Lasers in Veterinary Dermatology (original) (raw)

2006, Veterinary Clinics of North America: Small Animal Practice

HISTORY OF LASERS Laser is an acronym that means light amplification by stimulated emission of radiation [1]. The stimulated emission of light and its properties was first described in the early 1900s by Einstein. Forty years later (in 1960), the first laser was developed at Bell Laboratories, and during the 1970s, lasers were introduced for use in medicine. Over the next decade, smaller and less expensive lasers were introduced and their use in medicine expanded. By late 1980s, many different types of lasers had been developed and were being used by many medical specialties, including veterinary medicine [2-8]. HOW LASERS WORK Lasers are devices that generate electromagnetic radiation that is essentially monochromatic, a single wavelength, and can be compressed into a small beam that is able to travel wide distances with little divergence. Lasers produce a high-intensity beam so intense that their light is 10 times brighter than the sun [9]. The lasers in use for medical purposes are referred to as light lasers. Light, by definition, is that portion of the electromagnetic spectrum that is visible to the human eye; however, lasers in use in medicine emit beams of radiation that are in the visible range as well as in the near-infrared or ultraviolet regions. These beams behave in the same way as the visible spectrum in that they can be focused with lenses and reflected with mirrors; thus, for simplicity, they are called light lasers [7]. Lasers are named for the medium that is used to produce the laser light beam. Each laser's properties depend on the medium used to produce the laser beam and the ways in which that beam is delivered. The laser beam's interaction with tissue depends on the wavelength, power, and time that the beam is exposed to the tissue [4]. Some lasers, for example, the Qswitched ruby laser, do not interact with the surface tissue but penetrate deeper to interact with pigmented or vascular targets, such as pigmented nevi, tattoos, or vascular lesions.