Dosimetry for lasers and light in dermatology: Monte Carlo simulations of 577 nm-pulsed laser penetration into cutaneous vessels

The role of skin optics in planning proper dosimetry for radiant energy delivered by lasers and conventional light sources is presented. The optical properties of the epidermis, dermis, and cutaneous blood are summarized. The ability of laser pulses at 577-nm wavelength to penetrate into and around a large blood vessel is studied using Monte Carlo simulations. The variation in laser penetration for variable beam diameters and variable vessel depths in presented. The distinction between TOTAL PULSE ENERGY versus PULSE ENERGY DENSITY is illustrated. The topic of this paper is especially pertinent to laser therapy for portwine stain lesions.