Port-wine stain treatment is wavelength independent in the range 488–620 nm using 200-ms pulses (original) (raw)

To investigate the possible wavelength dependency of vascular damage to port-wine stains, an argon pumped dye laser was used at wavelengths varying from 488 to 620 nm with a spot size of I mm diameter, power density of 127 W cm -2 and pulse length of 200 ms. Clear differences in tissue reactions for different wavelengths could not be observed, either clinically or histologically. During the relatively long exposures a considerable part of the heat produced in the vessel is conducted away to the surrounding tissue. Additionally, dermal damage results from heat conducted from the epidermis. These effects probably override the effect of changing the wavelength.