A novel algorithm for autologous ear reconstruction

Reconstructive Techniques in Pediatric Congenital Microtia: A Systematic Review and Meta-analysis

Autografts and allografts are commonly used in microtia reconstruction. We aimed to systematically review and compare these reconstructive materials in pediatric congenital microtia reconstruction. A systematic review of the literature was performed. MEDLINE, Embase, PubMed, Web of Science, and CINAHL databases were searched for original studies on congenital microtia reconstruction in pediatric patients since database inception to 2021. Microtia grade was stratified as high or low. Meta-analysis of pooled proportions and continuous variables was performed using inverse variance weighting with a random effects model to compare between the autograft and allograft groups. Sixty-eight studies with a total of 5,546 patients used autografts (n = 5,382) or alloplastic implants (n = 164). Four other studies used prosthesis, cadaveric homografts, or tissue engineering. The allograft group was on average younger than the autograft group (8.4 vs. 11.1 years). There were no syndromic patients in the allograft group, compared to 43% in the autograft group. Patients treated with allografts had higher microtia grade than those treated with autograft (98 vs. 72%). Autografts were more commonly utilized by plastic surgeons and allografts by otolaryngologists (95 vs. 38%). No autografts and 41% of allografts were done concurrently with atresiaplasty or bone conduction implant. Satisfaction rates were similarly high (>90%) with similar complication rates (<10%). Microtia reconstruction using autografts and allografts had similar satisfaction and complication rates. Allografts were preferred for younger patients and concurrent hearing restoration. Further large-scale studies are required to evaluate the long-term efficacy of these reconstructive techniques.

Our Evolution of Approaches to Microtia Reconstruction

Microtia reconstruction is a complex procedure performed by the facial plastic and reconstructive surgeon and requires an expert understanding of the three-dimensional structure of the ear. This article provides an overview of the evolution of microtia reconstruction through history. Techniques pioneered by microtia surgeons Drs. Radford Tanzer, Burt Brent, Satoru Nagata, and Françoise Firmin will be described along with an additional excerpt on the utilization of porous polyethylene (Medpor; Stryker, USA). The objective for the reader is to be able to summarize approaches of each major reconstructive technique, compare the differences in techniques, and gain an understanding of the advantages and disadvantages of each approach.

Optimal surgical timing for ear reconstruction with autologous cartilage: Analysis of the computed tomography scan characteristics of the ribs

BACKGROUND

The approach to constructing the cartilage framework for ear reconstruction is sufficiently established. However, there is still no consensus about the age of initiation of surgical treatment. This study aims to assess the development and growth of the costal cartilage to determine the best age to perform ear reconstruction surgery.

METHODS

Out of 107 patients, we used presurgical treatment data for 40 patients and medical records for 67 patients aged 5-40. Computed tomography (CT) scans were performed, and average parameters were calculated (length, width, thickness, cartilage density, and standard deviation in Hounsfield units) of the cartilaginous part of the 6th, 7th, 8th, and 9th ribs.

RESULTS

The required values were reached at 9-10 years old.

CONCLUSION

The criteria for starting surgical treatment in the Russian population was determined by the width of the 6th-7th ribs synchondrosis, which must be equal to the width of a healthy auricle, and the length of the 8th rib should be longer than 9 cm. Therefore, the optimal age for ear reconstruction with autologous costal cartilage is 10 years and older. However, reconstruction can be made earlier in specific cases, according to height and weight and the preoperative CT scan.

Cost-effective 3D scanning and printing technologies for outer ear reconstruction: current status

Current 3D scanning and printing technologies offer not only state-of-the-art developments in the field of medical imaging and bio-engineering, but also cost and time effective solutions for surgical reconstruction procedures. Besides tissue engineering, where living cells are used, bio-compatible polymers or synthetic resin can be applied. The combination of 3D handheld scanning devices or volumetric imaging, (open-source) image processing packages, and 3D printers form a complete workflow chain that is capable of effective rapid prototyping of outer ear replicas. This paper reviews current possibilities and latest use cases for 3D-scanning, data processing and printing of outer ear replicas with a focus on low-cost solutions for rehabilitation engineering.

Concha-Type Microtia: New Surgical Incision

BACKGROUND

Reconstruction of auricles for conchal-type microtia is challenging but rewarding. Many plastic surgeons consider autogenous rib cartilage as the standard material for framework fabrication. A healthy, scar-free skin envelope and a defined cartilaginous framework are also critical to successful ear reconstruction.

OBJECTIVES

The aim of this study was to improve the outcome of the reconstruction and minimize complications by proposing a new surgical incision.

METHODS

Thirty-three patients who underwent auricular reconstruction of concha-type microtia of various etiologies with the new skin flap incision between 2017 and 2022 were included in the study. Patients' clinical data, detailed surgical techniques, and postoperative care were recorded.

RESULTS

Thirty-three patients (21 male, 12 female) were enrolled in the study. The mean age of the patients was 21.51 years at the time of reconstruction. The microtia was on the right side in 17 cases, on the left side in 12 cases, and 4 cases were bilateral; 12 cases were traumatic amputations of the helical component of the auricle, 11 cases were deformities after a burn, and 10 cases were congenital. The mean follow-up time was 17.43 months. A good initial projection without obvious scarring on the anterior surface of the auricle was achieved, with an overall complication rate of 5.42%.

CONCLUSIONS

The surgical incision recommended in the study improves the final aesthetic result of the technique without any additional surgical risk.

LEVEL OF EVIDENCE: 4

Hypoxia Differentially Affects Chondrogenic Differentiation of Progenitor Cells from Different Origins

Background and Objectives

Ear cartilage malformations are commonly encountered problems in reconstructive surgery, since cartilage has low self-regenerating capacity. Malformations that impose psychological and social burden on one's life are currently treated using ear prosthesis, synthetic implants or autologous flaps from rib cartilage. These approaches are challenging because not only they request high surgical expertise, but also they lack flexibility and induce severe donor-site morbidity. Through the last decade, tissue engineering gained attention where it aims at regenerating human tissues or organs in order to restore normal functions. This technique consists of three main elements, cells, growth factors, and above all, a scaffold that supports cells and guides their behavior. Several studies have investigated different scaffolds prepared from both synthetic or natural materials and their effects on cellular differentiation and behavior.

Methods and Results

In this study, we investigated a natural scaffold (alginate) as tridimensional hydrogel seeded with progenitors from different origins such as bone marrow, perichondrium and dental pulp. In contact with the scaffold, these cells remained viable and were able to differentiate into chondrocytes when cultured in vitro. Quantitative and qualitative results show the presence of different chondrogenic markers as well as elastic ones for the purpose of ear cartilage, upon different culture conditions.

Conclusions

We confirmed that auricular perichondrial cells outperform other cells to produce chondrogenic tissue in normal oxygen levels and we report for the first time the effect of hypoxia on these cells. Our results provide updates for cartilage engineering for future clinical applications.

Integrated microtia and aural atresia management

Objectives

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

Methods

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

Results

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

Cartilage tissue engineering by extrusion bioprinting utilizing porous hyaluronic acid microgel bioinks

3D bioprinting offers an excellent opportunity to provide tissue-engineered cartilage to microtia patients. However, hydrogel-based bioinks are hindered by their dense and cell-restrictive environment, impairing tissue development and ultimately leading to mechanical failure of large scaffoldsin vivo. Granular hydrogels, made of annealed microgels, offer a superior alternative to conventional bioinks, with their improved porosity and modularity. We have evaluated the ability of enzymatically crosslinked hyaluronic acid (HA) microgel bioinks to form mature cartilagein vivo. Microgel bioinks were formed by mechanically sizing bulk HA-tyramine hydrogels through meshes with aperture diameters of 40, 100 or 500µm. Annealing of the microgels was achieved by crosslinking residual tyramines. Secondary crosslinked scaffolds were stable in solution and showed tunable porosity from 9% to 21%. Bioinks showed excellent rheological properties and were used to print different objects. Printing precision was found to be directly correlated to microgel size. As a proof of concept, freeform reversible embedding of suspended hydrogels printing with gelation triggered directly in the bath was performed to demonstrate the versatility of the method. The granular hydrogels support the homogeneous development of mature cartilage-like tissuesin vitrowith mechanical stiffening up to 200 kPa after 63 d. After 6 weeks ofin vivoimplantation, small-diameter microgels formed stable constructs with low immunogenicity and continuous tissue maturation. Conversely, increasing the microgel size resulted in increased inflammatory response, with limited stabilityin vivo. This study reports the development of new microgel bioinks for cartilage tissue biofabrication and offers insights into the foreign body reaction towards porous scaffolds implantation.

Lop Ear to Conchal Microtia: An Algorithmic Surgical Approach

BACKGROUND

The lop ear deformity is defined by a deficient helix and scapha, underdeveloped anthelix, and downfolding of the helix. The terminology used is still confusing, and the treatment is not entirely structured. The aim of this study was to provide a new systematic surgical approach of this deformity based on our center's experience.

MATERIALS AND METHODS

All patients undergoing surgical correction of lop ears between 2007 and 2019 at Great Ormond Street Hospital were included. Patients' data, surgical techniques, and postoperative complications were recorded.

RESULTS

Based on our records, we identified 3 surgical techniques for the correction of lop ears, based on the degree of deformity encountered. In a mild lop ear, correction was achieved with a modified otoplasty technique by improving the definition of the antihelix and superior crus. In a moderate deformity, additional remodeling of the lidded helix was performed (extended otoplasty), whereas for the severe lop ear, the amount of cupping and the deficient cartilage required formal reconstruction using a carved rib cartilage framework. There were a total of 109 patients and 146 lop ears: 58 mild, 27 moderate, and 61 severe lop ears.

CONCLUSION

We feel that there is a point in the spectrum of congenital ear deformity when a severe lop ear becomes a conchal microtia and recommend this approach to simplify the management of these cases. This is intended to bring greater clarity to how to deal with lop ears, based on the severity of the deformity and the surgical techniques used.

Management of patients with unilateral microtia and aural atresia: recent advances and updates

PURPOSE OF REVIEW

The management of patients with unilateral microtia and aural atresia is complex. Recent literature suggests significant strides in hearing habilitation and ear reconstruction.

RECENT FINDINGS

Several options of hearing management are available and are associated with improved outcomes. Timelines for hearing habilitation and ear reconstruction vary by institution. We offer our timeline as a reference. Three dimensional (3D) printed models are increasingly used for training and reconstruction. Bioprinting is on the horizon, though safety and effectiveness studies are pending. Lastly, application of qualitative methods has provided a foundation on which to improve communication between physicians and patients and their families. Better understanding of the patient and family experiences will provide opportunities to target interventions to improve care.

SUMMARY

Current developments include expanding options for hearing management, changing approaches to timing of atresiaplasty, utilization of 3D printed models, and focus on patient and family experience to improve reconstructive outcomes.

Anthropometric Study of Human Ear: A Baseline Data for Ear Reconstruction

BACKGROUND

Creation of an auricular framework plays the main role on first stage of microtia reconstruction. The size of framework is determined based on the size of the contralateral healthy ear and customized with Nagata theory. The height of rib that added behind the previous framework is the same with the projection of the normal ear. But the height of rib needed and framework in bilateral cases is unknown. A population based auricular framework pattern and projection are urgently needed.

OBJECTIVES

This study aimed at determining the mean values of normal anthropometric measurement of external ear and projection of human ear in males and females and their comparison on either sides and in either sex.

MATERIALS AND METHODS

Measurements are taken from 524 subjects (96 men and 428 women) aged 17 to 35 years using a Vernier caliper. The parameters measured were total ear height, ear width, lobular height, lobular width, upper pole, middle upper pole, middle pole, lower middle pole, lower pole, each subject's right and left ears.

RESULTS

Comparisons between gender were performed by independent t test and paired t test for comparison between right and the left ear. All dimensions were significantly different between male and female (P < 0.05) except the right lobular height (P > 0.05). There was no significant difference both side among groups (P < 0.05) except total ear height on female group (P > 0.05). All projection dimensions were significantly different between male and female. There was no significant difference of auricular projection of right and left auricular on the male (P < 0.05) groups except the projection of lower pole. There were significant between auricular projection of right and left ears on the female groups (P > 0.05).

CONCLUSIONS

These findings suggest that the normal anthropometric study will have implication in the ear reconstruction especially on bilateral cases as a baseline for reconstruction.

Tissue Engineering the Pinna: Comparison and Characterization of Human Decellularized Auricular Biological Scaffolds

Decellularization is one of the promising techniques in tissue engineering used to create a biological scaffold for subsequent repopulation with the patient's own cells. This study aims to compare two different decellularization protocols to optimize the process of auricle decellularization by assessing and characterizing the decellularization effects on human auricular cartilage. Herein, 12 pairs (8 females, 4 males) of freshly frozen adult human cadaveric auricles were de-epithelialized and defatted leaving only the cartilaginous framework. An auricle from each pair was randomly assigned to either protocol A (latrunculin B-based decellularization) or protocol B (trypsin-based decellularization). Gross examination of the generated scaffolds demonstrated preservation of the auricles' contours and a change in color from pinkish-white to yellowish-white. Hematoxylin and eosin staining demonstrated empty cartilaginous lacunae in both study groups, which confirms the depletion of cells. However, there was greater preservation of the extracellular matrix in auricles decellularized with protocol A as compared to protocol B. Comparing protocol A to protocol B, Masson's trichrome and Safranin-O stains also demonstrated noticeable preservation of collagen and proteoglycans, respectively. Additionally, scanning electron micrographs demonstrated preservation of the cartilaginous microtopography in both study groups. Biomechanical testing demonstrated a substantial decrease in Young's modulus after decellularization using protocol B (1.3 MPa), albeit not significant (P-value > 0.05) when compared to Young's modulus prior to decellularization (2.6 MPa) or after decellularization with protocol A (2.7 MPa). A DNA quantification assay demonstrated a significant drop (P-value < 0.05) in the DNA content after decellularization with protocol A (111.0 ng/mg) and protocol B (127.6 ng/mg) in comparison to before decellularization (865.3 ng/mg). Overall, this study demonstrated effective decellularization of human auricular cartilage, and it is concluded that protocol A provided greater preservation of the extracellular matrix and biomechanical characteristics. These findings warrant proceeding with the assessment of inflammation and cell migration in a decellularized scaffold using an animal model.

A Single Surgeon's Experience of Starting a New Ear Reconstruction Service in the UK

ABSTRACT

Autologous ear reconstruction is known as one of the most difficult types of reconstruction to perform in plastic surgery. Very rarely is a trainee exposed to the level of complexity and variety of cases they will treat as a sole care provider in a tertiary care setting. This is because the learning curve is steep and those few surgeons that already perform ear reconstruction are limited in what technical experience they can offer trainees due to the plethora of factors competing against the surgeon. These include patient expectations, level of experience, length of anesthetic and accountability for results and complications. For this reason, once a plastic surgeon is nominated to provide autologous ear reconstruction, they face the daunting prospect of not only performing what is a very complex surgery with a very steep learning curve but also the judgment of their patients and colleagues. This paper charts the endeavors of the senior author to provide a service over the last 5 years. It will hopefully provide insight and context on setting up a service, dealing with complications, patient and peer expectations, and finally acknowledgment from both alike as experience is gained and excellence is reached.

Vascularization of tissue engineered cartilage - Sequential in vivo MRI display functional blood circulation

Establishing functional circulation in bioengineered tissue after implantation is vital for the delivery of oxygen and nutrients to the cells. Native cartilage is avascular and thrives on diffusion, which in turn depends on proximity to circulation. Here, we investigate whether a gridded three-dimensional (3D) bioprinted construct would allow ingrowth of blood vessels and thus prove a functional concept for vascularization of bioengineered tissue. Twenty 10 × 10 × 3-mm 3Dbioprinted nanocellulose constructs containing human nasal chondrocytes or cell-free controls were subcutaneously implanted in 20 nude mice. Over the next 3 months, the mice were sequentially imaged with a 7 T small-animal MRI system, and the diffusion and perfusion parameters were analyzed. The chondrocytes survived and proliferated, and the shape of the constructs was well preserved. The diffusion coefficient was high and well preserved over time. The perfusion and diffusion patterns shown by MRI suggested that blood vessels develop over time in the 3D bioprinted constructs; the vessels were confirmed by histology and immunohistochemistry. We conclude that 3D bioprinted tissue with a gridded structure allows ingrowth of blood vessels and has the potential to be vascularized from the host. This is an essential step to take bioengineered tissue from the bench to clinical practice.

Three-Dimensional Bioprinting Scaffolding for Nasal Cartilage Defects: A Systematic Review

BACKGROUND

In recent years, three-dimensional (3D)-printing of tissue-engineered cartilaginous scaffolds is intended to close the surgical gap and provide bio-printed tissue designed to fit the specific geometric and functional requirements of each cartilage defect, avoiding donor site morbidity and offering a personalizing therapy.

METHODS

To investigate the role of 3D-bioprinting scaffolding for nasal cartilage defects repair a systematic review of the electronic databases for 3D-Bioprinting articles pertaining to nasal cartilage bio-modelling was performed. The primary focus was to investigate cellular source, type of scaffold utilization, biochemical evaluation, histological analysis, in-vitro study, in-vivo study, animal model used, length of research, and placement of experimental construct and translational investigation.

RESULTS

From 1011 publications, 16 studies were kept for analysis. About cellular sources described, most studies used primary chondrocyte cultures. The cartilage used for cell isolation was mostly nasal septum. The most common biomaterial used for scaffold creation was polycaprolactone alone or in combination. About mechanical evaluation, we found a high heterogeneity, making it difficult to extract any solid conclusion. Regarding biological and histological characteristics of each scaffold, we found that the expression of collagen type I, collagen Type II and other ECM components were the most common patterns evaluated through immunohistochemistry on in-vitro and in-vivo studies. Only two studies made an orthotopic placement of the scaffolds. However, in none of the studies analyzed, the scaffold was placed in a subperichondrial pocket to rigorously simulate the cartilage environment. In contrast, scaffolds were implanted in a subcutaneous plane in almost all of the studies included.

CONCLUSION

The role of 3D-bioprinting scaffolding for nasal cartilage defects repair is growing field. Despite the amount of information collected in the last years and the first surgical applications described recently in humans. Further investigations are needed due to the heterogeneity on mechanical evaluation parameters, the high level of heterotopic scaffold implantation and the need for quantitative histological data.

Long-term in vivo integrity and safety of 3D-bioprinted cartilaginous constructs

Long-term stability and biological safety are crucial for translation of 3D-bioprinting technology into clinical applications. Here, we addressed the long-term safety and stability issues associated with 3D-bioprinted constructs comprising a cellulose scaffold and human cells (chondrocytes and stem cells) over a period of 10 months in nude mice. Our findings showed that increasing unconfined compression strength over time significantly improved the mechanical stability of the cell-containing constructs relative to cell-free scaffolds. Additionally, the cell-free constructs exhibited a mean compressive stress and stiffness (compressive modulus) of 0.04 ± 0.05 MPa and 0.14 ± 0.18 MPa, respectively, whereas these values for the cell-containing constructs were 0.11 ± 0.08 MPa (p = .019) and 0.53 ± 0.59 MPa (p = .012), respectively. Moreover, histomorphologic analysis revealed that cartilage formed from the cell-containing constructs harbored an abundance of proliferating chondrocytes in clusters, and after 10 months, resembled native cartilage. Furthermore, extension of the experiment over the complete lifecycle of the animal model revealed no signs of ossification, fibrosis, necrosis, or implant-related tumor development in the 3D-bioprinted constructs. These findings confirm the in vivo biological safety and mechanical stability of 3D-bioprinted cartilaginous tissues and support their potential translation into clinical applications.

Posterior auricular artery free flap reconstruction of the retroauricular sulcus in microtia repair

BACKGROUND

Autologous repair using costal cartilage grafts remains the most widely accepted method of microtia reconstruction. A major complication of current techniques is loss of ear shape caused by scarring, contracture and cartilage absorption. We present a new surgical technique utilizing the posterior auricular artery free flap in microsurgical reconstruction of the retroauricular sulcus in microtia.

METHOD

Reconstruction is performed in two stages. In the first stage, a fabricated costal cartilage framework is inserted into a skin pocket as described by Nagata. In the second stage, the ear framework is elevated from the scalp and held by an additional cartilage wedge. Following indocyanine green angiography perforator mapping, a posterior auricular artery perforator flap is harvested from the contralateral (normal) ear and used to reconstruct the posterior auricular sulcus covering the cartilage framework and elevating wedge.

RESULTS

The technique was applied to three patients aged 11-15 years with a follow-up time of 8 months to 3 years. The average flap artery diameter was 0.73 mm and the vein was 0.7 mm. Venous congestion occurred in one case and was resolved with a vein graft leading to complete flap recovery. Good ear shape, elevation, projection, skin color and texture were achieved in all the cases.

CONCLUSION

Posterior auricular artery flap reconstruction of the retroauricular sulcus in microtia repair is a useful alternative to the current skin graft and tissue expander-based techniques. It provides the ideal skin color and texture match and may improve the overall results of microtia reconstruction by enhancing vascularity.

Modification of the cartilaginous framework for autologous ear reconstruction: Construction of a stable complete ring framework with grander highs and lows

BACKGROUND

Successful microtia reconstruction involves fabrication of a framework with well-defined ear subunits. Tragal definition and deep conchal bowl are key elements to produce a natural well-defined and contoured ear. We describe a modification in the cartilage framework with the purpose of increasing framework stability, tragal definition and conchal bowl depth.

METHODS

The tragus is placed on two cartilaginous bars (L-shaped), which are fixed to the framework base block creating a complete ring. These increase tragal projection and conchal depth. The tragus is carved angled posteriorly to have a shadowing effect on the absent auditory canal. Aesthetic outcome was assessed, at least 6 months after the second stage, on a 5-point ordinal scale (1-5) using the scoring system published in the UK microtia care standards and agreed on by the International Society for Auricular Reconstruction (ISAR).

RESULTS

A total of 406 auricular reconstructions were performed in 363 patients (206 right, 114 left, 43 bilateral). After excluding cases who did not have second stage and those without complete photographs, 290 cases were assessed. The described modification in the framework carving was performed in 255 ears out of these 290 ears. The mean aesthetic score before and after the modification was 2.4 and 3.09 respectively for the tragus (p < 0.001), 2.2 and 2.95 for the intertragal notch (p < 0.001) and 2.77 and 3.49 for the concha (p < 0.001).

CONCLUSIONS

This technical refinement has resulted in increased permanence and definition of the tragus and deeper and more aesthetic concha.

Clinical Results of Ear Elevations in Patients with Microtia Using Skin Grafts from Three Donor Sites: A Retrospective Study

BACKGROUND

Skin grafts, frequently used for ear elevation in ear reconstructions, may suffer from color mismatches, scar hypertrophy, secondary contraction, and auricular sulcus depth differences. To determine the most suitable donor area, we compared the contralateral postauricular area, groin, and scalp as potential donor sites.

METHODS

Since 2008, we have used three donor sites for obtaining skin grafts used in ear reconstructions. Full-thickness groin skin, split-thickness grafts from the scalp, and contralateral postauricular and groin composite full-thickness skin grafts were used in 202, 231, and 195 patients, respectively. Photographic assessments were used to assess color matching, sulcus depth, cranioauricular angle symmetry, and flatness of the skin grafts; surgical complications were also documented.

RESULTS

Among the three donor sites, there were no significant differences in the color matching scores (p = 0.456). The scalp donor scores had significantly lower mean scores for sulcus depth and symmetry and for graft flatness scores than the other donor sites. The assessment scores between the groin and postauricular donor groups were similar. Each donor site was associated with some surgical complications. However, postauricular skin, when combined with groin skin, demonstrated the best cosmetic results and the fewest complications.

CONCLUSION

All three donor sites are viable options for skin graft donor sites in ear elevation surgeries. Although the advantages and disadvantages of each site should be explained to the patient, the ultimate donor site selection may be determined according to patient and surgeon preferences.

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 .

Using 3D Printing Technology to Teach Cartilage Framework Carving for Ear Reconstruction

Objective: The aim of this study was to determine the validity of using a carvable 3D printed rib model in combination with a 3D printed auricular framework to facilitate the teaching, training and planning of auricular reconstruction. Design: 3D printed costal cartilages from ribs 6-9 were produced using a FormLabs Form3 Printer and used to make negative molds. 2:1 silicone-cornstarch mixture was added to each mold to make 12 simulated 6-9th costal cartilages suitable for carving. 3D printed auricular frameworks were produced in polylactic acid using an Ultimaker 3 3D printer to demonstrate the component parts and constructed framework of an auricular reconstruction. Participants: Twelve plastic surgery trainees attended a workshop in which they each attempted auricular reconstruction using the carvable models and 3D printed plastic models as a guide. All candidates completed a pre- and post-training questionnaire to assess confidence and comprehension of auricular reconstruction, and the suitability of the models for facilitating this teaching. Results: Only 42% of trainees (n = 5) had observed an ear reconstruction in theater prior to the training course. Statistically significant improvements in the appreciation of the different components that make an auricular framework (p < 0.0001) and confidence in carving and handling costal cartilage (p < 0.0001) were noted following completion of the training. Highly significant improvements in comprehension of the approach to ear reconstruction (p = 0.006) and locating the subunits of a reconstructed ear from costal cartilage (p = 0.003) were also noted. 100% of participants felt the 3D printed teaching aids directly enhanced their learning. Conclusions: Ear reconstruction is a complex, time consuming multi-stage operation demanding significant amounts of experience, planning and an appreciation of the 3D chondrocutaneous structure. In this study we have demonstrated the value of 3D printing in producing a suitable simulated costal cartilage model and as an adjunct to comprehending and planning a framework for auricular reconstruction.

Trends in Scientific Reports on Cartilage Bioprinting: Scoping Review

Background

Satisfactory therapeutic strategies for cartilaginous lesion repair do not yet exist. This creates a challenge for surgeons and biomedical engineers and leads them to investigate the role of bioprinting and tissue engineering as viable treatments through orthopedic surgery, plastic surgery, and otorhinolaryngology. Recent increases in related scientific literature suggest that bioprinted cartilage may develop into a viable solution.

Objective

The objectives of this review were to (1) synthesize the scientific advances published to date, (2) identify unresolved technical problems regarding human application, and (3) identify more effective ways for the scientific community to transfer their findings to clinicians.

Methods

This scoping review considered articles published between 2009 and 2019 that were identified through searching PubMed, Scopus, Web of Science, and Google Scholar. Arksey and O'Malley’s five-step framework was used to delimit and direct the initial search results, from which we established the following research questions: (1) What do authors of current research say about human application? (2) What necessary technical improvements are identified in the research? (3) On which issues do the authors agree? and (4) What future research priorities emerge in the studies? We used the Cohen kappa statistic to validate the interrater reliability.

Results

The 13 articles included in the review demonstrated the feasibility of cartilage bioprinting in live animal studies. Some investigators are already considering short-term human experimentation, although technical limitations still need to be resolved. Both the use and manufacturing process of stem cells need to be standardized, and a consensus is needed regarding the composition of hydrogels. Using on-site printing strategies and predesigned implants may allow techniques to adapt to multiple situations. In addition, the predictive capacity of implant behavior may lead to optimal results.

Conclusions

Cartilage bioprinting for surgical applications is nearing its initial use in humans. Current research suggests that surgeons will soon be able to replace damaged tissue with bioprinted material.

Decellularization of the Porcine Ear Generates a Biocompatible, Nonimmunogenic Extracellular Matrix Platform for Face Subunit Bioengineering

OBJECTIVE

The purpose of this study was to assess whether perfusion-decellularization technology could be applied to facial grafts.

BACKGROUND

Facial allotransplantation remains an experimental procedure. Regenerative medicine techniques allow fabrication of transplantable organs from an individual's own cells, which are seeded into extracellular matrix (ECM) scaffolds from animal or human organs. Therefore, we hypothesized that ECM scaffolds also can be created from facial subunits. We explored the use of the porcine ear as a clinically relevant face subunit model to develop regenerative medicine-related platforms for facial bioengineering.

METHODS

Porcine ear grafts were decellularized and histologic, immunologic, and cell culture studies done to determine whether scaffolds retained their 3D framework and molecular content; were biocompatible in vitro and in vivo, and triggered an anti-MHC immune response from the host.

RESULTS

The cellular compartment of the porcine ear was completely removed except for a few cartilaginous cells, leaving behind an acellular ECM scaffold; this scaffold retained its complex 3D architecture and biochemical components. The framework of the vascular tree was intact at all hierarchical levels and sustained a physiologically relevant blood pressure when implanted in vivo. Scaffolds were biocompatible in vitro and in vivo, and elicited no MHC immune response from the host. Cells from different types remained viable and could even differentiate at the scale of a whole-ear scaffold.

CONCLUSIONS

Acellular scaffolds were produced from the porcine ear, and may be a valuable platform to treat facial deformities using regenerative medicine approaches.

Recommendations for the Development and Reform of Microtia and Atresia Services

BACKGROUND

The initial step in setting up standardized microtia-atresia service is investigating the current status of the service and comparing this to internationally recognized guidelines or care standards. In many countries, documented information about microtia care is lacking. This study is an initiative to guide reform efforts of national microtia service in any country. The UK care standards for microtia-atresia can be a useful model to help set up a comprehensive microtia-atresia service.

METHODS

The authors conducted a survey to investigate different aspects of microtia service in Egypt. The major plastic surgery centers (n = 22) were surveyed by a structured questionnaire. The results were compared with the UK care standards for microtia-atresia to identify the aspects that need improvement. Thorough analysis of the main problems in microtia-atresia service is presented.

RESULTS

The authors found that microtia service is fragmented between the surveyed centers with 65% of the centers treating less than 10 microtia cases annually. Multiple surgeons are responsible for ear reconstruction in 90% of centers and only 25% of them practise a multidisciplinary team approach. None of the centers uses validated tools of aesthetic or psychological patient-reported outcome measures.

RECOMMENDATIONS

These 5 recommendations are the keys to reforming microtia service in any country:(1) Establishing nationally designated centers to concentrate the required expertise.(2) Assigning fewer high-volume surgeons to optimize the surgical outcomes.(3) Providing treatment by experienced multidisciplinary teams.(4) Using validated tools of patient-reported outcome measures.(5) Collecting and keeping standardized records for regular audit and intercenter studies.

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.

Autologous Ear Reconstruction for Microtia Does Not Result in Loss of Cutaneous Sensitivity

BACKGROUND

Cutaneous sensitivity of microtia reconstruction has been sparsely documented. The purpose of this study was to evaluate whether there is a loss of cutaneous sensitivity following two-stage autologous ear reconstruction for unilateral microtia.

METHODS

A prospective study was performed including unilateral microtia patients who underwent two-stage autologous ear reconstruction performed by a single plastic surgeon between 2011 and 2016. Standardized sensory testing (i.e., temperature discrimination and Semmes-Weinstein monofilaments) was executed at 11 predefined anatomical points of the affected and unaffected ears preoperatively and at 6 and 12 months postoperatively.

RESULTS

Thirty-eight patients were included. Affected and unaffected sides presented similar (all p > 0.05) preoperative cutaneous sensitivity. Most (72.7 percent) of the tested points showed (all p < 0.05) preservation or recovery of cutaneous sensitivity at 12 months postoperatively. When comparing the reconstructed ears with the unaffected ears, there was no significant difference (all p > 0.05) in most (72.7 percent) of the tested points, except (all p < 0.05) at those points involving the postauricular sulcus.

CONCLUSION

There is a temporary cutaneous sensitivity loss after a two-stage autologous microtia reconstruction, which returned to similar preoperative sensitivity at 12-month follow-up, except in the postauricular sulcus.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

A Biographical Journey Through the History of Ear Reconstruction

This historical literature review of ear reconstruction differs from much of the published literature in that it focuses on the biographies of the innovators and evangelists of ear reconstruction rather than specific techniques. A biographical account of ear reconstruction demonstrates the importance of surgeons as artists, scientists, technicians, politicians, and most importantly carers of this special and fascinating group of patients who benefit from this technically challenging form of reconstruction.

Autologous cartilage microtia reconstruction: Complications and risk factors

BACKGROUND

The Brent or Nagata techniques of microtia reconstruction and their modifications involve complicated frameworks; therefore, complications are inevitable. The authors aimed to provide comprehensive knowledge regarding the occurrence, development, prognosis, risk factors, and treatment of complications.

METHODS

This study was a retrospective review of patients who underwent autologous cartilage microtia reconstruction at a single auricular plastic and reconstructive center between March 2005 and June 2016. Custom database software was used to process data from patients with microtia. Details of postoperative complications were collected during follow-up for analysis.

RESULTS

A total of 470 procedures (stage I) were performed on 429 patients. The mean (±SD) age at surgery was 12.27 ± 5.01 years (range, 6-32 years). The mean time to follow-up was 3.67 ± 2.45 years (range, 1-11 years). The complication rate was 2.98% (4/134) with the Brent technique and 12.2% (38/311) with the Nagata technique. A multivariate logistic regression analysis of complications of microtia reconstruction revealed that age, sex, and laterality were not associated with postoperative complications (p > 0.05). Surgical technique affected the incidence of complications. The Nagata technique resulted in a higher risk for complications (OR 6.14 [95% CI 1.63-23.19]; p < 0.01).

CONCLUSION

The development of complications was a dynamic process. There was a learning curve associated with autologous cartilage microtia reconstruction. Orthopedists or otologists aspiring to master microtia reconstruction should have a fundamental understanding of the procedure and be aware of possible complications.

Surgical-Based Classification for Microtia

The known classifications for microtia have been cumbersome and difficult to apply in daily consultation. The lack of a progressive surgical behavior according to each degree of affection also contributes to confusion and in a lower success rate in clinical application. The authors propose a progressive surgical classification that takes into consideration the principal anatomical defect and the corresponding correction with modern techniques, having eliminated from previous classifications, those elements that are now considered deformations of the ear, capable of conservative treatment in early stages of life.

Microtia and Related Facial Anomalies

Infants may be born with external ear deformities or malformations that can present a diagnostic clue to an affiliated syndrome while also presenting the possibility of surgical intervention. Microtia is a malformation of the ear that is associated with other craniofacial or systemic anomalies in 50% of cases. Surgical correction of microtia and associated facial anomalies is complex and must be integrated thoughtfully into the overall care plan for children with complex medical needs. Familiarity with types of ear and facial anomalies and their association with more global concerns can allow perinatal practitioners to better serve their patients.

Skin Grafting on 3D Bioprinted Cartilage Constructs In Vivo

Background:

Three-dimensional (3D) bioprinting of cartilage is a promising new technique. To produce, for example, an auricle with good shape, the printed cartilage needs to be covered with skin that can grow on the surface of the construct. Our primary question was to analyze if an integrated 3D bioprinted cartilage structure is a tissue that can serve as a bed for a full-thickness skin graft.

Methods:

3D bioprinted constructs (10 × 10 × 1.2 mm) were printed using nanofibrillated cellulose/alginate bioink mixed with mesenchymal stem cells and adult chondrocytes and implanted subcutaneously in 21 nude mice.

Results:

After 45 days, a full-thickness skin allograft was transplanted onto the constructs and the grafted construct again enclosed subcutaneously. Group 1 was sacrificed on day 60, whereas group 2, instead, had their skin-bearing construct uncovered on day 60 and were sacrificed on day 75 and the explants were analyzed morphologically. The skin transplants integrated well with the 3D bioprinted constructs. A tight connection between the fibrous, vascularized capsule surrounding the 3D bioprinted constructs and the skin graft were observed. The skin grafts survived the uncovering and exposure to the environment.

Conclusions:

A 3D bioprinted cartilage that has been allowed to integrate in vivo is a sufficient base for a full-thickness skin graft. This finding accentuates the clinical potential of 3D bioprinting for reconstructive purposes.

Auricular reconstruction of congenital microtia by using the modified Nagata method: Personal 10-Year experience with 1350 cases

BACKGROUND

Total auricular reconstruction is currently one of the most challenging plastic surgery procedures. Herein, we present our 10-year experience with 1350 cases of ear reconstruction by using Nagata method with necessary improvement.

METHODS

Factors related to ear reconstruction, namely, remnant ear, mastoid skin, adjacent scalp, rib cartilages, normal ear, and mastoid process, were carefully evaluated before operation. An individualized design and precise framework fabrication were performed for each patient. Necessary modifications in fabricating base frame, helix, tragus, and antihelix were introduced to achieve a stable and individualized framework. These efforts also reduced the quantity of cartilage required for ear reconstruction.

RESULTS

Follow-up time ranged from 1 month to 5 years, and 1217 (90.1%) patients were satisfied with the reconstructed ears, which showed appropriate color, texture, size, and location. The modifications made conferred a harmonious and individualized contour of the reconstructed ears. Incidence of all complications such as hematoma, skin necrosis, and framework absorption was very low.

CONCLUSIONS

Based on preoperative assessment, individualized design, and precise sculpting, a harmonious and individual auricle with detailed anatomical structures was achieved by using our modified Nagata method in which a stable and sophisticated framework can be fabricated with less cartilage requirement.

Perfusion-decellularization of human ear grafts enables ECM-based scaffolds for auricular vascularized composite tissue engineering

INTRODUCTION

Human ear reconstruction is recognized as the emblematic enterprise in tissue engineering. Up to now, it has failed to reach human applications requiring appropriate tissue complexity along with an accessible vascular tree. We hereby propose a new method to process human auricles in order to provide a poorly immunogenic, complex and vascularized ear graft scaffold.

METHODS

12 human ears with their vascular pedicles were procured. Perfusion-decellularization was applied using a SDS/polar solvent protocol. Cell and antigen removal was examined by histology and DNA was quantified. Preservation of the extracellular matrix (ECM) was assessed by conventional and 3D-histology, proteins and cytokines quantifications. Biocompatibility was assessed by implantation in rats for up to 60 days. Adipose-derived stem cells seeding was conducted on scaffold samples and with human aortic endothelial cells whole graft seeding in a perfusion-bioreactor.

RESULTS

Histology confirmed cell and antigen clearance. DNA reduction was 97.3%. ECM structure and composition were preserved. Implanted scaffolds were tolerated in vivo, with acceptable inflammation, remodeling, and anti-donor antibody formation. Seeding experiments demonstrated cell engraftment and viability.

CONCLUSIONS

Vascularized and complex auricular scaffolds can be obtained from human source to provide a platform for further functional auricular tissue engineered constructs, hence providing an ideal road to the vascularized composite tissue engineering approach.

STATEMENT OF SIGNIFICANCE

The ear is emblematic in the biofabrication of tissues and organs. Current regenerative medicine strategies, with matrix from donor tissues or 3D-printed, didn't reach any application for reconstruction, because critically missing a vascular tree for perfusion and transplantation. We previously described the production of vascularized and cell-compatible scaffolds, from porcine ear grafts. In this study, we ---- applied findings directly to human auricles harvested from postmortem donors, providing a perfusable matrix that retains the ear's original complexity and hosts new viable cells after seeding. This approach unlocks the ability to achieve an auricular tissue engineering approach, associated with possible clinical translation.

Splinting After Ear Reconstruction: A Stepwise and Inexpensive Workflow Protocol

BACKGROUND

Long-term postoperative splinting plays a role in the prevention of contracture of the grafted skin after a second-stage ear reconstruction. The scar retraction could lead to an unfavorable aesthetic outcome. Splinting could play a role to overcome or prevent the loss of projection and the obliteration of the sulcus.

MATERIAL AND METHODS

We have defined the characteristics of an ideal long-term splint and present a stepwise clinical protocol for the fabrication of an ethylene-vinyl acetate splint. The splint was applied to all patients included in a prospective study on the postoperative splinting regime. Ethylene-vinyl acetate has proved its safety and longevity in dental prosthetics.

CONCLUSIONS

Patient compliance was optimal, and no allergic reactions, pressure sores, or skin necrosis were reported. The splint is self-retaining and light weight. Because of its transparent color, it can be easily camouflaged. A stepwise clinical protocol for the fabrication of a low-cost patient-specific ear splint is presented.

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.

Chondrocytes and stem cells in 3D-bioprinted structures create human cartilage in vivo

Cartilage repair and replacement is a major challenge in plastic reconstructive surgery. The development of a process capable of creating a patient-specific cartilage framework would be a major breakthrough. Here, we described methods for creating human cartilage in vivo and quantitatively assessing the proliferative capacity and cartilage-formation ability in mono- and co-cultures of human chondrocytes and human mesenchymal stem cells in a three-dimensional (3D)-bioprinted hydrogel scaffold. The 3D-bioprinted constructs (5 × 5 × 1.2 mm) were produced using nanofibrillated cellulose and alginate in combination with human chondrocytes and human mesenchymal stem cells using a 3D-extrusion bioprinter. Immediately following bioprinting, the constructs were implanted subcutaneously on the back of 48 nude mice and explanted after 30 and 60 days, respectively, for morphological and immunohistochemical examination. During explantation, the constructs were easy to handle, and the majority had retained their macroscopic grid appearance. Constructs consisting of human nasal chondrocytes showed good proliferation ability, with 17.2% of the surface areas covered with proliferating chondrocytes after 60 days. In constructs comprising a mixture of chondrocytes and stem cells, an additional proliferative effect was observed involving chondrocyte production of glycosaminoglycans and type 2 collagen. This clinically highly relevant study revealed 3D bioprinting as a promising technology for the creation of human cartilage.

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.

[Reconstructive otoplasty: differentiated approach to rib cartilage processing and ear framework formation using carving technique]

The aim of the research was to optimize surgical rehabilitation of patients with auricle defects and deformities by the developing of differentiated approach to the choice of reconstructive otoplasty method. The study involved 30 patients with auricle defects and deformities of congenital (20 patients) and acquired (10 patients) etiology. The defects were total in 25 patients and partial in 5 patients. All patients underwent ear reconstruction with rib cartilage using carving technique. Preoperative planning was based in Doppler ultrasound of temporal region vessels, laser Doppler flowmetry, temporal skin ultrasound and 3D ribcage CT. The surgical tactic was selected according to the possibility of mastoid region skin usage or necessity of the temporoparietal fascial flap. The approach proved to be highly efficient as otoplasty outcomes were good in 80% of cases, satisfactory in 10% and unsatisfactory in 10%.

Microtia Reconstruction

Microtia reconstruction is a challenging endeavor that has seen significant technique evolution. It is important to educate patients and their families to determine the best hearing rehabilitation and ear reconstructive options. Microtia is often associated with aural atresia, hearing loss, and craniofacial syndromes. Optimal care is provided by multiple disciplines, including a reconstructive surgeon, an otologic surgeon, an audiologist, and a craniofacial pediatrician. Microtia management includes observation, prosthetic ear, autologous cartilage reconstruction, or alloplastic implant placement. Hearing management options are observation, bone conduction sound processor, or atresiaplasty with and without hearing aids. Appropriate counseling should be done to manage expectations.

Computer-Aided Design and 3-Dimensional Printing for Costal Cartilage Simulation of Airway Graft Carving

Autologous cartilage grafting during open airway reconstruction is a complex skill instrumental to the success of the operation. Most trainees lack adequate opportunities to develop proficiency in this skill. We hypothesized that 3-dimensional (3D) printing and computer-aided design can be used to create a high-fidelity simulator for developing skills carving costal cartilage grafts for airway reconstruction. The rapid manufacturing and low cost of the simulator allow deployment in locations lacking expert instructors or cadaveric dissection, such as medical missions and Third World countries. In this blinded, prospective observational study, resident trainees completed a physical simulator exercise using a 3D-printed costal cartilage grafting tool. Participant assessment was performed using a Likert scale questionnaire, and airway grafts were assessed by a blinded expert surgeon. Most participants found this to be a very relevant training tool and highly rated the level of realism of the simulation tool.

In Vivo Chondrogenesis in 3D Bioprinted Human Cell-laden Hydrogel Constructs

BACKGROUND

The three-dimensional (3D) bioprinting technology allows creation of 3D constructs in a layer-by-layer fashion utilizing biologically relevant materials such as biopolymers and cells. The aim of this study is to investigate the use of 3D bioprinting in a clinically relevant setting to evaluate the potential of this technique for in vivo chondrogenesis.

METHODS

Thirty-six nude mice (Balb-C, female) received a 5- × 5- × 1-mm piece of bioprinted cell-laden nanofibrillated cellulose/alginate construct in a subcutaneous pocket. Four groups of printed constructs were used: (1) human (male) nasal chondrocytes (hNCs), (2) human (female) bone marrow-derived mesenchymal stem cells (hBMSCs), (3) coculture of hNCs and hBMSCs in a 20/80 ratio, and (4) Cell-free scaffolds (blank). After 14, 30, and 60 days, the scaffolds were harvested for histological, immunohistochemical, and mechanical analysis.

RESULTS

The constructs had good mechanical properties and keep their structural integrity after 60 days of implantation. For both the hNC constructs and the cocultured constructs, a gradual increase of glycosaminoglycan production and hNC proliferation was observed. However, the cocultured group showed a more pronounced cell proliferation and enhanced deposition of human collagen II demonstrated by immunohistochemical analysis.

CONCLUSIONS

In vivo chondrogenesis in a 3D bioprinted human cell-laden hydrogel construct has been demonstrated. The trophic role of the hBMSCs in stimulating hNC proliferation and matrix deposition in the coculture group suggests the potential of 3D bioprinting of human cartilage for future application in reconstructive surgery.

An Alternative Posterosuperior Auricular Fascia Flap for Ear Elevation During Microtia Reconstruction

BACKGROUND

Advances in staged total auricular reconstruction have resulted in improved anterior auricular appearance; however, satisfactory postreconstruction esthetics of the retroauricular fold remain challenging. The postauricular appearance of the reconstructed ear depends largely upon optimizing the covering material. When used as the covering soft tissue for ear elevation, a flap containing primarily the upper portion of the retroauricular fascia has potential advantages over the conventional book cover-type retroauricular fascia flap.

METHODS

We developed a geometrically designed, posterosuperior auricular fascia flap to replace the conventional retroauricular fascia flap for ear elevation. During the second-stage operation, the posterosuperior auricular fascia flap is rotated downward and turned over to wrap around the inner strut and entire posterior auricular surface.

RESULTS

Compared to the conventional book cover-type retroauricular fascia flap, the novel posterosuperior auricular fascia flap was easier to harvest and the operative time significantly decreased (110.3 vs. 121.5 min, p < 0.01). The modified flap produced a thin and natural contour of the postauricular surface, as well as reduced the incidence of postauricular hypertrophic scarring (from 24.7 to 13.2%, p = 0.03) and partial skin graft necrosis (from 43.4 to 31.2%, p = 0.01).

CONCLUSION

The geometrically designed posterosuperior auricular fascia flap improves ear elevation. Compared to the conventional book cover-type retroauricular fascia flap, this covering tissue is easier to perform so the surgical time is decreased. It was highly vascularized, well defined, thinner, and yields reliable results. Thus, favorable postauricular surface results can be achieved during auricular reconstruction by using the modified fascia flap.

NO LEVEL ASSIGNED

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