Abstract
Purpose: :
To examine the morphologic and functional changes of the primate retina after LED exposure using spectral domain optical coherence tomography (SD-OCT) and electroretinogram (ERG). The results were compared with those in normal control retina.
Methods: :
Under general anesthesia, the right eyes of 3 male monkeys (Body weight 5-10kg) were exposed to white LED light with contact for 8 hours. SD-OCT and full-field ERG (rod, flash, cone) were performed to the exposed eyes and control eyes immediately after and at post-exposure days 1 and 14. We analyzed the changes of OCT images and the maximum amplitude of ERG before and after LED exposure. The power of LED was set at 8912cd.
Results: :
Photoreceptor inner and outer segment junction (IS/OS) line was unclear and the length between IS/OS and RPE was shortened immediately after light exposure in 3 monkeys. On post-exposure day of 1, the length between IS/OS and RPE was still short but IS/OS line was incompletely recovered in all 3 monkeys. The length between IS/OS and RPE was completely recovered on post exposure days of 14. The average amplitudes of 3 monkeys in cone and rod maximum responses were significantly decreased against those of normal control eyes immediately after light stimulation (p<0.05). On post-exposure day of 1, the average amplitude of cone response was significantly low (p<0.01) but that of rod and flash recovered to normal level. On post exposure days of 14, there was no significant difference in the average amplitude of ERG (flash, cone, rod) between the exposed and normal control.
Conclusions: :
Photic damage of photoreceptor outer segment after LED exposure appeared reversible in OCT and ERG.
Keywords: photoreceptors • electroretinography: non-clinical • imaging/image analysis: non-clinical