The effect of the locations of reference electrodes on the electrical evoked potentials elicited by suprachoroidal-transretinal stimulation in rabbit eye.

Abstract

 

Purpose

 

To determine the effect of the locations of reference electrodes on the electrical evoked potentials (EEPs) elicited by suprachoroidal-transretinal stimulation (STS) in rabbit eye.

 

Methods

 

A scleral pocket (3x5 mm) was created just over the visual streak in anesthetized rabbits (weight, 2.2-2.5 kg). The STS stimulating electrode system was implanted into the pocket. Three reference electrodes were implanted in the three different locations (the vitreous cavity; Group A, the sclera opposite to the stimulating electrode; Group B, and the sclera near the stimulating electrode; Group C) . EEPs were then elicited by each location of reference electrodes. Three sessions were repeated for each condition.

 

Results

 

The implicit times of the EEPs were 25.4±0.3 ms (Group A), 24.2±0.6 ms (Group B), and 26.5±5.4 ms (Group C) , and the amplitudes were 48.2±15.6 µV (Group A), 21.0±5.9 µV(Group B) and 12.7±6.4 µV(Group C) respectively. These differences in implicit time of EEPs were not significant (P>0.05). The amplitude of the EEPs in Group A was significantly larger the those of the other two Groups (P<0.001).

 

Conclusions

 

The reference electrode in the vitreous cavity seems to be most effective in suprachoroidal-transretinal stimulation.

 

 

 

Keywords: 688 retina • 508 electrophysiology: non-clinical • 755 visual cortex