ABSTRACT
The use of an ultra short Nd Yag laser pulses is described for the opening of secondary traumatic cataract and iridocapsular synechiae. Both pigmented and non pigmented ocular tissue were cut without causing adverse thermal effects and without opening the eye. The laser instantaneous release of energy causes total ionization of the medium and formation of a plasma, followed by a hydrodynamic shock wave originating at the energy zone boundary. The temperature at the site of the laser contact cannot exceed 2 X 10(-3) degrees C, which is not harmful to the eye. Further, this procedure requires no anesthesia and does not involve introduction of foreign material into the eye. The degree of aiming accuracy, the very small diameter of the beam (50 microns) make the laser so precise that it virtually eliminates the risk of damage to the eye and/or the intraocular lens.
Subject(s)
Cataract Extraction/methods , Laser Therapy , Adolescent , Adult , Cataract/etiology , Child , Child, Preschool , Eye Injuries/complications , Female , Humans , Male , NeodymiumABSTRACT
A new laser devised and built by the authors is presented. This cold laser is an ultra rapid pulsed Neodymium Yag laser. Its permits a very fine microsurgery without opening of the eye. The opening of the capsule and the softening of the nucleus are one example of the new laser surgery daily performed in Trousseau's Eye Clinic: all the ocular tissues, even uncolored and semi-transparent may be cut without heat with this laser. The mechanism of the action is clear. According to our studies, under such an irradiation, a local instantaneous energy deposit takes place, total ionization of the medium occurs, resulting in the formation of a plasma screen, then, after an hydrodynamic shock wave develops from the energy zone boundary. The elevation of the temperature at the site of the impact cannot exceed 2.10(-3) degree C, which is totally unharmful.
