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Auricular reconstruction
Dermatol Clin 23 (2005) 23 – 41
Auricular reconstruction David G. Brodland, MD Departments of Dermatology and Otolaryngology, University of Pittsburgh, South Hills Medical Building, 575 Coal Valley Road, Suite 360, Pittsburgh, PA 15025, USA
The auricle is a complex-looking structure, with undulating topography and structural characteristics ranging from firm, rigid cartilage to the soft, spongy, and elastic earlobe. With the two primary goals of reconstruction being restoration of form and function, these complex anatomic features make the former a challenge. Yet the function of the auricle in humans is relatively simple and basic. The main functional consideration during reconstruction of the auricle is maintaining the patency of the external auditory canal (EAC). There are key anatomic features of the ear that make reconstruction of the auricle unique and that can be taken advantage of by the surgeon to optimize its reconstruction. These features include the following: a rich blood supply; a complex topography, which is highly variable from person to person; a relatively inconspicuous lateral location with limited visibility on frontal view; and a very firm infrastructure of most of the auricle [1 – 3]. These aspects affect reconstruction of the ear and profoundly affect the skill set required for success. The goals of auricular reconstruction can be categorized into primary and secondary goals (Box 1). There are three primary goals: (1) maintaining function through patency of the auditory canal, (2) maintaining the overall anterior profile, and (3) maintaining the lateral profile. The anterior profile includes the modest projection from the side of the head, which should be slightly greater superiorly than inferiorly. The helical rim and the helical groove are typically the most visible aspects on frontal view. The lateral profile is characterized by the nautilus-like shape, with smooth curvature at the perimeter and the
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lobule of the ear, which is approximately one third of the vertical height of the remainder of the ear. If the final result of the reconstruction achieves these three primary goals, most surgeons would find the results very satisfactory. Secondary goals of auricular reconstruction include the preservation or recreation of the ear’s complex topography, camouflage of the scar, and maintenance of the size of the ear. Although these goals are not inconsequential, for various reasons they are all somewhat less critical than the primary goals of reconstruction. The maintenance of the anterior and lateral profile have more to do with the method of reconstruction whereas maintaining patency of the EAC is more an issue of wound management and, in particular, the prevention of scar contraction. The assessment of the nature of the wound involving the EAC is the critical factor in deciding how to manage wounds in this area. Typically, if the cartilage of the EAC is intact and the wound does not involve the entire circumference of the EAC wall, then second-intention healing is rarely complicated by constriction of the EAC. In the case of a circumferential wound within the EAC or significant loss of portions or all of its cartilaginous wall, an effort to decrease or eliminate scar contraction is advisable. The camouflage of the scars of reconstruction is secondary mainly because most scars, unless hypertrophic or keloidal, blend in inconspicuously. The complex topography also helps in making scars inconspicuous. Maintaining the size of the ears is a secondary issue in reconstruction for several reasons. Because of the lateral location of the ears, size differences between the two ears are typically inconspicuous. Size changes are most evident on lateral view and
0733-8635/05/$ – see front matter D 2005 Elsevier Inc. All rights reserved. doi:10.1016/j.det.2004.08.008
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Box 1. Primary and secondary goals in auricular reconstruction Primary 1. Function (patent auditory canal) 2. Maintain anterior profile 3. Maintain lateral profile Secondary 1. Preservation and restoration of topography 2. Camouflage scar 3. Maintain size of ear
would require a concerted effort to compare the size of one ear with the other. As long as the lateral, nautilus-like profile of the helix is maintained, minor size changes do not draw attention to the ear. Reconstruction of the ear is simplified by recognizing its distinct anatomic zones. Depending on the location of the defect and the zone or zones involved, reconstruction options vary greatly. The three basic zones of the ear include the anterior ear, the posterior ear, and the helical ear. The anterior ear includes the conchal bowl, the antihelix, and the crus of the antihelix. The helical zone of the ear can be broken up into the superior helix, the midhelix, and the inferior helix/ lobule. Each of these zones is structurally unique and is reconstructed in an equally unique fashion.
Posterior ear The choice of reconstruction for the posterior ear is closely related to functional concerns. Most wounds that occupy less than half of the total surface of the posterior ear and sometimes even greater than half of the posterior ear can heal by second intention without significant distortion of the anterior or lateral profile of the ear (Fig. 1). When the cartilaginous structure of the ear has been compromised, however, greater caution is necessary with regard to secondintention healing and maintaining the profiles of the ear. Another functional issue arises when the defect involves either a substantial portion of the posterior ear or extends into the postauricular sulcus and onto the skin overlying the mastoid bone. If these wounds are allowed to heal by second intention, sometimes the ear is effectively ‘‘pinned back,’’ which can be uncomfortable and make eyeglasses fit improperly. In the event that healing by second intention is not feasible, the most commonly used reconstructive option is grafting. Both full-thickness skin grafts and split-thickness skin grafts are useful, but there are several features of split-thickness grafts that make them a serious consideration for the postauricular ear. A split-thickness skin graft has a low nutritional requirement, making successful engraftment very likely. Because the posterior ear is not highly visible, the aesthetic disadvantages of split-thickness skin grafts are not as great an issue. Even so, the skin on the posterior ear is naturally very thin and is usually well simulated in appearance by split-thickness skin grafts. There are many potential donor areas for split-thickness skin grafts, but the skin overlying
Fig. 1. (A) Superficial defect of posterior ear. (B) Results at 1-year follow-up.
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Fig. 2. (A) Defect of the posterior ear extending into the postauricular sulcus. (B) Side-to-side closure using buried horizontal mattress sutures.
the mastoid process is a convenient and effective donor site for split-thickness skin grafts up to 4 cm. This donor site tends to heal very quickly not only because wounds on the head do so by nature but also because of the high density of adnexal structure contributing to the rapid re-epithelialization of the donor site. Smaller defects located close to or within the postauricular sulcus can be conveniently closed with-
out functional or aesthetic consequences with dermal horizontal mattress sutures drawing the wound edges closed in a direction parallel to the sulcus (Fig. 2). Small Burow’s triangles can be excised superiorly and inferiorly. Epidermal sutures are not usually necessary, and often it is preferable not to undermine extensively or at all to avoid tenting across the sulcus. This technique is usually limited to wounds smaller than 2 cm in horizontal diameter.
Fig. 3. (A) Large defect of the posterior ear and retroauricular skin. (B) Near-total loss of cartilage results in near-complete loss of the ear’s rigid structure. (C) Posterior view of defect showing near-total loss of cartilage. (D) The remnant of the ear is inset and tacked to the retroauricular defect, providing it with rigid backing and reconstituting its lateral profile.
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An uncommon situation is the loss of most of the cartilage having the anterior surface of the ear intact but without any rigid structure. In such cases, it may be impractical to obtain cartilage grafts large enough to reconstitute the auricular infrastructure. A reasonable alternative is to inset the ear onto the rigid retroauricular surface using this rigid structure in lieu of cartilage (Fig. 3). There is an effect on the anterior profile of the ear because the remnant of the ear is pinned back. It therefore will project less from the side of the ear. It does maintain both function and lateral profile, however, which may be a reasonable compromise in a difficult situation. There are other flaps that can be used to reconstruct the posterior ear and, in some situations, may be absolutely necessary for the posterior ear. In the current author’s experience, however, simpler is usually better and very effective. Therefore, healing by second intention, grafting, or primary closure are the most commonly used reconstruction methods for defects in this anatomic zone.
Anterior ear Reconstruction of the anterior ear is guided by the same principles as other areas of the ear—that is, to maintain form and function of the ear. The first and foremost consideration of most smaller wounds not involving a significant amount of cartilage is secondintention healing (Fig. 4). The texture and color of the skin combined with the rigid infrastructure make deformation an unlikely event. With the exception of large wounds within the EAC, the alteration of function is also a rare complication if wounds are allowed to heal by second intention. Factors that may favor reconstruction of an anterior ear defect include large defects, which, if allowed to heal by second intention, would deform
the auricle or affect the patency of the EAC. Other factors include large wounds with large amounts of exposed cartilage, which may result in a chondritis secondary to exposure and desiccation. Another relative indication for wound closure is a defect that would be difficult for the patient to take care of if allowed to heal by second intention, either because the patient is unable to effectively cleanse and rebandage the wound or the patient has no one available to assist him or her in wound care. Some patients who wear hearing aids benefit from the more rapid healing afforded by reconstruction, which allows them to wear their hearing aid more quickly and comfortably following surgery. Because of the naturally thin skin typically found on the anterior ear, the split-thickness skin graft is often the easiest and most effective way of reconstructing this portion of the ear (Fig. 5). The nutritional requirements of a split-thickness graft are less than a full-thickness graft, making it ideal in wounds extending to the perichondrium. A fullthickness skin graft is often the preferred closure in a well-vascularized wound base and in patients with thick, sebaceous skin. Regardless of the type of graft used to reconstruct the anterior ear, by definition, a second wound is being created in the harvesting of the graft. Therefore, it is wise to select the donor site judiciously so that healing is made as convenient as possible for the patient. Furthermore, the selection of graft type and donor site should be made with consideration of what the optimal thickness and skin characteristics would be for that patient. Some patients’ anterior ear skin is quite thick and others’ anterior ear skin is extremely thin. The recognition of these characteristics can direct the surgeon’s choice of donor site. Often, a donor site in the periauricular region is most convenient and optimal in terms of thickness and skin consistency. An excellent site for a split-thick-
Fig. 4. (A) Defect of the anterior ear. (B) Results 3 months after second-intention healing.
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Fig. 5. (A) Large defect of the anterior ear. (B) Reconstruction with split-thickness skin graft harvested from the retroauricular skin over the mastoid process.
ness graft of small- to moderate-sized defects is the skin overlying the mastoid bone. The hair in this area can be shaved, and the split-thickness graft can be harvested by either freehand dermaplaning with a scalpel or with one of the split-thickness graftharvesting tools, such as the Goulian skin knife and guards (Weck, Durham, North Carolina). As described earlier, the re-epithelialization time of the donor site is remarkably fast. Further, any resulting scar is camouflaged by the regrowth of hair, which is unaltered by the superficial harvesting of the graft. Alternatively, the more traditional split-thickness donor sites can be used, including the anterior and lateral thigh. Full-thickness skin grafts are most conveniently harvested from the retroauricular skin. Depending on the size of the ear, 2- to 3-cm grafts can be obtained from this area. A template is made of the defect and used for incising the graft by placing approximately one half of the template on the posterior surface of the ear and the other half on the retroauricular skin. The donor site can often be closed by horizontal dermal sutures placed across the wound, such that the wound edge on the posterior ear is sutured to the wound edge of the retroauricular skin. Care must be taken to avoid pinning back the ear. Full-thickness skin grafts from other donor sites can be used. Many of the other traditional donor sites yield grafts that are too thick to match the normal skin characteristics of the anterior ear, however. For example, grafts from the supraclavicular fossa are often too thick to satisfactorily match the anterior ear. Extensive defects of the EAC may require reconstruction to preserve the patency of the canal. Wounds involving most or all of the circumference of the canal or wounds with extensive cartilage loss
require reconstructive intervention because contraction can threaten canal patency. Perhaps the easiest and most effective way of reducing contraction within the ear canal is with a skin graft. Thin full-thickness skin grafts may be effective and are reported to decrease scar contractions better than split-thickness skin grafts. Because of the small caliber of the EAC, however, a splitthickness skin graft is highly effective and less likely to cause a narrowing of the canal from edema of the graft. Sometimes full-thickness skin grafts swell or thicken in the months following engraftment, reducing the overall caliber of the canal. Split-thickness skin grafts are not only thinner and less likely to thicken and swell, but they also have a lower nutritional requirement, making successful engraftment more likely (Fig. 6). Some flaps have been reported for the reconstitution of the EAC; however, they are at greater risk for postoperative edema and inadvertent occlusion of the otherwise patent canal. A helpful technique for the nonhelical posterior surface of the ear and anterior surface of the ear when the defect has a significant amount of exposed cartilage stripped of its perichondrium is full-thickness perforation of the cartilage. This technique is most conveniently performed with 3-mm or 4-mm punch holes created by a skin punch tool. The relatively avascular cartilage, when stripped of its perichondrium, will not support skin grafts. The perforation through to the opposite side of the ear creates portals through which the vascular supply from the subcutaneous tissue on the opposite side of the ear can be made a source of oxygen and nutrients to support the graft (Fig. 7). Likewise, in defects that are 1.5 to 2 cm without perichondrium that are being allowed to heal by second intention, perforation can
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Fig. 6. (A) Large defect involving conchal bowl with the wound extending deep into the EAC. (B) Reconstruction of the preauricular portion of the defect with a flap and the conchal bowl and EAC with a split-thickness skin graft. (C) Three-month postoperative result with excellent maintenance of EAC patency.
greatly speed the rate of healing because of granulation tissue growing through the perforations from the opposite side of the ear. Typically, more perforations are necessary for grafting than for secondintention healing, with no more than approximately
5 mm of cartilage intervening between the perforations. To potentiate healing by second intention, one perforation per square centimeter is usually sufficient. Another useful technique in the reconstruction of larger ear defects where enough cartilage has been
Fig. 7. (A) Conchal bowl defect with exposed cartilage stripped of perichondrium. Perforation being made with a punch biopsy tool. (B) Perforation enables granulation tissue from the posterior ear, providing vascular tissue to support rapid re-epithelialization of the wound.
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Fig. 8. (A) Large anterior ear defect. (B) Loss of helical and antihelical cartilage results in severe structural compromise. (C) Cartilage grafts from contralateral ear are used in spoke-and-wheel configuration to reconstitute and maintain the structure of the ear. (D) A split-thickness skin graft is harvested from over the mastoid bone. (E) The split-thickness skin graft is sutured over the cartilage grafts to resurface the wound. (F) Follow-up at 6 months shows excellent preservation of the shape and appearance of the ear.
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excised to impair the structural integrity of the auricle is the use of cartilaginous struts. The ideal wound for this technique is typically one where enough of the auricular cartilage is preserved to maintain the shape of the ear but where there is not enough structural integrity to prevent deformation of the shape with normal contraction of the wound (Fig. 8). These cartilaginous struts can be harvested from the margins of the cartilaginous wound or the contralateral ear. Typically, the strut is 3 to 4 mm in width and measured to be slightly longer than the width of the cartilaginous defect. These struts are then placed across the defect and anchored with sutures into the base of the wound and to both sides of the cartilaginous defect. Grafts or flaps can then be laid over the cartilage. As long as close contact to a vascularized base of the wound is maintained, the cartilaginous strut can be expected to engraft. Split-thickness skin grafts often maintain viability through vascular bridging over the avascular cartilaginous graft. The same principle of using thin strips of cartilage across cartilaginous defects is used with cartilage flaps for auricular reconstruction. Again, the ideal situation for this technique is a defect in which the helix has been preserved and yet lacks sufficient structure to maintain normal shape during scar contraction (Fig. 9). In this situation, a cartilaginous flap can be created by incising a narrow 2- to 3-mm – thick strip of cartilage tangential to the defect, leaving it attached at one end. The cartilage flap can then be carefully bent at a 90° angle and fixated by suturing the flap into the wound base and suturing its distal end into the cartilaginous helical remnant. Graft or flap closure of the cutaneous defect completes the reconstruction. Presumably, the cartilaginous flap remains vascularized, which may ensure its survival. A few defects of the anterior ear require reconstruction with flaps. Flaps are typically reserved for situations in which a vascularized resurfacing of the auricle is needed. These situations include defects in which there is extensive exposure of cartilage that has been stripped of its perichondrium. In addition, defects that require cartilage grafting to reconstitute the structural integrity of the auricle are best resurfaced with a well-vascularized flap. These local flaps are usually based on the retroauricular skin posteriorly or the preauricular skin. The two-stage retroauricular pedicle flap is most often used in defects that involve reconstruction of the helix. It can also be used in defects limited to the anterior surface of the ear but will be described in more detail later. A flap that is frequently described for large defects of the anterior ear is the ‘‘flip-flop flap,’’ also known as the retroauricular pull-through flap. In this flap, a
template is made of the defect on the anterior surface of the ear and used to incise a flap on the retroauricular skin and in the postauricular groove (Fig. 10). This is an island flap with a pedicle based predominantly in the retroauricular groove. The flap is carefully reflected from posterior to anterior, leaving a substantial subcutaneous pedicle anteriorly. If a full-thickness communication to the anterior surface of the ear through the conchal bowl does not already exist, it should be made to deliver the island flap to the anterior ear defect. If cartilage grafting is necessary, it is then sutured into position and the flap is sutured into place over top. If the donor site cannot be closed primarily, it can be partially closed and allowed to heal by second intention or grafted. These flaps are robust because of the excellent vascular supply in and around the ear. This flap is most useful in inhibiting wound contracture that would be deforming to the shape of the ear and in instances when cartilage grafts from the contralateral ear are required to maintain its structural integrity. There may be times when a two-stage pedicle flap using the preauricular skin is useful. In this case, a superiorly based pedicle can be created and non – hair-bearing auricular skin can be imported into the anterior surface of the ear to provide a vascularized resurfacing of a defect. This pedicle is transected 2 to 3 weeks later, and the donor site closed primarily.
Reconstruction of the helix The helix is the structure of the auricle that is most responsible for its normal shape and position. Not only is it the most common location of skin cancers of the ear but it is also the most delicate and easily deformed structure, making it the most challenging aspect of ear reconstruction. The helix is conveniently broken up into three zones: the superior, mid-, and inferior helix. The superior portion is that which is largely horizontally oriented, whereas the inferior helix includes the inferior 1 cm of the helix and the earlobe. The remaining helix is the midhelix. The superior helix is characterized by potential donor skin at the anterior attachment of the ear, the posterior ear, and retroauricular sulcus. The midhelix has a more limited donor pool, which is located on a relatively rigid portion of the ear. This donor pool consists of the helix superiorly and inferiorly and the posterior ear. It is this region that, because of its isolation from substantial donor pools, makes it the most common site for the two-stage retroauricular pedicle flaps. The inferior helix, in contrast, is adjacent to the earlobe, which is very elastic tissue
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Fig. 9. (A) Large posterior ear defect with massive loss of cartilage but preservation of the helical and the conchal bowl cartilage. (B) A cartilage flap is fashioned from the remnant cartilage of the conchal bowl and carefully transposed parallel to the postauricular sulcus and perpendicular to the helix. The flap is affixed by suturing and serves as a supportive spoke between the conchal bowl and helical rim. (C) A full-thickness skin graft is applied to the defect. (D) Immediately following surgery, the previous collapse of the helix is prevented and the lateral profile is maintained. (E) Postoperative result at 3 months, posterior view. (F) Postoperative result at 3 months, lateral view, with excellent preservation of the helix.
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Fig. 11. (A) Postoperative defect of the superior helix. (B) Full-thickness skin graft from the postauricular sulcus sutured into place. (C) Three-month postoperative result.
and as such an ample source of donor skin. Although this elasticity is useful in reconstructing defects superior to the earlobe, the earlobe’s lack of rigid infrastructure results in the biggest challenge of reconstruction of the earlobe, which is maintaining its shape.
Superior helix The most common closures of the superior helix include helical advancement, transposition flaps, and full-thickness skin grafts. Two-stage pedicle flaps may also be useful in large defects of this location. Well-vascularized wounds are often most easily repaired with full-thickness skin grafts harvested
from either the postauricular sulcus or the preauricular skin (Fig. 11). Grafts have the advantage of not creating any distortional countertensions, which can be a problem with flaps. The biggest unknown factor is the degree to which a full-thickness graft will survive. Grafts on the ear are more prone to disruption of vascular inosculation because it is difficult to adequately protect and pad the ear from accidental injury. The graft can be protected and stabilized using tie-over bolster dressing, which can reduce the chance of disruption of the graft and improve the chance of complete survival. Helical advancement flaps are the workhorse flap for the superior and inferior helix. For the superior helix, a sizable donor pool is available at the anterior attachment of the ear (Fig. 12). Typically, a skin flap
Fig. 10. (A) Large defect of the anterior ear with loss of most of the conchal bowl and portions of the antihelical cartilage. (B) Severe compromise of structure of the ear caused by cartilage loss. (C) View of the retroauricular flap and posterior surface of the ear. An incision has been made through the posterior surface of the ear through which the retroauricular flap will be delivered to the anterior surface of the ear. (D) Delivery of the retroauricular skin flap through the posterior ear to the anterior surface of the ear. (E) Flap sutured into place. (F) Six-month postoperative result with satisfactory maintenance of the auricular profile.
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Fig. 12. (A) Defect of the superior helix. (B) Anteriorly based advancement flap reconstruction.
is created by a tangential incision located along the rim of the helix. A second tangential excision is commonly made parallel to the first on the posterior surface of the ear, creating a peninsular skin flap that is based anteriorly at the attachment of the ear to the cheek. This form of advancement flap is known as a double-tangent advancement flap.
An alternative approach is to forgo the second parallel tangential incision and instead remove a Burow’s triangle from the posterior surface of the ear perpendicular to the first tangential incision. The flap is then raised by undermining in the deep subcutaneous tissue just above the perichondrium, mobilizing the flap skin so that it can be advanced into the
Fig. 13. (A, B) Large defect involving the helix and posterior ear. (C) Transposition flap from the postauricular sulcus sutured into place. (D) Final result 3 months later.
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defect. This alternative form of the advancement flap, which is also known as a Burow’s flap, has the advantage of a broader vascular base than the more peninsular double-tangent advancement flap [4]. Once appropriate Burow’s triangles are removed, the flap can be easily sutured into place without distortion or cupping of the ear in most defects that are 1 to 2 cm. An alternative to the advancement flap is the transposition flap. Depending on the location of the defect, a transposition flap may be harvested from the posterior surface of the ear, the postauricular sulcus, or the preauricular skin. Defects located anteriorly on the superior helix can easily be closed by transposing flaps either from the postauricular sulcus or the preauricular ear (Fig. 13). When the defect is located more posteriorly on the superior helix and if the skin of the ear is loose and elastic, a simple transposition flap from the posterior surface of the ear can be
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accomplished for defects of up to 1.5 cm, without distortion of the shape of the auricle. Flaps are preferred over full-thickness grafts when the degree of vascularity of the wound base is in question. Also, if a defect has resulted in loss of skin on both the anterior and posterior surfaces of the ear, a flap is much more likely to survive and preserve the remaining cartilage. In the case of a substantial defect that involves both sides of the cartilage or a defect that requires cartilage graft reconstruction, a two-stage retroauricular pedicle flap is often the reconstruction of choice (see later). Split-thickness skin grafts are less useful on the superior helix because they are usually too thin to match well with the surrounding skin. When flaps are not an option and the vascularity of the wound base is in question, a split-thickness skin graft is a reasonable consideration for coverage and to avoid desiccation of cartilage.
Fig. 14. (A) Defect of the helix (lateral view). (B) Same defect (posterior view) with simple Burow’s triangle drawn perpendicular to the helix. (C) Lateral view following advancement flap. (D) Posterior view of closure of a Burow’s triangle.
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Midhelix In many ways, the midhelix is the most challenging of the subregions of the ear and yet is perhaps the most aesthetically noticeable on frontal and lateral views. Reconstructing this area is difficult because it is relatively isolated from any large donor pool. The nearest donor pools are the earlobe and the retroauricular scalp. The superior helix is often not a significant source of donor skin and laxity, and the posterior surface of the ear is also frequently tight and unyielding. As with small or superficial wounds, healing by second intention is a reasonable approach to consider. Full-thickness skin grafts are also useful in that skin can be imported from distant sites that match the helical skin in texture and thickness as long as there is ample vascularity within the wound base. Flaps are often preferred when they can be executed without distortion of the auricular cartilage because of the excellent vascular supply of the ear and the use of like skin for a repair. As with all helical defects, the advancement flap is frequently the
closure of choice. Typically, a single advancement flap for a midhelical defect would attempt to tap into the laxity of the earlobe inferiorly. Again, as with the superior helix, a single-tangent or a double-tangent advancement flap can be used. Because of the longer reach to the midhelix from the earlobe, the traditional double-tangent advancement flap will be longer and bears more risk of vascular compromise of the distal portion of the flap. Therefore, it is often preferable to limit the tangential incision to the anterior-most aspect of the defect along the helical rim and excise a Burow’s triangle perpendicular to the helix on the posterior surface of the ear (Fig. 14). The advancement flap is then raised by undermining the flap skin of the inferior helix and a portion of the earlobe and the lower aspect of the posterior ear. Generally, a great deal of tissue mobility can be achieved without distortion of the auricular cartilage and with acceptable diminution of the size of the earlobe. The vascular base of this flap is excellent and vascular compromise is unlikely. On occasion, a double-advancement flap from superior and inferior to the
Fig. 15. (A) Large defect of the superior helix and midhelix, with relatively small remnants of the superior helix and inferior helix remaining. (B) Reconstruction with wedge resection of the auricle in an attempt to re-create a semblence of the helix. Note a split-thickness skin graft was necessary because of the large skin-only portion of the defect on the posterior ear. (C) Three-month postoperative result with reasonable simulation of the original nautilus shape of the ear.
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defect may be necessary, tapping into the laxity of the helix superior to the defect and inferior to the defect. Care must be taken in helical advancement flaps to avoid cupping of the ear. This precaution limits the use of these flaps to defects that are between 1 and 2 cm of the ear, depending on the skin laxity and the size of the ear. Wedge closure of the ear is often an excellent choice, especially for defects of the midhelix. This technique does reduce the size of the ear, however, and when feasible, other options may be superior. In a defect involving a relatively small amount of the total curvature of the helix and in which some cartilage loss has occurred, a wedge closure is convenient and effective (Fig. 15). The most significant pitfall of a wedge closure is creation of ‘‘cupping’’ of the ear. If a simple V-shaped wedge is used in a relatively large defect, cupping can occur and will be noticeable on the anterior profile. When the defect is large enough that cupping is likely, a variation of the V-shaped wedge closure is to excise relatively elongated triangles parallel to the helix superiorly and inferiorly in addition to the triangular excision of cartilage extending perpendicular to the helix onto the antihelix and the conchal bowl (Fig. 16). This so-called ‘‘stellate’’ or ‘‘star-shaped’’ wedge closure is effective at decreasing the amount of cupping of the ear. This technique does cause an overall reduction in the area of the auricle, but as discussed earlier, this is often inconspicuous on anterior and lateral profile. In these
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cases, it is imperative to securely reapproximate the edges of the cartilage to reconstitute the nautilus shape of the auricle. A two-staged retroauricular flap is another excellent option, especially in large wounds that extend onto the anterior surface of the ear or which require cartilage grafts. The key to this flap is making a template of the defect. In designing this flap, it is helpful to imagine raising the skin off of the posterior ear and retroauricular area and tucking the denuded auricle underneath this flap of skin. The base of the flap is typically just peripheral to what would be the shadow of the helix. Wounds with no need for replacement of cartilage can be repaired with the skin of the flap simply sutured into the wound edges of the helix and anterior surface of the ear to be severed 3 weeks later (Fig. 17). The flap donor defect can be either allowed to heal by second intention or covered with a split-thickness skin graft. In more complex auricular defects involving loss of cartilage, the first step of the retroauricular flap is to make templates of the missing cartilage (Fig. 18). The most common donor site for cartilage grafts is the contralateral conchal bowl. Here, appropriate curvature and contour of cartilage grafts can be selected without compromising the donor auricle. The cartilage graft is then transferred to the defect and sutured into place with either absorbable or nonabsorbable interrupted suture. Once the cartilage grafts are secure, the pedicled retroauricular flap
Fig. 16. (A) Large defect involving most of the midhelix. (B) Wedge-type closure using the stellate wedge configuration, which removes smaller triangles of cartilage superiorly and inferiorly along the helical groove. The size of the ear is slightly smaller but the shape is maintained.
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Fig. 17. (A) Large defect of the midhelix and antihelical skin. (B) Repair with a two-stage retroauricular pedicle flap. (C) Three weeks later, the pedicle is severed and the skin is resutured. (D) Six-month postoperative results.
can be fashioned and executed in the same manner. The flap ‘‘sandwiches’’ the cartilage graft between the posterior surface of the ear, which provides vascular support from both the surfaces. This technique usually requires the use of the postauricular skin and the retroauricular skin as donor tissue for the flap. The pedicle can be severed in 3 weeks. A second revision may be necessary to refine the results and reestablish the helical groove. In some cases, the helical groove can be accentuated by basting sutures placed parallel to the helix in the groove.
Inferior helix and earlobe Defects of the inferior helix and earlobe are usually considerably easier to reconstruct than those of the midhelix. Often, healing by second intention is an excellent alternative in smaller defects. Defects limited to the inferior helix may be repaired with a full-thickness skin graft, which usually provides excellent cosmesis and functionality when relatively
superficial. Full-thickness grafts are not often as useful in defects of the soft, flexible earlobe because wound contraction often occurs, resulting in pincushioning of the graft and distortion of the lobe. If a fullthickness skin graft is the most desirable alternative for an earlobe defect, then placement of a thin wafer of cartilage can prevent deformation from contraction because of its rigidity. Often, defects in this area can be closed primarily either using a wedge-type resection or a simple side-to-side closure. When necessary, it is reasonable to reduce the size of the earlobe because asymmetry is often inconspicuous on anterior and lateral profile. The advancement flap is useful in reconstruction of intermediate-sized defects involving the inferior helix and the earlobe (Fig. 19). Again, this reconstruction can be accomplished with either the doubletangent advancement flap or a single-tangent advancement flap. Very large defects of the earlobe can be intimidating at first sight (Fig. 20). This region is one of the more forgiving areas on the face, however, and often
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Fig. 18. (A) Large recurrent basal cell carcinoma involving the antihelix, helical grove, and conchal bowl. (B) Defect after Mohs surgery includes loss of a large portion of cartilage of the midhelix and antihelix. (C) Cartilage graft from contralateral conchal bowl. (D) Cartilage graft sutured into place. (E) Retroauricular pedicle flap sutured into place resurfacing the helix and antihelical defect. A full-thickness skin graft is used to resurface the defect of the conchal bowl.
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Fig. 19. (A) Defect of the lower helix. (B) Advancement flap using the laxity of the earlobe. (C) One-year postoperative follow-up.
Fig. 20. (A) An earlobe and preauricular defect resulting in the detachment of the earlobe from the body of the ear. (B) Earlobe sutured in a wedgelike fashion reconstituting the normal shape of the ear. The preauricular portion of the defect is closed independently.
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Fig. 21. (A) Large defect of the earlobe extending into the postauricular and preauricular skin. (B) Resuturing of the lobe with an attempt to reconstitute its original contour. (C) Six months postoperatively, with good aesthetic results.
a remnant of the earlobe can be reconfigured in a lobular fashion very closely approximating an earlobe. As long as the final configuration of the earlobe has a semicircular curvature, it is often inconspicuous to the casual observer (Fig. 21).
tive option. Therefore, familiarity of the most useful reconstructive options in a given anatomic location will enhance the surgeon’s ability to simply and effectively reconstruct the ear in an aesthetic and a functional fashion.
Summary
References
Reconstruction strategies for the ear should address the major aesthetic goals of maintaining the helical curvature and the symmetric frontal profile. When the auditory canal is involved, maintaining its patency is a major functional goal. The strategy in auricular reconstruction is greatly simplified when the defect is considered according to its anatomic location. The anatomic location, because of its topographic features and adjacent donor pools, will dictate the most appropriate reconstruc-
[1] Allison GR. Anatomy of the external ear. Clin Plast Surg 1978;5:419 – 22. [2] Park C, Lineaweaver WC, Rumly TO. Arterial supply of the anterior ear. Plast Reconstr Surg 1992;90:38 – 44. [3] Ceilley RI. The ear. In: Roenigk RK, Roenigk Jr HH, editors. Dermatologic surgery: principles and practice. 2nd edition. New York7 Marcel Dekker; 1996. p. 273 – 91. [4] Brodland DG, Pharis D. Flaps. In: Bolognia JL, Jorizzo JL, Rapini RP, editors. Dermatology. London7 Mosby; 2003. p. 2287 – 303.
Auricular reconstruction David G. Brodland, MD Departments of Dermatology and Otolaryngology, University of Pittsburgh, South Hills Medical Building, 575 Coal Valley Road, Suite 360, Pittsburgh, PA 15025, USA
The auricle is a complex-looking structure, with undulating topography and structural characteristics ranging from firm, rigid cartilage to the soft, spongy, and elastic earlobe. With the two primary goals of reconstruction being restoration of form and function, these complex anatomic features make the former a challenge. Yet the function of the auricle in humans is relatively simple and basic. The main functional consideration during reconstruction of the auricle is maintaining the patency of the external auditory canal (EAC). There are key anatomic features of the ear that make reconstruction of the auricle unique and that can be taken advantage of by the surgeon to optimize its reconstruction. These features include the following: a rich blood supply; a complex topography, which is highly variable from person to person; a relatively inconspicuous lateral location with limited visibility on frontal view; and a very firm infrastructure of most of the auricle [1 – 3]. These aspects affect reconstruction of the ear and profoundly affect the skill set required for success. The goals of auricular reconstruction can be categorized into primary and secondary goals (Box 1). There are three primary goals: (1) maintaining function through patency of the auditory canal, (2) maintaining the overall anterior profile, and (3) maintaining the lateral profile. The anterior profile includes the modest projection from the side of the head, which should be slightly greater superiorly than inferiorly. The helical rim and the helical groove are typically the most visible aspects on frontal view. The lateral profile is characterized by the nautilus-like shape, with smooth curvature at the perimeter and the
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lobule of the ear, which is approximately one third of the vertical height of the remainder of the ear. If the final result of the reconstruction achieves these three primary goals, most surgeons would find the results very satisfactory. Secondary goals of auricular reconstruction include the preservation or recreation of the ear’s complex topography, camouflage of the scar, and maintenance of the size of the ear. Although these goals are not inconsequential, for various reasons they are all somewhat less critical than the primary goals of reconstruction. The maintenance of the anterior and lateral profile have more to do with the method of reconstruction whereas maintaining patency of the EAC is more an issue of wound management and, in particular, the prevention of scar contraction. The assessment of the nature of the wound involving the EAC is the critical factor in deciding how to manage wounds in this area. Typically, if the cartilage of the EAC is intact and the wound does not involve the entire circumference of the EAC wall, then second-intention healing is rarely complicated by constriction of the EAC. In the case of a circumferential wound within the EAC or significant loss of portions or all of its cartilaginous wall, an effort to decrease or eliminate scar contraction is advisable. The camouflage of the scars of reconstruction is secondary mainly because most scars, unless hypertrophic or keloidal, blend in inconspicuously. The complex topography also helps in making scars inconspicuous. Maintaining the size of the ears is a secondary issue in reconstruction for several reasons. Because of the lateral location of the ears, size differences between the two ears are typically inconspicuous. Size changes are most evident on lateral view and
0733-8635/05/$ – see front matter D 2005 Elsevier Inc. All rights reserved. doi:10.1016/j.det.2004.08.008
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Box 1. Primary and secondary goals in auricular reconstruction Primary 1. Function (patent auditory canal) 2. Maintain anterior profile 3. Maintain lateral profile Secondary 1. Preservation and restoration of topography 2. Camouflage scar 3. Maintain size of ear
would require a concerted effort to compare the size of one ear with the other. As long as the lateral, nautilus-like profile of the helix is maintained, minor size changes do not draw attention to the ear. Reconstruction of the ear is simplified by recognizing its distinct anatomic zones. Depending on the location of the defect and the zone or zones involved, reconstruction options vary greatly. The three basic zones of the ear include the anterior ear, the posterior ear, and the helical ear. The anterior ear includes the conchal bowl, the antihelix, and the crus of the antihelix. The helical zone of the ear can be broken up into the superior helix, the midhelix, and the inferior helix/ lobule. Each of these zones is structurally unique and is reconstructed in an equally unique fashion.
Posterior ear The choice of reconstruction for the posterior ear is closely related to functional concerns. Most wounds that occupy less than half of the total surface of the posterior ear and sometimes even greater than half of the posterior ear can heal by second intention without significant distortion of the anterior or lateral profile of the ear (Fig. 1). When the cartilaginous structure of the ear has been compromised, however, greater caution is necessary with regard to secondintention healing and maintaining the profiles of the ear. Another functional issue arises when the defect involves either a substantial portion of the posterior ear or extends into the postauricular sulcus and onto the skin overlying the mastoid bone. If these wounds are allowed to heal by second intention, sometimes the ear is effectively ‘‘pinned back,’’ which can be uncomfortable and make eyeglasses fit improperly. In the event that healing by second intention is not feasible, the most commonly used reconstructive option is grafting. Both full-thickness skin grafts and split-thickness skin grafts are useful, but there are several features of split-thickness grafts that make them a serious consideration for the postauricular ear. A split-thickness skin graft has a low nutritional requirement, making successful engraftment very likely. Because the posterior ear is not highly visible, the aesthetic disadvantages of split-thickness skin grafts are not as great an issue. Even so, the skin on the posterior ear is naturally very thin and is usually well simulated in appearance by split-thickness skin grafts. There are many potential donor areas for split-thickness skin grafts, but the skin overlying
Fig. 1. (A) Superficial defect of posterior ear. (B) Results at 1-year follow-up.
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Fig. 2. (A) Defect of the posterior ear extending into the postauricular sulcus. (B) Side-to-side closure using buried horizontal mattress sutures.
the mastoid process is a convenient and effective donor site for split-thickness skin grafts up to 4 cm. This donor site tends to heal very quickly not only because wounds on the head do so by nature but also because of the high density of adnexal structure contributing to the rapid re-epithelialization of the donor site. Smaller defects located close to or within the postauricular sulcus can be conveniently closed with-
out functional or aesthetic consequences with dermal horizontal mattress sutures drawing the wound edges closed in a direction parallel to the sulcus (Fig. 2). Small Burow’s triangles can be excised superiorly and inferiorly. Epidermal sutures are not usually necessary, and often it is preferable not to undermine extensively or at all to avoid tenting across the sulcus. This technique is usually limited to wounds smaller than 2 cm in horizontal diameter.
Fig. 3. (A) Large defect of the posterior ear and retroauricular skin. (B) Near-total loss of cartilage results in near-complete loss of the ear’s rigid structure. (C) Posterior view of defect showing near-total loss of cartilage. (D) The remnant of the ear is inset and tacked to the retroauricular defect, providing it with rigid backing and reconstituting its lateral profile.
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An uncommon situation is the loss of most of the cartilage having the anterior surface of the ear intact but without any rigid structure. In such cases, it may be impractical to obtain cartilage grafts large enough to reconstitute the auricular infrastructure. A reasonable alternative is to inset the ear onto the rigid retroauricular surface using this rigid structure in lieu of cartilage (Fig. 3). There is an effect on the anterior profile of the ear because the remnant of the ear is pinned back. It therefore will project less from the side of the ear. It does maintain both function and lateral profile, however, which may be a reasonable compromise in a difficult situation. There are other flaps that can be used to reconstruct the posterior ear and, in some situations, may be absolutely necessary for the posterior ear. In the current author’s experience, however, simpler is usually better and very effective. Therefore, healing by second intention, grafting, or primary closure are the most commonly used reconstruction methods for defects in this anatomic zone.
Anterior ear Reconstruction of the anterior ear is guided by the same principles as other areas of the ear—that is, to maintain form and function of the ear. The first and foremost consideration of most smaller wounds not involving a significant amount of cartilage is secondintention healing (Fig. 4). The texture and color of the skin combined with the rigid infrastructure make deformation an unlikely event. With the exception of large wounds within the EAC, the alteration of function is also a rare complication if wounds are allowed to heal by second intention. Factors that may favor reconstruction of an anterior ear defect include large defects, which, if allowed to heal by second intention, would deform
the auricle or affect the patency of the EAC. Other factors include large wounds with large amounts of exposed cartilage, which may result in a chondritis secondary to exposure and desiccation. Another relative indication for wound closure is a defect that would be difficult for the patient to take care of if allowed to heal by second intention, either because the patient is unable to effectively cleanse and rebandage the wound or the patient has no one available to assist him or her in wound care. Some patients who wear hearing aids benefit from the more rapid healing afforded by reconstruction, which allows them to wear their hearing aid more quickly and comfortably following surgery. Because of the naturally thin skin typically found on the anterior ear, the split-thickness skin graft is often the easiest and most effective way of reconstructing this portion of the ear (Fig. 5). The nutritional requirements of a split-thickness graft are less than a full-thickness graft, making it ideal in wounds extending to the perichondrium. A fullthickness skin graft is often the preferred closure in a well-vascularized wound base and in patients with thick, sebaceous skin. Regardless of the type of graft used to reconstruct the anterior ear, by definition, a second wound is being created in the harvesting of the graft. Therefore, it is wise to select the donor site judiciously so that healing is made as convenient as possible for the patient. Furthermore, the selection of graft type and donor site should be made with consideration of what the optimal thickness and skin characteristics would be for that patient. Some patients’ anterior ear skin is quite thick and others’ anterior ear skin is extremely thin. The recognition of these characteristics can direct the surgeon’s choice of donor site. Often, a donor site in the periauricular region is most convenient and optimal in terms of thickness and skin consistency. An excellent site for a split-thick-
Fig. 4. (A) Defect of the anterior ear. (B) Results 3 months after second-intention healing.
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Fig. 5. (A) Large defect of the anterior ear. (B) Reconstruction with split-thickness skin graft harvested from the retroauricular skin over the mastoid process.
ness graft of small- to moderate-sized defects is the skin overlying the mastoid bone. The hair in this area can be shaved, and the split-thickness graft can be harvested by either freehand dermaplaning with a scalpel or with one of the split-thickness graftharvesting tools, such as the Goulian skin knife and guards (Weck, Durham, North Carolina). As described earlier, the re-epithelialization time of the donor site is remarkably fast. Further, any resulting scar is camouflaged by the regrowth of hair, which is unaltered by the superficial harvesting of the graft. Alternatively, the more traditional split-thickness donor sites can be used, including the anterior and lateral thigh. Full-thickness skin grafts are most conveniently harvested from the retroauricular skin. Depending on the size of the ear, 2- to 3-cm grafts can be obtained from this area. A template is made of the defect and used for incising the graft by placing approximately one half of the template on the posterior surface of the ear and the other half on the retroauricular skin. The donor site can often be closed by horizontal dermal sutures placed across the wound, such that the wound edge on the posterior ear is sutured to the wound edge of the retroauricular skin. Care must be taken to avoid pinning back the ear. Full-thickness skin grafts from other donor sites can be used. Many of the other traditional donor sites yield grafts that are too thick to match the normal skin characteristics of the anterior ear, however. For example, grafts from the supraclavicular fossa are often too thick to satisfactorily match the anterior ear. Extensive defects of the EAC may require reconstruction to preserve the patency of the canal. Wounds involving most or all of the circumference of the canal or wounds with extensive cartilage loss
require reconstructive intervention because contraction can threaten canal patency. Perhaps the easiest and most effective way of reducing contraction within the ear canal is with a skin graft. Thin full-thickness skin grafts may be effective and are reported to decrease scar contractions better than split-thickness skin grafts. Because of the small caliber of the EAC, however, a splitthickness skin graft is highly effective and less likely to cause a narrowing of the canal from edema of the graft. Sometimes full-thickness skin grafts swell or thicken in the months following engraftment, reducing the overall caliber of the canal. Split-thickness skin grafts are not only thinner and less likely to thicken and swell, but they also have a lower nutritional requirement, making successful engraftment more likely (Fig. 6). Some flaps have been reported for the reconstitution of the EAC; however, they are at greater risk for postoperative edema and inadvertent occlusion of the otherwise patent canal. A helpful technique for the nonhelical posterior surface of the ear and anterior surface of the ear when the defect has a significant amount of exposed cartilage stripped of its perichondrium is full-thickness perforation of the cartilage. This technique is most conveniently performed with 3-mm or 4-mm punch holes created by a skin punch tool. The relatively avascular cartilage, when stripped of its perichondrium, will not support skin grafts. The perforation through to the opposite side of the ear creates portals through which the vascular supply from the subcutaneous tissue on the opposite side of the ear can be made a source of oxygen and nutrients to support the graft (Fig. 7). Likewise, in defects that are 1.5 to 2 cm without perichondrium that are being allowed to heal by second intention, perforation can
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Fig. 6. (A) Large defect involving conchal bowl with the wound extending deep into the EAC. (B) Reconstruction of the preauricular portion of the defect with a flap and the conchal bowl and EAC with a split-thickness skin graft. (C) Three-month postoperative result with excellent maintenance of EAC patency.
greatly speed the rate of healing because of granulation tissue growing through the perforations from the opposite side of the ear. Typically, more perforations are necessary for grafting than for secondintention healing, with no more than approximately
5 mm of cartilage intervening between the perforations. To potentiate healing by second intention, one perforation per square centimeter is usually sufficient. Another useful technique in the reconstruction of larger ear defects where enough cartilage has been
Fig. 7. (A) Conchal bowl defect with exposed cartilage stripped of perichondrium. Perforation being made with a punch biopsy tool. (B) Perforation enables granulation tissue from the posterior ear, providing vascular tissue to support rapid re-epithelialization of the wound.
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Fig. 8. (A) Large anterior ear defect. (B) Loss of helical and antihelical cartilage results in severe structural compromise. (C) Cartilage grafts from contralateral ear are used in spoke-and-wheel configuration to reconstitute and maintain the structure of the ear. (D) A split-thickness skin graft is harvested from over the mastoid bone. (E) The split-thickness skin graft is sutured over the cartilage grafts to resurface the wound. (F) Follow-up at 6 months shows excellent preservation of the shape and appearance of the ear.
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excised to impair the structural integrity of the auricle is the use of cartilaginous struts. The ideal wound for this technique is typically one where enough of the auricular cartilage is preserved to maintain the shape of the ear but where there is not enough structural integrity to prevent deformation of the shape with normal contraction of the wound (Fig. 8). These cartilaginous struts can be harvested from the margins of the cartilaginous wound or the contralateral ear. Typically, the strut is 3 to 4 mm in width and measured to be slightly longer than the width of the cartilaginous defect. These struts are then placed across the defect and anchored with sutures into the base of the wound and to both sides of the cartilaginous defect. Grafts or flaps can then be laid over the cartilage. As long as close contact to a vascularized base of the wound is maintained, the cartilaginous strut can be expected to engraft. Split-thickness skin grafts often maintain viability through vascular bridging over the avascular cartilaginous graft. The same principle of using thin strips of cartilage across cartilaginous defects is used with cartilage flaps for auricular reconstruction. Again, the ideal situation for this technique is a defect in which the helix has been preserved and yet lacks sufficient structure to maintain normal shape during scar contraction (Fig. 9). In this situation, a cartilaginous flap can be created by incising a narrow 2- to 3-mm – thick strip of cartilage tangential to the defect, leaving it attached at one end. The cartilage flap can then be carefully bent at a 90° angle and fixated by suturing the flap into the wound base and suturing its distal end into the cartilaginous helical remnant. Graft or flap closure of the cutaneous defect completes the reconstruction. Presumably, the cartilaginous flap remains vascularized, which may ensure its survival. A few defects of the anterior ear require reconstruction with flaps. Flaps are typically reserved for situations in which a vascularized resurfacing of the auricle is needed. These situations include defects in which there is extensive exposure of cartilage that has been stripped of its perichondrium. In addition, defects that require cartilage grafting to reconstitute the structural integrity of the auricle are best resurfaced with a well-vascularized flap. These local flaps are usually based on the retroauricular skin posteriorly or the preauricular skin. The two-stage retroauricular pedicle flap is most often used in defects that involve reconstruction of the helix. It can also be used in defects limited to the anterior surface of the ear but will be described in more detail later. A flap that is frequently described for large defects of the anterior ear is the ‘‘flip-flop flap,’’ also known as the retroauricular pull-through flap. In this flap, a
template is made of the defect on the anterior surface of the ear and used to incise a flap on the retroauricular skin and in the postauricular groove (Fig. 10). This is an island flap with a pedicle based predominantly in the retroauricular groove. The flap is carefully reflected from posterior to anterior, leaving a substantial subcutaneous pedicle anteriorly. If a full-thickness communication to the anterior surface of the ear through the conchal bowl does not already exist, it should be made to deliver the island flap to the anterior ear defect. If cartilage grafting is necessary, it is then sutured into position and the flap is sutured into place over top. If the donor site cannot be closed primarily, it can be partially closed and allowed to heal by second intention or grafted. These flaps are robust because of the excellent vascular supply in and around the ear. This flap is most useful in inhibiting wound contracture that would be deforming to the shape of the ear and in instances when cartilage grafts from the contralateral ear are required to maintain its structural integrity. There may be times when a two-stage pedicle flap using the preauricular skin is useful. In this case, a superiorly based pedicle can be created and non – hair-bearing auricular skin can be imported into the anterior surface of the ear to provide a vascularized resurfacing of a defect. This pedicle is transected 2 to 3 weeks later, and the donor site closed primarily.
Reconstruction of the helix The helix is the structure of the auricle that is most responsible for its normal shape and position. Not only is it the most common location of skin cancers of the ear but it is also the most delicate and easily deformed structure, making it the most challenging aspect of ear reconstruction. The helix is conveniently broken up into three zones: the superior, mid-, and inferior helix. The superior portion is that which is largely horizontally oriented, whereas the inferior helix includes the inferior 1 cm of the helix and the earlobe. The remaining helix is the midhelix. The superior helix is characterized by potential donor skin at the anterior attachment of the ear, the posterior ear, and retroauricular sulcus. The midhelix has a more limited donor pool, which is located on a relatively rigid portion of the ear. This donor pool consists of the helix superiorly and inferiorly and the posterior ear. It is this region that, because of its isolation from substantial donor pools, makes it the most common site for the two-stage retroauricular pedicle flaps. The inferior helix, in contrast, is adjacent to the earlobe, which is very elastic tissue
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Fig. 9. (A) Large posterior ear defect with massive loss of cartilage but preservation of the helical and the conchal bowl cartilage. (B) A cartilage flap is fashioned from the remnant cartilage of the conchal bowl and carefully transposed parallel to the postauricular sulcus and perpendicular to the helix. The flap is affixed by suturing and serves as a supportive spoke between the conchal bowl and helical rim. (C) A full-thickness skin graft is applied to the defect. (D) Immediately following surgery, the previous collapse of the helix is prevented and the lateral profile is maintained. (E) Postoperative result at 3 months, posterior view. (F) Postoperative result at 3 months, lateral view, with excellent preservation of the helix.
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Fig. 11. (A) Postoperative defect of the superior helix. (B) Full-thickness skin graft from the postauricular sulcus sutured into place. (C) Three-month postoperative result.
and as such an ample source of donor skin. Although this elasticity is useful in reconstructing defects superior to the earlobe, the earlobe’s lack of rigid infrastructure results in the biggest challenge of reconstruction of the earlobe, which is maintaining its shape.
Superior helix The most common closures of the superior helix include helical advancement, transposition flaps, and full-thickness skin grafts. Two-stage pedicle flaps may also be useful in large defects of this location. Well-vascularized wounds are often most easily repaired with full-thickness skin grafts harvested
from either the postauricular sulcus or the preauricular skin (Fig. 11). Grafts have the advantage of not creating any distortional countertensions, which can be a problem with flaps. The biggest unknown factor is the degree to which a full-thickness graft will survive. Grafts on the ear are more prone to disruption of vascular inosculation because it is difficult to adequately protect and pad the ear from accidental injury. The graft can be protected and stabilized using tie-over bolster dressing, which can reduce the chance of disruption of the graft and improve the chance of complete survival. Helical advancement flaps are the workhorse flap for the superior and inferior helix. For the superior helix, a sizable donor pool is available at the anterior attachment of the ear (Fig. 12). Typically, a skin flap
Fig. 10. (A) Large defect of the anterior ear with loss of most of the conchal bowl and portions of the antihelical cartilage. (B) Severe compromise of structure of the ear caused by cartilage loss. (C) View of the retroauricular flap and posterior surface of the ear. An incision has been made through the posterior surface of the ear through which the retroauricular flap will be delivered to the anterior surface of the ear. (D) Delivery of the retroauricular skin flap through the posterior ear to the anterior surface of the ear. (E) Flap sutured into place. (F) Six-month postoperative result with satisfactory maintenance of the auricular profile.
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Fig. 12. (A) Defect of the superior helix. (B) Anteriorly based advancement flap reconstruction.
is created by a tangential incision located along the rim of the helix. A second tangential excision is commonly made parallel to the first on the posterior surface of the ear, creating a peninsular skin flap that is based anteriorly at the attachment of the ear to the cheek. This form of advancement flap is known as a double-tangent advancement flap.
An alternative approach is to forgo the second parallel tangential incision and instead remove a Burow’s triangle from the posterior surface of the ear perpendicular to the first tangential incision. The flap is then raised by undermining in the deep subcutaneous tissue just above the perichondrium, mobilizing the flap skin so that it can be advanced into the
Fig. 13. (A, B) Large defect involving the helix and posterior ear. (C) Transposition flap from the postauricular sulcus sutured into place. (D) Final result 3 months later.
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defect. This alternative form of the advancement flap, which is also known as a Burow’s flap, has the advantage of a broader vascular base than the more peninsular double-tangent advancement flap [4]. Once appropriate Burow’s triangles are removed, the flap can be easily sutured into place without distortion or cupping of the ear in most defects that are 1 to 2 cm. An alternative to the advancement flap is the transposition flap. Depending on the location of the defect, a transposition flap may be harvested from the posterior surface of the ear, the postauricular sulcus, or the preauricular skin. Defects located anteriorly on the superior helix can easily be closed by transposing flaps either from the postauricular sulcus or the preauricular ear (Fig. 13). When the defect is located more posteriorly on the superior helix and if the skin of the ear is loose and elastic, a simple transposition flap from the posterior surface of the ear can be
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accomplished for defects of up to 1.5 cm, without distortion of the shape of the auricle. Flaps are preferred over full-thickness grafts when the degree of vascularity of the wound base is in question. Also, if a defect has resulted in loss of skin on both the anterior and posterior surfaces of the ear, a flap is much more likely to survive and preserve the remaining cartilage. In the case of a substantial defect that involves both sides of the cartilage or a defect that requires cartilage graft reconstruction, a two-stage retroauricular pedicle flap is often the reconstruction of choice (see later). Split-thickness skin grafts are less useful on the superior helix because they are usually too thin to match well with the surrounding skin. When flaps are not an option and the vascularity of the wound base is in question, a split-thickness skin graft is a reasonable consideration for coverage and to avoid desiccation of cartilage.
Fig. 14. (A) Defect of the helix (lateral view). (B) Same defect (posterior view) with simple Burow’s triangle drawn perpendicular to the helix. (C) Lateral view following advancement flap. (D) Posterior view of closure of a Burow’s triangle.
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Midhelix In many ways, the midhelix is the most challenging of the subregions of the ear and yet is perhaps the most aesthetically noticeable on frontal and lateral views. Reconstructing this area is difficult because it is relatively isolated from any large donor pool. The nearest donor pools are the earlobe and the retroauricular scalp. The superior helix is often not a significant source of donor skin and laxity, and the posterior surface of the ear is also frequently tight and unyielding. As with small or superficial wounds, healing by second intention is a reasonable approach to consider. Full-thickness skin grafts are also useful in that skin can be imported from distant sites that match the helical skin in texture and thickness as long as there is ample vascularity within the wound base. Flaps are often preferred when they can be executed without distortion of the auricular cartilage because of the excellent vascular supply of the ear and the use of like skin for a repair. As with all helical defects, the advancement flap is frequently the
closure of choice. Typically, a single advancement flap for a midhelical defect would attempt to tap into the laxity of the earlobe inferiorly. Again, as with the superior helix, a single-tangent or a double-tangent advancement flap can be used. Because of the longer reach to the midhelix from the earlobe, the traditional double-tangent advancement flap will be longer and bears more risk of vascular compromise of the distal portion of the flap. Therefore, it is often preferable to limit the tangential incision to the anterior-most aspect of the defect along the helical rim and excise a Burow’s triangle perpendicular to the helix on the posterior surface of the ear (Fig. 14). The advancement flap is then raised by undermining the flap skin of the inferior helix and a portion of the earlobe and the lower aspect of the posterior ear. Generally, a great deal of tissue mobility can be achieved without distortion of the auricular cartilage and with acceptable diminution of the size of the earlobe. The vascular base of this flap is excellent and vascular compromise is unlikely. On occasion, a double-advancement flap from superior and inferior to the
Fig. 15. (A) Large defect of the superior helix and midhelix, with relatively small remnants of the superior helix and inferior helix remaining. (B) Reconstruction with wedge resection of the auricle in an attempt to re-create a semblence of the helix. Note a split-thickness skin graft was necessary because of the large skin-only portion of the defect on the posterior ear. (C) Three-month postoperative result with reasonable simulation of the original nautilus shape of the ear.
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defect may be necessary, tapping into the laxity of the helix superior to the defect and inferior to the defect. Care must be taken in helical advancement flaps to avoid cupping of the ear. This precaution limits the use of these flaps to defects that are between 1 and 2 cm of the ear, depending on the skin laxity and the size of the ear. Wedge closure of the ear is often an excellent choice, especially for defects of the midhelix. This technique does reduce the size of the ear, however, and when feasible, other options may be superior. In a defect involving a relatively small amount of the total curvature of the helix and in which some cartilage loss has occurred, a wedge closure is convenient and effective (Fig. 15). The most significant pitfall of a wedge closure is creation of ‘‘cupping’’ of the ear. If a simple V-shaped wedge is used in a relatively large defect, cupping can occur and will be noticeable on the anterior profile. When the defect is large enough that cupping is likely, a variation of the V-shaped wedge closure is to excise relatively elongated triangles parallel to the helix superiorly and inferiorly in addition to the triangular excision of cartilage extending perpendicular to the helix onto the antihelix and the conchal bowl (Fig. 16). This so-called ‘‘stellate’’ or ‘‘star-shaped’’ wedge closure is effective at decreasing the amount of cupping of the ear. This technique does cause an overall reduction in the area of the auricle, but as discussed earlier, this is often inconspicuous on anterior and lateral profile. In these
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cases, it is imperative to securely reapproximate the edges of the cartilage to reconstitute the nautilus shape of the auricle. A two-staged retroauricular flap is another excellent option, especially in large wounds that extend onto the anterior surface of the ear or which require cartilage grafts. The key to this flap is making a template of the defect. In designing this flap, it is helpful to imagine raising the skin off of the posterior ear and retroauricular area and tucking the denuded auricle underneath this flap of skin. The base of the flap is typically just peripheral to what would be the shadow of the helix. Wounds with no need for replacement of cartilage can be repaired with the skin of the flap simply sutured into the wound edges of the helix and anterior surface of the ear to be severed 3 weeks later (Fig. 17). The flap donor defect can be either allowed to heal by second intention or covered with a split-thickness skin graft. In more complex auricular defects involving loss of cartilage, the first step of the retroauricular flap is to make templates of the missing cartilage (Fig. 18). The most common donor site for cartilage grafts is the contralateral conchal bowl. Here, appropriate curvature and contour of cartilage grafts can be selected without compromising the donor auricle. The cartilage graft is then transferred to the defect and sutured into place with either absorbable or nonabsorbable interrupted suture. Once the cartilage grafts are secure, the pedicled retroauricular flap
Fig. 16. (A) Large defect involving most of the midhelix. (B) Wedge-type closure using the stellate wedge configuration, which removes smaller triangles of cartilage superiorly and inferiorly along the helical groove. The size of the ear is slightly smaller but the shape is maintained.
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Fig. 17. (A) Large defect of the midhelix and antihelical skin. (B) Repair with a two-stage retroauricular pedicle flap. (C) Three weeks later, the pedicle is severed and the skin is resutured. (D) Six-month postoperative results.
can be fashioned and executed in the same manner. The flap ‘‘sandwiches’’ the cartilage graft between the posterior surface of the ear, which provides vascular support from both the surfaces. This technique usually requires the use of the postauricular skin and the retroauricular skin as donor tissue for the flap. The pedicle can be severed in 3 weeks. A second revision may be necessary to refine the results and reestablish the helical groove. In some cases, the helical groove can be accentuated by basting sutures placed parallel to the helix in the groove.
Inferior helix and earlobe Defects of the inferior helix and earlobe are usually considerably easier to reconstruct than those of the midhelix. Often, healing by second intention is an excellent alternative in smaller defects. Defects limited to the inferior helix may be repaired with a full-thickness skin graft, which usually provides excellent cosmesis and functionality when relatively
superficial. Full-thickness grafts are not often as useful in defects of the soft, flexible earlobe because wound contraction often occurs, resulting in pincushioning of the graft and distortion of the lobe. If a fullthickness skin graft is the most desirable alternative for an earlobe defect, then placement of a thin wafer of cartilage can prevent deformation from contraction because of its rigidity. Often, defects in this area can be closed primarily either using a wedge-type resection or a simple side-to-side closure. When necessary, it is reasonable to reduce the size of the earlobe because asymmetry is often inconspicuous on anterior and lateral profile. The advancement flap is useful in reconstruction of intermediate-sized defects involving the inferior helix and the earlobe (Fig. 19). Again, this reconstruction can be accomplished with either the doubletangent advancement flap or a single-tangent advancement flap. Very large defects of the earlobe can be intimidating at first sight (Fig. 20). This region is one of the more forgiving areas on the face, however, and often
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Fig. 18. (A) Large recurrent basal cell carcinoma involving the antihelix, helical grove, and conchal bowl. (B) Defect after Mohs surgery includes loss of a large portion of cartilage of the midhelix and antihelix. (C) Cartilage graft from contralateral conchal bowl. (D) Cartilage graft sutured into place. (E) Retroauricular pedicle flap sutured into place resurfacing the helix and antihelical defect. A full-thickness skin graft is used to resurface the defect of the conchal bowl.
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Fig. 19. (A) Defect of the lower helix. (B) Advancement flap using the laxity of the earlobe. (C) One-year postoperative follow-up.
Fig. 20. (A) An earlobe and preauricular defect resulting in the detachment of the earlobe from the body of the ear. (B) Earlobe sutured in a wedgelike fashion reconstituting the normal shape of the ear. The preauricular portion of the defect is closed independently.
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Fig. 21. (A) Large defect of the earlobe extending into the postauricular and preauricular skin. (B) Resuturing of the lobe with an attempt to reconstitute its original contour. (C) Six months postoperatively, with good aesthetic results.
a remnant of the earlobe can be reconfigured in a lobular fashion very closely approximating an earlobe. As long as the final configuration of the earlobe has a semicircular curvature, it is often inconspicuous to the casual observer (Fig. 21).
tive option. Therefore, familiarity of the most useful reconstructive options in a given anatomic location will enhance the surgeon’s ability to simply and effectively reconstruct the ear in an aesthetic and a functional fashion.
Summary
References
Reconstruction strategies for the ear should address the major aesthetic goals of maintaining the helical curvature and the symmetric frontal profile. When the auditory canal is involved, maintaining its patency is a major functional goal. The strategy in auricular reconstruction is greatly simplified when the defect is considered according to its anatomic location. The anatomic location, because of its topographic features and adjacent donor pools, will dictate the most appropriate reconstruc-
[1] Allison GR. Anatomy of the external ear. Clin Plast Surg 1978;5:419 – 22. [2] Park C, Lineaweaver WC, Rumly TO. Arterial supply of the anterior ear. Plast Reconstr Surg 1992;90:38 – 44. [3] Ceilley RI. The ear. In: Roenigk RK, Roenigk Jr HH, editors. Dermatologic surgery: principles and practice. 2nd edition. New York7 Marcel Dekker; 1996. p. 273 – 91. [4] Brodland DG, Pharis D. Flaps. In: Bolognia JL, Jorizzo JL, Rapini RP, editors. Dermatology. London7 Mosby; 2003. p. 2287 – 303.