Auricular reconstruction after oncological resection

Auricular reconstruction after oncological resection

AURICULAR RECONSTRUCTION AFTER ONCOLOGICAL RESECTION BARRY L. EPPLEY, MD, DMD A variety of ear defects can occur after resection of malignant tumors,...

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AURICULAR RECONSTRUCTION AFTER ONCOLOGICAL RESECTION BARRY L. EPPLEY, MD, DMD

A variety of ear defects can occur after resection of malignant tumors, which presents the option for a diverse array of surgical techniques for their reconstruction. Because the functional demands of the ear are few and the opposite ear is usually unaffected, reconstruction should focus on the position, size, and contour of the resected ear. In skin-only defects, secondary healing, skin grafts, and direct closure are effective options. In smaller partial- and full-thickness defects, wedge closures and local chondrocutaneous flaps are effective one-stage techniques. In larger full-thickness defects, staged local and regional flaps with cartilage grafts can recreate the shape and contour of the ear. In total-ear defects, osseointegrated mastoid implants for prosthetic retention offer the most effective and rapid method for ear replacement.All of these reconstructivetechniquesare outlined and the indicationsfor their use discussed. Copyright 9 1999 by W.B.Saunders Company KEY WORDS: ear, reconstructive surgery, grafts, flaps, implants

While congenital deformities usually present the most difficult ear reconstructive challenges, defects from the excision of tumors can also pose some interesting restoration problems. Oncological auricular resection usually creates partial defects of skin a n d / o r cartilage, and one has the advantage of beginning with a relatively normally shaped and positioned ear. Despite these advantages, the multiple convolutions and depressions of the ear combined with the usually firm fixation of skin to the underlying cartilage makes simple primary closure of many excised tumors often difficult without significant esthetic distortion of the ear. The goals of oncological auricular reconstruction would seem to be preservation or restoration of the preoperative ear, including symmetry with the opposite ear. However, given that both ears are rarely viewed simultaneously in any facial view and may be partially or completely covered by hair, the size, position, and orientation of the ear to the scalp and anterior face may be more important than an absolute recreation of the architecture of the opposite ear. Often, given the older age of most patients with auricular pathologies, eyeglass support by the helical root or enough lobule for earring wear may be the only functional concern. From a structural standpoint, the ear is often described as a step-wise progression of layers beginning inferiorly at the conchal floor and progressing upward to the scaphahelix and helix. To the casual eye, this framework essentially creates an outline of three curved lines: an outer elongated C-shape beginning from the helical root to the lobule; a central near-parallel curvilinear line from the crura to the antitragus; and an opposing distorted Ushaped line from the antitragus to the tragus 1 (Fig 1). Thus, From the Division of Plastic Surgery, Indiana University School of Medicine, Indianapolis, IN. Address reprint requests to Barry L. Eppley, MD, Indiana University School of Medicine, 702 Barnhill Drive, #3540, Indianapolis, IN 46202. Copyright 9 1999 by W.B. Saunders Company 1071-0949/99/0604-0007510.00/0

the pertinent skin-cartilage components that are necessary to make a recognizable ear are the helix, tragus, antitragus, and concha as is well demonstrated from congenital microtia repair (Fig 2).

AURICULAR PATHOLOGY Overwhelmingly, tumors of skin origin comprise almost all of the auricular pathologies, with squamous cell carcinomas being the most common (>50%), followed by basal cell carcinomas (30% t o 40%), and less frequently, melanomas (•5%). 2'3 The presentation of basal and squamous cell carcinomas on the helical rim and antihelix is common given their unprotected position on the ear with continuous exposure to the sun and other elements. The absence of subcutaneous tissue in the ear allows for the potential of early perichondrial involvement. However, the perichondrium usually acts as a barrier against direct invasion into the cartilage and often directs tumor spread laterally. Cervical lymph node involvement is very rare in basal carcinoma. However, a thorough examination of the neck should be done in squamous cell and melanoma, because up to one third of patients will have nodal spread. 6

RECONSTRUCTION Reconstructive options can be categorized by either the characteristics and location of the ear defect (eg, partial or full-thickness or upper, middle, or lower third of the auricle) or the type of surgical technique employed. Either approach is a valid method for selecting the type of reconstruction, but to avoid duplicity in their description, surgical techniques will be reviewed from the simplest to the most extensive ablative ear defect.

SECONDARY HEALING Because of the excellent vascularity of the head and neck region and its high resistance to infection, almost all facial

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there is relatively little tendency for contracture even with large resections (Fig 4). Combined with the absence of any significant fat between the dermis and perichondrium, this allows an ear reconstruction that is not depressed and is confluent with the surrounding skin. For best match of color and texture, skin grafts should be full-thickness, non-hair-bearing, and harvested from either the posterior surface of the ear, postauricular sulcus, or lateral neck. When cartilage is exposed without perichondrium, a skin graft may take if the amount of cartilage exposure is limited and adequate soft tissue contact is available such as in small excisions. An alternative strategy is to delay skin graft reconstruction until sufficient granulation tissue develops. However, a preferable approach would be to electively remove cartilage to expose the raw surface of the dermis on the opposite side of the ear. This is best done in concave areas such as the concha or triangular fossa, which are nothing more than simple hollows. This technique can also be performed on the helical rim, but there will be a resultant notch deformity.

COMPOSITE GRAFTING

Fig 1. The three outlines of the cartilage framework make an ear recognizable.

wounds including those of the ear will heal by secondary intention as was initially described by the work of Mohs. 4 This process obviously takes longer than surgical reconstructions and exacts a price of eventual scar contracture. The amount of scar contracture, however, varies according to the anatomical region of the ear involved and the characteristics of the excised w o u n d bed. Small superficial resections will heal with minimal to no esthetic distortion in almost all ear areas. The larger (>1 cm) and deeper the excision, the greater the contraction will be, particularly if there is loss of cartilagenous support. Generally, wounds on c o n c a v e ear surfaces will heal better and more esthetically acceptable than those on c o n v e x surfaces. 5 Given the relative simplicity of many surgical closures, however, secondary healing is limited to those patients who are unable to tolerate or do not desire any form of further surgery. When cartilage is exposed, granulation tissue is slow to develop, and with the risk of cartilage infection or necrosis, surgical reconstruction is indicated.

SKIN GRAFTING Skin grafts have great versatility in ear reconstruction. Because they are adaptable to even very concave or convoluted surfaces, they work very effectively in those superficial excisions that leave perichondrium (Fig 3). Because of the strong support of the underlying cartilage, 276

Like the nose, composite grafts of skin and cartilage can be used to restore small defects of the ear. The best selection for this technique are defects of the helical rim that are 1.5 cm or less in width to optimize take and prevent secondary atrophy of the central regions of the transplanted graft. 6 The graft is harvested from the scapha or helix of the opposite ear, and the excised defect is converted to a through-and-through wedge by removing the underlying skin and cartilage. The graft is then inset with maximal contact to vascularized skin on both edges. In defects of this size, however, other methods of direct closure may be simpler and eliminate the need for manipulation of the opposite unaffected ear. One of the advantages of composite grafting would be to allow adjustment of the height of both ears. By a well-measured graft harvest, the resected ear can be restored (with a slight reduction in height from normal), while the donor ear can be slightly reduced to match the opposite side. Most patients, however, are not that discriminating to demand absolute symmetry of both auricular heights. Larger defects may be reconstructed with this technique by reducing the bulk of one surface of the composite graft. The posterior skin and cartilage are removed from the graft medial to the new helix and inset into the defect. Vascular ingrowth is achieved by either having a defect that has preserved the postauricular skin or advancing a postauricular skin flap in full-thickness defects to serve as the recipient bed for the remaining anterolateral portion of the composite graft. 12

DIRECT CLOSURE The tight adherence of the skin to the underlying cartilage limits the ability to directly approximate many ear defects. If the defect is small and the excision lies parallel along the helical rim, the surrounding skin may be approximated with only slight flattening of the rim contour. For larger defects along the helical rim that are full-thickness, the ear segments may be brought together in a classic V-shaped or BARRY L. EPPLEY

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Fig 2. Congenital microtia repair (A = preop at age 6; B = postop at age 8 after a four-stage reconstruction).

wedge closure (Fig 5). Because of the stiffness of ear cartilage, closure of larger wedges will distort the ear by pulling it forward around the defect, creating an iatrogenic cup-ear deformity. This is particularly manifest in the upper half of the ear, which has more inherent curvature. This can be reduced by extending the full-thickness excision deeper into the ear, often crossing the antihelix into the concha, to close down the angle of closure. Another technique for closure of wedge excisions is to selectively remove additional triangles of tissue along either one or both limbs of the excision. This is done either along the antihelical rim or concha and alleviates some of the tension of closure at the price of an overall smaller, but normally appearing, ear. The design and location of these triangular excisions is up to the tailoring of the surgeon and will vary somewhat depending on which area of the ear is involved.

Numerous local flaps have been described for ear reconstruction that are based either on tissue within the existing ear structure or adjacent non-hair-bearing skin from the postauricular sulcus, mastoid, or upper cervical regions. These are almost always random skin or skin-cartilage flaps that can be advanced, rotated, or rolled to restore the missing ear part. The following basic flaps are the most commonly used but are not inclusive of all methods.

based on the original description of Antia and Buch 1~is an extremely reliable method with numerous variants. While originally described for upper-third ear defects as an inferiorly based advancement flap, it works equally well, if not better, for more inferior helical rim defects. For middlethird defects 2.5 cm or less in size, the remaining lower portion of the helix, antihelix, and lobule is transferred superiorly based on the vascular supply from the posterior skin (Fig 6). This technique takes advantage of the helical mobility obtained after its release from the scapha. An anterior cut is made through skin and cartilage along the helical rim or within the scaphoid fossa but not through the posterior ear skin. Incisional release is carried into the ear lobule as necessary for the amount of advancement needed. This maneuver is very effective, because the lobule lacks cartilage, which allows a large amount of stretch and adapts well to a reduction in size. u When used for inferior transfer of the residual helix and antihelix for more superior helical defects, incisions must be carried around the apex of the anterior helical crus, creating a V-pattern of skin and cartilage. Again, the posterior skin remains intact, although a portion of it can be excised for even greater mobility of the flap. This allows closure in a V-Y advancement pattern. In larger defects, opposing superiorly and inferiorly based helical advancements can be done, which lessens the esthetic distortion that may occur when either flap is used alone. 12

Helical Advancement

Postauricular Flaps

For defects of the lateral or helical portion of the ear, the well-known and described helical advancement technique

Postauricular skin, based either superiorly or inferiorly, can be transferred to resurface or reconstruct ear defects. In

LOCAL

FLAPS

AURICULAR RECONSTRUCTION

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Fig 3. Skin grafting of ear defects. Excellent results are obtained on all ear surfaces with cartilage and perichondrial support with little risk of contracture.

its simplest form, postauricular skin fashioned into a rolled tube can be advanced to restore a helical rim. 12,13 In a staged procedure, the lateral margins of the ear defect are initially sewn into the postauricular skin. At a second stage, the posterior edge of the postauricular skin with the desired amount of skin needed to create the helical rim is released and the postauricular defect either primarily closed or skin grafted (Fig 7). When the excised defect extends beyond the helical rim, a larger postauricular skin flap is needed with a broader base and the need for a cartilage strut incorporated as part of the flap inset to resist collapse and secondary ear distortion. In a more eloquent use of this concept as a transposition flap, a cutaneous tube, or flap can also be created with an axial blood supply based on the postauricular vessels. In one or two subsequent stages, the skin is transposed into the helical defect with an initial superior attachment, followed by an inferior release and inset. 14,15 An island of postauriuclar skin can be transferred into the concha when both skin and cartilage have been removed. An island of skin is outlined around the postauricular sulcus, partly on the mastoid area and partly on the postauricular region. Skin incisions are then made entirely around the outline of the flap, preserving a vertical band of subcutaneous tissue at the ear-mastoid groove. This becomes the vascular pedicle and allows the skin island to be passed onto the anterior surface of the ear for reconstruc-

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tion of the conchal defect (Fig 8). The donor defect is closed primarily.

Infra-auricular/Cervical Flaps A variety of defects of the lower one third of the ear including the lobule can be satisfactorily reconstructed by adjacent skin flaps. The laxity of the upper neck skin, especially in the older patient, compared with the postauricular skin over the mastoid, makes flap transfer slightly easier. The trade-off for easier skin movement of upper neck skin is that scars and skin grafts of the donor sites are more visible. Small wedge excisions or a reduction in the size of the lobule is esthetically well tolerated as long as enough lobule remains to create a clear separation from the antitragus and hangs below the lower border of the concha cavum. While replacement of the lobule can be done by a one-stage transfer of a superiorly based (auricular) skin flap, most excisional defects have a free-standing edge rather than the defect already scarred to the neck. 12 Therefore, a two-stage approach to transfer both skin and cartilage is devised. Initially, a contralateral conchal cartilage graft is inserted in a soft tissue pocket beneath the lobular defect and the superior skin edge attached to the lower edge of the lobular defect. During the second stage, the chondro-cutaneous unit is released and its medial surface skin grafted 14(Fig 9).

BARRY L. EPPLEY

Fig 4. Skin graft reconstruction of the entire ear in a 64-year-old male with a history of congenital hemangioma (A --- preop; B = postop).

Temporoparietal Flap A fascial flap from the superior area above the ear based on the temporal vessels is an easily raised and reliable method of providing vascularized cover for any portion or all of the ear. It is commonly used in combination with splitthickness skin grafts for coverage of cartilage or synthetic frameworks in major or complete loss of the ear, when postauricular skin is unusable due to scarring from excision or burn injuries, and as a method of salvage for exposed frameworks. While it is a more extensive procedure with the inherent risks of a temporal scar and possible thinning of hair over the donor area, the temporoparietal fascial flap offers a one-stage approach to any size ear defect. When other methods of ear reconstruction are available, they should be used first, always reserving this fascial flap as a potential salvage method.

TOTAL AURICULAR RECONSTRUCTION When the entire ear is removed as a result of cancer, autogenous treatment options are often limited due to skin graft or flap coverage over the mastoid, as well as the frequent use of postresection radiotherapy. The classic technique of autologous reconstruction as is well described for microtia usually does not apply in oncological resections because of these tissue limitations, as well as the typical older age of the patient, who may not desire an extensive reconstruction requiring multiple stages. Traditionally, therefore, an ear prosthesis is used and is held into

AURICULAR RECONSTRUCTION

position by a variety of skin adhesives. While the artificial ear can be crafted as a beautiful replication of the opposite ear (Fig 10), its retention on the side of the head is variable and is adversely affected by wet and windy weather, high-temperature work conditions, strenuous physical activities, patient compliance with skin hygiene, and skin reactivity to the adhesives. Under these circumstances, the use of an osseointegrated-retained ear prosthesis is a preferable alternative and offers numerous advantages in these patients, including ease of placement, predictable retention, improved esthetics, increased life span of the prosthesis, and elimination of continuous irritation to the skin.7,8 Since 1979, metal implants have been placed in the mastoid region for retention of an ear prosthesis. 9 The success of this procedure is based on successful integration (lack of a fibrous tissue interface) between the metal (titanium) implant and the mastoid bone and tolerance of the surrounding skin to the penetrating metallic fixture. This is achieved by a two-stage procedure in which two or three titanium implants are initially placed under lowspeed drilling to prevent bone damage. This is followed by a 3- to 6-month healing period to allow direct bone-implant bonding. A second stage consists of implant exposure and the attachment of percutaneous fixtures onto which the final ear prosthesis will be attached. If the mastoid region around the implants has not been previously skin-grafted, this is often clone at the same time. It is imperative that the thickness of the skin around the implants be less than the

279

Fig 5. Primary closure of wedge excision of helical malignancy (A B = primary closure of wedge excision).

height of the collar around the fixture to prevent hygiene problems and chronic skin irritation. The skin flap over the implants can also be thinned to achieve this, but a splitthickness skin graft is usually more efficacious. Once the fixtures are exposed, the anaplastologist fabricates the final prosthesis, which may be attached by either a snap-fit or magnetic attachment (Fig 11). This alloplastic approach to ear reconstruction has a significant long-term retention rate, even in irradiated bone, with extensive experience in Canada, Sweden, and the United States.

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excision of melanoma of helix and preauricular lesions;

GENERAL RECONSTRUCTIVE PRINCIPLES Amidst the variety of ear-reconstruction techniques presented, certain conceptual and technical principles are worth following, including: 1. In reconstruction of an ear defect, the fundamental approach is either reduction or replacement. In assessing any ear defect, think of whether a smaller but normaMooking ear is acceptable or whether replace-

. Fig 6. Classic depiction of Antia-Buch's helical advancement technique.

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BARRY L. EPPLEY

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Fig 7. (A) Postauricular skin flap advancement for helical rim restoration (anteriorly-based). (B) Outer ear loss secondary to horse bite. (C) Postauricular skin advancement after tissue expansion (posteriorly-based).

ment of the missing parts is better. While a reductive approach can be achieved in one stage and is simpler, tissue replacement usually requires multiple stages and is more complex. 2. Preservation or restoration of the postauricular sulcus and external auditory canal are major functional areas of reconstruction.

The ability to gather and transmit sound to the tympanic membrane and provide support for visual or recreational eyeglass wear are the only significant functional objectives of ear reconstruction. The majority of the intricacies of the ear framework including the lobule are decorative. In general, do not sacrifice tissue or induce scarring from the postauricular sulcus or concha

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Fig 8. Postauricular island flap for conchal reconstruction.

AURICULAR RECONSTRUCTION

281

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Fig 9. Lobule reconstruction by infra-auricular/cervical flap transfer, which can be used with a cartipostoperativelags graft to eliminatecontrac. ture.

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Fig 10. Prosthetic ear fabrication produces a beautiful replica of the normal or opposite ear.

Fig 11. (A) Osseointegrated titanium implants secured to mastoid after removal of entire ear secondary to melanoma. (B) Total ear prosthesis held in place by magnetic attachments to titanium implants. 282

BARRY L. EPPLEY

s y m b a for reconstructing other ear regions unless a m e t h o d is p r o v i d e d for simultaneously reconstructing these areas as well.

3. Restoration of ear cartilage support after resection is usually not necessary in concave hollows. Cartilage s u p p o r t of the shape and position of the ear is maintained primarily b y the shape and length of the helical rim and antihelix. Concave hollows such as the concha and triangular fossa a d d interesting architecture to the ear b u t little to structural support. They, therefore, m a y be replaced b y soft tissue only.

4. Ear cartilage repair should be approximated by sutures. The elastic cartilage of the ea,." does not heal with cartilagenous i n g r o w t h but by the d e v e l o p m e n t of fibrous scar between the cut cartilage edges. Therefore, cartilage edges should be sutured with an u n d y e d slowly resorbing or clear p e r m a n e n t suture for a more secure closure.

5. Full-thickness skin grafts are preferred over split-thickness grafts. Because of the paucity of subcutaneous fat on the anterior surface of the ear, a g o o d thickness m a t c h is obtained with full-thickness skin, thus avoiding contour depression of the reconstructed area.

SUMMARY The goals of auricular reconstruction after t u m o r excision are to obtain a functioning a p p e n d a g e on the side of the head that is as n o r m a l as possible in position, size, and contour, in decreasing order of importance. A variety of basic techniques to achieve these goals has been described including secondary healing, skin grafts, direct closure,

AURICULAR RECONSTRUCTION

local flaps, and alloplastic reconstruction d e p e n d i n g on the location and size of the excised ear segment. W h e n p r o p erly selected, these techniques have been p r o v e n to achieve successful ear-reconstruction results with limited complications.

REFERENCES 1. Tolleth H: A hierarchy of values in the design and construction of the ear. Clin Plast Surg 17:193, 1990 2. Songcharoen MD, Smith RA, Jabaley ME: Tumors of the external ear and reconstruction of defects. Clin Plast Surg 5:447,1978 3. Menick FJ: Reconstruction of the ear after tumor excision. Clin Plast Surg 17:405,1990 4. Bernstein G: Healing by secondary intention. Dermatol Clin 7:645, 1989 5. Zitelli JA: Wound healing by secondary intention. J Am Acad Dermatol 9:407, 1983 6. Brent B: Reconstruction of the auricle, in McCarthy JG (ed): Plastic Surgery, vol 3, Philadelphia, PA, Saunders, 1990,pp 2131-2146 7. Wilkes GH, Wolfaardt JF: Craniofacial osseointegrated prosthetic reconstruction. Adv Plast Reconstr Surg 15:51, 1998 8. Wilkes GH, Wolfaardt JF: Osseointegrated alloplastic versus autogenous ear reconstruction:Criteria for treatment selection. Plast Reconstr Surg 93:967, 1994 9. Tjellstrom A: Osseointegrated implants for replacement of absent or defect ears. Clin Plast Surg 17:355,1990 10. Antia NH, Buch VI: Chondrocutaneous advancement flap for the marginal defect of the ear. Plast Reconstr Surg 39:472,1967 11. Renner G, Templer J: Reconstruction of the external ear. Facial Plast Surg Clin North Am 4:491, 1996 12. Brent B: Reconstruction of the auricle, in McCarthy JC (ed): Plastic Surgery, vol 3. Philadelphia, PA, Saunders, 1990,pp 2133 13. Lewin M: Formation of the helix with a postauricular flap. Plast Reconstr Surg 5:542, 1950 14. Cheney ML: Local flaps in auricular reconstruction. Facial Plast Surg Clin North Am 5:371, 1997

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