When it comes to the subject of rhinoplasty, many authors trivialize or overlook the role of nasal skin in cosmetic nasal surgery. Instead, interest is directed at the nasal skeleton and the various methods of modifying the underlying skeletal framework. Although skeletal modification is fundamental to a successful rhinoplasty, the nasal skin and its associated soft tissue components, often called the skin–soft tissue envelope (SSTE), also play a critical role in the surgical outcome. Indeed, for a small subset of rhinoplasty patients, soft tissues may prove the limiting factor in creating a more beautiful nose. At the very least, it is the nasal SSTE that transforms the unfamiliar shape of the raw nasal skeleton into the refined and elegant outer contour of an attractive human nose. Moreover, this transformation is far from simplistic. Owing to site-specific variations in skin thickness within the nose, the skin’s contribution to nasal topography is nonlinear and indirect, making cosmetic nasal surgery a translational activity—exponentially more challenging than directly sculpting an object’s surface contour. Furthermore, because the SSTE is susceptible to the capricious effects of contracture, fibrosis, and edema, unforeseen skin changes can alter the intended nasal contour and compromise the otherwise well-executed operation. In rare but extreme cases, soft tissue healing aberrations may become so severe as to negate the skeletal modifications entirely, resulting in even greater cosmetic deformity. Hence, to ignore the importance of the SSTE in cosmetic nasal surgery is to disregard a critical component of the surgical outcome.
Variations in Skin Type
While skin of any type can potentially spoil the rhinoplasty outcome, it is generally skin types on the extreme limits of thickness that are the most challenging for the cosmetic nasal surgeon. In patients with extremely thin nasal skin, the atretic covering offers scant camouflage or concealment, and the surgeon must render a flawless underlying skeletal contour to prevent visible imperfections in the surface topography. Moreover, both telangiectasias and dyschromias are easily provoked with surgical dissection of thin nasal skin. On the other hand, delicate skin is generally much less prone to edema or excessive fibrosis, and skin incisions tend to heal favorably in thin-skinned individuals. In fact, the thin-skinned rhinoplasty patient will often experience a shorter-than-average length of recovery with far less soft tissue distortion.
In contrast to the thin-skinned nose, extremely thick nasal skin conceals all but the most conspicuous imperfections of the underlying nasal skeleton. However, the advantages of ultra-thick skin end there. In fact, excessive skin thickness is often regarded as one of the most formidable, and sometimes insurmountable, obstacles in cosmetic rhinoplasty. The reasons for this sinister distinction are numerous, and the hazards of thick nasal skin have prompted many surgeons to avoid treating this challenging patient population altogether. However, as ethnic diversity continues to increase throughout the United States, thick-skinned patients have become an increasingly prevalent segment of the rhinoplasty consumer demographic. Moreover, the growing popularity of cosmetic nasal surgery in places like South America and Asia, where thick nasal skin is common, ensures that thick-skinned patients will become more prevalent worldwide. Without question, the thick-skinned rhinoplasty patient will be seen with greater frequency in the future, and demands for effective ethnically appropriate outcomes will increase accordingly.
Anatomy of Nasal Skin
Histologic analysis of nasal skin reveals most of the same components and structures found elsewhere in the integument. However, several important differences are worth noting. Without question, the most profound difference is a discrete fibromuscular tissue layer that separates the nasal skin from the underlying skeletal framework. Comprised largely of skeletal muscle, this fibromuscular layer is functionally and anatomically analogous to the superficial musculoaponeurotic system (SMAS) seen elsewhere in the face. Dubbed the “nasal SMAS,” this fibromuscular layer also varies in thickness according to the individual skin type. In the thin-skinned nose, pores are small and both the dermis and the nasal SMAS are thin and delicate. In contrast, large pores and modest dermal thickening are often observed in thick-skinned noses. However, robust hypertrophic thickening of the nasal SMAS layer is considered to be the underlying cause of the thick-skinned nose. In fact, hypertrophy of the nasal SMAS can more than double the thickness of normal nasal skin. Fortunately, the nasal SMAS is also a discrete tissue layer that can be excised with relative ease—a key feature in surgical management of the ultra thick-skinned nose.
Although dermal thickening and muscle hypertrophy are frequently observed in the thick-skinned nose, these characteristics are seldom distributed evenly ( Figure 27-1 ). For example, hypertrophy of the nasal SMAS is typically most prominent in the nasal tip and immediate surroundings. In contrast, very little muscle hypertrophy is observed at the rhinion or columella, even in patients with ultra-thick skin. In the same way, fat is also more abundant in the thick-skinned nose. However, fat makes little contribution to overall flap thickness except in the nasal root and supratip regions. In conclusion, all noses have site-specific variations in flap thickness, but thick-skinned noses tend to have more fat, a thicker dermis, and markedly thickened fibromuscular tissues with comparatively few areas of thin, pliable soft tissue covering.
Physical Limitations of the Thick-Skinned Nose
As a consequence of its physical bulk and added weight, thick nasal skin poses a formidable challenge for the rhinoplasty surgeon. Perhaps the foremost challenge is the loss of surface definition created by masking of the underlying skeletal framework. Because thick nasal skin more effectively obscures topographic features of the underlying nasal skeleton, the delicate surface undulations which characterize a well-defined and attractive nose are lost. Moreover, a weak and underprojected nasal framework only serves to exacerbate the loss of surface highlights.
In addition to skeletal masking, ultra-thick nasal skin also burdens the cartilage framework with added weight relative to a thin nasal covering. Surgical modifications that undermine structural support are ill-advised, especially in thick-skinned noses, since progressive skeletal collapse and nasal deformity often ensue. Instead, cosmetic modifications must be accompanied by structural reinforcement to ensure both an attractive outer contour and a skeletal framework that can permanently support the added burden of bulky nasal skin. Indeed, without a sturdy and structurally secure cartilage framework, a stable and more refined nasal contour is virtually impossible. Although rigid skeletal support does not by itself ensure a more beautiful nose, a strong nose with ample structural support is the first and foremost requirement for cosmetic enhancement in the thick-skinned patient.
In addition to safeguarding against structural collapse, a well-proportioned and rigid skeletal framework also facilitates stretching of the nasal skin to further refine the surface contour. Stretching the nasal tip skin over a stiff and slightly longer skeletal framework improves surface definition by tightening, and thus thinning, the bulky skin envelope. Although increases in nasal length or tip projection can potentially improve surface highlights, cosmetic gains require not only a sturdy skeletal framework, but also a readily distensible skin envelope. Indeed, without adequate skin elasticity , forceful attempts to tighten the skin envelope may produce unsightly skeletal distortion and/or excessive skin tension. In the thick-skinned nose with dermal thickening, the resulting inelasticity often restricts skin stretching and prohibits optimal contour refinement. In extreme cases, severely inelastic skin may even prevent desired increases in tip projection or nasal length. However, not all thick-skinned patients suffer from inelasticity. In some thick-skinned patients, the skin remains highly distensible despite its thickness, and substantial thinning can be achieved with negligible increases in skin tension. Therefore, skin elasticity does not always correlate with skin thickness, and a careful preoperative assessment of skin distensibility is mandatory for all thick-skinned patients, particularly since skin elasticity is a key determinant of surgical success. Likewise, because nasal skin may become leathery and inelastic following previous nasal surgery, the assessment of skin elasticity is also vitally important in the revision rhinoplasty patient.
Although a taut skin envelope is an important tool in the treatment of the thick-skinned nose, it is not without potential risk. Excessive skin tension may restrict cutaneous perfusion resulting in circulatory compromise or even pressure necrosis when nasal skin is stretched too tightly. The risk of skin injury is increased by preexisting factors that impair nutrient blood flow, such as tobacco use, microvascular disease, or cocaine-induced vascular compromise. Additional factors that may compromise perfusion include excessive use of electrocautery, reckless or extensive tissue dissection, and overly tight compression dressings. Regardless of the situation, nutrient blood flow must be safeguarded by ensuring sustained capillary refill, particularly upon application of a tight compression dressing. Visible signs of vascular insufficiency, such as blanching, loss of capillary refill, or severe venous congestion, should prompt immediate intervention directed at the restoration of nutrient blood flow. Topical vasodilators, such as nitroglycerin paste or topically applied nifedipine, may be useful in treating postoperative vasospasm, but surgical intervention may be needed to reduce skin tension and restore perfusion when conservative measures prove ineffective.
Whereas the cosmetic merits of a rigid skeletal framework and a taut, tightly adherent skin envelope are irrefutable, optimization of surface definition will sometimes require a nose that is aesthetically too large for the face. Although this dilemma has no easy answers, an artfully proportioned and well-defined, if slightly oversized, nose is generally preferable to a smaller, yet amorphous one. In every case, a careful preoperative assessment of skin elasticity, coupled with a frank discussion regarding the limitations of thick skin, is imperative to establish appropriate cosmetic expectations.
Ironically, even though good skeletal support is paramount in the thick-skinned nose, most individuals with overly thick nasal skin also possess soft and exceedingly weak nasal cartilage. This is best exemplified in the platyrrhine nasal morphology known for its broad flat nasal contour. In addition to its hallmark shape, the platyrrhine nose is also characterized by thick inelastic nasal skin, soft underprojected tip cartilages, and a small underdeveloped nasal septum (see Figure 27-1 ). In fact, the distinctive architecture of the platyrrhine nose is widely regarded as one of the most difficult technical challenges in cosmetic nasal surgery. Paradoxically, the unfavorable combination of thick skin and weak cartilage is compounded by the need to substantially increase nasal tip projection in most platyrrhine noses. While the platyrrhine nose is arguably among the most challenging of all anatomic configurations, it is also among the most common nasal morphologies worldwide.