Exploring mismatch negativity in children with congenital Microtia-Atresia: A Preliminary study.

BACKGROUND: To investigate the characteristics of mismatch negativity (MMN) in terms of latency and amplitude in children with bilateral congenital microtia using a Bone conduction implant (Bonebridge), and to explore the relationship between cortical level auditory discrimination, speech perception, and psychosocial well-being. METHODS: This descriptive, observational, cross-sectional study compared three groups: eight children with bilateral congenital microtia and Bonebridge implants (bilateral group), eight children with unilateral congenital microtia and no hearing aids (unilateral group), and eight children with normal hearing (NH group). Participants underwent MMN evaluation using a classic oddball paradigm with a pure tone burst stimulus, featuring a 1000 Hz standard stimulus and a 1200 Hz deviant stimulus, presented in a sound field at 65 dBHL. Additionally, speech perception tests, the Meaningful Use of Speech Scale (MUSS), and psychosocial status questionnaires, including the Social Anxiety Scale for Children (SASC) and the Children's Loneliness Scale (CLS), were administered to all subjects. RESULTS: The bilateral group's average MMN latency was 241.23 ± 29.47 ms, and the unilateral group's was 209.96 ± 54.32 ms, both significantly longer than the NH group's 146.05 ± 15.73 ms (p < 0.0001, F=3.509, 95 % CI 68.09 to 122.3 and p = 0.0097, F=11.92, 95 % CI 18.07 to 109.8, respectively). However, no significant difference was found in MMN latency between the bilateral and unilateral groups (p = 0.202, F=3.397, 95 % CI -18.84 to 81.36). The unilateral group scored significantly higher on the MUSS (38.63 ± 1.41 vs. 30.75 ± 3.80, p = 0.0001, F=7.276, 95 % CI -11.16 to -4.590), had lower CLS scores (47.13 ± 8.13 vs. 58.25 ± 8.39, p = 0.024, F=1.065, 95 % CI 1.652 to 20.60), and lower SASC scores (4.13 ± 2.09 vs. 6.50 ± 2.25, p = 0.062, F=1.204, 95 % CI -0.138 to 4.89) compared to the bilateral group. MMN latency in the bilateral group correlated with SASC scores. CONCLUSION: The MMN latency in congenital microtia patients may serve as an indicator of central auditory discrimination capabilities. In children with bilateral congenital microtia and Bonebridge implants, MMN latency can reflect social anxiety conditions to a certain degree.

Predictors of 30-day complications, readmission, and postoperative length of stay in children undergoing autologous rib grafting for microtia.

BACKGROUND: Predictors of outcomes in pediatric microtia surgery are not well understood within the current literature. A multi-institutional database study may reveal insights into these predictors. OBJECTIVES: To explore the predictors of 30-day complications, 30-day readmission, and postoperative length of stay (PLOS) in pediatric microtia patients undergoing autologous rib grafting. METHODS: The Pediatric National Surgical Quality Improvement Program was queried for details on patients with microtia (ICD-9/10 744.23/Q17.2) who underwent autologous rib grafting (CPT 21230) between 2012-2021. Demographics, comorbidities, inpatient status, 30-day complications, PLOS, and 30-day readmissions were analyzed. Statistical analyses were performed to compare the preoperative characteristics with postoperative outcomes. RESULTS: Overall, 667 patients met the inclusion criteria. Sixty-three (9.4%) had at least one complication, and 19 (2.9%) were readmitted. Univariate analysis showed that inpatient status (p = 0.011) and race (p = 0.023) were associated with higher complication rates. Multivariate analysis revealed that outpatient status was associated with significantly lower odds of complications (OR: 0.49, 95% CI [0.27, 0.87], p = 0.018), and developmental delay was associated with higher odds of 30-day readmission (OR: 2.80, 95% CI [1.05, 7.17], p = 0.036). Longer operative time was associated with older age (13.9% increase per five-year age increase, p < 0.001) and inpatient status (35.3% increase, p < 0.001). PLOS was shorter for outpatients (45.45% shorter, p < 0.001) and cases performed by plastic surgeons (14.2% shorter, p < 0.001). CONCLUSION: Microtia reconstruction using autologous cartilage is a relatively safe procedure with low complication and readmission rates. Significant predictors of postoperative outcomes include inpatient status, race, developmental delay, and age. These findings highlight the importance of considering these factors in surgical planning and patient counseling.

The ideal range of laser hair removal for microtia patients undergoing two-stage ear reconstruction.

Although the technologies for auricular reconstruction in microtia have improved, issues such as low hairlines or excessive hair growth can still pose aesthetic problems for the reconstructed ear. Laser depilation has been reported as a solution for hair problems. However, few studies have discussed the appropriate region for hair removal. A retrospective analysis was performed on 276 patients with unilateral microtia who underwent the Nagata two-stage ear reconstruction. The gender ratio of male to female was 2.5 (198 males/78 females). Intense pulsed light depilation was used to remove hair. To determine the proper hair removal area, we measured the extent of hair removal. Before the first stage, the average vertical distance between the upper point (after localization) and hairline was 3.42 ± 4.75 mm (-10-20 mm). After the first stage, the average vertical distance between the upper point of the reconstructed ear and the hairline was 1.27 ± 2.41 mm (-10-15 mm). By using chi-square test to assess differences in hair removal success rates among various regions, we aimed to identify the suitable depilation region. Before the first stage, a depilation vertical distance ≥ 10 mm led to a 92.1% success rate. After the first stage surgery, among the patients needing additional hair removal, a vertical depilation distance ≥ 4 mm resulted in an 81.3% success rate. Based on our observation, we suggested that a depilation region of ≥ 10 mm (before the first surgery) or ≥ 4 mm (after the first surgery) would be the ideal range for laser hair removal.

Auricle reconstruction with autologous costal cartilage versus polyethylene implants in microtia patients: a meta-analysis.

BACKGROUND: Auricle reconstruction is among the most challenging procedures in plastic and reconstructive surgery, and the choice of framework material is a critical decision for both surgeons and patients. This meta-analysis compared the outcomes of autologous auricle reconstruction using costal cartilage with those of alloplastic reconstruction using porous polyethylene implants. METHODS: A literature review was conducted using the PubMed and Embase databases to retrieve articles published between January 2000 and June 2024. The outcomes analyzed included postoperative complications such as framework exposure, infection, skin necrosis, hematoma, and hypertrophic scars, as well as patient satisfaction. The proportions of reconstructive outcomes from each selected study were statistically analyzed using the "metaprop" function in R software. RESULTS: Fourteen articles met our inclusion criteria. The group undergoing polyethylene implant reconstruction exhibited higher rates of framework exposure, infection, and skin necrosis, whereas the autologous reconstruction group experienced higher rates of hematoma and hypertrophic scars. Of all the complications, framework exposure was the only one to show a statistically significant difference between the two groups (p < 0.0001). In terms of patient satisfaction, those who underwent autologous cartilage reconstruction reported a higher rate of satisfaction, although this difference did not reach statistical significance in the meta-analysis (p = 0.076). CONCLUSION: There is no statistically significant difference in postoperative complications such as infection, hematoma, skin necrosis, and hypertrophic scars between auricle reconstructions using autologous costal cartilage and those using polyethylene implants. However, reconstructions with polyethylene implants show a significantly higher rate of framework exposure.

Superficial temporal artery branching pattern in single stage auricular reconstruction: A novel classification.

INTRODUCTION: The two most severe complications of single-stage, porous polyethene microtia reconstruction are flap necrosis/framework exposure and frontal nerve paralysis. To reduce these risks, require a temporoparietal fascia (TPF) flap that includes both the parietal and frontal branches of the superficial temporal artery (STA) while sparing the nerve. We propose a classification that helps minimize said complications. MATERIAL AND METHODS: Fifty-five TPF flaps of 54 microtia patients who underwent single-stage auricular reconstruction from May 2018 to July 2021 were studied. Flaps were harvested using endoscopic techniques. The parietal and frontal branch characteristics and measurements were obtained using a microscope/endoscope. RESULTS: The frontal artery might have 1 to 4 branches. If they were close to Pitanguy's line (≤5 mm), there would be a high risk of nerve damage. Parietal (P) and frontal (F) artery diameters <0.5 mm were risk factors for partial flap necrosis. Based on this observation, we proposed 0.5 mm as the diameter threshold to determine whether an arterial branch is hypoplasia or sufficient. From this study, a new classification of STA branching pattern was proposed with five types: PF1 (23.6 %), PF2 (43.6 %), pF1 (3.6 %), pF2 (12.8 %), and Pf (16.4 %); where P/F indicates sufficient branches, p/f indicates absent or hypoplasia ones, and the number indicates single or multiple frontal artery branching. CONCLUSION: The risk of flap necrosis and frontal nerve damage is due to abnormalities of the frontal artery of the STA in the TPF flap. Understanding the anatomical classification with clear visualization during flap harvest ensures a successful outcome.

Evaluation of mastoid volume and dimensions in unilateral microtia patients: retrospective study using High Resolution Computed Tomography (HRCT).

OBJECTIVE: The aim of this study is to evaluate mastoid volume and dimensions in patients with unilateral microtia using High-Resolution Computed Tomography (HRCT) to enhance the precision of reconstructive surgical planning. METHODS: A retrospective analysis of HRCT mastoid scans from patients with unilateral microtia was carried out at Cipto Mangunkusumo General Hospital between May 2020 and August 2022. Parameters such as mastoid volume, height, and surface area were measured at the ear canal, Superior Semicircular Canal (SCC), and lateral SCC levels. RESULTS: The analysis revealed statistically significant decreases in median mastoid air cell volume and mastoid bone volume in the affected ears compared to contralateral ears (p =  0.0312 and p =  0.02, respectively). Additionally, decreased mastoid height and surface areas at the ear canal and superior SCC levels were identified in affected ears (p <  0.05). CONCLUSIONS: Patients with unilateral microtia have diminished mastoid bone volumetric parameters and dimensions on the affected side. These findings offer critical data for surgeons in preoperative planning, enabling the selection of appropriate reconstructive techniques and providing comprehensive patient counselling. LEVEL OF EVIDENCE: Level 4.

Clinical Analysis and Treatment Strategies About Cartilage Scaffold Exposure After Auricular Reconstruction With the Expanded Two-Flap Method.

Objectives: Soft tissue expansion is one of the main methods for autologous cartilage auricular reconstruction. The aim of this study was to analyze the risk factors for cartilage exposure after this method and to describe a surgical method for this complication. Methods: From January 2018 to December 2020, 853 patients (908 sides) underwent auricular reconstruction with an expanded two-flap method at our center. Thirty-two patients experienced cartilage exposure postoperatively. These patients were set as the case group, and 1:1 matched sampling was performed among patients who did not have cartilage exposure. The matched sample of 32 cases was set as the control group. All 64 patients were evaluated according to the Orbit, Mandible, Ear, Nerve, and Soft tissue (OMENS) classification system to analyze the correlation between cartilage exposure and hemifacial microsomia (HFM) and OMENS subtypes. The complication was repaired with superficial temporal fascial flap combined with skin graft. Results: HFM might be a risk factor for scaffold cartilage exposure, and there was a significant correlation between cartilage exposure and orbital malformation, facial nerve dysplasia, and soft tissue developmental malformation. The use of a superficial temporal fascial flap combined with a split-thickness skin graft to repair the complication achieved satisfactory outcomes. Conclusions: There is a correlation between cartilage scaffold exposure and the severity of HFM. Temporoparietal fascial flap transfer combined with skin grafting proved to be an effective method for cartilage exposure.

Hemifacial Microsomia Surgical Approach and Anotia Reconstruction: A Case Report.

BACKGROUND/AIM: Hemifacial microsomia (HFM) is the second most common congenital anomaly of the craniomaxillofacial region after the cleft lip and palate. This malformation is characterized by unilateral mandible and ear hypoplasia. Treatment varies and depends on different phenotypes. Severe deficiencies require multiple reconstructive surgeries to address facial asymmetries. This study aimed to review the surgical approach and evaluate the postoperative results of a case with right hemifacial microsomia and anotia. CASE REPORT: This is the case of a 35-year-old female patient who, after multiple graft operations in the right mandible due to hemifacial microsomia, was operated for auricle reconstruction. Initially, a three-dimensional custom made Medpor (porex) was used, covered by the superficial temporal fascia. Subsequently, due to inflammation and partial exposure of this porous polyethylene implant (PPI), a temporalis muscular flap along with the deep temporal fascia were used as a salvage operation. Ten months later, the patient underwent deep plane face lift combined with open rhinoplasty. Lefort I osteotomies and transoral lip lengthening through a transection of the levator nasi septi muscle were also performed. Ear helix reconstruction was completed with a rotation scalp flap after tissue expansion. The patient had an uncomplicated postoperative course with an aesthetically acceptable result. CONCLUSION: As a congenital disorder, hemifacial microsomia is present at birth and successful reconstruction is of fundamental importance for the smooth integration of these individuals into society. The multiple asymmetries, the affected topographic area of the face, as well as the onset in neonatal age constitute a challenge for reconstructive surgery.

Auricular growth potential of patients with concha-type microtia after auricular cartilage stretching surgery: A prospective study.

BACKGROUNDS: For patients with concha-type microtia, surgical intervention and the degree of deformity may affect the growth rate of the auricular cartilage, which is different at different ages. This study aimed to explore the auricular growth potential of patients with concha-type microtia at different ages after auricular cartilage stretching surgery. METHODS: A total of 66 patients with unilateral grade II and III concha-type microtia were involved in this prospective cohort study. All patients underwent auricular cartilage stretching surgery. Relevant data were collected before surgery, immediately after surgery, and at the last follow-up. RESULTS: The perimeter, width, and length of auricle, between each follow-up, was statistically significant, which supported the effect of surgery and auricular development. For patients in the grade II group, no statistical significance was found in the difference in the perimeter, width, and length between the affected and normal auricle. For the patients in the grade III group, the difference in the relevant indexes of the affected auricle was significantly different from those of the normal auricle. Between subgroups divided according to their age, the growth potential of affected auricle with the same degree of deformity was statistically significant. CONCLUSIONS: Growth potential of the affected auricle of the grade II group was consistent with that of the normal auricle, which was significantly higher than that of the grade III group. For patients at different ages, auricles grew faster before 3 years of age. Surgical intervention improved the auricular aesthetics and released the auricular growth potential. Thus, surgical intervention should be recommend as early as possible.

One-Year Results of Ear Reconstruction with 3D Printed Implants.

PURPOSE: External ear reconstruction has been a challenging subject for plastic surgeons for decades. Popular methods using autologous costal cartilage or polyethylene still have their drawbacks. With the advance of three-dimensional (3D) printing technique, bioscaffold engineering using synthetic polymer draws attention as an alternative. This is a clinical trial of ear reconstruction using 3D printed scaffold, presented with clinical results after 1 year. MATERIALS AND METHODS: From 2021 to 2022, five adult patients with unilateral microtia underwent two-staged total ear reconstruction using 3D printed implants. For each patient, a patient-specific 3D printed scaffold was designed and produced with polycaprolactone (PCL) based on computed tomography images, using fused deposition modeling. Computed tomography scan was obtained preoperatively, within 2 weeks following the surgery and after 1 year, to compare the volume of the normal side and the reconstructed ear. At 1-year visit, clinical photo was taken for scoring by two surgeons and patients themselves. RESULTS: All five patients had completely healed reconstructed ear at 1-year follow-up. On average, the volume of reconstructed ear was 161.54% of that of the normal side ear. In a range of 0 to 10, objective assessors gave scores 3 to 6, whereas patients gave scores 8 to 10. CONCLUSION: External ear reconstruction using 3D printed PCL implant showed durable, safe results reflected by excellent volume restoration and patient satisfaction at 1 year postoperatively. Further clinical follow-up with more cases and refinement of scaffold with advancing bioprinting technique is anticipated. The study's plan and results have been registered with the Clinical Research Information Service (CRIS No. 3-2019-0306) and the Ministry of Food and Drug Safety (MFDS No. 1182).

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.

3D printing tissue-engineered scaffolds for auricular reconstruction.

Congenital microtia is the most common cause of auricular defects, with a prevalence of approximately 5.18 per 10,000 individuals. Autologous rib cartilage grafting is the leading treatment modality at this stage of auricular reconstruction currently. However, harvesting rib cartilage may lead to donor site injuries, such as pneumothorax, postoperative pain, chest wall scarring, and deformity. Therefore, in the pursuit of better graft materials, biomaterial scaffolds with great histocompatibility, precise control of morphology, non-invasiveness properties are gradually becoming a new research hotspot in auricular reconstruction. This review collectively presents the exploit and application of 3D printing biomaterial scaffold in auricular reconstruction. Although the tissue-engineered ear still faces challenges before it can be widely applied to patients in clinical settings, and its long-term effects have yet to be evaluated, we aim to provide guidance for future research directions in 3D printing biomaterial scaffold for auricular reconstruction. This will ultimately benefit the translational and clinical application of cartilage tissue engineering and biomaterials in the treatment of auricular defects.

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.

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.

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.

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.

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.

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.

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.