Aesthetic nasal reconstruction

6 Aesthetic nasal reconstruction







Historical perspective


The history of facial and nasal reconstruction is the history of plastic surgery.1



Cover


Although cartilage, bone, and mucous membrane are missing in larger defects, skin is the most obvious deficiency. Early surgeons focused on the replacement of external skin.


The origins of forehead rhinoplasty (the Indian method) are obscure.2 Nasal repair was described in the Hindu Book of Revelation, the Samhita Susruta, as early as 400 ad and probably was performed before the birth of Christ. Italian surgeons, Branca and Tagliocozzi, reconstructed the nose with skin from the upper arm in the late 1400s.3,4


The first written English account of an Indian midline forehead rhinoplasty appeared in the Madras Gazette in 1793 and was republished in the Gentleman’s Magazine of London 1 year later. Carpue,5 an English surgeon, published his account of two successful operations in 1816. This classic vertically oriented median forehead flap design was popularized in the US by Kanzanjian6 in 1946. The base of the flap, which harvested midline forehead tissues and twisted 180°, was supplied by paired supratrochlear vessels. Its pedicle base was located above the eyebrows.


These early repairs were unlined. The external shape of the nose and its airways became distorted by the contracting scar on the underlying raw surface of the external flap.7


The importance of lining replacement did not become clear until the period between 1840 and World War I.8 Because residual intranasal mucosa mucous seemed inadequate, Petralli folded the distal end of the flap on to itself for lining around 1842. However, because of the high pivot point of the classic median flap, its length was inadequate to create a long columella, satisfactory projection, or to permit infolding for lining without transferring hair-bearing skin on the distal end of the flap.


To increase flap length distally, Auvert, in 1850, slanted the flap’s design obliquely across the forehead. German surgeons designed forehead flaps horizontally, supplied by the supraorbital vessels on one side. In 1935, Gillies8 described an up-and-down flap which was centered over one supraorbital pedicle, passed into the hair-bearing scalp, and then descended back into the forehead. In 1942, Converse9,10 modified the up-and-down flap by creating a long pedicle based on the lateral blood supply of the scalp to camouflage scars within the hair-bearing skin. Other designs included New’s sickle flap,11 which transferred skin from the temple recess based on the ipsilateral superficial temporal vessels, or Washio’s flap,12 which transferred skin from behind the ear, based on the anastomosis of the postauricular and superficial temporal vessels.


The Converse scalping flap, lined by folding its distal end on to itself or by prelamination, became the most commonly used method during the late 20th century.


Unfortunately, these modifications created a forehead defect that was harder to close.


To avoid the limitations created by the high pivot point of the median forehead flap, other surgeons lengthened its design by modifying incisions at the pedicle’s base. Lisfranc, in 1829, extended one incision lower than the other at the base of the pedicle. Dieffenbach lengthened one incision until it reached the defect. Labat curved his incisions proximally, centering the flap over the medial brow and canthus on one side, creating a unilaterally based vertical flap.


These innovations reduced the twist of the pedicle base and brought the flap closer to the recipient site by lowering its point of rotation. This vertical paramedian flap transferred forehead tissue on a unilateral pedicle blood supply, located near the medial canthus. The anatomic studies of MacCarthy et al.13 and Reece et al.14 demonstrate that the forehead is perfused by an arcade of vessels supplied by the supraorbital, supratrochlear, infraorbital, dorsal nasal, and angular branches of facial artery and on branches of the superficial temporal artery. A rich plexus of vessels, centered on the medial canthus, can reliably perfuse a unilateral flap.


Refinements also developed to minimize potential donor deformity. Velpech, in 1828, designed his flap as a reversed ace of spades, with its stem forming the columella and its tapering tip as the pedicle. Labat, in 1834, designed a similar tripod-shaped flap, with limbs extending obliquely across the forehead. Millard,15 in the 1960s, used a seagull-shaped flap with a central vertical component and lateral wings. The wings extended horizontally, as lateral extensions which resurfaced the ala and flowed into the alar bases and nostril sills. The vertical component covered the dorsum, tip, and columella. Undermining of adjacent wound edges allowed partial closure and a relatively inconspicuous midline T-shaped scar, even in large defects.


Today, the vertical paramedian forehead flap, with a unilateral supratrochlear pedicle, is the first choice for nasal repair because of its vascularity, size, reach, reliability, and relatively minimal morbidity. Importantly, because a unilateral vertical flap does not encroach on the opposite forehead, a second vertical flap can be harvested with relative ease.


In modern times, forehead expansion has been used to increase the available surface area of the forehead or to ease closure and minimize donor deformity when forehead dimension is limited in height or width due to a low hairline or prior forehead scarring.



Lining


As Harold Gillies stated in 1920,8,16,17 “One is struck chiefly with the lack of appreciation of the need for lining membrane for all mucus-lined cavities.” In actual fact, except that the forehead skin most closely resembles nose skin, the origin of cover is the least important.”


For at least 2000 years, surgeons placed a flap over a full-thickness defect but left its raw undersurface to heal secondarily. Unfortunately, the external shape of the nose and the airways became distorted by contracting scar. In the mid 18th century, Petralli folded the distal end of the flap on itself to form, in a manner of speaking, a tip, ala, and columella. Volkman, in 1873, turned down the scar tissue lying adjacent to the defect, as hingeover flaps. Thiersch transferred flaps from other facial areas in 1879.7 Millard,15 in the 20th century, rolled over bilateral nasolabial flaps to line both the alae and columella.


In 1898, Loosen applied a skin graft to the underlying raw surface of the covering flap at flap transfer. However the “take” was inconsistent and late contracture common. Others placed a split- or full-thickness skin graft on the deep surface of the forehead flap during a preliminary operation. Weeks later, once the viability of the graft was assured, the skin-grafted flap was transferred to supply both cover and lining. Gillies,18 in 1943, popularized prelaminating the forehead flap with composite chondrocutaneous grafts. In 1956, Converse19,20 recommended septal mucoperichondrial cartilage grafts. However, these methods of prelamination (formerly referred to as prefabrication) delayed formal repair and created a relatively unsupported and shapeless nose.


Gillies21 developed the skin graft inlay method for the saddle-nose deformity of syphilis and leprosy. If lining and support were lost but the overlying nasal skin remained intact, he released scar on the undersurface of the external skin and applied a skin graft to the underlying raw surface. A permanent internal prosthesis was worn to splint the graft and maintain nasal shape and airway patency.


Burget and Menick,22 realizing that the forehead is composed of skin, subcutaneous fat, and underlying frontalis muscle, tunneled a cartilage graft within a vascularized pocket within the subcutaneous fat of a full-thickness forehead flap. The deep undersurface of the frontalis muscle was skin-grafted for lining. The buried cartilage graft “stented” the skin graft lining, much like Gillies’ external splint.


Burget and Menick23 popularized the use of residual intranasal lining flaps, based on axial vessels, for lateral, heminasal, and near-total nasal defects. Because such intranasal lining flaps were thin and relatively reliable, primary cartilage grafts could be employed simultaneously to build a delicate hard-tissue layer to support and shape the nose during the initial stages of reconstruction.


Menick24,25 modified the traditional folded-flap and lining skin graft approaches. Because the distal end of a folded forehead flap or a lining skin graft heal to the adjacent residual nasal lining within 3–4 weeks, they are no longer dependent on the flap’s pedicle for survival. The distal end of a folded flap (cut free from the proximal flap) or a skin graft (which was initially revascularized from the forehead flap’s deep surface) survives, even when the covering flap is completely re-elevated. This permits the placement of a delayed primary support framework over the newly vascularized lining, prior to pedicle division.


Over the last decade, distant tissue has been transferred for lining, as a free flap. Until recently, the technical elegance of microsurgery has not matched the artistry required to make a normal nose. However, recent advancements by Burget and Walton,26 employing multiple individual forearm skin paddles and a two-stage forehead flap with an intermediate to debulk the mid-vault, and Menick and Salibian’s folded single-paddle radial forearm flap,27 combined with a three-stage forehead flap, have produced good results.




Basic science/disease process


Nasal deformity may follow congenital malformation, trauma (including burns), the sequela of skin cancer treatment by excision or radiation, infection, or immune disease.25 Infection must be controlled, tumor eradicated, and immune disease in remission. Often reconstruction is delayed for weeks to years to allow wound stabilization and maturation and verification of disease control.


Staged excisions with delayed repair are especially advantageous in the more extensive cancer which requires more complex reconstruction. Ideally, the patient is seen prior to tumor excision. The diagnosis is verified, the likely extent of excision and reconstruction discussed, and the treatment options outlined. Preoperative medical clearance can be obtained, if necessary. Operative time is scheduled for the future. Excision is performed and a follow-up appointment made to evaluate the defect after tumor clearance. During the postexcisional consultation, the true extent of the defect is confirmed and anatomic and aesthetic losses are defined. Reconstruction follows within 48–72 hours. Because the extent of the defect has been defined prior to repair, the patient understands the requirements of reconstruction and becomes a cooperative, informed partner.


Such coordinated excision and repair provide an opportunity to think, plan, and discuss options with the patient in a leisurely manner, prior to entering the operating room. A surgical plan is developed preoperatively, decreasing patient and surgeon anxiety and ensuring the best result. Because tumor clearance has been confirmed prior to repair, the length of anesthesia and operative times are shortened. Most importantly, disruption of the operative schedule and intraoperative decision-making are minimized.




Planning an aesthetic nasal reconstruction




The traditional approach


Traditionally,22,25 surgeons sought to “fill the hole” and obtain a healed wound. The defect determined the repair. The design and dimension of a skin graft or flap were determined by the apparent, but often distorted, defect. Scars and additional donor injury were overriding concerns. A comprehensive plan to restore multiple, independent, three-dimensional facial features was rarely envisioned. The emphasis was on tissue transfer (skin graft or flap), blood supply, or the replacement of anatomic layers (cover, lining, support). Without primary support placement, unchecked forces of healing led to contracted scars, pincushioning, and airway collapse.


This traditional approach failed to appreciate the strong motivation of patients to look as they did before. It followed a “less is more” cautious approach with little expectation of restoring the normal.



False principles











The modern approach to nasal reconstruction


Aesthetic results depend upon the surgeon’s and patient’s choices.22,25 The modern approach relies on the visualization of the “normal” and the determination of what is missing, both anatomically and aesthetically.28 This regional unit approach emphasizes the judicious choice and modification of recipient and donor tissues to provide for the exact replacement of facial units. The principles of facial reconstruction have switched from traditional wound perspective (how big, how deep, anatomy, and flap blood supply) to a visual one. A healed wound, tissue survival, or the replacement of anatomic layers are necessary, but not sufficient, to restore a normal appearance and function. The mature surgeon, with training and experience, “sees the future.” He or she conceptualizes what will work among available options, while visualizing the desired result. A plan is formulated, principles outlined, and techniques and methods chosen.


Fortunately, although each defect is different, all repairs are simplified because the “normal” is unchanging. Often, the contralateral normal remains as a visual standard for comparison. If not, the ideal is the guide. The “normal” nose is visually defined by its dimension, volume, position, projection, platform, symmetry, and expected skin quality, border outline, and three-dimensional contour. Major facial landmarks are described as regional units – adjacent topographic areas of characteristic quality, outline, and three-dimensional contour. A unit approach helps the surgeon conceptualize the goal, define the requirements of repair, balance options, and measure the success of the result. Goals, priorities, stages, materials, and method of tissue transfer are clearer with the ideal normal in mind (Fig. 6.1 and Table 6.1).



Table 6.1 Gillies’ and Millard’s “10 commandments” of plastic surgery







(Reproduced from Gillies HD, Millard DR. The principles and art of plastic surgery. Boston: Little Brown, 1957.)


In the latter half of the 20th century, Gonzalez-Ulloa et al.29 divided the face into regions, based on skin thickness. Millard30 envisioned major facial landmarks as “units” and recommended replacing them in their entirety with “like” tissue, of similar color and texture, to avoid a patch-like repair.


Burget and Menick31 divided the nose into “subunits” based on skin quality, border outline, and three-dimensional contour.



The concept of peripheral and central facial units


The face can be divided into areas of characteristic skin quality, border outline, and three-dimensional contour. It can be divided into peripheral and central units. Practically speaking, regional unit concepts provide a rational explanation for clinical observation and treatment recommendations.22,25



Peripheral units


The forehead and cheek are peripheral facial units. Like a “picture frame,” they lie at the periphery of the face and receive secondary intention. Their surfaces are largely flat and expansive and their border outlines variable, according to hairline and eyebrow position. Because their borders are not visible in all views, their borders cannot be compared to the contralateral normal side for symmetry or outline.


So, because the character of peripheral units is less exact and constant, their repair is less demanding and of secondary importance. The principles of their repair differ from those applied to central facial units. The correct restoration of skin quality, not outline or three-dimensional contour, determines success.


Unlike a nasal wound, a moderate forehead defect can be allowed to heal secondarily. The resulting shiny, flat scar, supported by the underlying rigid bony platform of the skull, blends into the normal shiny, tight surface of the forehead without significant distortion or malposition of adjacent landmarks. Rarely, a skin graft may be used to replace the entire forehead unit or a lateral subunit, after discarding any residual skin within the unit. The uniform, shiny quality of the skin graft simulates the expected skin quality and contour of the entire unit or subunit, masking its peripheral scars along the hairline, brow, or contour lines between the lateral and central forehead subunits.


Most often, the lax and excess adjacent skin within the cheek is shared by resurfacing the defect with a nonsubunit rotation advancement flap. Enlarging the wound so that the entire forehead or cheek is recovered with one flap is impractical due to the paucity of available donor excess and the unreliability of flap blood supply. The subunit principle is rarely applied when resurfacing the cheek or forehead.




Principles of regional unit repair25,28




When part of a central convex nasal unit is missing, it is often useful to resurface the entire unit or subunit, rather than simply patch the defect. The wound’s dimension, outline, or depth is altered. Residual tissue within the subunit may be discarded to enlarge the wound. Or the defect may be decreased in size by local advancement rotation flaps, or changed in border outline by a combination of excision and tissue rearrangement. Subunit resurfacing positions scars so that they are camouflaged within the joins between subunits. More importantly, myofibroblasts lie in the recipient bed under a transferred flap and contract, causing the transposed skin flap to raise above the level of adjacent skin. When an entire convex subunit is resurfaced, the pincushioned flap shrinkwraps around the underlying cartilage framework, augmenting, rather than distorting, the contour of a convex subunit.







Choose ideal donor materials and employ an ideal method of tissue transfer


Millard’s admonition to use “like for like” applies.30 Use lip for lip, cheek for cheek, and a forehead or nasolabial flap for nasal resurfacing. Distant tissues are employed for lining, to fill dead space, create a facial platform, or vascularize an ischemic, contaminated, or radiated wound. However, distant skin does not match the facial skin quality. Distant skin is not used to resurface the face. Regional skin should be used to replace facial skin.








Consider a preliminary operation


A preliminary operation, prior to formal nasal reconstruction, can be helpful. Often, the extent of deformity is obscured by the effects of secondary healing or prior skin grafts or flaps. The defect is recreated and residual tissues returned to their normal position. Then the dimension and position of the defect can be better appreciated and the required tissue replacements more accurately defined. Although past history, physical examination, old operative reports, or radiographs may provide information, the extent of the true defect may only become apparent after recreating the defect.


Excision of scar or soft-tissue bulk can open an occluded airway, permitting its raw surfaces to be resurfaced with a skin graft or local flap. Residual local tissue or adjacent regional flaps can be positioned for later use or surgically delayed to maximize blood supply, especially when scar lies within the territory or injury to the flap’s pedicle is suspected. Ischemic or chronically infected tissue may require debridement. Immature tissues are allowed to revascularize, soften, and stabilize. Defects of the lip and cheek may be repaired, establishing a stable platform on which to place the nose at a later date. If indicated, the wound can be biopsied to ensure complete clearance of tumor or immune disease remission.


When a defect is complex, the patient may be anxious and the surgeon uncertain of tissue needs or available options. The diagnosis may need clarification, the wound need preparation, or the problem need to be analyzed to prepare a comprehensive plan. Use time to advantage.



Classification of defects


The requirements and difficulty of repair are determined by the site, size, and depth of injury. Nasal defects are classified into small, superficial, large, deep, or composite defects.22,25









Treatment/surgical technique and postoperative care


Although “simple” at first glance, small and superficial defects are difficult to repair. Surgeons and patients fail to appreciate the complexity of nasal contour, the paucity of excess tissue, the difficulty of matching the remaining skin in color and texture, and the risk of distorting the residual mobile tip and nostril margins. Many options are available. The time, trouble, morbidity, donor and recipient scars, number of stages, time to wound maturity, and cost must be balanced against the likelihood of secondary deformity.



Zones of nasal skin quality


The nose is covered by skin and an underlying layer of subcutaneous fat and nasalis muscle which lie over a rigid bony elastic framework of cartilage and fibrofatty support. However, the quality of the skin is not uniform, unless the skin is atrophic due to old age, sun injury, or radiation injury. In the normal nose, it can be divided into areas of thin smooth skin and thickly pitted skin. Note that the zones of skin quality do not correspond to the nasal units, which are defined by contour.


In the superior half of the nose, the skin of the dorsum and sidewalls is thin, smooth, pliable, and mobile. A modest excess of skin is present, which permits primary closure or a local flap to close small defects without distortion of adjacent mobile landmarks. A modest amount of skin can also be recruited from the cheek to close a small sidewall or alar defect. Although a simultaneous rhinoplasty, hoping to decrease the size of the nasal skeleton and relatively increase the available skin, has been recommended to ease the closure of small defects in a large nose, this is rarely helpful.


The inferior half of the nose is covered by a zone of tight skin, pitted with sebaceous glands, and adherent to the underlying deep structures. The thick skin zone begins in the alar grooves, crosses 5–10 mm above the supratip region, and extends inferiorly towards the caudal borders of the tip and alar subunits. About 2–3 mm above the alar margins and a few millimeters below the outermost point of the tip and on to the columella, the skin thins and loses its sebaceous quality. The lower half of the infratip lobule, including the soft triangle and columella, is covered by thin, but adherent, skin fixed to the underlying structures. The tip and alar margins are mobile and easily distorted by contracting scar or inaccurate tissue replacement.



Restoring nasal cover



Small, superficial defects



Healing by secondary intention


The body responds to injury by epithelialization, the formation of granulation tissue, and myofibroblast contraction. The process is simple, inexpensive, somewhat slow, but often satisfactory.


Healing by secondary intention is recommended for wounds created by a destructive process which precludes primary closure. These include electrodesiccation and curettage or those associated with wound dehiscence, infection, or necrosis. To avoid further injury due to desiccation or trauma, secondary healing is not employed if vital deep structures are exposed in the base of the wound.


No net gain in tissue occurs with secondary healing. Wound contraction progresses only to the degree that adjacent tissue can be pulled into the defect. The residual gap is filled with collagen covered with a shiny adherent thin layer of epidermis, containing few melanocytes or skin appendages. The result is a pale, shiny, flat, white scar. Secondary healing may be employed for defects which lie within a flat or concave nasal surface, at a distance from mobile landmarks, especially when they lie within sun or radiated injured skin where imperfections of skin quality due to spontaneous healing are less apparent.


A small superficial defect of the flat tight dorsum, sidewall, or deep alar crease may heal satisfactorily by secondary intention. However, imperfections in color or texture or contour depressions are visible in the thicker skin of the tip and ala. The mobile tip and nostril margins are also at risk for distortion due to scar contracture.


Despite limitations, almost any wound will heal spontaneously, if medical illness, cost, lifestyle, or lack of patient interest precludes a more formal repair. If the patient is unhappy, repair in the future.




Skin grafting


Skin grafts have many advantages.22,25 No new scars are added to the nasal surface and the amount of locally available excess tissue is not a limiting factor. Skin grafts are typically harvested from preauricular, postauricular, or supraclavicular donor sites.


However, a skin graft must lie on a well-vascularized bed to ensure “take” and will not reliably survive when placed on denuded cartilage or a cartilage graft. Bare cartilage must be covered with a vascularized flap. A skin graft, placed over a narrow primary cartilage graft, may revascularize by the bridging phenomenon; however, this is a risky technique. The size of the cartilage graft must be limited. Complete or partial skin graft necrosis may occur.


The aesthetic result of skin graft is unpredictable. Because of the transient ischemia which accompanies skin graft transfer, the quality of donor skin deteriorates. Skin grafts often appear pale, smooth, and atrophic. Postauricular skin may remain red. Supraclavicular skin appears brown and shiny. The hairless patch between the tragus and sideburn provides a better match, especially when applied to the dorsum, sidewall, or columella.


The traditional full-thickness skin graft may blend satisfactorily into the relatively smooth atrophic upper nose within the thin skin of the dorsum and sidewall. However, traditional skin grafts, within the zone of thick skin zone of the tip and ala, often appear as depressed, shiny, off-colored patches, unless the skin of the recipient site is atrophic due to sun injury or radiation.




Full-thickness forehead skin graft (Figs 6.2–6.6)






Although not traditionally transferred as a skin graft, forehead skin is useful for resurfacing small superficial defects, especially of the tip and ala. Forehead skin is acknowledged as the best match to replace nasal skin. Forehead skin and its underlying compact fibrofatty subcutaneous layer are thicker and stiffer than other donors. Significant amounts of soft tissue can be carried with the graft, permitting the replacement of the deeper soft tissues. Forehead skin grafts revascularize normally, with progressive changes in color from white to blue to pink. A good take is routinely expected. However, when failure seems imminent, the clinical evolution of the forehead skin graft is unique. Unlike grafts harvested from other sites, early separation does not occur. A hard and tightly adherent eschar develops and should be left undisturbed and not debrided. It may remain fixed to the underlying tissues for 4–6 weeks. After spontaneous separation, the surgeon often finds that the wound is healed, filled, and the aesthetic result is good. One to 1.5 cm of forehead skin is easily harvested below the frontal hairline with primary closure of the donor site. The scar is usually excellent and easily covered by hair.





Skin graft technique


A skin graft must be placed on a vascular bed to ensure “take.” It must be in direct contact and will not survive if tented across the defect or separated by hematoma or seroma. It must be immobile to allow the development of vascular connections to the recipient site.


Excessive coagulation of the recipient site is avoided, if possible. It is often helpful to delay skin grafting for 10–14 days to allow spontaneous separation of electrical burn eschar and the development of granulation tissue. The recipient site is protected from desiccation by daily cleansing with soap and water and multiple applications of antibiotic or petrolatum ointment to prevent drying out of the soft tissues, periosteum, or perichondrium. The skin graft is then applied as a delayed primary graft, avoiding exposure of the underlying cartilage during preparatory debridement.


A pattern is made of the defect prior to debridement. The margins and base of the wound are freshened to create a clean, sharp, right-angle skin edge and a vascular bed. Old scar, skin graft, or granulation tissue is removed. A pre- or postauricular skin graft is elevated in the subcutaneous layer and a forehead skin graft over the frontalis muscle. Fat is removed from the undersurface of the graft with curved scissors, but the graft is not necessarily thinned to dermis. The thickness of skin graft and its underlying fat should match the depth of recipient site. The graft is laid on the prepared bed, trimmed, and inset with a single layer of fine sutures, peripherally. Quilting sutures are placed through the skin graft and into the recipient bed to prevent lateral motion. A layer of antibiotic ointment and fine gauze is applied, followed by a soft foam bolus. Traditionally, individual bolus tie-over sutures are fixed to the wound edge and tied over the bolus dressing to each other. However, it is quicker and more efficient to tie a single 4-0 or 5-0 polypropylene suture about 5–10 mm from the wound edge and then criss-cross back and forth across the bolus in a running fashion. With each pass, the needle takes a bite of skin several millimeters away from the wound edge, finally tying the suture to itself. The surgeon only clips the suture in one or two areas to remove the dressing easily.


The stent dressing immobilizes the skin graft postoperatively and reinforces the quilting sutures. However, it is not a “pressure” dressing and should not be applied to stop bleeding or prevent hematoma. Initially, the skin graft appears white. Over several days, perfusion increases and the graft changes color from blue to visibly pink. Although the bolus can be removed earlier, it is best left in place for 1 week. If the defect is repaired delicately with fine sutures and without tension, suture marks do not occur.



Local flaps


Unlike a skin graft, the quality of skin transferred as a vascularized flap maintains its original quality. So the color and texture of flaps are predictable. A skin flap is also thicker than a graft and may better supply missing subcutaneous bulk.


An excess of skin is present within the more mobile upper “thin” skin zones of the dorsum and sidewall and can be shared from an area of excess to one of deficiency. But there is no excess within the “thick” skin zone of the tip and ala.


Remember that local flaps add no new skin but simply share the available, but limited, excess within the upper nose to an area of deficiency. If the defect is larger than 1.5 cm, the remaining skin surface is insufficient to redistribute over the nasal skeleton without excess closure attention and distortion of mobile landmarks. Guidelines, applicable to almost all local nasal flaps, should be followed carefully. Local flaps are used for small superficial defects, greater than 5–10 mm from the nostril margins and above the tip defining points. Commonly described local flaps will not reach into the infratip area. Unfortunately, these rules are often broken, leading to nasal collapse, tip and alar margin malpositions. To avoid the morbidity or stages required by regional flaps, local flaps may be used inappropriately to resurface large defects or those near the tip or rim. In such instances, it would be better to allow the wound to heal secondarily or apply a skin graft.



The single-lobe transposition flap (Fig. 6.7)


A modest amount of excess mobile and lax skin is available within the superior nose. A single-lobe transposition flap, designed as a Banner or Romberg flap, is useful for small open defects.33,34 These flaps transpose skin through an arc of 90°, taking excess from one axis to fill a deficiency in another. Because the skin in the superior nose is relatively mobile, available, and lies at a distance from the nostril margins, these small local flaps are unlikely to distort the tip or alar margin. However, if the flap donor scar crosses the bridge transversely, a depressed scar may become visible on profile view. Single-lobed flaps are not useful in the inflexible thick skin of the tip or ala, which shifts poorly. Deforming dog-ears or displacement of adjacent mobile landmarks are common.




The dorsal nasal flap


The dorsal nasal flap elevates skin, subcutaneous tissue, and muscle just above the perichondrium and periosteum and slides excess from the glabella towards the tip. The flap is best applied to defects within the dorsum and superior tip subunit.3537 It is vascularized from facial and angular vessels along the sidewall and medial canthus. Closure is facilitated by advancing cheek skin upward on to the nasal sidewall. The dorsal nasal flap can resurface the nasal tip and dorsum and parts of the ala or sidewall with local skin. Unfortunately, it slides thicker glabellar skin and soft tissue downward on to the nasal sidewall near the medial canthus where a mismatch in skin thickness may create an iatrogenic epicanthal fold. The depth of the radix may be obliterated, effacing the nasal root. Recent modifications have eliminated the glabellar extension. As the dorsal flap slides caudally, a dog-ear is excised inferiorly. Ideally, its borders are planned to lie along the dorsal sidewall junction. The inferior aspect of the flap’s border may be visible as a depressed scar crossing the smooth surface of the tip unit. Like all local flaps, the larger the defect and the closer it lies to the nostril margin, the more likely the tip or rim will be distorted by tension or displaced by poor design.



The geometric bilobed flap


The bilobed flap is recommended for defects within the thick, stiff skin of the inferior nose.


The bilobed principle is applied.3840 Skin is shifted from an area of excess to an area of deficiency by designing the first lobe adjacent to the tip or alar defect. A second lobe, which lies at a distance in an area of tissue availability within the upper nose, is outlined in continuity. As the primary lobe shifts to repair the defect, the secondary lobe resurfaces the defect from the primary lobe. The tertiary defect from the second lobe is closed primarily, within the area of excess.


Traditionally, bilobed flaps were designed with 180° rotation. This created large dog-ears. The dog-ear excision narrowed the flap’s vascular base, jeopardizing blood supply. McGregor and Soutar,39 and later Zitelli,40 developed a geometric design to decrease the flap’s rotation to 90–100° and incorporated a dog-ear excision which did not diminish blood supply. It is useful for defects measuring 0.5–1.5 cm in the inferior nose.


The rotation-advancement flap can be oriented anywhere around the defect but the pedicle base must be positioned away from the nostril margin to prevent distortion. The second lobe must also lie within the loose excess skin of the upper sidewall or dorsum. It can be based medially or laterally. The pattern should not extend on to the cheek or lower lid.


Several rules apply:



1. The pivot point is established at a distance from the defect equal to one-half of the defect’s diameter (or the radius of the defect). The flap is based laterally for tip defects and medially for defects of the alar lobule. The further the pivot point away from the defect, the larger the flap. Sharing the same pivot point, the circumferences of a larger outer and smaller inner concentric circle are drawn on to the nasal skin. The circumference of the outer circle is outlined at a distance three times the radius of the defect. The second smaller inner circle is marked to equal the distance from the pivot point to the center of the initial defect (the diameter of the defect). Because the nasal surface is round, not flat, a strip of foil or bent paper ruler, rather than a straight ruler, is used as a template which is rotated around the pivot point, like individual spokes of a wheel, until the circumference of both concentric circles is determined.


2. An exact pattern of the circular nasal defect is positioned immediately adjacent to the defect, along the outer concentric circle. The first lobe should replace the defect exactly, to prevent tip or alar rim distortion on closure. Because the second lobe lies within the more mobile skin of the upper nose, it can be designed slightly smaller than the defect. The secondary defect can be partially closed by recruitment of lax adjacent skin within the upper nose. A dog-ear excision, which extends lateral to the outer circle, is added to the second lobe.


A dog-ear excision is marked from the defect to the pivot point, creating space for the flap to rotate and advance. The flap rotates less than 100° with a wide base to maintain flap blood supply.


3. The dog-ear extending from the defect of the pivot point is excised. The first and second lobes, including the distal dog-ear, are elevated above the periosteum. The flap includes skin, subcutaneous fat, and nasalis muscle. Residual normal nasal skin is undermined widely over the perichondrium and periosteum.


4. Significant pincushioning is infrequent with the bilobed flap, if it is carefully repaired, in layers. The tertiary defect, in the more mobile upper nose, is closed in layers. This pushes the flap inferiorly, preventing the tendency of the flap to return to its donor site. The primary lobe, after appropriate “thinning” so that its skin surface will match the level of the adjacent normal skin, is transferred to the primary defect. The secondary lobe is transposed to fill the gap created by the first. Each flap is fixed in place with sutures to approximate muscle, the subcuticular layer, and skin.


Unfortunately, even with careful intraoperative planning, postoperative tip or nostril distortion is common, especially when the defect lies within the tip or ala. Although planned as a single-stage repair, it is not uncommon to revise scars, recreate the obliterated alar crease, or reposition the nostril margin.


The geometric bilobed flap is effective. But it should be limited to defects of the tip which are less than or equal to 1.5 cm in diameter and which lie more than 1 cm away from the nostril margin. This precludes its use for significant alar defects. Despite the relatively small size of these defects, the technique is time-consuming, the dissection extensive, scars multiple, swelling significant, and distortions common.



The one-stage nasolabial flap (Fig. 6.8)




The one-stage nasolabial flap can resurface defects of the nasal sidewall and ala, up to 2 cm in size.25 Excess skin of the medial cheek, lateral to the nasolabial fold, is transferred as a random-pattern extension of an advancing cheek flap. Unlike local flaps which redistribute residual nasal skin, this technique “adds” regional cheek skin to the nasal surface. This minimizes the risk of landmark distortion and permits the use of alar support grafts without fear of collapse due to excessive tension.




1. The sidewall and alar subunits are outlined in ink. Alar subunit excision is not performed but skin, which remains between the defect in the inferior nostril rim, can be excised, enlarging the defect inferiorly to the nostril margin. This positions the scar along the nostril border and improves the flap’s blending with the recipient site. The underlying lining is braced with a septal or ear cartilage graft to prevent collapse or retraction of the nostril margin. The ends of the cartilage graft are buried, medially and laterally, in subcutaneous pockets along the rim and at the alar base, and fixed with percutaneous 5-0 polypropylene sutures. The cartilage graft is quilted to the underlying lining to fix the support graft and brace the nostril margin.


2. The nasolabial crease is marked and a pattern of the defect is positioned exactly adjacent to the nasolabial fold so that the late cheek scar lies exactly in the nasolabial crease. A dog-ear excision is marked inferiorly, distal to the template. Ensure that the sliding cheek advancement has adequate length to swing and correctly position the nasolabial extension on to the nasal defect. The most important flap dimension is width, which should equal the width of the defect. The distal margin of the flap will be trimmed during wound closure and does not need to be predetermined. The flap is elevated in continuity with the distal dog-ear. The superior lateral incision for the alar or sidewall flap extension should not extend higher than the alar remnant that must be “jumped over” to reach the recipient site. A higher incision is unnecessary and may impair blood supply.


3. The nasolabial skin extension and the cheek flap are undermined, with a few millimeters of subcutaneous fat, laterally for 3–5 cm. The cheek is advanced, fixing its underlying raw surface to the deep tissues along the nasal facial groove. This suture fixation advances the cheek flap, closes the donor defect, and restores the nasofacial sulcus. It eliminates lateral and vertical tension on the nasolabial extension, which travels with a cheek flap to resurface the primary defect. The vascularity of the random extension is good, but can be impaired by tension.


4. Excess subcutaneous fat is excised to match the thickness of the flap to the depth of the recipient bed. Absorbable sutures can be placed to fix the deep surface of the flap gently to the underlying soft tissues at the ideal alar crease, if vascularity is maintained. If necessary, the crease can be recreated secondarily. The distal flap is gently laid over the inferior aspect of the nasal wound and trimmed to fit. The incisions are closed in layers.


Final scars blend within the sidewall or lie in the nasolabial fold. Pincushioning of this nonsubunit skin replacement can occur, but is minimized if the ala is supported and braced by primary cartilage grafts to control nostril margin shape and position.


The one-stage nasolabial flap is useful for defects of the sidewall and ala which are not effectively repaired with other local flaps. It can also be used to resurface the upper lip and nasal sill in a composite defect of the nose, lip, and cheek.4143 It is often combined with the Millard fat flip flap,15,16 which hinges over excess subcutaneous fat, from the lateral cheek, to restore missing premaxillary soft-tissue bulk.



Large, deep, and adversely located defects



The superiorly based two-stage subunit nasolabial flap (Figs 6.9–6.11)





The two-stage nasolabial flap22,44 transfers excess skin from the medial cheek, just lateral to the nasolabial fold, supplied by blood vessels which originate from the underlying facial and angular arteries, passing through the underlying subcutaneous tissue, above and below the levator labii muscle. Although the narrow skin pedicle contributes a modest random blood supply, the flap is a subcutaneously based island flap. If the underlying subcutaneous vascular base is intact, the flap is reliable even if skin lateral to the ala is scarred or has been excised. The subcutaneous pedicle permits easy transposition and the narrow skin component eliminates the superior dog-ear and its accompanying scar from extending on to the nasal sidewall on wound closure. The flap is designed with its medial border exactly along the nasolabial fold to place the final scar exactly in the nasolabial crease. In young patients or those with a poorly defined fold, the nasolabial crease may be indistinct and should be marked with ink preoperatively, before sedation or general anesthesia.



A two-stage nasolabial flap is best employed to resurface the convex ala as a subunit. Residual skin within the alar subunit is excised so that the entire subunit is resurfaced, rather than just patched.




Stage 2

Three weeks later, the pedicle is divided. Skin is re-elevated with 2–3 mm of fat over the lateral aspect of the alar inset. Underlying subcutaneous fat and scar are excised, sculpting a convex alar contour and a defined alar crease. The flap is reapproximated to the recipient site. The superior aspect of nasolabial cheek scar is reopened, excess skin and soft tissue excised, and the cheek closed.


Practically speaking, the nasolabial flap has a limited role in nasal reconstruction. Because of the limited excess available in the medial cheek, there is only enough nasolabial tissue to resurface a defect of about 2 cm in width. Although this is a reliable flap, excessive undermining or tension may lead to necrosis. It will not reliably revascularize a skin graft for lining or maintain its blood supply if folded for cover and lining. Its arc of rotation and reach are limited. It can be transposed to the ala, columella, or to resurface the upper lip but it will not safely reach the tip or dorsum. Although a nasolabial flap scar may be hidden in the nasolabial fold, the cheek becomes flattened and may necessitate a contralateral excision of medial cheek tissue to improve symmetry with the opposite cheek. A nasolabial flap routinely transfers beard in the male.

Feb 21, 2016 | Posted by in General Surgery | Comments Off on Aesthetic nasal reconstruction
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