Transscleral iridotomy using a neodymium: YAG laser operated both with standard equipment and an optical fiber system--a preliminary report: Part II--Light and electron microscopic findings.
We report the morphology of transscleral iridotomies applied to human cadaver eyes using a free-running Nd:YAG laser (pulse duration: 20 ms, pulse energy: 1.5-6 J) with and without a fiber optic system. The pigment epithelium, which represents the barrier to the aqueous humor for passing through the iris, is damaged and blasted away over great areas. The mesothelial layer at the anterior surface of the iris is also broken up by the laser beam. Using low pulse energies, the iris stroma is only partially damaged. The destruction of the iris is caused by generation of heat due to absorption of radiated energy.
D005336:Fiber Optic Technology; D006801:Humans; D066298:In Vitro Techniques; D007498:Iris / Q000601:surgery* / Q000648:ultrastructure; D053685:Laser Therapy / Q000295:instrumentation; D008854:Microscopy, Electron; D055100:Optical Fibers