You are in: eMedicine Specialties > Dermatology > SURGICAL Ear ReconstructionArticle Last Updated: Feb 6, 2007AUTHOR AND EDITOR INFORMATIONSection 1 of 9
  Author: Ken K Lee, MD, Associate Professor, Departments of Dermatology, Surgery, and Otolaryngology-Head and Neck Surgery, Director, Dermatologic and Laser Surgery, Oregon Health and Science University Ken K Lee is a member of the following medical societies: American Academy of Dermatology, American College of Mohs Micrographic Surgery and Cutaneous Oncology, and American Society for Dermatologic Surgery Editors: Shobana Sood, MD, Assistant Professor, Department of Dermatology, University of Pennsylvania Hospital; David F Butler, MD, Professor of Dermatology, Texas A&M University College of Medicine; Director, Division of Dermatology, Scott and White Clinic; Director Dermatology Residency Training Program, Scott and White Clinic; John G Albertini, MD, Consulting Staff, Dermatologic Surgery, The Skin Surgery Center; Catherine Quirk, MD, Clinical Assistant Professor, Department of Dermatology, Brown University; Dirk M Elston, MD, Director, Department of Dermatology, Geisinger Medical Center Author and Editor Disclosure Synonyms and related keywords: helical defects, helix defects, primary linear repair, wedge excision repair, chondrocutaneous advancement flap, banner transposition flap, bilobed flap, O to T advancement flap, anterior surface defects, preauricular sulcus defects, postauricular sulcus defects, lobule defects, skin cancer excision, defects on the ear, skin cancer INTRODUCTIONSection 2 of 9
  Reconstruction of the ear can be a complex process. The 3-dimensional nature of the ear with its many curves, peaks, and valleys demand the utmost attention to detail. Yet, as challenging as it may seem, reconstruction of the ear can be made easier and predictable if one understands the surgical principles and anatomy. The techniques discussed in this article address defects that result from skin cancer excision. More than 1 million cases of basal cell carcinoma, squamous cell carcinoma, and malignant melanoma occur per year in the United States (Miller, 1994). A significant portion of these malignancies arise on the ear because of its exposure to the sun. All areas of the external ear are at risk for skin cancer, and compared with other cancers, these tend to be more aggressive with higher recurrence rates. Given this setting, the defects on the ear can be relatively large. INDICATIONSSection 3 of 9
Reconstruction of the ear is indicated when a defect is present after skin cancer extirpation. The reconstruction methods discussed in this article all follow the principles of Mohs micrographic surgery. Certain small defects may not need reconstruction and can heal by second intention. This concept is also discussed below. RELEVANT ANATOMYSection 4 of 9
The external ear is composed of skin and cartilage with the supporting nerves and blood vessels. The auricular cartilage provides a framework for the entire ear except the lobule. The tightly adherent skin extending from the preauricular sulcus to the helix produces distinct topographical landmarks on the anterior surface of the ear that are important in understanding and describing the ear (see Image 1). The concavities include the triangular fossa, the scapha, the cymba, and the cavum of the concha. The helix, the antihelix, the tragus, and the antitragus form the convexities. The skin on the posterior (medial) aspect of the ear that extends to the postauricular sulcus is less adherent to the underlying cartilage (see Image 2). A well-proportioned ear is 50-60% as wide as it is high. The ear is positioned one ear length from the lateral orbital rim, and the top of the ear is level with the eyebrow and tilted back by 20° (Tolleth, 1978). The auriculotemporal nerve, a branch of cranial nerve V3 innervates the superior aspect of the anterior surface of the ear. The lesser occipital nerve and the great auricular nerve are both derived from C2 and C3. The lesser occipital nerve innervates the superior aspect of the posterior surface. The great auricular nerve innervates the lower portion of both surfaces. The vagus nerve supplies the concha. The ear is well vascularized, an important feature because most flaps are based on a random blood supply. The superficial temporal artery and the posterior auricular artery are branches of the external carotid artery and supply the anterior and posterior surfaces, respectively (Salasche, 1988). Because of the rich blood supply and collateralization, anesthetics that contain epinephrine can be used safely. CONTRAINDICATIONSSection 5 of 9
Reconstruction of the ear has relatively few contraindications. If the patient can tolerate the initial Mohs micrographic surgery, they can usually tolerate the subsequent reconstruction as well, although the complexity of the reconstruction may need to be tailored to the patient's medical state. In patients whose medical condition precludes surgery, other treatment options, such as irradiation, should be considered. The patient's medical history should be assessed prior to surgery. Aspirin and warfarin increase the risk of intraoperative and postoperative bleeding complications. The use of these medications is not an absolute contraindication for skin surgery, but stopping these treatments prior to surgery is ideal, if possible. TREATMENTSection 6 of 9
Surgical TherapyFlaps, grafts, and primary linear closures can be used in reconstruction of the ear. Healing by second intention is also a valuable tool. The reconstruction technique best suited for a given defect is determined by the size and location of the defect. The goal of reconstruction is to restore the shape, size, and alignment of the ear. An important principle in ear reconstruction is that the entire anterior surfaces of both ears cannot be viewed simultaneously. Therefore, reconstructing the ear so that it is not distorted or deformed is important, but one ear does not have to exactly match the contralateral ear in terms of its size and appearance. The ear also has a functional importance for many patients as a supporting structure for eyeglasses. The defects addressed below can occur as a result of Mohs micrographic surgery to treat skin cancers. The reconstructions are categorized on the basis of the anatomic location of the defect. The regions are divided into the helix, the anterior surface, the posterior surface (preauricular sulcus and postauricular sulcus), and the lobule. Helical DefectsThe contour and rigidity of the helix is due to the underlying shape and curvature of the auricular cartilage. The helix arises from the helical root and curves in a semicircular fashion upward then downward to the lobule. The lobule does not contain cartilage. Maintaining the shape and contour of the helix is paramount in recreating a normal-appearing ear. Even a subtle deviation from the normal curvature or a disruption in the contour makes the ear appear abnormal. Primary linear repair Small helical defects with intact cartilage can be repaired with linear layered closures (see Image 3). However, this type of closure does narrow the width of the helix. To better blend this narrowing, the length of the closure may need to be lengthened to taper this effect. Even in larger defects in which cartilage is missing, primary linear closures can be used. In situations in which the patient's condition precludes a complicated closure, the exposed cartilage can be trimmed and the anterior and posterior skin simply reapproximated (oversewed). Wedge excision repair Defects on most aspects of the helix can be repaired with a wedge excision (see Image 4). The principle behind the wedge closure is the conversion of the defect into a full-thickness (anterior skin, cartilage, posterior skin) triangular wedge. Ideally, the inner corner of the wedge is 30° to minimize the formation of a dog ear. For larger defects, full-thickness Burrow triangles can be superiorly and inferiorly excised to form a star (Brent, 1977) (see Image 5). The wedge is repaired by carefully reapproximating each layer (ie, posterior skin, cartilage, anterior skin). The helix must be meticulously realigned to prevent notching. The use of vertical mattress sutures on the helix helps prevent this problem. The ear wedge always makes the ear smaller; therefore, the size of the defect is the limiting factor. With defects smaller than 1.5 cm, the shape and appearance of the ear is preserved (Quatela, 1995). With larger defects, the likelihood of distortion and deformity increases. Larger ears can tolerate larger wedge excisions and vice versa. Chondrocutaneous advancement flap procedure Defects confined to the helix with or without a cartilage defect can be repaired with the chondrocutaneous advancement flap, or Antia-Buch chondrocutaneous advancement flap. This flap is used for moderate-sized defects on the helical rim. The skin of the helix and the underlying cartilage are either unilaterally or bilaterally advanced. The flap has 2 variations. In the first, the flap can be of full thickness and detached on both the anterior and posterior surfaces of the helix. This construction allows for maximal extension of the flap, although the flap pedicle is relatively narrow. (In the second, the flap can be designed with the posterior skin intact, leaving a broader flap base as Antia and Buch originally describe (Antia, 1967). The entire posterior skin is undermined to elevate the flap. Then, the flap is advanced with a dog ear that is removed posteriorly (see Images 6-7). The helix must be meticulously realigned. In either variation of the flap, a Burrow triangle may need to be excised if the defect is large. Additional length can be gained by using a V-to-Y advancement of the helical root (Brent, 1997). The ear is smaller than it is at the baseline. However, it is not as small as it would be with a wedge excision closure because of the stretch provided by the flap and smaller sacrifice of the cartilage. The use of the chondrocutaneous advancement flap is usually limited to defects 2.5 cm or smaller. Banner transposition flap procedure Defects on the superior aspect of the helix are ideal for repair with the banner transposition flap. Originally described with use of the postauricular skin, the loose preauricular skin can also serve as the donor site for the flap (see Image 8) (Crikelair, 1956; Lawson, 1984). The base of the flap is superior and contiguous with the defect; this construction allows for the flap to be draped onto the defect. To preserve a wide flap base, the posterior dog ear must be removed with an incision away from the base. This flap can be used only for defects of the skin or for defects of both the skin and cartilage. If a large portion of the cartilage is missing, a cartilage graft from the contralateral ear can be used. For more superior defects not involving the region of the helical root and not contiguous with the preauricular skin, the transposition flap can be converted to a tubed pedicle flap to cross over the intact intervening skin. The pedicle remains attached for approximately 3 weeks while the flap develops an adequate blood supply. The pedicle is then sectioned, and the flap is trimmed to fit the defect. Bilobed flap procedure Defects on the superior and mid helix can be repaired with a bilobed flap. Ideally, the cartilage should be intact, but the flap has enough bulk to offset a small cartilage defect. The loose postauricular skin is easily undermined and serves as the donor site for this flap. The classic bilobed flap has a base that is 180°, with 90° between each lobe. This flap can be modified to decrease the angles between the lobes to reduce the movement and the size of the dog ears (see Images 9-10) (Zitelli, 1989). The pivot point of the flap must be understood to enable correct measurement of the appropriate length and width of the flap. Defects as large as 2 cm can be repaired with a minimal reduction in the size of the ear. O-to-T advancement The O-to-T advancement flap is useful for defects that are predominantly on the posterior aspect of the helix. The flap allows for the repair of the helical contour without a significant reduction in the size of the ear or narrowing of the helix. It can be used in areas where the donor skin is insufficient for a bilobed flap. A longitudinal incision is made along the helix, and the flap is lifted off of the skin on the posterior part of the ear. The flap is advanced together to cover the defect (see Images 11-12). Anterior Surface DefectsThe triangular fossa, the scapha, the antihelix, and the concha are the regions inside the helical rim. Defects in these regions must be assessed for involvement of only the skin, the skin and perichondrium, or the skin and cartilage. Skin grafts are useful in covering a wide variety of ear defects. If the perichondrium is present, a full-thickness skin graft can be applied. Depending on the size of the defect, the common donor sites are the contralateral postauricular sulcus or the supraclavicular skin. Split-thickness skin grafts (STSGs) can also be used, although the color and texture match may not be as good as with other methods (Wines, 2001). STSGs have an advantage in that they can survive even if the entire perichondrium is not intact. If no perichondrium is present, the cartilage can be excised to reveal the posterior skin of the ear. For most defects within an intact helix, enough structural support is present even without the cartilage. A graft can be placed on this vascular bed (see Image 13). Grafts placed in the concha should be generously sized to compensate for the profound concavity. Small defects can heal by second intention whether or not the perichondrium is intact. If the perichondrium is absent, small holes should be made through the cartilage to facilitate healing from the posterior skin (see Image 14). Concave or flat surfaces are ideal for second intention healing because the resultant scar is usually slightly depressed (see Image 15). If the defect extends into the external auditory canal, an STSG should be placed to prevent strictures of the canal. Preauricular Sulcus DefectsDefects in this region often extend onto the tragus and the helical root. Because of the laxity of the cheek skin, a flap can be raised and advanced posteriorly to close the defect (see Image 16). Loss of the tragus and subtle loss of the helical root are usually unnoticeable from a frontal view. The resultant scar blends nicely into the face-lift line. Postauricular Sulcus DefectsSkin cancers in this region are relatively large because they can go unnoticed for long periods. Defects on the posterior surface can be closed with grafts, flaps, or primary closures as described above. Many cancers arise in the sulcus. The defect straddles the sulcus, resulting in premastoid and posterior ear components that are similar in size and shape. STSGs are commonly used to cover large defects, but they may result in the anterior protrusion of the ear. A simpler repair technique is to pin the ear back, adjoining both sides of the defect in a fashion similar to closing a postauricular skin graft donor site. Large defects encompassing almost the entire posterior surface of the ear can be closed in this manner (see Images 17-18). A single layer of modified vertical mattress sutures (3-0 Vicryl) is used to close the entire defect. The modification entails grabbing the base of the sulcus with the suture to close the dead space. The sutures are left untied until all the vertical mattress sutures are in place (see Image 19). The sutures are removed in 2 weeks. Although the postauricular sulcus becomes narrower than the contralateral ear, it typically does not appear asymmetric from either the frontal or the posterior views. If tacking back of the ear is too excessive for the patient, the wound edges can be pulled slightly apart at the time of suture removal and allowed to heal by secondary intention. Split bilobed flaps have been used to repair composite posterior auricular and mastoid defects. Lobular DefectsDefects of the lobule and lower helix can be repaired with either a primary linear closure for partial-thickness defects or wedge excision for full-thickness defects. Defects involving as much as 50% of the lobule can be repaired in this fashion (see Image 20). To prevent notching or separation, wound eversion is important. OUTCOME AND PROGNOSISSection 7 of 9
Given the great number of skin cancers on the ear, a tremendous variety of defects can result from their treatment. A systematic practical approach must be adopted to meet the challenge of these defects. By categorizing the defects by their size and location, these defects can be reproducibly repaired to restore the symmetry, aesthetics, and function of the ear. MULTIMEDIASection 8 of 9
REFERENCESSection 9 of 9
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