Thin nasal skin readily reveals imperfections of the underlying osseocartilaginous framework and has profound implications for the surgical planning and execution of rhinoplasty. Thin skin may be a normal variant or the result of prior surgery, trauma, or disease. The relative inattention to this subject in the literature is striking, particularly when one considers the small tolerance for error that exists when working with thin skin. One possible explanation is the misconception that relatively few techniques are available to improve surgical results in this difficult group. Another explanation for this conspicuous omission is the prevailing notion that the character of thin skin is largely immutable. This chapter addresses these concerns and introduces a variety of techniques that we have found beneficial in patients with thin nasal skin.
In this discussion, “thin skin” and “thin nasal skin” more properly refer to a thin nasal skin–soft tissue envelope (SSTE). When anatomic reference to the skin of the nose in isolation is intended, we refer specifically to the epidermis, dermis, or cutaneous layer. We have chosen this potentially confusing terminology because most clinicians tacitly include the four layers of tissue between the skin and osseocartilaginous framework when they speak of patients with thin skin. Furthermore, this approach allows us to consider in our discussion of thin skin both patients with naturally fine skin as well as patients who have undergone prior rhinoplasty and have thin SSTEs with a parchment-like character. Several of the technical considerations in these two groups are similar. The aging nose, discussed in a separate chapter, also exhibits thinning of the SSTE and is briefly addressed in this discussion.
Anatomy of the Skin-Soft Tissue Envelope
The anatomy of the SSTE and its relation to the nasal framework is of great interest to the rhinoplasty surgeon working with thin nasal skin. The thickness of the SSTE varies, being thickest over the radix and supratip area and thinnest at the rhinion. There are four layers of tissue that reside between the skin and osseocartilaginous framework: the superficial fatty panniculus, the fibromuscular layer, the deep fatty layer, and the perichondrium or periosteum. The fibromuscular layer contains the nasal superficial musculoaponeurotic system (SMAS), which is in continuity with facial SMAS, platysma, and galea. This layer provides structure and is flush to the underlying vascular supply of the SSTE. In the patient with thin nasal skin, extra care is taken to preserve the vascular supply of the SSTE by elevating a flap immediately superficial to the perichondrium.
The facial muscles exert dynamic forces on the nose that are often pronounced in patients with thin skin. The nasal muscles are innervated by the zygomatic branch of the facial nerve and have been divided into four groups: elevator, depressor, compressor, and minor dilator muscles. The elevator muscles, including the procerus, levator labii superioris alaeque nasi, and anomalous nasi, shorten the nose and dilate the nostrils. The depressor muscles, including the depressor septi and alar portion of the nasalis, lengthen the nose and dilate the nostrils. The compressor muscles, including the transverse portion of the nasalis and compressor narium minor, lengthen the nose and contract the nostrils. Last, the minor dilator muscle is the dilator naris anterior. These muscles have functional and aesthetic relevance to thin skin rhinoplasty, with their role in surgical treatment sometimes described as “dynamic rhinoplasty.” Understanding these muscle actions allows for improved control of dorsum–tip–labial relationships.
Types of Thin Skin
Naturally Thin Skin
In patients who have not undergone prior nasal surgery, the thickness of the supratip soft tissue is dictated by the density of sebaceous glands in the epithelium and the suppleness of the subcutaneous tissues. Patients with “thick skin,” discussed in detail in Chapter 27 in the text, usually have sebaceous skin with dense underlying soft tissues that obscure nasal framework and resist surgical refinement. Patients with naturally fine skin have the opposite problem—skin that reveals too much—and subtle imperfections will “shine through” the delicate veil of the thin nasal covering. In such cases, absence of the usual buffer of skin and soft tissue will often draw attention to the contours of the underlying cartilaginous and bony nasal anatomy in an unflattering manner. Thin skin may occur irrespective of age, gender, or ethnicity; however, the prototypical thin-skinned patient in the senior author’s practice is a young woman in her 30s, often of Nordic descent, with fair skin, blonde or red hair, and blue eyes (Fitzpatrick Type I or II).
Parchment Thin Skin
Thin skin is also seen in association with prior rhinoplasty. The prototypical patient in this setting is a female with medium to medium-thin facial skin who relates a history of progressive changes to the character of the skin subsequent to one or more prior rhinoplasties. Examination of the skin and its underlying soft tissue elements demonstrates atrophic changes in association with scarring. Actinic changes or talangiectasias are usually present, often over the rhinion, and there is poor elasticity to the nasal covering. This skin is sometimes described as “parchment thin skin,” a reflection of its fragile quality and its thin, almost translucent appearance.
In the previously operated nose, thin skin may be adherent to the underlying framework. As a result, the underlying cartilaginous and skeletal irregularities stand out in relief. Parchment preparation, which historically involved the stretching, scraping, and drying of skin under tension to create a stiff, translucent material, has much in common with the pathogenesis of iatrogenic thin skin in postrhinoplasty patients. Thinness of the SSTE—often unrecognized at time of original surgery—predisposes to development of this complication, but parchment thin skin usually indicates transection or injury of the nasal SMAS during dissection. This transgression permanently compromises skin quality and increases risk of alar retraction due to exaggerated scarification. Steroid injection compounds the problem.
Aging and Disease-Related Thin Skin
Last, normal aging and several disease entities cause thinning of the skin. These causes have an underlying physiology that differs from both innately thin nasal skin and from acquired parchment thin skin. Aging is associated with reduction of the skin’s strength, thickness, and elasticity. Actinic changes and solar damage also alter the characteristics of the skin and contribute to thinning and premature aging of the skin. Corticosteroid excess, as may occur with diseases of the adrenal cortex, pituitary neoplasms, and exogenous corticosteroid use are additional factors associated with thinning, weakening, and delayed healing of the skin. Ehlers-Danlos syndrome and osteogenesis imperfecta, which are associated with defective collagen synthesis, result in abnormally thin skin with decreased tensile strength, as part of their clinical behavior. While the techniques presented herein for thin skin are highly versatile, the dynamics of healing in aging and disease are beyond the scope of this chapter.
Philosophical Considerations Related to Thin Skin
Small Margin of Error
Identification of thin skin during the preoperative assessment is crucial in planning rhinoplasty so that the patient can be counseled appropriately and the surgical plan adapted to the special needs of thin skin. The potential margin for error is narrower in patients with thin nasal skin. While thin skin confers an excellent opportunity for achieving refinement of the nasal tip, subtle irregularities will be more difficult to conceal. Some patients have very strong or prominent cartilages whose entire cartilage outline is discernible.
The Shrink Wrap Effect
The “shrink wrap” effect that occurs after rhinoplasty is more profound in patients with thin skin. In contrast to thick skin, which limits the degree of resection that can be performed, thin skin allows for a greater degree of overall reduction and creation of a smaller nasal contour. On the other hand, such patients are at greater risk for disfigurement by the contractile forces of healing. During the postoperative course, patient with tight skin will notice that the nasal covering becomes even more constricted. The surgical plan must acknowledge that the toll of the “shrink wrap” effect may progress well beyond the first couple of postoperative years.
Implications of Thin Skin are Different for Each Third of the Nose
The healing process in patients with thin skin exerts characteristic effects on each portion of the nose. Over the bony pyramid, thin skin predisposes to palpable and sometimes visible osteotomy sites. Small spicules of bone, minor bony irregularities, or asymmetric bone regrowth are poorly concealed. The late narrowing of the nasal midvault seen with typical reductive rhinoplasty is accentuated in these patients. In addition, imprecise correction of the open roof deformity and other irregular contours become progressively more conspicuous as the skin seats down tightly over the framework. Thin skin in this area resists attempts by the surgeon to camouflage significant structural abnormalities with onlay grafts. The thin skin over the rhinion is most prone to alterations in color, texture, and tone. Prior to surgery, many patients have actinic changes; these patients need to be counseled regarding the risk for development of telangiectasias. The skin may become shiny as it becomes taut. The lower third of the nose is particularly prone to deforming forces of the healing SSTE.
The presence of thin skin has implications for all major aspects of rhinoplasty. Thin skin necessitates extra care in the elevation and protection of the SSTE; it requires specific strategies for structural correction and camouflage of the osseocartilaginous framework, and it calls for special measures for prevention and treatment of bossae and other contour irregularities. Skin color changes can be minimized or treated, and this will be discussed later in this chapter. Crushed cartilage may be combined with a variety of other soft tissue grafting materials. Certain adjunctive techniques are beneficial for fine tuning after thin skin rhinoplasty, although injection of either fillers or steroids is best performed conservatively or avoided altogether. Each of these technical points is covered in the discussion that follows.
Elevation and Protection of the Sste
In patients with thin nasal skin, it is important to elevate the SSTE in as thick a flap as possible. The plane of dissection is immediately superficial to the perichondrium over the upper and lower lateral cartilages and subperiosteal over the bony dorsum. If no bony dorsal surgery is required, elevation over the dorsum is avoided because such unnecessary dissection may provoke the unwanted shrink-wrap effect. Thick skin is comparatively forgiving of imprecise dissection, whereas failure to respect the vascular supply of the SSTE in the patient with thin skin results in excessive postoperative edema and a parchment-like character to the skin. Furthermore, transsection of the SMAS disrupts the anatomic barrier between the skin and structural framework, allowing adhesions to form between the framework and dermis. This impropriety can permanently compromise skin quality and also increases the risk of retraction and dimpling due to exaggerated scarification.
In cases of parchment thin skin, where the quality of the SSTE is compromised, we routinely place an implant that increases the thickness of the soft tissue between the skin envelope and the framework. When performing a secondary rhinoplasty, we will often harvest not only the conchal cartilage but also postauricular fibroconnective tissue, which is obtained from the conchal mastoid sulcus and over the mastoid process as shown in Figure 26-1 . This tissue is flattened in a tympanoplasty press, creating a pliable sheet of soft connective tissue that can be placed over the nasal framework. This graft can be heavily compressed, but it is kept hydrated to improve viability. In our hands, this technique not only thickens the SSTE but may actually improve the quality of the scarified SSTE, making it more supple and natural appearing. Temporalis fascia is also useful for this purpose. Perichondrium provides a nice soft tissue cushion and is readily available if one is harvesting a rib graft. Acellular dermal matrix is an alternative, but it does thin progressively over time, and in many cases virtually disappears.