Each defect repair begins with reverticalization of the wound edges and sharp débridement of any fibrinous tissue or debris in the base of the defect. This mixture is injected subdermally at the site of the defect and the graft donor site. A 1:1 mixture of 0.25% Marcaine (Hospira, Inc., Lake Forest, Ill.) with 1% lidocaine with epinephrine (mixed 1:1000 in 30 cc of lidocaine) is used for local anesthesia, vasoconstriction, and postoperative analgesia. Procedures are performed under local anesthesia with or without intravenous sedation in an operating room setting. The unique nature of the lower third skin, which is often thick and richly populated with sebaceous glands, complicates reconstructions, often rendering the skin stiff and difficult to rotate and form into local flaps. Importantly, the ala and tip are biconvex structures, and maintaining and restoring the contour of these structures is essential to aesthetic nasal reconstruction. The lower third of the nose is classically composed of six subunits: bilateral ala and soft triangles, the central tip, and columella ( Baker & Swanson, 1995) ( Fig. Any distortion of the alar rim or obliteration of the nasolabial groove is exceedingly noticeable to the naked eye and difficult, if not impossible, to correct secondarily. The boundaries defining the lower third of the nose include the alar rims inferiorly, the nasolabial grooves laterally, and the alar groove, which forms the junction with the upper two-thirds of the nose ( Collins & Farber, 1984 Leibovitch et al., 2006). There is a common reluctance to advance skin from the nasal sidewall to reconstruct lower third defects, as this destroys the alar groove, an aesthetic subunit that is very difficult to reconstruct. In addition, the final result is inherently unpredictable because of its tendency to pincushion. The inherent design flaw of the bilobed flap violates a second or third aesthetic unit and often completely distorts the alar groove. The use of bilobed flaps from the upper third of the nose to recreate defects on the lower third commonly disappoints for two reasons. Larger defects could be easily and reliably reconstructed with the well-established algorithms (i.e., nasolabial or forehead flap reconstruction). The evolution of the demonstrated skin grafting techniques started with the recognition of the frustrating paradox in reconstructing small defects of the lower third. Such defects can be successfully and reliably treated with well-applied full-thickness skin grafting from the preauricular or more preferential forehead donor site. These defects rarely encompass greater than 50 percent of aesthetic subunits and are best treated as defect-only reconstructions ( Dimitropolous et al., 2005). In many cases of lower third nasal reconstruction, particularly those arising from excision of neoplasms by means of Mohs’ micrographic surgery, the defects are shallow and measure less than 1 cm in diameter. Likewise, the misapplication of skin grafts to large or deep lower third defects often yields a depressed patchwork with unsuitable results. Local flaps applied for these defects often result in violation of aesthetic subunits, worsening of the defect by alar notching, and frequent or unpredictable pincushioning. Paradoxically, acceptable results are more difficult to achieve with smaller defects, most notably those smaller than 1 cm. These techniques require multiple stages and allow for the replacement of cartilage and lining if missing. ![]() The lower third nasal defects or defects larger than 1.5 cm in diameter can be reliably reconstructed and repaired with nasolabial or forehead flaps using either a subunit or defect-only reconstruction ( Barton, 1981). Specific flap algorithms are available for reconstruction of full-subunit alar or full-subunit tip defects ( Hill, 1987). ![]() The unique character of the lower third of the nose, with its interwoven concavities, convexities, and varying skin thicknesses, exacerbates the difficult reconstruction of this region. Lower third nasal defects present a special challenge to reconstructive surgeons.
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