OPHTHALMOLOGICAL USE OF PULSATED NEODYMIUM YAG LASERS - PREOPERATIVE APERTURE OF LENSES PREVIOUS SETTING IN OF ARTIFICIAL LENSES AND OPENING OF SECONDARY CATARACTS BEHIND IMPLANTS
The construction of a new laser is presented. This cold laser is an ultra rapid pulsed neodymium yag [yttrium, aluminum, garnet] laser. It permits a very fine microsurgery without opening of the eye. The opening of the capsule and the softening of the nucleus are 2 examples of the surgery performed with this laser: all ocular tissues, even uncolored and semi-transparent, may be cut without heat. These studies helped in the demonstration of this laser''s mechanism of action. Under irradiation a local instantaneous energy deposit takes place and total ionization of the medium occurs; the formation of a plasma screen, after which an hydrodynamic shock wave develops from the energy zone boundary. The elevation of the temperature at the site of the impact cannot exceed 2 .times. 10-3.degree. C; at this low temperature no harm is done to the tissue.