PROCEEDINGS ARTICLE | February 20, 2009
Proc. SPIE. 7186, Optical Diagnostics and Sensing IX
KEYWORDS: Blood, Skin, Nd:YAG lasers, Reflectivity, Laser irradiation, Optical clearing, In vivo imaging, Tissue optics, Q switched lasers, Pulsed laser operation
The inherent barrier function of the stratum corneum (SC) makes optical clearing agents difficult to penetrate into skin.
To date, several physicochemical methods have been studied to enhance skin optical clearing. In this study, the rat skin
was initially irradiated by various light (Carbon-Dioxide Laser, Intensed Pulse Light, Nd:YAG Laser and its
frequency-doubled laser) with different dose, and then topically applied anhydrous glycerol. A fiber spectrometer was
used to monitor the change of skin diffuse reflectance spectrum so as to evaluate the optical clearing effect on skin. The
results showed that Nd:YAG Laser(1,064 nm) with appropriate pulse width and energy density combined with glycerol
could improve skin optical clearing effectively, and that Q-switched Nd:YAG Laser combining glycerol made the most
significant decrease of skin diffuse reflectance. However, after the irradiation of Carbon-Dioxide Laser (ultra-pulsed),
Intensed Pulse Light (400-700 nm) or frequency-doubled Q-switched Nd:YAG Laser(532 nm), the following application
of glycerol didn't lead to skin optical clearing. Adversely, higher power of the former two light could result in erythema,
the later one may harm skin apparently even lead to blood coagulation dot. This study provids a new idea to find out a
noninvasive but high-effective approach to increase skin optical clearing, and available parameters of laser need to be
further investigated.
