ABSTRACT
In a prospective clinical study corneal endothelium cell density was measured by means of contact specular microscopy prior to and 2, 4 and 12 weeks after Nd-YAG laser treatment. Two different laser techniques were applied: 19 eyes with narrow-angle glaucoma were treated by laser iridotomy, 21 eyes with open-angle glaucoma underwent laser treatment of the trabecular meshwork. The Nd-YAG laser was driven in Q-switched mode (nanosecond range) for iridotomy and in free-running mode (millisecond range) to treat the trabecular meshwork. A mechanical effect (iridotomy) as well as a thermal effect (LTP) of the Nd-YAG laser source was used. The morphometric study of the corneal endothelium revealed a variable increase in cell size, occasional cell loss, and an increase in polymorphism after Nd-YAG laser treatment. The decrease in endothelial cell density was not statistically significant (p = 0.01) for either laser technique. Possible mechanisms and risk factors responsible for endothelial cell loss are discussed.