Remittance at a single wavelength of 390 nm to quantify epidermal melanin concentration.
Objective quantification of epidermal melanin concentration (EMC) should be useful in laser dermatology to determine the individual maximum safe radiant exposure (IMSRE). We propose a single-wavelength remittance measurement at 390 nm as an alternative optical method to determine EMC and IMSRE. Remittance spectra (360 to 740 nm), melanin index (MI) measurements and the transient radiometric temperature increase, DeltaT(t), upon skin irradiation with an Alexandrite laser (755 nm, 3-ms pulse duration, 6 Jcm(2)) were measured on 749 skin spots (arm and calf) on 23 volunteers (skin phototypes I to IV). Due to the shallow penetration depth and independence of blood oxygen saturation (isosbestic point), remittance at 390 nm appears to provide better estimates for EMC and IMSRE than MI.
Verkruysse
Wim
W
University of California, Irvine Beckman Laser Institute, 1002 Health Sciences Road, Irvine, California 92612, USA.
Svaasand
Lars O
LO
Franco
Walfre
W
Nelson
J Stuart
JS
D004817:Epidermis / Q000378:metabolism*; D006801:Humans; D008543:Melanins / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013055:Spectrophotometry, Infrared / Q000379:methods*; D013817:Thermography / Q000379:methods
D008543:Melanins