Photovoltaic retinal prosthesis: implant fabrication and performance
Lele Wang1, K Mathieson, T I Kamins
1Department of Electrical Engineering, Stanford University, Stanford, CA 94305, USA. lelewang@stanford.edu
Journal of Neural Engineering
|July 14, 2012
Summary
This study developed a wireless photovoltaic retinal prosthesis using a silicon photodiode array to restore sight for degenerative retinal diseases. The device efficiently stimulates retinal neurons with near-infrared light, simplifying implantation.
Area of Science:
- Biomedical Engineering
- Materials Science
- Ophthalmology
Background:
- Degenerative retinal diseases cause blindness.
- Current treatments have limitations.
- Retinal prostheses offer a potential solution.
Purpose of the Study:
- To develop and test a novel photovoltaic retinal prosthesis.
- To restore vision in patients with degenerative retinal diseases.
- To create a wireless, subretinal implantable device.
Main Methods:
- Fabrication of a silicon photodiode array using integrated-circuit/MEMS processes.
- Design of pixels with series-connected photodiodes for photovoltaic conversion.
- Use of near-infrared light for stimulation and iridium oxide for electrodes.
Main Results:
- The device successfully converts near-infrared light into bi-phasic current for neural stimulation.
- Photodiodes demonstrated efficient photo-responsivity and low dark current.
- The prosthesis elicited reliable retinal responses at safe light irradiances.
Conclusions:
- The developed photovoltaic retinal prosthesis enables wireless retinal stimulation.
- The device simplifies surgical implantation and offers improved resolution.
- This technology holds promise for restoring sight in patients with retinal degeneration.
