The unique properties of laser light allows specific targets within the skin to be damaged or destroyed leaving surrounding tissues unaffected. The concept of all state-of- the-art lasers and light sources is based on the principle of selective destruction of specific targets within the skin with minimal damage to surrounding structures. Such damage occurs by selecting a wavelength of light that is maximally absorbed by the targeted structure in a very short duration of the light pulse. This conceptual breakthrough has revolutionized the treatment of a large variety of cutaneous disorders.
The classic example of such therapy is the use of pulsed lasers in the treatment of vascular lesions such as port wine stains. The concept underlying the development of all of the lasers was generated in an effort to better treat the vascular birthmarks seen in children. The intense yellow light of this laser is selectively absorbed by the red/blue color of blood suffusing the birthmark, selectively damaging these vessels and inducing the port wine stain to gradually fade. The many lasers now used to treat vascular lesions are capable of treating a variety of birthmarks, dilated vessels such as is seen after chronic sun exposure or in medical conditions such as rosacea, red noses, red cheeks, vascular growths such as hemangiomas, and some scars.
Using different wavelengths the same concept may be applied to the treatment of pigmented lesions. Lasers with pulse duration of 1 millionth of a second are quite effective in treating many pigmented lesions, such as a variety of brown or black birthmarks, sun induced freckle-like pigmentation, café-au-lait birthmarks, and traumatic or decorative tattoos. Lesions may disappear entirely or require a series of treatments and there is rarely any textural, pigmentary, or scarring changes associated with this.
The ability to “pluck out” blood vessels, different types of vascular and pigmented birthmarks, and areas of abnormal pigmentation became a reality only with the discovery and use of lasers and other light sources and their ability to bring about almost magical changes in the skin.
(Updated June 3, 2010)
Source ASLMS (American Society of Laser Medicine and Surgery Inc.)