the Melolabial Flap
Ritchie A.L. Younger
INTRODUCTION
Dieffenbach, in 1830, popularized the melolabial flap for reconstruction of the nose using superiorly based melolabial flaps to rehabilitate the nasal alae. Von Langenbeck, in 1864, used variations of superior and inferior based flaps depending on the orientation, position, area, and thickness of the flap required for the reconstruction of the nose. Esser, in 1921, employed an inferior based melolabial flap to close palatal fistulae.
The melolabial flap is a versatile technique for functional and esthetic rehabilitation of defects of the central portion of the face. Variations of this flap may be used to reconstruct small- to medium-sized defects involving the chin, upper and lower lip, cheek, nose, and lower eyelid. Because of the relative proximity of this donor site to these areas, not only is the color match of the skin excellent but hiding the donor site incision in a natural crease line (that frequently deepens with age) affords excellent camouflage.
The melolabial area extends from the inferior lateral attachment of the nasal alae to the lateral mouth area, in effect comprised of the volume of tissue surrounding the melolabial crease. The inferior aspect of the melolabial area can be hair bearing in males, with generally less hair in females. This hair variation can be used to advantage occasionally, depending upon whether there is a need to bring hair-bearing or hairless skin into a specific defect.
The surgical literature frequently refers to this region as the nasolabial area, but anatomically speaking, the more accurate descriptor would be melolabial, as the region is in fact bounded by the melum laterally and the labium medially. The superficial musculoaponeurotic system (SMAS) has platysmal fiber remnants extending superiorly and medially, interdigitating with the muscular layers of the orbicularis oris at the melolabial area. The age-defining melolabial crease forms as soft tissue volume depletes at this watershed area where the orbicularis and SMAS fibers meld together. We performed 10 bilateral cadaver dissections at the University of British Columbia Department of Anatomy, which clearly revealed that, for safe elevation of a melolabial flap, the depth of dissection is limited by the orbicularis oris muscle medially and the SMAS fibers laterally. Penetrating these muscle groups reveals the superior and inferior labial arteries in the perioral area medially, indicating that safe atraumatic elevation should preserve these vessels and stay superficial to the perioral musculature. Lateral to this, if one goes as deep as the labial vessel plane of dissection, one could potentially injure the terminal branches of the buccal branch of the facial nerve. The vascular supply to the melolabial flap area is based on the facial artery and the random superficial terminal branches, with venous drainage going to the facial vein. The all-important blood supply to the melolabial flap is not actually based on a specific vessel found in the flap, but rather on a directionally oriented subdermal plexus that courses parallel to the melolabial crease, giving the flap a certain degree of axiality. Essentially, it is a random flap with a directional orientation to the blood flow. Sensory innervation is by way of the infraorbital and mentalis branches of the trigeminal nerve, with motor nerve supply to surrounding musculature via the facial nerve.
HISTORY
Patients that might benefit from the use of a melolabial flap typically fall into one of three categories: a direct referral from a Mohs surgeon (59.3%), a lesion of the central face that I personally excised by using frozen sections to verify margins (31.5%) or patients with a functional or esthetic issue of the central face where a melolabial flap could be used to help resolve the issue (9.2%). Relevant history from the patient that might impact the technical aspects of the planned reconstruction include any microvascular comorbidities (smoking, diabetes, or previous radiation to the donor or recipient site), previous surgery or trauma to the donor or recipient site, and finally systemic hematologic problems (common anticoagulant use in the elderly for atrial fibrillation and cardiac vessel stenting) affecting flow, bleeding, or coagulation in the surgical arena. Pre-Mohs surgery photographs can provide useful information for planning the volume, sizing, and projection of infrastructural grafts for nasal recipient sites, and a careful ophthalmic assessment can help to diminish complications secondary to lower eyelid reconstruction.
PHYSICAL EXAMINATION
A careful examination of the patient is undertaken to determine exactly what is necessary to fabricate an anatomically correct component of the face that is not only functionally accurate but also esthetically balanced and will blend with surrounding facial features. One of the prime tenants of esthetic cutaneous facial reconstruction includes matching color, texture, surface area, and volume of a defect. The location of the melolabial flap donor sites easily affords excellent color matching to most central facial recipient sites. Texture, due to the relative similarity of the melolabial flap surface to potential reconstructed sites, is typically not an issue, except when considering the prospect of mismatching hair-bearing and non-hair-bearing regions. Ideally, I like to see non-hair-bearing donor sites when moving a flap into a non-hair-bearing recipient area (nose and eyelid), and sometimes, I can succeed by taking a hair-bearing flap into a hair-bearing recipient area (upper and lower lip). Current technology with hair epilation lasers allows us to sometimes place a hair-bearing flap into a non-hair-bearing area, but ideally, this can be avoided with judicious planning. The size and volume of the defect is studied so that the best option for reconstruction may be chosen, not only to achieve a superb recipient site result but also to ensure that the donor site can be closed to minimize deformity. Since flap design, volume, and size are limited to the redundancy of available anatomy, medial and superior based flaps are limited not only in width (1 to 5 cm, depending on the laxity of the facial skin) but also in length (1 to 12 cm, depending on the vertical height of the face). Conversely, inferior based flaps are more limited in width and length, as available tissue is more horizontally restricted (substantially less in the upper reaches of the melolabial area) and vertically limited by the nose, medial canthus, and lower eyelid. Pedicle orientation is chosen based on the location of the defect and influenced by whether mostly rotation or advancement will be required to close a resulting defect. Flap thickness at the working end of a pedicled melolabial flap should mirror the thickness of the surrounding recipient site, whereas the thickness of the pedicle itself is somewhat more boundless, although limited by the depth afforded by the presence of the SMAS-orbicularis sheath guarding the neurovascular plexus below.
INDICATIONS
Any reconstructive ladder dealing with defects of the face should in theory mention the possibility of allowing either secondary intention controlled granulation closure of the defect or employing some form of skin or composite graft reconstruction. When we are dealing with easily distorted anatomical structures such as the lower eyelid, lower nose or lip, secondary intention or skin grafting typically remains a poor choice for many reasons. Split-thickness skin grafts not only are a poor color and volume match usually but also can contractually distort some of the fragile anatomy of the lip, eyelid, or nose. Full-thickness grafts can frequently disappoint in volume matching the recipient site, and again, color can be a problem. Composite grafts can be used for small defects in younger individuals with no microvascular comorbidities (smoking, diabetes, or radiation), but surface area and volume limitations can restrict common usage of these elegant grafts.
Choosing a flap for facial reconstruction is invariably determined after weighing the options and figuring out what will give you the best possible result at the recipient site with minimal donor site morbidity. Melolabial flap selection follows the elimination of other flap choices and usually is an easier choice if the patient is perhaps more senior with an already present melolabial crease. For moderate-sized non-full-thickness defects of the upper or lower lip, with dimensions more horizontally oriented, the melolabial flap is a good choice. Superficial or full-thickness defects involving the lower two-thirds of the nose (including the columella) requiring skin, volume, and/or infrastructural support can, in theory, be rehabilitated with primary or staged suprabrow, midline or paramedian forehead, or melolabial flaps (Fig. 43.1). Suprabrow flaps are somewhat limiting due to their donor morbidity and limited potential skin area, whereas forehead flaps provide a possibly massive skin area with modest donor site issues. Melolabial flaps lie somewhere between the two, and where there is already a deep melolabial crease with generous tissue laxity, it becomes the flap source of choice. The melolabial flap has arguably less donor site morbidity (vs. forehead flaps) and normally does not need to be
delayed (may be necessary with suprabrow flap), but the melolabial flap blood supply is not quite as robust as the forehead sites and must be elevated as atraumatically as possible.
delayed (may be necessary with suprabrow flap), but the melolabial flap blood supply is not quite as robust as the forehead sites and must be elevated as atraumatically as possible.
 FIGURE 43.1 Superiorly based melolabial interpolated flap for nasal tip, alar, and columellar reconstruction. A: Immediate post-Mohs surgery defect. B: Twenty-four months postoperative image after four stages of surgery with reconstruction of nasal tip, alae, and superior columella. |
For smaller defects (<2 cm diameter) of the inferior aspect of the nose, local nasal flaps such as transposition or bilobe are a notably better and less invasive option. For larger defects involving the alar rim or a full-thickness loss, the melolabial flap will generally provide surface area, adequate bulk, and a vascular supply, which will support a cartilage graft (Fig. 43.2). Defects of the inferior aspect of the nose or the lips (upper or lower), oriented horizontally, can be more readily covered with a melolabial flap than a forehead
flap (Fig. 43.3), while conversely, a vertically oriented nasal defect is better closed with a forehead flap or direct advancement from side to side on the nose (if the nose is rather wide and might require cartilage modifications). Medial cheek, intraoral, and eyelid defects may be reconstructed with a melolabial flap, if other more readily accessible local flaps are not an option. After weighing all of the grafting and flap options, if the melolabial donor site provides the best color match, contour, volume, and functional rehabilitation, with the least donor site morbidity, it remains the best choice.
flap (Fig. 43.3), while conversely, a vertically oriented nasal defect is better closed with a forehead flap or direct advancement from side to side on the nose (if the nose is rather wide and might require cartilage modifications). Medial cheek, intraoral, and eyelid defects may be reconstructed with a melolabial flap, if other more readily accessible local flaps are not an option. After weighing all of the grafting and flap options, if the melolabial donor site provides the best color match, contour, volume, and functional rehabilitation, with the least donor site morbidity, it remains the best choice.
 FIGURE 43.2 Superiorly based melolabial transposition wraparound flap. A: Skin cancer noted at alar rim prior to Mohs surgery. B: Immediate post-Mohs surgery defect. |
 FIGURE 43.2 (Continued) C: Immediate postoperative wraparound transposition flap with ear cartilage graft for alar infrastructure. D: Twelve months postoperative view notable for an absence of a poorly formed supra-alar crease. E: Revision surgery to create a supra-alar crease. F: Immediate postoperative view after creation of a supra-alar crease. |
 FIGURE 43.2 (Continued) G: Eighteen months post-Mohs with wide alar rim. H: Revision surgery planning to thin alar rim. I: Twenty-four months post-Mohs inferior view showing thinned alar rim. J: Twenty-four months postoperative result. |
