A Safety Test for Ocular Phototoxicity in the Rabbit After Short-term Exposure to Strong Light.

BACKGROUND/AIM: Self-defense products that use high-intensity light are being developed. The intense light generated by the high-power light-emitting diodes (LEDs) of such self-defense products causes temporary blindness. However, few studies have been conducted on the visual safety of their devices. We, therefore, evaluated the effects of strong light of a short duration on the eyes of rabbits in this study.

MATERIALS AND METHODS

The right eyes of 15 rabbits were irradiated for 5 s with a lighting device (25 W, 150 lm/W at 700 mA LED) and four eyes of two rabbits were non-irradiated as controls. Changes in the eye structure and function were evaluated before, and immediately, 30 min, 1 h, 24 h, 7 days and 14 days after light irradiation by full-field electroretinogram (ERG), slit-lamp biomicroscopy, and retinal camera. The thickness of the outer nuclear layer of the retina tissue was measured, and histopathological signs of retinal damage were analyzed.

RESULTS

The ERG results showed that night vision was not affected. In day vision, the ERG waveform was temporarily affected immediately after light irradiation; however, it recovered within 24 h. No histopathological signs of damage were observed.

CONCLUSION

Application of high-power LED light with short duration as used for self-defense was found to cause temporary phototoxicity, but safety was confirmed as vision recovered within 24 h.