Melolabial Nasolabial

Description

The melolabial (nasolabial) flap is a random-pattern local flap based either superiorly or inferiorly along the melolabial sulcus and cheek-nasal sidewall. The type of tissue movement is lifting either by transposition into the defect or by interpolation. If the intervening skin between the melolabial sulcus and the defect remains intact, then a staged interpolation flap may be necessary. The flap is harvested preserving the subdermal plexus distally and is based on a skin-subcutaneous pedicle; the flap may also be created as an island based only on a subcutaneous island in selected circumstances (i.e., a subcutaneous island melolabial flap).

Trapdoor Deformity

The length-to-width ratio can be as high as 4:1, although flaps over 10 cm have been used augmented by surgical delay. The width of the flap is limited by the ability to close the donor site primarily (usually < 2.5 cm). Harvesting the melolabial flap begins with an incision along the melolabial sulcus from near the corner of the lip to no more than the distal border of the defect. The width of the flap is the same as the width of the defect, and this measurement determines the lateral incision on the cheek outlining the long axis of the flap. This lateral incision will be open-ended to leave a skin-subcutaneous pedicle positioned inferiorly for inferiorly based flaps and superiorly for superiorly based flaps.

Indications

Superiorly based melolabial flaps are indicated for central, lateral, alar, and nasal tip -g defects, and for defects of the lower eyelid. For more centrally located defects includ- |

ing the nasal tip, interpolation and staging are necessary (Fig. 15). Full-thickness alar »

defects are ideally reconstructed with a superiorly based flap as a one-stage proce- c dure using the twisted melolabial flap (24) (Figs. 16, 17). Partial-thickness defects ^

d may best be reconstructed using an interpolated flap from the lateral cheek (25). >3

Inferiorly based melolabial flaps are indicated for upper and lower lip, floor of |

the nose, columellar, and intraoral defects. Columellar defects may require bilateral o staged interpolation flaps. A partially de-epithelialized flap may be used for single- §

staged reconstruction of the alveolar ridge and anterior floor of mouth. @

Nasal Interpolation Flap

Figure 15 Interpolated nasolabial flap for a partial-thickness defect in the ipsilateral nasal ala. Note in upper right photograph the intermediate stage after initial flap transfer and before final flap division. Lower photograph shows flap inset with shape-retaining suture for the nasal alar flare.

Figure 15 Interpolated nasolabial flap for a partial-thickness defect in the ipsilateral nasal ala. Note in upper right photograph the intermediate stage after initial flap transfer and before final flap division. Lower photograph shows flap inset with shape-retaining suture for the nasal alar flare.

Advantages

The incisions for flap harvest can be hidden in the melolabial fold. There is usually a lot of redundant tissue lateral to the melolabial fold that can be recruited to the flap, especially in older patients. The color match to the skin of the nose is usually very good, second only to the midforehead flap. The melolabial flap accepts cartilage grafts well.

Melolabial FlapMelolabial Fold

Disadvantages

Blunting and asymmetry of the melolabial fold may require surgical revision. Dissecting below the level of the mimetic musculature will place the medial branches of the facial nerve (especially the buccal branches) at risk. Superiorly based flaps are subject to trapdoor and pincushioning deformities because the scar is oriented in a curvilinear fashion near the nasal sidewall. Blunting of the nasofacial sulcus is common, requiring secondary defatting procedures. Inferiorly based melolabial flaps are also subject to trapdoor deformities of the upper lip.

Midforehead Flap |

Description |>

Midforehead flaps are staged local axial musculocutaneous flaps with a variable dis-

d tal random-pattern component. Types of midforehead flaps include the precise mid- >3

line forehead flap, the paramedian forehead flap, and the oblique forehead flap

(Fig. 18). The precise midline forehead flap is centered vertically in the forehead o and its base is between the eyebrows, encompassing both supratrochlear and angular arteries. The paramedian forehead flap is just off the midline and its base is over

Figure 17 Upper photograph shows final stage of insetting a twisted nasolabial flap for a complete nasal alar defect. Lower photograph shows patient 1 week postoperatively.

the medial eyebrow, over the ipsilateral supratrochlear artery, and extending vertically to the hairline. The oblique flap is a paramedian flap that extends across the mid-line of the forehead and along the hairline for additional flap length. Modern refinements to the precise midline forehead flap include its being based on only one supratrochlear artery, allowing the pedicle more freedom to achieve greater flap length.

Oblique Forehead Flap
Figure 18 Penned outline of a paramedian (A) and oblique forhead flap (B).

The midforehead flap is transferred in stages. The first stage involves interpolation of the flap to the donor site leaving the pedicle exposed over the intervening tissues (Fig. 19). The second stage involves pedicle division with local anesthesia 2-3 weeks later. Pedicle division can be delayed to a third stage if intermediate aggressive thinning and sculpture are required at the second stage. After the pedicle is divided; the remainder of the unused flap should be trimmed and replaced into the forehead as an inverted V no higher than the level of the arch of the eyebrows; replacing the entire unused flap with extension above this level gives a less aesthetic result.

The design of the flap should be an exact match to the recipient site defect because forehead skin will not contract. The distal portion of the flap can be thinned to the subdermal plexus (2-3 mm thick), while the proximal part of the flap should include the periosteum (and frontalis muscle) to protect the axial vessels against injury while freeing the flap near its base. Missing cartilage framework should be replaced with grafts from the ear or septum at the time of flap placement in reconstruction of nasal defects. Local septal flaps, such as the septal hinge flap based on | the anterior ethmoidal vessels, are useful to provide inner nasal lining (25). Inner » nasal lining can also be furnished by enfolding the flap and this usually provides good alar and columellar contour if the flap can be sufficiently thinned distally.

Middle vault through-and-through defects are best lined with adjacent skin turnover and septal flaps, appropriate cartilage grafts, and forehead skin for coverage (26). |

The vertically oriented wound at the donor site is closed, primarily facilitated by extensive undermining in the subgaleal plane. Flaps required for the more extensive nasal defects may leave a donor site that will not close primarily near

Supraorbital Ridge Growth
Figure 19 Harvested and transferred paramedian forehead flap in patient A shown in Fig. 18. This is the initial transfer. After 2-3 weeks the flap is divided at the glabella.

the hairline. These wounds can be left open to contract over several weeks, resulting in a very acceptable cosmetic result.

The main vascular supply to this axial flap is the supratrochlear artery; secondary arterial sources include the angular and supraorbital arteries (27).

Indications

Midforehead flaps are used for nasal reconstruction; expanded flaps may reach the lip or cheek but they are rarely used for reconstruction of these areas. The midfore-head flap is best reserved for defects of the nose over 2.5 cm in length (28) (Fig. 20).

Advantages

Forehead skin is nearly identical in color and texture to nasal skin. The distal 2 cm of the flap can be aggressively thinned to match the thickness of the skin in the lower nose. Less aggressive thinning is required in smokers to avoid distal flap necrosis. g

Disadvantages |>

The main disadvantage to the midforehead flap is the vertical scar on the forehead.

Primary closure is not always possible, leaving an area, usually near the hairline, to >3

heal by secondary intention. The length of the flap is limited somewhat by the hairline, although this can be circumvented to a limited extent by using the oblique mid-forehead flap, tissue expansion, or extension into the hair-bearing scalp. If the distal §

flap is overly thinned, distal necrosis is ensured, especially in smokers.

Island-Pedicled Musculocutaneous Nasolabial

Description

The island-pedicled musculocutaneous nasolabial flap incorporates the underlying mimetic musculature at the base (29) (Fig. 21). The flap can then be formed into

Subdermal Plexus
Figure 20 Patient in upper photographs with a deformity of his nasal tip created after cancer was excised and a skin graft applied 15 years earlier. An oblique forehead flap was used to resurface the defect after the skin graft was removed. The result is seen in the lower photographs.
Marking For Nasolabial Flap

an island based on muscular perforating vessels. This island of nasolabial tissue is much more mobile than traditional subcutaneous-based nasolabial flaps and can be transposed to donor sites up to 5 cm away, thus extending the indications of the nasolabial flap to include the total restoration of midline nasal and septal defects (30).

Perforating vessels (terminal arteries) penetrate the overlying levator labii superioris and nasalis muscles to supply the flap. The location of the donor vessels is adjacent to the piriform aperture, and consists of distal branches of the facial artery distal between the labial and alar arteries and more variable superficial facial veins. After penetrating the muscles, these vessels continue in the subdermal plexus. Mobilization of the flap is accomplished through dissection in the nasolabial fold and freeing of the facial artery and vein (Fig. 22).

Indications

The island-pedicled musculocutaneous nasolabial flap is descri bed for total colu-

mellar and caudal septal-columellar defects (Fig. 23). |

Advantages |>

There is minimal donor site distortion and blunting of the alar-cheek junction ^

d because the flap is transferred as an island; staging and secondary revisions are mini- >3

mized. Despite inclusion of muscle at the base of the flap, the vast majority of the |

tissue is elevated in a much more superficial plane based on the subdermal plexus, resulting in thin and pliable flap tissue. Cartilage grafting for nasal support is well §

tolerated.

Angular Artery Necrosis
Figure 22 Nasolabial island flap nourished by angular artery and vein.

Disadvantages

Closure of the donor site as a V-Y advancement can result in a noticeable dual scar in the melolabial crease. Injury to the buccal branches of the facial nerve is a potential complication; however, this has not occurred in reported series (29).

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Responses

  • vicente
    Where is your melolabial fold?
    9 months ago

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