External ear reconstruction in hemifacial microsomia

Assessment and Identification of Improvement Areas for Facial Symmetry in Hemifacial Microsomia (Type IIB) Using Three-dimensional Measurements

Background

Surgical planning for hemifacial microsomia (HFM) patients often involves planning the amount of maxillary movement and mandibular bone distraction from three-dimensional (3D) volumetric images constructed from computed tomography scans. By representing anatomical indicators for facial symmetry in X, Y, and Z coordinates, we identified the more challenging areas in correcting facial asymmetry.

Methods

The study included five HFM patients with a mean age of 22.2 years, all diagnosed with HFM (type IIB). We established measurement points with high reproducible 3D coordinates on the 3D volumetric images obtained from computed tomography scans for before surgery, treatment objectives, and after surgery. We assessed the symmetry of measurement points between the affected side and nonaffected side at each time point.

Results

In the before-surgery group, significant differences were observed between the affected side and nonaffected side in X,Y (excluding Palatine foramen, upper molar, canine) and Z coordinates for measurement items. In the treatment objectives group, no differences were observed between the affected side and nonaffected side in X, Y, and Z coordinates, resulting in facial symmetry. In the after-surgery group, significant differences were observed in Y coordinates in the mental foramen area, and significant differences were observed in z axis measurement items in the canine and mental foramen areas.

Conclusions

It is evident that relying solely on a front view assessment is insufficient to achieve facial symmetry. Particularly, both anterior-posterior and vertical improvements in the area near the mental foramen on the affected side are necessary.

Prograde transposition for anteriorly low-set earlobe in lobule-type microtia reconstruction

BACKGROUND

Lobule transposition, a common procedure in auricle reconstruction, has been successfully performed over the past few decades. However, the transposition methods for unilateral microtia with evident asymmetry of bilateral earlobe positions still remain a challenge. The objective of this study was to investigate the application of prograde transposition for anteriorly low-set earlobes.

METHOD

A total of 25 patients with lobule-type microtia with anteriorly low-set residual earlobe underwent prograde transposition during auricle reconstruction between 2020 and 2022. The post-operative earlobe aesthetic assessment and patient satisfaction were evaluated, and the data on any complications that occurred when followed-up were collected. This study provides a comprehensive analysis and summary of the techniques used in earlobe transposition for auricular reconstruction.

RESULTS

The patients with evident asymmetry between the residual and healthy earlobes were usually concomitant with hemifacial microsomia and the residual ear was located in the anterior and lower region. No instances of flap necrosis, hematoma, or wound dehiscence were observed following auricular reconstruction. The mean aesthetic score of the auricle was 3.52, with 23 patients attaining good or excellent aesthetic outcomes. The mean Visual Analog Scale satisfaction score was 3.68, with 24 patients reporting relative satisfaction or satisfaction.

CONCLUSION

The prograde transposition of anteriorly low-set earlobe in lobule-type microtia reconstruction can effectively ensure adequate blood supply, enhance aesthetic appearance, and significantly improve patient satisfaction.

Anatomical variant of the superficial temporal artery in temporoparietal fascia flap for microtia reconstruction

BACKGROUND

Single-stage microtia auricular reconstruction is becoming more relevant. The determining factor is a temporoparietal fascia flap (TPF) with both branches of the superficial temporal artery (STA). There are not many studies regarding vascular branching in people with microtia.

METHODS

We conducted an anatomical study on the TPF flap harvested during single-stage endoscopic-assisted microtia auricular reconstruction from May 2018 to July 2021. We observed the flaps under endoscopic and surgical microscopes to determine several variables (vascular size, number of frontal/parietal branches, distance from the branching location to the estimated external ear canal, distance from the frontal artery to projected course of facial nerve's frontal branch, etc.).

RESULTS

The study included 55 flaps from 54 patients. Of the 55 flaps, 50 (90.9%) had a parietal branch, and all 55 (100%) had a frontal branch with a mean diameter of 0.98 and 0.91 mm, respectively. Regarding the frontal artery, 1.8%, 25.5%, 50.9%, 16.35% and 5.45% had 0-4 traverse frontal branch(es), respectively. The mean distance from the frontal artery to the estimated course of the frontal nerve was 10.56 mm. Parietal artery absence is more likely in patients with severe hemifacial microsomia or STA trunk go under the auricular cartilage remnants (p < 0.05). Either frontal or parietal artery absence or small diameter can cause necrosis. Frontal arteries travelling near the frontal nerve may result in post-operative nerve palsy.

CONCLUSIONS

Microtia auricular reconstructive surgery is always a big challenge for plastic surgeons. Anatomical variants are common. A detailed anatomical description of the STA, with the help of microsurgery and endoscopy, allows arterial-based flap designing and harvest, which tremendously improves surgical success rate by diminishing flap necrosis and nerve damage.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Determination of Novel, Cranium-Based Relationships for Construct Placement in Microtia Reconstruction for Hemifacial Microsomia Patients

OBJECTIVE

Determine if the ideal location of the construct in microtia reconstruction for hemifacial microsomia (HFM) can be more accurately derived from measurements on the cranium.

DESIGN

High-resolution computerized tomography (CT) images were analyzed through craniometric linear relationships.

SETTING

Our tertiary care institution from 2000 to 2021.

PATIENTS/PARTICIPANTS

Patients diagnosed with HFM and microtia, who had high-resolution craniofacial CT scans, yielding 36 patients accounting for 44 CT scans.

MAIN OUTCOME MEASURE(S)

First, the integrity of the posterior cranial vault among HFM patients was determined. If proven to be unaffected, it could be used as a reference in the placement of the construct. Second, the position of the ear in relation to the cranium was assessed in healthy age-matched controls. Third, if proven to be useful, the concordance of these cranium-based relationships could be validated among our HFM cohort.

RESULTS

The posterior cranial vault is unaffected in HFM (P > .001). Further, craniometric relationships between the tragus and the Foramen Magnum, as well as between the tragus and the posterior cranium, have been shown to be highly similar and equally precise in predicting tragus position in healthy controls (P > .001). These relationships held true across all age groups (P > .001), and importantly among HFM patients, where the mean absolute difference in predicted tragus position never surpassed 1.5 mm.

CONCLUSIONS

Relationships between the tragus and the cranium may be used as an alternative to distorted facial anatomy or surgeon's experience to assist in pre-operative planning of construct placement in microtia reconstruction for HFM patients.

Vascular variation of temporoparietal fascia in microtia associated with hemifacial microsomia

The study analyzed vascular variations in microtia associated with hemifacial microsomia (HFM). A retrospective analysis was conducted on 47 patients with microtia and HFM, who underwent computed tomography angiography between November 2011 and May 2022. The vascular course and branching supplying the TPF were analyzed. Craniometric measurements were conducted to determine the horizontal distance from the porion and fronto-zygomatic suture (F-Z suture) to the vessels. On the affected side, the TPF was primarily supplied by either the superficial temporal artery (STA) or the postauricular artery-originated STA (Po-STA). The Po-STA (n = 29) was more prevalent than the STA (n = 18), and mostly exhibited a single frontal branch (n = 20). Craniometric analysis revealed that the Po-STA was closer to the porion, ear vestige, and F-Z suture than the STA on the non-affected side. Furthermore, a significant correlation was observed between the severity of mandibular hypoplasia and presence of Po-STA variation (Cramer's V = 0.498, p = 0.005). Microtia associated with HFM exhibits vascular variations in the TPF - in particular, a unique Po-STA variation. The Po-STA is prone to injury during ear reconstruction because of its proximity to the external auditory canal and ear vestige. Surgeons should be cautious of these anatomical variations for safer ear reconstruction procedures, and utilize preoperative imaging for meticulous planning.

Morphologic Variability of Bone and Soft Tissue in Microtia With Hemifacial Microsomia

Objective: Microtia patients with hemifacial microsomia (HFM) have a host of distinct anatomical disorder of skeletal and soft tissue asymmetries. The purpose of this study was to assess soft tissue discrepancies in microtia patients with HFM and their correlation with skeletal discrepancies. Methods: A total of 42 patients were enrolled and studied prospectively using a 3-dimensional superimposition and color mapping of the soft and hard tissues. Mirroring techniques created perfectly symmetric models for comparison. Differences between affected and normal sides were evaluated in 5 areas: retroauricular mastoid, malar, maxillary frontal, mandibular frontal, and gonion areas. Pearson correlations were used to assess the relationship between skeletal and soft tissue asymmetry. Results: Hard tissue asymmetry ranged from 0.79 mm (mandibular frontal) to 1.29 mm (malar), while soft tissue asymmetry ranged from 1.34 mm (maxillary frontal) to 5.26 mm (retroauricular mastoid). Correlations between skeletal and soft tissue asymmetry varied, with the strongest correlation observed at the retroauricular mastoid area and the weakest at the maxillary frontal area. Conclusion: There was a high correlation between bone and soft tissue hypoplasia at the retroauricular mastoid area, while the other evaluated areas showed poor correlation between skeletal and soft tissue asymmetries. Clinicians should assess each component separately for optimal treatment planning in microtia patients with HFM.

Firm elevation of the auricle in reconstruction of microtia with a retroauricular fascial flap wrapping two titanium plate struts

BACKGROUND

Reconstruction of the cephaloauricular sulcus in patients with microtia in ear reconstructions remains challenging. Costal cartilage and other support materials wedge were used for ear elevation. Each material has its disadvantages. To reconstruct a stable cephaloauricular sulcus and reduce costal cartilage harvesting, we used two titanium plate struts to support the costal cartilage framework.

METHODS

A titanium plate strut was designed. The angle of the strut was 60°, the arm length was 0.8 cm, and the width was 0.5 cm. The thickness was 0.6 mm. Four small pores are formed on the titanium plate. The implanted framework was separated from the underlying bed. Two titanium plate struts were fixed on the raised ear framework, tendon, and periosteum, and then wrapped with a turned-over retroauricular fascia flap. The raw surface was covered with a split-thickness skin graft, harvested from the scalp.

RESULTS

From 2019 to 2022, 51 patients underwent second-stage operations. All patients were followed up for a minimum of 6 months. The auricular projection was well-maintained, and the cephaloauricular sulcus of the constructed auricle was acceptable in 50 patients. There was one infection, and the titanium plate struts were removed, which resulted in shrinking cephaloauricular angles.

CONCLUSIONS

Titanium plate is effective as a supportive material to obtain the proper and firm projection of the constructed auricle. It provides a new option for patients whose costal cartilage volume is insufficient or who do not want to have the costal cartilage harvested again.

Surgical Microtia Reconstruction in Hemifacial Microsomia Patients: Current State and Future Directions

Background:

Hemifacial microsomia (HFM) is one of the most common congenital craniofacial disorders. Among many other features, microtia is present in the large majority of these patients. However, mainly due to the unilateral hypoplastic anatomy, microtia reconstruction among this patient population remains a reconstructive challenge for plastic surgeons. Given that no clear standards exist, an evidence-based synthesis of the literature was devised.

Methods:

A systematic search of Pubmed, Medline, and Embase was carried out, in accordance with the PRISMA guidelines. Studies discussing surgical microtia reconstruction for HFM patients were retained. Qualitative data regarding study design, challenges addressed, specific recommendations, and their respective strengths/limitations were extracted from each. Retrieved recommendations were consolidated and assigned a level of evidence grade.

Results:

Although only 11 studies were included in this review, these provided 22 main recommendations regarding the eight HFM-specific challenges identified, which were of either grade C (n = 5) or D (n = 17). Included studies addressed construct location (n = 7), the low hairline (n = 6), soft tissue construct coverage (n = 6), earlobe reconstruction (n = 6), construct projection (n = 5), anomalies of the relevant neurovascular systems (n = 2), retroauricular construct coverage (n = 2), and sizing of the construct (n = 2).

Conclusions:

Given the many persisting reconstructive challenges regarding surgical microtia reconstruction for HFM patients, the authors present a comprehensive and evidence-based consolidation of recommendations specific to these challenges. The authors hope this systematic review can appropriately guide plastic surgeons and will ultimately improve care for this patient population.

Microtia Part II: Post-Operation and Complications Management Lessons from 1012 Ear Reconstruction Operations

BACKGROUND

Ear reconstruction presents challenges for surgeons, not only during the pre-operation and in-operation stages, but also post-operation. The post-operation stage and the treatment of complications are critical to the overall success of ear reconstruction surgery.

METHODS

This article, the second of two articles setting out details and precautions for each step of the ear reconstruction process for microtia patients, covers post-operative care: negative pressure drainage, bandaging and fixing, nursing, treatment of complications and satisfaction survey.

RESULTS

Over the period Jan 2015-July 2021, our surgical team treated 77 complications in 1012 microtia ear reconstructions. This article presents the key learnings from this high volume of operations. All complications were treated promptly and the shape of the auricle was preserved as much as possible. Patients were surveyed after the operation and expressed satisfaction with the shape of the reconstructed external auricle. Three typical cases involving different types of complications are described.

CONCLUSIONS

This article deals in detail with the post-operation stage. We share our cumulative surgical experience gained over 20 years, especially the latest practical lessons gleaned over the last six and a half years.

LEVEL OF EVIDENCE II

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 .

Auricular reconstruction with modified expanded two-flap method in Goldenhar Syndrome: 7-Year experiences

BACKGROUND

Goldenhar Syndrome (GS) is a systematic polymalformational disease characterized by microtia, hemifacial microsomy, ocular anomalies, abnormal vertebra and other deformities. These congenital malformations brought severe physical and mental stress to the patients. Auricular reconstruction has always been the primary appeal of the patients and their families to achieve a better facial balance and harmony. However, multiple deformities made it a great challenge to perform this technique. In this study, we reported a modified expanded two-flap method of auricular reconstruction, which is more applicable for patients with Goldenhar Syndrome.

METHODS

Between January of 2012 and September of 2019, 69 cases of Goldenhar Syndrome underwent auricular reconstruction with the modified expanded two-flap technique. Auricular reconstruction was performed in three surgical stages. In the first stage, a 50 ml kidney-shaped tissue expander was embedded in mastoid region and the retroauricular skin expanded. In the second stage, the autologous rib cartilage was harvested and the ear framework fabricated. The expander was further removed, and then enveloped by the expanded flap, retroauricular fascial flap and a free skin graft. In the third stage, the reconstructed ear was further trimmed, including lobule transposition and tragus reconstruction.

RESULTS

The patients were followed for 6 months to 7 years. There were 63 cases (91.3%) responded satisfied outcomes in size, shape, position and bilateral symmetry. One case suffered expander leakage and tissue expansion accomplished after the expander was replaced. Hematoma was occurred in four cases and removed to complete the reconstruction. Complications of cartilage exposure were observed in one case.

CONCLUSION

Modified expanded two-flap method is effective and safe in auricular reconstruction for patients of Goldenhar syndrome with long term satisfying results. Level of Evidence IV.

Reconstruction of Congenital Microtia and Anotia: Analysis of Practitioner Epidemiology and Postoperative Outcomes

BACKGROUND

Microtia refers to a congenital malformation of the external ear that is associated with a range of functional, psychosocial, aesthetic, and financial burdens. The aim of this study was to analyze the epidemiology and postoperative complication profile of microtia reconstruction.

METHODS

A retrospective review was conducted using data from the 2012-2017 the American College of Surgeons National Quality Improvement Program Pediatric databases. Patients with a diagnosis of microtia or anotia were identified using International Classification of Diseases codes. Demographics and postoperative complications were analyzed using Chi-square and t tests for categorical and continuous variables, respectively. Multivariable regression was performed to control for confounding variables.

RESULTS

A total of 466 cases were analyzed, of which 290 (62.2%) were performed by plastic surgeons and 176 (37.8%) by otolaryngologists (ear, nose, and throat physicians [ENT]). Autologous reconstruction was the predominant approach [76.2% of cases (n = 355)] in this cohort. ENT physicians operated on a significantly younger patient population (mean age 8.4 ± 3.2 years versus 10.0 ± 3.2 years, P< 0.001) and had higher rates of concurrent atresia/middle ear repair [21.0% (n = 37) versus 3.7% (n = 17)] compared with plastic surgeons. The rate of all-cause complications was 5.9% (n = 17) in the plastic surgery cohort and 4.0% (n = 7) in the ENT cohort (P= 0.372). Multivariable regression did not reveal any statistically significant predictors for all-cause complications.

CONCLUSIONS

Reconstruction of the external ear for patients with microtia/anotia is a safe procedure, with low rates of postoperative complications, readmissions, and reoperations. Autologous reconstruction remains the preferred modality for repair of the external ear and simultaneous atresiaplasty/middle ear repair does not increase the risk of complications.

Predictors for Unfavorable Projection of the Constructed Auricle following Ear Elevation Surgery in Microtia Reconstruction

BACKGROUND

Nagata's two-stage technique for microtia reconstruction using autologous costal cartilage consists of the implantation of a fabricated cartilage framework and the elevation of the constructed auricle. Achieving long-lasting, sufficient projection of the auricle is a goal of second-stage surgery; however, unfavorable outcomes have been seen in some patients, with suboptimal long-term elevation. The present study aimed to investigate prognostic factors that might contribute to adverse outcomes following the ear elevation operation.

METHODS

Outcomes of patients with congenital microtia who underwent auricular reconstruction with a modified Nagata technique between January of 2007 and June of 2015 were reviewed. Unfavorable elevation was defined as cases with an auriculocephalic angle less than 20 degrees or with a shallow auricular sulcus requiring revision operations. Univariate and multivariate analyses were conducted to identify independent predictors for the unfavorable elevation.

RESULTS

A total of 309 patients representing 323 cases were analyzed with a median follow-up period of 26 months. The mean age of the patients was 15.1 years. The majority of cases had lobule-type microtia. Hemifacial microsomia was present in 114 cases. Canalplasty was performed in 117 cases before the auricular elevation. Unfavorable elevation was observed in 72 cases (22.3 percent). Multivariate analyses showed that the presence of hemifacial microsomia and performance of canalplasty less than or equal to 12 months before the ear elevation operation were independent risk factors for the unfavorable elevation.

CONCLUSION

Several preoperative factors, including combined anomalies and operative timing and sequences, might influence the outcomes of the ear elevation operation.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Splinting After Ear Reconstruction

BACKGROUND

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

MATERIAL AND METHODS

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

CONCLUSIONS

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

Anatomical variants of the superficial temporal artery in patients with microtia: a pilot descriptive study

Superficial temporal artery (STA) based pedicled fascial flap plays a pivotal role in ear reconstruction for microtia patients. There is paucity of literature on the anatomy of the STA in microtia patients. The present study aimed to describe any possible anatomical variations seen in the STA of patients afflicted with microtia. Pre-operative carotid computer tomographic angiography images of patients under the microtia database of Plastic and Reconstructive Surgery Unit at a tertiary medical centre were selected and 3-dimensionally reconstructed. Measurements were made on the 3D reconstructed computed tomographic angiography images of the STA on both the sides of the microtic ear and the non-microtic ear to assess its various anatomical parameters. We managed to obtain a total of 39 computed tomographic angiography images of STAs for analysis. There was a significant difference in the number of main branches of STA between the two groups (P=0.006). The proportion of ears with 2 main branches was higher in the non-microtia group (89.5%) compared to the microtia group (45.0%). A significant difference was found in the STA diameter between the two groups (P=0.012). The mean diameter of STA in the non-microtia group was larger by 0.4 mm. Furthermore, the median angle of STA was larger on the side of the non-microtic ears compared to that of microtic ears by 24.5°, with a P-value of 0.011. The results of the study may be of clinical importance while planning and performing ear reconstructive surgeries using STA based pedicled fascial flaps.

Extended lateral thoracic fasciocutaneous biosynthetic flap for reconstruction of full-thickness partial external ear defects: an experimental study

External ear reconstruction is a controversial topic in reconstructive plastic surgery. Here, we prepared a pedicled biosynthetic flap for full-thickness, partial ear defects in rabbits. We operated on six adult female New Zealand rabbits weighing 3-4 kg. The dimensions of the lateral thoracic fasciocutaneous flap were 7 × 6 cm. The flap was elevated based on one of the bilaterally located internal thoracic arteries, which were dissected proximally. The pedicled flap was folded in two, and polypropylene mesh was sandwiched in the middle. The flap was adapted to a defect of 3.5 × 3 cm in diameter. In fact, the defect was created before elevation of the flap. Rabbits were followed up for 4 weeks, at the end of which they were killed and their ears were evaluated histopathologically. The survival rate of the rabbits was 100 %. All pedicled biosynthetic flaps were viable, but one showed partial (20 %) necrosis (1/6) and one was partially detached (1/6). Macroscopic (color, thickness, texture) and histological (polymorphonuclear leukocyte invasion in the skin, subcutaneous tissue, and at the junction between the polypropylene mesh and the flap) features of the flap were compared to the ipsilateral ear. A new technique was developed for partial external ear reconstruction with sufficient inner skeletal support and outer skin lining. Level of evidence Level NA.