The pulsed-dye laser for treatment of cutaneous conditions.

The concept of selective photothermolysis simply states that if one heats target tissue with a laser that is selectively absorbed by that tissue, heat should last sufficiently enough to cause damage to the target tissue, but not so long for the heat to spread to the surrounding tissue. The pulsed-dye laser (PDL) was the first laser to utilize the concept of selective photothermolysis to treat dermatologic conditions. The first application of this concept was directed at treating port-wine stain birthmarks (PWSs). A myriad of conditions that were previously only marginally treated by earlier-generation PDLs could be addressed, increasing by a factor of many thousand the number of potential patients for PDL treatment. Rosacea, scars, red striae, some lower-extremity spider veins, and photodamage could now be easily treated in addition to PWSs, nevus araneuses, cherry hemangioma, and verrucae. Finally, the latest advances in PDL technology have maximized the ability to treat linear vessels such as lower-extremity spider veins, and linear facial vessels associated with rosacea, photodamage or simply heredity, as well as improving the ability to treat diffuse erythema such as the facial redness of rosacea, PWSs, scars and striae with less risk of epidermal damage and hyperpigmentation. Final advances aim to reduce side-effects of both types of vascular lasers while potentially increasing benefits by allowing the delivery of higher fluencies. Cooling the surface of the skin protects melanin pigment while allowing the delivery of light to the dermis to remove unwanted blood vessels and potentially stimulate dermal remodeling.