Microtia: epidemiology and genetics

High-resolution computed tomography evaluation of congenital aural atresia - how useful is this?

OBJECTIVE

To depict various temporal bone abnormalities on high-resolution computed tomography in congenital aural atresia patients, and correlate these findings with auditory function test results and microtia subgroup.

METHODS

Forty patients (56 ears) with congenital malformation of the auricle and/or external auditory canal were evaluated. Auricles were graded according to Marx's classification, divided into subgroups of minor (grades I and II) and major (III and IV) microtia. Other associated anomalies of the external auditory canal, tympanic cavity, ossicular status, oval and round windows, facial nerve, and inner ear were evaluated.

RESULTS

Minor and major microtia were observed in 53.6 and 46.4 per cent of ears respectively. Mean hearing levels were 62.47 and 62.37 dB respectively (p = 0.98). The malleus was the most commonly dysplastic ossicle (73.3 vs 80.8 per cent of ears respectively, p = 0.53). Facial nerve (mastoid segment) abnormalities were associated (p = 0.04) with microtia subgroup (80 vs 100 per cent in minor vs major subgroups).

CONCLUSION

Microtia grade was not significantly associated with mean hearing levels or other ear malformations, except for external auditory canal and facial nerve (mastoid segment) anomalies. High-resolution computed tomography is essential in congenital aural atresia, before management strategy is decided.

Exploring the Experiences of Adults With Microtia: A Qualitative Study

OBJECTIVE

Microtia is a medically complex condition, with the option of surgery to address hearing and reconstruct the ear. The current study explored adults' experiences of microtia, with a particular focus on the psychosocial impact and experiences of ear reconstruction. The ultimate aim was to identify areas for support and future research that could improve patient care.

DESIGN

Fifteen adults (12 females) aged between 20 and 62 years took part in semi-structured interviews. Interviews were audio-recorded, transcribed verbatim, and analyzed using inductive thematic analysis.

RESULTS

Three main themes were identified in the data: microtia as an invisible difference, surgery as a welcome opportunity, and living well with microtia. Participants had incorporated microtia into their self-concept and did not report a lasting negative impact on their lives. However, some psychosocial challenges were reported, including anxiety about showing their ears (even after reconstruction), disclosing their diagnosis to romantic partners, surgical decision-making, and feeling unsupported in the work environment.

CONCLUSION

Individuals with microtia may benefit from psychosocial interventions to increase confidence, access to support for treatment decision-making, and guidance around disclosing microtia to employers.

An analytical study of neocartilage from microtia and otoplasty surgical remnants: A possible application for BMP7 in microtia development and regeneration

To investigate auricular reconstruction by tissue engineering means, this study compared cartilage regenerated from human chondrocytes obtained from either microtia or normal (conchal) tissues discarded from otoplasties. Isolated cells were expanded in vitro, seeded onto nanopolyglycolic acid (nanoPGA) sheets with or without addition of bone morphogenetic protein-7 (BMP7), and implanted in nude mice for 10 weeks. On specimen harvest, cartilage development was assessed by gross morphology, histology, and RT-qPCR and microarray analyses. Neocartilages from normal and microtia surgical tissues were found equivalent in their dimensions, qualitative degree of proteoglycan and elastic fiber staining, and quantitative gene expression levels of types II and III collagen, elastin, and SOX5. Microarray analysis, applied for the first time for normal and microtia neocartilage comparison, yielded no genes that were statistically significantly different in expression between these two sample groups. These results support use of microtia tissue as a cell source for normal auricular reconstruction. Comparison of normal and microtia cells, each seeded on nanoPGA and supplemented with BMP7 in a slow-release hydrogel, showed statistically significant differences in certain genes identified by microarray analysis. Such differences were also noted in several analyses comparing counterpart seeded cells without BMP7. Summary data suggest a possible application for BMP7 in microtia cartilage regeneration and encourage further studies to elucidate whether such genotypic differences translate to phenotypic characteristics of the human microtic ear. The present work advances understanding relevant to the potential clinical use of microtia surgical remnants as a suitable cell source for tissue engineering of the pinna.

Duplications involving the long range HMX1 enhancer are associated with human isolated bilateral concha-type microtia

Background

Microtia is a congenital anomaly of ear that ranges in severity from mild structural abnormalities to complete absence of the outer ears. Concha-type microtia is considered to be a mild form. The H6 family homeobox 1 transcription factor gene (HMX1) plays an important role in craniofacial structures development. Copy number variations (CNVs) of a downstream evolutionarily conserved enhancer region (ECR) of Hmx1 associated with ear and eye abnormalities have been reported in different animals, but not yet in human. To date, no genetic defects responsible for isolated human microtia has been reported except for mutations in HOXA2. Here we recruited five Chinese families with isolated bilateral concha-type microtia, and attempt to identify the underlying genetic causes.

Methods

Single Nucleotide polymorphism (SNP) array was performed to map the disease locus and detect CNVs on a genome scale primarily in the largest family (F1). Whole genome sequencing was performed to screen all SNVs and CNVs in the candidate disease locus. Array comparative genomic hybridization (aCGH) was then performed to detect CNVs in the other four families, F2-F5. Quantitative real-time polymerase chain reaction (qPCR) was used to validate and determine the extent of identified CNVs containing HMX1-ECR region. Precise breakpoints in F1 and F2 were identified by gap-PCR and sanger sequencing. Dual-luciferase assays were used to detect the enhancer function. qPCR assays were also used to detect HMX1-ECR CNVs in 61 patients with other types mictrotia.

Results

Linkage and haplotype analysis in F1 mapped the disease locus to a 1.9 Mb interval on 4p16.1 containing HMX1 and its downstream ECR region. Whole genome sequencing detected no potential pathogenic SNVs in coding regions of HMX1 or other genes within the candidate disease locus, but it detected a 94.6 Kb duplication in an intergenic region between HMX1 and CPZ. aCGH and qPCRs also revealed co-segregated duplications in intergenic region downstream of HMX1 in the other four families. The 21.8 Kb minimal overlapping region encompassing the core sequences consensus with mouse ECR of Hmx1. Luciferase assays confirmed the enhancer function in human sequences, and proved that HOXA2 could increase its enhancer activity. No CNVs were detected in HMX1-ECR regions in 61 patients with other type of microtia.

Conclusion

Duplications involving long range HMX1 enhancers are associated with human isolated bilateral concha-type microtia. We add to evidences in human that copy number variations in HMX1-ECR associates with ear malformations, as in other species. This study also provides an additional example of functional conserved non-coding elements (CNEs) in humans.

Long-term Outcomes of Clip Coupler Implantation in Patients with Unilateral Congenital Aural Atresia

OBJECTIVE

To evaluate the long-term safety and efficacy of the Clip coupler attached to the stapes head in patients with unilateral congenital aural atresia (CAA).

METHODS

This single-center retrospective study included 16 Mandarin-speaking patients who had unilateral microtia accompanied by CAA. All patients were divided into two groups: the short-term follow-up group (n = 9) and the long-term follow-up group (n = 7). The floating mass transducer of the Vibrant Soundbridge (VSB) was positioned in the stapes head by the Clip coupler. The safety of the VSB was investigated by comparing preoperative and postoperative bone-conduction (BC) thresholds as well as by complications. The effectiveness was evaluated by functional gain (FG), word recognition score (WRS), speech reception threshold (SRT) and signal-to-noise ratio (SNR).

RESULTS

Pre- and post-operative BC thresholds were no different in all patients. And no complications developed. VSB-aided thresholds in the free-field had improved significantly in both short- and long-term follow-up groups. The improvements of WRS were observed in two groups. The monosyllabic VSB-aided WRS in the long-term follow-up group was significantly higher than that in the short-term follow-up group. When speech was from the impaired ear and noise presented to the side of normal ear (S_VSBN_CL), lower SNRs were found in two groups after VSB implantation. However, there was no statistical difference in aided SNR between the two groups at S_VSBN_CL status.

CONCLUSIONS

Our results show that the FMT connected to the stapes head is a secure and useful device for patients with unilateral CHL/MHL, not only in terms of improved hearing thresholds, but also improved speech intelligibility in quiet and noisy environments.

Renal anomalies and microtia: Determining the clinical utility of screening affected children

OBJECTIVES

Microtia is a congenital ear anomaly that hinders quality of life. Microtia patients, both syndromic and in isolation, may be at-risk for significant renal anomalies that can go undetected at the time of birth. The goal of this study was to characterize the prevalence of renal anomalies among microtia patients at our institution in order to guide optimal patient management. Current guidelines suggest performing a renal ultrasound when there is presence of preauricular pits and ear anomalies in association with dysmorphic features, but not in cases of isolated microtia and atresia.

DESIGN

A retrospective review of 237 children with microtia was conducted from 2001 through 2018 at our tertiary-care pediatric institution, of which 98 also had a documented renal ultrasound. Patients were identified as syndromic or non-syndromic. Data endpoints included renal ultrasounds performed, structural anomalies found, and follow-up.

RESULTS

Among the 237 patients, 98 had received renal ultrasounds. 12% of the total cohort was found to be syndromic, the most common being Goldenhar. Structural anomalies were detected in 24% of the 98 patients that underwent ultrasound and included disorders such as pelviectasis, renal ectopia, duplicated collecting systems, and renal agenesis. A third of patients with anomalies required follow-up with nephrology for chronic kidney disease or renal failure. Of note, 21% of non-syndromic patients and 43% of syndromic patients screened had an abnormality on ultrasonography.

CONCLUSIONS

Children with microtia are at a significant risk of structural renal abnormalities, even when isolated outside of a genetic syndrome. We recommend the strong consideration of performing a screening renal ultrasound in all patients with microtia. Prospective data would be helpful in developing future clinical guidelines regarding the utility of screening ultrasonography.

Duplication in ECR Near HMX1 and a SNP in GATA6 Genes Regulate Microtia in Awassi Sheep

Microtia and anotia are hereditary traits characterized by an underdevelopment or complete absence of the outer ear. These congenital malformations observed in many species can exist as part of various syndromes or as an isolated trait as seen in the fat-tailed Awassi sheep breed. Our study aims to identify the genetic mutations causing microtia in Awassi sheep by DNA sequencing. DNA was extracted from blood samples randomly collected from 84 Awassi sheep (16 earless, 41 short ear and 27 normal ear) across different farms. GATA6 exons 1, 2, 4, 6 and 7, CLRN1 intron 3, DCC intron 2, ECR near HMX1 and the intergenic region between GATA6 and MIB1 genes were screened, amplified and sequenced. Allele and genotype frequencies were calculated by direct counting. Association was performed using chi-squared test for goodness-of-fit. Results showed mutations in only two genes significantly associated with microtia in Awassi: duplication in part of ECR near HMX1 (6:114293121-6:114293196) and a SNP at GATA6 exon 7 (23:34498242). Association results revealed that the ECR locus accounts for the microtia phenotype, while GATA6 exon 7 acts as a modifier gene. Genetic screening for these loci can be used to improve selection against microtia in Awassi sheep.

Sound-localisation performance in patients with congenital unilateral microtia and atresia fitted with an active middle ear implant

OBJECTIVE

This study assessed the safety and sound-localisation ability of the Vibrant Soundbridge (VSB) (Med-EL, Innsbruck, Austria) in patients with unilateral microtia and atresia (MA).

METHODS

This was a single-centre retrospective research study. Twelve subjects with unilateral conductive hearing loss (UCHL) caused by ipsilateral MA were recruited, each of whom underwent VSB implantation and auricular reconstruction. The bone-conduction (BC) threshold was measured postoperatively, and the accuracy of sound localisation was evaluated at least 6 months after surgery. Horizontal sound-localisation performance was investigated with the VSB activated and inactivated, at varying sound stimuli levels (65, 70 and 75 dB SPL). Localisation benefit was analysed via the mean absolute error (MAE).

RESULTS

There was no statistical difference in mean BC threshold of impaired ears measured preoperatively and postoperatively. When compared with VSB-inactivated condition, the MAE increased significantly in unilateral MA patients in the VSB-activated condition. Besides, sound-localisation performance worsened remarkably when sound was presented at 70 dB SPL and 75 dB SPL. Regarding the side of signal location, the average MAE with the VSB device was much higher than that without the VSB when sound was from the normal-hearing ear. However, no significant difference was observed when sound was located from the impaired ear.

CONCLUSION

This study demonstrates that in patients with unilateral MA, the VSB device does not affect inner-ear function. Sound-localisation ability is not improved, but deteriorated at follow-up. Our results suggest that the VSB-aided localisation abilities may be related to the thresholds between the ears, plasticity of auditory system and duration of use of VSB.

Biocompatible implant mimicking cartilage: A new horizon for reconstructive facial field

Cartilage is avascular with limited to no regenerative capacity, so its loss could be a challenge for reconstructive surgery. Current treatment options for damaged cartilage are also limited. In this aspect there is a tremendous need to develop an ideal cartilage-mimicking biomaterial that could repair maxillofacial defects. Considering this fact in this study we have prepared twelve silicone-based materials (using Silicone 40, 60, and 80) reinforced with hydroxyapatite, tri-calcium phosphate, and titanium dioxide which itself has proven their efficacy in several studies and able to complement the shortcomings of using silicones. Among the mechanical properties (Young's modulus, tensile strength, percent elongation, and hardness), hardness of Silicone-40 showed similarities with goat ear (P > .05). Silicone peaks have been detected in FTIR. Both AFM morphology and SEM images of the samples confirmed more roughed surfaces. All the materials were nonhemolytic in hemocompatibility tests, but among the twelve materials S2, S3, S5, and S6 showed the least hemolysis. For all tested bacterial strains, adherence was lower on each material than that grown on the plain industrial silicone material which was used as a positive control. S2, S3, S5, and S6 samples were selected as the best based on mechanical characterizations, surface characterizations, in vitro hemocompatibility tests and bacterial adherence activity. So, outcomes of this present study would be promising when developing ideal cartilage-mimicking biocomposites and their emerging applications to treat maxillofacial defects due to cartilage damage.

Ear malformations: what do radiologists need to know?

Ear malformations represent 50% of ear, nose and throat malformations. Ear malformations cause conductive hearing loss (CHL) and/or sensorineural hearing loss (SNHL) with a significant childhood disability worldwide. Early accurate diagnosis and treatment are mandatory to enhance language and speech development. Understanding the embryology of the ear explains the outcome of ototoxic prenatal insult according to the affected gestational age and the incidence of association among inner, middle, and external ear malformations. Computed tomography (CT) and magnetic resonance imaging (MRI) examinations of the temporal bone are used in the evaluation of ear malformations. In this review article, the spectrum of ear malformations is discussed in detail with hints on the ear embryology, the ear radiological anatomy, and radiological determinant factors of operative reconstruction of ear anomalies.

Characteristics of 43 multiple auricular deformity case families and auricle morphology in 463 microtia patients in South China

Background

Earlier studies have suggested that microtia is a genetic disease with a worldwide incidence of microtia is between 0.83/10,000 and 17.40/10,000. For microtia, auricle morphology is the most crucial characteristic. However, no studies have been performed to characterize the genetic similarity of microtia and auricle morphology similarity. For the sporadic patients, the relationship between the gestational age of parents and the incidence of microtia is unclear. To obtain the characteristics of auricular deformity multiple case family (AD-MCF) and clarify the relationship between genetic similarity and auricle morphology similarity in AD-MCF.

Methods

This study included 463 AD patients who were diagnosed by Sun Yat-sen Memorial Hospital, Sun Yat-sen University, from 2013 to 2019. Among these patients, 116 are from 43 MCF and the other 347 patients are sporadic. For the patients from families, the disease status of the four generations of immediate family members and the family tree map were collected to analyze the similarity of auricle shape in family members. A score evaluated the similarity of auricle shape according to the structure of the residual ear and the similarity in the morphology of each auricle. Moreover, the population distribution of AD and the gestational age of patients were further analyzed.

Results

From 2013 to 2019, a total of 463 patients were diagnosed as microtia in our hospital. There were 427 patients with unilateral disease and 36 patients with bilateral disease. Among them, 116 patients were from 34 families and 9 de novo families. The total scores of patients in different genetic difference levels were compared and were found significantly different (P<0.001). Moreover, 58.14% of families were consistent with the law of chromosomal recessive genetic diseases. Importantly, we found that the gestational age of father in microtia de novo families is 30.94±0.75, and mother in de novo is 28.39±0.73 that is significantly higher than the gestational ages of parents from microtia families with P value =0.0001.

Conclusions

The auricle similarity between family members is positively related to the genetic distance between family members. The microtia patients are potentially associated with the gestational ages of parents.

3D printing for tissue engineering in otolaryngology

Airway and other head and neck disorders affect hundreds of thousands of patients each year and most require surgical intervention. Among these, congenital deformity that affects newborns is particularly serious and can be life-threatening. In these cases, reconstructive surgery is resolutive but bears significant limitations, including the donor site morbidity and limited available tissue. In this context, tissue engineering represents a promising alternative approach for the surgical treatment of otolaryngologic disorders. In particular, 3D printing coupled with advanced imaging technologies offers the unique opportunity to reproduce the complex anatomy of native ear, nose, and throat, with its import in terms of functionality as well as aesthetics and the associated patient well-being. In this review, we provide a general overview of the main ear, nose and throat disorders and focus on the most recent scientific literature on 3D printing and bioprinting for their treatment.

Review of Preferential Suspicious Genes in Microtia Patients Through Various Approaches

Recently, an increasing trend of the birth prevalence of anotia/microtia is observed in China, contributed by changes of social environment and lifestyle. There seems to be no major breakthroughs in exact pathogenesis of microtia, though the research results related to molecular genetics unceasingly appear. In this review, the authors focus on the results of various research methods which the authors regard as the preferential suspicious gene pool to facilitate the exploration of the pathogenic genes of microtia, knowing that the mechanism of microtia is very complicated. The advantages and limitations of these various approaches will also be systematically delineated. The authors believe that this review will give a deep insight in the genetic research of microtia and help plastic surgeons manage congenital microtia more effectively.

Genome-wide association study shows that microtia in Altay sheep is caused by a 76 bp duplication of HMX1

Microtia is a congenital malformation of the external ear that can be observed in many species including sheep. However, the genetic basis of microtia still remains unclear. Here, a GWAS was conducted to investigate the genetic basis underlying microtia. A total of 55 samples from 26 microtia and 29 normal animals were genotyped with Illumina OvineHD BeadChip. The strongest significant SNP was identified on OAR6, approximating the evolutionarily conserved region of the HMX1 gene, which is related to congenital malformations of the external ear in other species such as cattle and rats. Sequencing an evolutionarily conserved region surrounding HMX1 revealed a duplication of 76 bp, which is concordant with microtia, suggesting a dominant inheritance mode. Identification of this causal mutation in the HMX1 gene indicates the role of this particular gene in the development of the external ear and provides a genetic marker for selection against microtia.

Risk factors associated with congenital defects that alter hearing or vision in children born in the city of Bogotá between 2002 and 2016

INTRODUCTION

Congenital defects affecting the auditory and visual capacity of newborns represent a public health problem as they result in substantial disability, directly impacting the quality of life of newborns and their families.

OBJECTIVE

To evaluate risk factors associated with congenital defects that alter hearing or vision in newborns in the city of Bogotá between 2002 and 2016.

METHOD

Data from the Bogotá Birth Defects Surveillance and Follow-up Program was used, which consolidated data regarding 167 ECLAMC study (Estudio Colaborativo Latino Americano de Malformaciones Congénitas, in spanish) variables in a case-control design to identify risk factors for birth defects after parents provided signed informed consent. Cases were defined as any newborn (alive or stillborn) with a weight greater than 500 g with any visual or hearing abnormality. Controls were defined as newborn in the same hospital and month with no birth defects. Groups were formed according to the case presentation as follows: isolated eye anomaly, isolated ear anomaly, polymalformative, syndromic, and teratogenic.

RESULTS

In total, 402,657 births were reviewed, of which 968 cases had some congenital defects that alter hearing or vision. An association was found between the presence of defects and prematurity, as well as between syndromic cases and increasing maternal age. When comparing cases and controls with the risk of having a birth defect, multiparity had an odds ratio (OR) of 1.47 (95% CI: 1.27-1.71), acute respiratory infection had an OR of 2.41 (95% CI: 1.04-5.58), low maternal education level had an OR of 1.34 (95% CI:1.10-1.62), low paternal education had an OR of 1.42, (95% CI:1.17-1.73), manual labor in the maternal occupation had an OR of 1.31 (95% CI:1.03-1.67), and a history of congenital anomalies in the family had an OR of 1.55 (95% CI:1.19-2.00).

CONCLUSION

This research allowed the identification of epidemiological data and significant risk factors for congenital defects that alter hearing or vision in the population of Bogotá.

Tissue Engineering Auricular Cartilage Using Late Passage Human Auricular Chondrocytes

PURPOSE

The significant shortcomings associated with current autologous reconstructive options for auricular deformities have inspired great interest in a tissue engineering solution. A major obstacle in the engineering of human auricular cartilage is the availability of sufficient autologous human chondrocytes. A clinically obtainable amount of auricular cartilage tissue (ie, 1 g) only yields approximately 10 million cells, where 25 times this amount is needed for the fabrication of a full-scale pediatric ear. It is thought that repeated passaging of chondrocytes leads to dedifferentiation and loss of the chondrogenic potential. However, little to no data exist regarding the ideal number of times that human auricular chondrocytes (HAuCs) can be passaged in a manner that maximizes the cellular expansion while minimizing dedifferentiation.

METHODS

Human auricular chondrocytes were isolated from discarded otoplasty specimens. The HAuCs were then expanded, and cells from passages 3, 4, and 5 were encapsulated into discs 8 mm in diameter made from type I collagen hydrogels with a cell density of 25 million cells/mL. The constructs were implanted subcutaneously in the dorsa of nude mice and harvested after 1 and 3 months for analysis.

RESULTS

Constructs containing passages 3, 4, and 5 chondrocytes all maintained their original cylindrical geometry. After 3 months in vivo, the diameters of the P3, P4, and P5 discs were 69 ± 9%, 67 ± 10%, and 73 ± 15% of their initial diameter, respectively. Regardless of the passage number, all constructs developed a glossy white cartilaginous appearance, similar to native auricular cartilage. Histologic analysis demonstrated development of an organized perichondrium composed of collagen, a rich proteoglycan matrix, cellular lacunae, and a dense elastin fibrin network by Safranin-O and Verhoeff stain. Biochemical analysis confirmed similar amounts of proteoglycan and hydroxyproline content in late passage constructs when compared with native auricular cartilage.

CONCLUSIONS

These data indicate that late passage HAuCs (up to passage 5) form elastic cartilage that is histologically, biochemically, and biomechanically similar to native human elastic cartilage and have the potential to be used for auricular cartilage engineering.

Reconstruction of Congenital Microtia and Anotia: Analysis of Practitioner Epidemiology and Postoperative Outcomes

BACKGROUND

Microtia refers to a congenital malformation of the external ear that is associated with a range of functional, psychosocial, aesthetic, and financial burdens. The aim of this study was to analyze the epidemiology and postoperative complication profile of microtia reconstruction.

METHODS

A retrospective review was conducted using data from the 2012-2017 the American College of Surgeons National Quality Improvement Program Pediatric databases. Patients with a diagnosis of microtia or anotia were identified using International Classification of Diseases codes. Demographics and postoperative complications were analyzed using Chi-square and t tests for categorical and continuous variables, respectively. Multivariable regression was performed to control for confounding variables.

RESULTS

A total of 466 cases were analyzed, of which 290 (62.2%) were performed by plastic surgeons and 176 (37.8%) by otolaryngologists (ear, nose, and throat physicians [ENT]). Autologous reconstruction was the predominant approach [76.2% of cases (n = 355)] in this cohort. ENT physicians operated on a significantly younger patient population (mean age 8.4 ± 3.2 years versus 10.0 ± 3.2 years, P< 0.001) and had higher rates of concurrent atresia/middle ear repair [21.0% (n = 37) versus 3.7% (n = 17)] compared with plastic surgeons. The rate of all-cause complications was 5.9% (n = 17) in the plastic surgery cohort and 4.0% (n = 7) in the ENT cohort (P= 0.372). Multivariable regression did not reveal any statistically significant predictors for all-cause complications.

CONCLUSIONS

Reconstruction of the external ear for patients with microtia/anotia is a safe procedure, with low rates of postoperative complications, readmissions, and reoperations. Autologous reconstruction remains the preferred modality for repair of the external ear and simultaneous atresiaplasty/middle ear repair does not increase the risk of complications.

Fetal microtia and FGFR2 polymorphism

Association of the single-nucleotide polymorphism (SNP) of rs3135718 site in fibroblast growth factor receptor 2 (FGFR2) gene with congenital microtia was investigated. A total of 193 patients with congenital microtia (observation group) and 150 normal and healthy fetuses (control group) treated in Maternity and Child Health Care of Zaozhuang from January 2010 to October 2017 were randomly selected. The gene and genotype of the rs3135718 site of FGFR2 gene SNP were detected via quantitative polymerase chain reaction (qPCR). The association between rs3135718 site SNP and congenital microtia was analyzed. No statistically significant difference in the prevalence of congenital microtia was observed in the rs3135718 genotype (AG) between the observation and control group (P>0.05). The GG and G genotypes in rs3135718 were closely related to fetal microtia (P<0.05). Results revealed that the rs3135718-GG mutation was more correlated with the risk of microtia in male (P<0.05), but not correlated with the risk of microtia in female (P>0.05). Moreover, there was a statistically significant difference in the distribution of rs3135718-G allele frequency in male between the two groups (P<0.05). The rs3135718-G gene in FGFR2 has a certain association with the incidence of congenital microtia with high prevalence and risk.

Auricular Reconstructive Surgery Improvement to the Firmin Technique for Placing an Earring

Microtia has an incidence of 1 in 7000 to 8000 births. Ear reconstruction has 2 main aims: reconstructive and aesthetic, and a considerable number of patients ask for an earring at the end of their treatment. Herein, we explain our team's modification to the Firmin technique, perforating the lowest part of the autologous cartilage framework (Parri's modification). The orifice is cartilaginous and the skin covering both sides is easily perforable without contacting the rest of the framework. In conclusion, our modification for placing an earring is simple; it does not increase the surgical time and contributes to approach the perfection of auricular reconstructive surgery.

Identification of sequence variants associated with severe microtia-astresia by targeted sequencing

Background

Microtia-atresia is characterized by abnormalities of the auricle (microtia) and aplasia or hypoplasia of the external auditory canal, often associated with middle ear abnormalities. To date, no causal genetic mutations or genes have been identified in microtia-atresia patients.

Methods

We designed a panel of 131 genes associated with external/middle or inner ear deformity. Targeted genomic capturing combined with next-generation sequencing (NGS) was utilized to screen for mutations in 40 severe microtia-atresia patients. Mutations detected by NGS were filtered and validated. And then mutations were divided into three categories—rare or novel variants, low-frequency variants and common variants—based on their frequency in the public database. The rare or novel mutations were prioritized by pathogenicity analysis. For the low-frequency variants and common variants, we used association studies to explore risk factors of severe microtia-atresia.

Results

Sixty-five rare heterozygous mutations of 42 genes were identified in 27 (67.5%) severe microtia-atresia patients. Association studies to determine genes that were potentially pathogenic found that PLEC, USH2A, FREM2, DCHS1, GLI3, POMT1 and GBA genes were significantly associated with severe microtia-atresia. Of these, DCHS1 was strongly suggested to cause severe microtia-atresia as it was identified by both low-frequency and common variants association studies. A rare mutation (c.481C > T, p.R161C) in DCHS1 identified in one individual may be deleterious and may cause severe microtia-atresia.

Conclusion

We identified several genes that were significantly associated with severe microtia-atresia. The findings provide new insights into genetic background of external ear deformities.

Electronic supplementary material

The online version of this article (10.1186/s12920-019-0475-x) contains supplementary material, which is available to authorized users.

Different suturing techniques in thoracic incision: protocol for a feasibility randomised controlled trial

INTRODUCTION

Based on the principles of the ideal skin closure technique, we previously described a suture technique (wedge-shaped excision and modified buried vertical mattress suture (WE-MBVMS)) that could provide excellent outcomes for the most demanding surfaces. However, adequate clinical comparative evidence supporting improved outcomes is lacking. Thus, the purpose of this protocol is to establish the feasibility of conducting a fully randomised controlled trial (RCT) comparing the clinical effectiveness of WE-MBVMS with a buried intradermal suture (BIS) in closing thoracic incision.

METHODS AND ANALYSIS

This study is a feasibility RCT of WE-MBVMS and BIS in patients undergoing surgery for costal cartilage harvesting. Seventy-eight participants are expected to participate in the study and will be randomised in a ratio of 1:1 to WE-MBVMS or BIS. Trial feasibility will be assessed by the number of participants assessed for eligibility, recruitment rates, reasons for ineligibility or non-participation, time for interventions, withdrawal and retention at all follow-up points (3, 6 and 12 months), follow-up rates and reasons for withdrawing from the trial. In addition, clinical data regarding the cosmetic results of scars will be collected to inform the sample size for a fully powered RCT.

ETHICS AND DISSEMINATION

This study has been approved by The First Affiliated Hospital of Xi'an Jiaotong University Institutional Review Board (XJTU1AF2017LSK-120). The findings will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ChiCTR-INR-17013335; Pre-results.

Impact of unilateral congenital aural atresia on academic Performance: A systematic review

BACKGROUND

Little is known about the academic performance of children with unilateral congenital aural atresia (CAA).

OBJECTIVE

of review: Our objective was to summarize what is known about the academic performance of children with hearing loss by unilateral congenital aural atresia, in order to provide pragmatic recommendations to clinicians who see children with this entity.

TYPE OF REVIEW

Systematic review.

SEARCH STRATEGY

We conducted a systematic search in PubMed Medline, EMBASE, and Cochrane Library combining the terms "atresia" and synonyms with "unilateral hearing loss" and synonyms. Date of the most recent search was 16 May 2018.

EVALUATION METHOD

Two independent authors identified studies, extracted data, and assessed risk of bias. This review was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Observational studies on the academic achievements of patients of any age with unilateral conductive hearing loss of any level due to congenital aural atresia were included. We considered grade retention, special education, individualized education plans, and parental report of school performance as outcome measures for academic achievement.

RESULTS

Two studies reporting on academic performance of patients with unilateral CAA, which both had a significant risk of bias. One study (n = 140) showed a grade retention rate of 3.6% (n = 5) in total. 15.7% (n = 22) needed special education, and 36.4% (n = 51) used an individualized education program. The second study, reporting on 67 patients with unilateral CAA, showed that 29.9% (n = 20) of the patients received school intervention, and 25.4% (n = 17) had learning problems.

CONCLUSION

Current evidence regarding the effect of unilateral congenital aural atresia on academic performance is sparse, inconclusive and has a significant risk of bias. High quality observational studies assessing the effects of aural atresia on academic performance in these patients should be initiated.

Tissue engineering the human auricle by auricular chondrocyte-mesenchymal stem cell co-implantation

Children suffering from microtia have few options for auricular reconstruction. Tissue engineering approaches attempt to replicate the complex anatomy and structure of the ear with autologous cartilage but have been limited by access to clinically accessible cell sources. Here we present a full-scale, patient-based human ear generated by implantation of human auricular chondrocytes and human mesenchymal stem cells in a 1:1 ratio. Additional disc construct surrogates were generated with 1:0, 1:1, and 0:1 combinations of auricular chondrocytes and mesenchymal stem cells. After 3 months in vivo, monocellular auricular chondrocyte discs and 1:1 disc and ear constructs displayed bundled collagen fibers in a perichondrial layer, rich proteoglycan deposition, and elastin fiber network formation similar to native human auricular cartilage, with the protein composition and mechanical stiffness of native tissue. Full ear constructs with a 1:1 cell combination maintained gross ear structure and developed a cartilaginous appearance following implantation. These studies demonstrate the successful engineering of a patient-specific human auricle using exclusively human cell sources without extensive in vitro tissue culture prior to implantation, a critical step towards the clinical application of tissue engineering for auricular reconstruction.

Simultaneous auricular reconstruction combined with bone bridge implantation-optimal surgical techniques in bilateral microtia with severe hearing impairment

BACKGROUND

Congenital bilateral microtia with external ear canal (EAC)/middle ear malformation lead to severe appearance defects, hearing impairment and language barrier. Here we report an optimal integrated surgical technique for BoneBridge implantation and auricular reconstruction, which reduce time span of operation, total cost and patients' suffering as well.

METHOD

Seven patients with bilateral external and middle ear malformation received 2-stage auricular reconstruction (age from 7 to 11 years old). In the 1st stage, 6th, 7th, and part of 8th autologous costal cartilage were used to make main body and C-shaped base part of the framework. In 2nd stage of the operation, dissect and lift the framework, isolate postauricular fascia and periosteum, put the BoneBridge subperiosteally and fixed with titanium screw. The C-shaped cartilage base was further attached to the framework and retroauricular fascial flaps and a full-thickness skin graft obtained from the donor site was used to cover posterior raw surface.

RESULTS

Patients were followed up for about 8 months post operation, all of them satisfied with the outcomes and symmetric shape on both sides about desirable 3D detail without adverse complications. Hearing test indicated the mean improvement of auditory threshold of 34.8 dB HL 3 weeks after BoneBridge implantation, with mean scores of speech recognition test ranging from 26% to 62%.

CONCLUSION

The combined 2-stage surgical techniques of simultaneous auricular reconstruction and BoneBridge implantation is safe and efficient for bilateral microtia with significant advantages in decreasing operation difficulties, shortening treatment span and relieving suffering for patients.

Renal ultrasound abnormalities in children with syndromic and non-syndromic microtia

OBJECTIVE

Renal abnormalities are commonly considered in the work up of pediatric patients with external ear malformations. However, there is little consensus regarding an appropriate renal screening protocol for patients with microtia. We sought to characterize renal abnormalities detected on ultrasonography in pediatric patients with microtia.

METHODS

We conducted a retrospective cohort study of pediatric patients diagnosed with microtia who underwent renal ultrasound from 1991 to 2014 at a single tertiary academic institution. Renal ultrasound reports and medical records were reviewed to assess for renal abnormalities and to determine whether patients required specialist follow-up or interventions. Audiograms and otolaryngology notes were used to determine patterns of hearing loss. The following additional information was recorded from the electronic medical records: patient sex, microtia grade (I-IV), microtia laterality, and known associated syndromes. Characteristics were compared between those who did and did not have renal ultrasound findings using Fisher's exact test. Univariate logistic regression analysis was performed to determine factors associated with renal ultrasound findings.

RESULTS

The majority of patients in this cohort were syndromic (n = 51, 64%) with grade III microtia (n = 46, 58%) and conductive hearing loss (n = 58, 72%). Syndromic children with microtia demonstrated a higher crude rate of renal ultrasound abnormalities (22%) than children with isolated microtia (7%). Of these patients, 69% required specialist follow-up. Univariate logistic regression analysis did not identify predictors that were significantly associated with renal ultrasound findings.

CONCLUSION

Fairly high rates of abnormalities in syndromic and non-syndromic patients may warrant screening renal ultrasound in all patients with microtia, especially given the high percentage of findings requiring renal follow-up. A prospective study to formally evaluate screening efficacy is needed.

Development of a New Patient-reported Outcome Measure for Ear Conditions: The EAR-Q

Background:

Patient-reported outcome measures are widely used to improve health services and patient outcomes. The aim of our study was to describe the development of 2 ear-specific scales designed to measure outcomes important to children and young adults with ear conditions, such as microtia and prominent ears.

Methods:

We used an interpretive description qualitative approach. Semi-structured qualitative and cognitive interviews were performed with participants with any type of ear condition recruited from plastic surgery clinics in Canada, Australia, United States, and United Kingdom. Participants were interviewed to elicit new concepts. Interviews were audio-recorded, transcribed, and coded using the constant comparison approach. Experts in ear reconstruction were invited to provide input via an online Research Electronic Data Capture survey.

Results:

Participants included 25 patients aged 8–21 years with prominent ears (n = 9), microtia (n = 14), or another condition that affected ear appearance (n = 2). Analysis of participant qualitative data, followed by cognitive interviews and expert input, led to the development and refinement of an 18-item ear appearance scale (eg, size, shape, look up close, look in photographs) and a 12-item adverse effects scale (eg, itchy, painful, numb).

Conclusions:

The EAR-Q in currently being field-tested internationally. Once finalized, we anticipate the EAR-Q will be used in clinical practice and research to understand the patient’s perspective of outcomes following ear surgery.

Applications and challenges of using 3D printed implants for the treatment of birth defects

Pediatric implants are a special subclass of a vast number of clinically used medical implants, uniquely designed to address the needs of young patients who are at the onset of their developmental growth stage. Given the vulnerability of the implant receiver, it is crucial that the implants manufactured for small children with birth-associated defects be given careful considerations and great attention to design detail to avoid postoperative complications. In this review, we focus on the most common types of medical implants manufactured for the treatment of birth defects originating from both genetic and environmental causes. Particular emphasis is devoted toward identifying the implant material of choice and manufacturing approaches for the fabrication of pediatric prostheses. Along this line, the emerging role of 3D printing to enable customized implants for infants with congenital disorders is presented, as well as the possible complications associated with prosthetic-related infections that is prevalent in using artificial implants for the treatment of birth malformations.

Early Familial Experiences With Microtia: Psychosocial Implications for Pediatric Providers

This study focuses on early experiences of families with a child with microtia to better inform their ongoing care by pediatric providers. Parents and children (n = 62; mean age of 6.9 ± 3.9 years) with isolated microtia participated in semistructured interviews in Spanish (66.1%) or English (33.9%). Qualitative analysis of responses used open coding to identify themes. Parents reported stressful informing experiences of the diagnosis with multiple negative emotions. Parents and children generally reported not understanding microtia etiology, while some families identified medical, religious, and folk explanations. Parental coping included learning about surgeries, normalization, perspective taking, and support from family, providers, religion, and others with microtia. Family communication centered on surgery and reassurance. Pediatricians of children with microtia need to understand families' formative psychosocial experiences to better promote positive family adjustment through clarifying misinformation, educating families about available treatment options, modeling acceptance, psychosocial screening, and providing resources.

Descriptive Analysis of the Arterial Supply to the Auricle in Patients with Unilateral Microtia

Background:

Microtia is a congenital auricular deformity that occurs in 1:5,000–10,000 births. It can cause severe impairment to the patient’s self-esteem and problems regarding social integration. Multiple measures have been described in attempt to better operative outcomes of these patients. We used computed tomography (CT) angiography to analyze the vascular pattern of the auricular region before surgery.

Methods:

Fourteen patients with unilateral microtia were included. All underwent CT angiogram plus tridimensional reconstruction. Both healthy and microtic auricles were analyzed descriptively in terms of main arterial supply, pattern, diameter of subbranches, and angulation. The sample was divided in 2 age groups for better understanding of the data.

Results:

Blood supply to the auricle was found to depend on 2 main vessels: temporal superficial artery (TSA) and its subbranches (superior, middle, and lower branch) and posterior auricular (PA) artery. In the microtic group, TSA was the dominant artery in 13 of 14 cases (92%). Superior, middle, and inferior branches were present in 4, 3, and 0 cases, respectively. Three of the microtic auricles presented supply from PA artery, from which in 1 case, it represented the only supply to the region.

Conclusions:

There is wide variability in the blood supply of both healthy and microtic auricles; however, we were able to identify some tendencies in our sample. Further research is needed to prove the benefit of a preoperative imaging study in these patients. Still, in our experience, we found it useful as a complement for surgical planning.

Characterization of congenital craniofacial anomalies in a specialized hospital of Risaralda, Colombia. 2010-2014

Introducción. Los defectos craneofaciales congénitos pueden causar un impacto en la vida de los niños y de sus familias cuando comprometen el rostro. Además, pueden estar acompañados de alteración de las funciones cerebrales o de la apariencia facial. No se tienen datos concluyentes sobre la presencia de estos defectos en el Eje Cafetero.Objetivo. Identificar la frecuencia de las malformaciones craneofaciales congénitas en un periodo de cuatro años en una institución privada de la ciudad de Pereira, en Risaralda, Colombia.Materiales y métodos. Estudio trasversal retrospectivo. La información fue recolectada a través del sistema de información de historias clínicas de pacientes que consultaron por primera vez en una institución privada de salud. El análisis estadístico fue realizado mediante el software R y Microsoft Excel versión 2007.Resultados. Entre enero del 2010 y diciembre del 2014 se atendieron 1 807 pacientes con malformaciones craneofaciales congénitas, lo que corresponde al 19.5% del total de las anomalías congénitas. La hendidura labio-palatina fue la más frecuente.Conclusiones. Aunque las malformaciones craneofaciales congénitas se presentan con frecuencia, se sabe muy poco de su etiología. El diagnóstico temprano puede prevenir futuras complicaciones que deterioren la salud o que generen un sobrecosto para el sistema de salud.

Auricular Retentive Prosthetic Conformer Post Brent's Stage III Surgery in Microtia Repair: A Clinical Report

Auricular reconstruction is an interdisciplinary approach where multiple specialties play a vital role in the treatment provided to the patient. This article provides a comprehensive interpretation of the process carried out for the fabrication of a custom-made prosthetic conformer for the management of postoperative contraction of a skin graft after ear reconstruction surgery-Brent stage III. The prosthesis is used as a precautionary measure and is simple, effective, and economical.

Parental preferences for the first consultation for microtia

OBJECTIVES

The aim of our study was to investigate subjective information concerning parental experiences and preferences with regard to the initial information that is provided right after the birth of a child with microtia. The analysis of these data is intended to help professionals improve the way in which such conversations are conducted. As a result, future parents may feel better informed and, hence, better fit to cope with challenges they may encounter having a child with microtia.

METHODS

A self-administered questionnaire was sent to 106 parents and caretakers of children with microtia who visited the annual International Microtia and Atresia Conference in the Netherlands, May 2016.

RESULTS

Eighty-seven questionnaires were returned (response rate 82%). Results revealed that 26% of the participants did not receive any information about the condition in the perinatal period. Participants who did receive information right after birth were informed by pediatricians and otolaryngolosits in most of the cases. Plastic surgeons and maxillofacial surgeons were the less commonly serving specialties in this role. A majority of the participants experienced their informing consultation as either being "terrible", or "bad". Parents desired more information about all domains regarding microtia. Development, clothing and appearance, and psychology were believed to be the least important domains.

CONCLUSIONS

Parents are dissatisfied with several aspects of the initial information that is provided right after the birth of a child with microtia. We believe that there is a need for correct information and patient- and family centered care administered by multiple disciplines.

Content Validity of Patient-Reported Outcome Instruments used with Pediatric Patients with Facial Differences

Objective:

The aim of this systematic review was to identify patient-reported outcome (PRO) instruments used in research with children/youth with conditions associated with facial differences to identify the health concepts measured.

Design:

MEDLINE, EMBASE, CINAHL, and PsycINFO were searched from 2004 to 2016 to identify PRO instruments used in acne vulgaris, birthmarks, burns, ear anomalies, facial asymmetries, and facial paralysis patients. We performed a content analysis whereby the items were coded to identify concepts and categorized as positive or negative content or phrasing.

Results:

A total of 7,835 articles were screened; 6 generic and 11 condition-specific PRO instruments were used in 96 publications. Condition-specific instruments were for acne (four), oral health (two), dermatology (one), facial asymmetries (two), microtia (one), and burns (one). The PRO instruments provided 554 items (295 generic; 259 condition specific) that were sorted into 4 domains, 11 subdomains, and 91 health concepts. The most common domain was psychological (n = 224 items). Of the identified items, 76% had negative content or phrasing (e.g., “Because of the way my face looks I wish I had never been born”). Given the small number of items measuring facial appearance (n = 19) and function (n = 22), the PRO instruments reviewed lacked content validity for patients whose condition impacted facial function and/or appearance.

Conclusions:

Treatments can change facial appearance and function. This review draws attention to a problem with content validity in existing PRO instruments. Our team is now developing a new PRO instrument called FACE-Q Kids to address this problem.

Whole-exome sequencing for monozygotic twins discordant for hemifacial microsomia

Hemifacial microsomia (HFM) is the second most common congenital craniofacial malformation. Although many sporadic and familial cases have been studied to explore the etiology and pathogenesis of HFM, no common understanding has been reached. We aimed to further probe into the etiology of HFM through studying monozygotic twins. Here, we report two cases of pairs of monozygotic twins discordant for HFM, and performed whole-exome sequencing (WES) and bioinformatics analysis to help determine the underlying molecular mechanisms. We identified 93 and 83, and 101 and 104 genes containing rare germline mutations in the twins of the two pairs, respectively. No positive gene candidates were found among the samples, and none of the analyses results revealed a clear intersection with previously reported gene candidates. The pathogenesis of HFM twin pairs does not appear to be related to single nucleotide variants or small insertions/deletions. Thus, HFM may be caused by structure variations, epigenetic alterations, and/or instability of short repeat sequences, which requires further investigation in a larger cohort with sequencing technology for verification.

Clinical and cytogenomic findings in OAV spectrum

The oculoauriculovertebral spectrum (OAVS) is characterized by anomalies involving the development of the first and second pharyngeal arches during the embryonic period. The phenotype is highly heterogeneous, involving ears, eyes, face, neck, and other systems and organs. There is no agreement in the literature for the minimum phenotypic inclusion criteria, but the primary phenotype involves hemifacial microsomia with facial asymmetry and microtia. Most cases are sporadic and the etiology of this syndrome is not well known. Environmental factors, family cases that demonstrate Mendelian inheritance, such as preauricular appendages, microtia, mandibular hypoplasia, and facial asymmetry; chromosomal abnormalities and some candidate genes suggest a multifactorial inheritance model. We evaluated clinical, cytogenomic and molecularly 72 patients with OAVS, and compared our findings with patients from the literature. We found 15 CNVs (copy number variations) considered pathogenic or possibly pathogenic in 13 out of 72 patients. Our results did not indicated a single candidate genomic region, but recurrent chromosomal imbalances were observed in chromosome 4 and 22, in regions containing genes relevant to the OAVS phenotype or related to known OMIM diseases suggesting different pathogenic mechanisms involved in this genetically and phenotypic heterogeneous spectrum.

Low-set ears and associated anomalies in human foetuses

OBJECTIVES

To determine the prevalence of low-set ears (LSE) in a group of human foetuses, to analyse the associated anomalies, and to review the development mechanisms possibly involved.

METHODS

A total of 1759 human foetuses from spontaneous abortion were evaluated. Foetuses were obtained from the Foetuses and Embryos Collection of the Embryology Department of the Faculty of Medicine of the Autonomous University of Nuevo León. The Ethics Committee gave its approval for this study (EH-230-16). The position of the auricles was determined according to the standards recommended by the Elements of Morphology. Two study groups were created: foetuses with LSE and foetuses with normal ears. In both groups, a detailed examination of the external morphology was performed, followed by thoraco-abdominal micro dissection. Statistical analysis was performed.

RESULTS

Two hundred two of the foetuses presented LSE (1148 per 10,000). In this group, 68.8% did not present associated anomalies, while 31.2% had an associated anomaly. The most frequently affected organ was the heart (53.6%), followed by the digestive tract (23.9%), urinary system (16.9%), head and neck (4.2%), and limbs (1.4%). In the group of foetuses with normal ears, only 7.4% of the specimens had associated anomalies, which was a significant difference compared with the LSE group.

CONCLUSIONS

Based on the obtained results, we consider that LSE can be used as a sensitive indicator of major anomalies. It is recommended to include a systematic assessment of the position of the auricles in the initial clinical evaluation of any newborn.

Prevalence of Renal and Cervical Vertebral Anomalies in Patients with Isolated Microtia and/or Aural Atresia

Objective

The objective of this study was to determine whether patients with isolated microtia or aural atresia have an increased prevalence of renal or cervical vertebral anomalies.

Design

The study design was a retrospective medical record review.

Setting

The setting was the following four distinct institutions: an urban tertiary care children's hospital, two urban academic medical centers, and a staff-model health maintenance organization.

Participants

Patients diagnosed with microtia, aural atresia, or oculoauriculovertebral spectrum were identified. Patients with facial asymmetry, craniofacial microsomia, and other craniofacial abnormalities or syndromes were excluded.

Main Outcome Measures

Main outcome measures were the number of patients with isolated microtia or aural atresia who underwent a renal ultrasound or cervical spine X-ray, the results of those studies, and further evaluation or treatment for any abnormalities found.

Statistical Analysis

A binomial analysis using a one-sided 95% confidence level was performed.

Results

A total of 514 patients with isolated microtia and/or aural atresia were identified. Of these patients, 145 (28%) had undergone a renal ultrasound and 81 (16%) had undergone cervical spine X-rays. A total of 3 patients (2%) had minimal renal pelviectasis, all of which had resolved on repeat ultrasound and required no treatment. There were no structural renal abnormalities identified, and there were no cervical spine abnormalities identified.

Conclusions

The data suggest that there is no increased prevalence of structural renal or cervical vertebral anomalies in patients with isolated microtia and/or aural atresia. Therefore, these patients do not require routine screening renal ultrasound or cervical spine X-rays.

Evaluation of tracheobronchial branching abnormalities in patients with microtia using chest computed tomography

BACKGROUND

The objective of this study was to identify the characteristics and incidence of Tracheobronchial branching abnormalities in patients with microtia and to evaluate the risk of anesthesia.

METHODS

A total of 204 consecutive microtia patients and 465 nose cosmetic patients without microtia received a preoperative chest computed tomography. A retrospective study was performed with the clinical and imaging data from July 2016 to April 2017.

RESULTS

With the chest computed tomography images, a total of 7 cases were documented with Tracheobronchial branching abnormalities, including 6 cases among the microtia patients and 1 case among the cosmetic patients without microtia. The incidence of Tracheobronchial branching abnormalities was higher in microtia patients than the cosmetic patients without microtia (2.94% versus 0.22%, P < 0.01).

CONCLUSIONS

The incidence of Tracheobronchial branching abnormalities was high in patients with microtia. Preoperative diagnosis of tracheal bronchus can help anesthesiologists avoid complications. Microtia with Tracheobronchial branching abnormalities may involve a new syndrome previously undiscovered or just another extension with the very wide spectrum of microtia.

Evaluation of 4 Outcomes Measures in Microtia Treatment: Exposures, Infections, Aesthetics, and Psychosocial Ramifications

Background:

In craniofacial microsomia, microtia and canal atresia pose formidable reconstructive challenges. We review our institutional experience in treating microtia and atresia to identify variables associated with 4 outcomes measures: complications, surgical revisions, aesthetic outcomes, and psychosocial function.

Methods:

Craniofacial microsomia patients treated at the University of California Los Angeles Craniofacial Clinic between 2008 and 2014 greater than 13 years of age (n = 68) were reviewed for microtia and atresia treatment and outcomes.

Results:

In total, 91.2% of patients diagnosed with craniofacial microsomia presented with microtia, affecting 75 ears. Both a male and right-sided predominance were observed. Fifty-six patients (90.3%) underwent autologous external ear reconstruction at an average age of 8.5 years. Age, type of incision, and size of cartilage framework did not predict total number of surgeries or complications. Severity of ear anomalies correlated with increased number of surgeries (P < 0.001) and decreased aesthetic outcomes (P < 0.001) but not complications. In total, 87.1% of patients with microtia had documented hearing loss, of which the majority were conductive and 18.5% were mixed sensorineural and conductive. Hearing deficits were addressed in 70.4% of patients with external hearing aids, bone anchored hearing aids, or canaloplasty. Of all variables, improvement of psychosocial function was correlated only to hearing loss treatment of any type (P = 0.01).

Conclusions:

On evaluation of surgical and patient characteristics, severity of microtia predicted the total number of surgical revisions performed and aesthetic ratings. In addition, we found that the only factor that correlated with improved patient and parent-reported psychosocial outcomes was treatment of hearing loss.

Target sequencing of 307 deafness genes identifies candidate genes implicated in microtia

Microtia is a congenital malformation of the external ear caused by genetic and/or environmental factors. However, no causal genetic mutations have been identified in isolated microtia patients. In this study, we utilized targeted genomic capturing combined with next-generation sequencing to screen for mutations in 307 deafness genes in 32 microtia patients. Forty-two rare heterozygous mutations in 25 genes, including 22 novel mutations in 24 isolated unilateral microtia cases were identified. Pathway analysis found five pathways especially focal adhesion pathway and ECM-receptor interaction pathway were significantly associated with microtia. The low-frequency variants association study was used and highlighted several strong candidate genes MUC4, MUC6, COL4A4, MYO7A, AKAP12, COL11A1, DSPP, ESPN, GPR98, PCDH15, BSN, CACNA1D, TPRN, and USH1C for microtia (P = 2.51 × 10^-4). Among these genes, COL4A4 and COL11A1 may lead to microtia through focal adhesion pathway and ECM-receptor interaction pathway which are connected to the downstream Wnt signaling pathway. The present results indicate that certain genes may affect both external/middle and inner ear development, and demonstrate the benefits of using a capture array in microtia patients.