Surgical-Based Classification for Microtia

Reconstruction of Concha-Type Microtia Using a Delayed Postauricular Skin Flap

SUMMARY

Understanding how to remove and retain the relatively large residual auricle is important in concha-type microtia reconstruction. The authors present a method for concha-type microtia reconstruction using a delayed postauricular skin flap. A total of 40 patients with concha-type microtia who underwent ear reconstruction using a delayed postauricular skin flap were retrospectively examined. Reconstruction was performed in three stages. The first stage consisted of preparing a delayed postauricular skin flap and dealing with the residual auricle including removal of the upper residual auricular cartilage. In the second stage, an autogenous rib cartilage framework was placed and covered with a delayed postauricular skin flap, postauricular fascia flap, and autologous medium-thickness skin graft. The ear framework was carefully articulated and secured with the retained residual auricular cartilage to achieve a smooth junction between the two. The third stage involved modification of the reconstructed ear. Patients were followed up for 12 months after ear reconstruction. All reconstructed auricles had a good appearance, and there was a smooth connection between the reconstructed auricle and the residual ear, with similar color as well as a flat and thin scar. All patients were satisfied with the results.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Extracellular Vesicles Derived from Auricular Chondrocytes Facilitate Cartilage Differentiation of Adipose-Derived Mesenchymal Stem Cells

PURPOSE

Adipose-derived mesenchymal stem cell (ADSC)-based therapies have been utilized for cartilage regeneration because of their multi-lineage differentiation ability. However, commonly used cartilage inducers such as the transforming growth factor beta-3 (TGF-β3) may be prone to cartilage dedifferentiation and hypertrophy. The directional differentiation of elastic cartilage is limited nowadays. Extracellular vesicles (EVs) have been reported to influence the specific differentiation of mesenchymal stem cells (MSCs) by reflecting the composition of the parental cells. However, the role of auricular chondrogenic-derived EVs (AC-EVs) in elastic chondrogenic differentiation of ADSCs has not yet been reported.

RESULTS

AC-EVs isolated from the external ears of swine exhibited a positive effect on cell proliferation and migration. Furthermore, AC-EVs efficiently promoted chondrogenic differentiation of ADSCs in pellet culture, as shown by the elevated levels of COL2A1, ACAN, and SOX-9 expression. Moreover, there was a significantly higher expression of elastin and a lower expression of the fibrotic marker COL1A1 in comparison with that achieved with TGF-β3. The staining results demonstrated that AC-EVs promoted the deposition of cartilage-specific matrix, which is in good concordance with the real-time polymerase chain reaction (RT-PCR) results.

CONCLUSIONS

Auricular chondrogenic-derived EVs are a crucial component in elastic chondrogenic differentiation and other biological behaviors of ADSCs, which may be a useful ingredient for cartilage tissue engineering and external ear reconstruction.

NO LEVEL ASSIGNED

This journal requires that authors 42 assign a level of evidence to each submission to which 43 Evidence-Based Medicine rankings are applicable. This 44 excludes Review Articles, Book Reviews, and manuscripts 45 that concern Basic Science, Animal Studies, Cadaver 46 Studies, and Experimental Studies. For a full description of 47 these Evidence-Based Medicine ratings, please refer to the 48 Table oôf Contents or the online Instructions to Authors 49 www.springer.com/00266 .

Assessing Adult Patients with Facial Deformities for Injectable Treatment: Do Current Classification Systems and Methodologies Meet Important Patient Needs?

BACKGROUND

Many individuals are affected by facial deformities. Injectable aesthetic treatments can often be used to improve appearance and/or dynamic function. However, to best meet the needs of these patients, broadly applicable methodologies are required for classifying the deformity, assessing severity, and developing a treatment strategy.

OBJECTIVE

To assess whether any published systems could be used for this purpose.

METHODS

Thirty-eight searches were conducted in PubMed (1999-2019; in English). Forty-two publications were identified describing novel classification systems for adult facial deformity. They were analyzed against a checklist of 10 characteristics defining an "optimal" system-based on appropriate anatomical coverage, wide usability across types of deformity, user-friendliness, applicable underlying methodology, and ability to guide treatment with injectables.

RESULTS

None of the systems met more than 7 of the 10 checklist criteria; none were usable across multiple types of deformity or provided a recommendation for treatment with injectables.

CONCLUSION

There remains a need for a broadly applicable system for classifying adult facial deformities ahead of injectable therapy. The checklist provides a developmental framework. With the increasing popularity and accessibility of injectables, this diverse and complex demographic is at risk of mismanagement without superior methods for devising treatment strategies.

The Utility of Smartphone 3D Scanning, Open-Sourced Computer-aided Design, and Desktop 3D Printing in the Surgical Planning of Microtia Reconstruction: a Step by Step Guide and Concept Assessment

Introduction

Microtia, a congenital anomaly of the auricle with a wide spectrum of presentation with challenging reconstruction. Management depends on its severity with variable reconstructive options. Preoperative planning is crucial to achieve better results and decrease operative time. In this article, we aim to show the utility of an affordable technology with the use of a smartphone, an open-source computer-aided design (CAD) software, and a desktop 3D printer in planning future ear location for unilateral microtia reconstruction in step-by-step fashion.

Methodology

Facial 3D scanning was done using a smartphone that has a three-dimensional capture system. The scan was then used in an open-sourced CAD software. A mirror image mask was created by reflecting normal side anatomic features to the abnormal side. The mask constitutes the desired area for reconstruction given the ear anthropometrics. Finally, the model was 3D printed and fitted to the patient in which incision marking and framework location was planned.

Discussion

Ear reconstruction requires careful assessment and specific technicality in its anthropometric measures. One important aspect in surgical planning resides in future ear location that varies between person to person. This variability makes the reconstructive option more customized based on the patient's needs. The utility of CAD software in the measurement and planning can help predict and optimize postoperative results as possible; however, it has major technical demands and added surgical fees.

Conclusion

Herein, we demonstrate the efficacy of an easy-to-use system beneficial for preoperative planning that is affordable, time-saving, and cost effective.

[Anthropometric measurements of moderate concha-type microtia after auricular cartilage unfolding]

Objective

To explore the anthropometric changes of the auricle after auricular cartilage unfolding in moderate concha-type microtia patients, so as to provide the basis to help evaluate surgical timing and prognostic.

Methods

A total of 33 children with moderate concha-type microtia, who were treated with auricular cartilage unfolding between October 2016 and September 2018 and met the inclusive criteria, were included in the study. There were 24 boys and 9 girls with an average age of 1.4 years (range, 1-3 years). Sixteen cases were left ears and 17 cases were right ears. The follow-up time was 12-23 months (mean, 17.5 months). The affected auricular detailed structures were observed and quantitatively analyzed before operation and at immediate after operation. The width, length, and perimeter of auricle before operation and at immediate after operation and at last follow-up were noted with three dimensional-scanning technology. The normal auricle was noted as control.

Results

There were (7.5±1.0) and (11.3±0.8) structures of the affected auricle at pre- and post-operation, respectively, showing significant difference between pre- and post-operation ( t=23.279, P=0.000). The length, width, and perimeter of the affected auricle constantly increased after operation, and there were significant differences between pre-operation and immediately after operation and between immediately after operation and last follow-up ( P<0.05). The differences of length, width, and perimeter of the affected auricle between immediately after operation and last follow-up were (3.13±1.44), (2.44±0.92), and (8.50±3.76) mm, respectively. And the differences of length, width, and perimeter of the normal auricle between pre-operation and last follow-up were (3.16±1.54), (2.35±0.86), and (9.79±4.60) mm, respectively. There was no significant difference in the differences of length, width, and perimeter between the affected auricle and the normal auricle ( P>0.05).

Conclusion

The auricular cartilage unfolding in treatment of the moderate concha-type microtia can receive more ear structures and increase auricle sizes, which make it possible for free composite tissue transplantation. In addition, the affected and the contralateral normal auricles have a very similar growth rate and it offers the theoretical foundation for the early treatment for moderate concha-type microtia.

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.

Classification of the concha-type microtia and their new suitable treatment strategies without autogenous costal cartilage grafting

OBJECTIVE

Numerous corrective methods have been successfully applied in concha-type microtia reconstruction over the past several decades, and autogenous rib cartilage grafting has become a routine technique in a two or three-stage operation. However, it still remains a challenge due to the effective use of the large volume of the remnant cartilage and skin involved. The objective of this study was to clarify how this remnant cartilage and skin could be manipulated for new suitable treatment strategies without autogenous costal cartilage grafting.

METHODS

A total of 424 patients with concha-type microtia operated at our Center from January of 2012 to June of 2019 have been reviewed and analyzed cases. At the same time, a classification system for grading the severity of concha-type microtia was created on the basis of anatomical findings and ear size.

RESULTS

A total of 436 ear cases (involving 424 patients), showing concha-type microtia, were included in our study and reviewed through medical records, photographs, analysis of surgical methods, and postoperative outcomes. The concha-type microtia were classified into four graded types: Grade I (n = 151), Grade II (n = 101), Grade III (n = 93), and Grade IV (n = 79). A total of 352 ears in 345 patients with Grade I to III concha-type microtia were followed up for 1 month to 7 years (average, 14.7 months). 329 patients (95.4%) were satisfied with the aesthetic outcomes of the corrected ear.

CONCLUSIONS

Individual corrective methods and aesthetic outcomes for patients with Grade I to III of deformity were described in this study. The authors present new suitable approaches according to a progressive classification system which provide conservative and individualized methods of treatment in early stages of life.

Morbidity in Patients With Separation of Cartilaginous Framework: Temporoparietal Fascia Flap and Treatment With Dermal Regeneration Template

BACKGROUND

The full creation of an ear requires 2 reconstruction stages. In the second stage of reconstruction, the cartilaginous framework placed at first stage is separated from the head creating an auriculocephalic sulcus. Then a piece of rib cartilage is placed in the sulcus to maintain this separation and is covered with tissue that allows the integration of a full-thickness skin graft.

METHODS

A descriptive study based on the pre and postoperative medical records and photographic archives of patients diagnosed with microtia who underwent separation of the cartilaginous framework from February 2010 to July 2015 in the Plastic and Reconstructive Surgery Department at Hospital General Dr. Manuel Gea González.

RESULTS

Fifty-four patients met the selection criteria. The temporoparietal fascial flap was performed on 85% (n = 46), and 8 cases with random occipito-temporal fascial flap in association to a dermal regeneration template. The average time at the operating room was 177 minutes in patients with temporoparietal fascial flap versus 84.5 minutes in dermal regeneration template. The complication rate was 25.9% (n = 14), being similar rate with both techniques.

CONCLUSIONS

Coverage with dermal regeneration template and random occipito-temporal fascia flap as an alternative use instead of temporoparietal fascial flaps, offers good postoperative results, lower operating times, and similar rate of complications, with the advantage of producing no visible scars and reserve the temporoparietal fascial flap for possible exposure of the cartilaginous framework.