Reconstruction of the microtic ear represents one of the most demanding challenges in reconstructive surgery. In this review the two most commonly used techniques for ear reconstruction, the Brent and Nagata techniques, are addressed in detail. Unique to this endeavor, the originator of each technique has been allowed to submit representative case material and to address the pros and cons of the other's technique. What follows is a detailed, insightful overview of microtia reconstruction, as a state of the art. The review then details commonly encountered problems in ear reconstruction and pertinent technical points. Finally, a glimpse into the future is offered with an accounting of the advances made in tissue engineering as this technology applies to auricular reconstruction.

Auricular reconstruction for microtia: Part II. Surgical techniques.

This article presents an improved two-flap method for microtia reconstruction. In the first stage of this method, a tissue expander is inserted in the mastoid region through a subfascial pocket, after which the overlying fascia and skin are expanded simultaneously with saline infusion for about 5 months. In the second stage, the expanded fascial and skin layers are split and prepared as anteriorly based skin and fascial flaps defined by their vascularity. An erect, three-dimensional, contour-accentuated ear framework fabricated with autogenous rib cartilage is inserted between the two flaps. The anteroauricular surface of the framework is draped with the thin, expanded skin, and the postauricular surface is draped with the thin, expanded fascia and overlying grafted skin. In the third stage, remnant auricular cartilage is removed and the crus helicis, tragus, intertragic notch, conchal floor, and a hollow mimicking the external auditory meatus are shaped. In this study, 146 microtias were reconstructed consecutively using the improved two-flap method. The final results were promising--major complications were minimal and most patients showed consistently favorable aesthetic results. This method married a two-flap procedure with a gradual tissue expansion, conveniently exploiting the advantages of both methods, but without the disadvantages.

Subfascial expansion and expanded two-flap method for microtia reconstruction.

SUMMARY The reconstruction of microtia continues to represent one of the more challenging plastic surgery procedures. The limitations of the reconstruction are partly inherent in the soft-tissue deficiencies present in increasing degrees from large conchal remnant microtia, to lobular microtia, to the displaced remnant in auricular dystopia, and partly because of the high level of technical expertise required. After a brief review of the history of ear reconstruction in general and microtia specifically, issues related to the transition in the popularity from techniques involving three or more stages (Tanzer and Brent) to the current popularity of two-stage procedures (Nagata, Firmin, and Park) are discussed in detail. Each of the popular procedures is viewed in relation to timing of the reconstruction, procedure planning, and how both the soft tissues and framework construction are handled, in each of the stages. The most significant differences include whether the autogenous cartilage framework is constructed with or without the tragal construct (for the lobular-type microtia), whether or not the lobule is rotated in the first-stage reconstruction, whether an additional cartilage block is placed behind the framework for added ear projection, and how that added block is covered (choice of fascia flap and skin graft). Each of the techniques has to be varied in reconstruction of auricular dystopia in light of the associated skeletal and soft-tissue hypoplasia. In this article, the author demonstrates that although there may be significant advantages to the two-stage reconstructions of Nagata and Firmin, some may feel that the larger amount of cartilage harvested, the later optimal age for beginning the reconstruction, the additional scalp scars engendered by using the temporoparietal fascia flap in the second-stage elevation of the framework, and even the exchange of lobule tissue (and ability to later pierce ears) to obtain better coverage of the concha and tragus are unacceptable. Having gained experience with each of the varied approaches and having modified them when unusual variations in deformities have required it, the author discusses his current preferences. Clearly, this author feels that there may be significant advantages to delaying the reconstruction to age 10 years or older, yet experience gained over the past 25 years would seem to indicate that as in all other aspects of plastic and reconstructive surgery one must never be wed to a single approach, and experience and flexibility are essential in obtaining the optimal outcome in all variations of the deformity.

Reconstruction of microtia.

Statement of problem. Although surgical reconstruction is the treatment of choice for auricular deformities that result from hemifacial microsomia, the implant-retained auricular prosthesis must be considered when surgical reconstruction is not possible. The competent and successful practitioner should be knowledgeable of the nature of this congenital disease. Purpose. This article reviewed the first and second branchial syndrome, treatment approaches, and potential advances in surgical and prosthetic rehabilitation for patients with hemifacial microsomia. Conclusion. Advantages and disadvantages of autogenous and alloplastic ear reconstructions are discussed. New research initiatives, such as tissue engineering and fabrication of auricular prosthesis by CAD/CAM, offer the potential for improved treatment for the future treatment of hemifacial microsomia. (J Prosthet Dent 1999;82:197-204.)

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Hemifacial microsomia and treatment options for auricular replacement: A review of the literature

Recent advances in regenerative medicine place us in a unique position to improve the quality of engineered tissue. We use auricular cartilage as an exemplar to illustrate how the use of tissue-specific adult stem cells, assembly through additive manufacturing and improved understanding of postnatal tissue maturation will allow us to more accurately replicate native tissue anisotropy. This review highlights the limitations of autologous auricular reconstruction, including donor site morbidity, technical considerations and long-term complications. Current tissue-engineered auricular constructs implanted into immune-competent animal models have been observed to undergo inflammation, fibrosis, foreign body reaction, calcification and degradation. Combining biomimetic regenerative medicine strategies will allow us to improve tissue-engineered auricular cartilage with respect to biochemical composition and functionality, as well as microstructural organization and overall shape. Creating functional and durable tissue has the potential to shift the paradigm in reconstructive surgery by obviating the need for donor sites.

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Combining regenerative medicine strategies to provide durable reconstructive options: auricular cartilage tissue engineering.

A single-stage two-flap method of total ear reconstruction in congenital microtia is reported. This method was derived from the one-stage reconstruction described by Song and Song. Two flaps defined by vascular basis were elevated on the mastoid area: the superficial skin flap supplied mainly by subcutaneous pedicled arteriole perforators from the posterior auricular artery and the deeper axial-pattern fascial flap including the posterior auricular artery itself. The ear framework, exaggeratedly carved using autologous rib cartilage, could be inserted easily between the two flaps, simultaneously producing the auriculocephalic angle and the conchal wall. Intraoperative expansion of the skin flap and postoperative external ear molding also were performed to create aesthetically pleasing ears.

Yang Woo Kim

Papers

A single-stage two-flap method of total ear reconstruction