Share Email Print

Proceedings Paper

Optical imaging of the retina in response to the electrical stimulation
Author(s): Takashi Fujikado; Yoshitaka Okawa M.D.; Tomomitsu Miyoshi M.D.; Yoko Hirohara; Toshifumi Mihashi; Yasuo Tano M.D.
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Purposes: To determine if reflectance changes of the retina can be detected following electrical stimulation to the retina using a newly developed optical-imaging fundus camera. Methods: Eyes of cats were examined after pupil dilation. Retina was stimulated either focally by a ball-type electrode (BE) placed on the fenestrated sclera or diffusely using a ring-type electrode (RE) placed on the corneoscleral limbus. Electrical stimulation by biphasic pulse trains was applied for 4 seconds. Fundus images with near-infrared (800-880 nm) light were obtained between 2 seconds before and 20 seconds after the electrical stimulation (ES). A two-dimensional map of the reflectance changes (RCs) was constructed. The effect of Tetrodotoxin (TTX) was also investigated on RCs by ES using RE. Results: RCs were observed around the retinal locus where the stimulating electrodes were positioned (BE) or in the retina of the posterior pole (RE), in which the latency was about 0.5 to 1.0 sec and the peak time about 2 to 5 sec after the onset of ES. The intensity of the RCs increased with the increase of the stimulus current in both cases. RCs were completely suppressed after the injection of TTX. Conclusions: The functional changes of the retina either by focal or diffuse electrical stimulation were successfully detected by optical imaging of the retina. The contribution of retinal ganglion cells on RCs by ES was confirmed by TTX experiment. This method may be applied to the objective evaluation of the artificial retina.

Paper Details

Date Published: 11 February 2008
PDF: 8 pages
Proc. SPIE 6844, Ophthalmic Technologies XVIII, 68440H (11 February 2008); doi: 10.1117/12.776843
Show Author Affiliations
Takashi Fujikado, Osaka Univ. (Japan)
Yoshitaka Okawa M.D., Osaka Univ. (Japan)
Tomomitsu Miyoshi M.D., Osaka Univ. (Japan)
Yoko Hirohara, Topcon Research Institute (Japan)
Toshifumi Mihashi, Topcon Research Institute (Japan)
Yasuo Tano M.D., Osaka Univ. (Japan)

Published in SPIE Proceedings Vol. 6844:
Ophthalmic Technologies XVIII
Bruce E. Stuck; Fabrice Manns; Per G. Söderberg; Michael Belkin M.D.; Arthur Ho, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?