Intraocular impedance as a function of the position in the eye, electrode material and electrode size

Samip Shah; Amy Chu; David Zhou; Robert Greenberg; Dilek Guven; Mark S Humayun; James D Weiland

doi:10.1109/IEMBS.2004.1404163

Intraocular impedance as a function of the position in the eye, electrode material and electrode size

Conf Proc IEEE Eng Med Biol Soc. 2004:2004:4169-71. doi: 10.1109/IEMBS.2004.1404163.

Authors

Samip Shah¹, Amy Chu, David Zhou, Robert Greenberg, Dilek Guven, Mark S Humayun, James D Weiland

Affiliation

¹ Department of Electrical Engineering, University of Southern California, Los Angeles, CA, USA.

PMID: 17271221
DOI: 10.1109/IEMBS.2004.1404163

Abstract

A critical element of a retinal prosthesis is the electrode assembly, which is placed on the retina. It is via this interface that the nerve cells are stimulated to produce the perception of light. The electrode impedance is an integral part in determining the design of the stimulating electrode and the attached circuit. The impedances involved are not only the tissue impedance but the electrode itself contributes to the impedance. Further on the electrode impedance depends not only the material of the electrode but also the size of the electrode. This paper discusses the results obtained by the intraocular impedance measurements with varying electrode size, electrode material and position of the electrode within the eye.