Corneal injury to ex-vivo eyes exposed to a 3.8 micron laser /

by Fyffe, James G.

Title of Thesis: “Corneal Injury to Ex-vivo Eyes Exposed to a 3.8 Micron Laser” Author: Lt. James G. Fyffe Master of Science in Public Health Thesis Directed by: Dr. Thomas Johnson Assistant Professor Department of Preventive Medicine and Biometrics As a consequence of the significant expansion of laser use in medicine, industry and research, specific safety standards must be developed that appropriately address eye protection. The purpose of this study is to establish injury thresholds to the cornea for 3.8 µm 8 microsecond laser light pulses and to investigate a possible replacement model to live animal testing. Previous studies of pulsed energy absorption at 3.8 µm were performed using rhesus monkey cornea and were at pulse durations two orders of magnitude different than the 8 microsecond pulses used in this study. Ex-vivo pig eyes were exposed at varying energies and evaluated to establish the statistical threshold for corneal damage. Histologic evaluation was used to determine the extent of damage to the cornea. It is expected that the results will be used to assist in the establishment of safety standards for laser use and offer an alternative to future animal use in establishment of safety standards.