Alternative method in experimental ERG for retinal toxicity

Year 2018, Volume: 35 Issue: 2, 35 - 39, 25.10.2019

Volkan Yeter , Osman Sayın , Yüksel Süllü

Abstract

We aimed to define a cost-effective and alternative method for
experimental electroretinography (ERG) in rabbits. The trigger input port of
data acquisition device was connected to output port of an unemployed EEG
device. The exposure area of photic stimulator was firmly covered by Wratten
neutral density filters with variable optical densities(ODs). Different optical
transmissions were obtained by putting more than one filter over the other one.
The illumination of the area at the level of rabbit eye was measured by a
luminometer in photic stimulations. ERG was performed to the both eyes of three
albino rabbits in scotopic and photopic conditions at the baseline.
Intravitreal saline injections were performed in right eyes of the rabbits. ERG
and ophthalmologic examination were repeated one week later. ERG responses were
obtained by short-duration light stimuli with different strengths in scotopic
(-2.69; -1.69; 0.00; 0.30; 0.69; 0.90; 1.10; 1.30; 1.69; 2.00 log stimulus
energy (log cd.s/m²)) and in photopic conditions (1.3; 1.69; 2.0; 2.10; 2.30
log stimulus energy (log cd.s/m²)). Although minimal decays in amplitudes of a-
and b- waves were detected after saline injection, there was no significant
difference between baseline and after injection for the stimulus-response time
of a- and b- waves (p>0.05). An unemployed EEG device can be effectively
used for photic stimulation in experimental ERG in the studies of retinal
toxicity.

Keywords

Electroretinography, photic stimulator, electroencephelography

References

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