Laser in medicine

The laser is used in medicine using its multiple effects. the interaction of the laser light with the biological tissue starts by absorbing that light. The absorbed photons, in the photochemical process, cause the destruction of the nocent cells. The choice lasers are used to correct myopia and astragmatism and to clear the obstructive artery. The photosensesor HPD is used in experimental treatment of different malignant tumors. Photodynamic treating has shown efficient in many types of cancer like that of lung, nose, throat and vesica. The method is used also in treating superficial tumors in skin . The Fluore scence property of some photosensesors and the auto fluorescence of some tissue pigments are used to detect some micro tumors. The illumination of tissue by pulsed laser for short duration is a new developed method in radiography, especially in mammography. The applications of laser are multiple in industry, such as uranium enrichment, thermonuclear fusion, are metal treatment. The effects of laser are not without risk. this is why exposure limits have been determined and the manufacturing or the use of these instruments are regulated by a group of parameters. (author). 22 refs. 5 figs