The nose occupies a central position both anatomically and aesthetically in determining the overall appearance of the face. Surgery for reconstruction of the nose has a long history, dating back at least to 2000 bc . In India, nasal reconstruction has been performed by specialized castes for millennia. This grew out of necessity as a common punishment for adulterers, thieves, and prisoners was amputation of the tip of the nose to permanently disfigure the offender. Around 600 bc , Sushruta published Sushruta Samihta , a detailed text reviewing cheek flaps for reconstruction of the nose. Accounts of the midline forehead flap had been noted since at least 1440 ad by a caste of potters in India known as the Koomas. In 1597, Tagliacozzi published a staged nasal reconstruction using skin from the forearm, the first report in the West. The origins of facial plastic surgery can be found in these early attempts by surgeons to recreate a structure that defines aesthetic appearance.
Centuries of refinement and experience have led to current techniques of nasal reconstruction. Defining the normal appearance and appropriate function of the nose has changed only slightly with passing time and cultural preferences. The importance of understanding the characteristics that create the subtle interplay of light and shadows that are perceived as a nose cannot be understated. Only by understanding the anatomy and topography of the structure to be reconstructed can a comprehensive plan for surgery be created. Once a common groundwork of anatomy and physiometry has been established, the surgeon can begin to explore the art and science of this challenging surgery.
When approaching a nasal defect, a systematic method of analyzing the reconstructive options is crucial. Consideration of the location, size, orientation, and depth of the defect are all important. In evaluating the location of the defect, we find it helpful to divide the nose into thirds—upper third, middle third, and lower third, each of which has its own specific reconstructive nuances and pitfalls. The size and orientation of the defect also need to be thoughtfully analyzed when deciding upon a reconstructive option. The immobile structures surrounding the defect (i.e., hairline, eyelid, melolabial fold, among others) need to be considered. Larger defects may require recruitment of tissue from surrounding areas so as not to cause distortion of adjacent features. Also, the orientation of the defect may allow scars to lie within favorable areas maximally camouflaging resulting scars. Next, the depth of the lesion will determine the extent of repair required. The nose can be broken down to three layers for repair: the skin covering, cartilaginous support, and mucosal lining. All layers that are affected need to be reconstructed. Repairing one or two layers in a full-thickness defect without addressing the remaining layers will result in postoperative scarring and a poor aesthetic outcome as the nose becomes distorted under the cicatricial healing forces of the underlying scar. Finally, the subunits involved should be identified. While this may seem trivial, in wounds that have been allowed to heal by secondary intention, the true magnitude of the defect may be obscured until the initial scar tissue has been excised, allowing a complete, aesthetic repair to be performed. Together, these factors will determine the type of repair used.
There are multiple techniques that are possible for the repair of a given defect, each with their advantages and disadvantages. We will limit our discussion to methods that are commonly used in our practice that have provided acceptable and consistent results—the “workhorse” techniques.
The basic anatomy of the nose is important to review prior to discussion of surgical techniques. The subunit principle consists of the observation that shadows naturally fall at the junction of the concavities and convexities of the nose. These surface contours divide the nose into nine distinct aesthetic subunits—nasal tip, paired soft tissue triangles, both ala, nasal dorsum, the two lateral nasal walls, and the columella ( Figure 36-1 ). Scars that fall at the junction of the aesthetic subunits tend to be better camouflaged as opposed to scars that cross a subunit. Lesions involving greater than 50% of a subunit are often best repaired with complete excision and reconstruction of the entire subunit. Lesions or defects involving less than 50% of such subunit are often able to be closed without further sacrifice of surrounding unaffected tissue. When the nose and the entire face are viewed in this manner, the surgeon is able to plan the nasal reconstruction by breaking down even a very large defect according to the subunits it encompasses and formulate a plan for repair by approaching each affected subunit as an individual entity. This principle applies mostly to subunits that are convex such as the nasal tip, alae, dorsum, and columella. This concept is critical due to the natural tendency of skin flaps to contract into convex circular mounds of tissue if unopposed by a structural framework to support it. Skin grafts that are supported by a framework of bone or cartilage will resist this contracture and largely keep their form, making them ideal in reconstructing concave areas such as the nasal sidewalls.
The quality of the skin to be repaired is very important in nasal reconstruction. The upper third of the nose, consisting of the nasal dorsum and lateral walls, has a thicker skin with more laxity. The middle third skin is thin and elastic. Skin grafts and local flaps do well in reconstructing this region. The lower third, consisting of the nasal tip, alae, soft tissue triangles, and columella, has thicker, sebaceous, less pliable skin, which poorly matches most skin grafts. The thick, stiff nature of the skin can make local flaps less reliable and may necessitate the use of pedicled flaps, as we will discuss later. The skin of the dorsal nose tapers to the rhinion, where it is the thinnest. In patients with large defects, the opposite side may be used to estimate the quality of the skin to be repaired.
Underlying the skin is loose areolar tissue followed by the musculature of the nose. These are connected by an aponeurotic system of fibrous tissue that is contiguous with the superficial muscular aponeurotic system (SMAS).
The framework of the nose consists of paired quadrangular nasal bones, upper lateral cartilages, lower lateral cartilages, and the septum. The septum acts as the support for the nose from which the upper and lower lateral cartilages are suspended. An in-depth understanding of the shape, position, and strength of the lower lateral cartilage will prove invaluable in reconstruction of defects involving the nasal alae and tip. Even areas that are not covered by cartilage, such as the soft tissue triangles, must be reconstructed with a supporting framework or risk contraction of the overlying flap or graft.
In evaluating the mucosal lining of the nose, the skin of the vestibule is made up of stratified squamous epithelium. This transitions to the typical pseudostratified ciliated columnar epithelium of the inner lining of the nose just beyond the vibrissae of the vestibule. The thickness of the lining is important to note as reconstruction with thick flaps may lead to obstruction of the external nasal valve. Additionally, use of thinner skin grafts in areas normally covered by mucosa can lead to significant crusting and ozena. Finally, placing mucosa in areas normally covered by stratified squamous epithelium will lead to easy bleeding and irritation due to its proximity to the outside environment and desiccation.
Repair of Surface Defects
Repair of superficial cutaneous nasal defects should be based on the size, color, texture, and curvature of the area to be repaired. While many options exist for a given defect, we will approach this issue by dividing the nose into upper two thirds and lower third to simplify the surgical options available. Overall, the goal of surgical reconstruction of unilateral defects should be to replace tissues with those similar in texture and color. The subunit principle should be applied whenever possible. When planning for closure of defects, scars should ideally come to rest in the areas between subunits.
Nasal Defects of the Upper Two Thirds of the Nose
The upper two thirds of the nose consists of the nasal dorsum and lateral nasal walls extending from the glabella to the caudal aspect of the nasal bone. The skin tends to be relatively thin, less sebaceous, and more mobile compared to the lower third of the nose. This region is supported by the nasal bones and the upper lateral cartilages. For very small cutaneous lesions primarily over the nasal bones, closure by secondary intention remains an excellent option. Primary closure is possible in this region due to the relative mobility of the soft tissue envelope. Scars that are placed along the relaxed skin tension lines (RSTL) and at the junction of aesthetic subunits tend to camouflage best.
Larger lesions in this region can be reconstructed with full-thickness skin grafts ( Figure 36-2 ). This is ideal for the lateral nasal side walls, which has relatively thin, shiny skin and falls within the natural shadows of the nose. Grafts are most commonly harvested from the preauricular region due to the excellent color and texture match. When additional skin is required, skin from the supraclavicular fossa, nasolabial fold, neck, upper eyelid, or postauricular region can be used ( Figure 36-3 ). A template of the defect is created using the foil from a suture packet, which bends easily to fit the contours of the nose. This is transposed to the proposed donor site. As with all skin grafts, a healthy vascularized wound bed is necessary for graft survival. If the periosteum or perichondrium has been removed with the lesion, a vascularized bed must be in place for successful uptake. Of note, the skin grafts must be supported with either a bony or cartilaginous framework. Without this, the graft will shrink due to contraction of myofibroblasts. During the healing process, the surrounding recipient skin can supply the full-thickness skin graft up to 3 ml away by nutrient and oxygen diffusion. Once the graft is harvested, the surgeon thins the graft by removing the subcutaneous fat until the white portion of the dermis is visible. This increases the likelihood of vascularization and subsequent graft viability. It is worth noting that overaggressive thinning of the graft can lead to loss of the dermal layer, leaving the patient with a split-thickness skin graft and the potential for postoperative contracture with irregularity of color and texture. The graft is then placed into the defect and any excess skin is gently trimmed. When trimming the edges of the skin graft, we find it helpful to first trim one side of the graft to fit, which is then sutured into place. The second side is then trimmed and inset and so on until the remaining three sides are subsequently cut to fit the defect. Basting sutures are applied between the graft and the vascularized bed with fast absorbing gut suture to prevent seroma or hematoma formation ( Figure 36-4 ). Central basting sutures prevent the graft from lifting off the bed, while peripheral sutures keep the graft aligned in proper position. Those sutures that remain at the first postoperative visit at 5 to 7 days are then removed.
When possible, we try to use local flaps because of the advantage of similar skin color, thickness, and contours as the missing tissue. In the upper two thirds of the nose, transposition flaps such as the bilobed and rhomboid flap may be used with excellent results.
Bilobed flaps are the most commonly used flaps for repair of smaller nasal defects (<1.5 cm) in our practice, our “workhorse” flap ( Figure 36-5 ). They are based on a random blood supply. The initial bilobed flap as described by Esser uses two equal flaps with a 90- and 180-degree rotation. The amount of rotation and large flaps led to excessive tension on the surround tissues, buckling around the pivot point, and distal distortion. Multiple modifications have been made on the original design with improved outcomes. We often follow the modifications described by Zitelli in our flap design. The angle of rotation has been decreased to less than 50 degrees per flap, or less than 100 degrees for the arc of the entire flap. In general, for the upper two thirds of the nose, a laterally based flap works best. This allows for the majority of the scars to lie within the shadowed lateral nasal wall and can allow for the two relatively linear incisions to lie within junctions of aesthetic subunits.
The initial step in designing the flap is to determine the point of rotation, or the pivot point. This point must be situated sufficiently away from critical adjacent structures such as the lower eyelid, which may cause distortion when the flap is transposed. The pivot point is approximately one radius of the defect away from the edge of a circular lesion. From the pivot point, a Burow’s triangle is marked to account for the standing cone deformity that will occur from the rotation of the flaps. The closure of this limb of the flap will create the first linear scar. We, therefore, attempt to place one side of the Burow’s triangle at the junction of aesthetic subunits when possible, such as at the supra-alar crease.
Once the pivot point is determined and the Burow’s triangle is marked, we then mark out two arcs: one from the pivot point to the most distal edge of the defect and one from the pivot point to the midpoint of the defect. We use a piece of foil to measure the arc of rotation rather than a straight ruler as the curvature of the nose can add significant extra length to the pivot point. It is between these arcs that our lobes will be marked. The first flap is drawn the same size as the defect. Again, the foil from a suture packet can be used to make a template of the original defect for creation of the primary lobe to ensure adequate size. The second lobe is marked approximately 20% smaller than the original defect to ease in closure. A Burow’s triangle is extended from the second lobe to account for the eventual standing cone deformity. The angle between the defect and the secondary flap can be adjusted between 90 degrees and no more than 100 degrees to allow for the closure of the secondary defect to lie at the junction of aesthetic subunits.
Once the markings are complete, wide undermining in the sub-SMAS plane ensues prior to making any releasing incisions. The advantage to undermining in this plane is that it is relatively avascular, the blood supply to the flaps is preserved, and there is less postoperative “pincushioning” of the circular flaps compared to a subcutaneous dissection. Once widely undermined, the flaps are released along the markings, keeping the incisions between the two arcs. The flaps are gently rotated into position and the tension on the flap is assessed. If there is too much tension, the releasing incision along the second lobe is lengthened beyond the lower arc, taking care not to narrow the base of the flap excessively. The incisions are then meticulously closed in layers. This flap is generally limited to defects no larger than 1.5 cm in diameter, as larger flaps will tend to distort surrounding structures when closing the primary and the resulting secondary defects.
In the superior nasal dorsal region, a transposition flap from the glabella works well to repair cutaneous defects. This region has abundant loose skin in comparison to the nasal dorsum and often a unilobed flap such as a banner or rhomboid flap can be used ( Figure 36-6 ). Scars may be oriented vertically to hide in existing glabellar rhytids in the region. Here, undermining is performed in the subcutaneous plane, taking care to avoid injury to the supratrochlear and supraorbital neurovascular bundles.