An update on auricular reconstruction: three major auricular malformations of microtia, prominent ear and cryptotia

Seminars in Plastic Surgery: Pediatric Ear Anomalies and Reconstruction

Congenital ear anomalies affect 15 to 20% of neonates and can be categorized as either auricular deformations or malformations. Deformations involve a fully developed, albeit abnormally shaped, chondrocutaneous framework, which makes them amenable to correction with ear molding within the first few months of life. Malformations involve hypoplastic or fully absent auricular structures that require augmentation with alloplastic and/or autogenous reconstruction. The goal of this article is to outline the various auricular deformities and malformations, followed by a description of the latest clinical management options, both nonsurgical and surgical, by auricular anomaly.

Vertical mattress suture applied as "Tension band fixation" for the antihelix creation and prominent ear treatment: 104 case reports

BACKGROUND

Prominent ears were the most common auricular deformity. Different surgical techniques, such as cartilage-cutting techniques and suturing techniques, are available for treatment. The horizontal mattress suture technique, represented by the Mustard technique, is widely accepted, while the vertical mattress suture technique is rarely discussed in otoplasty.

METHOD

A total of 104 cases of prominent ear deformities were treated from January 2017 to December 2020. Several hypothetical "tension bands" perpendicular to the natural curvature of the antihelix were introduced for the surgical design and determination of the position of the antihelix fixation, and vertical mattress sutures were placed accordingly for the auricular cartilage fixation.

RESULT

Follow-up ranged from 3 months to 2 years. No complications, such as hematoma, infection, or poor wound healing, were observed. Three patients had recurrence within two months post operation, and one complained about the overfolded antihelix. Three cases had suture exposure, but the shape of the auricle was not affected after suture removal. The surgical result was evaluated according to the overall shape of the auricle, including the shape of the antihelix, the improvement of the prominent, the surgical marks, and the bilateral symmetry. A total of 98 patients (94.23%) rated the results as "very satisfactory" or "satisfactory".

CONCLUSION

The vertical mattress suture applied as "tension band fixation" could provide stable cartilage fixation with the natural appearance of the antihelix formation. In addition, the technique could fit a wide range of indications with a low risk of complication and reoccurrence.

A New Method of Correcting Cryptotia by Changing Mechanical Fulcrum After Constricted Cartilage Overturned

BACKGROUND

Many techniques have been introduced to correct cryptotia. The previous methods are releasing the constricted cartilage and changing the mechanical fulcrum partly to the right position. However, some patients are still not satisfied with the treatment results, due to cryptotia recurrence and insufficient superior 1/3 width. This study aimed to develop a new method for completely changing the mechanical direction of constricted cartilage for correcting cryptotia.

METHODS

From 2007 to 2020, twenty-four cryptotia patients were treated. During surgical reconstruction, the retroauricular skin flap was elevated, the posterior aspect of the upper auricular cartilage was completely exposed, and the abnormal insertion of the auricular intrinsic muscles detached. The sharply curved antihelical cartilage was cut and overturned, and the scalp skin flap was undermined and advanced toward the postauricular sulcus. The edge of the retroauricular scalp flap is fixed on the mastoid periosteum. The incision was closed.

RESULTS

Eighteen patients had unilateral cryptotia, and six had bilateral cryptotia. Relatively favorable results were obtained in the follow-up period (range, 6-48 months). There were no cases of skin necrosis, complications, or revision surgery.

CONCLUSIONS

The main advantages of this technique are the surgically reproducible results, and that it can be applied to most cases. The method described in this paper could potentially increase the width of the upper third of the auricle and reduce recurrence rate, while also leaving an inconspicuous scar and a satisfactory auricular contour. It is suggested that this technique could be an alternative method of cryptotia correction.

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 .

Postoperative outcomes of autologous rib graft for microtia repair in children: A NSQIP study

OBJECTIVE

To compare the effect of surgical specialty and patient factors on 30-day postoperative outcomes and complications for children undergoing autologous costochondral grafting for microtia reconstruction.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program Pediatric (NSQIP-P) database was searched from 2012 through 2017 for patients who underwent autologous rib grafting (CPT 21230). The group was further filtered for coexisting ICD 9 or 10 code for microtia (744.23, Q17.2) as an indication for surgery. Outcomes analyzed included patient demographics, medical comorbidities, admission type (inpatient vs. outpatient), operative time, surgeon specialty, length of hospital stay (LOS), complications, and readmission.

RESULTS

A total of 375 pediatric patients were identified of which 157 were female and 218 were male. Mean age at time of surgery was 9.6 years. Postoperative complications and readmission occurred in 5.6% and 3.5% of patients, respectively. Surgical site infection was the most common complication. Average operative time was 246.9 min. When comparing Otolaryngology to Plastic Surgery with multivariate analysis, there was no difference in admission type (OR 1.00, p = 0.993), complication rate (OR 0.91, p = 0.744), readmission (OR 0.68, p = 0.576), operative time (p = 0.471) or total LOS (p = 0.266).

CONCLUSION

The present study demonstrated postoperative complications and readmission rates following microtia repair as reported by the NSQIP-P database. Overall complication and readmission rates were low. No significant risk factors were identified on multivariate analysis. There were no differences between surgical specialty for complication rate, operative time, hospital stay or readmission when accounting for demographic data and comorbidities.

Management of Congenital Auricular Anomalies

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Describe normal ear anatomy and development, and evaluate the patient's ears for differences in shape, size, prominence, and symmetry. 2. Identify common congenital ear deformities, including prominent ear, macrotia, Stahl ear, cryptotia, constricted ear, and lobule anomalies. 3. Describe both early nonoperative management and operative techniques for correction of these ear deformities. 4. Be aware of advantages and disadvantages of common and emerging techniques for correction of pediatric ear deformities.

SUMMARY

Whereas severe ear malformations such as microtia/anotia are rare, other ear deformities, such as prominent ear, Stahl ear, and cryptotia, are common. Although these ear deformities result in minimal physiologic morbidity, their psychological and cosmetic impact can be significant. Identifying these common deformities and understanding how they differ from normal ear anatomy is critical to their management. In cases where a deformity is identified in neonatal life, ear molding may obviate the need for surgery. Although various surgical techniques have been described for correction of common ear deformities, the surgeon should follow a careful stepwise approach to address the auricular deformity or deformities present. By using such an approach, complications may be minimized and predictable aesthetic outcomes achieved.

The ideal auricular protrusion - An interactive perceptual pilot study

PURPOSE

Excessive ear protrusion (prominauris) can negatively affect facial appearance. Because the concept of an ideal auriculocephalic angle is controversial, however, it is difficult to define when an obtrusive auricle requires surgical intervention. It is often assumed that angles exceeding 30° require corrective surgery. However, little is known about public perception of ear protrusion. This study aimed to assess perceptions of different degrees of auricular protrusion.

MATERIALS AND METHODS

We conducted an interactive panel survey. Male and female evaluators assessed digitally processed cloned images of a male and female model that depicted various ear protrusions ranging from 0° to 90°. Predictor variables were the sex of the evaluator, the sex of the clone and the extent of auricular protrusion. The outcome variable was the overall attractiveness of auricular appearance.

RESULTS

Forty-four evaluators (students of dental medicine, mean age 25.43 years) participated in the study: 22 women and 22 men. The study results revealed sexual dimorphism, with the attractiveness of corresponding male and female clones rated differently. Male evaluators favoured female ear positions that fitted closer to the head; preferred alignments for female clones were: 18° (Mean) ± 9.38° (SD), p = 0.006; for male clones: 30° ± 7.94°, p = 0.003. Ear protrusion starts to negatively affect aesthetic appearance for male evaluators at positions of 42° ± 4.87° (female clone) and 54° ± 8.22° (male clone), p = 0.001. The panel of evaluators agreed to perceive angles of 21-24° ± 8.10° (female clones), ± 8.33° (male clones), as the ideal degree of protrusion in both sexes (p = 0.158).

CONCLUSION

In this study, perception of ear appearance depended on the sex of both the evaluator and the clone being assessed. Obtrusive ears were more readily accepted in male faces than in female ones. Nevertheless, the overall panel perception shows a preference for rather close fitting, unobtrusive ear alignments. For planning of corrective ear surgery, a target angle of approximately 22° can be considered as a desirable result.

An analytical study of neocartilage from microtia and otoplasty surgical remnants: A possible application for BMP7 in microtia development and regeneration

To investigate auricular reconstruction by tissue engineering means, this study compared cartilage regenerated from human chondrocytes obtained from either microtia or normal (conchal) tissues discarded from otoplasties. Isolated cells were expanded in vitro, seeded onto nanopolyglycolic acid (nanoPGA) sheets with or without addition of bone morphogenetic protein-7 (BMP7), and implanted in nude mice for 10 weeks. On specimen harvest, cartilage development was assessed by gross morphology, histology, and RT-qPCR and microarray analyses. Neocartilages from normal and microtia surgical tissues were found equivalent in their dimensions, qualitative degree of proteoglycan and elastic fiber staining, and quantitative gene expression levels of types II and III collagen, elastin, and SOX5. Microarray analysis, applied for the first time for normal and microtia neocartilage comparison, yielded no genes that were statistically significantly different in expression between these two sample groups. These results support use of microtia tissue as a cell source for normal auricular reconstruction. Comparison of normal and microtia cells, each seeded on nanoPGA and supplemented with BMP7 in a slow-release hydrogel, showed statistically significant differences in certain genes identified by microarray analysis. Such differences were also noted in several analyses comparing counterpart seeded cells without BMP7. Summary data suggest a possible application for BMP7 in microtia cartilage regeneration and encourage further studies to elucidate whether such genotypic differences translate to phenotypic characteristics of the human microtic ear. The present work advances understanding relevant to the potential clinical use of microtia surgical remnants as a suitable cell source for tissue engineering of the pinna.

Non-surgical correction of cryptotia and the analysis of treatment time and other influence factors

OBJECTIVE

To explore correlations between post-treatment outcomes of non-surgical correction for cryptotia and treatment time and other influence factors.

METHODS

Forty-seven consecutive patients with 64 cryptotias were treated with the adjusted external stretching device and followed up over 12 months. A subjective evaluation scale was designed for patients to collect clinical data. Pretreatment and posttreatment evaluation were conducted by two blinded investigators. The correlations between influence factors and outcomes were explored through fractional polynomial method, multiple logistic regression, and robust linear regression methods.

RESULTS

Thirty-five patients with 49 cryptotias were included. Twenty-nine cryptotias (23 patients) have been successfully managed. Two of 17 unilateral cryptotias achieved nearly complete symmetry. The final optimal cutoff value for initiating treatment time is 6 months and for the duration of treatment per day is 5 h per day. Positive relationships between initiating treatment time >6 months and onset time, type II and onset time, initiating treatment time >6 months and effect stabilization time were observed.

CONCLUSIONS

Initiating treatment time <6 months and duration of treatment per day >5 h benefit for the posttreatment outcomes. Patients wearing the device under 6 months old would have earlier onset time and effect stabilization time. It is hard to achieve complete bilateral symmetry in unilateral patients. The adjustable devices can used for the auricles with different sizes and removed and equipped conveniently.

Aesthetic Otoplasty: Principles, Techniques and an Integrated Approach to Patient-Centric Outcomes

BACKGROUND

Otoplasty is a century-old procedure that, through continued modifications, now has over two hundred different procedures described in the literature. In this article, we seek to describe the anatomy and principles of aesthetic otoplasty, as well as some of the key contributions to aesthetic otoplasty. This article will also outline some of the most commonly used techniques today and associated patient outcomes.

METHODS

We present a review of the literature of relevant anatomy, pathophysiology and common techniques and outcomes. We also provide a discussion of several patients with associated techniques and outcomes.

RESULTS

The treatment of prominent ear has developed through manipulation and experimentation. The outcomes are defined by the native anatomy, the surgical technique and the attention to patient-centered outcomes.

CONCLUSION

Aesthetic otoplasty remains one of the most important surgical techniques and common procedures in plastic surgery. Using an integrated approach guided by known principles as well as patient goals allows for optimal outcome in aesthetic otoplasty.

LEVEL OF EVIDENCE V

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 .

The Use of Temporoparietal Fascia Flap for Surgical Treatment of Traumatic Auricle Defects

Background

Auricular reconstruction is 1 of the biggest challenges of facial plastic surgery. The aim of this study was to evaluate the efficacy of 1-stage reconstruction of an auricle using a temporoparietal fascia flap (TPFF).

Methods

In this nonrandomized study, autologous auricle bodies with emergency condition and cartilaginous graft from projection of a costal arch from the VI-VII ribs were used. Temporal fascia sample with vascular pedicle (a temporal artery with the accompanying veins) by the Z-shaped incision of skin in temporal area for auricular reconstruction was extracted. Skin grafts were taken from the supraclavicular area or from the left or right flank. Grafts of partial auricle bodies (n = 8) along with cartilaginous framework from a costal arch (n = 21) were used for auricle reconstruction. The follow-up period studied after 6 months in 29 operated patients.

Results

The graft of partial auricle bodies or the graft of a cartilaginous framework from a costal arch presented a perfect auricular reconstruction. By avoiding a difficult microsurgery and its possible complications, the use of TPFF led to beneficial results in 75% and 90.4% of cases, respectively. Overall, no major complication (alopecia, hematoma, or necrosis) occurred, and further surgery was not required.

Conclusion

TPFF is a technique of choice for surgical treatment of traumatic auricle defects.

Surgical correction of cryptotia combined with an ultra-delicate split-thickness skin graft in continuity with a full-thickness skin rotation flap

BACKGROUND

Cryptotia is a common congenital ear deformity in Asian populations. In cryptotia, a portion of the upper ear is hidden and fixed in a pocket of the skin of the mastoid. Here we describe our method for cryptotia correction by using an ultra-delicate split-thickness skin graft in continuity with a full-thickness skin rotation flap.

PATIENTS AND METHODS

We developed a new method for correcting cryptotia by using an ultra-delicate split-thickness skin graft in continuity with a full-thickness skin rotation flap. Following ear release, the full-thickness skin rotation flap is rotated into the defect, and the donor site is covered with an ultra-delicate split-thickness skin graft raised in continuity with the flap.

RESULTS

All patients exhibited satisfactory release of cryptotia. No cases involved partial or total flap necrosis, and post-operative outcomes using this new technique for cryptotia correction have been more than satisfactory.

CONCLUSIONS

Our method of using an ultra-delicate split-thickness skin graft in continuity with a full-thickness skin rotation flap to correct cryptotia is simple and reliable.

The Boom in 3D-Printed Sensor Technology

Future sensing applications will include high-performance features, such as toxin detection, real-time monitoring of physiological events, advanced diagnostics, and connected feedback. However, such multi-functional sensors require advancements in sensitivity, specificity, and throughput with the simultaneous delivery of multiple detection in a short time. Recent advances in 3D printing and electronics have brought us closer to sensors with multiplex advantages, and additive manufacturing approaches offer a new scope for sensor fabrication. To this end, we review the recent advances in 3D-printed cutting-edge sensors. These achievements demonstrate the successful application of 3D-printing technology in sensor fabrication, and the selected studies deeply explore the potential for creating sensors with higher performance. Further development of multi-process 3D printing is expected to expand future sensor utility and availability.

Accurate Measurements of the Skin Surface Area of the Healthy Auricle and Skin Deficiency in Microtia Patients

Background:

The limited cranial skin covering auricular implants is an important yet underrated factor in auricular reconstruction for both reconstruction surgery and tissue engineering strategies. We report exact measurements on skin deficiency in microtia patients and propose an accessible preoperative method for these measurements.

Methods:

Plaster ear models (n = 11; male:female = 2:1) of lobular-type microtia patients admitted to the University Medical Center Utrecht in The Netherlands were scanned using a micro-computed tomographic scanner or a cone-beam computed tomographic scanner. The resulting images were converted into mesh models from which the surface area could be calculated.

Results:

The mean total skin area of an adult-size healthy ear was 47.3 cm², with 49.0 cm² in men and 44.3 cm² in women. Microtia ears averaged 14.5 cm², with 15.6 cm² in men and 12.6 cm² in women. The amount of skin deficiency was 25.4 cm², with 26.7 cm² in men and 23.1 cm² in women.

Conclusions:

This study proposes a novel method to provide quantitative data on the skin surface area of the healthy adult auricle and the amount of skin deficiency in microtia patients. We demonstrate that the microtia ear has less than 50% of skin available compared with healthy ears. Limited skin availability in microtia patients can lead to healing problems after auricular reconstruction and poses a significant challenge in the development of tissue-engineered cartilage implants. The results of this study could be used to evaluate outcomes and investigate new techniques with regard to tissue-engineered auricular constructs.

Prevention of Recurrence in the Surgical Correction of Cryptotia Using Local Flaps With a Cartilage Wedge Graft

Cryptotia attributable to deficient posterior skin coverage frequently recurs. Because local flaps cover only the posterior aspects of the defective upper auricular cartilage and lack functional support to resist collapse of the helix, especially if severe helical cartilage anomalies are present, additional support is required to prevent the postoperative recurrence of this anomaly. The authors present cases of cryptotia treated using local flaps including a Z-plasty or formation of a trefoil flap with an additional cartilage wedge graft on the cephaloauricular sulcus to enhance projection of the helix. The combination of a graft with a local flap using a large Z-plasty or trefoil flap efficiently corrects the cryptotia, and is associated with minimal visible scarring and few complications, including recurrence.

Developing an Ear Prosthesis Fabricated in Polyvinylidene Fluoride by a 3D Printer with Sensory Intrinsic Properties of Pressure and Temperature

An ear prosthesis was designed in 3D computer graphics software and fabricated using a 3D printing process of polyvinylidene fluoride (PVDF) for use as a hearing aid. In addition, the prosthesis response to pressure and temperature was observed. Pyroelectric and piezoelectric properties of this ear prosthesis were investigated using an astable multivibrator circuit, as changes in PVDF permittivity were observed according to variations of pressure and temperature. The results show that this prosthesis is reliable for use under different conditions of pressure (0 Pa to 16,350 Pa) and temperature (2 °C to 90 °C). The experimental results show an almost linear and inversely proportional behavior between the stimuli of pressure and temperature with the frequency response. This 3D-printed ear prosthesis is a promising tool and has a great potentiality in the biomedical engineering field because of its ability to generate an electrical potential proportional to pressure and temperature, and it is the first time that such a device has been processed by the additive manufacturing process (3D printing). More work needs to be carried out to improve the performance, such as electrical stimulation of the nervous system, thereby extending the purpose of a prosthesis to the area of sensory perception.

In vivo needle-based electromechanical reshaping of pinnae: New Zealand White rabbit model

IMPORTANCE

Electromechanical reshaping (EMR) is a low-cost, needle-based, and simple means to shape cartilage tissue without the use of scalpels, sutures, or heat that can potentially be used in an outpatient setting to perform otoplasty.

OBJECTIVES

To demonstrate that EMR can alter the shape of intact pinnae in an in vivo animal model and to show that the amount of shape change and the limited cell injury are proportional to the dosimetry.

DESIGN, SETTING, AND SPECIMENS

In an academic research setting, intact ears of 18 New Zealand white rabbits underwent EMR using 6 different dosimetry parameters (4 V for 5 minutes, 4 V for 4 minutes, 5 V for 3 minutes, 5 V for 4 minutes, 6 V for 2 minutes, and 6 V for 3 minutes). A custom acrylic jig with 2 rows of platinum needle electrodes was used to bend ears at the middle of the pinna and to perform EMR. Treatment was repeated twice per pinna, in proximal and distal locations. Control pinnae were not subjected to current application when being bent and perforated within the jig. Pinnae were splinted for 3 months along the region of the bend using soft silicon sheeting and a cotton bolster.

MAIN OUTCOMES AND MEASURES

The ears were harvested the day after splints were removed and before euthanasia. Photographs of ears were obtained, and bend angles were measured. Tissue was sectioned for histologic examination and confocal microscopy to assess changes to microscopic structure and cellular viability.

RESULTS

Treated pinnae were bent more and retained shape better than control pinnae. The mean (SD) bend angles in the 7 dosimetry groups were 55° (35°) for the control, 60° (15°) for 4 V for 4 minutes, 118° (15°) for 4 V for 5 minutes, 88° (26°) for 5 V for 3 minutes, 80° (17°) for 5 V for 4 minutes, 117° (21°) for 6 V for 2 minutes, and 125° (18°) for 6 V for 3 minutes. Shape change was proportional to electrical charge transfer, which increased with voltage and application time. Hematoxylin-eosin staining of the pinnae identified localized areas of cell injury and fibrosis in the cartilage and in the surrounding soft tissue where the needle electrodes were inserted. This circumferential zone of injury (range, 1.5-2.5 mm) corresponded to dead cells on cell viability assay, and the diameter of this region increased with total electrical charge transfer to a maximum of 2.5 mm at 6 V for 3 minutes.

CONCLUSIONS AND RELEVANCE

Electromechanical reshaping produced shape change in intact pinnae of rabbits in this expanded in vivo study. A short application of 4 to 6 V can achieve adequate reshaping of the pinnae. Tissue injury around the electrodes increases with the amount of total current transferred into the tissue and is modest in spatial distribution. This study is a critical step toward evaluation of EMR in clinical trials.

LEVEL OF EVIDENCE

NA.

Effects of FGF-2 and OP-1 in vitro on donor source cartilage for auricular reconstruction tissue engineering

OBJECTIVE

Microtia is a congenital partial or total loss of the external ear with current treatment approaches involving autologous construction from costal cartilage. Alternatively, tissue engineering provides possible use of normal or microtia auricular chondrocytes harvested from patients. This study investigated effects in vitro of basic fibroblast growth factor (FGF-2) and osteogenic protein 1 (OP-1) on human pediatric normal and microtia auricular chondrocytes and their potential proliferation and differentiation for cellular expansion. A working hypothesis was that FGF-2 promotes proliferation and OP-1 maintains an auricular phenotype of these cells.

METHODS

Two patients, one undergoing otoplasty and one an ear construction, yielded normal and microtia auricular chondrocytes, respectively. The two donor sets of isolated chondrocytes were equally divided into four experimental cell groups. These were controls without added growth factors and cells supplemented with FGF-2, OP-1 or FGF-2/OP-1 combined. Cells were cultured 3, 5, 7, and 10 days (3 replicates/time point), counted and assayed by RT-qPCR to determine elastin and types II and III collagen gene expression.

RESULTS

Compared to control counterparts, normal and microtia chondrocytes with OP-1 alone were similar in numbers and varied in elastin and types II and III collagen expression over all culture times. Compared to respective controls and chondrocyte groups with OP-1 alone, normal and microtia cell groups with FGF-2 had statistically significant (p<0.05) enhanced proliferation and statistically significant (p<0.05) decreased elastin and types II and III collagen expression over 10 days of culture.

CONCLUSIONS

FGF-2 effects on normal and microtia chondrocytes support its use for increasing cell numbers while OP-1 maintains a chondrocyte phenotype, otherwise marked by increasing type III collagen expression and cellular dedifferentiation to fibroblasts in culture.