April 2011
Volume 52, Issue 14
Free
ARVO Annual Meeting Abstract  |   April 2011
Efficacy of Electrode Return Configuration in a Suprachoroidal Retinal Prosthesis
Author Affiliations & Notes
  • Rosemary Cicione
    The Bionic Ear Institute, East Melbourne, Australia
    Department of Electronic Engineering, La Trobe University, Melbourne, Australia
  • Mohit N. Shivdasani
    The Bionic Ear Institute, East Melbourne, Australia
  • James B. Fallon
    The Bionic Ear Institute, East Melbourne, Australia
  • Chi D. Luu
    Macular Research Unit, Centre for Eye Research Australia, East Melbourne, Australia
  • Penny J. Allen
    Macular Research Unit, Centre for Eye Research Australia, East Melbourne, Australia
  • Graeme Rathbone
    The Bionic Ear Institute, East Melbourne, Australia
    Department of Electronic Engineering, La Trobe University, Melbourne, Australia
  • Chris E. Williams
    The Bionic Ear Institute, East Melbourne, Australia
  • Footnotes
    Commercial Relationships  Rosemary Cicione, None; Mohit N. Shivdasani, None; James B. Fallon, None; Chi D. Luu, None; Penny J. Allen, None; Graeme Rathbone, None; Chris E. Williams, None
  • Footnotes
    Support  This research was funded by a grant from the Australian Research Council to Bionic Vision Australia
Investigative Ophthalmology & Visual Science April 2011, Vol.52, 4961. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Rosemary Cicione, Mohit N. Shivdasani, James B. Fallon, Chi D. Luu, Penny J. Allen, Graeme Rathbone, Chris E. Williams; Efficacy of Electrode Return Configuration in a Suprachoroidal Retinal Prosthesis. Invest. Ophthalmol. Vis. Sci. 2011;52(14):4961.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract
 
Purpose:
 

To determine the effect of electrode return configuration on charge threshold and spatial selectivity in suprachoroidal electrical stimulation of the retina.

 
Methods:
 

A flexible polyimide substrate electrode array was inserted into the suprachoroidal space of normally-sighted, anesthetized cats (n=5). Individual electrodes on the array were electrically stimulated in three return configurations: monopolar (MP, return electrode in vitreous humour), common ground (CG, all remaining electrodes used as return) and hexagonal (HX, six electrodes surrounding active used as return) while recording multiunit activity from the visual cortex. For each retinal electrode stimulated, a best cortical site, defined as the recording site in the visual cortex with the lowest threshold was found. Spike rate at suprathreshold charge levels (normalized to that of the best cortical site) was determined across the cortex in order to ascertain the spatial selectivity of each return configuration.

 
Results:
 

Charge threshold of MP stimulation was significantly lower than that of both CG and HX configurations (Fig. 1A, *, p<0.05). There was no significant difference in spatial selectivity among the three return configurations.

 
Conclusions:
 

MP electrode return stimulation is the most charge efficient in a suprachoroidal retinal prosthesis. Electrode return configuration has little influence on spatial selectivity.  

 
Keywords: retina • visual cortex • electrophysiology: non-clinical 
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×