Perioral Reconstruction

Published on 09/03/2015 by admin

Filed under Dermatology

Last modified 09/03/2015

Print this page

This article have been viewed 7811 times

Chapter 16 Perioral Reconstruction

James T. Chapman, J Ramsey Mellette, Jr.

INTRODUCTION

The lip is the center for both spoken and expressive communication and is one of the most complex cosmetic units of the face. There is a unique interplay of texture, color, and contour at this site. Consequently, there is significant variability from person to person and this variability allows for innumerable reconstructive closures. Surgical management of lip defects has a long history of innovation born out of the difficulties inherent in the reconstruction of this facial unit.

The lips have no underlying bony or cartilaginous attachments, leaving them quite pliable. This elasticity allows for the broad movements required for verbal and nonverbal communication.¹ Perioral reconstructive goals include maintaining oral competency, oral access, and mobility while providing an excellent aesthetic outcome. Maintaining function takes highest priority.²

In this chapter a regional approach to reconstruction of lip defects, primarily partial thickness, will be presented. When planning reconstruction of the lip, designing techniques based on aesthetic subunits will enhance the cosmetic result.³ Closures will vary, depending upon location, size, shape, and depth of the defect. Reconstruction in the perioral region is often challenging and to obtain optimal results requires a profound knowledge of perioral anatomy, including cosmetic subunits, vascular supply, innervation, musculature, and surrounding tissue availability.¹ Finally, general principals and regional pearls for improving cosmetic outcome will be discussed.

Cosmetic Subunits

There are five cosmetic subunits delineating the perioral region into important boundaries and landmarks (Figure 16.1).⁴ When designing closures, these subunits should be respected, whether the closures are simple or need the use of extensive tissue movement. It is understood that in large defects or those that overlap subunits, strict adherence to this principal is not always possible.

Figure 16.1 Perioral cosmetic subunits.

The upper lip is divided into three cosmetic subunits, viz, the philtrum and the right and left cutaneous upper lip. The alar creases, the alar sill, and columella border the upper lip superiorly. Laterally, the borders are delineated by the melolabial folds extending inferolaterally to the oral commissures. The philtrum comprises the philtral crests or columns laterally and the sulcus medially (Figure 16.1). Great care should be undertaken to maintain the philtrum at the midline. The inferior portion of the philtrum forms Cupid’s bow (Figure 16.1). With age the philtrum becomes less prominent.

The vermilion constitutes the fourth subunit and borders the cutaneous upper and lower lips forming the rolled border. The wet–dry line of the vermilion separates the dry cutaneous portion with the inner wet mucosal tissue. As will be discussed, maintaining alignment of the vermilion during lip closures cannot be overstressed.

The cutaneous lower lip is bordered laterally by the inferior portion of the melolabial folds, superiorly by the vermilion and inferiorly by labiomental crease. This constitutes the fifth subunit.

Relaxed Skin Tension Lines

Relaxed skin tension lines are created by the intricate pull of the orbicularis muscle and the surrounding facial musculature. They extend in a radial direction from the oral aperture usually perpendicular to the rolled border.

During reconstruction on defects of the lips, regard should be utilized to close defects within the relaxed skin tension lines whenever possible. Often pronounced in smokers and those with severe sun damage, these exaggerated lines offer surgeons clear options for closure. This is not the case in young undamaged skin, or in skin of the lower cutaneous lip. Care should be taken to manipulate the skin, looking for favorable lines of closure. Closures along relaxed skin tension lines will heal under less tension and be much better camouflaged than those placed against them.

Perioral Musculature

The movements necessary to convey emotional expressions and maintain functional competence is accomplished by the machinations of multiple muscle groups.

The sphincter-type orbicularis oris muscle runs circumferentially, providing the main bulk of the lip and acts in concert with surrounding facial musculature. The lip elevators lift the angles of the mouth superiorly and constitute much of the melolabial fold. They also form the philtral crests, and oral commissures. The lip depressors provide inferior movement of the angles of the mouth. When significant muscle is lost or when defects are quite large, plicating sutures may be necessary.

Sensory Innervation

Sensory innervation to the perioral region is relatively straightforward. Innervation is supplied by branches of the trigeminal nerve (cranial nerve V). The infraorbital branch supplies sensation to the upper lip and the mental branch to the lower lip (Figure 16.2). Identification of the mental and infraorbital foramina aids the surgeon in providing significant anesthesia for larger lip defects. The foramina can be reached either percutaneously or via an intraoral route. Further discussion of anesthetics and regional blocks appears in the “General Principals” section.

Figure 16.2 Sensory innervation to the lip.

Motor Innervation

The orbicularis oris and lip elevators receive motor inner-vation from the buccal branch of the facial (VII) nerve. The marginal mandibular branch innervates the lip depressors. Unless there is extensive muscle tissue loss, damage to these nerves is unlikely, as they lie deep to the orbicularis oris and perioral musculature. If damaged, the marginal mandibular nerve may lead to significant functional and cosmetic deformity, including the inability to pull the lower lip laterally and downward. Eversion of the vermilion may also be compromised.⁵

Vascular Supply

The arterial supply is derived from the superior and inferior labial arteries arising from each facial artery located just lateral to the oral commissures (Figure 16.3). The labial arteries course medially beneath the orbicularis oris muscle in the submucosa. Smaller branches of the labial arteries ascend and descend to supply the cutaneous portions of the upper and lower lips. The superior labial branches also supply the ala and columella.

Figure 16.3 Arterial supply to the lip.

GENERAL PRINCIPALS OF LIP RECONSTRUCTION

There are few absolutes in perioral reconstruction. Every patient has distinctive features that offer multiple reconstructive options. A specific closure used in an elderly patient may be less advantageous in a younger patient. Young people, or those with minimally damaged skin, have greater tissue volume and less tissue laxity. Even small defects in these patients may represent a significant challenge. Elderly skin, being more forgiving, allows the surgeon the capacity to close larger defects with often-superior results.

There are a few fundamental principals that will benefit all reconstructive surgeons and improve cosmetic results. Prior to executing any perioral reconstruction, all aesthetic subunits and favorable lines of closure should be properly marked with indelible ink before anesthetic infiltration. The use of regional nerve blocks decreases the need for local anesthesia, resulting in less distortion of important closure lines. Regional anesthesia of the upper and lower lips is best achieved via the intraoral approach. The infraorbital nerve block is accomplished by inserting the needle into the superior labial sulcus directly over the canine, angling upward toward the infraorbital foramen. The needle is advanced approximately 1 cm toward the foramen and 0.5 to 1.5 cc of anesthetic is injected. A mental nerve block is achieved by inserting the needle into the inferior labial sulcus between the first and second premolars. The needle is advanced several millimeters and 0.5 to 1.0 cc of anesthesia injected. The authors also advocate the use of small amounts of bupivacaine injected into the Mohs defect after each stage. This lengthens anesthesia and reduces the amount of lidocaine used during each stage, and also results in less distortion.

When planning reconstruction of the lips, one should pay particular attention to favorable lines of closure. Cosmetic outcome is greatly improved when incisions are placed within relaxed skin tension lines or at the borders of cosmetic subunits. The most important cosmetic unit is the vermilion– cutaneous junction. Even slight misalignment of this border during reconstruction produces disconcerting results. As previously mentioned, careful marking of the vermilion border will prevent unwanted outcomes.

Often the key to successful reconstruction is adequate undermining. Undermining of the lip occurs just above the muscle layer. When performing large advancement or transposition flaps, extensive undermining in the cheek provides adequate tissue movement and minimal tension on the wound closure. A sequela of undermining in this highly vascular region is the potential for measurable bleeding. Meticulous hemostasis is required before closing any wound on the lip. Further recommendations for improving surgical technique and cosmetic outcome are detailed in Table 16.1.

TABLE 16.1 SURGICAL PEARLS FOR THE PERIORAL REGION

Delineate the vermilion border prior to infiltration of anesthetic.

Carefully realign the vermilion border during reconstruction to prevent notching.

Perform meticulous hemostasis on all perioral closures.

Advancement flaps should be laterally based to avoid flattening of the philtrum.

Minimize tension on upper lip advancement flaps by utilizing a lateral releasing incision.

When performing Cupid’s bow repairs outline the philtral crests and make certain the center of the bow is exaggerated inferiorly toward the tubercle to avoid subsequent blunting of the bow.

Utilize periosteal sutures to recreate the melolabial fold.

Widely undermine the cheek to increase tissue movement in advancement and transposition flaps.

Be gentle with perioral tissue by using skin hooks instead of forceps for tissue dissection and flap movement.

When designing a lower lip mucosal advancement flap, extend the incision line 0.5 to 1.0 cm above the oral commissures onto the upper lip vermilion to avoid resulting troughs at the angles of the mouth.

Dissect below the minor salivary glands when performing a mucosal advancement flap.

Use braided sutures when closing vermilion or cutaneous–vermilion defects.

Utilize vertical mattress suturing technique on all vermilion-to-vermilion closure to prevent a trough-like scar.

Using Telfa as a template in melolabial transposition and interpolation flaps will ensure proper length and width of the flap.

Close all four layers individually in full-thickness defects.

Choosing the optimal closure depends on skin laxity, as well as the size, location, and depth of the defect. Specific subunits are best served by particular closures that disguise scars in the favorable lines of that subunit. Whenever possible, reconstructive efforts should be made to close defects within a single subunit. Algorithms for reconstructive options for both upper and lower lip defects, with further division by subunit, are provided as a guideline (Figures 16.4, 16.5). These represent the variations of most common local flaps utilized in perioral reconstruction and the locations where they are best utilized. Obviously, an individualized approach to reconstruction tailored around multiple factors, including patient characteristics, is desirable in choosing the proper repair.

Figure 16.4 Upper lip reconstruction algorithm.

Figure 16.5 Lower lip reconstruction algorithm.

RECONSTRUCTION

Upper Lip Defects

Philtral Subunit

Reconstruction of the philtrum offers reconstructive surgeons a significant challenge. Creases, found on the lateral upper lip, are often absent in the philtral region. The philtrum is a reservoir of mobile skin utilized in the multitude of oral movements that stretch the upper lip, as in smiling or crying.⁴ The philtrum is formed by compression of dermal collagen combined with decussation of the orbicularis oris muscle fibers, which insert into the contralateral philtral ridge.⁴

Healing by second intention is rarely an option in this location. Scar contraction with increased likelihood of distortion of the philtrum and possible eclabium formation may result with second intention, especially near the vermilion border. Four closures, depending upon the size, depth, and location of the defect, are primarily utilized in the philtral subunit. These include primary fusiform with or without M-plasty, island pedicle flap, full-thickness skin graft, and Cupid’s bow repair. Each closure, with its merits and limitations, will be discussed.

Wounds smaller than half the width of the philtrum may be closed in a side-to-side fashion with generally excellent cosmetic results (Figure 16.6). Larger wounds, closed primarily, have a tendency to risk unnatural flattening of the upper lip.⁶ The use of an M-plasty may be incorporated to shorten the length of the scar and prevent extending the defect onto the vermilion. It is very important to remember that because of the arc of a fusiform closure there is a lengthening of the distance between the superior and inferior ends of the defect. In larger defects closed primarily this lengthening may cause a displacement of the free margin and an unacceptable depression of the lip below the scar.⁶

Figure 16.6 (a) Philtral sulcus defect. (b) M-plasty excised. (c) M-plasty repair sutured. (d) Long-term result.

Island pedicle flaps are ideal for defects involving the sulcus that are too large for primary closure or Cupid’s bow repairs. They are best utilized for defects encompassing less than 50% of the philtral height and up to 1.5 times the width of the philtrum.⁶ Defects involving greater than 50% of the philtral height have a greater chance of developing eclabium. The island pedicle flap is designed as an exaggerated equilateral triangle of tissue superior to the defect (Figure 16.7a). For large defects the triangle may extend onto the columella. The vermilion border should be marked prior to infiltration. Careful incisions are made down to the superficial subcutaneous tissue. Undermining in this plane should proceed laterally at a slight bevel away from the flap, providing a broad-based pedicle. Extensive undermining of the flap down to fascia may be necessary for adequate flap movement. A small portion of the superior and inferior attachments to the myofascia may be severed for increased movement without compromising lateral blood supply. If there is any significant tension created by the tethered pedicle of the flap, it may elevate the mucosal lip and create an unacceptable result. In some instances, it may be necessary to completely free the flap from its base and convert it into a Burow’s graft. Better to make it into a graft than to have any unnatural distortion of the vermilion. Removing normal tissue at the inferior edge of the defect down to the vermilion border may be necessary to hide the scar within the vermilion border and optimize the aesthetic result. The flap is mobilized inferiorly with the key sutures placed between the distal end of the flap and the defect (Figure 16.7b). Few, if any, subcutaneous sutures are placed as they may increase the chances of ischemia and eclabium. The secondary defect is closed easily in a side-to-side fashion. A representative final result is often imperceptible except to the trained eye (Figure 16.7c). When the vermilion lip is involved, a triangular- or rectangular-shaped mucosal advancement flap of the same width should be performed to reduce the chance of abnormally elevating the vermilion.

Figure 16.7 (a) Defect of the philtrum with triangle of tissue drawn. Arrow: direction of movement. (b) Island pedicle sutured into place. (c) Long-term result.

There are several potential disadvantages to an island pedicle flap in this location.

Because of the lack of radial skin lines in the philtral sulcus, resultant oblique suture lines have a tendency to be more noticeable. Dermabrasion, dermal sanding, or laser resurfacing 6–8 weeks after surgery may help minimize obvious suture lines. If pin-cushioning of the flap results, it can be improved with intralesional steroid injections and dermabrasion. The chances of having an upward pull or eclabium of the vermilion can be diminished with adequate flap undermining, freeing any significant areas of tethering, and making sure the defect is less than half the philtral height.

Although uncommon, certain large defects involving the philtrum often preclude the use of a local skin flap (Figure 16.8a). In these cases, a full-thickness skin graft (FTSG) may provide the best cosmetic outcome. It may be beneficial to remove normal tissue to make the defect more symmetrical or (Figure 16.8b) even remove the entire subunit to create a more natural appearance. The FTSG is usually harvested from the pre- or postauricular skin, as these areas can both provide enough tissue for large defects and ensure an adequate tissue match. In smaller defects, a Burow’s full-thickness graft provides a superior color and texture match.³ The FTSG is trimmed of fat and then secured with a variety of suture materials, including 5.0 or 6.0 nonabsorbable polypropylene or fast-absorbing gut (Figure 16.8c). Careful suturing technique reapproximating papillary dermis of the FTSG to papillary dermis of the wound edge improves the likelihood of achieving the best cosmetic result.⁷ A bolster dressing may be used to limit shearing forces on the graft during the initial phase of healing. The liberal use of petrolatum ointment in addition to petrolatum-impregnated gauze helps prevent desiccation of the graft. Sutures are left in place for 7 days.