gms | German Medical Science

Artificial Vision 2013

The International Symposium on Visual Prosthetics

08.11. - 09.11.2013, Aachen

Towards bidirectional retinal stimulators

Meeting Abstract

Search Medline for

  • Peter Walter - Department of Ophthalmology, RWTH Aachen University, Aachen, Germany

Artificial Vision 2013. Aachen, 08.-09.11.2013. Düsseldorf: German Medical Science GMS Publishing House; 2014. Doc13artvis33

doi: 10.3205/13artvis33, urn:nbn:de:0183-13artvis332

Published: February 13, 2014

© 2014 Walter.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Objective: To describe the concept of bidirectional retinal stimulators for improving the efficacy of prosthetic devices for the visual system.

Materials and Methods: Limitations of current available retinal stimulators and the underlying concepts were analyzed. Recordings of spontaneous local electrical activity were performed in several rodent models of Retinitis pigmentosa. Stimulation experiments were performed to test the hypothesis if the pattern of intrinsic retinal activity contribute to the likelihood of successful retinal stimulation.

Results: Different types of intrinsic activity can be found in the degenerated retina. The type of intrinsic activity effects the efficacy of stimulation considerably. Based on these findings a concept of bidirectional retinal stimulators is introduced.

Discussion: To increase the efficacy of successful retinal stimulation a bidirectional approach to retinal stimulation is suggested where implanted devices are equipped with signal recording and data analysis power. Thus, information on intrinsic retinal activity and the responsiveness to test stimuli can be used to automatically adjust the stimulation parameters and the pulse sequences.

Acknowledgements: This work was supported by DFG grant PAK 469/1, WA 1472/6.1, and a grant of the Hans Lamers Foundation, Jülich, Germany.