Abstract
Purpose :
The transcorneal electrical stimulation (TES) is usually performed as a preoperative examination for the purpose of patient selection for Suprachoroidal-Transretinal Stimulation (STS) type retinal prosthesis. The purpose of this study is to evaluate the safety of TES.
Methods :
Three rabbits were used in the present study. Custom-designed ERG electrode (Mayo Co., Japan) is comprised of two platinum rings (diameter, 13 mm and 17mm). The smaller ring and larger ring were used as stimulating and return electrode respectively. The electrode was put on the corneal surface. Anodic-first charge-balanced biphasic pulses (10 ms/phase and 20 pulses/s of pulse frequency) were applied to the cornea. The stimulus intensity was 2.6 mA, which was 30% higher than the maximum intensity of ordinary TES examination. We then applied continuous stimulation for 300 seconds, which was 10 times longer in comparison to ordinary TES examination. Slit-lamp examination was performed just before the stimulation and 1 hour, 3 days, and 7 days after stimulation. We then enucleated the eyeballs and conducted histological examination by HE staining.
Results :
We did not observe any significant change in cornea or conjunctiva through the slit-lamp examination at all time intervals after the stimulation in all three animals. Moreover, histological examination did not reveal any corneal damage.
Conclusions :
These results indicated that there was little possibility of corneal or conjunctival damage by TES examination. Therefore, it could be concluded that TES examination is safe.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.