Abstract
Purpose :
Flicker-induced retinal stimulation has been found to increase the retinal blood flow in response to increased metabolic demands of activated retinal neurons, but the influence of flickering light exposure on full-field electroretinogram (ffERG) is still unclear. The purpose of this study was to investigate the physiological changes of retinal response by ffERG after brief flickering light stimulation.
Methods :
Nine anaesthetized C57BL/6J mice (10 week-old) were light adapted at 1 cd/m2 for 10 minutes. After light adaptation, baseline ffERG (pre-flickering) was recorded and then was followed by 60 seconds of resting period to eliminate the aftereffect of light flashes. After resting period, the tested eye was stimulated by 8-Hz flickering light with 0.20 cd.s/m2 for 60 seconds that was immediately followed by post-flickering ffERG recording. Amplitudes and implicit times of ERG responses measured before and after flickering light stimulation were compared by paired t-test.
Results :
Retinal flickering light stimulation induced a significant increase in b-wave amplitude (pre-flickering amplitude=170.50±11.38μV; post-flickering amplitude=187.79±12.37μV; percentage change=10.42%±5.71%, p<0.001). However, there was no significant change in b-wave implicit time (pre-flickering implicit time=55.76±3.14ms; post-flickering implicit time=54.33±3.23ms; percentage change=-2.50%±7.18%, p>0.05), a-wave amplitude (pre-flickering amplitude=-43.50±7.07μV; post-flickering amplitude=-36.95±6.51μV; percentage change=-11.91%±56.37%, p>0.05) and a-wave implicit time (pre-flickering implicit time=22.08±1.11ms; post-flickering implicit time=21.87±1.21ms; percentage change=-1.12%±6.13%, p>0.05).
Conclusions :
Flickering light stimulation on retina led to a significant increase in ERG responses originating from middle retinal layer, primarily from bipolar cells but did not have significant effect on responses originating from photoreceptors. Further studies are required to understand the mechanism underlying enhanced ERG responses related to flicker-induced hyperemia.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.