Optimal timing for plastic surgical procedures for common congenital anomalies: A review.

Apart from listening to the cry of a healthy newborn, it is the declaration by the attending paediatrician in the labour room that the child is normal which brings utmost joy to parents. The global incidence of children born with congenital anomalies has been reported to be 3%-6% with more than 90% of these occurring in low- and middle-income group countries. The exact percentages/total numbers of children requiring surgical treatment cannot be estimated for several reasons. These children are operated under several surgical disciplines, viz, paediatric-, plastic reconstructive, neuro-, cardiothoracic-, orthopaedic surgery etc. These conditions may be life-threatening, e.g., trachea-oesophageal fistula, critical pulmonary stenosis, etc. and require immediate surgical intervention. Some, e.g., hydrocephalus, may need intervention as soon as the patient is fit for surgery. Some, e.g., patent ductus arteriosus need 'wait and watch' policy up to a certain age in the hope of spontaneous recovery. Another extremely important category is that of patients where the operative intervention is done based on their age. Almost all the congenital anomalies coming under care of a plastic surgeon are operated as elective surgery (many as multiple stages of correction) at appropriate ages. There are advantages and disadvantages of intervention at different ages. In this article, we present a review of optimal timings, along with reasoning, for surgery of many of the common congenital anomalies which are treated by plastic surgeons. Obstetricians, paediatricians and general practitioners/family physicians, who most often are the first ones to come across such children, must know to guide the parents appropriately and convincingly impress upon the them as to why their child should not be operated immediately and also the consequences of too soon or too late.

Decreased Tiam1-mediated Rac1 activation is responsible for impaired directional persistence of chondrocyte migration in microtia.

The human auricle has a complex structure, and microtia is a congenital malformation characterized by decreased size and loss of elaborate structure in the affected ear with a high incidence. Our previous studies suggest that inadequate cell migration is the primary cytological basis for the pathogenesis of microtia, however, the underlying mechanism is unclear. Here, we further demonstrate that microtia chondrocytes show a decreased directional persistence during cell migration. Directional persistence can define a leading edge associated with oriented movement, and any mistakes would affect cell function and tissue morphology. By the screening of motility-related genes and subsequent confirmations, active Rac1 (Rac1-GTP) is identified to be critical for the impaired directional persistence of microtia chondrocytes migration. Moreover, Rho guanine nucleotide exchange factors (GEFs) and Rho GTPase-activating proteins (GAPs) are detected, and overexpression of Tiam1 significantly upregulates the level of Rac1-GTP and improves directional migration in microtia chondrocytes. Consistently, decreased expression patterns of Tiam1 and active Rac1 are found in microtia mouse models, Bmp5se/J and Prkralear-3J/GrsrJ. Collectively, our results provide new insights into microtia development and therapeutic strategies of tissue engineering for microtia patients.

BMP signaling maintains auricular chondrocyte identity and prevents microtia development by inhibiting protein kinase A.

Elastic cartilage constitutes a major component of the external ear, which functions to guide sound to the middle and inner ears. Defects in auricle development cause congenital microtia, which affects hearing and appearance in patients. Mutations in several genes have been implicated in microtia development, yet, the pathogenesis of this disorder remains incompletely understood. Here, we show that Prrx1 genetically marks auricular chondrocytes in adult mice. Interestingly, BMP-Smad1/5/9 signaling in chondrocytes is increasingly activated from the proximal to distal segments of the ear, which is associated with a decrease in chondrocyte regenerative activity. Ablation of Bmpr1a in auricular chondrocytes led to chondrocyte atrophy and microtia development at the distal part. Transcriptome analysis revealed that Bmpr1a deficiency caused a switch from the chondrogenic program to the osteogenic program, accompanied by enhanced protein kinase A activation, likely through increased expression of Adcy5/8. Inhibition of PKA blocked chondrocyte-to-osteoblast transformation and microtia development. Moreover, analysis of single-cell RNA-seq of human microtia samples uncovered enriched gene expression in the PKA pathway and chondrocyte-to-osteoblast transformation process. These findings suggest that auricle cartilage is actively maintained by BMP signaling, which maintains chondrocyte identity by suppressing osteogenic differentiation.

The utilization of three-dimensional imaging and three-dimensional-printed model in autologous microtia reconstruction.

Background: The use of three-dimensional (3D) technology helps surgeons in performing autologous microtia reconstruction due to more accurate measurements and a better precision template model. However, the technical aspects of using a 3D imaging and 3D-printed model and the difference in outcomes postoperatively remain poorly reviewed. Purpose: This systematic review aimed to provide the current evidence of the benefit and technical aspects of using 3D technology in autologous microtia reconstruction. Method: A systematic literature search was conducted across multiple databases: Medline, Embase, Google Scholar, and Central until June 2022. Studies that evaluated the use of 3D imaging or 3D-printed models for autogenous microtia reconstruction were selected. The quality of the included studies was also assessed with respect to the study design. Result: A systematic literature search yielded 17 articles with a combination of observational and case report studies. Overall, 3D imaging showed a precise measurement for preoperative costal cartilage assessment. Compared to the 2D template, the utilization of a 3D-printed template provided a higher similarity rate relative to the unaffected ear, higher patient and surgeon satisfaction, and lower surgical time. Most 3D templates were fabricated using polylactic acid material on fused deposition modelling printers. The template costs were ranging from $1 to $4.5 depending on the material used. Conclusion: 3D imaging and 3D-printed templates could improve the outcome of autologous microtia reconstruction. However, the quality of the existing evidence remains low due to the heterogeneity of the reported outcomes. Further studies with more adequate comparability and defined outcomes are still required.

Multi-omics analysis of a case of congenital microtia reveals aldob and oxidative stress associated with microtia etiology.

BACKGROUND: Microtia is reported to be one of the most common congenital craniofacial malformations. Due to the complex etiology and the ethical barrier of embryonic study, the precise mechanisms of microtia remain unclear. Here we report a rare case of microtia with costal chondrodysplasia based on bioinformatics analysis and further verifications on other sporadic microtia patients. RESULTS: One hundred fourteen deleterious insert and deletion (InDel) and 646 deleterious SNPs were screened out by WES, candidate genes were ranked in descending order according to their relative impact with microtia. Label-free proteomic analysis showed that proteins significantly different between the groups were related with oxidative stress and energy metabolism. By real-time PCR and immunohistochemistry, we further verified the candidate genes between other sporadic microtia and normal ear chondrocytes, which showed threonine aspartase, cadherin-13, aldolase B and adiponectin were significantly upregulated in mRNA levels but were significantly lower in protein levels. ROS detection and mitochondrial membrane potential (∆ Ψ m) detection proved that oxidative stress exists in microtia chondrocytes. CONCLUSIONS: Our results not only spot new candidate genes by WES and label-free proteomics, but also speculate for the first time that metabolism and oxidative stress may disturb cartilage development and this might become therapeutic targets and potential biomarkers with clinical usefulness in the future.

Minimally Invasive Costal Cartilage Harvesting Incision for Chest Deformity in Microtia Reconstruction.

BACKGROUND: Chest deformity is a potential complication associated with auricular reconstruction using autologous costal cartilage. The impact of the incision size employed for costal cartilage harvesting on chest deformities remains unclear. This study aimed to investigate the correlation between the incision size used for harvesting costal cartilage and the occurrence of chest deformities. METHODS: We retrospectively analyzed patients who underwent ear reconstruction using autologous costal cartilage between June 2021 and September 2022. The patients were categorized into two groups based on the size of the costal cartilage incision: large and small. Chest computed tomography (CT) was performed 18-24 months postoperatively, followed by three-dimensional color map quantification to assess the degree of asymmetry of the chest surface. Subsequently, quantitative data analysis was performed to compare the extent of chest asymmetry between the large- and small-incision groups. The Visual Analog Scale (VAS) was used to assess patient satisfaction with chest morphology. RESULTS: This study included 62 patients, with an equal distribution of 31 in each group. The mean asymmetry value of the small and large incision groups was -3.15 ± 1.88 and -5.27 ± 3.63, respectively. Moreover, the mean VAS score for the small and large incision groups was 7.48 ± 0.72 and 5.09 ± 0.94, respectively. Statistically significant differences were observed between the two groups. CONCLUSIONS: Small incision costal cartilage harvesting can effectively alleviate the severity of chest deformities and significantly enhance patient satisfaction. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

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.

The impact of national health insurance on the cost of auricular reconstruction with skin expansion for microtia in China: A single-center retrospective study based on 1290 surgeries.

BACKGROUND: Congenital microtia presents challenges that encompass physical disabilities and psychosocial distress. It is reported that people with low income have a higher possibility of giving birth to babies with congenital malformations. At the end of June 2023, auricular reconstruction was partially incorporated into national health insurance in our hospital. METHODS: Briefly, 1290 surgeries, including stage-I and stage-II auricular reconstruction with tissue expansion were performed in 2023, involving 779 patients. Patient data, including age, sex, length of stay, residence, and costs, were retrieved from the electronic medical record system. The final cost before and after health insurance coverage, as well as the medical insurance reimbursement ratio in each province and municipality were statistically analyzed. RESULTS: Following insurance coverage, a significant increase in the number of surgeries was observed (514 [39.84%] vs. 776 [60.16%], χ2 = 45.99, p = 0.000), with notable reductions in out-of-pocket costs for unilateral and bilateral stage-I and -II auricular reconstructions ($3915.01 vs. $6645.28, p < 0.05; $11546.80 vs. $5198.08, p < 0.05). Disparities in reimbursement rates across regions were evident, but showed no correlation to the local GDP per capita. There was a positive correlation between the length of stay and inpatient cost. Patient's age was not related to the inpatient cost, but to the length of stay. CONCLUSION: The health insurance coverage for microtia treatment significantly alleviated financial burdens on the patients' family and increased the number of auricular reconstruction surgeries. These findings underscore the critical role of insurance coverage in enhancing healthcare accessibility and affordability for patients with congenital microtia.

Tablet-based Augmented reality and 3D printed templates in fully guided Microtia Reconstruction: a clinical workflow.

BACKGROUND: Microtia is a congenital malformation of the auricle that affects approximately 4 of every 10,000 live newborns. Radiographic film paper is traditionally employed to bidimensionally trace the structures of the contralateral healthy ear in a quasi-artistic manner. Anatomical points provide linear and angular measurements. However, this technique proves time-consuming, subjectivity-rich, and greatly dependent on surgeon expertise. Hence, it's susceptible to shape errors and misplacement. METHODS: We present an innovative clinical workflow that combines 3D printing and augmented reality (AR) to increase objectivity and reproducibility of these procedures. Specifically, we introduce patient-specific 3D cutting templates and remodeling molds to carve and construct the cartilaginous framework that will conform the new ear. Moreover, we developed an in-house AR application compatible with any commercial Android tablet. It precisely guides the positioning of the new ear during surgery, ensuring symmetrical alignment with the healthy one and avoiding time-consuming intraoperative linear or angular measurements. Our solution was evaluated in one case, first with controlled experiments in a simulation scenario and finally during surgery. RESULTS: Overall, the ears placed in the simulation scenario had a mean absolute deviation of 2.2 ± 1.7 mm with respect to the reference plan. During the surgical intervention, the reconstructed ear was 3.1 mm longer and 1.3 mm wider with respect to the ideal plan and had a positioning error of 2.7 ± 2.4 mm relative to the contralateral side. Note that in this case, additional morphometric variations were induced from inflammation and other issues intended to be addressed in a subsequent stage of surgery, which are independent of our proposed solution. CONCLUSIONS: In this work we propose an innovative workflow that combines 3D printing and AR to improve ear reconstruction and positioning in microtia correction procedures. Our implementation in the surgical workflow showed good accuracy, empowering surgeons to attain consistent and objective outcomes.

Comprehensive analysis of donor-site chest deformities after autologous costal cartilage microtia reconstruction: A systematic review.

BACKGROUND: Autologous costal cartilage has gained widespread acceptance as an important material for ear reconstruction in patients with microtia. Despite its recognition as being "worth the trade-off," attention should be directed toward donor-site deformities. This systematic review focused on existing English literature related to microtia reconstruction and aimed to reveal the incidence of chest wall deformities and assess the effectiveness of the various proposed surgical techniques aimed at reducing donor-site morbidities. METHODS: A comprehensive search was conducted on Pubmed and OVID using the keywords "microtia," and "chest deformity" or "rib harvest." Articles were screened based on predefined inclusion and exclusion criteria. Data acquisition encompassed patient demographics, employed surgical techniques, methods for evaluating chest deformity, and incidence of associated complications. RESULTS: Among the 362 identified articles, 21 met the inclusion criteria. A total of 2600 cases involving 2433 patients with microtia were analyzed in this review. Perichondrium preservation during cartilage harvesting led to a significant reduction in chest deformities. However, the wide incidence range (0% to 50%) and the lack of specific assessment methods suggested potential underestimation. Computed tomography revealed reduced chest wall growth in the transverse and sagittal directions, resulting in decreased thoracic area. Innovative surgical techniques have shown promising results in reducing chest deformities. CONCLUSIONS: Although a quantitative analysis was not feasible, objective evidence of deformities was established through computed tomography scans. This analysis highlighted the need for dedicated studies with larger sample sizes to further advance our understanding of chest wall deformities in microtia reconstruction.

Genotype-phenotype associations in microtia: a systematic review.

BACKGROUND: Microtia is a congenital ear malformation that can occur as isolated microtia or as part of a syndrome. The etiology is currently poorly understood, although there is strong evidence that genetics has a role in the occurrence of microtia. This systematic review aimed to determine the genes involved and the abnormalities in microtia patients' head and neck regions. METHODS: We used seven search engines to search all known literature on the genetic and phenotypic variables associated with the development or outcome of microtia. The identified publications were screened and selected based on inclusion and exclusion criteria and assessed for methodological quality using the Joanna Briggs Institute (JBI) critical appraisal tools. We found 40 papers in this systematic review with phenotypic data in microtia involving 1459 patients and 30 articles containing genetic data involved in microtia. RESULT: The most common accompanying phenotype of all microtia patients was external ear canal atresia, while the most common head and neck abnormalities were the auricular, mental, and oral regions. The most common syndrome found was craniofacial microsomia syndrome. In the syndromic microtia group, the most common genes were TCOF1 (43.75%), SIX2 (4.69%), and HSPA9 (4.69%), while in the non-syndromic microtia group, the most frequently found gene was GSC exon 2 (25%), FANCB (16.67%), HOXA2 (8.33%), GSC exon 3 (8.33%), MARS1 (8.33%), and CDT1 (8.33%). CONCLUSIONS: Our systematic review shows some genes involved in the microtia development, including TCOF1, SIX2, HSPA9, GSC exon 2, FANCB, HOXA2, GSC exon 3, MARS1, and CDT1 genes. We also reveal a genotype-phenotype association in microtia. In addition, further studies with more complete and comprehensive data are needed, including patients with complete data on syndromes, phenotypes, and genotypes.

[Cochlear implantation through retro-facial approach with congenital microtia malformation with facial nerve deformity: a case report].

The difficulty of cochlear implantation in patients with congenital microtia is usually increased due to the vague anatomical marks and facial nerve malformation. The common types of facial nerve malformation include facial nerve bony cover loss, aberrant position, and bifurcation malformation. Bifurcation malformation may obscure the oval window, press against stapes, and bifurcate in the vestibular window while obscuring the round window. It is important to correctly identify the facial nerve and choose a reasonable surgical approach to avoid postoperative complications. This article describes a case of profound sensorineural hearing loss due to facial nerve malformation in our institution. The patient underwent cochlear implantation through the retro-facial approach. There was no facial nerve injury or dysfunction symptoms such as facial paralysis and hemifacial spasm 2 years after the operation, and the cochlear implant works well. The score of the categories of the auditory performance（CAP） questionnaire was 7, and the score of the speech intelligibility rating（SIR） questionnaire was 4. When the round window cannot be exposed through the facial recess approach during surgery, the retro-facial approach is a feasible method. To avoid facial nerve injury, a thin-section CT of the temporal bone should be performed before the middle and inner ear surgery for patients with facial nerve malformation, and the intraoperative facial nerve monitor should be used to clarify the course of the facial nerve to avoid injury.

Retrospective study on unilateral polyotia combined with microtia utilizing the technique of preserving residual ear tissue.

BACKGROUND: The presence of polyotia in individuals with microtia is a rare deformity. Due to the intricate structure of the auricle, uncertain etiology, and challenging corrective techniques, it has always been a focal point in the field of plastic surgery. The present study presents a technique for correcting the combination of polyotia and microtia by utilizing residual ear tissue as graft material. METHODS: The retrospective study included 23 patients with polyotia and microtia from 2018 to 2022. The residual ear tissue was used to rectify auricular deformities in all patients. The patients were instructed to evaluate the satisfaction of the auricle shape using a visual analog scale (VAS) both before and 6 months after the surgical procedure. The esthetic outcomes of auricle subunits were simultaneously assessed by a senior physician pre- and postoperatively. RESULTS: The mean duration of follow-up in this study was 8.73 months. The preoperative VAS satisfaction score was recorded as 2.26 ± 0.86, while the post-operative VAS score significantly increased to 7.86 ± 0.86. The preoperative auricle esthetic outcomes score was recorded as 9.95 ± 1.74, while the post-operative score significantly increased to 24.04 ± 2.16. The follow-up period did not present any cases of flap necrosis, hematoma, infection, or wound dehiscence. CONCLUSION: The study demonstrates that comprehensive utilization of residual auricular tissue can lead to optimal outcomes in correcting polyotia with concha-type microtia. The utilization of residual ear tissue can be maximized to streamline the operation, minimize bodily harm, and enhance patient satisfaction.

Co-culture of RhoA-overexpressed microtia chondrocytes and adipose-derived stem cells in the construction of tissue-engineered ear-shaped cartilage.

Microtia is a congenital auricle dysplasia with a high incidence and tissue engineering technology provides a promising strategy to reconstruct auricles. We previously described that the engineered cartilage constructed from microtia chondrocytes exhibited inferior levels of biochemical and biomechanical properties, which was proposed to be resulted of the decreased migration ability of microtia chondrocytes. In the current study, we found that Rho GTPase members were deficient in microtia chondrocytes. By overexpressing RhoA, Rac1, and CDC42, respectively, we further demonstrated that RhoA took great responsibility for the decreased migration ability of microtia chondrocytes. Moreover, we constructed PGA/PLA scaffold-based cartilages to verify the chondrogenic ability of RhoA overexpressed microtia chondrocytes, and the results showed that overexpressing RhoA was of limited help in improving the quality of microtia chondrocyte engineered cartilage. However, coculture of adipose-derived stem cells (ADSCs) significantly improved the biochemical and biomechanical properties of engineered cartilage. Especially, coculture of RhoA overexpressed microtia chondrocytes and ADSCs produced an excellent effect on the wet weight, cartilage-specific extracellular matrix, and biomechanical property of engineered cartilage. Furthermore, we presented that coculture of RhoA overexpressed microtia chondrocytes and ADSCs combined with human ear-shaped PGA/PLA scaffold and titanium alloy stent fabricated by CAD/CAM and 3D printing technology effectively constructed and maintained auricle structure in vivo. Collectively, our results provide evidence for the essential role of RhoA in microtia chondrocytes and a developed strategy for the construction of patient-specific tissue-engineered auricular cartilage.

Identification of a novel phenotype of external ear deformity related to Coffin-Siris syndrome-9 and literature review.

De novo germline variants of the SRY-related HMG-box 11 gene (SOX11) have been reported to cause Coffin-Siris syndrome-9 (CSS-9), a rare congenital disorder associated with multiple organ malformations, including ear anomalies. Previous clinical and animal studies have found that intragenic pathogenic variant or haploinsufficiency in the SOX11 gene could cause inner ear malformation, but no studies to date have documented the external ear malformation caused by SOX11 deficiency. Here, we reported a Chinese male with unilateral microtia and bilateral sensorineural deafness who showed CSS-like manifestations, including dysmorphic facial features, impaired neurodevelopment, and fingers/toes malformations. Using trio-based whole-exome sequencing, a de novo missense variant in SOX11 (NM_003108.4: c.347A>G, p.Y116C) was identified and classified as pathogenic variant as per American College of Medical Genetics guidelines. Moreover, a systematic search of the literature yielded 12 publications that provided data of 55 SOX11 intragenic variants affecting various protein-coding regions of SOX11 protein. By quantitatively analyzing phenotypic spectrum information related to these 56 SOX11 variants (including our case), we found variants affecting different regions of SOX11 protein (high-mobility group [HMG] domain and non-HMG regions) appear to influence the phenotypic spectrum of organ malformations in CSS-9; variants altering the HMG domain were more likely to cause the widest range of organ anomalies. In summary, this is the first report of CSS with external ear malformation caused by pathogenic variant in SOX11, indicating that the SOX11 gene may be not only essential for the development of the inner ear but also critical for the morphogenesis of the external ear. In addition, thorough clinical examination is recommended for patients who carry pathogenic SOX11 variants that affect the HMG domain, as these variants may cause the widest range of organ anomalies underlying this condition.

Perioperative position management of 46 cases with simultaneous bilateral auricle reconstruction: A summary of experience.

OBJECTIVES: The primary problem in simultaneous bilateral auricle reconstruction is the fragility of the reconstructed ear structure. Postoperative pressure is strictly prohibited to ensure the operation's effectiveness. The study aimed to summarize the experience of perioperative postural management in simultaneous bilateral auricular reconstruction. METHOD: This study summarizes the experience of perioperative postural management, providing preoperative sleeping posture adaptability training, neck movement training, standardization of the head position angles and the head suspension time in surgery, using protective headrests, paying attention to the transfer and handover procedures, and using specially designed pillows. RESULTS: The comprehensive nursing approach in simultaneous bilateral auricular reconstruction significantly reduced complications, improved patient comfort, and optimized postoperative adaptation. Preoperative posture training, standardized intraoperative head positions, and vigilant postoperative care played pivotal roles, demonstrating positive outcomes in 46 cases. DISCUSSION: Perioperative position management can reduce the risk of complications and pressure injuries, improving patients' postoperative comfort, emotional state, tolerance, and adaptability. CONCLUSION: All ears were viable and in good shape after long-term follow-up. The experiences discussed in this study can be broadly applied to technically mature ear reconstruction teams.

Salvage of Infected Alloplastic Ear Reconstructions via Negative Pressure Wound Therapy.

This is the first description of Negative Pressure Wound Therapy (NPWT) use in rescuing alloplastic ear reconstructions. Previously considered a sign of certain impending failure, severe infections with frank purulence can be salvaged. As a more recently developed technique, porous polyethylene (PPE) ear reconstruction provides benefits when compared to rib techniques. Increasing surgeon awareness of complication management may lead to further adoption of the technique and improve reconstructive results. Described herein are two cases of draining infections following PPE ear reconstruction that were salvaged with satisfactory results. Laryngoscope, 2024.

Prograde transposition for anteriorly low-set earlobe in lobule-type microtia reconstruction.

BACKGROUND: Lobule transposition, a common procedure in auricle reconstruction, has been successfully performed over the past few decades. However, the transposition methods for unilateral microtia with evident asymmetry of bilateral earlobe positions still remain a challenge. The objective of this study was to investigate the application of prograde transposition for anteriorly low-set earlobes. METHOD: A total of 25 patients with lobule-type microtia with anteriorly low-set residual earlobe underwent prograde transposition during auricle reconstruction between 2020 and 2022. The post-operative earlobe aesthetic assessment and patient satisfaction were evaluated, and the data on any complications that occurred when followed-up were collected. This study provides a comprehensive analysis and summary of the techniques used in earlobe transposition for auricular reconstruction. RESULTS: The patients with evident asymmetry between the residual and healthy earlobes were usually concomitant with hemifacial microsomia and the residual ear was located in the anterior and lower region. No instances of flap necrosis, hematoma, or wound dehiscence were observed following auricular reconstruction. The mean aesthetic score of the auricle was 3.52, with 23 patients attaining good or excellent aesthetic outcomes. The mean Visual Analog Scale satisfaction score was 3.68, with 24 patients reporting relative satisfaction or satisfaction. CONCLUSION: The prograde transposition of anteriorly low-set earlobe in lobule-type microtia reconstruction can effectively ensure adequate blood supply, enhance aesthetic appearance, and significantly improve patient satisfaction.

A 76-base pair duplication within the enhancer region of the HMX1 gene causes sheep microtia.

Sheep congenital microtia is characterized by underdeveloped ears and provides an ideal basis for studying human microtia. This study identified the causal mutation and regulatory mechanisms underlying this disorder. Whole-genome association analysis was conducted using 23 ear tissue samples from sheep with microtia and 28 samples from normal-eared sheep. A significant correlation was found between microtia and a 76-base pair duplication in the enhancer region of the HMX1 gene. Further analysis of offspring phenotypes confirmed an autosomal dominant inheritance pattern. Genotypic analysis showed that individuals that are homozygous for this duplication were earless, heterozygous individuals exhibited shortened ears, and wild-type individuals had normal ears. Moreover, luciferase assays confirmed that this duplication increased HMX1 gene expression, and duplication knock-in mice also exhibited shorter and narrower external ears compared to wild-type mice. Transcriptomic analysis further demonstrated that this duplication enhanced HMX1 gene expression in animal models. This study characterized the causal regulatory mutation underlying sheep microtia.

Anatomical variant of the superficial temporal artery in temporoparietal fascia flap for microtia reconstruction.

BACKGROUND: Single-stage microtia auricular reconstruction is becoming more relevant. The determining factor is a temporoparietal fascia flap (TPF) with both branches of the superficial temporal artery (STA). There are not many studies regarding vascular branching in people with microtia. METHODS: We conducted an anatomical study on the TPF flap harvested during single-stage endoscopic-assisted microtia auricular reconstruction from May 2018 to July 2021. We observed the flaps under endoscopic and surgical microscopes to determine several variables (vascular size, number of frontal/parietal branches, distance from the branching location to the estimated external ear canal, distance from the frontal artery to projected course of facial nerve's frontal branch, etc.). RESULTS: The study included 55 flaps from 54 patients. Of the 55 flaps, 50 (90.9%) had a parietal branch, and all 55 (100%) had a frontal branch with a mean diameter of 0.98 and 0.91 mm, respectively. Regarding the frontal artery, 1.8%, 25.5%, 50.9%, 16.35% and 5.45% had 0-4 traverse frontal branch(es), respectively. The mean distance from the frontal artery to the estimated course of the frontal nerve was 10.56 mm. Parietal artery absence is more likely in patients with severe hemifacial microsomia or STA trunk go under the auricular cartilage remnants (p < 0.05). Either frontal or parietal artery absence or small diameter can cause necrosis. Frontal arteries travelling near the frontal nerve may result in post-operative nerve palsy. CONCLUSIONS: Microtia auricular reconstructive surgery is always a big challenge for plastic surgeons. Anatomical variants are common. A detailed anatomical description of the STA, with the help of microsurgery and endoscopy, allows arterial-based flap designing and harvest, which tremendously improves surgical success rate by diminishing flap necrosis and nerve damage. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.