LASER RADIATION EFFECTS ON THE MORPHOLOGY AND FUNCTION OF OCULAR TISSUE.

A power spectral analysis was performed on averaged responses for a number of wavelengths and intensities of spectral light. An averaging computer was used to average at least 50 consecutive responses at each wavelength and intensity. The studies indicate that the ERG has more than one generator and there is no evidence of a single mechanism with a simple linear phase shift, energy is distributed in several frequency bands and each band has a threshold, the power spectrum contains different frequency bands as a function of wavelength, and anatomical substrates have a frequency fingerprint, and the ERG may be useful as a diagnostic tool to assess the state of the retina. The ERG of the mangabey was found to be altered by a single laser pulse of low energy density 0.2 Jsq cm which irradiated a large retinal area. ERGs recorded six or more days post-exposure showed a depression or absence of the third oscillatory potential. The implicit time of the b-wave was significantly shorter p0.001 post-exposure. Replication of the study with testing at 6-10 days and six months post-exposure revealed statistically significant post-exposure ERG changes persisting up to six months. Author