- Email: [email protected]
Facial Skin Rejuvenation in the Asian Patient
381
FACIAL PLASTIC SURGERY CLINICS OF NORTH AMERICA Facial Plast Surg Clin N Am 15 (2007) 381–386
Facial Skin Rejuvenation in the Asian Patient Michael M. Kim, -
MD,
Patrick J. Byrne,
Anatomic distinctions Nonsurgical interventions Chemical peeling Other topical rejuvenation treatment
Over the last few decades, through political and economic reform, the countries of the Far East have transformed into powerful, export-based economies. Concomitant rises in disposable income, a greater cultural acceptance of aesthetic modification, and continued globalization have contributed to a surge in the interest in and performance of aesthetic enhancement procedures. Along with these developments, large-scale emigration of Asians to the United States has taken place, creating another distinct population complete with their own amalgamation of Eastern and Western ideals. Asia is the largest and most populous continent on Earth and comprises an incredible diversity of people. For the purposes of this article, the term ‘‘Asian’’ refers to the Mongoloid race of peoples from East Asian countries, such as China, Japan, and Korea, and excludes the white races that reside elsewhere on the continent. Eastern Asian countries alone comprise almost one quarter of the world’s population with approximately 1.5 billion people. This population is also prevalent in the United States, numbering 11 million people, or over 4% of the general population according to the 2000 US Census Bureau data. The largest numbers of Asians are concentrated on the coasts, with those cities situated on the Pacific Rim having the highest
-
MD, FACS*
Botulinum toxin type A (Botox) Photorejuvenation Summary References
proportions [1]. Despite narrowing the definition of Asian to this ethnically distinct group, there still remains considerable multiracial variation between and within these groups, each having its own specific geographic, historical, and cultural identities. Standards of beauty are diverse even within this narrowed group of people. In addition, comparing the concept of beauty between those residing in their native countries with those who were born or recently emigrated to the West may also be problematic [2]. The authors recognize the limitations of commenting on such diverse groups of people as one entity. Nonetheless, generalization of their anatomy, changes with aging, and specific desires with regards to rejuvenation are valuable when compared with white populations. Because of the relatively early rise and development of aesthetic enhancement procedures in the West, most of the literature has investigated these procedures in patients who identify themselves as white. Conversely, there is a paucity of literature concerning the Asian patient. Although anatomic and aging differences have been recognized for decades, only until recently have investigators recognized the need to tailor procedures, and sometimes avoid specific treatments, in Asian populations. This area of study is in its relative infancy,
Department of Otolaryngology - Head and Neck Surgery, Johns Hopkins University School of Medicine, 6th Floor Johns Hopkins Outpatient Center, 601 North Caroline Street, Baltimore, MD 21287, USA * Corresponding author. E-mail address: [email protected] (P.J. Byrne). 1064-7406/07/$ – see front matter ª 2007 Elsevier Inc. All rights reserved.
facialplastic.theclinics.com
doi:10.1016/j.fsc.2007.04.007
382
Kim & Byrne
and it is continuously evolving with the continued, surging demand for facial rejuvenation procedures among Asians.
Anatomic distinctions Although skin texture and pigmentation vary widely among Asians, in general Asian skin exhibits increased dermal thickness, collagen content, and melanin as compared with white skin. Increased dermal thickness may result in a decreased proclivity for fine facial rhytides, but also may be responsible for the higher incidence of hypertrophic scars and pigmented dermatoses with age [3]. A recent multicenter study by Nouveau-Richard and colleagues [4] compared skin aging between agematched women of Chinese and French descent. Their results confirmed that wrinkle onset in Asian women is delayed by approximately 10 years, whereas aging in Asians is more associated with the development of noncancerous pigmented lesions. Consequently, among Asians there tends to be less demand for procedures that address rhytides than those interventions that address pigmentation changes. Regardless of the differences between Asians and whites, the ultimate goal remains the same: to appear younger by removing or enhancing the respective stigmata of aging specific to their population. The facial plastic surgeon is equipped with a vast selection of rejuvenation procedures, many of which are nonablative in nature. Choosing interventions based on patient preferences and facial aging characteristics is important regardless of race. This article highlights the available facial skin rejuvenation techniques most suitable for the Asian face.
Nonsurgical interventions Myriad nonsurgical procedures have been developed to combat skin changes associated with aging. This is especially relevant in Asians, whose aging is often characterized by pigmentation changes that surgery cannot adequately address. In the West, more ablative procedures, such as dermabrasion, medium and deep chemical peels, and laser resurfacing, have been used with great success. In Asian skin, however, those procedures have resulted in posttreatment complications, such as persistent hyperemia, hyperpigmentation and hypopigmentation, and even hypertrophic scar formation [5]. Nonsurgical interventions in Asians tend toward nonablative or more superficial therapies that are associated with lowered incidence of complications.
Because of the inherent risk of pigmentary dyschromia in Asians after ablative treatments, only nonablative treatments should be used. The authors’ typical treatment progression starts with topical therapies following by spot peeling and intense pulsed light (IPL) treatments. By using a conservative treatment regimen, such complications as postinflammatory hyperpigmentation can be minimized while still providing excellent rejuvenation results.
Chemical peeling Chemical peeling involves the application of chemical exfoliants that remove layers of skin so that regeneration of skin with improved texture and pigmentation can occur. The various agents and techniques used each have distinctive characteristics and applications. In general, they fall within three groups based on their level of penetration into the epidermis and dermis: (1) superficial, (2) medium-depth, and (3) deep peels. Superficial peels are limited to the epidermis and induce epidermal regeneration alone. Medium-depth peels penetrate through the epidermis and into the papillary dermis, generating a dermal inflammatory response. Deep peels penetrate further into the reticular dermis, stimulating the production of new collagen and ground substance [6]. Asian skin typically exhibits Fitzpatrick [7] skin types III to V because of a relative increase in melanin as compared with whites (Table 1). As a consequence, Asians are less susceptible to photodamage and may not need the deeper peels that whites sometimes require. In addition, the use of medium-depth and deep peels in Asians is complicated by the higher incidence of postpeel pigmentary dyschromia [6]. The use of chemical peeling in Asians is generally limited to nonablative, superficial peels, and for the purposes of this
Table 1:
Fitzpatrick skin types
Type
Color
Tanning response
I
White
II
White
III
White
IV
Brown
V
Dark brown
VI
Black
Always burns, never tans Usually burns, tans with difficulty Sometimes mild burn, tan average Rarely burns, tans with ease Very rarely burns, tans very easily No burn, tans very easily
Facial Skin Rejuvenation in Asians
article, medium-depth and deep peels are not discussed in detail. The four major classes of superficial peels include (1) alpha-hydroxy acids, (2) beta-hydroxy acids, (3) trichloroacetic acid, and (4) Jessner’s solution (Box 1). Each type of peel has its own indications and safety profile, and it is incumbent on the practitioner to understand these characteristics. Furthermore, such factors as concentration, vehicle, amount used, and duration of contact can affect the depth of the peel. Treatment with superficial peels usually results in transient stinging and burning during the application and postpeel erythema for about 1 to 4 days, highlighting the fact that after superficial peels the patient experiences minimal downtime. Superficial peels by nature usually require multiple peeling sessions and often patients require treatment on a weekly basis for 6 to 8 weeks for maximal aesthetic benefit. Alpha-hydroxy acids are a class of peeling agents that include glycolic acid (derived from sugarcane); lactic acid (sour milk); malic acid (apples); citric acid (citrus fruits); and tartaric acid (grapes). The most commonly used alpha-hydroxy acid is glycolic acid, usually in a 30% to 70% solution or a 70% gel formulation. Increased concentrations yield deeper peels and the acid is often used in a buffered or partially neutralized form to increase its margin of safety [8]. After application, glycolic acid is neutralized by water or a bicarbonate solution. This agent has been shown to be particularly effective in those with acne with associated hyperpigmentation, a common finding in Asians [9]. The most commonly used beta-hydroxy acid is salicylic acid. Salicylic acid is derived from willow tree bark and is the active ingredient in many topical skin-care solutions for acne because of its exfoliant and comedolytic properties. It can be used alone in a 20% to 30% solution in ethanol or in conjunction with other peeling agents to enhance penetration and create a deeper peel. It can also be formulated for spot treatment of pigmented keratoses and has been shown to be effective and welltolerated in darker skin [10]. Trichloroacetic acid peels are agents used for both nonablative and ablative peels. Lower concentrations in the range of 10% to 25% are used in
Box 1:
Major types of superficial peels
Alpha-hydroxy acid Glycolic acid solution (30%–50%) or gel (70%) Beta-hydroxy acid Salicylic acid 20%–30% Trichloroacetic acid 10%–25% Jessner’s solution
Asians because they confer a superficial peel. Higher concentrations are avoided because of the potential risk of postinflammatory hyperpigmentation and even scarring. Trichloroacetic acid peels can also be used in a spot-peel fashion and are occasionally used in higher concentrations for this indication. Jessner’s solution is a combination of exfoliation agents including the aforementioned salicylic and lactic acids, and resorcinol, which is a phenolic skin-lightening agent. Multiple, proprietary formulations have been developed to take advantage of the synergistic keratolytic effects of combining multiple agents. These formulations are well-suited to the Asian patient because of their superficial nature and their ability to perform spot peels of common pigmented dermatoses, such as solar lentigines [8]. The Vitalize peel (SkinMedica, Carlsbad, California) is superficial combination peel similar to a Jessner’s peel and has been effectively used in the authors’ practice (Fig. 1). Despite the type of exfoliant used, superficial peeling agents are a diverse group of substances that share common traits: minimal patient downtime, the need for multiple applications, and often subtle results. Because of their safety profile andgeneral effectiveness, the application of chemical peels in Asians should be limited only to superficial peels.
Other topical rejuvenation treatment Despite the relatively gentle nature of superficial peels, pretreatment and posttreatment with adjunctive topical agents, such as sunscreen, 4% to 8% hydroquinone, and tretinoin are advocated to prevent pigmentary dyschromia and maximize the results of the peel [6]. One popular formulation is TriLuma (Galderma Laboratories, Fort Worth, Texas), which combines 4% hydroquinone, 0.05% tretinoin, and fluocinolone acetonide 0.01%, a topical steroid. Hydroquinone is a chemical compound that blocks tyrosinase from developing melanin precursors for the production of new pigment. Its use lies in its ability to block new pigment formation as the new epidermis heals after a chemical peel, leading to predictable and even chromatic results. Tretinoin, also known as all trans-retinoic acid or RetinA (OrthoNeutrogena, Titusville, New Jersey), is a topical compound used in the treatment of acne and photoaged skin. Although its mechanism of action is not clearly elucidated, recent research has shown that tretinoin is a ligand to retinoic acid receptors and activates a signal transduction cascade that has effects at the level of gene expression and not by secondary local effects as previously thought [11].
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Fig. 1. An example of a superficial (Vitalize) peel used on the brow of a patient with Fitzpatrick IV skin type. (A) Brow before treatment exhibiting numerous pigmentary dermatoses. (B) After 6 weeks of Vitalize peel treatments the brow has more even coloring and a more youthful appearance.
Often used in combination with chemical peels, topical formulations are frequently used as solitary treatment, and no doubt are integral to many of the proprietary formulations developed for the cosmoceutical industry.
Botulinum toxin type A (Botox) Although wrinkling occurs later in Asians, rhytides appear in the same predictable manner caused by the chronically repetitive action of the facial mimetic musculature under skin. The eradication of wrinkling around eyes, mouth, and forehead is still an important aesthetic consideration in Asians. To this end, many minimally invasive, nonsurgical treatments are available. Because of their effectiveness with few complications and negligible recovery time, injectable fillers and botulinum toxin type A (Botox; Allergan, Irvine, California) applications represent more than half of all aesthetic procedures performed, and this proportion is rapidly increasing [12]. Because injectable filling agents are covered elsewhere in this issue, the discussion is limited to botulinum toxin. Botulinum toxin from the bacterium Clostridium botulinum is produced in seven different serotypes (A–G), of which the A toxin is the most potent. Its mechanism of action is to block the release of the neurotransmitter acetylcholine at the neuromuscular junction, thereby causing paralysis of the affected muscle. Although human experience with botulinum toxin was initially as a naturally occurring poison, experimentation and careful investigations have allowed for numerous medical applications of the toxin. The first medical applications of botulinum toxin type A were for the treatment of blepharospasm and strabismus [13] and numerous other indications followed. It was not until the early 1990s that the facial aesthetic
applications as an effective treatment of fine facial wrinkling were first reported [14]. In one of the few studies investigating the effect of Botox on an Asian population, Ahn and colleagues [15] demonstrated no difference in longevity of treatment and the amount of toxin needed for effect despite the inherent differences in dermal thickness and collagen content seen in Asians. Deep age-related furrowing occurs in all populations, but specific anatomic and aging characteristics in Asians contribute to a high incidence of deep furrows. With the aging process, Asians typically accumulate a greater volume of fat in the midface relative to whites [3]. In addition, Asian facial skeletal structure exhibits prominent malar eminences and a relative lack of maxillary prominence contributing to a shallow midface. As such, ptosis of the malar fat pad onto a shallow midface results in especially prominent nasolabial mounds and deep nasolabial folds. These folds are not amenable to treatment by botulinum toxin A because they are not caused by hyperkinetic facial movements. Instead, nasolabial folds are addressed by rhytidectomy techniques or by other procedures that seek to either augment the furrow or reduce the volume of the adjacent soft tissue and fat.
Photorejuvenation Skin resurfacing through the use of ablative modalities, such as carbon dioxide (CO2), erbium, and yttrium-aluminum-garnet (YAG) lasers, has gained traction in the United States and Europe because they can be effective in the treatment of photoaging in lighter-skinned individuals [16]. Much like the example of deeper chemical peels, however, these laser resurfacing modalities have the potential to cause long-lasting pigmentary dyschromia in darkerskinned people [17], limiting their use for the
Facial Skin Rejuvenation in Asians
Asian patient with few exceptions. Chan and colleagues [18] studied the use of 532-nm wavelength neodymium (Nd):YAG lasers in Asians for the treatment of facial lentigines and found that postoperative hyperpigmentation was common and could occur regardless of the type of Nd:YAG laser used. Similarly, Q-switched ruby lasers caused a hyperpigmentation rate of 25% in a group of Chinese patients [19], and CO2 lasers have hyperpigmentation rates approaching 100% in dark-skinned individuals [20]. Because of the pigmentary dyschromia risk, researchers are actively investigating other less invasive and nonablative photorejuvenation techniques. One such nonablative technique is the use of IPL, which was presented by Bitter [21] in 2000. IPL is noncoherent broad-spectrum light used to stimulate the formation of collagen within the papillary dermis and to treat pigmented skin lesions and telangiectasias. Specific spectra of wavelengths are delivered and can be modified through the use of light-filtering mechanisms. Typically, IPL devices are set such that their light is absorbed by both melanin (absorbs from 250–1200 nm) and oxyhemoglobin (absorbs at 418, 542, and 577 nm) simultaneously [22]. This modality, much like that of superficial chemical peels, usually requires a series of treatments for maximal benefit. In 2001, Negishi and colleagues [5] demonstrated the use of IPL in an Asian cohort and showed it to be an effective, safe, and well-tolerated procedure with little to no postinflammatory hyperpigmentation or prolonged erythema. Because pigmented lesions and telangiectasias are common age-related skin changes in Asians, this modality may be ideally suited for this population.
Summary The primary differences in Asian skin to that of white skin are its increased dermal thickness, collagen content, and melanin content. Consequently, Asian skin tends to develop facial wrinkles later and fewer in number because photodamage is often less extensive. Instead, development of pigmented lesions, such as lentigines, is more prominent and is a common complaint of those Asians seeking facial skin rejuvenation. Another aspect of Asian skin is its propensity for hypertrophic scarring and postinflammatory hyperpigmentation after ablative treatments. The practitioner needs to be well-versed in the diverse array of conservative facial skin rejuvenation techniques that balance safety with effectiveness. By selecting nonablative treatments tailored toward the Asian patient, one can achieve superior aesthetic results.
The authors advocate a conservative facial skin rejuvenation algorithm in Asians. They typically begin with topical agents or IPL. Superficial or spot chemical peels may be used in selected cases. By using this conservative treatment strategy, one can simultaneously maximize the potential for excellent aesthetic results and minimize the risk of complications.
References [1] Populations and Projections Program PD, US Census Bureau. Projections of the resident population by race, Hispanic origin, and nativity: middle series, 2006–2010. Washington, DC: US Census Bureau; 2000. [2] Lam SM. Aesthetic facial surgery for the Asian male. Facial Plast Surg 2005;21(4):317–23. [3] McCurdy JA. Cosmetic surgery of the Asian face. In: Papel ID, editor. Facial plastic and reconstructive surgery. 2nd edition. New York: Thieme; 2002. p. 322–43. [4] Nouveau-Richard S, Yang Z, Mac-Mary S, et al. Skin ageing: a comparison between Chinese and European populations: a pilot study. J Dermatol Sci 2005;40(3):187–93. [5] Negishi K, Tezuka Y, Kushikata N, et al. Photorejuvenation for Asian skin by intense pulsed light. Dermatol Surg 2001;27(7):627–31 [discussion: 32]. [6] Monheit GD, Chastain MA. Chemical peels. Facial Plast Surg Clin North Am 2001;9(2): 239–55, viii. [7] Fitzpatrick TB. The validity and practicality of sun-reactive skin types I through VI. Arch Dermatol 1988;124(6):869–71. [8] Roberts WE. Chemical peeling in ethnic/dark skin. Dermatol Ther 2004;17(2):196–205. [9] Wang CM, Huang CL, Hu CT, et al. The effect of glycolic acid on the treatment of acne in Asian skin. Dermatol Surg 1997;23(1):23–9. [10] Grimes PE. The safety and efficacy of salicylic acid chemical peels in darker racial-ethnic groups. Dermatol Surg 1999;25(1):18–22. [11] Kang S. The mechanism of action of topical retinoids. Cutis 2005;75(2 Suppl):10–3 [discussion: 3]. [12] American Society for Aesthetic Plastic Surgery. 2005 Cosmetic Surgery National Database Statistics. Available at: http://www.surgery.org/download/ 2005stats.pdf. Accessed December 25, 2006. [13] Scott AB. Botulinum toxin injection into extraocular muscles as an alternative to strabismus surgery. Ophthalmology 1980;87(10):1044–9. [14] Blitzer A, Brin MF, Keen MS, et al. Botulinum toxin for the treatment of hyperfunctional lines of the face. Arch Otolaryngol Head Neck Surg 1993;119(9):1018–22. [15] Ahn KY, Park MY, Park DH, et al. Botulinum toxin A for the treatment of facial hyperkinetic wrinkle lines in Koreans. Plast Reconstr Surg 2000;105(2):778–84.
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[16] Goldberg DJ, Meine JG. A comparison of four frequency-doubled Nd:YAG (532 nm) laser systems for treatment of facial telangiectases. Dermatol Surg 1999;25(6):463–7. [17] Nanni CA, Alster TS. Complications of cutaneous laser surgery: a review. Dermatol Surg 1998;24(2):209–19. [18] Chan HH, Fung WK, Ying SY, et al. An in vivo trial comparing the use of different types of 532 nm Nd:YAG lasers in the treatment of facial lentigines in Oriental patients. Dermatol Surg 2000;26(8):743–9. [19] Murphy MJ, Huang MY. Q-switched ruby laser treatment of benign pigmented lesions in
Chinese skin. Ann Acad Med Singapore 1994; 23(1):60–6. [20] Nanni CA, Alster TS. Complications of carbon dioxide laser resurfacing: an evaluation of 500 patients. Dermatol Surg 1998;24(3): 315–20. [21] Bitter PH. Noninvasive rejuvenation of photodamaged skin using serial, full-face intense pulsed light treatments. Dermatol Surg 2000; 26(9):835–42 [discussion: 43]. [22] Weiss RA, Weiss MA, Beasley KL. Rejuvenation of photoaged skin: 5 years results with intense pulsed light of the face, neck, and chest. Dermatol Surg 2002;28(12):1115–9.
FACIAL PLASTIC SURGERY CLINICS OF NORTH AMERICA Facial Plast Surg Clin N Am 15 (2007) 381–386
Facial Skin Rejuvenation in the Asian Patient Michael M. Kim, -
MD,
Patrick J. Byrne,
Anatomic distinctions Nonsurgical interventions Chemical peeling Other topical rejuvenation treatment
Over the last few decades, through political and economic reform, the countries of the Far East have transformed into powerful, export-based economies. Concomitant rises in disposable income, a greater cultural acceptance of aesthetic modification, and continued globalization have contributed to a surge in the interest in and performance of aesthetic enhancement procedures. Along with these developments, large-scale emigration of Asians to the United States has taken place, creating another distinct population complete with their own amalgamation of Eastern and Western ideals. Asia is the largest and most populous continent on Earth and comprises an incredible diversity of people. For the purposes of this article, the term ‘‘Asian’’ refers to the Mongoloid race of peoples from East Asian countries, such as China, Japan, and Korea, and excludes the white races that reside elsewhere on the continent. Eastern Asian countries alone comprise almost one quarter of the world’s population with approximately 1.5 billion people. This population is also prevalent in the United States, numbering 11 million people, or over 4% of the general population according to the 2000 US Census Bureau data. The largest numbers of Asians are concentrated on the coasts, with those cities situated on the Pacific Rim having the highest
-
MD, FACS*
Botulinum toxin type A (Botox) Photorejuvenation Summary References
proportions [1]. Despite narrowing the definition of Asian to this ethnically distinct group, there still remains considerable multiracial variation between and within these groups, each having its own specific geographic, historical, and cultural identities. Standards of beauty are diverse even within this narrowed group of people. In addition, comparing the concept of beauty between those residing in their native countries with those who were born or recently emigrated to the West may also be problematic [2]. The authors recognize the limitations of commenting on such diverse groups of people as one entity. Nonetheless, generalization of their anatomy, changes with aging, and specific desires with regards to rejuvenation are valuable when compared with white populations. Because of the relatively early rise and development of aesthetic enhancement procedures in the West, most of the literature has investigated these procedures in patients who identify themselves as white. Conversely, there is a paucity of literature concerning the Asian patient. Although anatomic and aging differences have been recognized for decades, only until recently have investigators recognized the need to tailor procedures, and sometimes avoid specific treatments, in Asian populations. This area of study is in its relative infancy,
Department of Otolaryngology - Head and Neck Surgery, Johns Hopkins University School of Medicine, 6th Floor Johns Hopkins Outpatient Center, 601 North Caroline Street, Baltimore, MD 21287, USA * Corresponding author. E-mail address: [email protected] (P.J. Byrne). 1064-7406/07/$ – see front matter ª 2007 Elsevier Inc. All rights reserved.
facialplastic.theclinics.com
doi:10.1016/j.fsc.2007.04.007
382
Kim & Byrne
and it is continuously evolving with the continued, surging demand for facial rejuvenation procedures among Asians.
Anatomic distinctions Although skin texture and pigmentation vary widely among Asians, in general Asian skin exhibits increased dermal thickness, collagen content, and melanin as compared with white skin. Increased dermal thickness may result in a decreased proclivity for fine facial rhytides, but also may be responsible for the higher incidence of hypertrophic scars and pigmented dermatoses with age [3]. A recent multicenter study by Nouveau-Richard and colleagues [4] compared skin aging between agematched women of Chinese and French descent. Their results confirmed that wrinkle onset in Asian women is delayed by approximately 10 years, whereas aging in Asians is more associated with the development of noncancerous pigmented lesions. Consequently, among Asians there tends to be less demand for procedures that address rhytides than those interventions that address pigmentation changes. Regardless of the differences between Asians and whites, the ultimate goal remains the same: to appear younger by removing or enhancing the respective stigmata of aging specific to their population. The facial plastic surgeon is equipped with a vast selection of rejuvenation procedures, many of which are nonablative in nature. Choosing interventions based on patient preferences and facial aging characteristics is important regardless of race. This article highlights the available facial skin rejuvenation techniques most suitable for the Asian face.
Nonsurgical interventions Myriad nonsurgical procedures have been developed to combat skin changes associated with aging. This is especially relevant in Asians, whose aging is often characterized by pigmentation changes that surgery cannot adequately address. In the West, more ablative procedures, such as dermabrasion, medium and deep chemical peels, and laser resurfacing, have been used with great success. In Asian skin, however, those procedures have resulted in posttreatment complications, such as persistent hyperemia, hyperpigmentation and hypopigmentation, and even hypertrophic scar formation [5]. Nonsurgical interventions in Asians tend toward nonablative or more superficial therapies that are associated with lowered incidence of complications.
Because of the inherent risk of pigmentary dyschromia in Asians after ablative treatments, only nonablative treatments should be used. The authors’ typical treatment progression starts with topical therapies following by spot peeling and intense pulsed light (IPL) treatments. By using a conservative treatment regimen, such complications as postinflammatory hyperpigmentation can be minimized while still providing excellent rejuvenation results.
Chemical peeling Chemical peeling involves the application of chemical exfoliants that remove layers of skin so that regeneration of skin with improved texture and pigmentation can occur. The various agents and techniques used each have distinctive characteristics and applications. In general, they fall within three groups based on their level of penetration into the epidermis and dermis: (1) superficial, (2) medium-depth, and (3) deep peels. Superficial peels are limited to the epidermis and induce epidermal regeneration alone. Medium-depth peels penetrate through the epidermis and into the papillary dermis, generating a dermal inflammatory response. Deep peels penetrate further into the reticular dermis, stimulating the production of new collagen and ground substance [6]. Asian skin typically exhibits Fitzpatrick [7] skin types III to V because of a relative increase in melanin as compared with whites (Table 1). As a consequence, Asians are less susceptible to photodamage and may not need the deeper peels that whites sometimes require. In addition, the use of medium-depth and deep peels in Asians is complicated by the higher incidence of postpeel pigmentary dyschromia [6]. The use of chemical peeling in Asians is generally limited to nonablative, superficial peels, and for the purposes of this
Table 1:
Fitzpatrick skin types
Type
Color
Tanning response
I
White
II
White
III
White
IV
Brown
V
Dark brown
VI
Black
Always burns, never tans Usually burns, tans with difficulty Sometimes mild burn, tan average Rarely burns, tans with ease Very rarely burns, tans very easily No burn, tans very easily
Facial Skin Rejuvenation in Asians
article, medium-depth and deep peels are not discussed in detail. The four major classes of superficial peels include (1) alpha-hydroxy acids, (2) beta-hydroxy acids, (3) trichloroacetic acid, and (4) Jessner’s solution (Box 1). Each type of peel has its own indications and safety profile, and it is incumbent on the practitioner to understand these characteristics. Furthermore, such factors as concentration, vehicle, amount used, and duration of contact can affect the depth of the peel. Treatment with superficial peels usually results in transient stinging and burning during the application and postpeel erythema for about 1 to 4 days, highlighting the fact that after superficial peels the patient experiences minimal downtime. Superficial peels by nature usually require multiple peeling sessions and often patients require treatment on a weekly basis for 6 to 8 weeks for maximal aesthetic benefit. Alpha-hydroxy acids are a class of peeling agents that include glycolic acid (derived from sugarcane); lactic acid (sour milk); malic acid (apples); citric acid (citrus fruits); and tartaric acid (grapes). The most commonly used alpha-hydroxy acid is glycolic acid, usually in a 30% to 70% solution or a 70% gel formulation. Increased concentrations yield deeper peels and the acid is often used in a buffered or partially neutralized form to increase its margin of safety [8]. After application, glycolic acid is neutralized by water or a bicarbonate solution. This agent has been shown to be particularly effective in those with acne with associated hyperpigmentation, a common finding in Asians [9]. The most commonly used beta-hydroxy acid is salicylic acid. Salicylic acid is derived from willow tree bark and is the active ingredient in many topical skin-care solutions for acne because of its exfoliant and comedolytic properties. It can be used alone in a 20% to 30% solution in ethanol or in conjunction with other peeling agents to enhance penetration and create a deeper peel. It can also be formulated for spot treatment of pigmented keratoses and has been shown to be effective and welltolerated in darker skin [10]. Trichloroacetic acid peels are agents used for both nonablative and ablative peels. Lower concentrations in the range of 10% to 25% are used in
Box 1:
Major types of superficial peels
Alpha-hydroxy acid Glycolic acid solution (30%–50%) or gel (70%) Beta-hydroxy acid Salicylic acid 20%–30% Trichloroacetic acid 10%–25% Jessner’s solution
Asians because they confer a superficial peel. Higher concentrations are avoided because of the potential risk of postinflammatory hyperpigmentation and even scarring. Trichloroacetic acid peels can also be used in a spot-peel fashion and are occasionally used in higher concentrations for this indication. Jessner’s solution is a combination of exfoliation agents including the aforementioned salicylic and lactic acids, and resorcinol, which is a phenolic skin-lightening agent. Multiple, proprietary formulations have been developed to take advantage of the synergistic keratolytic effects of combining multiple agents. These formulations are well-suited to the Asian patient because of their superficial nature and their ability to perform spot peels of common pigmented dermatoses, such as solar lentigines [8]. The Vitalize peel (SkinMedica, Carlsbad, California) is superficial combination peel similar to a Jessner’s peel and has been effectively used in the authors’ practice (Fig. 1). Despite the type of exfoliant used, superficial peeling agents are a diverse group of substances that share common traits: minimal patient downtime, the need for multiple applications, and often subtle results. Because of their safety profile andgeneral effectiveness, the application of chemical peels in Asians should be limited only to superficial peels.
Other topical rejuvenation treatment Despite the relatively gentle nature of superficial peels, pretreatment and posttreatment with adjunctive topical agents, such as sunscreen, 4% to 8% hydroquinone, and tretinoin are advocated to prevent pigmentary dyschromia and maximize the results of the peel [6]. One popular formulation is TriLuma (Galderma Laboratories, Fort Worth, Texas), which combines 4% hydroquinone, 0.05% tretinoin, and fluocinolone acetonide 0.01%, a topical steroid. Hydroquinone is a chemical compound that blocks tyrosinase from developing melanin precursors for the production of new pigment. Its use lies in its ability to block new pigment formation as the new epidermis heals after a chemical peel, leading to predictable and even chromatic results. Tretinoin, also known as all trans-retinoic acid or RetinA (OrthoNeutrogena, Titusville, New Jersey), is a topical compound used in the treatment of acne and photoaged skin. Although its mechanism of action is not clearly elucidated, recent research has shown that tretinoin is a ligand to retinoic acid receptors and activates a signal transduction cascade that has effects at the level of gene expression and not by secondary local effects as previously thought [11].
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Fig. 1. An example of a superficial (Vitalize) peel used on the brow of a patient with Fitzpatrick IV skin type. (A) Brow before treatment exhibiting numerous pigmentary dermatoses. (B) After 6 weeks of Vitalize peel treatments the brow has more even coloring and a more youthful appearance.
Often used in combination with chemical peels, topical formulations are frequently used as solitary treatment, and no doubt are integral to many of the proprietary formulations developed for the cosmoceutical industry.
Botulinum toxin type A (Botox) Although wrinkling occurs later in Asians, rhytides appear in the same predictable manner caused by the chronically repetitive action of the facial mimetic musculature under skin. The eradication of wrinkling around eyes, mouth, and forehead is still an important aesthetic consideration in Asians. To this end, many minimally invasive, nonsurgical treatments are available. Because of their effectiveness with few complications and negligible recovery time, injectable fillers and botulinum toxin type A (Botox; Allergan, Irvine, California) applications represent more than half of all aesthetic procedures performed, and this proportion is rapidly increasing [12]. Because injectable filling agents are covered elsewhere in this issue, the discussion is limited to botulinum toxin. Botulinum toxin from the bacterium Clostridium botulinum is produced in seven different serotypes (A–G), of which the A toxin is the most potent. Its mechanism of action is to block the release of the neurotransmitter acetylcholine at the neuromuscular junction, thereby causing paralysis of the affected muscle. Although human experience with botulinum toxin was initially as a naturally occurring poison, experimentation and careful investigations have allowed for numerous medical applications of the toxin. The first medical applications of botulinum toxin type A were for the treatment of blepharospasm and strabismus [13] and numerous other indications followed. It was not until the early 1990s that the facial aesthetic
applications as an effective treatment of fine facial wrinkling were first reported [14]. In one of the few studies investigating the effect of Botox on an Asian population, Ahn and colleagues [15] demonstrated no difference in longevity of treatment and the amount of toxin needed for effect despite the inherent differences in dermal thickness and collagen content seen in Asians. Deep age-related furrowing occurs in all populations, but specific anatomic and aging characteristics in Asians contribute to a high incidence of deep furrows. With the aging process, Asians typically accumulate a greater volume of fat in the midface relative to whites [3]. In addition, Asian facial skeletal structure exhibits prominent malar eminences and a relative lack of maxillary prominence contributing to a shallow midface. As such, ptosis of the malar fat pad onto a shallow midface results in especially prominent nasolabial mounds and deep nasolabial folds. These folds are not amenable to treatment by botulinum toxin A because they are not caused by hyperkinetic facial movements. Instead, nasolabial folds are addressed by rhytidectomy techniques or by other procedures that seek to either augment the furrow or reduce the volume of the adjacent soft tissue and fat.
Photorejuvenation Skin resurfacing through the use of ablative modalities, such as carbon dioxide (CO2), erbium, and yttrium-aluminum-garnet (YAG) lasers, has gained traction in the United States and Europe because they can be effective in the treatment of photoaging in lighter-skinned individuals [16]. Much like the example of deeper chemical peels, however, these laser resurfacing modalities have the potential to cause long-lasting pigmentary dyschromia in darkerskinned people [17], limiting their use for the
Facial Skin Rejuvenation in Asians
Asian patient with few exceptions. Chan and colleagues [18] studied the use of 532-nm wavelength neodymium (Nd):YAG lasers in Asians for the treatment of facial lentigines and found that postoperative hyperpigmentation was common and could occur regardless of the type of Nd:YAG laser used. Similarly, Q-switched ruby lasers caused a hyperpigmentation rate of 25% in a group of Chinese patients [19], and CO2 lasers have hyperpigmentation rates approaching 100% in dark-skinned individuals [20]. Because of the pigmentary dyschromia risk, researchers are actively investigating other less invasive and nonablative photorejuvenation techniques. One such nonablative technique is the use of IPL, which was presented by Bitter [21] in 2000. IPL is noncoherent broad-spectrum light used to stimulate the formation of collagen within the papillary dermis and to treat pigmented skin lesions and telangiectasias. Specific spectra of wavelengths are delivered and can be modified through the use of light-filtering mechanisms. Typically, IPL devices are set such that their light is absorbed by both melanin (absorbs from 250–1200 nm) and oxyhemoglobin (absorbs at 418, 542, and 577 nm) simultaneously [22]. This modality, much like that of superficial chemical peels, usually requires a series of treatments for maximal benefit. In 2001, Negishi and colleagues [5] demonstrated the use of IPL in an Asian cohort and showed it to be an effective, safe, and well-tolerated procedure with little to no postinflammatory hyperpigmentation or prolonged erythema. Because pigmented lesions and telangiectasias are common age-related skin changes in Asians, this modality may be ideally suited for this population.
Summary The primary differences in Asian skin to that of white skin are its increased dermal thickness, collagen content, and melanin content. Consequently, Asian skin tends to develop facial wrinkles later and fewer in number because photodamage is often less extensive. Instead, development of pigmented lesions, such as lentigines, is more prominent and is a common complaint of those Asians seeking facial skin rejuvenation. Another aspect of Asian skin is its propensity for hypertrophic scarring and postinflammatory hyperpigmentation after ablative treatments. The practitioner needs to be well-versed in the diverse array of conservative facial skin rejuvenation techniques that balance safety with effectiveness. By selecting nonablative treatments tailored toward the Asian patient, one can achieve superior aesthetic results.
The authors advocate a conservative facial skin rejuvenation algorithm in Asians. They typically begin with topical agents or IPL. Superficial or spot chemical peels may be used in selected cases. By using this conservative treatment strategy, one can simultaneously maximize the potential for excellent aesthetic results and minimize the risk of complications.
References [1] Populations and Projections Program PD, US Census Bureau. Projections of the resident population by race, Hispanic origin, and nativity: middle series, 2006–2010. Washington, DC: US Census Bureau; 2000. [2] Lam SM. Aesthetic facial surgery for the Asian male. Facial Plast Surg 2005;21(4):317–23. [3] McCurdy JA. Cosmetic surgery of the Asian face. In: Papel ID, editor. Facial plastic and reconstructive surgery. 2nd edition. New York: Thieme; 2002. p. 322–43. [4] Nouveau-Richard S, Yang Z, Mac-Mary S, et al. Skin ageing: a comparison between Chinese and European populations: a pilot study. J Dermatol Sci 2005;40(3):187–93. [5] Negishi K, Tezuka Y, Kushikata N, et al. Photorejuvenation for Asian skin by intense pulsed light. Dermatol Surg 2001;27(7):627–31 [discussion: 32]. [6] Monheit GD, Chastain MA. Chemical peels. Facial Plast Surg Clin North Am 2001;9(2): 239–55, viii. [7] Fitzpatrick TB. The validity and practicality of sun-reactive skin types I through VI. Arch Dermatol 1988;124(6):869–71. [8] Roberts WE. Chemical peeling in ethnic/dark skin. Dermatol Ther 2004;17(2):196–205. [9] Wang CM, Huang CL, Hu CT, et al. The effect of glycolic acid on the treatment of acne in Asian skin. Dermatol Surg 1997;23(1):23–9. [10] Grimes PE. The safety and efficacy of salicylic acid chemical peels in darker racial-ethnic groups. Dermatol Surg 1999;25(1):18–22. [11] Kang S. The mechanism of action of topical retinoids. Cutis 2005;75(2 Suppl):10–3 [discussion: 3]. [12] American Society for Aesthetic Plastic Surgery. 2005 Cosmetic Surgery National Database Statistics. Available at: http://www.surgery.org/download/ 2005stats.pdf. Accessed December 25, 2006. [13] Scott AB. Botulinum toxin injection into extraocular muscles as an alternative to strabismus surgery. Ophthalmology 1980;87(10):1044–9. [14] Blitzer A, Brin MF, Keen MS, et al. Botulinum toxin for the treatment of hyperfunctional lines of the face. Arch Otolaryngol Head Neck Surg 1993;119(9):1018–22. [15] Ahn KY, Park MY, Park DH, et al. Botulinum toxin A for the treatment of facial hyperkinetic wrinkle lines in Koreans. Plast Reconstr Surg 2000;105(2):778–84.
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[16] Goldberg DJ, Meine JG. A comparison of four frequency-doubled Nd:YAG (532 nm) laser systems for treatment of facial telangiectases. Dermatol Surg 1999;25(6):463–7. [17] Nanni CA, Alster TS. Complications of cutaneous laser surgery: a review. Dermatol Surg 1998;24(2):209–19. [18] Chan HH, Fung WK, Ying SY, et al. An in vivo trial comparing the use of different types of 532 nm Nd:YAG lasers in the treatment of facial lentigines in Oriental patients. Dermatol Surg 2000;26(8):743–9. [19] Murphy MJ, Huang MY. Q-switched ruby laser treatment of benign pigmented lesions in
Chinese skin. Ann Acad Med Singapore 1994; 23(1):60–6. [20] Nanni CA, Alster TS. Complications of carbon dioxide laser resurfacing: an evaluation of 500 patients. Dermatol Surg 1998;24(3): 315–20. [21] Bitter PH. Noninvasive rejuvenation of photodamaged skin using serial, full-face intense pulsed light treatments. Dermatol Surg 2000; 26(9):835–42 [discussion: 43]. [22] Weiss RA, Weiss MA, Beasley KL. Rejuvenation of photoaged skin: 5 years results with intense pulsed light of the face, neck, and chest. Dermatol Surg 2002;28(12):1115–9.