Biomedical Engineering Reference
In-Depth Information
overcooled epidermis may cool down the dermal target and
result in a decrease in the desired clinical response. The com-
mercial cooling methods/devices include passive cooling with
aqueous gel, active cooling with water or refrigerated air, and
dynamic active cooling with cryogen spray. Most of these cool-
ing devices have been used in conjunction with vascular lasers,
IPL systems, and laser hair removal.
In a less technically sophisticated manner, we fi nd that pre-
cooling and postcooling the skin with an ice pack or ice cube can
also be performed. This method, like water cooling at 0°C with
a glass window, will decrease the dermoepidermal junction tem-
perature, depending on application time. However, because it is
done manually, the effi cacy of this method may be unpredict-
able. Studies comparing cooling systems suggest that cryogen
spray cooling (CSC) and contact cooling with water encased in
a sapphire window provide the most effective/effi cient epider-
mal preservation followed by cold air, water encased in a glass
housing, and fi nally cold gel or ice (246,280).
12. Astner S, Anderson RR. Skin phototypes 2003. J Invest Dermatol 2004;
122: xxx-xxxi.
13. Lancer HA. Lancer Ethnicity Scale (LES) [letter]. Lasers Surg Med 1998;
22: 9.
14. Wolbarsht ML, Urbach F. The Lancer Ethnicity Scale [letter]. Lasers Surg
Med 1999; 25: 105-6.
15. Goldman MP. Universal classifi cation of skin type. Cosmet Dermatol
2002; 15: 53-7.
16. Battle EF Jr, Soden CE Jr. The use of lasers in darker skin types. Semin
Cutan Med Surg 2009; 28: 130-40.
17. Tanzi EL, Lupton JR, Alster TS. Lasers in dermatology: four decades of
progress. J Am Acad Dermatol 2003; 49: 1-31; quiz 31-4.
18. Anderson RR, Parrish JA. The optics of human skin. J Invest Dermatol
1981; 77: 13-19.
19. Ashinoff R, Geronemus RG. Treatment of a port-wine stain in a black
patient with the pulsed dye laser. J Dermatol Surg Oncol 1992; 18: 147-8.
20. Tan OT, Kerschmann R, Parrish JA. The effect of epidermal pigmenta-
tion on selective vascular effects of pulsed laser. Lasers Surg Med 1986; 4:
365-74.
21. Tong AKF, Tan OT, Boll J, et al. Ultrastructure: effect of melanin pigment
on target specifi city using a pulsed dye laser (577 nm). J Invest Dermatol
1987; 88: 747-52.
22. Fitzpatrick RE, Lowe NJ, Goldman MP, et al. Flashlamp-pumped pulsed
dye laser treatment of port-wine stains. J Dermatol Surg Oncol 1994; 20:
743-8.
23. Haedersdal M, Gniadecka M, Efsen J, et al. Side effects from the pulsed
dye laser: the importance of skin pigmentation and skin redness. Acta
Derm Venereol 1998; 78: 445-50.
24. Haedersdal M, Wulf HC. Pigmentation-dependent side effects to copper
vapor laser and argon laser treatment. Lasers Surg Med 1995; 16: 351-8.
25. Haedersdal M, Wulf HC. Risk assessment of side effects from copper
vapor and argon laser treatment: the importance of skin pigmentation.
Lasers Surg Med 1997; 20: 84-9.
26. Haedersdal M, Wulf HC. Pigmentation dependent, short time skin reac-
tions to copper vapour laser and argon laser treatment. Burns 1994; 20:
195-9.
27. Chan HH, Chan E, Kono T, et al. The use of variable pulse width fre-
quency doubled Nd:YAG 532 nm laser in the treatment of port-wine
stain in Chinese patients. Dermatol Surg 2000; 26: 657-61.
28. Ho WS, Chan HH, Ying SY, et al. Laser treatment of congenital facial
port-wine stains: long-term effi cacy and complication in Chinese
patients. Lasers Surg Med 2002; 30: 44-7.
29. Kono T, Sakurai H, Takeuchi M, et al. Treatment of resistant port-wine
stains with a variable-pulse pulsed dye laser. Dermatol Surg 2007; 33:
951-6.
30. Sommer S, Sheehan-Dare RA. Pulsed dye laser treatment of port-wine
stains in pigmented skin. J Am Acad Dermatol 2000; 42: 667-71.
31. Dong X, Yu Q, Ding J, et al. Treatment of facial port-wine stains with a
new intense pulsed light source in Chinese patients. J Cosmet Laser Ther
2010; 12: 183-7.
32. Ho WS, Ying SY, Chan PC, et al. Treatment of port wine stains with intense
pulsed light: a prospective study. Dermatol Surg 2004; 30: 887-91.
33. Chang CJ, Kelly KM, Van Gemert MJ, et al. Comparing the effectiveness
of 585-nm vs 595-nm wavelength pulsed dye laser treatment of port
wine stains in conjunction with cryogen spray cooling. Lasers Surg Med
2002; 31: 352-8.
34. Greve B, Raulin C. Prospective study of port wine stain treatment with
dye laser: comparison of two wavelengths (585 nm vs. 595 nm) and two
pulse durations (0.5 milliseconds vs. 20 milliseconds). Lasers Surg Med
2004; 34: 168-73.
35. Chang CJ, Nelson JS. Cryogen spray cooling and higher fl uence pulsed
dye laser treatment improve port-wine stain clearance while minimizing
epidermal damage. Dermatol Surg 1999; 25: 767-72.
36. Chiu CH, Chan HH, Ho WS, et al. Prospective study of pulsed dye laser in
conjunction with cryogen spray cooling for treatment of port wine stains
in Chinese patients. Dermatol Surg 2003; 29: 909-15; discussion 15.
37. Alster TS, Tanzi EL. Combined 595-nm and 1,064-nm laser irradiation
of recalcitrant and hypertrophic port-wine stains in children and adults.
Dermatol Surg 2009; 35: 914-18; discussion 18-19.
38. Li G, Sun J, Shao X, et al. The Effects of 595- and 1,064-nm Lasers on
Rooster Comb Blood Vessels Using Dual-Wavelength and Multipulse
Techniques. Dermatol Surg 2011; 37: 1473-9.
conclusions
The majority of laser and pulsed light treatments on Asian
skin can be performed safely and effectively. However, treat-
ments must be approached with caution. Epidermal pigmen-
tation is perhaps the most fundamental limitation because it
diminishes laser light reaching the dermis and causes unwanted
thermal damage to the epidermis. Thorough patient counsel-
ing regarding the risks of cutaneous laser treatment remains
an essential part of therapy.
Careful preoperative and postoperative treatment programs
should be used as well as a prudent selection of types of lasers
and light source suited to a patient's treatment purposes. Treat-
ment parameters (wavelength, pulse duration, and fl uence)
can be tailored for specifi c cutaneous applications to effect
maximal target destruction with minimal collateral thermal
damage. Epidermal cooling is a useful method to minimize
undesired epidermal damage. Finally, when treating an Asian
individual with any laser, a conservative approach is the best.
REFERENCES
1. United Nations DoEaSA, Population Division. World population pros-
pects: the 2010 revision. [Available from: http://esa.un.org/wpp/Excel-
Data/population.htm] [11 July 2012].
2. Berardesca E, Maibach H. Ethnic skin: overview of structure and func-
tion. J Am Acad Dermatol 2003; 48: S139-42.
3. Berardesca E, Maibach HI. Racial differences in skin pathophysiology.
J Am Acad Dermatol 1996; 34: 667-72.
4. Richards GM, Oresajo CO, Halder RM. Structure and function of ethnic
skin and hair. Dermatol Clin 2003; 21: 595-600.
5. Chan HH, Alam M, Kono T, et al. Clinical application of lasers in Asians.
Dermatol Surg 2002; 28: 556-63.
6. Ho SG, Chan HH. The Asian dermatologic patient: review of common
pigmentary disorders and cutaneous diseases. Am J Clin Dermatol 2009;
10: 153-68.
7. Chung JH. Photoaging in Asians. Photodermatol Photoimmunol Pho-
tomed 2003; 19: 109-21.
8. Alaluf S, Atkins D, Barrett K, et al. Ethnic variation in melanin content
and composition in photoexposed and photoprotected human skin.
Pigment Cell Res 2002; 15: 112-18.
9. Taylor SC. Skin of color: biology, structure, function, and implications
for dermatologic disease. J Am Acad Dermatol 2002; 46: S41-62.
10. Sykes JM. Management of the aging face in the Asian patient. Facial
Plast Surg Clin North Am 2007; 15: 353-60; vi-vii.
11. Davis EC, Callender VD. Aesthetic dermatology for aging ethnic skin.
Dermatol Surg 2011; 37: 901-17.
