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DictionarySeelaseryag laser
yag laser[′yag ‚lā·zər] (optics) yttrium-aluminum-garnet laser YAG laser
YAG laser Yttrium-aluminum-garnet laser, Nd:YAG–neodymium:yttrium-aluminum-garnet–laser. See Laser. laser (lā′zĕr) [Acronym for light amplification by stimulated emission of radiation] A device that emits intense heat and power at close range upon a very small target by converting various frequencies of light into a small, extremely intense unified beam of a single frequency or wavelength. Lasers can influence cellular chemistry (the photochemical effects) and damage tissues by generating heat (e.g., producing coagulation, the photothermal effects). They can drill into, cavitate, or explode tissues (photomechanical effects) and can ablate tissues after transforming them into plasma. Lasers can also be used diagnostically (e.g., by illuminating cells or tissues, as in fluorescence). They have many applications in laboratories and in surgical procedures. In ophthalmology, they are used to treat cataracts, diabetic retinopathy, macular degeneration, and retinal detachment; in cardiology, to vaporize arterial obstructions; in dermatology, to obliterate blood vessels and to remove warts, skin cancers, nevi, excess tissue, and tattoos; in gynecology, to remove vulval lesions, including genital warts; in gastroenterology, to control bleeding in the gastrointestinal tract; and in oral surgery and dentistry, to remove tumors. Many kinds of lasers are used depending upon the wavelength and power required, including argon, carbon dioxide, copper vapor, dye, excimer, helium-neon, ion, krypton, neodymium:yttrium-aluminum garnet, and ruby lasers. CAUTION!Laser safety precautions must be observed: Warning signs should be posted indicating that a laser is being used; equipment must be checked before the procedure; conventional endotracheal tubes must be wrapped with aluminum foil tape (flexible metallic endotracheal tubes insulated with silicone may be used); skin preparation solution may not contain combustible agents; and towels draped around the site must be kept wet. The laser equipment must be moved carefully to avoid jarring the mirrors out of alignment. Alcohol-based skin preparations should not be used.argon laserA gas-produced laser (in the blue and green visible light spectrum) with a wavelength 488 nm to 633 nm, used in the coagulation of tissue and in photodynamic therapy. Argon lasers are used to treat skin lesions, bleeding ulcers, hemangiomas, periodontal disease, glaucoma, and retinal diseases. carbon dioxide laser Abbreviation: CO2 laser A gas-produced colorless laser with a wavelength of 10,600 nm (infrared), used in dermatological surgeries to remove scars, wrinkles, and solar skin damage. Carbon dioxide lasers can also be used as a scalpel in stereotactic neurosurgeries and gynecological surgeries. Patient careLaser precautions must be observed. The staff support the patient by answering questions and explaining the need for eye covering during the procedure. The procedure is documented in a laser log. cutaneous laserAny of several lasers, e.g., argon, CO2, used for cosmetic and plastic surgery. The procedures include treatment of pigmented lesions, wrinkles, vascular malformations, and other skin surface irregularities. diode laserA compact laser designed with semiconductors, with wavelengths from 800 to 1000 nm, used in skin, eye, and urological surgeries.Patient careCare involves general support, giving explanations, and answering questions. Equipment must be checked and regulations followed, esp. those that involve fire safety. The surgeon is given assistance, as needed. dye laserA laser with wavelengths of 510 nm for green and 577 nm–600 nm for yellow, whose energy reacts with various dyes and, modified by a tunable crystal, is applied in pulses, used primarily to manage skin lesions.Patient careCare involves giving general emotional support, explanations, and answering questions regarding the procedure. The equipment is checked, and all rules are observed. The needs of the surgeon are anticipated, and the procedure is recorded in the laser log. excimer laserAn ultraviolet laser used to remove tissue from the cornea, e.g., in LASIK surgery, or to remove plaque from arteries. This rare gas (halide) energy source laser breaks chemical bonds instead of destroying tissue with heat; it penetrates less than 1 mm into tissue. Halide combines with an active medium (an excited dimer), from which it derives its name. The dimeric media are excited, emitting laser energy. The chemical composition of the medium determines the ultraviolet wavelength. The four most popularly used are: the argon fluoride (ArF) laser at 193 nm, the krypton fluoride (KrF) at 248 nm, the xenon chloride (XeCl) at 308 nm, and the xenon fluoride (XeFl) at 351 nm. grid laserA laser that scatters light energy across the macula; used to treat eye diseases, e.g., diabetic retinopathy.yttrium-aluminum-garnet laser Abbreviation: YAG laser A laser with a crystal made of yttrium, aluminum, and garnet, used for skin resurfacing, or tissue penetration in oral, urological, ophthalmic, cardiac, orthopedic applications. The depth of the penetration of the laser energy, its tissue absorption, and tissue-sparing characteristics vary with the materials used as additives to the crystal, e.g., erbium, holmium, or neodymium. Patient careCare involves general support, giving explanations, and answering questions. All equipment must be checked and all rules observed. The nurse assists the surgeon as necessary.
yttrium-aluminum-garnet laser Abbreviation: YAG laser A laser with a crystal made of yttrium, aluminum, and garnet, used for skin resurfacing, or tissue penetration in oral, urological, ophthalmic, cardiac, orthopedic applications. The depth of the penetration of the laser energy, its tissue absorption, and tissue-sparing characteristics vary with the materials used as additives to the crystal, e.g., erbium, holmium, or neodymium. Patient careCare involves general support, giving explanations, and answering questions. All equipment must be checked and all rules observed. The nurse assists the surgeon as necessary. See also: laser |