE

To investigate the role of MRI in the diagnosis and classification of fetal microtia.

METHODS

Ninety-five fetuses with suspected microtia based on ultrasound and MRI performed within 1 week were enrolled in this study. The diagnosis based on MRI was compared with postnatal diagnosis. Among the microtia cases suspected on the basis of MRI, mild and severe cases were further classified. In addition, external auditory canal (EAC) atresia was evaluated by MRI in 29 fetuses with a gestational age > 28 weeks, and the accuracy of MRI in the diagnosis and classification of microtia was determined.

RESULTS

Of 95 fetuses, 83 were considered to have microtia on the basis of MRI, 81 were confirmed to have microtia, and 14 were found to be normal according to postnatal diagnosis. Among 190 external ears in 95 fetuses, 40 ears were suspected to have mild microtia, and 52 ears were suspected to have severe microtia on the basis of MRI. According to the postnatal diagnosis, mild and severe microtia were confirmed in 43 and 49 ears, respectively. Among the 29 fetuses with a gestational age > 28 weeks, 23 ears were suspected to have EAC atresia according to MRI and 21 ears were ultimately confirmed to have EAC atresia. The accuracy of MRI in diagnosing microtia and EAC atresia was 93.68% and 93.10%, respectively.

CONCLUSION

MRI shows good performance in diagnosing fetal microtia and has the potential to evaluate its severity on the basis of classification and EAC status.

CLINICAL RELEVANCE STATEMENT

This study was aimed at investigating the role of MRI in the diagnosis and classification of fetal microtia. MRI shows good performance and can help evaluate microtia severity and EAC atresia, thus allowing for better clinical management.

KEY POINTS

• MRI is a useful adjunct to prenatal ultrasound. • MRI has a higher accuracy rate than ultrasound in diagnosing fetal microtia. • The accurate classification of fetal microtia and the diagnosis of external auditory canal atresia through MRI may help guide clinical management.

National Trends in Microtia Repair Cost and Hospital Length of Stay

Microtia can have deleterious impacts on the functional, psychological, and aesthetic outcomes of affected young children. Reconstructive procedures can alleviate these negative outcomes and significantly improve the quality of life for patients; however, the cost and length of hospital stay (LOS) for such procedures and the factors that impact them have not been well-characterized. This study seeks to understand the hospital-level (institution type, size, and geographic region) and patient-level factors (race, age, and insurance status) that impact cost and LOS in patients who undergo microtia reconstructive surgery. A retrospective data analysis was conducted utilizing the National Inpatient Sample (NIS) database for the years 2008 to 2015. Inclusion criteria included patients who had an International Classification of Diseases, Ninth Revision (ICD-9) diagnostic code for microtia (744.23) as well as a procedure for microtia correction (186×/187×). A total of 714 microtia repair cases met the inclusion criteria and were sampled from the NIS database. Microtia repair cost was significantly increased on the West Coast compared with the Northeast ($34,947 versus $29,222, P =0.020), increased with patient age ($614/y, P =0.012), and gradually increased from 2008 to 2015 ($25,897-$48,985, P <0.001). Microtia LOS was significantly increased with government-controlled hospitals compared with private hospitals (1.93 versus 1.39 d, P =0.005), increased with patients on Medicaid compared with private insurance (2.33 versus 2.00 d, P =0.036), and overall decreased with patient age (-0.07 d/y, P =0.001). The results not only identify the multifactorial impacts that drive cost and LOS in microtia repair but provide insights into the financial and medical considerations patients and their families must navigate.

Functional Pathway and Process Enrichment Analysis of Genes Associated With Morphological Abnormalities of the Outer Ear

Congenital anomalies of the outer ear are common birth defects, including a variety of congenital deformities or malformations ranging from mild structural anomalies to total absence of the ear. Despite its high incidence and detrimental impact on patients, the etiology of outer ear abnormalities remains poorly understood. The goal of this study was to summarize the related genes and improve our understanding of the genetic etiology of morphological abnormalities of the outer ear. Human Phenotype Ontology (HPO) database, Mouse Genome Informatics (MGI) database, and PubMed search engine were used to acquire the genes associated with abnormal human or mouse outer ear. Metascape was employed on the genes above to conduct functional annotation, pathway and process enrichment analysis, protein-protein interaction network analysis, and MCODE component analysis. After a comprehensive review of the databases and literature, we identified 394 human genes and 148 mouse genes that have been associated with abnormal phenotypes of the outer ear, and we identified several biological pathways for human and mouse respectively. Especially, the analysis of common genes shared by human and mouse emphasized the importance of certain genes ( PAX6 , PBX1 , HOXA1 , HOXA2 , TBX1 , TBX15 , PRRX1 , and HMX1 ) in the embryonic development of the external ear. Through our analysis of genes associated with morphological abnormalities of the outer ear, the authors have shown that embryonic development pathways take important roles in the morphogenesis of abnormal external ear and highlighted some potential genetic drivers.

Integrated microtia and aural atresia management

Objectives

To present recommendations for the coordinated evaluation and management of the hearing and reconstructive needs of patients with microtia and aural atresia.

Methods

A national working group of 9 experts on microtia and atresia evaluated a working document on the evaluation and treatment of patients. Treatment options for auricular reconstruction and hearing habilitation were reviewed and integrated into a coordinated care timeline.

Results

Recommendations were created for children with microtia and atresia, including diagnostic considerations, surgical and non-surgical options for hearing management and auricular reconstruction, and the treatment timeline for each option. These recommendations are based on the collective opinion of the group and are intended for otolaryngologists, audiologists, plastic surgeons, anaplastologists, and any provider caring for a patient with microtia and ear canal atresia. Close communication between atresia/hearing reconstruction surgeon and microtia repair surgeon is strongly recommended.

[Antenatal ear examination: When, how and why?]

Antenatal ear examination is an integral part of the thorough examination of the fetal face. The discovery of an anomaly, whether it is made by chance or during a complementary in-depth examination, leads the practitioner to determine its isolated or associated character, in order to characterise its possible belonging to a syndromic entity. In this context, the realization of genetic analysis more precise and wider allowing a return of the results in a time compatible with an evolutive pregnancy, gives to the geneticist a central role in the management of these couples. The main challenge lies in obtaining a set of concordant clinical and biological clues, enabling the genetic results identified to be interpreted correctly, the optimised functioning of the ultrasound practitioner - geneticist duo is therefore fundamental. This results in a complex information to deliver, in the fact that the clinical translation of an ear anomaly in antenatal can go from an isolated aesthetic anomaly to a genetic syndrome with neurodevelopmental disorder. The objective of this work is to describe, from a methodological analysis of antenatal ears, the accessible malformative entities, isolated or associated, and to discuss the problems in the need or not to propose their screening.

Evaluation and Nonsurgical Treatment of Neonatal Ear Anomalies: A Case Report

BACKGROUND

Inspection and evaluation of the neonate's ears are important parts of the neonatal examination. Neonates display a wide variety of ear size and configuration. In many cases, ear molding techniques obviate the need for future surgical correction. This article provides a review of the fetal ear development and describes common physical examination findings of the newborn's external ear. A case report reviews a successful nonsurgical treatment of a minor ear deformity.

CLINICAL FINDINGS

Newborn infant with near absent to very thin bilateral helical rims and otherwise normal bilateral ear shape and structures.

PRIMARY DIAGNOSIS

Bilateral Stahl's ear deformity.

INTERVENTIONS

The EarBuddies product was applied to bilateral ears in an outpatient pediatric plastic surgery clinic. This product remained in place for 8 weeks.

OUTCOMES

The family was pleased with the overall progress and shape of their child's ears. At 18 months of age, the family has no desire to pursue surgical correction of their child's ears.

PRACTICE RECOMMENDATIONS

Assessment of the newborn's external ear is part of a routine admission examination. Careful attention to abnormal or unusual findings allows for prompt evaluation and nonsurgical intervention.

Epidemiological Study of Neonatal Congenital Microtia in Shandong Province, China, 2011-2020

OBJECTIVE

Congenital microtia is a common congenital disease in newborns. The specific cause of congenital microtia is currently unknown. The main objective of this study is to elucidate the epidemiological characteristics of congenital microtia and explore the possible etiology of congenital microtia.

METHODS

Part of the newborn data from 2011 to 2020 in Shandong Province Birth Defects Monitoring Hospitals were randomly selected. The software GraphPad Prism 9 was used to analyze the data and draw figures.

RESULTS

A total of 4247 infants were diagnosed with congenital malformation among 149,525 newborns randomly selected from the Shandong Province Birth Defects Monitoring Hospitals. Among them, a total of 115 infants were diagnosed with congenital microtia. The mean incidence of microtia during 10 years was 76.14±21.93 per 100,000 infants. The mean incidence of microtia in infants with congenital malformation was 2.67±0.75%. The average incidence of male and female infants with microtia during 10 years were 86.93±23.22 and 64.18±32.71 per 100,000 infants, respectively. In terms of maternal age, the older the mother, the higher the incidence of microtia. In terms of the place of residence, rural infants have a higher incidence of microtia than urban infants.

CONCLUSIONS

The average incidence of microtia was 76.14±21.93 per 100,000 infants in Shandong Province, China, 2011-2020. The female-to-male incidence ratio was 1.45:1. The authors recommend that women choose to give birth at the age of 25 to 29. They hope that the government will take measures to improve the medical and health conditions in rural areas and improve parenting knowledge in rural areas. This can effectively reduce the prevalence of microtia in infants.

Association Between Maternal Exposure to SO2 and Congenital Ear Malformations in Offspring: A Population-Based Case-Control Study in Liaoning Province, China

Objectives: To examine associations between maternal sulfur dioxide (SO2) exposure and congenital ear malformations risk in offspring.

Methods: We surveyed 1676 cases with congenital ear malformations and 7950 controls from the Maternal and Child Health Certificate Registry of Liaoning Province between 2010 and 2015. SO2 concentrations were obtained from the Municipal Environment Protection Bureau of Liaoning Province. Multivariable logistic regression models and Restricted cubic splines (RCS) model were used to assess the aforementioned association.

Results: There were significant associations between maternal SO2 exposure and congenital ear malformations risk during the 3 months before conception (OR Q4 vs. Q1 = 1.93, 95% CI = 1.43–2.59) and the 3 months after conception (OR Q4 vs. Q1 = 1.63, 95% CI = 1.22–2.18). Similar results were obtained in the analysis of single-month exposure windows, except for the third month before conception and the third month after conception. Moreover, these findings were broadly consistent across subgroups and robust in sensitivity analyses. There were non-linear dose-response associations between SO2 exposure and congenital ear malformations based on restricted cubic spline model analysis.

Conclusion: Maternal SO2 exposure is associated with increased congenital ear malformations risk in offspring.

A homozygous missense variant in laminin subunit beta 1 as candidate causal mutation of hemifacial microsomia in Romagnola cattle

Hemifacial microsomia (HFM) was diagnosed in a 9‐day‐old Romagnola calf. The condition was characterized by microtia of the left ear, anotia of the right ear, asymmetry of the face, and deafness. Magnetic resonance imaging revealed agenesis of the right pinna and both tympanic bullae, asymmetry of the temporal bones and temporomandibular joints, and right pontine meningocele. Brainstem auditory evoked responses confirmed the impaired auditory capacity. At gross post mortem examination, there was agenesis and hypoplasia of the right and the left external ear, respectively. No histological abnormalities were detected in the inner ears. A trio whole‐genome sequencing approach was carried out and identified a private homozygous missense variant in LAMB1 affecting a conserved residue (p.Arg668Cys). Genotyping of 221 Romagnola bulls revealed a carrier prevalence <2%. This represents a report of a LAMB1‐related autosomal recessive inherited disorder in domestic animals and adds LAMB1 to the candidate genes for HFM.

Craniofacial microsomia: Reflections on diagnosis and severity assessment based on a series of cases

This study aims to discuss diagnostic criteria and severity assessment for craniofacial microsomia (CFM). A series of 61 patients with diverse CFM phenotypes had their clinical data collected by experienced dysmorphologists using a single protocol. Genetic abnormalities were searched through karyotype and chromosomal microarray analysis. Sex ratio, prenatal risk factors, and recurrence rate corroborated the literature. Despite the wide variability of clinical findings, ear disruption was universal. Eight patients were assigned as syndromic, four of whom had demonstrable genetic alterations. The majority of patients (67.2%) fulfilled four known diagnostic criteria, while 9.8% fulfilled one of them. Data strengthened disruptions of the ear and deafness as a semiotically valuable sign in CFM. Facial impairment should consider asymmetry as a mild expression of microsomia. Spinal and cardiac anomalies, microcephaly, and developmental delay were prevalent among extra craniofacial features and should be screened before planning treatment and follow up. The severity index was able to recognize the less and the most affected patients. However, it was not useful to support therapeutic decisions and prognosis in the clinical scenario due to syndromic and non-syndromic phenotypes overlapping. These issues make contemporary the debate on diagnostic methods and disease severity assessment for CFM. They also impact care and etiopathogenetic studies.

Ten-year trends in the incidence of microtia: a nationwide population-based study from Taiwan

PURPOSE

Few studies have explored population-based incidence rates of microtia using nationwide data. The aim of this study was to analyze the 10-year secular trends in the incidence of microtia and/or anotia in Taiwan from 2008 to 2017 using nationwide population-based data.

METHODS

Patient data were retrieved from Taiwan's National Health Insurance Dataset, after identifying 1152 children aged ≤ 1 year with a first-time diagnosis of microtia or anotia between January 2008 and December 2017. The annual microtia-anotia incidence rate was the sum of new microtia-anotia cases in a year divided by total infant population in the year. Furthermore, we used the annual percent change (APC) to study the secular trend in microtia-anotia incidence rate.

RESULTS

The annual incidence rate of microtia-anotia averaged across the 10-year period was 57.7 per 100,000 infants (standard deviation = 8.6). The annual incidence rates of microtia and anotia were 53.3 and 4.4 per 100,000 infants, respectively, during this period. Furthermore, female infants had a higher incidence than males (63.3 vs. 52.4 per 100,000). The incidence of microtia-anotia gradually decreased between 2008 and 2017 with an APC of - 5.64% (95% CI - 9.31 ~ - 1.18%, p = 0.004). Since 2011, females had a significantly higher annual incidence rate of microtia-anotia than males.

CONCLUSIONS

The incidence of microtia-anotia was 57.7 per 100,000 infants in Taiwan, which declined during the study period 2008-2017. The female-to-male incidence ratio was 1.21:1.

Heterogeneity of Accompanying Phenotypes and Genomic Variants Involved in Microtia

OBJECTIVES

The symptoms associated with microtia are ever-changing and not to stick to 1 pattern. The symptoms associated with microtia are constantly changing and are not set in stone. The aim of this article was to describe the various phenotypes from multiple systems found in microtitis patients included in the DatabasE of genomiC varIation and Phenotype in Humans using Ensembl Resources database, and to analyze possible pathogenic mutations.

METHODS

DatabasE of genomiC varIation and Phenotype in Humans using Ensembl Resources is an interactive web-based database, which incorporates a suite of tools designed to aid the interpretation of genomic variants. The term "microtia" was used as the search term, and the data extracted from the DatabasE of genomiC varIation and Phenotype in Humans using Ensembl Resources for this study was updated until October 2020. Pearson chi-squared test was used to test associations between types of genomic variants and the pathogenicity of variants.

RESULTS

Of the 386 cases enrolled in the study, 99% (n = 382) had 1 or more associated abnormalities. The most frequently detected abnormalities were those of the face and neck (n = 362 [93.8% of all cases]); musculoskeletal system (n = 337 [87.3%]); and nervous system (n = 334 [86.5%]), followed by abnormalities of limbs (n = 252 [65.3%]); the eye (n = 212 [54.9%]); and the integument (n = 200 [51.8%]). Besides, a total of 479 genomic variants were determined, including sequence variants and copy number variants (loss and gain). The pathogenicity of loss-type variants was significantly higher among other types (P < 0.001). Twelve sharing variants had more than 5 repeats, and the repeated fragments were concentrated on chromosome 3, 7, 9, 10, 11, 15, 17, 18, and 22.

CONCLUSIONS

Identification of the relation between phenotypes and genotypes will facilitate the uncovering of the mechanism of microtia and the study of potential therapeutic targets.

Whole-exome sequencing analysis in 10 families of sporadic microtia with thoracic deformities

Background

Microtia is a congenital malformation of the external ear and may occur as an isolated deformity or as part of a syndrome. Our previous study found a high correlation between microtia and thoracic deformities, thus, we propose that external ear and thorax development may be regulated by certain genes in common.

Methods

We performed exome sequencing on 10 families of sporadic microtia with thoracic abnormalities. We identified mutated genes under different models of inheritance, and checked them through Mouse Genome Informatics and association analysis.

Results

We identified 45 rare mutations, including 9 de novo mutations, 20 heterozygous mutations, 3 homozygous mutations, and 13 hemizygous mutations, of which 2 are likely to be causative. They are de novo missense variant in PHF5A and compound heterozygous mutations in CYP26B1, of which CYP26B1 mutation is highly likely pathogenic.

Conclusion

The results indicate that certain genes may affect both external ear and thorax development, and demonstrate the benefits of whole‐exome sequencing in identifying candidate genes of microtia. This study provides a new way for genetic exploration in microtia.

[Obstructive sleep apnea in microtia children with maxillofacial dysostosis]

Children with microtia are often associated with maxillofacial dysostosis, such as Treacher Collins syndrome, Goldenhar syndrome, and Nager syndrome, and they are prone to suffer from obstructive sleep apnea（OSA）. Obstruction widely occurred in the upper airway is the main mechanism of OSA in these children, and dysplasia of the pharynx and neurodevelopmental abnormalities may also participate. Early diagnosis requires symptom screening and polysomnography. Imaging techniques and endoscopy can be adopted to fully assess the upper airway status to guide further treatment. According to the child's condition and the main obstruction site, treatment methods include maxillofacial deformity correction, continuous positive pressure ventilation and tracheotomy. OSA in microtia children with maxillofacial dysostosis needs to be identified and treated in time to reduce the adverse effects on the growth and development of children.

Bone-conduction hearing aid is effective in congenital oval window atresia

BACKGROUND

Implantable bone-conduction hearing aids (BCHA) are effective in patients with congenital ear malformations.However, there is no large sample study to verify the efficacy of Bonebridge in patients with congenital oval window atresia.

OBJECTIVES

To investigate efficiency of implantable bone-conduction hearing aids in Mandarin-speaking patients with congenital oval window atresia.

MATERIAL AND METHODS

We retrospectively analyzed 15 patients, who were confirmed with either unilateral or bilateral congenital oval window atresia by temporal bone CT. All patients were implanted with a bone-conduction hearing device between July 2016 and July 2019 at Beijing Tongren Hospital, Capital Medical University. Pure tone audiometry (PTA), air-bone gap (ABG), speech discrimination scores (SDSs), and hearing thresholds were performed.

RESULTS

Postoperative complications including facial paralysis were particularly rare. Unaided mean sound field threshold was 62.2 ± 10.5 dBHL and that with implantable bone-conduction hearing aids was 39.1 ± 13.2 dBHL (p < 0.01). The mean speech discrimination scores improved greatly (p < 0.01), specifically with regard to sentence and disyllabic words.

CONCLUSIONS

Patients with congenital oval window atresia often show moderate to severe conductive hearing loss. Implantable bone-conduction hearing aids are considerably safe and stable for hearing rehabilitation. It is a novel treatment modality for Mandarin-speaking patients with congenital oval window atresia.

Bioinformatics analysis of candidate genes involved in ethanol-induced microtia pathogenesis based on a human genome database: GeneCards

OBJECTIVE

Ethanol used by women during pregnancy increases the risk for microtia in the foetus. Traditionally, laboratory experiments and Mouse Genome Informatics (MGI) have been used to explore microtia pathogenesis. The aim of this study was to screen and verify hub genes involved in ethanol-induced microtia and to explore the potential molecular mechanisms.

METHODS

Overlapping genes related to ethanol and microtia were acquired from the GeneCards database and filtered by confidence score. These genes were further analysed via bioinformatics. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis results were visualized with the clusterProfiler R package. A protein-protein interaction (PPI) network was constructed based on data from the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database.

RESULTS

Overall, 41 genes related to both ethanol and microtia were identified. The genes most relevant to ethanol-induced microtia pathogenesis included FGFR-2, FGFR-3, FGF-8, TP53, IGF1, SHH, CTNNB1, and PAX6, among others. Most genes were strongly enriched for tissue and organ development in GO analysis. Additionally, many genes were enriched in the Ras, FoxO, MAPK, and PI3K-Akt signalling pathways in KEGG analysis.

CONCLUSIONS

Bioinformatics analysis was conducted on genes currently known to be related to ethanol-induced microtia pathogenesis. We propose that mechanisms involving FGF-family genes, TP53, IGF1 and SHH contribute significantly to ethanol-induced microtia and the accompanying malformation of other structures.

Acquisition limitations of bone conduction hearing devices in children with unilateral microtia and atresia

OBJECTIVE

To characterize the use of bone conduction hearing devices (BCHD) for hearing management in children with unilateral congenital aural atresia (CAA) at a tertiary pediatric center's microtia clinic while assessing challenges in acquisition. BCHD generally provides better audiologic outcomes than atresiaplasty in pediatric CAA. BCHD is formally recommended for only bilateral CAA, although literature has begun to show benefit in unilateral CAA.

METHODS

A retrospective case series of patients born between 2014 and 2018 with unilateral microtia at an urban tertiary care children's hospital collected information on demographics, CAA laterality, hearing loss (HL) severity, management, and acquisition. Statistical analysis aided characterization of BCHD use.

RESULTS

131 patients (65% males) were included with a mean age of 3.5 years. 108 (82%) patients with unilateral microtia were used for further analysis, and right sided microtia was most common (67.6%). Of patients with auditory brain response (ABR) testing available, 70% demonstrated conductive HL, 16% mixed HL, 1% sensorineural HL, 6% no HL secondary to grade 1 microtia, and 7% were pending evaluation. Overall, 46 (42.6%) patients with unilateral microtia obtained a BCHD. 68.7% of those offered a BCHD after ABR opted for acquisition. The average length of time from offer to fit was about 6 months.

CONCLUSION

Even with thorough consultation and follow up, less than half of the patients with unilateral CAA received a BCHD. Missed initial ABR appointments that lead to BCHD recommendation seem to be the greatest limiting factor, while demographics did not play a confounding role. Family education and future research on obstacles preventing BCHD use in unilateral CAA will help standardize management and improve hearing within this critical auditory period.