Retinal degeneration leads to blindness due to loss of photoreceptors, but the inner retinal neurons are preserved to a large extent. Electrical stimulation of these neurons enables reintroduction of visual information into the nervous system, and hence may allow restoration of sight. Two distinct approaches to this challenge are being developed:
- Electronic substitute for photoreceptors: replacement of the lost photoreceptors with a subretinal implant, with a goal of stimulating the secondary neurons in the retina – primarily the bipolar cells, and relying on transmission of their outputs to the amacrine and ganglion cells, which convert these inputs into the patterns of action potentials propagating to the brain. This approach may benefit from retaining some of the natural retinal signal processing, but it relies on preservation of the neural network, which may be limited in advanced degeneration.
- Artificial retina: epiretinal implants for direct stimulation of the ganglion cells, with a goal of directly encoding the visual information captured by a camera into the proper sequence of spikes in the RGCs of each type. This approach does not rely as much on preservation of the retinal neural network, and hence may be applicable in more advanced stages on retinal degeneration, but it requires identification of various cell types and their selective stimulation.
This conference will consist of two sessions highlighting state-of-the-art approaches of both kinds.
We had a great symposium, thank you all for participating!
ABSTRACTS & RECORDINGS NOW AVAILABLE... links below
Long-Sheng Fan Iridium Medical Technology Company, Taiwan
In-vivo characterization of the individual electrode-retina interface impedance: the physical firing process of the HARP4k subretinal implant
Jia-Yi Zhang Fudan University, China
Titanium oxide nanowire as artificial photoreceptors - recent progress in retinal physiology and behavioral experiments
Eric Glowacki Linkoping University, Sweden
Ultrathin organic photocapacitors for neuromodulation
Paul Werginz Vienna University of Technology, Austria
Kinetics of the bipolar cell response to electrical stimulation: computational modeling
Gunther Zeck University of Tuebingen, Germany
In search for optimal stimuli
Yossi Mandel Bar Ilan University, Israel
Cortical responses to subretinal stimulation are affected by the adaptive state in the surrounding healthy retina
Daniel Palanker Stanford University, USA
Photovoltaic replacement of photoreceptors in geographic atrophy
Maesoon Im Korea Institute of Science and Technology, Korea
Understanding properties of network-mediated responses elicited by epiretinal stimulation
Diego Ghezzi Ecole Polytechnique Federale de Lausanne, Switzerland
Results ex-vivo and in-vivo with the POLYRETINA device
Ethan Cohen US Food and Drug Administration
The microglia layers response to electrical overstimulation of the retina imaged under epiretinal stimulus electrodes
Rejean Fontaine Universite de Sherbrook, Canada
Design and assembly considerations for an optical data and power link-based retinal implant
Daniel Rathbun Henry Ford Health System, USA
MEA-based classification of retinal ganglion cells for bionic vision
Dante Muratore Stanford, USA
Design of a cell-type specific bi-directional electrical interface for artificial retinas
