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.

Object: Three-stage expansion method represents the most common form of microtia reconstruction in hemifacial microsomia (HFM). Although the complication related expander has lowered owing to the current advances, bony depression in mastoid region in microtia patients with hemifacial microsomia was observed in clinical work. The aim of this study was to quantify bony depression after retroauricular expander implantation and identify associated factors. Methods: 42 patients were enrolled and studied prospectively utilizing 3-dimensional (3D) evaluation. Craniofacial computed tomography (CT) was performed before the first (pre-expansion) and the second stage (post-expansion) and 3D quantification was done to quantify bony depression in mastoid region by using CT data. Univariate analysis was performed to identify factors associated with bony depression in mastoid region. Results: The mean level of mastoid depression was 0.83 mm (range: 0.07-4.08 mm), and the max level of mastoid depression was 1.40 mm (range: 0.20-6.65 mm). In univariate analysis, capsular duration of expansion and expansion volume were associated factors with mastoid depression. Conclusion: This study showed the possibility of mastoid depression following expander implantation for microtia reconstruction in hemifacial microsomia. Plastic surgeons should be aware of the possibility and associated factors of bony depression in mastoid region following expander implantation to optimize microtia reconstruction for patients with HFM.

Introduction : Autologous costal cartilage framework placement is currently the gold standard in patients with microtia. In this article, we present the modifications developed by the author, generally following the principles established by Nagata, and discuss the technical details that have led us to achieve consistently stable and good long-term outcomes for auricular reconstruction in microtia. Materials and Methods : A retrospective review of microtia reconstruction performed from 2015 to 2021 was done. Those who underwent primary reconstruction for microtia and with a minimum follow-up of 6 months with documented photographs were included. Those who underwent secondary reconstruction for microtia and those who did not follow-up for a minimum period of 6 months were excluded. Outcomes were assessed with regard to appearance, and durability of the result. Influence of certain changes like delaying reconstruction until 15 years of age, use of nylon for framework fabrication, etc. over the outcome were assessed. Results : Of 11 ears reconstructed at less than 15 years of age, only one patient (9%) had a good long-term outcome, whereas of the 17 ears reconstructed at greater than 15 years of age, nine patients (53%) had a good long-term outcome. In our experience, infections and wire extrusions were the significant events related to severe cartilage resorption. Conclusion : In our experience, delaying the first stage to 15 years or later, using double-armed nylon sutures, and reducing the projection of the third layer of the framework in select cases have helped to improve our outcomes. Second stage of reconstruction can be avoided if patient is satisfied with the projection achieved in the first stage.

Parotid gland fistula after microtia reconstruction is relatively rare, with only 3 cases having been reported in the literature. It may be caused by the presence of an accessory parotid gland or surgical damage to parotid gland tissues. The principal treatment is dressing the wound. Here, we report the first case of parotid fistula after microtia reconstruction using a delayed retroauricular flap, which healed following wound dressing and an injection of botulinum toxin type A (CBTXA) into the parotid gland.

Infection after reconstructive surgery for microtia is a technical challenge. This can be a sign of cholesteatoma formation by entrapment of epithelium in the middle or outer ear, specifically when the patient does not respond to first choice antibiotic therapy and debridement. Two patients with microtia presented themselves with severe infections after ear reconstruction. In both cases cholesteatoma was diagnosed as the cause of the infection. After cholesteatoma management an additional surgical procedure was necessary to improve the esthetic outcome. The plastic surgeon should identify possible signs of cholesteatoma after reconstruction of the auricle.

The use of a semilunar cartilage block to elevate a reconstructed ear does not always achieve a well-defined auriculocephalic sulcus. Herein, we modified the conventional crescent cartilage block through sculpting a concavity at its posterior surface, with the aim of improving the retroauricular contour. The study aimed to verify the effectiveness and reliability of this modified cartilage block through a retrospective cohort study.
A retrospective review of patients who underwent Nagata microtia reconstruction between October 2017 and November 2018 were conducted. The esthetic outcomes of auricular projection and cranioauricular sulcus in patients who accepted the modified semilunar block were compared with those of patients who underwent the same procedure using the traditional crescent pad.
A total of 163 (84 of the modified group and 79 of the traditional group) patients were included. The mean (median) esthetic scores for ear projection in the modification and traditional groups were 3.13 (3) and 3.06 (3), respectively. The rate of favorable ear projection in the modification group (83.3%) was similar with that in the traditional group (78.5%) (p = 0.550). The mean (median) esthetic scores for cranioauricular sulcus in the modification and traditional groups were 2.51 (3) and 2.90 (3), respectively. The rate of favorable retroauricular sulcus in the modification group was 75.9%, whereas that in the traditional group was 51.2%, with the differences reaching statistical significance (p = 0.001).
The concave crescent-shaped block can improve the contour of the auriculocephalic sulcus under the premise of ensuring the ear projection.

Fibrin gel-based scaffolds have promising potential for microtia reconstruction. Autologous chondrocytes and chondrocyte cell sheets are frequently used seed cell sources for cartilage tissue engineering. However, the aesthetic outcome of chondrocyte-based microtia reconstruction is still not satisfactory. In this study, we aimed to fabricate the chondrocytes/chondrocyte-microtissues laden fibrin gel auricular scaffold for microtia reconstruction. We designed a unique auricular mold that could fabricate a fibrin gel scaffold resembling human auricle anatomy. Primary chondrocytes were harvested from rabbit auricular cartilage, and chondrocyte cell sheets were developed. Chondrocyte-microtissues were prepared from the cell sheets. The mixture of chondrocytes/chondrocyte-microtissues was laden in fibrin gel during the auricular scaffold fabrication. The protrusions and recessed structure in the auricular scaffold surface were still clearly distinguishable. After a one-week in vitro culture, the 3 D structure and auricular anatomy of the scaffold were retained. And followed by eight-week subcutaneous implantation, cartilaginous tissue was regenerated in the artificial auricular structure as indicated by the results of H&E, Toluidine blue, Safranin O, and type II collagen (immunohistochemistry) staining. Protrusions and depressions of the auricular scaffold were slightly deformed, but the overall auricular anatomy was maintained after 8-week in vivo implantation. Extracellular matrix components content were similar in artificial auricular cartilage and rabbit native auricular cartilage. In conclusion, the mixture of chondrocytes/chondrocyte-microtissues laden fibrin gel auricular scaffold showed a promising potential for cartilaginous tissue regeneration, suggesting this as an effective approach for autologous chondrocyte-based microtia reconstruction.

OBJECTIVE: The Bonebridge (BB) is a newly designed transcutaneous bone conduction hearing implant. We describe, for the first time, simultaneous BB implantation and different surgical techniques of auricular reconstruction for microtia patients with aural atresia/stenosis.
METHODS: Ten patients with unilateral or bilateral microtia underwent BB implantation combined simultaneously with either total auricular reconstruction using bespoke hand-carved Medpor framework or second stage auricular projection using autologous costal cartilage framework. Auditory aided and unaided sound fields were evaluated using (1) a pure-tone average (PTA4), (2) a speech reception threshold (SRT), and (3) a Speech Discrimination Score (SDS) at a sound level of 65 dB SPL.
RESULTS: All patients and their families were satisfied with the aesthetic outcome of their constructed ears with no requests for further revision. No major complications were encountered. One patient developed minor partial skin graft epidermolysis that healed uneventfully, and another patient had a three month period of auditory acclimatization to the BB device that resolved. Postoperatively, the mean aided PTA4 decreased by 35.35 dB, while the SRT was 54.5 dB HL unaided and 28 dB HL with use of a BB sound processor. The SDS increased by 16.4%-65 dB SPL.
CONCLUSIONS: Simultaneous BB implantation during either total auricular reconstruction or framework projection for microtia patients who have aural atresia/stenosis is feasible and safe. This approach reduces operative stages, thereby minimizing schooling/occupational disruption and time to total microtia reconstruction and auditory rehabilitation.

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UNASSIGNED: Microtia reconstruction is a challenging procedure, especially in developing nations. The most complex part is learning how to fabricate a framework from costal cartilage. We herein propose a training regimen for ear reconstruction with the use of a plastic eraser.
UNASSIGNED: The texture of a plastic eraser made from polyvinyl chloride is similar to that of human costal cartilage. The first step of the training is carving out the sixth through eighth rib cartilages from a block of plastic eraser. The second step is a fabrication of the framework from plastic rib cartilages, referring to a template from the intact auricle.
UNASSIGNED: As plastic erasers are inexpensive and universally available, inexperienced surgeons can repeatedly perform this framework training. Following several of these training sessions in developing nations, the co-authors and local surgeons successfully performed their microtia reconstructions in a reasonable operative time.
UNASSIGNED: This realistic carving model allows surgeons to gain experience before performing an actual ear reconstruction, even in resource-constrained circumstances.