Rhinoplasty - Surgical Précis For Rhinoplasty - Surgical Management

Surgical Management

The following rhinoplastic techniques are applied to the surgical management of: (i) partial-thickness defects; (ii) full-thickness defects; (iii) heminasal reconstruction; and (iv) total nasal reconstruction.

I. Partial-thickness defects

A partial-thickness defect is a wound with adequate soft-tissue coverage of the underlying nasal skeleton, yet is too large for primary intention closure, with sutures. Based upon the locale of the wound, the surgeon has two (2) options for correcting such a wound: (i) healing the wound by secondary intention (re-epithelialisation); and (ii) healing the wound with a full-thickness skin graft. Moreover, because it avoids the patched appearance of a skin-graft surgical correction, healing by secondary intention can successfully repair nasal wounds up to 10 mm in diameter; and, if the resultant scar proves aesthetically unacceptable, it can be revised later, after the wound has healed.

In the event, larger nasal wounds (defects) do successfully heal by secondary intention, but do present two disadvantages. First, the resultant scar often is a wide patch of tissue that is aesthetically inferior to the scars produced with other nasal-defect correction techniques; however, the skin of the medial canthus is an exception to such scarring. The second disadvantage to healing by secondary intention is that the contracture of the wound might distort the normal nasal anatomy, which can lead to a pronounced deformity of the alar rim area. For this reason, healing by secondary intention generally is not recommended for defects of the distal third of the nose; nonetheless, the exception is a small wound directly upon the nasal tip.

Full-thickness skin grafts are the effective wound-management technique for defects with a well-vascularized, soft-tissue bed covering the nasal skeleton. The patient’s ear is the preferred skin-graft donor site from which to harvests grafts of pre-auricular skin and grafts of post-auricular skin, usually with an additional, small amount of adipose tissue to fill the wound cavity. Yet, nasal correction with a skin graft harvested from the patient’s neck is not recommended, because that skin is low-density pilosebaceous tissue with very few follicles and sebaceous glands, thus is unlike the oily skin of the nose.

The technical advantages of nasal-defect correction with a skin graft are a brief surgery time, a simple rhinoplastic technique, and a low incidence of tissue morbidity. The most effective corrections are with a shallow wound with sufficient, supporting soft-tissue that will prevent the occurrence of a conspicuous depression. Nonetheless, two disadvantages of skin-graft correction are mismatched skin color and skin texture, which might result in a correction with a patch-work appearance; a third disadvantage is the natural histologic tendency for such skin grafts to contract, which might distort the shape of the corrected nose.

II. Full-thickness defects

Full-thickness nasal defects are in three types: (i) wounds to the skin and to the soft tissues, featuring either exposed bone or exposed cartilage, or both; (ii) wounds extending through the nasal skeleton; and (iii) wounds traversing all three nasal layers: skin, muscle, and the osseo-cartilaginous framework. Based upon the dimensions (length, width, depth) and topographic locale of the wound and the number of missing nasal-tissue layers, the surgeon determines the rhinoplastic technique for correcting a full-thickness defect; each of the aesthetic nasal subunits is considered separately and in combination.

(a) Medial canthus

The skin between the nasal dorsum and the medial canthal tendon is uniquely suited to healing by secondary intention; the outcomes often are superior to what is achieved with either skin grafts or skin-flaps and tissue-flaps. Because the medial canthal tendon is affixed to the facial bone, it readily resists the forces of wound contracture; moreover, the animation (movement) of the medial brow also lends resistance to the forces of wound contracture. Furthermore, the medial canthal region is aesthetically hidden by the shadows of the nasal dorsum and of the supraorbital rim, thereby obscuring any differences in the quality of the color and of the texture of the replacement skin (epithelium).

Healing by secondary intention (re-epithelialisation) occurs even when the wound extends to the nasal bone. Although the rate of healing depends upon the patient’s wound-healing capacity, nasal wounds measuring up to 10 mm in diameter usually heal in at 4-weeks post-operative. Nonetheless, one potential, but rare, complication of this nasal correction approach is the formation of a medial canthal web, which can be corrected with two (2) opposing Z-plasties, technique which relieves the disfiguring tensions exerted by the scar tissue’s contracture, its shape, and location on the nose.

(b) Nasal dorsum and lateral nasal wall defect

The size of the nasal defect (wound) occurred, in either the dorsum or the lateral wall, or both, determines the reconstructive skin-flap technique applicable to the corresponding aesthetic nasal subunits.

• A wound of less than 10 mm in diameter can be managed either by primary intention healing (suturing) or by secondary intention healing (re-epithelialisation).

• A wound measuring 10–15 mm in diameter can be reconstructed with a single-stage modified bilobed flap, because it best matches the skin color and the skin texture of the wounded aesthetic subunit. Although not every scar can be hidden at the margins of the aesthetic nasal subunits concerned, the superior scarring ability of those nasal skin areas minimizes such an histologic disadvantage. In a patient whose basal-cell carcinoma was excised with Mohs surgery, the scar of the nasal reconstruction (an 11 mm full-thickness, laterally based, bilobed-flap applied down to the bone and the cartilage), was hidden by aligning the axis of the second lobe to and emplacing the skin graft at the junction of the nasal dorsum and the lateral wall of the nose.

• A wound greater than 15 mm in diameter can be corrected with a paramedian forehead flap, which will reconstruct either the entire nasal dorsum or the lateral wall of the nose, as required. The surgical management of such wounds (< 15 mm dia.) usually requires enlarging the wound as necessary, in order for the skin graft to comprehend the entire aesthetic subunit being corrected. Moreover, if the wound comprehends the dorsum and the lateral wall of the nose, then a cheek-advancement skin flap is the applicable correction for replacing the lateral nasal skin up to its junction with the dorsum; afterwards, a paramedian forehead flap is applied to resurface the nasal dorsum.

• A wound in the lateral nasal wall that is greater than 15 mm in diameter can also be corrected with a superiorly based, nasolabial-flap, which is especially suited for correcting distal defects that lay among the convexities of the nasal tip and the alar lobule. The nasolabial flap can correct defects that comprehend the distal two-thirds of the nose, if there is a supply of skin sufficient for constructing the base of the flap pedicle; and the donor sites cannot be closed primarily. Yet, bulkiness is the principal disadvantage of the nasolabial flap — except in elderly patients with atrophic cheek skin; nonetheless, it is technically effective for patients unsuitable for a two-stage rhinoplasty with a paramedian forehead flap.

• Nasal defects involving either the bone or the cartilage of the lateral nose are best managed with free grafts of flat septal bone and of cartilage. Small defects of the nasal dorsum can be covered with cartilage grafts harvested from either the septum or the concha of the ear. The correction of large-area defects of the nasal dorsum requires the stable support of a bone graft affixed either with a lag screw or with a low-profile plate. A costal graft (from the rib cage) is ideal for such a repair, because it can be harvested with an attached extension of cartilage that can be sculpted to blend into the nasal tip; other potential donor sites for nasal dorsum reconstruction materials are the outer table of the skull, the iliac crest, and the inner table of the ilium proper.

• To correct a defect of the nasal lining of the upper two-thirds of the nose, the wound dimensions (length, width, depth) determine the technique. A nasal-lining defect of less than 5 mm in diameter can be closed primarily, with sutures. A nasal-lining defect 5–15 mm in diameter can be closed with a random transposition flap harvested from a nasal area that remains protected, either by the nasal bones or by the upper lateral cartilages; and the flap donor-site can be healed by secondary intention, re-epithelialisation. For a mucosa defect greater than 15 mm in diameter, the indicated correction is a superiorly based “trap door” septal mucosal flap, grafted to the roof of the nasal septum.

(c) Nasal tip defect

The width of the human nasal-tip ranges 20–30 mm; the average width of the nasal tip, measured between the two alar lobules, is approximately 25 mm.

• A nasal skin defect of less than 15 mm in diameter can be managed with a bilobed flap; the surgeon trims the edges of the wound (defect) to match its dimensions (length, width, depth) to the natural curve at the border of the nasal tip. If the wound is eccentric, the skin-flap is positioned so that the lateral base of the graft occupies the largest portion of the wound’s surface.

• If the nasal-tip wound is greater than 15 mm in diameter, the surgeon enlarges it to comprehend the entire aesthetic subunit affected by the defect, and the reconstruction of the nasal subunit done with a forehead flap. If the nasal-tip defect also involves the nasal dorsum, a forehead flap is indicated for reconstructing the entire nasal-tip and dorsum.

• If an alar cartilage is missing, either partially or entirely, it is reconstructed with cartilage grafts. The defect of an alar dome, which retains adequate anatomic support-tripod configuration, can be corrected with an onlay graft harvested either from the nasal septum or from the conchal cartilage of an ear. The surgeon forms the cartilage graft into the shape of a shield — its widest margins become the replacement alar domes. Typically, the shield cartilage graft is stacked in two layers, in order to transmit the desired light reflex characteristic of the nasal tip.

• Defects of the lateral crura can be corrected with a flat strut of formed cartilage, but, if the support of the medial crura is absent, then a columella strut must be inserted, and attached at the level of the anterior nasal spine. If a strut of nasal-septum cartilage proves too weak, then a rib cartilage strut can be applied to provide the adequate nasal support; afterwards, the strut is covered with onlay grafts.

• Absent alar cartilages can be replaced using all of the conchal cartilage from both ears; two strips, each 10 mm wide, are harvested from the antihelical fold, and then are applied as replacement alar wings. The surgeon attaches them to the anterior nasal spine, and to each side of the (pear-shaped) pyriform aperture; the remainder of the harvested conchal cartilage is applied as onlay grafts to augment the nasal tip.

• A nasal-tip lining defect is unusual, because of its midline location; yet, the reconstruction is with an anteriorly based septal mucosal flap that is rotated into place to provide adequate coverage and correction of the nasal lining defect.

• Vertical lobule division (VLD) is a common technique for nasal tip refinement, which involves the medial crural angle and the lateral crural angle.

(d) Alar lobule defect

The appropriate surgical management of an alar lobule defect depends upon the dimensions (length, width, depth) of the wound. Anatomically, the nasal skin and the underlying soft tissues of the alar lobule form a semi-rigid aesthetic subunit that forms the graceful curve of the alar rim, and provides unobstructed airflow through the nostrils, the anterior nares.

• When most of the alar lobule tissue is missing, the nose collapses; the correction is with an ear concha cartilage-graft harvested from the antihelix, a donor site where the cartilage is most rigidly curved, thus is ideal for replacing an alar lobule.

• Nasal skin defects can be corrected with a medially based bilobed flap, which is emplaced to provide adequate skin coverage for wounds limited to the alar lobule. If the entire lobule is missing, it might be necessary to leave the second-lobe donor-site wound partially open; it will close at 2–4 weeks post-operative; afterwards, the scar can be revised. Nonetheless, the alternative surgical correction is a two-stage, superiorly based, nasolabial flap.

• If the alar lobule defect also comprehends the lateral wall of the nose, the defect can be closed either with a superiorly based nasolabial-flap or with a forehead flap. If the cheek skin is thin and atrophic, a nasolabial flap is the recommended reconstruction; otherwise, a forehead flap is recommended, because the thickness of forehead skin is a superior match for nasal skin and tissue. Mucosal lining defects of the alar lobule can be resurfaced with a bipedicled mucosal advancement-flap harvested from inside the lateral wall of the nose. Likewise, larger defects of the mucosa do require correction with an anteriorly based septal mucosal flap.

III. Heminasal and total nasal reconstruction

The reconstruction rhinoplasty of an extensive heminasal defect or of a total nasal defect is an extension of the plastic surgical principles applied to resolving the loss of a regional aesthetic subunit. The skin layers are replaced with a paramedian forehead flap, but, if forehead skin is unavailable, the alternative corrections include the Washio retroauricular-temporal flap and the Tagliacozzi flap. The nasal skeleton is replaced with a rib-graft nasal dorsum and lateral nasal wall; septal cartilage grafts and conchal cartilage grafts are applied to correct defects of the nasal tip and of the alar lobules.

The nasal lining of the distal two-thirds of the nose can be covered with anteriorly based septal mucosal flaps; however, if bilateral septal-flaps are used, the septal cartilage does become devascularized, possibly from iatrogenic septal perforation. Furthermore, if the nasal defect is beyond the wound-correction scope of a septal mucosal flap, the alternative techniques are either an inferiorly based pericranial-flap (harvested from the frontal bone) or a free flap of temporoparietal fascia (harvested from the head), either of which can be lined with free grafts of mucosa to achieve the nasal reconstruction.