Optimal parameters for laser treatment of leg telangiectasia.

BACKGROUND AND OBJECTIVE The optimal parameters for treatment of leg telangiectasia with a pulsed laser are investigated. STUDY DESIGN/MATERIALS AND METHODS The Monte Carlo method is used to calculate the light penetration and absorption in the epidermis, dermis, and the ectatic blood vessel. Calculations are made for different diameters and depths of the vessel in the dermis. In addition, the oxygen saturation of the blood vessel, the laser beam diameter, and the laser irradiation profile is varied. RESULTS It is found that for vessels with diameters between 0.3 mm and 0.5 mm wavelengths about 600 nm are optimal to achieve selective photothermolysis for the considered damage model. It is also shown that an elliptical laser beam area has advantages compared to a circular beam area for treatment of leg telangiectasia. CONCLUSIONS We recommend the treatment of leg telangiectasia with dye laser wavelengths longer than the normally used 577 nm and 585 nm.