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New Strategies for Tragus and Antitragus Complex Fabrication in Lobule-Type Microtia Reconstruction

Xu, Zhicheng M.D., Ph.D.; Zhang, Ruhong M.D. Ph.D.; Zhang, Qun M.D., Ph.D.; Xu, Feng M.D., Ph.D.; Li, Datao M.D., Ph.D.; Li, Yiyuan M.D., Ph.D.

Plastic and Reconstructive Surgery: October 2019 - Volume 144 - Issue 4 - p 913-921
doi: 10.1097/PRS.0000000000006043
Pediatric/Craniofacial: Original Articles
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Background: The creation of a high-defining tragus and antitragus complex remains a demanding challenge during staged lobule-type microtia reconstruction. The success of the complex carving relies greatly on proper operation of the cartilage, which is commonly residual cartilage of various sizes. The authors discuss the relevant details for sculpting the tragus and antitragus complex based on cartilage remnants in various conditions.

Methods: A series of 562 lobule-type microtia patients underwent autogenous costal cartilage auricular reconstruction between 2007 and 2016. Because of the various sizes and shapes of the remnant cartilage used for the tragus and antitragus complex reconstruction, the authors have described possible scenarios for fabrication and introduced relevant tactics for appropriate treatment.

Results: Corresponding methods for various scenarios in tragus and antitragus complex fabrication have been shown to demonstrate a satisfactory appearance. The results demonstrate the achievement of a harmonious tragus and antitragus complex for the integrity of a constructed ear.

Conclusions: Proper use of the residual cartilage for tragus and antitragus complex sculpture plays a vital role in acquiring a favorable contour of the auricle in microtia reconstruction. The introduced approach enhances the aesthetics and functionality of the complex for modern life.

CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Shanghai, People’s Republic of China

From the Department of Plastic and Reconstructive Surgery, Shanghai Ninth People’s Hospital, Shanghai JiaoTong University School of Medicine.

Received for publication September 13, 2018; accepted February 25, 2019.

Disclosure:None of the authors has a financial interest to declare in relation to the content of this article.

Ruhong Zhang, M.D., Ph.D., Department of Plastic and Reconstructive Surgery, Shanghai Ninth People’s Hospital, Shanghai JiaoTong University School of Medicine, No. 639, Zhi Zao Ju Road, Shanghai 200011, People’s Republic of China, zhangruhong@163.com

The tragus and antitragus complex, located in the lateral and inferior part of the auricle, is a comparatively diminutive subunit in lobule-type microtia reconstruction but plays an important role in defining a harmonious outline of the auricle. It gives the impression of a relatively deep concha despite the missing acoustic meatus. Moreover, a favorable reconstructed tragus and antitragus complex can also accommodate earphones if necessary. In previous reports, multiple surgical techniques have been illuminated for significant improvement of the reconstruction of the complex.1–7 However, the complicated conditions of the remnant cartilage of various sizes pose one of the most demanding challenges in tragus and antitragus complex fabrication. In this article, the authors have developed alternative solutions for such possible scenarios and demonstrate favorable reconstructed auricles with harmonious tragus and antitragus complexes created by these refinements.

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PATIENTS AND METHODS

A total of 562 lobule-type microtia patients, ranging in age from 6 to 42 years, underwent reconstruction with autogenous costal cartilage between 2007 and 2016. Overall, 523 patients underwent unilateral reconstruction, and 39 patients underwent bilateral reconstruction. A total of 397 patients were men, and 165 were women.

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Harvesting the Rib Cartilage

We generally harvest the sixth, seventh, and eighth costal cartilages from the contralateral chest; if necessary, the ninth is also prepared for use. The synchondrosis of the sixth and seventh costal cartilages is used for the base frame reconstruction. The helical element is normally formed by the eighth costal cartilage. The ninth costal cartilage is only used to lengthen or heighten a slender eighth cartilage if necessary. Nonbiodegradable hydroxyapatite bone cement with epoxide acrylate maleic resin is used as the support material during ear elevation; thus, extra costal cartilage harvesting and banking are unnecessary.

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Tragus and Antitragus Complex Fabrication

After completion of the main part of the framework, the residual cartilage, mostly from the sixth or seventh costal cartilages, is used for fabrication of the tragus and antitragus complex. Because of the various sizes of the cartilage remnants, various approaches to carving the tragus and antitragus complex have gradually evolved through our experience (Fig. 1).

Fig. 1.

Fig. 1.

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Scenario 1: Integrated Tragus and Antitragus Complex

Referring to the morphometric study of the normal human auricle,8–10 we find that the tragus and antitragus complex can be well constructed with a comparatively large residual block if it is no smaller than 2 or 3 × 2 or 3 cm. In our experience, the tragus, antitragus, and intertragic notch can be well defined in an integral whole with a perfect curve fluctuating up and down. This condition usually occurs in adult and adolescent patients with strong and adequate cartilage remaining for use.

In addition, one cartilage strut is routinely added under the tragus during the fabrication with the purpose of allowing the tragus’s protrusion and stabilization and the deepening of the conchal bowl (Fig. 2).

Fig. 2.

Fig. 2.

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Scenario 2: Separated Tragus and Antitragus Complex

If the residual cartilage is not as large as that in scenario 1 but should be more than approximately 1 to 1.5 × 2 to 3 cm, the tragus and antitragus can be fabricated separately and fixed on the base frame to form the final complex.

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Part A: Antitragus Fabrication

If the cartilage ready for the antihelix is long and wide enough, the antihelix and antitragus can be constructed integrally. Otherwise, the antitragus can be made individually with a smaller piece of cartilage. In addition, more attention should be paid to the lower part of the base frame, primarily the seventh rib cartilage. If it is not wide enough based on the template from the normal side, a block of cartilage with the same thickness as the base frame can be added laterally to broaden its width. Then, the prepared antitragus can be fixed in the appropriate position on the widened base frame (Fig. 3).

Fig. 3.

Fig. 3.

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Part B: Tragus Fabrication

We normally adopt two methods for tragus fabrication for this type.

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Type A.

The residual cartilage is routinely placed horizontally. It is in situ configuration such that the height of the tragus is the thickness of the rib cartilage. Referring to the normal side as a template, the contour of the tragus is sketched and then carved. In addition, another cartilaginous cube is added under the original tragus to augment the tragus’s protrusion, enhance the conchal depth, and secure the reconstructed tragus in a stable projection, similar to that in scenario 1 (Fig. 4).

Fig. 4.

Fig. 4.

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Type B.

Different from type A, the cartilage piece is placed upright. That is, the piece is reoriented 90 degrees from the in situ configuration such that the height of the tragus is the width of the rib cartilage. In this way, the outline of the tragus is high enough, and no additional cartilage strut must be appended. More importantly, a gentle slope of the groove is carved into the medial side of the tragus to smoothly integrate the contracted skin flap after the operation. Therefore, an almost C shape of the erected tragus from the lateral view ensures the appropriate height and stability in the structure (Fig. 5).

Fig. 5.

Fig. 5.

Afterward, as reported previously,11,12 a piece of residual cartilage fixed by wire is added between the tragus and the base frame of the inferior crus to reinforce the two end points of the C-shaped framework. The lower end of the strut is not fixed to the base frame until the framework has encircled the subcutaneous pedicle and has been accommodated in the proper place within the skin pocket. In addition, we immobilize the tragus at the base of the soft tissue with a 4-0 braided suture to lessen the projecting pressure upward to the skin flap, which can reduce the occurrence of necrosis of the skin flap and exposure of the cartilage.

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RESULTS

We performed 601 ear reconstructions in 562 consecutive patients with lobular-type microtia using the described method. The follow-up period for all patients ranged from 6 to 36 months. Two patients in scenario 1 (n = 205) complained about the shallow and narrow incisura intertragica at the connection between the tragus and antitragus. Sloughing on the tip of the local flap occurred in four cases in scenario 2 (n = 357). Meticulous ointment coverage was a reliable solution, and no further treatments were needed. The complaints of another three patients in this scenario focused on the overly prominent appearance of the individually reconstructed tragus. Nevertheless, they appeared inconspicuous after the second stage. There were no episodes of pneumothorax, hematoma, keloid, or infection in this series. The following three patients are summarized as examples.

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CASE REPORTS

Case 1

A 19-year-old man presented with lobule-type microtia (Fig. 6). The tragus and antitragus complex were fabricated as an integral whole using our method in scenario 1. Postoperative results 2 years after elevating the framework were satisfactory. The tragus and antitragus complex appeared natural and smooth, which approximated the shape of the normal ear at follow-up.

Fig. 6.

Fig. 6.

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Case 2

The patient in case 2 was a 12-year-old boy whose tragus was made using the type A technique in scenario 2 with a cartilage strut added at the bottom and fixed on a broadened base frame (Fig. 7). The width and depth of the incisura intertragica were appropriate at follow-up. The well-contoured tragus and antitragus appeared vividly detailed, with harmonious and natural features.

Fig. 7.

Fig. 7.

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Case 3

This case was a 13-year-old boy whose tragus was reconstructed upright, as described in scenario 2, type B (Fig. 8). Postoperative results after 7 months were favorable. The tragus and antitragus complex showed clearly defined morphologic features, with no sign of cartilage resorption, deformation, or wire exposure.

Fig. 8.

Fig. 8.

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DISCUSSION

Reproducing the tragus and antitragus complex is one of the most important procedures in auricular reconstruction. First, the complex determines the depth and form of the concha. A successfully reproduced complex ameliorates the aesthetic outcome of the concha and perfectly conceals the missing acoustic meatus in lobule-type microtia reconstruction.13 Moreover, a fluctuant curve and appropriate dimensions of the complex define an appropriate width of the lower half of the reconstructed auricle, which contributes substantially to the cosmetically refined ear with harmonious integrity. Furthermore, it ensures the functionality in accommodating modern technology to wear earphones or hearing aids.14 Therefore, successful structural and functional reconstruction of the complex greatly benefits the patients in regaining confidence in life and integrating into society.15

In addition, we may encounter different predicaments to achieve a satisfactory complex. It is important to present a perfect V-shaped curve and decent interval space of the tragus and antitragus complex. Otherwise, a U-shaped complex is apt to appear if the interval space is too large. Considering the hard-tissue deficiency region beneath the complex, it could not provide adequate projection. Thus, a substantial challenge for us is to develop the proper extent of the complex protrusion, especially to the subunit of the tragus. An overly prominent structure would easily lead to necrosis of the skin flap. In contrast, the structure would appear to be insufficiently prominent if the tragus were not sufficiently high. Moreover, the tragus would be liable to collapse because of unstable fixation or improper cartilage fabrication. In our experience, the strategies to solve the above problems depend mostly on proper application of the residual cartilage for the complex sculpture. If the cartilage has an ideal size and volume, it will demonstrate a harmonious reconstructed subunit with appropriate interspaces and a perfect curve through elaborate fabrication and fixation. However, we have encountered remaining cartilage that varies in size. It is indeed a great challenge for us to determine whether and how to use the cartilage. In this report, we systematically introduce and classify corresponding solutions for such possible scenarios.

If the dimensions of the residual cartilage are sufficient for the tragus and antitragus complex fabrication as described in scenario 1, it is more convenient to properly duplicate the contour and size of the complex. The smooth and fluctuant curve can be defined entirely as a whole. In addition, the mutual distance between the tragus and antitragus is decent regardless of the visual effect or application function. Specifically, the V-shaped structure of the tragus and antitragus is well duplicated. The intertragic notch is presented in a smooth and graceful curve. Moreover, it could even accommodate earphones, similar to the normal side.

We commonly encounter undesirable cartilage left for fabrication. Therefore, we have developed alternative solutions for such possible conditions in scenario 2. We emphasize that proper width of the lower part of the base frame, a footstone of the tragus and antitragus, is of great importance to accurately position and obtain structural harmony of the complex. If the complex is fixed to the narrow base frame without being broadened based on the template from the normal side, it would be off-center to the left or right, top-heavy, and discordant in structure. To solve such problems, we recommend that a piece of cartilage should be added to broaden the narrow base frame and further accommodate the complex in an appropriate position, especially in scenario 2. As the seventh cartilage is commonly wide and sufficient enough in scenario 1, no additional cartilage is needed to broaden the base frame.

The procedure of fabricating the antitragus is flexible according to various cartilage conditions. If possible, the tragus and antitragus or antihelix and antitragus can be rebuilt as a whole if the cartilage is of proper width and length. Otherwise, the antitragus has to be sculpted separately from a smaller piece of cartilage. In our experience, the tragus and antitragus complex is preferred as described above. The antihelix and antitragus complex is the second option. In other words, we would rather build an integral complex than use separate parts because a more fluent curve and less unnecessary incisure are more likely to be demonstrated in a whole structure than in combined portions.

Regardless of whether the tragus and antitragus complex is constructed integrally or separately, determining the appropriate height and stability are central elements, especially in the tragus fabrication, which is an important and comparatively difficult procedure. As we know, the antitragus is commonly treated as the extensive part of the antihelix and sits on the normal or broadened base frame. Thus, it is convenient to make it in a stable situation. However, most of the tragus is extended outside the frame and fixed at the relatively soft base tissue; thus, it is essential to keep it in a stable condition with proper height. Therefore, an additional cartilage strut is usually added beneath the tragus and fixed laterally to the base frame. In this way, the necessary height and stability of the tragus are ensured. In our experience, the final tragus is almost at the same level as the highest point of the antihelix. If it is lower than that point, the tragus would not be protruding enough when placed into the skin pocket. In contrast, when it is placed much higher, the skin flap would not sustain the pressure from the tragus. As a result, the occurrence of skin flap necrosis and cartilage exposure would increase. To prevent such complications and ensure the safety of the skin flap, we recommend that the edge of the tragus be sculpted smoothly and that unnecessary stimulation of the skin flap be limited. More importantly, the tragus is routinely fixed at the base of the soft tissue with a suture to further reduce the projecting pressure upward to the skin flap. Specifically, we avoid any additional pressure from the tragus to the skin flap, and only allow the normal contraction pressure of the skin flap to the tragus at follow-up.

In scenario 2, two techniques of tragus fabrication were illustrated, including a horizontally placed tragus with additional cartilage at the bottom or placed upright with no extra cartilage. Theoretically, the tragus is more stable when fabricated by the former method that provides more contact area with the base tissue. However, we could also take advantage of the latter method to save cartilage, especially if there is no more suitable cartilage to add beneath. In addition, the second method allows us to carve and make the bottom plane flatter to increase the contact area. It is immobilized at the base of the soft tissue with a suture to further reduce the possibility of moving or overturning.

Occasionally, the tragus, antitragus, helix, and antihelix could be made completely as a whole on the base frame if the cartilage is broad and wide enough to entirely define all these structures. This scenario can occur in adults or adolescent patients with strong cartilage but a comparatively smaller auricle, especially in Western patients. Therefore, in Asian patients, we prefer to construct these subunits using additional cartilage and to combine them on the base frame. Overall, the tragus and antitragus complex can be rebuilt with the appropriate protrusion and stability by the techniques introduced in the article.

So far, Nagata’s and Firmin’s techniques have been broadly accepted as standard procedures in microtia reconstruction. To ensure a reliable blood supply to the skin flap, Nagata emphasizes the importance of preserving a subcutaneous pedicle,3 which has been well documented by anatomical preparations.16–18 Firmin does not think that the pedicle is vital to increase flap blood supply.5 Moreover, the framework, accompanied by a projection block for stabilization of the root of the helix to the tragus, which also serves for deepening of the conchal bowl, could be easily accommodated in the proper place within the skin pocket. The maneuver can well be performed without the subcutaneous pedicle, as the lack thereof releases much more flexibility for additions of projection and stabilization pieces between the roots of the helix to the tragus. It really takes us more time to accommodate the framework under the influence of the pedicle. The lower end of the strut is not fixed to the base frame until the framework has rotated, wrapping around the subcutaneous pedicle, and is seated in its appropriate position. Nevertheless, we prefer to keep the subcutaneous pedicle, especially in Asian patients. As we know, the characteristic of skin varies according to race. For example, the skin is thinner and more flexible in Caucasians than in Mongolian patients. It provides numerous advantages, as a much sharper and more clearly defined auricular contour can be attained.19 However, to ensure a reliable blood supply to the tip of the flap, we think it necessary for us to reserve the pedicle in most of our cases. Meanwhile, care must be taken to dissect the skin flap at a moderate layer to avoid injuring the subdermal vascular plexus. In some cases, where skin seems to be thin and elastic, we attempt to follow Firmin’s approach. It occurs more frequently in patients from the western part of our country, where patient race is much closer to Caucasian.

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CONCLUSIONS

Proper use of the residual cartilage for tragus and antitragus complex fabrication is critical to attain a satisfactory contour of the auricle in lobule-type microtia reconstruction. The introduced approach enhances tragus and antitragus complex aesthetics with harmonious integrity that has proven to be realistic and aesthetically pleasing at follow-up.

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PATIENT CONSENT

Patients or the parents or guardians provided written consent for the use of patients’ images.

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ACKNOWLEDGMENTS

The authors thank Françoise Firmin, M.D., Ph.D., Chunxiao Cui, M.D., Ph.D., Tianya Li, M.D., Ph.D., Xia Chen, M.D., and Wei Chen, M.D., Ph.D., for contributing to the work.

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REFERENCES

1. Tanzer RC. Total reconstruction of the auricle: The evolution of a plan of treatment. Plast Reconstr Surg. 1971;47:523–533.
2. Brent B. Technical advances in ear reconstruction with autogenous rib cartilage grafts: Personal experience with 1200 cases. Plast Reconstr Surg. 1999;104:319–334; discussion 335–338.
3. Nagata S. A new method of total reconstruction of the auricle for microtia. Plast Reconstr Surg. 1993;92:187–201.
4. Park C. Subfascial expansion and expanded two-flap method for microtia reconstruction. Plast Reconstr Surg. 2000;106:1473–1487.
5. Firmin F. Ear reconstruction in cases of typical microtia: Personal experience based on 352 microtic ear corrections. Scand J Plast Reconstr Surg Hand Surg. 1998;32:35–47.
6. Zhang Q, Zhang R, Xu F, Jin P, Cao Y. Auricular reconstruction for microtia: Personal 6-year experience based on 350 microtia ear reconstructions in China. Plast Reconstr Surg. 2009;123:849–858.
7. Wilkes GH, Wong J, Guilfoyle R. Microtia reconstruction. Plast Reconstr Surg. 2014;134:464e–479e.
8. Park C. Reconstruction of congenital tragal malformations accompanied by dystopic cartilage growth (accessory tragus). Plast Reconstr Surg. 2015;135:1681–1691.
9. Wang B, Dong Y, Zhao Y, Bai S, Wu G. Computed tomography measurement of the auricle in Han population of north China. J Plast Reconstr Aesthet Surg. 2011;64:34–40.
10. Alexander KS, Stott DJ, Sivakumar B, Kang N. A morphometric study of the human ear. J Plast Reconstr Aesthet Surg. 2011;64:41–47.
11. Kasrai L, Snyder-Warwick AK, Fisher DM. Single-stage autologous ear reconstruction for microtia. Plast Reconstr Surg. 2014;133:652–662.
12. Xu Z, Zhang R, Zhang Q, Xu F, Li D. The importance of costal cartilage framework stabilization in microtia reconstruction: Anthropometric comparison based on 216 cases. J Plast Reconstr Aesthet Surg. 2014;67:1651–1658.
13. Chin WS, Zhang R, Zhang Q, et al. Techniques for improving tragus definition in auricular reconstruction with autogenous costal cartilage. J Plast Reconstr Aesthet Surg. 2011;64:541–544.
14. Perez CF, Gaball CW. Functional and aesthetic tragal reconstruction in the age of mobile electronic devices. Case Rep Otolaryngol. 2016;2016:2591705.
15. Ha JH, Jeong E, Lazaro H. Tragus formation during concha-type microtia repair using a chondrocutaneous island flap. Arch Craniofac Surg. 2018;19:79–82.
16. Ishikura N, Kawakami S, Yoshida J, Shimada K. Vascular supply of the subcutaneous pedicle of Nagata’s method in microtia reconstruction. Br J Plast Surg. 2004;57:780–784.
17. Frenzel H, Wollenberg B, Steffen A, Nitsch SM. In vivo perfusion analysis of normal and dysplastic ears and its implication on total auricular reconstruction. J Plast Reconstr Aesthet Surg. 2008;61(Suppl 1):S21–S28.
18. Wang WS, Yan DM, Chen JY, Zhang D, Shao Y, Peng WH. Clinical efficacy of a modified Nagata method that retains the fascia pedicle of the mastoid skin flap in auricular reconstruction of Chinese microtia patients. Plast Reconstr Surg. 2016;137:977–979.
19. Nagata S. Total auricular reconstruction with a three-dimensional costal cartilage framework. Ann Chir Plast Esthet. 1995;40:371–399; discussion 399.
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