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Abstract and IntroductionAbstractThe Asian patient with Fitzpatrick skin types III-V is rarely highlighted in publications on cutaneous disorders or cutaneouslaser surgery. However, with changing demographics, Asians will become an increasingly important group in this context.Although high melanin content confers better photoprotection, photodamage in the form of pigmentary disorders is common.Melasma, freckles, and lentigines are the epidermal disorders commonly seen, whilst nevus of Ota and acquired bilateralnevus of Ota-like macules are common dermal pigmentary disorders. Post-inflammatory hyperpigmentation (PIH) occurringafter cutaneous injury remains a hallmark of skin of color. With increasing use of lasers and light sources in Asians,prevention and management of PIH is of great research interest. Bleaching agents, chemical peels, intense pulsed light(IPL) treatments, and fractional skin resurfacing have all been used with some success for the management of melasma.Q-switched (QS) lasers are effective for the management of epidermal pigmentation but are associated with a high risk ofPIH. Long-pulsed neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers and IPL sources pose less of a PIH risk butrequire a greater number of treatment sessions. Dermal pigmentary disorders are better targeted by QS ruby, QSalexandrite, and QS 1064-nm Nd:YAG lasers, but hyper- and hypopigmentation may occur. Non-ablative skin rejuvenationusing a combination approach with different lasers and light sources in conjunction with cooling devices allows different skinchromophores to be targeted and optimal results to be achieved, even in skin of color. Deep-tissue heating usingradiofrequency and infra-red light sources affects the deep dermis and achieves enhanced skin tightening, resulting ineyebrow elevation, rhytide reduction, and contouring of the lower face and jawline. For management of severe degrees ofphotoaging, fractional resurfacing is useful for wrinkle and pigment reduction, as well as acne scarring.

Acne, which is common in Asians, can be treated with topical and oral antibacterials, hormonal treatments, and isotretinoin.Infra-red diode lasers used with a low-fluence, multiple-pass approach have also been shown to be effective with fewcomplications. Fractional skin resurfacing is very useful for improving the appearance of acne scarring. Hypertrophic andkeloid scarring, another common condition seen in Asians, can be treated with the combined used of intralesionaltriamcinolone and fluorouracil, followed by pulsed-dye laser. Esthetic enhancement procedures such as botulinum toxin typeA and fillers are becoming increasingly popular. These are effective for rhytide improvement and facial or body contouring.We highlight the differences between Asian skin and other skin types and review conditions common in skin of color togetherwith treatment strategies.

IntroductionPopulation demographics have evolved in the 21st century such that over half the world's population is Asian.[1] The USCensus 2000 reported that 4.2% of the US population was of Asian origin.[2] Furthermore, this fastest growing group in theUS population is projected to double in size by 2050.[3] The term Asian refers to people having origins from the Far East,southeast Asia, or the Indian subcontinent.[2] They are a diverse group with various skin phototypes ranging from Fitzpatricktype III to V in the Chinese and Japanese to type IV and V in Indians and Pakistanis. We review cutaneous disorders thatare common or particular to skin of color (with particular emphasis on Asian patients) and discuss the management of theseconditions.

1. Photoaging in AsiansNinety-five percent of the visible signs of aging are caused by sun exposure, which begins in infancy and continuesthroughout life. Other intrinsic factors such as gravity and pollution also contribute to the cutaneous aging process.[4]

Skin of color is differentiated by the amount and epidermal distribution of melanin. Szabo[5] established that although there

The Asian Dermatologic Patient: Review ofCommon Pigmentary Disorders andCutaneous DiseasesStephanie G.Y. Ho, Henry H.L. ChanAm J Clin Dermatol. 2009;10(3):153-168.

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are no racial differences in melanocyte density, darker skin has larger melanocytes producing more melanin and themelanosomes are distributed individually in keratinocytes. The increased melanin and more dispersed melanosomes appearto absorb and deflect UV light more efficiently, conferring significant photoprotection to skin of color.[6] Tadokoro et al.[7]confirmed this by showing a close inverse correlation between melanin content in the skin and the amount of DNA damageresulting from a given dose of UV radiation.

Despite this, Kotrajaras and Kligman[8] reported that significant photodamage in the form of epidermal atypia and atrophy,dermal collagen and elastin damage, and pigmentary disorders can occur in skin of color. Other investigators have similarlyobserved that pigmentary changes occur with a greater incidence than skin wrinkling in Asians.[9,10] Chung[11] more recentlyfound both pigmentary changes and wrinkling to be major features of photoaging in Asians. However, moderate-to-severewrinkling becomes apparent only at about 50 years of age, which is a decade or two later than in age-matchedCaucasians.[4]

Other cutaneous manifestations of aging ethnic skin include the development of benign cutaneous growths such asdermatosis papulosa nigra, seborrheic keratoses, and the development of solar lentigines.[4,11]

2. Disorders of Pigmentation2.1 Post-Inflammatory HyperpigmentationPost-inflammatory hyperpigmentation (PIH) is a common pigmentary disorder in melanin-rich Asian skin.[12] PIH can beconsidered the default pathophysiologic response to cutaneous injury in such individuals. Several factors contribute to thedevelopment of PIH, including increased melanocytic activities, dermal melanophages, and hemosiderin depositionsecondary to hemorrhage. The severity of PIH is related to the degree of inflammation and extent of disruption of theepidermo-dermal junction. It may be caused by endogenous inflammatory skin disorders or iatrogenic sources such aslasers.[13] The high epidermal melanin content in Asian skin may act as a competing chromophobe for vascular and pigmentlasers, interfering with the absorption of laser energy that is intended for another target. With increasing use of lasers andlight sources in Asians, prevention and management of PIH is becoming increasingly important.[14] This will be discussed inmore detail in subsequent sections.

2.2 MelasmaMelasma is an acquired symmetric hypermelanosis involving sun-exposed areas commonly seen in Asian middle-agedwomen. Genetics, UV radiation, pregnancy, hormonal therapies, and other phototoxic drugs are all thought to be contributingetiologic factors and melasma remains a difficult condition to treat. Melasma was formerly classified histopathologically asepidermal, dermal, or mixed type depending on the location of the pigment.[15] However, Kang et al.,[16] in a histopathologicstudy of 56 Korean patients with melasma, suggested that there is no true dermal type and the dermal melanophages seenin 'dermal-type melasma' may be due to undiagnosed acquired bilateral nevus of Ota-like macules or Hori's macules.

In a study comparing the histopathologic features of melasma with those of normal skin using several differentimmunohistochemical stains, Kang et al.[16] reported that melasma skin had more melanin in the whole epidermis whereasmelanin is confined to the basal layer in normal skin. Increased numbers of melanocytes and widely dispersed melanosomesin keratinocytes are also found in melasma lesions. These investigators proposed that increased activity of melanogenicenzymes results in hyperactive melanocytes with increased synthesis and transfer of melanosomes, and decreaseddegradation in keratinocytes. Sublethal laser damage to these labile melanocytes can increase the production of melaninand lead to PIH.[16] This may explain why previous studies using a 510-nm pigmented lesion dye laser[17] and a Q-switched(QS) ruby laser[18] for the management of melasma led to little improvement and worsening of pigmentation in some cases.Recent studies have also indicated that intense pulsed light (IPL) can lead to manifestation of previously subclinicalmelasma; for this reason, Wood's light examination or UV photography prior to IPL treatment of Asian skin is recommended.[19,20]Use of bleaching agents and sunscreens for at least 6 weeks, and preferably for 3 months, prior to any laser or light therapycan help suppress the function of these hyperactive melanocytes and reduce the risk of PIH.[14] Even with such precautions,a recent study in Taipei[20] that compared topical bleaching treatment only with bleaching plus IPL treatment for melasmareported two cases of PIH in the IPL-treated group despite prolonged use of bleaching agents and sunscreens prior totreatment.


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Combinations of hydroquinone with topical corticosteroids and tretinoin have been reported to be effective as first-linetreatment of melasma.[21,22] The limitations of topical treatment include the longer time required for effectiveness to becomeapparent and patient compliance. Glycolic acid, salicylic acid, and trichloroacetic acid peels are also useful adjuncts totopical treatments in the management of melasma in Asians.[23-25]

Wang et al.[20] in Taipei showed that patients with melasma in the IPL-treated group achieved a significant improvement of39.8% compared with 11.6% in the control group after four sessions of IPL and topical treatment. However, partialrepigmentation was noted 24 weeks later, suggesting the need for repeated treatments for maintenance. These investigatorssuggested use of the lowest fluence to achieve minimal erythema, a recommendation supported by the findings of Negishi etal.[19] This avoids excessive thermal injury to labile melanocytes and reduces the risk of PIH.

Ablative lasers such as carbon dioxide lasers and QS alexandrite lasers have been used with some success in the treatmentof melasma.[26-28] These lasers are thought to prevent the clonal expansion of hyperactive melanocytes located in theepidermal basal layer. In addition, ablative lasers may increase the topical absorption of bleaching agents in patients withimpaired epidermal barrier function. However, the significant downtime and adverse effects associated with the use ofablative lasers has made them unpopular.

Fractional skin resurfacing is a recent development in the management of melasma (figure 1). This involves the use of a1540-nm laser that creates microscopic zones of thermal injury that are surrounded by normal skin. As the areas of thermalinjury are very small, lateral migration of keratinocytes to them occurs rapidly, leading to re-epithelialization of the epidermiswithin 24 hours.[14] Rokhsar and Fitzpatrick[29] conducted a small study that evaluated use of fractional resurfacing (Fraxel,Reliant Technologies, Mountain View, CA, USA) in the treatment of melasma. In their ten subjects, using 6-12 mJ at2000-3500 microthermal treatment zone (MTZ)/cm2 as treatment parameters, 60% reported 75-100% clearing of melasma,30% reported

Figure 1.

Treatment of melasma with fractional skin resurfacing: (a) pre-treatment; (b) post-treatment.

2.3 Freckles and LentiginesFreckles and lentigines are common benign pigmented lesions seen in Asians. As the cultural trend in Asians movestowards fair porcelain skin, these pigmented lesions can often present in dermatology outpatients as a cosmetic concern.

Freckles or ephelides occur in adolescence and are relatively uniform in distribution, size, and color. Histopathologically,epidermal hypermelanosis without an increase in melanocyte number is seen. Lentigines increase in number and prevalencewith age. They tend to vary in size and color and are non-uniformly distributed. Histologically, the number of melanocytesand epidermal hypermelanosis are increased and the epidermal rete ridges are elongated.[30]

Anderson et al.[31] were the first to demonstrate the effectiveness of QS neodymium-doped yttrium aluminum garnet(Nd:YAG) laser in the treatment of cutaneous pigmentation. However, studies using QS Nd:YAG, QS ruby, and QSalexandrite lasers for pigmented lesions in Asians have reported a PIH risk of around 25%.[30,32,33] Chan et al.[33] comparedthe use of different types of 532-nm Nd:YAG lasers in the treatment of facial lentigines in Chinese patients and found similareffectiveness for the QS Nd:YAG and long-pulsed Nd:YAG. However, there was a higher risk of post-operativehyperpigmentation with the QS device. It has been suggested that unlike the long-pulsed laser that causes tissue destructionpurely by photothermolysis, the QS Nd:YAG laser, with its high-energy nanosecond radiation, exhibits both photothermal andphotomechanical effects. The undesirable photomechanical effect induces damage to surrounding oxyhemoglobin as well astarget melanin, resulting in inflammation of superficial vessels, altered activity of melanocytes, and subsequent PIH.[34]Results from other studies also support the theory that long-pulsed devices are more suitable for Asian skin in reducing therisk of PIH.[30,35]

IPL sources emit a broad band of visible light from a non-coherent filtered flashlamp and produce photothermal effectsonly.[36] There have been several studies confirming the effectiveness of IPL in the management of epidermal pigmentationin Asians. Negishi et al.[35,37] conducted two studies that evaluated photorejuvenation using IPL. Results from the first studyinvolving 97 Asian patients (cut-off filter 550 nm, 28-32 J/cm2, double-pulse mode of 2.5-4.0/4.0-5.0 msec, delay time20.0/40.0 msec) showed that >90% of patients reported a reduction in pigmentation after three to six treatments at intervalsof 2-3 weeks.[35] The second study used IPL with an integrated contact cooling system (cut-off filter 560 nm, 23-27 J/cm2,double-pulse mode of 2.8-3.2/6.0 msec, delay time 20.0/40.0 msec) and, in this study, 80% of the 73 patients evaluated hada significant reduction in pigmentation after three to five treatments at intervals of 3-4 weeks.[37] Kawada et al.[38] evaluated60 patients with solar lentigines and freckles and reported more than 50% improvement in 68% of these patients followingthree to five IPL treatments at intervals of 2-3 weeks (cut-off filter 560 nm, 20-24 J/cm2, 2.6-5.0 msec pulse duration indouble or triple pulses, delay time 20 msec). Freckles responded better than lentigines. Interestingly, post-operative PIH wasnot seen in any of these studies, highlighting the advantage of IPL as a treatment choice for photorejuvenation in Asianpatients.

A treatment algorithm relating to use of lasers and IPL sources for the treatment of acquired pigmentary lesions in Asianshas been put forward by Chan[36] to help physicians weigh up issues such as cost effectiveness, clinical outcome, andadverse events such as PIH. This author suggests IPL for patients who demand a low risk of PIH and who are amenable tohaving several treatment sessions. A median approach using long-pulsed Nd:YAG may be considered if a faster outcome isdesired. An aggressive approach using QS lasers requires only one to two sessions, which make this approach the mosttime- and cost-effective approach; however, it also carries the highest risk of PIH and necessitates a downtime period of 1week.

Other means of reducing PIH in Asians include diascopy during laser therapy to compress and empty dermal vessels inorder to reduce the risk of dermal vascular damage and hemosiderin deposition. Kono et al.[39] recently compared theefficacy and complications seen with use of the QS ruby laser and the 595-nm-long pulsed dye laser (PDL) delivered with acompression method in the treatment of lentigines. The efficacy was similar in both groups but there was a much lower riskof PIH in the group treated with the compression technique. Using a laser or light source with a shorter wavelength (350-500


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nm) confines the thermal injury to the epidermal layer and is another means of reducing the risk of PIH.[4]

2.4 Nevus of OtaNevus of Ota is a dermal melanocytic hamartoma common in Asians and affects about 0.6% of the population.[40] Clinically,nevus of Ota presents as a bluish hyperpigmentation along the distribution of the trigeminal nerve. QS ruby, QS alexandrite,and QS 1064-nm Nd:YAG lasers have all been used to achieve good therapeutic results.[41] Watanabe and Takahashi[42]evaluated 114 nevus of Ota patients treated with a QS ruby laser and reported a good-to-excellent degree of lightening afterthree or more treatment sessions. Kono et al.[43] confirmed these findings when they reviewed 101 nevus of Ota patients 12months after they had been treated with a QS ruby laser and found that 56% reported over 75% clearing and 36% achievedcomplete clearing. Hypopigmentation was seen in 17% of patients and hyperpigmentation in 6%. Studies comparing the useof QS alexandrite with QS 1064-nm Nd:YAG lasers found the former to be better tolerated but the latter more effective afterthree or more sessions.[44,45] The risks of hypo- and hyperpigmentation were similar in both treatment groups, with 15%hypopigmentation and 3% hyperpigmentation reported at all treated sites. The risk of recurrence is estimated to be between0.6% and 1.2%,[43] which has important implications when treating pediatric patients.

2.5 Acquired Bilateral Nevus of Ota-Like Macules or Hori's MaculesAcquired bilateral nevus of Ota-like macules or Hori's macules is a condition that affects 0.8% of the Asian population. Horiet al.[46] described bluish-brown hyperpigmentation typically affecting the bilateral malar regions, forehead, and temples ofmiddle-aged women with no mucosal involvement. Histopathologic findings typically show a circumscribed melanocytosis inthe middle and upper dermis.[47] The disorder often coexists with other pigmentary disorders such as melasma andlentigines. QS ruby, QS alexandrite, and QS 1064-nm Nd:YAG lasers have been shown to be effective in the treatment ofHori's macules (figure 2).[48-50] However, shorter treatment intervals and more treatment sessions appear to be necessaryfor a good result. Transient post-operative hyperpigmentation is a common adverse event, occurring in the majority oftreated subjects.[49,50] Permanent hypopigmentation has been reported after treatment with a QS ruby laser.[48] A recentstudy has proposed use of a QS 532-nm Nd:YAG laser followed by a QS 1064-nm Nd:YAG laser to obtain a greater degreeof improvement.[51]


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Figure 2.

Treatment of Hori's macules using a Q-switched ruby laser: (a) pre-treatment; (b) post-treatment.

3. Non-Ablative Skin Rejuvenation in AsiansNon-ablative skin rejuvenation with a laser/light source has gained much popularity in skin of color due to the lower risk ofcomplications and limited downtime.[14] Non-ablative skin rejuvenation involves the use of a laser or light source with acooling device to improve the signs of photoaging, which include lentigines, telangiectasia, increased pore size, uneventexture, wrinkles, and skin laxity. Cooling is particularly important in skin of color as it protects the epidermis and reduces therisk of erythema and edema, which may lead to subsequent PIH. Green and yellow lasers/light sources (532-nm Nd:YAG,585- or 595-nm PDL) target the epidermal pigment and papillary dermal vessels. Injury to dermal vessels and microvascularsupply of sebaceous glands reduces telangiectasia and sebum production, in addition to promoting new collagen formationduring the healing process.[14,52] Near infra-red and infra-red lasers/light sources (1064-nm Nd:YAG, 1320-nm Nd:YAG,1450-nm diode, 1540-nm erbium:glass) together with a cooling device target water in the dermis and, throughphotothermolysis, cause a rise in dermal temperature, resulting in collagen tightening and increased collagen production.[4]Monthly treatments are required for a good effect (figure 3).


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Figure 3.

Photorejuvenation using non-ablative laser devices: (a) pre-treatment; (b) post-treatment.

More recently, a combination approach that uses different lasers and light sources in the same treatment session at monthlyintervals has been advocated.[14,53] This approach targets different skin chromophores and means optimal results can beachieved. When a combination approach is used, a lower fluence should be used for each device to reduce adverse effectsdue to cumulative heat generation.

Deep-tissue heating using unipolar radiofrequency and newer infra-red light sources affect the deep dermis and achieveenhanced skin tightening. This approach is particularly effective for elevating the eyebrows, treating peri-orbital wrinkles, andcontouring the lower face and jawline.[14,54] With effective cooling, the epidermis is protected and PIH is rare even in darkerskin types.[55] Unipolar radiofrequency, using multiple passes at a low fluence, is an effective skin-tightening device andresults in little discomfort and few complications.[56]

IPL sources that emit radiation in the infra-red spectrum have also been used to achieve deep-tissue heating withsubsequent skin tightening. Prolonged exposure with pulse width ranging from 6 to 9 seconds is required to heat up thedeep dermis. Contact cooling is again used to protect the epidermis and reduce the risk of PIH.[14]

In patients with more severe degrees of photoaging, fractional resurfacing can be useful for wrinkle and pigment reductionas well as acne scarring. By using a high fluence and low density (15 mJ, 1000 MTZ/cm2), dermal collagen remodeling isinduced with minimal epidermal injury. The newer generation of fractional resurfacing laser devices allows for changes inspot size with higher energy and, thereby, permits a greater degree of penetration with a reduction in bulk tissue heating. Inskin of color, the principle of minimizing post-treatment erythema in order to reduce the risk of PIH is a useful one. Hence, a


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reduction in energy and density as well as lengthening of treatment intervals (2-4 weeks for epidermal lesions, 4-6 weeks fordermal lesions) can also be helpful in reducing the risk of PIH.[14]

4. Common Skin Diseases in AsiansA survey of 74 589 Asians over a 2-year period in Singapore[57] listed the most common diagnoses as atopic dermatitis,acne, and viral infections. The survey identified more cases of urticaria in the Chinese, more psoriasis and alopecia inIndians, and, unsurprisingly, more PIH in Malays and Indians, who tend to have darker skin compared with the Chinese.

4.1 Atopic DermatitisAtopic dermatitis (eczema) is a common presenting complaint in all dermatology clinics. There is some evidence suggestingthat eczema is more common in the Chinese population. A survey of the 12-month cumulative incidence of atopic dermatitisin Chinese, Vietnamese, and White infants born in Melbourne, VIC, Australia showed that 44% of Chinese, 17% ofVietnamese, and 21% of White infants were affected.[58] A higher incidence of atopic dermatitis was also seen in Chineseinfants compared with White infants living in San Francisco, CA, USA and Honolulu, HI, USA.[59]

However, a study conducted in Leicester, UK, found that although there were more referrals of atopic dermatitis to thedermatology department from the Asian community, the incidence was in fact the same in the Asian and non-Asiangroups.[60] These investigators suggested a poor knowledge of atopic dermatitis amongst the Asian community as thereason for the higher rates of referral. Interestingly, there were frequent anecdotal reports from Asian patients of theirdisease resolving when they visited India or Africa and flaring up on their return to the UK, suggesting an environment-related influence on disease expression.

Management of atopic dermatitis is similar in the different ethnic groups, and includes emollients, topical corticosteroids,topical tacrolimus, phototherapy, oral antihistamines, and immunosuppressants in resistant cases.[61]

4.2 AcneA population-based prevalence study of acne in Hong Kong adolescents reported 91.3% of their subjects to be affected.[62]The majority (52.6%) of the subjects developed scarring and pigmentation as a result of acne but only 2.4% had consulted aclinician. 26.6% were also disturbed psychologically by acne and 82.9% by its physical appearance. Topical medicationswere the mainstay of treatment. The study highlighted the importance of public education of the management of thisexceedingly common condition, as well as early and aggressive intervention from clinicians, in order to prevent serioussequelae such as pigmentary changes, scarring, and psychological disturbances.

The acne hyperpigmented macule is common in skin of color and persists for an average of 4 months or longer.[63] Ice-pickscarring or keloidal scarring may also occur and can have a significant impact on the self-esteem of affected individuals.

Treatment modalities for acne include topical antibacterials, retinoids, adapalene, azelaic acid, oral antibacterials, hormonaltreatments, and oral isotretinoin. Tetracyclines are effective against acne but can be phototoxic. Strict sun avoidance andprotection are therefore essential when using tetracyclines, especially in skin of color. Macrolides such as erythromycin andclarithromycin are non-phototoxic and should be considered as first-line antibacterial treatment in Asians.[62] Bleachingagents such as hydroquinone may be used alone or in combination with other retinoids and corticosteroids for treatment ofthe acne hyperpigmented macule.[63]

Ablative laser resurfacing using carbon dioxide and erbi-um:YAG lasers has been shown to be effective in the treatment ofatrophic acne scars.[64-66] Clinical improvements of 30-75% can be achieved for patients with superficial atrophic acnescars. However, this approach is associated with significant downtime and adverse effects, which include erythema,hyperpigmentation, and hypopigmentation, that may be permanent.

Different wavelengths within visible radiation have been used to treat acne. Blue light causes activation of endogenousporphyrins in Proprionibacterium acnes and kills the bacteria.[67] However, in Asian patients, an increase in pigmentationcan occur after prolonged blue light exposure and this is therefore not an ideal treatment modality in skin of color.[14] PDLtargeting hemoglobin has been suggested to be effective in the treatment of inflammatory acne with few adverse effects.[68]However, inconsistent findings have been reported and further confirmatory studies are required.[69] Photodynamic therapy,


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using a variety of visible wavelengths and a number of photosensitizing dyes, has been used to treat acne.[70,71] A previousstudy showed a statistically significant clearance of inflammatory acne by topical aminolevulinic acid (3-hour occlusion) andred light for at least 20 weeks after four treatments, and for 10 weeks after a single treatment.[72] Significant adverse effectssuch as transient hyperpigmentation, exfoliation, and crusting were observed. In Asians, short-contact aminolevulinic acid(10-hour occlusion) followed by activation using an IPL source can be effective against acne, with erythema being the maincomplication.[14]

Infra-red lasers are increasingly being used in the treatment of acne and acne scarring. Use of a non-ablative 1450-nmdiode laser with cryogen cooling spray for the treatment of atrophic acne scars in 57 Asian patients was evaluated by Chuaet al.[73] These investigators reported mild improvement of 16-20% after four to six treatments. Conventional single-pass,high-energy (11-12 J/cm2) treatment was used in this study. Pain, erythema, and marked PIH in 39% of treated patientswere reported. Bernstein[74] recently published a pilot study demonstrating superiority of low-fluence (8-11 J/cm2),double-pass 1450-nm diode laser treatment over conventional treatment. Low-fluence, double-pass therapy reduced acnecounts and pain to the extent that a topical anesthetic could be omitted. Recently, we evaluated use of a low-fluence,multiple-pass approach in the treatment of acne vulgaris among Chinese patients and found that it was effective in thosewith inflammatory acne, with a low prevalence of PIH (figure 4).

Figure 4.

Treatment of inflammatory acne with a 1450-nm diode laser: (a) pre-treatment; (b) post-treatment.

Fractional photothermolysis is particularly effective in the treatment of acne scarring in skin of color, and indeed this is one ofthe main indications for its use. However, PIH is a potential complication of this approach. In a recent retrospective study of37 Chinese patients who underwent fractional resurfacing for acne scarring and skin rejuvenation, Chan et al.[13] concluded


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that while both energy and density parameters are important considerations for reducing PIH in Asians, density is ofparticular importance. These investigators concluded that in order to prevent PIH, a high-energy and low-density treatment ispreferable. A recent study in Asian patients by Kono et al.[75] reported similar findings and demonstrated that patientsatisfaction was also increased when higher fluence rather than higher density was used. The importance of adjunctivecooling and lengthening of the treatment interval to 2-4 weeks for epidermal lesions and 4-6 weeks for dermal lesions toreduce the risk of PIH has also been emphasized.[13]

4.3 Hypertrophic and Keloid ScarringIt is well known that hypertrophic and keloid scars are more common in individuals of Asian descent than in their Caucasiancounterparts.[76] Both types of scars are characterized by deposition of collagen and glycoprotein. However, they differclinically; keloids extend beyond the original wound whilst hypertrophic scars remain within the borders of the original wound.

Silicone gels are commonly used with some success for the treatment of keloids and hypertrophic scars. However, asuccessful outcome is highly dependent on patients adhering to the treatment regimen over a long period of time.[76] Theefficacy of corticosteroid injections in the treatment of keloids and hypertrophic scars is well established. Corticosteroidshave anti-inflammatory and vasoconstrictive effects, together with an anti-mitotic effect on fibroblasts and keratinocytes.[77]The most commonly used corticosteroid is triamcinolone. This agent is normally administered intralesionally into the scar, ata concentration of 10-40 mg/mL, every 4-6 weeks for several months or until the scar is flattened. Multiple adverse effects,including atrophy, telangiectasia, and pigmentary changes, can occur.[78,79] Recently, combined use of intralesionaltriamcinolone and fluorouracil in the treatment of inflamed hypertrophic scars has been reported to be effective and canavoid these potential complications.[80]

The 585-nm PDL appears to be effective in the treatment of keloid and hypertrophic scars. Vascular proliferation plays a keyrole in the early phase of scar formation. Through selective photothermolysis, the light energy emitted from a PDL isabsorbed by hemoglobin, generating heat and leading to coagulation necrosis.[81,82] Clinical studies of PDL treatment ofscars have noted no significant difference in treatment outcomes when minor variations in fluence were used.[83] However,there was a trend for lower fluences to be associated with greater improvement. Manuskiatti and Fitzpatrick[84] evaluated theclinical response of keloidal and hypertrophic scars after treatment with an intralesional corticosteroid alone or combinedwith fluorouracil, fluorouracil alone, and the 585-nm flashlamp-pumped PDL. They found a significant clinical improvement inall treated segments, but no significant difference between the different treatment modalities. Intralesional formulas resultedin faster resolution of scar compared with PDL. Scar texture (erythema and pliability) responded better to PDL. Anotherstudy that evaluated use of PDL in 29 Chinese patients with hypertrophic scars showed that apart from an improvement inpruritus, there was no significant difference in scar thickness between the treatment and control groups.[85] However, asupra-purpuric dose was used and excessive injury may have led to the poorer observed clinical outcome. Post-operativepurpura persisting for 7-10 days has also been reported following PDL use in other studies.[86] These findings suggest thatearly treatment with a combination of intralesional triamcinolone and fluorouracil to flatten the scar, followed by sub-purpuricPDL to improve color, texture, and pruritus, may be the most effective approach.

4.4 PsoriasisPsoriasis was the seventh most common skin condition in a large Asian patient survey conducted in Singapore.[57] However,psoriasis is more commonly seen in Caucasians than in Asians and Africans, and is very rare in Native Americans andHispanics.[87] Treatments for psoriasis include topical corticosteroids, tar, calcipotriene (calcipotriol), UVB, psoralen plusUVA (PUVA), and other oral immunosuppressants such as methotrexate, acitretin, and cyclosporine (ciclosporin). Aninteresting study examining 4294 long-term PUVA patients in Japan, Korea, Thailand, Egypt, and Tunisia found no apparentincreased risk of non-melanoma skin cancer with long-term PUVA therapy in Asian patients.[88] This is in contrast to theCaucasian experience, for which strict PUVA therapy guidelines exist because of the increased risk of cutaneousmalignancies. Phototherapy is therefore a useful long-term treatment option for Asians with psoriasis and other skinconditions such as vitiligo, cutaneous T-cell lymphoma, and atopic dermatitis.

4.5 Primary Cutaneous AmyloidosisPrimary cutaneous amyloidosis presents most commonly as either lichen or macular amyloidosis. It is a condition commonlyseen in southeast Asia and some South American countries.[89] Lichen amyloidosis is a persistent, pruritic, popular, andplaque-like eruption with a predilection for the shins and extensor arms, and is most commonly seen amongst the Chinese.


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Macular amyloidosis presents as small brown macules coalescing into patches distributed typically in a rippled, symmetricpattern on the upper back, limbs, chest, and buttocks. It most commonly presents together with lichen amyloidoisis asbiphasic amyloidosis. Histologically, deposits of amyloid are seen in the papillary dermis, and the diagnosis can easily beconfirmed by staining the amyloid red using congo red or metachromatically using crystal violet or toluidine blue.[90,91]

Anosacral amyloidosis is a rare form of cutaneous amyloidosis reported previously in Chinese and Japanese patientsonly.[92] It presents as pruritic, well demarcated, brownish patches or plaques fanning out in lines from the anus to the sacralregion. It is more common in men. This condition can be easily mistaken as lichen simplex chronicus, PIH, and tinea crurisand a skin biopsy should be carried out if the diagnosis is in doubt.

Treatment of cutaneous amyloidosis can be difficult. Reducing friction to the skin is important. Topical high-potencycorticosteroids, oral retinoids, and cyclophosphamide have also been reported to be beneficial.[93]

4.6 Kawasaki DiseaseKawasaki disease is an acute febrile vasculitis that may lead to coronary artery abnormalities. It has a much higherincidence in Asian children.[94,95] The diagnostic criteria include fever (>38.3C) of 5 days duration plus at least four of thefollowing five criteria: (i) peripheral extremity changes; (ii) polymorphous exanthem; (iii) non-purulent bilateral conjunctivalinjection; (iv) changes in the lips and oral cavity, such as erythema and strawberry tongue; and (v) acute, non-purulentcervical adenopathy.[96] The polymorphic cutaneous eruption lasts 10-20 days and then subsides. One to two percent ofpatients may die of a myocardial infarction soon after apparent recovery from the acute illness.[91]

Diagnosis of Kawasaki disease is very important because steps to prevent coronary aneurysm and myocardial infarction canthen be taken. All patients should be hospitalized during the acute febrile stage, and a baseline echocardiogramperformed.[91] A single dose of intravenous -globulin at 2 g/kg should be given over a 10- to 12-hour infusion. Aspirin(acetylsalicylic acid) should also be started at 100 mg/kg/day until the fever is controlled or until day 14 of the illness,followed by 5-10 mg/kg/day until the sedimentation rate and platelet count are normal. The patient should have a repeatechocardiogram 3-4 weeks after onset of fever. If both echocardiograms are normal, no further imaging needs to be done.Patients should, however, be followed up periodically. The disease is self-limiting and the prognosis for most children is goodif an early diagnosis is made.[91] Studies have shown that a delay in diagnosis of >10 days or occurrence in infants aged 3 mm and 37% of these 9 mm. A study from Japan also reported the foot as the most


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commonly affected area with 50% being the acral lentiginous melanoma type.[100] A large percentage also presented withadvanced disease, with 30% demonstrating metastases and a poor prognosis.

Figure 5.

Melanoma on the plantar aspect of the foot.

Delays in diagnosis and treatment of melanoma are possibly due to lack of public and physician education and preventativescreening programs in Asian countries. There is often a misconception that darker skinned individuals do not develop skincancer. The sites of melanoma occurrence are also unexpected and difficult for patients to examine. In addition, acral tumorstend to be intrinsically more aggressive and therefore present at a later stage, leading to poorer prognosis.[102] Bothphysicians and patients therefore need to maintain a high index of suspicion for melanomas regardless of ethnicity andparticular attention needs to be paid to palms, soles, fingers, toes, subungual areas, and mucosal surfaces in Asian patients.

5.2 Non-Melanoma Skin CancerBasal cell carcinoma (BCC), followed by squamous cell carcinoma (SCC), are the most common skin cancers in Chineseand Japanese individuals.[98,100,103] In Singapore, the incidence of BCC increased at a rate of 2.8% per year between 1968and 1997, while the rates of SCC decreased by 0.9% yearly.[98] Chinese individuals, who are generally of lighter skin type,were twice as likely to develop BCC and SCC as the darker skinned Malays and Indians. In a survey conducted between1983 and 1987 of the Japanese population living in sunny Hawaii, USA, the incidence per 100 000 was 60 for BCC, 48 forSCC, and 22 for Bowen disease.[104] The incidence of BCC in Japanese individuals living in native Japan was much lower,at 16.5 per 100 000, demonstrating the harmful effects of UV radiation.[105]

Known risk factors for BCC and SCC include UV exposure, Fitzpatrick skin types I-III, male sex, chemical and radiationexposure, burn or scar injuries, genetic disorders such as xeroderma pigmentosum, Gorlin syndrome, immunosuppression,and infection with human papillomavirus.[106] Photoprotection and early diagnosis can often lead to a better outcome.

5.3 Cutaneous T-Cell LymphomaMycosis fungoides or cutaneous T-cell lymphoma is the fourth most common skin cancer amongst the Japanese.[106]Hypopigmented mycosis fungoides, with ill-defined, often pruritic, hypopigmented macules and patches, tends to present ina younger patient population and only in skin of color (figure 6).[107,108] The disorder can often be mistaken for vitiligo,pityriasis alba, tinea versicolor, or post-inflammatory hypopigmentation. Misdiagnosis can delay treatment. There is usually agood response to PUVA, UVB phototherapy, or topical mechlorethamine (chlormethine), but recurrences are common. Theoverall prognosis is good.[109]


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Figure 6.

Hypopigmented mycosis fungoides.

6. Other Esthetic ProceduresOver the last few decades, there has been a surge of interest in, and performance of, esthetic enhancement procedures inAsian countries. There has also been a greater cultural acceptance of esthetic modification and skin rejuvenation usingnon-surgical techniques to reduce the stigmata of aging.

6.1 Botulinum Toxin Type AAlthough wrinkling occurs later in Asians compared with Caucasians, rhytides appear in the same predictable manner as aresult of repetitive action of facial musculature. Botulinum toxin type A (Botox; Allergan, Irvine, CA, USA) blocks the releaseof the neurotransmitter acetylcholine at the neuromuscular junction, thereby causing paralysis of the affected muscle. It wasfirst reported to be an effective treatment of fine facial wrinkles in the 1990s.[110] Anh et al.[111] found no difference in thelongevity of treatment and the amount of toxin required for Asian skin despite the increased dermal thickness and collagencontent of the skin of Asian people. Common injection sites for elimination of facial hyperkinetic wrinkles include the lateralcanthal area, glabellar area, forehead, and nasal dorsum. Repeated injections are generally required every 4-6 months.[112]Flynn et al.[113] showed that botulinum toxin injected concomitantly into lateral and infra-orbital areas results in successfulimprovement in infra and peri-orbital wrinkles and also widens the eye. The results were especially notable in Asians.

Botulinum toxin can also be used to reduce a prominent mandibular angle, the so-called 'square jaw,' in Asians. Kim etal.[114] followed up 383 patients who received botulinum toxin injection (100-140 U) [Dysport; Ipsen Ltd, Slough, UK] intothe inferior masseter borders and found an average 31% reduction in masseter hypertrophy on ultrasound 3 months aftertreatment (figure 7). Ninety-three percent of patients were positive about the outcome. Re-injection was required after 4-7months. Mild fatigue after vigorous chewing was the main complaint, followed by transient awkwardness when smiling. Morerecently, botulinum toxin A has also been used for contouring of enlarged gastrocnemius muscles with no functionaldisabilities. The improvement was well maintained for 6 months.[115,116]


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Figure 7.

Use of botulinum toxin type A for masseter hypertrophy: (a) pre-treatment; (b) post-treatment.

6.2 Soft Tissue Fillers for Tissue AugmentationAsian patients, like their Western counterparts, are increasingly seeking a more youthful face with fewer wrinkles and fullerfeatures. Fillers are therefore increasingly being used in the management of facial lines, lip augmentation, and treatment ofdistensible atrophic facial scarring. Fillers can be divided into two groups; biodegradable materials that are used fortemporary augmentation, such as hyaluronic acid and bovine collagen, or non-biodegradable materials, such as silicon oil orpolymethylmethacrylate in combination with bovine collagen, which require some time to obtain a permanent result becauseof encapsulation. The ideal filler is a non-allergenic, non-toxic, non-migratory replacement for lost collagen or subcutaneousfat. It should be easy to use with a direct result and no adverse effects.

Skin reactions to bovine serum collagen have been well documented, and double skin testing is recommended.[117] Theremay also be a risk of variant Creutzfeldt-Jakob disease or other pathogenic infections when materials derived from animalorigins are used. Hyaluronic acid fillers such as Restylane (Q-Med, Uppsala, Sweden) and Hylaform (Biomatrix, Inc,Ridgefield, NJ, USA) are marketed as having minimal allergy risk and not requiring skin testing. Studies comparing theefficacy and tolerability of Restylane with those of the bovine collagen Zyplast (McGhan Medical Inc., Santa Barbara, CA,USA) have found Restylane to be superior in effectiveness and longevity.[118] However, 0.42% of a study population of 709developed delayed skin reactions. Nevertheless, this is a much lower rate than that reported for bovine collagen, which isbetween 3% and 4%.[117,119] Hyaluronidase can resolve any undesirable effects of Restylane.[120]

Artecoll (Rofil Medical International, Breda, the Netherlands) is used as a long-lasting, deep dermal augmenting agent. It


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consists of microspheres of polymerized methylmethecrylate in a bovine collagen vehicle. A randomized controlled,multicenter, clinical trial of 251 subjects reported Artecoll to be superior in terms of facial fold reduction and patientsatisfaction after 6 months compared with collagen.[121] Early lump formation, especially in the lips, may occur in patientstreated with Artecoll and is thought to be due to excess movement prior to full encapsulation by host fibrin and fibrinogen.Talking should be minimized in the early days or concurrent use of botulinum toxin may be considered. Granuloma formationis very rare and usually occurs 6-24 months after injection. The granulomas resolve spontaneously after 4-6 years.Intralesional triamcinolone may speed up the process.[122,123] A good technique is important for reducing complications.

Poly-L-lactic acid (New-Fill; Ashford Aesthetics Inc., Brussels, Belgium or Sculptra; Aventis Pharmaceuticals,Bridgewater, NJ, USA) has been used for the correction of HIV-related facial lipoatrophy and cosmetic rejuvenation ofnon-HIV patients.[124] Temporary edema and bruising are common adverse effects. However, a report by Beljaards et al.[125]described three cases with serious giant cell granulomatous reactions after use of New-Fill or Sculptra. Intralesionalcorticosteroid therapy and topical imiquimod were moderately effective for resolving these reactions.

7. Regulatory IssuesThere is a lack of regulation of the use of lasers and esthetic procedures in most Asian countries. As a result, beauticiansworking at beauty parlours and medical spas are offering esthetic enhancement procedures with no formal training and posea significant risk to their clients. Strict policies should be in place to restrict the use of lasers and the performance of estheticprocedures to medical specialists such as dermatologists and plastic surgeons for the safety of patients.

8. ConclusionWith evolving demographics, there will be an increasing number of Asians presenting to dermatology outpatient clinics.Increased epidermal melanin is photoprotective against UV damage. However, it is also responsible for causing severalpigmentary conditions that can be particularly troublesome to Asians in their quest for fair porcelain skin. Management ofAsian skin requires different considerations than when dealing with Caucasian skin, and development of laser technologythat protects epidermal melanin from damage makes laser surgery increasingly safe in skin of color. Awareness ofcutaneous disorders that are common or particular to skin of color is also important, especially for clinicians who work inareas with a large Asian community.

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Acknowledgments

No sources of funding were used to assist in the preparation of this review. Dr Chan has acted as a consultant to Palomar,Danish Dermatologic Development, and Thermage; has been an Advisory Board member for Laserscope, CureLight,Johnson & Johnson, and Galderma; has received clinical trial grants from Palomar, Danish Dermatologic Development,Candela, and Syneron Medical; and holds stock in Reliant Technologies and CureLight. Dr Ho has no conflicts of interestthat are directly relevant to the content of this review.

Reprint Address

Dr Henry H.L. Chan, 13/F Club Lusitano, 16 Ice House Street, Central, Hong Kong SAR, China. E-mail:[email protected]

Am J Clin Dermatol. 2009;10(3):153-168. 2009 Adis Data Information BV

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