Design and preliminary testing of a novel skin expander for total ear reconstruction in a rabbit model

BackgroundEar reconstruction is one of the most complicated and challenging techniques in plastic surgery because of the histologic and anatomic properties of the ear. Success depends on fitting the auriform cartilage scaffold into the overlying skin, but current approaches can just give results that are not lifelike and can lead to complications.Materials and methodsA novel double-capsule, double-valve plastic ear expander was designed and implanted subcutaneously on either side of the dorsum of six New Zealand white rabbits (two expanders per rabbit). The outer capsule was expanded by injecting approximately 120 mL of physiological saline, then withdrawing the liquid on two occasions. Next, the ear-shaped inner capsule was filled with high-hardness plaster, and the external capsule was emptied such that the expanded skin flap and external capsule responded to the negative pressure and closed over the ear-shaped inner capsule. As a result, the skin flap adopted an ear shape. The ear expander was left in place for 4 wk, removed with the help of a mini-incision, and stripped of its fibrous capsule. To simulate human ear reconstruction, the expander was replaced with an auriform silicone prosthesis, and the effects of auricular reconstruction were observed dynamically.ResultsAll 12 skin flaps maintained abundant blood supply, created a clear outline of the ear framework, and produced a lifelike result. No complications were observed during the 4-wk observation period.ConclusionsThe expanded skin flaps described here can mold to the desired contours and appear lifelike, as well as maintain abundant blood supply. This may provide a simpler approach to total ear reconstruction that reduces risk of complications.