Lower eyelid retraction repair using autologous auricular scapha cartilage.

PURPOSE: To assess the efficacy of lower eyelid retraction surgery utilizing autologous auricular scapha cartilage (located within the anterior surface groove between the helix and anti-helix) and to present the surgical outcomes in a patient cohort. METHODS: Medical records of 21 patients who underwent lower eyelid retraction surgery with scapha cartilage were retrospectively reviewed. Retractions, present for an extended duration (6 months to 20 years), exhibited 1 mm or more inferior scleral show, attributed to prior lower eyelid blepharoplasty, facial palsy, or as a normal anatomical variation. Surgical interventions included lateral canthotomy, cantholysis, incision of the subtarsal conjunctiva-lower eyelid retractors, lower eyelid retractor lysis, cartilage graft suturing to the defect area without conjunctival cover, and tightening of the lateral canthal corner in all patients. RESULTS: A total of 29 eyelids in 21 patients underwent surgery without intraoperative complications. Over a mean follow-up period of 11 months (range: 6-30 months), lower lid retraction improved in 96.5% of eyelids. Postoperative margin-to-reflex distance measurements (MRD2) significantly decreased compared to preoperative values (p = 0.001; p < 0.01). Average improvements in MRD2-a (midpupil to lower lid) and MRD2-b (lateral limbus to lower lid) were 1.77 ± 0.80 and 2.04 ± 0.81, respectively (p = 0.001; p < 0.01). Four eyelids (4/29) required revision due to canthal corner loosening, with correction necessitating periosteal flaps. All four patients had previously undergone two or more repairs elsewhere. The graft was visible in two lids but did not require further revision. One patient experienced mild helix deformity at the donor site, which did not warrant additional intervention. CONCLUSION: In cases of lower lid retraction associated with middle/posterior lamellar shortening, utilizing an autologous auricular scapha cartilage spacer graft offers notable benefits. These advantages comprise straightforward harvesting with minimal donor site complications, stability without experiencing shrinkage, a softer texture in comparison to posterior cartilage, a concave shape that facilitates proper fitting on the globe, and its autologous nature.

Accessory tympanic plate ossicle: a new osteological entity.

The auricular cartilage, which is typically soft and flexible, can calcify or ossify because of diseases such as diabetes mellitus, trauma, radiation therapy for cancer, and more commonly from frostbite. Calcified, ossified, or hardened auricular cartilage is a rare finding in the clinical literature and appears to be absent in the physical and forensic anthropological literature. This study examines the ossified auricular cartilage and tests whether the hypothesis can be identified in postmortem skeletonized tissue and be part of the external auditory meatus. A total of 290 crania were examined for accessory ossicles. A descriptive and interpretative analysis was performed grossly, histologically, and morphometrically to document the morphology and location of the ossicles, investigate their structure, and perform hypothesis testing. Results revealed that seven females and one male crania from a total of 290 crania (2.76%) exhibit semi-ossified auricular cartilage attached to the tympanic plate of the temporal bone. The morphology and location of the ossicles at the junction of the auricle and external auditory meatus indicate they are hardened auricular cartilage that was verified with histological observations. Regression analysis indicates that addition of the ossicle to the depth of the auditory tube significantly changes coefficient of determination (R2) with respect to cranial breadth. In conclusion, results indicate that small cartilaginous structures of the external ear may ossify forming accessory tympanic plate ossicles that potentially could be identified in skeletal remains as a new osteological entity. This report highlights the types of information that can be gained using an approach that integrates forensic anthropology, gross anatomy, and histology.

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

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

Histological assessment of microtia cartilage, a potential source of autograft tissue in ear reconstruction.

Cartilage is a strong and flexible connective tissue that has many forms and functions in our body. While cartilage exhibits some forms of limited repair, for the most part, it is not particularly regenerative. Thus, in situations where patients require cartilage reconstruction, surgeons may use autografts to replace missing or damaged tissue. Cartilage tissues from different regions of the body exhibit histological differences and are in limited supply. Thus, it is important to characterize these differences to determine the most appropriate autograft source. In the case of microtia, a congenital deformity where the pinna is underdeveloped, reconstruction commonly utilizes cartilage sourced from a patient's own costal cartilage. This presents a potential morbidity risk. In this study, we evaluate the histological characteristics of microtia cartilage compared with normal auricular and costal cartilage obtained from human patients undergoing surgical resection. Histochemistry was used to evaluate cellularity, lipid content, and ECM content. Using a Bayesian statistical approach, we determined that while costal cartilage is the standard tissue donor, the microanatomy of microtia cartilage more closely reflects normal auricular cartilage than costal cartilage. Therefore, microtia cartilage may serve as an additional reservoir for cartilage during reconstruction.

Investigation of Two New Grafting Techniques for Dorsal Augmentation Rhinoplasty: An Experimental Study with New Zealand White Rabbits.

INTRODUCTION: Cartilage is an important source in supporting the structure of the nose for dorsal augmentation rhinoplasty. However, it is known that its viability is not always on the ideal level. Various wrapping materials are used to increase the strength of cartilage. Donor site morbidity, which develops following the harvesting of both cartilage and fascia as one such cover material, has attracted interest in recent years. OBJECTIVE: In this study, we aimed to investigate the potential of dermis and tendon autografts as alternatives to fascia and cartilage. MATERIAL AND METHOD: The sample of the study included 16 New Zealand white rabbits. The right auricular cartilage of all rabbits was amputated, and it was transformed into diced cartilage autografts. The dermis autografts from the right gluteal areas of the rabbits were deepithelialized, and lumbosacral fascia autografts were harvested from the same incision. Additionally, the Achilles tendon of each rabbit was harvested and transformed into diced tendon autografts. Four different autografts were embedded under the skin of each rabbit from 4 different pouches opened in the back of the rabbit. These autografts included diced cartilage alone (Intervention 1), fascia-wrapped cartilage (Intervention 2), dermis-wrapped cartilage (Intervention 3) and fascia-wrapped tendon (Intervention 4) autografts. RESULTS: Intervention 1 had the most irregular appearance, the outcomes in Intervention 4 were volumetrically smaller and softer. Connective tissue formed between the diced pieces in all interventions, and it was observed that the dermis and fascia had a capsule-like appearance, and their viability was preserved. The differences between the initial and final measurements of the volumes of interventions 1, 2 and 3 were statistically significant (p < 0.05). There was no significant difference between the initial and final volumetric measurements of intervention 4 (p > 0.05). More peripheral proliferation was observed in the interventions of fascia-wrapped and dermis-wrapped diced cartilage compared to the other interventions. The intervention including fascia-wrapped diced tendon grafts had displayed more fibrosis, fragmentation and collagen fibers, while it showed a lower amount of elastic fiber. There were no significant differences among the intervention in terms of other histological parameters. CONCLUSION: Tendon autografts may be a good option for dorsal augmentation rhinoplasty as they are easily harvested and have minimal donor site morbidity. Dermis autograft usage is more advantageous than fascia usage in terms of accessibility and convenience. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies and Experimental Studies. 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 .

Low-Temperature Extrusion of Waterborne Polyurethane-Polycaprolactone Composites for Multi-Material Bioprinting of Engineered Elastic Cartilage.

3D bioprinting of elastic cartilage tissues that are mechanically and structurally comparable to their native counterparts, while exhibiting favorable cellular behavior, is an unmet challenge. A practical solution for this problem is the multi-material bioprinting of thermoplastic polymers and cell-laden hydrogels using multiple nozzles. However, the processing of thermoplastic polymers requires high temperatures, which can damage hydrogel-encapsulated cells. In this study, the authors developed waterborne polyurethane (WPU)-polycaprolactone (PCL) composites to allow multi-material co-printing with cell-laden gelatin methacryloyl (GelMA) hydrogels. These composites can be extruded at low temperatures (50-60 °C) and high speeds, thereby reducing heat/shear damage to the printed hydrogel-capsulated cells. Furthermore, their hydrophilic nature improved the cell behavior in vitro. More importantly, the bioprinted structures exhibited good stiffness and viscoelasticity compared to native elastic cartilage. In summary, this study demonstrated low-temperature multi-material bioprinting of WPU-PCL-based constructs with good mechanical properties, degradation time-frames, and cell viability, showcasing their potential in elastic cartilage bio-fabrication and regeneration to serve broad biomedical applications in the future.

Profiling of Long Non-Coding RNAs in Auricular Cartilage of Patients with Isolated Microtia.

Introduction: Microtia is the second most common maxillofacial birth defect worldwide. However, the involvement of long non-coding RNAs (lncRNAs) in isolated microtia is not well understood. This study aimed at identifying lncRNAs that regulate the expression of genes associated with isolated microtia. Methods: We used our microarray data to analyze the expression pattern of lncRNA in the auricular cartilage tissues from 10 patients diagnosed with isolated microtia, alongside 15 control subjects. Five lncRNAs were chosen for validation using real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Results: We identified 4651 differentially expressed lncRNAs in the auricular cartilage from patients with isolated microtia. By Gene Ontology/Kyoto Encyclopedia of Genes and Genomes pathway (GO/KEGG) analysis, we identified 27 differentially expressed genes enriched in pathways associated with microtia. In addition, we predicted 9 differentially expressed genes as potential cis-acting targets of 12 differentially expressed lncRNAs. Our findings by qRT-PCR demonstrate significantly elevated expression levels of ZFAS1 and DAB1-AS1, whereas ADIRF-AS1, HOTAIRM1, and EPB41L4A-AS1 exhibited significantly reduced expression levels in the auricular cartilage tissues of patients with isolated microtia. Conclusions: Our study sheds light on the potential involvement of lncRNAs in microtia and provides a basis for further investigation into their functional roles and underlying mechanisms.

Construction of Integral Decellularized Cartilage Using a Novel Hydrostatic Pressure Bioreactor.

The decellularized extracellular matrix (ECM) of cartilage is a widely used natural bioscaffold for constructing tissue-engineered cartilage due to its good biocompatibility and regeneration properties. However, current decellularization methods for accessing decellularized cartilaginous tissues require multiple steps and a relatively long duration to produce decellularized cartilage. In addition, most decellularization strategies lead to damage of the microstructure and loss of functional components of the cartilaginous matrix. In this study, a novel decellularization strategy based on a hydrostatic pressure (HP) bioreactor was introduced, which aimed to improve the efficiency of producing integral decellularized cartilage pieces by combining physical and chemical decellularization methods in a perfusing manner. Two types of cartilaginous tissues, auricular cartilage (AC) and nucleus pulposus (NP) fibrocartilage, were selected for comparison of the effects of ordinary, positive, and negative HP-based decellularization according to the cell clearance ratio, microstructural changes, ECM components, and mechanical properties. The results indicated that applying positive HP improved the efficiency of producing decellularized AC, but no significant differences in decellularization efficiency were found between the ordinary and negative HP-treated groups. However, compared with the ordinary HP treatment, the application of the positive or negative HP did not affect the efficiency of decellularized NP productions. Moreover, neither positive nor negative HP influenced the preservation of the microstructure and components of the AC matrix. However, applying negative HP disarranged the fibril distribution of the NP matrix and reduced glycosaminoglycans and collagen type II contents, two essential ECM components. In addition, the positive HP was beneficial for maintaining the mechanical properties of decellularized cartilage. The recellularization experiments also verified the good biocompatibility of the decellularized cartilage produced by the present bioreactor-based decellularization method under positive HP. Overall, applying positive HP-based decellularization resulted in a superior effect on the production of close-to-natural scaffolds for cartilage tissue engineering. Impact statement In this study, we successfully constructed a novel hydrostatic pressure (HP) bioreactor and used this equipment to produce decellularized cartilage by combining physical and chemical decellularization methods in a perfusing manner. We found that positive HP-based decellularization could improve the production efficiency of integral decellularized cartilage pieces and promote the maintenance of matrix components and mechanical properties. This new decellularization strategy exhibited a superior effect in the production of close-to-natural scaffolds and positively impacts cartilage tissue engineering.

Age-Related Histologic and Biochemical Changes in Auricular and Nasal Cartilages.

OBJECTIVE: Analyze age-related changes in histologic features and biochemical properties of human auricular cartilage and two subsites of nasal cartilages (quadrangular cartilage and dorsal septal articulation with upper lateral cartilages). STUDY DESIGN: Prospective cross-sectional study of nasal and auricular cartilages from seventy-three (73) live donors. METHODS: Auricular cartilage (AC), quadrangular cartilage (QC), and dorsal septal cartilage articulation (DSA) with the upper lateral cartilage (ULCs) were collected intraoperatively. Histochemical staining was used: Safranin O for glycosaminoglycans (GAGs), Verhoeff's for elastin, and Masson's trichrome for collagen. ImageJ2 software was used to calculate cell count and percent stained for each cartilage type. R studio "ggplot" package was used to visualize age versus cell count or percent stained. RESULTS: Participant ages ranged from 20 to 77 years, average 46.5 years. There was a significant decline in GAGs with age for the DSA subsite, (n = 64, p < 0.001). Significant increase in collagen content with age was observed for DSA subsite (n = 66, p < 0.001) and the QC subsite (n = 64, p < 0.05). There was a statistically insignificant decline in elastin with age (n = 41, p = 0.309) for AC. Cell count declined with age at all cartilage subsites. CONCLUSION: Our findings confirm that there were age-related decreases in cartilage glycosaminoglycan content, and chondrocyte cell count in both auricular and nasal cartilages. We have also confirmed that collagen content increases with age for both auricular and nasal cartilage. The histologic findings while not statistically significant in all comparisons, provides additional evidence that there is some loss of structural integrity and flexibility in nasal and auricular cartilage with aging. LEVEL OF EVIDENCE: NA Laryngoscope, 134:1220-1226, 2024.

Chondrocyte-laden gelatin/sodium alginate hydrogel integrating 3D printed PU scaffold for auricular cartilage reconstruction.

Clinically, modified autologous rib cartilage grafts and commercial implants are commonly used for intraoperative repair of auricular cartilage defects caused by injuries. However, scaffold implantation is often accompanied by various complications including absorption and collapse, resulting in undesirable clinical outcomes. Three-dimensional printed auricular cartilage scaffolds have the advantage of individual design and biofunctionality, which attracted tremendous attention in this field. In this study, to better simulate the mechanical properties of auricular cartilage, we tested PU treated by ultrasonication and high temperature for 30 min (PU-30) or 60 min (PU-60). The results indicated that the compression modulus of PU-30 was 2.21-2.48 MPa, which similar to that of natural auricular cartilage (2.22-7.23 MPa) and was chosen for subsequent experiments. And the pores of treated PU were filled with a gelatin/sodium alginate hydrogel loaded with chondrocytes. In vivo analysis using a rabbit model confirmed that implanted PU-30 scaffold filled with chondrocytes contained hydrogel successfully integrated with normal auricular cartilage, and that new cartilage was generated at the scaffold-tissue interface by histological examination. These findings illustrate that this engineered scaffold represents a potential strategy for repair of ear cartilage damage in clinical.

The application and progress of stem cells in auricular cartilage regeneration: a systematic review.

Background: The treatment of microtia or acquired ear deformities by surgery is a significant challenge for plastic and ENT surgeons; one of the most difficult points is constructing the scaffold for auricular reconstruction. As a type of cell with multiple differentiation potentials, stem cells play an essential role in the construction of cartilage scaffolds, and therefore have received widespread attention in ear reconstructive research. Methods: A literature search was conducted for peer-reviewed articles between 2005 and 2023 with the following keywords: stem cells; auricular cartilage; ear cartilage; conchal cartilage; auricular reconstruction, regeneration, and reparation of chondrocytes; tissue engineering in the following databases: PubMed, MEDLINE, Cochrane, and Ovid. Results: Thirty-three research articles were finally selected and their main characteristics were summarized. Adipose-derived stem cells (ADSCs), bone marrow mesenchymal stem cells (BMMSCs), perichondrial stem/progenitor cells (PPCs), and cartilage stem/progenitor cells (CSPCs) were mainly used in chondrocyte regeneration. Injecting the stem cells into the cartilage niche directly, co-culturing the stem cells with the auricular cartilage cells, and inducing the cells in the chondrogenic medium in vitro were the main methods that have been demonstrated in the studies. The chondrogenic ability of these cells was observed in vitro, and they also maintained good elasticity and morphology after implantation in vivo for a period of time. Conclusion: ADSC, BMMSC, PPC, and CSPC were the main stem cells that have been researched in craniofacial cartilage reconstruction, the regenerative cartilage performed highly similar to normal cartilage, and the test of AGA and type II collagen content also proved the cartilage property of the neo-cartilage. However, stem cell reconstruction of the auricle is still in the initial stage of animal experiments, transplantation with such scaffolds in large animals is still lacking, and there is still a long way to go.

Application of Auricular Cartilage-Skin Graft in the Reconstruction of Unilateral Cleft Lip Nasal Deformity.

BACKGROUND: Autologous cartilage grafts are increasingly used in the treatment of cleft lip nasal deformity, but nasal alar retraction caused by lining defects often occurs after surgery. We designed a new graft to treat unilateral cleft lip nasal deformity while avoiding nasal alar retraction. METHODS: Nineteen patients in our hospital underwent unilateral cleft lip nasal deformity repair surgery with an auricular cartilage-skin graft. The effect of surgery was evaluated in four aspects: satisfaction with postoperative appearance, nasal aesthetic subunit indices, position of the nasal alar rim and three-dimensional spatial difference. RESULTS: Overall satisfaction with each index was above 90%. The nasal tip angle and nasolabial angle of patients were significantly smaller after surgery than before surgery (P < 0.01). The height of the nostril on the affected side and the length of the nasal columella were greater after surgery than before surgery (P < 0.01). The spatial differences in soft tissue between the unaffected side and the affected side after surgery were significantly smaller than before surgery (P < 0.01). According to the follow-up results of 1-2 years, there were no significant retraction of the nasal alar rim (P > 0.05) and no obvious auricular deformity. All patients had a noticeable improvement in their nasal appearance. CONCLUSION: The auricular cartilage-skin graft, which can not only improve the appearance of the nose but also avoid nasal alar retraction, is an ideal graft to cure unilateral cleft lip nasal deformity. 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 .

A reinforced framework construction technique using unilateral auricular cartilage in Asian rhinoplasty to prevent long-term nasal tip drooping.

BACKGROUND: Enhancing nasal tip projection is an important objective in Asian rhinoplasty. Nasal tip enhancement using auricular cartilage is simple and suitable for Asian patients. However, the long-term retraction problem of the auricular framework still needs to be solved for optimal results. OBJECTIVES: The authors propose a modified auricular cartilage framework construction technique that provides stronger long-term support to the nasal tip and columellar base. METHODS: Eighty-one patients underwent augmentation rhinoplasty between January 2016 and December 2019. The cymba and cavum conchae were harvested from one ear in all cases. The cymba concha was carved and folded to form a caudal septal extension graft (CSEG). The cavum concha was divided into an integrated cap/shield graft and a columella base graft. The columella base graft was diced into particles in size of 1 mm3, and inserted into the gap between CSEG, anterior nasal spine, and the medial crus to strengthen the foundation. The nasal profile was analyzed before the operation and at least 12 months after the operation. The patient satisfaction score was assessed 12 months after surgery. RESULTS: Patients were followed up for 12-36 months. The nasal tip projection from both the lateral and basal views was significantly improved. The columella-labial angle was increased from 83.15° (6.20°) to 96.50° (7.40°) (p < 0.05). The nostril tip proportion increased from 0.83 (0.14) to 1.17(0.16) (p < 0.01). A stable long-term outcome was achieved. CONCLUSIONS: With the modified framework construction technique, long-term nasal tip drooping can be prevented. This method can be a practical choice for Asian patients seeking augmentation rhinoplasty.

A comparison of novel silicone plate vs. auricular cartilage in upper eyelid reconstruction following excision of malignant tumor.

Purpose: To compare surgical and functional outcomes, safety, efficacy and cost of silicone plate vs. autogenous auricular cartilage (AAC) as alternate material to tarsal plate for upper eyelid reconstruction after excision of malignant tumor. Methods: A prospective, comparative, interventional study of over 3 years was conducted on two groups of twenty patients each. All the patients had undergone the Modified Cutler Beard procedure with AAC being used as tarsal substitute in one group and a novel silicone plate in the other. Post-operative MRD 1, LPS action, Central Lid Thickness, and Lid contour were recorded at one week, one month and six months follow-up. Results: The pre-operative MRD 1 in the silicone plate and AAC group was -2.95 ± 1.19 mm and -3.05 ± 1(1).05 mm, post-operative in the silicone plate group 3.8 ± 0.4 mm, and in the AAC group, 3.8 ± 0.41 mm. The pre-operative LPS action in the silicone plate and AAC group was 1.2 ± 1.1 mm and 1.0 ± 0.9 mm and post-operative it was 13.8 ± 0.4 mm for the silicone plate group and 13.7 ± 0.4 mm for the AAC group. The post-operative lid thickness for the silicone plate group was 4.4 ± 0.17 mm and for the AAC group it was 4.4 ± 0.08 mm. Conclusion: The cosmetic outcome in terms of lid contour maintenance is better in the silicone plate group, in which it markedly reduces the surgical time, provides earlier rehabilitation, and eliminates disease transmission. Harvesting of AAC is a skillful and time-consuming procedure and adds to the post-operative morbidity due to the presence of a second surgical site. The low manufacturing cost of silicone plate as opposed to other allogenic and synthetic tarsal substitutes makes it readily available to resource limited populations. The silicone plate is reckoned to become the material of choice as tarsal substitute in the future. Abbreviations: AAC = Autogenous auricular cartilage, MRD-1 = Margin reflex distance-1, LPS = levator palpebrae superioris, PFH = palpebral fissure height.

Fabrication of 3D-Printed Implant for Two-Stage Ear Reconstruction Surgery and Its Clinical Application.

PURPOSE: Ear reconstruction is one of the most difficult areas in the field of reconstructive surgery. Due to limitations of the current practice, a novel method of auricular reconstruction is needed. Major advancements in three-dimensional (3D) printing technique have rendered the process of ear reconstruction more favorable. Herein, we present our experience in designing and clinically using 3D implants in both 1st and 2nd stage ear reconstruction surgery. MATERIALS AND METHODS: After obtaining 3D CT data from each patient, a 3D geometric ear model was created using mirroring and segmentation processes. The 3D-printed implant design resembles but does not exactly match the normal ear shape, and can be inserted in harmony with the currently used surgical technique. The 2nd stage implant was designed to minimize dead space and support the posterior ear helix. The 3D implants were finally fabricated with a 3D printing system and used in ear reconstruction surgery in our institute. RESULTS: The 3D implants were manufactured for application to the currently used two-stage technique while maintaining the shape of the patient's normal ear. The implants were successfully used for ear reconstruction surgery in microtia patients. A few months later, the 2nd stage implant was used in the 2nd stage operation. CONCLUSION: The authors were able to design, fabricate, and apply patient-specific 3D-printed ear implants for 1st and 2nd stage ear reconstruction surgeries. This design, combined with 3D bioprinting technique, may be a future alternative for ear reconstruction.

Bacterial nanocellulose-reinforced gelatin methacryloyl hydrogel enhances biomechanical property and glycosaminoglycan content of 3D-bioprinted cartilage.

Tissue-engineered ear cartilage scaffold based on three-dimensional (3D) bioprinting technology presents a new strategy for ear reconstruction in individuals with microtia. Natural hydrogel is a promising material due to its excellent biocompatibility and low immunogenicity. However, insufficient mechanical property required for cartilage is one of the major issues pending to be solved. In this study, the gelatin methacryloyl (GelMA) hydrogel reinforced with bacterial nanocellulose (BNC) was developed to enhance the biomechanical properties and printability of the hydrogel. The results revealed that the addition of 0.375% BNC significantly increased the mechanical properties of the hydrogel and promoted cell migration in the BNC-reinforced hydrogel. Constructs bioprinted with chondrocyte-laden BNC/GelMA hydrogel bio-ink formed mature cartilage in nude mice with higher Young's modulus and glycosaminoglycan content. Finally, an auricle equivalent with a precise shape, high mechanics, and abundant cartilage-specific matrix was developed in vivo. In this study, we developed a potentially useful hydrogel for the manufacture of auricular cartilage grafts for microtia patients.

Regeneration of Rabbit Auricular Cartilage After the Intravenous Stem Cell Injection.

Background: The restoration of auricular cartilage is a major problem of otolaryngology. The low regenerative capacity of cartilage requires alternative approaches such as cell and tissue engineering. Stem cells are one of the ways to repair auricular cartilage damages. The aim of the investigation was the regeneration of an artificial defect of the auricular cartilage of rabbits after the intravenous injection of stem cells. Materials and Methods: The study was carried out on rabbits. A narrow strip of auricular cartilage was surgically removed. A previously prepared suspension of homologous mesenchymal stem cells (5 million) in 0.5 ml physiological solution was injected into the vein of the opposite ear. Tissue samples from the site of the injury were collected after 1, 2, and 3 months. Histological examinations of the tissues were carried out after staining with fuchsin-eosin, azure II-eosin, and according to Weigert. In addition, the amount of interleukin-6 (IL-6) and the transforming growth factor ß1 (TGF-ß1) in the blood serum were determined. Results: The main method of healing is the formation of a connective tissue scar. Yret, an increase of the number of fibroblasts and single islands of the newly formed auricular cartilage was found, which indicates the migration of the injected stem cells to the site of the damage and settling there. The intravenous injection of stem cells did not affect the secretion of pro-inflammatory IL-6, but significantly increased the amount of TGF-ß1. Conclusions: We assume that regenerative processes were stimulated. Nevertheless, they were aimed at quickly restoring the tissue integrity through the typical stages of scar formation. The restoration of cartilage integrity requires additional regulatory factors which will determine the chondrogenic differentiation of stem cells.

Auricular cartilage regeneration using different types of mesenchymal stem cells in rabbits.

BACKGROUND: Cartilaginous disorders comprise a wide range of diseases that affect normal joint movement, ear and nose shape; and they have great social and economic impact. Mesenchymal stem cells (MSCs) provide a promising regeneration alternative for treatment of degenerative cartilaginous disorders. This study aimed to compare therapeutic potential of different types of laser activated MSCs to promote auricular cartilage regeneration. Twelve adult rabbit allocated equally in four groups, all animals received a surgical mid auricular cartilage defect in one ear; Group I (Positive control) injected sub-perichondrially with phosphate-buffered saline (PBS), Group II (ADMSC-transplanted group) injected adipose-derived MSCs (ADMSCs), Group III (BMMSCs-transplanted group) received bone marrow-derived MSCs (BMMSCs), and Group IV (EMSC-transplanted group) received ear MSCs (EMSCs) in the defected ear. The auricular defect was analyzed morphologically, histopathologically and immunohistochemically after 4 weeks. In addition, a quantitative real-time polymerase chain reaction was used to examine expression of the collagen type II (Col II) and aggrecan as cartilage growth factors. RESULTS: The auricles of all treatments appeared completely healed with smooth surfaces and similar tissue color. Histopathologically, defective areas of control positive group, ADMSCs and EMSCs treated groups experienced a small area of immature cartilage. While BMMSCs treated group exhibited typical features of new cartilage formation with mature chondrocytes inside their lacunae and dense extracellular matrix (ECM). In addition, BMMSC treated group showed a positive reaction to Masson's trichrome and orcein stains. In contrary, control positive, ADMSC and EMSC groups revealed faint staining with Masson's trichrome and Orcein. Immunohistochemically, there was an intense positive S100 expression in BMMSCs (with a significant increase of area percentage + 21.89 (P < 0.05), a moderate reaction in EMSCs (with an area percentage + 17.97, and a mild reaction in the control group and ADMSCs (area percentages + 8.02 and + 11.37, respectively). The expression of relative col II and aggrecan was substantially highest in BMMSCs (± 0.91 and ± 0.89, respectively). While, Control positive, ADMSCs and EMSCs groups recorded (± 0.41: ± 0.21, ± 0.6: ± 0.44, ± 0.61: ± 0.63) respectively. CONCLUSION: BMMSCs showed the highest chondrogenic potential compared to ADMSCs and EMSCs and should be considered the first choice in treatment of cartilaginous degenerative disorders.

Application of septal extension grafts with auricular cartilage in rhinoplasty. / 耳廓软骨鼻中隔延伸支架移植物在鼻整形术中的应用.

OBJECTIVES: Rhinoplasty is one of the most common cosmetic surgeries in China. Septal extension grafts (SEG) have been widely used in rhinoplasty, but there are few reports on SEG derived from ear cartilage. This study aims to explore the effectiveness and stability of auricular cartilage nasal SEG transplantation in Chinese rhinoplasty. METHODS: A retrospective analysis of 35 rhinoplasty patients admitted from September 2019 to March 2022 has been conducted. Among them, 29 patients underwent rhinoplasty for the first time and 6 patients underwent rhinoplasty with the age of 18-32 (average 22.4) years old. The postoperative follow-up was 3-28 (average 18.5) months. The improvement of the nose shape was observed. The changes of the nose tip angle, nasolabial angle, and nasofrontal angle were compared between before and after the operation, and the complications were recorded. RESULTS: All patients who underwent rhinoplasty with a septal extension grafts constructed from the concha cavity and concha cartilage showed significant improvement in nasal contour. The preoperative nasal tip angle, nasolabial angle, and nasofrontal angle were significantly improved compared with 3 months after operation (all P<0.001), and there was no significant difference between 3 months and 14 months after operation (all P>0.05). The appearance of nasal cavity was satisfactory in 32 patients after operation. Columella deviation occurred in 2 patients and 1 patient complained of downward rotation of the nasal tip, which was satisfied after readjustment of the graft. CONCLUSIONS: The simplified SEG derived from auricular cartilage can provide stable support for the nasal tip, the nasal shape is natural after operation, and minimal trauma of unilateral auricle cartilage transplantation remains.

Surgical Treatment for Empty Nose Syndrome Using Autologous Dermal Fat: Evaluation of Symptomatic Improvement.

Background: Empty nose syndrome (ENS) is caused by nasal turbinate surgery. The standard treatment for ENS is an inferior meatus augmentation procedure (IMAP) in which autologous tissue such as auricular cartilage, rib cartilage, or artificial material is transplanted into the nasal cavity. However, some challenges like a very small auricular cartilage are associated with these autologous tissue types. Moreover, since using rib cartilage is a highly invasive technique, the scar on the chest from where the harvesting is done is easily visible, and the artificial material is susceptible to infection. We used autologous dermal fat (ADF) in IMAPs in our study for the following reasons: the quantity of ADF could be increased or reduced as needed, ADF is considered a safer option than rib cartilage because it is harvested from superficial tissue, it is superior in terms of cosmetic appearance to harvested rib cartilage, and it has a lower risk of infection than any artificial material.Objective: The purpose of our study was to investigate the efficacy and safety of IMAPs using ADF.Methods: We included nine patients with ENS who underwent an IMAP using ADF. The patients' backgrounds and responses to the Empty Nose Syndrome 6-Item Questionnaire (ENS6Q) were recorded. Changes in each item of the ENS6Q before and after surgery (up to 3 months) were analyzed.Results: The postoperative ENS6Q total score and parameters were significantly better than their preoperative counterparts. Nasal dryness improved slightly less than other symptoms. There were no complications.Conclusions: The IMAP using ADF was effective in improving ENS symptoms; however, some physiological functions were difficult to improve, and dryness persisted. Autologous dermal fat is larger than auricular cartilage, less invasive than rib cartilage, and has a lower risk of infection than artificial material.