Corneal damage induced by pulsed CO2 laser radiation

Corneal damage thresholds were determined in Dutch Belted rabbits following CO2 laser radiation with pulse widths of 1.7, 25 and 250 ns. The threshold values for corneal clouding found for the 3 cases were 0.33, 0.54 and 0.18 J/cm2, respectively. These results are in accord with expectations based on a thermal-damage mechanism, with no evidence of acoustic shock or other mechanisms contributing to the observed damage for the exposure parameters used in this study. The data support the suggested maximum permissible exposure levels for short-pulse far-infrared laser radiation as quoted in current laser safety standards.