A host of cosmetic and medical applications of lasers are being explored. From the treat­ment of tumors, vitiligo [103,104], and wound healing [105], the application of laser light is finding novel uses. As the professional use of lasers for treating a multitude of dermatological conditions con­tinues to expand in terms of the number of patients […]

There are a variety of vascular lesions which are now routinely treated with lasers [92-99]. The chromophore targeted is oxyhemaglobin. Laser treatment of vascular lesions has been used in children to manage common childhood lesions, including port wine stain and haemangiomas [100]. In adults, visible veins in the lower extremities, commonly called spider veins, are […]

As presented earlier in this chapter, the removal of tattoos was one, if not the first, use of lasers in dermatology [89]. The type of laser used varies and is, in part, dependent on the pig­ments used in the tattoo [90]. With the ever-increasing number of individuals getting tattoos [91], it will not be surprising […]

Treatment of photo – and chronological-aging of skin by laser resurfacing is another cos­metic use of lasers [85-88]. Generally, this is an aggressive, infrequent treatment. Treat­ments such as microdermabrasion, chemical peels, and laser skin rejuvenation have gained popularity as aging “baby-boomers” search for solutions to combat intrinsic and photoag­ing of the skin.

One of the oldest, established uses of lasers is the so-called permanent hair removal [71,72]. This procedure has been performed with lasers including ruby [73], alexandrite [74], diode [23], Nd:YAG [75], and IPL [76]. The procedure using these devices is generally considered safe and effective. 23.3.3 Pigmentary Lesions It has been debated that one of […]

A very brief overview of some nonablative clinical uses of lasers is presented. This highlights the most common therapeutic uses for which the safety/adverse events have been evaluated. 23.3.1 Acne Lasers have been used to treat acne [32,56-58], alone or as part of a photodynamic regi­men [59-61], and to reverse/correct the scarring produced by more […]

The principles used in toxicological risk assessment, are: (i) hazard identification, (ii) dose-response, and (iii) exposure. In considering the hazard identification for laser devices, the mechanism or mode of action is particularly important. Specifically, by knowing the mode/mechanism of action and information around dose-responsivity, the adverse event profile can be predicted. In this regard, the […]

23.2.1 Chromophores in the Skin Skin optics has been evaluated by multiple investigators with the intent of improving phototherapy [36-38]. Though the optics of human skin is extraordinarily complex, there are a few key considerations, as it relates to lasers and human safety. When considering transmission of light into tissue, there are three components: (i) […]

In photobiology/phototoxicology, it is essential to understand “dose” in order to com­prehend the consequences of light exposure. Perhaps the most basic property when con­sidering electromagnetic radiation is that energy (E) is inversely proportional to wavelength or E = hc ^ X, where h equals Planck’s constant, c equals the speed of light in a vacuum, […]