Abstract
The evolution of the laser as a medical device has been a process of continued improvement. Research into increasing our understanding of the optical characteristics of skin has made it possible to concentrate not on the effects of any particular laser system, but on basic biologic and physical principles of laser-tissue interaction. The lasers available in the 1960s and 1970s offered few possibilities for modification. However, modern technology allows us to manipulate the physical characteristics of lasers and design them for specific therapeutic purposes. Selective photothermolysis relies on chromophore-specific absorption of a brief pulse of light to generate and confine heat to certain targets within the skin without nonspecific thermal damage to adjacent structures. Thermally mediated target alterations can be confined from the level of large multicellular tissue structures (e.g., blood vessels) to individual microscopic pigmented structures (e.g., tattoo pigment granules). The purpose of this report is to describe the current progress being made and to summarize the present theories for achieving increasing selective removal, without scarring or other skin textural changes, of cutaneous vasculopathies and tattoo pigment by pulsed laser.