Electrical stimulation with a needle-type electrode inserted into the optic nerve in rabbit eyes.
OBJECTIVE
To investigate whether electrical stimulation of the optic nerve can elicit an electrical evoked potential (EEP) in rabbits and to determine whether such stimulation is a useful approach for the placement of a visual prosthesis.


METHODS
Two needle-type electrodes were inserted into the optic nerve using a transvitreal approach. For electrical stimulation, monophasic and biphasic pulses were used. By stimulating the optic nerve, the EEP was elicited. After evaluation of the EEP, a histological study was carried out.


RESULTS
When electrical stimulation was applied, the EEP could be recorded. The threshold with monophasic and biphasic stimulation was 10 +/- 0 microA and 20 +/- 8.2 microA, respectively. Histological examination revealed no major complications, such as bleeding or degeneration, which might have resulted from the insertion of electrodes or the electrical stimulation.


CONCLUSIONS
Electrical stimulation of the optic nerve can elicit an EEP, suggesting that this approach may be useful for a visual prosthesis system.
Sakaguchi
Hirokazu
H
Department of Ophthalmology, Graduate School of Medicine, Osaka University, Suita 565-0871, Japan. sakaguh@ophthal.med.osaka-u.ac.jp
Fujikado
Takashi
T
Kanda
Hiroyuki
H
Osanai
Makoto
M
Fang
Xiaoyun
X
Nakauchi
Kazuaki
K
Ikuno
Yasushi
Y
Kamei
Motohiro
M
Ohji
Masahito
M
Yagi
Tetsuya
T
Tano
Yasuo
Y
D000818:Animals; D004558:Electric Stimulation / Q000379:methods*; D004567:Electrodes, Implanted / Q000009:adverse effects; D005074:Evoked Potentials, Visual / Q000502:physiology*; D009339:Needles; D009900:Optic Nerve / Q000473:pathology / Q000502:physiology*; D011817:Rabbits; D014793:Visual Cortex / Q000502:physiology