excimer laser

laser /la·ser/ (la´zer) a device that transfers light of various frequencies into an extremely intense, small, and nearly nondivergent beam of monochromatic radiation in the visible region, with all the waves in phase; capable of mobilizing immense heat and power when focused at close range, it is used as a tool in surgery, in diagnosis, and in physiological studies.

Relative positions of various types of lasers on the electromagnetic spectrum.

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argon laser  a laser with ionized argon as the active medium, whose beam is in the blue and green visible light spectrum; used for photocoagulation.

carbon-dioxide laser  a laser with carbon dioxide gas as the active medium, which produces infrared radiation at 10,600 nm; used to excise and incise tissue and to vaporize.

dye laser  a laser with organic dye as the active medium, whose beam is in the visible light spectrum.

excimer laser  a laser with rare gas halides as the active medium, whose beam is in the ultraviolet spectrum and penetrates tissues only a short distance; used in ophthalmological procedures and laser angioplasty.

helium-neon laser  a laser with a mixture of ionized helium and neon gases as the active medium, whose beam is in the red visible light spectrum; used as a guiding beam for lasers operating at nonvisible wavelengths.

krypton laser  a laser with krypton ionized by electric current as the active medium, whose beam is in the yellow-red visible light spectrum; used for photocoagulation.

KTP laser  one in which a beam generated by a neodymium:YAG laser is directed through a potassium titanyl phosphate crystal to produce a beam in the green visible spectrum; used for photoablation and photocoagulation.

neodymium:yttrium-aluminum-garnet (Nd:YAG) laser  a laser whose active medium is a crystal of yttrium, aluminum, and garnet doped with neodymium ions, and whose beam is in the near infrared spectrum at 1060 nm; used for photocoagulation and photoablation.

potassium titanyl phosphate laser  KTP l.

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Excimer laser

An instrument that is used to vaporize tissue with a cold, coherent beam of light with a single wavelength in the ultraviolet range.

Mentioned in: Photorefractive Keratectomy and Laser-Assisted In-Situ Keratomileusis

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excimer laser

[ek′simər]

one of a class of lasers with output in the ultraviolet range of the electromagnetic spectrum. The name is derived from the symbol formed by the combination of xenon atoms (Xe) and halogen atoms (X) to yield xenon-halide compounds as XEX.

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laser [la´zer]

a device that transfers light of various frequencies into an extremely intense, small, and nearly nondivergent beam of monochromatic radiation in the visible or invisible spectrum, with all the waves in phase; capable of mobilizing immense heat and power when focused at close range, lasers act on tissues by photocoagulation and photodisruption and are used in surgery, in diagnosis, and in physiological studies.

argon laser a laser with ionized argon as the active medium and with a beam in the blue and green visible light spectrum; used for photocoagulation.

carbon-dioxide laser a laser with carbon dioxide gas as the active medium and that produces infrared radiation at 10,600 nm; used to excise and incise tissue and to vaporize.

excimer laser (excited dimer) a laser with rare gas halides as the active medium, used in ophthalmological procedures and angioplasty. The beam is in the ultraviolet spectrum and penetrates tissues only a small distance; it breaks chemical bonds instead of generating heat to destroy tissue.

holmium:YAG laser a laser whose active medium is a crystal of yttrium, aluminum, and garnet doped with holmium ions, and whose beam is in the near infrared spectrum at 2100 nm; used for photocoagulation and photoablation.

neodymium:yttrium-aluminum-garnet (Nd:YAG) laser a laser whose active medium is a crystal of yttrium, aluminum, and garnet doped with neodymium ions, and whose beam is in the near infrared spectrum at approximately 1060 nm; used for photocoagulation and photoablation.

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excimer laser

Cold laser Cardiology A laser used in coronary artery angioplasty that delivers pulsating UV light to excise atherosclerotic plaques in stenosed arteries. Cf Percutaneous transluminal coronary angioplasty Ophthamology ELs may be used to vaporize part of the surface layer of the cornea.