Visible lesion thresholds from near-infrared pico- and nanosecond laser pulses in the primate eye

Minimum visible lesions (MVL) are reported for picosecond and nanosecond laser pulses at near-IR wavelengths in the primate eye, Macaca Mulatta. The 50 percent probability for damage (ED50) dosages are reported for the 24 hour for both MVL and fluorescein angiography visible lesion thresholds at the 95 percent confidence level. The thresholds decreased by as much as 48 percent between the 1- hour reading and were lower in all cases at 24 hours. MVL- (ED50) threshold doses were 19.1 uJ at 7 ns and 4.2 uJ and 4.6 uJ at 80 ps and 20 ps respectively. Our thresholds measured for the near-IR laser pulses were lower by a factor of 4 to 8 lower than previously reported values but almost an order in magnitude higher than visible MVL thresholds for similar pulsewidth in the visible wavelengths.

Duke Scholars

Author Cynthia Ann Toth Ophthalmology, Vitreoretinal Diseases & Surgery