Cornea epithelial damage thresholds in rabbits exposed to Tm:YAG laser radiation at 2.02 μm

摘要

AbstractWe have determined exposure conditions for minimal damage to the corneal epithelium in rabbit using a continuous wave Tm: YAG laser operating in the TEMoomode at incident powers between 80 and 450 mW. The 1/e beam diameter was 0.94 mm and exposure durations for threshold damage ranged from 4.3 to 0.08 sec. Calculated temperatureincreaseson the beam axis 10 μm beneath the surface at the measured thresholds were essentially constant and averaged 44°C. This is basically the same temperature increase found for threshold CO2laser damage and suggests that the critical temperature damage model, which correlates CO2laser damage, can predict damage thresholds for mid‐infrared laser radiation. We also showed that reliable thresholds can be determined in freshly enucleated eyes, thus opening up the possibility of using available laser sources in laboratories not equipped and approved for animal experiments to determine damage thresholds. © 1992 Wiley‐Lis