Facial cutaneous reconstructive surgery: General aesthetic principles

JOURNA.L of the

AmeRICaN ACaDemy OF

DerMaTOLOGY VOLUME 29 NUMBER 5 PART 1

NOVEMBER [993

Continuing medical education Facial cutaneous reconstructive surgery: General aesthetic principles Bradley K. Summers, MD, and Ronald J. Siegle, MD Columbus, Ohio The performance of cutaneous reconstructive surger y requires understanding and application of many important principles. This a rticle reviews the critical factors to consider in the management of surgical wounds by second-intention healing, primary closure, skin grafting, and repair with local flaps. For certain defects, reconstruction with local flaps offers several advantages over other alternatives. Key concepts useful in flap choice and implementation are discussed, and surgica l techniques that maximize the aesthetic outcome of reconstructive surger y are reviewed. (J A M ACAD D ERMATOL 1993;29 :669-81.)

Skilled cutaneous reconstructive surgery requires an understanding and application of the key principles of anatomy, wound healing, basic excisional surgery with primary closure, skin grafting, and local skin flaps. This article reviews the important concepts that provide the framework for functional and aesthetic reconstruction of cutaneous surgical defects of the face, with emphasis on local skin flaps. With these concepts as guidelines, we will then review in a subsequent article flap reconstructive alternatives for each of the m ajor facial cosmetic units. The concepts and closures reviewed are primarily useful fo r skin and soft tissue facial defects up to approximately 4 em in diameter but may be applicable to larger and more complex defects.

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The CME articlesare made possi hIe through an educational grant from the Dermatological Division, Ortho Pharrna\.~~ ceutical Corporation. From the Department of Otolaryngology, The Ohio State University. Reprint requests: Ronald J .Siegle, MD, Associate Professorof Clinical Otolaryngology, Director, Mohs MicrographicSurgery and Dermatologic Surgery, The Ohio State University, 456 W, l Oth Ave" Columbus, OB 43210. Copyright @ 1993 by the American Academyof Dermatology, Inc. 0190-9622/93 $1.00 + .I0 16/2/50104

ORTHO

MANAGEMENT OPTIONS FOR CUTA NEOUS SURGICAL DEFECTS

Given a particular surgical defect, options for management may include primary closure, secondintention healing, skin grafting, or local tissue transfer with random-pattern or axial flaps. The choice depends on several factors and these must be evaluated for each patient and for each particular defect. A wound of the same location, depth, and dimensions in different patients can be managed in divergent ways depending on several variables. Important additional factors to consider include the availability and condition of adjacent tissue, the medical condition of the patient, patient des ires, and social factors (e.g., concern for cosmesis, ability to care for the wound, likelihood of follow-up). The surgeon's experience and personal preferences are also significant factors in the decision-making process. When considering the management options for a given surgical defect, there are four basic alternatives and four questions to be asked: What would be the expected result if the defect were not repaired (i.e., healing by second intention)? Zitelli and other authors':" have shown that second-intention healing can give excellent functional

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It is bestusedwhenthe closure can be accomplished with low tension, when the resulting closure is not excessively long, and when "dog ears" can be strategically positioned sothat the finalscar liesin a favorable skin line. Another management option shouldbe considered if primaryclosure wouldresult inexcessive tension ordistortion ofan anatomicunit. Long, linear scars that result from primary closure of larger wounds are easily noticed and should be avoided. What result would be expected if the wound were managed with a skin graft?

Fig. 1. Locations in which healing by second intention may give good to excellent cosmetic results. (Modified from Zitelli lA. Wound healing by second intention. 1 AM ACAD DERMATOL 1983;9:408-15.)

and cosmeticresults. It is best usedforsmalldefects that are superficial and in concave areas(Fig. 1). It may also be used for larger defects in locations in which the contraction associated with healing will not lead to functional or cosmetic deformity of adjacent tissue. Guiding sutures are useful in certain situations to direct tension awayfrom an anatomic structure that might be deformed or malpositioned by wound contraction.' Second-intention healing may alsobe the option of choice if thereis a concern about tumor recurrence. The major disadvantage of this option is that in many instances the cosmetic result willbe unacceptable. The longerhealingtime and wound care requirements arealsodisadvantages and should be discussed with the patient. What would be the expected result if the wound were closed by primary repair?

Side-to-side or primary closure is often the simplest and best approach. It allows quickreconstruction, minimal incisions and scars, and rapidhealing.

Skin grafts are an important and necessary tissue sourcefor reconstructive surgeryof the face.f They may at timesbethe treatment ofchoice, meetingthe functional and aestheticchallenge posedby the surgicaldefect. At other timesthey are usedby default because the lack of adjacent tissue precludes primary repair or use of a local flap. Of the three commonly used grafts (full-thickness, split-thickness, and composite), the full-thickness graft is the most usefulfor facialreconstruction. This typeof graft is often the treatment of choice for reconstruction of thenasaltip andlower eyelid and isusefulfor defects of the nasal alae and auricle, and for larger defects ofthe templeand forehead." Becausegrafts prevent significant woundcontraction, they are often a better functional choice for some defects than healing by second intention. In addition, if donor tissue matches recipient site tissue well, full-thickness grafts may provide a better cosmetic result than second-intention healing. They can also give a better resultthan a poorly plannedlocal flapthat results in distortionor contour deformities. Split-thickness grafts are used primarilyfor large wounds or in situations in which tumor surveillance is of primary concern. They are cosmetically a compromise and functionally limiting if wound contraction is a concern. They allow a significant degreeofwoundcontraction, but much less than second-intention healing. When considering the use of a skin graft, the location of the defectshould be evaluated first. Is it a site whereprimary closure or a flap are not possible becauseof a lack of recruitableskin? What are the size and depth of the wound? Is there sufficient soft tissueandvascular tissuetosupportthe graft? If not, would a delayed graft be better to allow formation of granulation tissue? What color and texture does the localskinhave?Next,possible donorsitesshould

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be considered. Commonly used sites are the preauricular and postauricular areas, the supraclavicular and lateral aspect of the neck, the upper eyelid, and the melolabial crease. A site should be sought with sufficient redundant skin that will acceptably match the size, color, texture, thickness, degree of sun damage, vascularity, and sebaceousness of the original skin of the defect site. With properly chosen defects and donor sites, skin grafts are often successful, both functionally and cosmetically. However, disadvantages of skin grafts must also be considered. Foremost among these is that the color and texture match of grafts may not be equal to that achieved with primary closure or a local flap. Skin grafts may heal with a patched appearance. They require an additional surgical procedure at a distant site. (An exception is Burow's graft. 8 ) Although most patients are pleased with the appearance of the healed graft, in some cases adjunctive procedures (dermabrasion, intralesional steroids) may be necessary later to improve its contour and/or color.?

What result would be expected with the use of a local flap? After second-intention healing, primary closure, and skin grafting are considered, the use of a local skin flap to manage the defect should be evaluated next. Would there be a superior result if a local skin flap were used? Functional requirements may dictate the use of a flap in certain situations. Wounds overlying bone or cartilage where periosteum or perichondrium have been removed do not have sufficient vascular support for a graft. Deep or full-thickness wounds can be reconstructed with flaps to restore tissue bulk lost in lesional extirpation. In wounds in which direct sideto-side closure would cause distortion of an anatomic unit such as an eyelid or lip, properly designed flaps allow redirection and/or redistribution of closure tension. Local flaps are often cosmetically superior. Scar "camouflage" is a major advantage of flaps. They can usually be designed so that some or all incisions are placed within normal facial lines such as the junction lines between facial units, or within or parallel to relaxed skin tension lines (see later). The irregular scar pattern achievable with flaps is often less noticeable than a long linear scar from a primary closure. Tissue protrusions (standing cones, "dog ears") can be repositioned and removed in less no-

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ticeable locations. Importantly, flaps allow reconstruction with adjacent tissue of similar characteristics of color, texture, thickness, sebaceousness, and degree of actinic damage. Although the use of local flaps has many advantages, there are also some disadvantages and potential complications that must be considered.l'l 11 A flap requires additional incisions and tissue movement, which increases the risks of postoperative bleeding, hematoma, pain, and infection. If the incisions cannot be hidden well in skin tension lines or natural creases, they may leave unsatisfactory scars. There may be an increased risk of flap failure from vascular compromise or infection in patients with underlying medical problems such as bleeding disorders, peripheral vascular disease, diabetes, or immunosuppression. Smoking also significantly increases the risk of flap failure. 12 A flap may result in anatomic distortion. This may be seen as local deformity or as asymmetry of the face. If flaps are poorly planned and/or executed, significant functional impairment may occur such as ectropion, nasal obstruction, and eclabion. Where there is a concern regarding the adequacy of tumor resection, a flap may unnecessarily obscure the surgical site and adjacent tissue and delay the observation of recurrence.

Surgical defect management: General guidelines When wound management options for facial cutaneous reconstruction are evaluated, the following approach is recommended: 1. Consider the defect. Which option will give acceptable results considering structure, function, cosmesis, and the need for tumor surveillance? Is there a choice that will clearly be superior? If not, the simplest choice is usually the best choice. A combined approach (i.e., flap and graft, flap and secondintention healing) may be best in some cases. 2. Consider the patient. The wound management choice made after considering the defect may be altered by personal or medical variables such as cosmetic consciousness, concurrent medical problems, the need for further surgery, and the ability to care for the wound. 3. Discuss the options and your preferred choice with the patient, and then allow the patient to be an active participant in the final decision.

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Reservoirs of excess tissue

Fig. 2. Reservoirs of excess tissue.

BASIC CONSIDERATIONS FOR THE USE OF LOCAL FLAPS: WHICH FLAP DO I USE?

When use of a local skin flap is considered for facial reconstruction, there are four determinationsto be made. First, consider the sources of recruitable tissue. When a tissue source has been defined,think of possible mechanisms of tissue movement (advancement, rotation, transposition). Next, thoroughly evaluate the effectsof movingthe tissueinto the defect. Finally, determine whether the tissuecan be mobilizedand repositioned so that the finalscars are acceptably hidden or camouflaged. It is crucial to confirmthe presenceof tumor-free margins before proceeding with flap reconstruction if a malignant lesion has been excised.P This is of greater concern when flapsare used rather than primary closure or skin grafting becausenormal tissue orientation may be altered by flaps. Margin control may be accomplished by a variety of methods. Each offers different advantages, disadvantages, and degrees of accuracy.!" If accurate and immediate pathologic examination is not possible, delayed reconstruction should be considered.

Locations in which extra skin commonlymay be found includethe temple, glabella,lowerand lateral cheeks, preauricular folds, "jowls," neck, and nasolabial folds (Fig. 2). In addition tD these sites, within the wrinkles and relaxed skin tension lines there may alsobe a significant amount ofrecruitable skin, depending on age andthe elasticityand degree of wrinkling of the patient's skin. I5 In consideration ofthe tissuesourcea keyconcept is the principle of cosmetic units and subunits. A cosmetic unit is a major structural unit of the face that shares similarskin characteristicsof color, texture, thickness, elasticity, pore density and size, hairiness, and sebaceousness.l'v!" Synonyms include anatomic, regional, topographic, or aesthetic units. The major cosmetic units are the forehead, temples, cheeks, eyelids, nose, upper and lowerlips, chin, and ears. The linesseparating these units are known as contour lines or junction lines (Fig. 3). Cosmeticunits may further be divided into subunits that are evenmorespecifically alikein skintype(Fig. 4). Theseunits are importantbecausetheydefine the area of priority for borrowing skin for flap development. In most casesdefects shouldbe reconstructed with tissue from the same cosmetic unit or subunit to optimizethe match. Next in priority would be to borrowthe skin from an adjacentunit, suchas cheek skin for a lateral lip defect. There are often preferred donor sites for defects in a given cosmetic unit or subunit. For example, lateral forehead defects can usually be most easily reconstructed with skin of the temple. However, there isinterpatient variability, and each patient and each defect shouldbe evaluatedseparately. In some cases there may be two or more areas of available skin.In thesesituations, the choiceof donorsitemay be made based on several variables, including qualitative match, preferred location of the flap base (often inferior or lateral), and local anatomy (risk for injury to a significant nerve or vessel). A major advantageof flaps isthat they allow reconstruction with IDeal skin, whichprovides the best possible match. This goal can best be achieved by recognizing and incorporating the principle of cosmetic units and subunits when choosing donor skin for flap development. Tissue movement: How can the tissue be repositioned to fill the defect?

After a tissue source or sources are defined the next consideration isthe wayin whichit can be mo-

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673

temporal hairline [para med ian foreheadl

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Fig. 3. Facial cosmetic units (capital letters), forehead subunits (brackets), and junction lines, bilized and repositioned to fill the defect. When a flap is cut, elevated, and positioned in its new home, various movements oftissue result not only from flap placement but also from pull on surrounding tissues. To understand better some of these movements, we will review some definitions used for flap dynamics. 18 The first is primary movement. This is the actual movement of the flap into the surgical defect, also known as the primary defect. The primary movement of the flap from donor site to the defect creates a new defect at the donor site called the secondary defect. Secondary movement refers to the movement of tissue surrounding the primary and secondary defect in reaction to the movement of the flap. The three classic types of primary tissue movement are advancement, rotation, and transposition. Flaps are categorized, in part, according to the predominant type of movement used in their implementation. It is important to remember that flaps often incorporate more than one of these types of movement. As skill increases in flap design and implementation, it becomes evident that varying the relative degree of advancement, rotation, or transposition may significantly alter key elements of the

reconstruction including closure tension and the effect of flap movement on surrounding tissues. This advanced level of understanding of tissue biomechanics and movement allows both creativeflap design and optimal functional and aesthetic outcome. In pure advancement flaps, primary tissue movement isfrom donor source to defect ina straight line, whereas secondary movement occurs in the opposite direction (Fig. 5). They are best used in areas in which the tissue is relatively stretchable and redundant and when incisions can be placed in straight creases or skin lines. Advancement flaps do not significantly decrease closure tension of the primary defect when compared with direct side-to-side closure. Their primary advantage is that they allow redirection of incisions and tissue redundancy ("dog ears") to more favorable sites. Increasing flap length does not significantly increase tissue mobility more than additional undermining.l? In rotation flaps, primary movement of tissue isin an arc around a half-circle defined by the defect and the length of the flap. 20 Secondary movementoccurs around the arc in the opposite direction (Fig. 6). The curvilinear scars that result from rotation flaps can

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Journal of the American Academy of Dermatology November 1993

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- - - -glabella - - - root lateral ridge - - lateral sidewall

nasofacial sulcus

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Fig. 4. Nasal cosmetic subunits and junction lines.

be hidden best in junctions between facial cosmetic units or where the skin tension lines are of a similar shape and direction. In contrast to pure advancement flaps, rotation flaps redirect and redistribute some tension from the primary defect to the secondary defect. In general, as the length of a rotation flap increases, the tension of closure of the primary defect decreases. Two alterations of the basic design of rotation flaps allow additional tissue movement and are useful in some situations.P A back cut into the pedicle lengthens the arc of rotation of the flap and adds a component of advancement (Fig. 7). This must be done cautiously, as it may potentially compromise the vascularity of the flap. A second useful modification of rotation flap design is to increase the

height of the leading edge of the flap relative to the height of the defect. This moves additional tissue to the primary defect and can reduce tension of the primary defect closure. However, it also increases the size of the secondary defect. Transposition flaps use primary movement of a rotation type to mobilize tissue from the donor site to the primary defect with the transfer occurring over an intervening segment of intact skin. These flaps are more efficient at moving tissue than advancement or rotation flaps; that is, they can move nearby or distant tissue and can do so effectively while remaining relatively small.'? In addition, when compared with advancement and rotation flaps, they generally have relatively smaller but more numerous

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of Dermatology

e. Fig. 5. Classic advancement flap, showing primary movement (solidarrow) and secondary movement (open arrow).

Summers and Siegle 675

[

Fig. 7. Rotation flapwith back-cut. This provides additional tissue movement by rotation and advancement. (Primary movement: solid arrows;secondarymovement: open arrows.)

.,',:/;\?:.: . Fig. 6. Rotation flap, showing shared secondary movement (open arrows) around primary and secondary defects. (Primary movement: solid arrows.)

incisions. Therefore they are useful in situations in which incisions are not easily placed in natural creases and a broken-line closure is desirable to camouflage scars. Perhaps the most important advantage of transposition flaps is that they can be designed to redirect nearly completely the tension of closure from the primary to the secondary defect. This also minimizes secondary motion of tissue immediately adjacent to the primary defect but increases it adjacent to the secondary defect (Fig. 8). These characteristics become especially useful in reconstruction of defects near free margins where distortion may easily oceur (see later). If tension redirection is a priority, oversizing the flap is recommended. Classic 60-degree rhombic flaps redirect tension 90 degrees from the direction of closure of the primary defect. Thirty degree transposition flaps redirect tension less and share closure tension between the primary and secondary defects? There are several other types of transposition flaps, and they vary in their design and goals for moving tissue, camouflaging incisions, and redirecting and redistributing tension of closure.P Effects of tissue movement

Once the donor sources of skin for flap development and the ways it can be moved have been deter-

k··:,,~K~ .... .. . . .

Fig. 8. Classic rhombic transposition flap. Note that mostsecondary movement(openarrows) occursadjacent to secondary defect as it is closed. (Primary movement: solid arrows.)

mined, the effects of moving that tissue into the defect should be carefully evaluated. The primary consideration here is one ofsecondary movement, or movement of tissue surrounding the primary and secondary defects in response to mobilizing, positioning, and securing the flap. The choice of appropriate flap repairs involves the ability to predict accurately secondary movement, and this requires an understanding of the forces of tension placed on adjacent and distant anatomic structures by closure of the primary and secondary defects. Can the primary and secondary defects be closed without distortion of surrounding tissues ? The long-term effect of tissue movement is also important. Scar contraction that occurs in the normal process of wound healing may result in delayed distortion. Close attention must be given to the free margins. These are the borders of cosmetic units that have no adjacent tissue and thus offer no resistance to opposing force. 24 The free margins of the face

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include the lips, the eyelids, the alar rim, and the helix. Flaps should be designed that either reduce or maintain baseline tension on free margins. For example, an advancement flap to reconstruct an upper medial cheek defect is best designed to incorporate tissue from a lateral rather than inferior donor site so that the tension of closure does not cause downward pull (secondary movement) of the lower eyelid. Oblique suturing and suspension sutures are techniques that are helpful to reduce or redirect tension away from free margins.P How are the effects of tissue movement determined? The skin surrounding the defect may be pushed, pulled, pinched, squeezed, and stretched. Much of this can be accomplished before anesthesia is injected. Undermining adjacent to the defect in all directions may help define the forces of tension more accurately. Important anatomic units and free margins should be tested for distortion by applying tension in the direction of the wound closure. The degree of eyelid laxity can be evaluated by the snap test, which is done by manually pulling the lower lid away from the globe and then releasing it. 26 The speed and degree of return to its baseline position may be a useful predictor of the tendency toward ectropion. A normal lower lid will return to its original position rapidly and cannot be pulled more than 10 mm away from the globe. The potential for the alar rim to elevate can be sensed by upward and inward pressure. Experience is important and helpful, but as with other aspects of cutaneous surgery, each patient and defect must be evaluated separately. The process of evaluating tissue movement and its consequence is ongoing and continues once the proposed flap has been cut and positioned. One should be prepared to "change gears" during a repair ifit becomes evident that cosmesis or function will be significantly impaired by adhering to the original plan. Scar placement: Favorable incision lines

The strategic placement of incisions so that the final scars are "camouflaged" or hidden within the natural lines and creases of the face is a major principle in flap design. Once a tissue source has been identified and the mechanism and effects of moving that tissue into the defect are considered, the most favorable lines of incision must be determined. The goal is to place most or all incisions in anatomic junction lines and!or skin tension lines. Junction lines Junction lines are the expected creases, folds, or demarcations between cosmetic units of the face.

Journal of the American Academy of Dermatology November 1993

We extend this concept to include also major lines that separate cosmetic subunits, such as the alar crease. Incisions placed within these junction lines will heal with acceptable and often imperceptible scars. Junction lines on the upper third of the face are the anterior (frontal) and temporal hairlines, the eyebrows, and the creases separating the glabella from the root of the nose and from the main part of the forehead. In the central part of the face, the prominent lines are the melolabial (nasolabial) folds, the alar creases, the nasofacial sulcus between the nasal sidewall and the medial cheek, and the infraorbital crease between the lower eyelid and cheek. The lower third of the face has the important junction lines of the philtrum, the vermilion-cutaneous junction of the lips, and the mentolabial crease. The side of the face is bordered by the preauricular crease. A less conspicuous junction line courses along the lower jaw and mandible and separates the cheek from the neck (see Fig. 3). As the various flaps available to close a surgical defect are considered, those that allow closure of the primary and secondary defects in junction lines should be given high priority. The reward is usually twofold because the resultant scars are fine and relatively hidden. In contrast, an incision that crosses or displaces a junction line often results in scars that are both easily noted and, at times, disfiguring. Skin tension lines In addition to junction lines, there are other facial lines in which incision placement and scar creation result in optimal aesthetic outcome. These lines have been described by many authors, and variability exists in their nomenclature, patterns, and proposed cause. This has led to confusion with regard to the importance of the various lines. To clarify this principle, we will discuss some of the historical background concerning the description of these lines and then describe ways in which to utilize them. Early investigators described lines of tension based on cadaver skin studies.F' The most famous of these was Karl Langer, an Austrian anatomist who in 1861 reported the pattern of lines that were noted after puncturing the skin of cadavers with a "sharp spike symmetrically ground to a conical point." The puncture holes were elliptical rather than round, and by connecting the long axes of these wounds a series of lines was determined and mapped. 28,29 "Langer's lines" became a standard for incision orientation for the next several years. In the mid-1900s others examined skin tension lines in living subjects with other techniques and

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emphasized the natural wrinkles and creases and the force of underlying facial muscles in their formation. 30, 31 More recently, Bulacio as well as Stegman described patterns of skin tension lines on the face based on wound elongation after a series of circular excisions on the face. They also mapped the areas in which tension was uniformly distributed so that the wounds maintained the circular shape of the excision. 32, 33 In 1962 Borges and Alexander'" published their concept that surgical incisions should parallel the "relaxed skin tension lines." As described by Borges, these are not clearly visible lines of the skin such as wrinkle lines, but rather are a series of lines that indicate the directional pull that exists in relaxed skin. He attributed the tension producing these lines to the tenting effect of skin over the underlying bony, cartilaginous, and soft tissue structure, and not to the contraction of underlying muscles. He thus distinguishes these lines from the lines of expression and wrinkle lines, although in many areas of the face the patterns are identical. In addition, he notes that "the relaxed skin tension lines are very much the same in all individuals" and that they can be determined by noting the "furrows and ridges" that are formed by pinching the skin.35, 36 Despite several attempts to define a single pattern of favorable incision lines, there is no consensus and in practice each patient must be evaluated individually for lines that guide incision placement. The pattern of lines, wrinkles, and creases present in a person is probably caused by a combination of factors, including the static and kinetic tension caused by underlying structures, muscle contraction, and gravity. The inherent structure of the dermis and subcutaneous tissue and its elasticity and extensibility are also important, as evidenced by the effects of aging and actinic damage on the pattern of facial skin lines.37 Although the skin tension lines vary from person to person, in general they run perpendicular to the underlying facial muscles (Fig. 9). Their direction is more predictable in certain locations such as the forehead, the cheek, the eyelid, and lips. The lateral canthal area and temple, the chin, and the nose are less predictable. Some areas, such as the nasal tip and the lobule of the ear, are neutral and skin tension lines are not discernible. How are the skin tension lines found? Helpful maneuvers include pinching the skin, having the patient contract facial muscles, and using obliquely oriented lighting. In younger patients the lines are

Summers and Siegle 677 sometimes not easily discernible and it may be necessary to orlent incisions based on the expected lines. If a lesion obscures the lines or if they become unclear after excision, it is often helpful to examine the opposite side of the face. Undermining in all directions around a defect usually allows the tissue to assume the most favorable direction of closure based on local tensions and a favorable incision line may become evident after doing so. It is important to examine the patient closely for the pattern of lines present before starting the surgical procedure because local anesthetic injection and excisionof tissue may alter them. Marking the skin tension lines before the procedure begins may be useful. This helps in both incision planning and intraoperative decision making if the original surgical plan needs to be modified. Lines other than the predicted or present skin tension lines include wrinkle lines and lines of facial expression. These are often, but not always, useful for hiding scars. The glabellar wrinkle lines are useful for hiding scars when utilizing glabellar tissue for nasal or medial canthal defects. The vertical wrinkle lines sometimes present on the forehead may be used for incisions, but the horizontal lines corresponding to the relaxed skin tension lines are preferred. Facial muscle contractions (smiling, whistling, tightly closing the eyelids) are often helpful to define the skin tension lines but may accentuate lines of expression that are not favorable for incision placement. For example, in many persons smiling forms a horizontal crease on the upper lip that is clearly not a favorable direction for incision. In summary, the decision-making process for possible use of a local flap should include careful consideration of where tissue may be borrowed, how it can be repositioned, what the immediate and long-term effects of moving that tissue will be, and how scars may be hidden. If there are no satisfactory solutions for these general considerations, other reconstructive alternatives as already discussed should be considered. SURGICAL TECHNIQUES THAT MAXIMIZE AESTHETIC OUTCOME

By using the aesthetic principles that have been discussed, the surgeon is in an optimal position to select the best flap for a particular defect. However, selecting the best flap and proceeding with incision and development of it does not guarantee the outcome desired by the patient and the surgeon. In addition to the use of basic cutaneous surgical skills,

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".

Fig. 9. Skin tension lines (left) and facial muscles (right). Lines are usually oriented perpendicularly to muscles.

several surgical techniques are critically important to achieve optimal aesthetic and functional results. Several of these will be discussed. The suspensionsuture has many important uses in flap surgery.25, 38 Appropriately placed suspension sutures can reduce closure tension at the wound edges. This minimizes the acute risk of vascular compromise and necrosisand scar spread long-term. They can redirect closure tension to more favorable directions, avoiding distortion of important functional or cosmetic structures. They can close dead space in defects and create concave contours, recreating natural creases and folds. They can minimize the long-term effectsof gravity that may lead to skin relaxation and scar spread. They are placed from the dermis of the base of the flap to the periosteum of

underlying facial bones, including the zygoma, frontal bone, orbital rim, nasal bone, and maxilla (Fig. 10). They may also be anchored to deep adherent fascia such as the deep temporal fascia. Permanent or absorbable sutures may be used, depending on the long-term goals of reconstruction. Because they are placed in or near the flap base, they add an element of decreased vascularity to the flap. To minimize the potential for reduced blood flow, they should be placed parallel to the vasculature of the flap and should not be used if flap viability is a concern. Wound edge eversion is critically important. The vertical mattress variation of the traditional buried suture is an effectiveway to maximize eversion.39, 40 As scars mature, the remodeling process leads both

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Fig. 10. Rotation flap for upper cheekdefect, with suspension suture to lateral orbital rim periosteum. In this instance, the suture reduces closure tension of primary defect (shaded area), preventing ectropion.

to shortening as well as to thinning or flattening. Thus the outcome of a wound sutured without some degree of wound edge eversion is often a depressed scar, which is more noticeable because of the shadows it creates. Depressed scars are more common in sebaceous skin such as the nose, medial cheeks, chin, and forehead, and in these locations, even more pronounced eversion is preferred. Key features of the buried vertical mattress suture include a slightly wider needle path than the traditional buried intradermal suture and placement of the suture so that it comes closest to the skin surface 3 to 4 mm from the skin edge (Figs. 11 and 12). Traditional vertical mattress surface sutures are useful to evert wound edges, but because they are removed within the first week they provide only temporary eversion. Interrupted sutures or running continuous sutures can also be placed to provide some eversion if the path of the needle is wider at the base of the stitch than at the top (flask-shaped stitch). However, the buried vertical mattress suture more effectively everts wound edges for a longer time. Suture marks are occasionally a problem in facial cutaneous surgery. They more commonly occur in younger patients, in more sebaceous areas, and on convex surfaces. Factors contributing to their formation include the type of suture used (suture reactivity), length of time sutures remain in place, the tension of surface closure, and the suturing technique. For most reconstructive facial cutaneous surgery, surface sutures can be removed in 5 to 7 days. Suture marks can be avoided by using the running intradermal suturing technique.t! This technique is

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Fig. 11. Traditional buried suture provides support but no eversion.

Fig. 12. Buried vertical mattress suture. Suture passes more superficially in dermis a few to several millimeters from wound edge, thereby creating wound edge eversion.

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680 Summers and Siegle

B

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B·; ·.··

Fig. ·13. Z-plasty with 60-degree flaps. Incision (scar) length (AB) is significantly increased.

especially useful on the cheek and forehead. It can be used if the deep closure has minimized tension at the surface. Nonreactive suture such as polypropylene monofilament is best, and it can remain in place for up to 3 weeks. Wound closure tape provides additional support and is left in place until the suture is removed. Several postoperative procedures may be useful to improve the final cosmetic result. Some areas, such as the nose, often will benefit from one of these procedures, and it is helpful to discuss this with the patient before surgery. Dermabrasion of scars ("scarabrasion") can be done at 6 or more weeks postoperatively to camouflage scars and to improve contour and color. 42, 43 Dermabrasion of the scar and several millimeters of surrounding normal skin is usually adequate. Occasionally, abrading an entire cosmetic subunit or unit is done to camouflage the scar better. Intralesional steroid injection may be used to flatten raised scars and to improve contours of flaps that have developed a pincushion deformity. Unacceptably thick or bulky flaps can be surgically thinned when it is clear that the normal maturation process will not accomplish the same result. This is performed by incising within the surgical scar adjacent to the bulky portion of the flap, elevating the

thickened portion, and thinning the dermal and subcutaneous tissue as necessary. After any created excess of skin is trimmed, the flap is repositioned and sewn in place. Procedures that camouflage scars by "irregularization" are also occasionally useful. 44 The Z-plasty is one of the most useful of these techniques.P Its basic design incorporates single or multiple transposed flaps that result in lengthening and redirecting of the original scar. It also "breaks up" the scar into smaller components in different directions that may be less noticeable. The angle of the flap determines the degree of lengthening, which is approximately 25% for 30-degree flaps, 50% for 45-degree flaps, and 75% for 60-degree flaps (Fig. 13). The lengthening of scars is particularly useful for flattening webs formed by contraction across concave surfaces such as the medial canthus and for correcting distortion of free margins caused by scar contraction. Another scar revision technique that may be used is the geometric broken line closure. This is designed as a series of irregular geometric shapes along both sides of the scar that interdigitate as multiple small advancement flaps . In contrast to Z-plasty, it does not lengthen the scar but creates an irregular pattern that effectively camouflages scars. 44 , 46 Complex defects that are large or involve more than one cosmetic unit present unique reconstructive challenges. A conceptual surgical technique that is useful in these situations is that of defect subdivision. 47, 48 For combined defects involving adjacent cosmetic units, each unit should be evaluated separately for the extent of tissue loss and the most appropriate way to repair that unit. Rather than use of a single flap or graft that may not adequately recreate normal contours and supply adequately matching skin for each cosmetic unit, a combination of local flaps and/or grafts may be used. These are sewn together at the expected junctions. For defects involving a single cosmetic unit that are relatively large and/or irregularly shaped, the defect can be mentally divided into two or more components and each of them closed with an appropriate flap or graft. This technique allows the surgeon to utilize best the concepts of appropriate donor sites, preferred mech anisms of tissue movement, avoidance of adverse effects of tissue movement, and favorable incis ion lines. In summary, use of the basic principles of aesthetics and function will assist the surgeon in choosing the most appropriate management option for

Journal of the American Academy of Dermatology Volume 29, Number 5, Part 1

cutaneous surgical defects of the face. If the choice is a local flap, the best flap can be selected by evaluating the potential reservoirs of excess tissue, mechanisms of tissue movement, effects of tissue movement, and sites for favorable incision placement. The final surgical result can be significantly improved when keysurgical techniques are used, including timely use of suspension sutures, wound edge eversion by buried vertical mattress sutures, select use of scar revision procedures, and defect subdivision for complex surgical wounds. REFERENCES 1. Zitelli JA. Wound healing by secondary intention. JAM ACAD DERMATOL [983;9:407-[5. 2. BeckerGD, Adams LA, Levin BC. Nonsurgical repair of perinasalskindefects. PlastReconstrSurg 1991;88:768-76. 3. PanjeWR, BumsteadRM, Ceilley RI. Secondary intention healing as an adjunct to the reconstruction of mid-facial defects. Laryngoscope 1980;7:1148-54. 4. Ellner KN, Goldberg LM, Sperber J. Comparison of cosmesis following healing by surgical closure and secondintention. J Dermatol Surg OncoI1987;13:1016-20. 5. AlbrightSD III. Placement of guidingsuturesto counteract undesirable retraction of tissues in and around functionally and cosmetically important structures.J Dermatol Surg Oncol [98 [;7:446-9. 6. Johnson TM, Ratner D, NelsonBR. Softtissuereconstruction with skin grafting. J AM ACAD DERMATOL 1992; 27:151-65. 7. Skouge JW. Skin grafting. New York: Churchill Livingstone, [99[:48-9. 8. Zitelli JA. Burow'sgrafts. J AM ACAD DERMATOL [987; 17:271-9. 9. Robinson JK. Improvement of the appearance of fullthickness skin grafts with dermabrasion. Arch Dermatol 1987;123: 1340~5. 10. SalascheSJ. Acute surgical complications: cause, prevention,andtreatment.J AM ACADDERMATOL 1986;15:116385. 11. SalascheSJ, Grabski WJ. Complications of flaps. J Dermatol Surg OncoI199[;17:132-40. 12. Goldminz D, Bennett RG. Cigarette smoking and flap and full-thickness graft necrosis. Arch Dermatol 199[;127: 1012-5. 13. Braun M III. Being certain the tumor is out. J Derrnatol Surg Oncol 1987;13:1058-60. 14. Rapini RP. Comparison of methods for checking surgical margins. J AM ACAD DERMATOL 1990;23:288-94. 15. SalascheSJ, Winton GB. Cutaneous surgical flaps: basic terminology and concepts. J Assoc Mil Dermatol 1988; 14:19-23. 16. SalascheSJ, Bernstein G, Senkarik M. Surgical anatomy of the skin. Norwalk: Appleton & Lange, 1988:14-23. 17. WebsterRC, Smith RC. Cosmeticprinciples insurgeryon the face. J Dermatol Surg Oneol 1978;4:397-402. 18. Tromovitch TA,Stegman SJ , Glogau RG. Flapsand grafts in dermatologic surgery. Chicago: Year Book, 1989:1-5. 19. Dzubow LM. Flap dynamics. J Dermatol Surg Oncol [991;17:116-30. 20. McGregor LA. Fundamental techniques of plasticsurgery and their surgical applications. Edinburgh: Churchill-Livingstone, 1989:85. 21. Dzubow LM. The dynamics of flap movement: effect of

Summers and Siegle 681 pivotal restraint on flap rotation and transposition. J Dermatol Surg OncoI1987;13:1348-53. 22. Webster RC, Davidson TM . The thirty degree transposition flap. Laryngoscope 1978;88:85-94. 23. Lister GD,GibsonT. Closure of rhomboidskin defects: the flaps of Limberg and Dufourmentel. Br J Plast Surg [972;25:300-14. 24. Salasche SJ, Bernstein G, Senkarik M. Surgical anatomy of the skin. Norwalk: Appleton & Lange, [988:37-44. 25. Salasche SJ, Jarchow R, Feldman SD, et al. The suspension suture. J Dermatol Surg Oneol 1987;13:973-8. 26. SalascheSJ, Bernstein G, Senkarik M. Surgical anatomy of the skin. Norwalk: Appleton & Lange, 1988:43. 27. Bennett RG. Fundamentals of cutaneous surgery.St Louis: CV Mosby, 1988:361-4. 28. Langer K. On the anatomy and cleavabilityof the skin. 1. The cleavability of the cutis. (transl. by T. Gibson) Br J Plast Surg 1978;31:3-8. (Translationfrom a presentationof [861.) 29. Langer K. On the anatomy and physiology of the skin. II. Skin tension. (transl, by T. Gibson) Br J Plast Surg 1978;31:93-106. (Translationfrom a presentationof 1861.) 30. Cox HT. The cleavage lines of the skin. Br J Surg 1941 ;29:234-40. 31. Rubin LR. Langer's lines and facial scars. Plast Reconstr Surg 1948;3:147-55. 32. BennettRG. Fundamentalsof cutaneous surgery.St Louis: CV Mosby, 1988:362-3. 33. Bulacio-NunezAW. A new theory regarding the lines of skin tension. Plast Reconstr Surg [974;53:663-9. 34. Borges AF, Alexander JE. Relaxed skin tension lines, Z-plasties on scars, and fusiform excision of lesions. Br J PlastSurg 1962;15:242-54. 35. BorgesAF. Relaxed skin tensionlines (RSTL) versus other skin lines. Plast Reconstr Surg 1984;73:144-50. 36. Borges AF. Relaxed skin tension lines. Dermatol Clio 1989;7:169-77. 37. Pierard GE, Lapiere Clvl. M icroanatomy of the dermis in relation torelaxedskin tensionlinesand Langer's lines. Am J DermatopathoI1987;9:219-24. 38. Zitelli JA. Tips for wound closure: pearls for minimizing dog ears and applications of periosteal sutures. Derrnatol Clin 1989;7: [23-8. 39. Zitelli JA, Moy RL. Buried vertical mattress suture. J Dermatol Surg OncoI1989;15:17-9. 40. Moy RL, Lee A, Zalka A. Commonly used suturing techniquesin skin surgery. Am J Fam Praet 1991;44-:1625-34. 41. Zachary CB. Basic cutaneous surgery: a primer in technique. New York: Churchill-Livingstone, 1991:69-71. 42. Katz BE, Oca MAGS. A controlledstudy of the effectiveness of spot dermabrasion ('scarabrasion') on the appearance of surgical scars. J AM ACAD DERMATOL 1991;24: 462-6. 43. Yarborough JM. Ablation of facial scars by programmed dermabrasion. J Dermatol Surg Oncol 1988;14:292-4. 44. Tardy ME Jr, Denneny J. Surgical alternatives in scar camouflage. Facial Plast Surg 1984;1:209-25. 45. Davis WE, Renner GJ . Z-plasty and scar revision. In: Thomas JR, Holt GR, eds. Facial scars: incision, revision, and camouflage. St Louis: CV Mosby, [989:[37-49. 46. Webster RC, Davidson TM, Smith RC. Broken line scar revision . CUn Plast Surg 1977;4:263-74. 47. Dzubow LM. Defect subdivision as a technique to repair defects following Mohs surgery. J Dermatol Surg Oncol 1990; 16:526-30.

48. DzubowLM, Zack L. The principle of cosmeticjunctions as applied to reconstruction of defects following Mohs surgery. J DermatolOncol [990;16:353-5.