Restoring vision with electronic photoreceptors : from Petri dish to patients and back
Abstract/Contents
- Abstract
- Treatments of neurological diseases using electro-neural interfaces are rapidly advancing. Inspired by the deep brain stimulators for Parkinson's patients and by cochlear implants for the deaf, we developed a photovoltaic subretinal prosthesis for restoring vision to patients blinded by retinal degeneration. Our "electronic photoreceptors" replace the function of the natural photoreceptors lost due to age-related macular degeneration. This is an array of photovoltaic pixels that convert incident light into electric current to convey the visual information to the secondary neurons in the retina by electrical stimulation. Images captured by a camera on augmented-reality glasses are projected onto the subretinal photovoltaic implant using pulsed near-infrared light. Patients with such prosthesis can read with acuity closely matching the pixel size of the implant currently used in a clinical trial (100 um), corresponding to 20/460 to 20/550 vision. This work presents the interaction between electronic photoreceptors and the retina, describing the properties of prosthetic vision in preclinical studies and in clinical trials, while informing future prosthesis design. In this thesis, We first explore the characteristics of the retinal response to pulsated electrical stimulation, focusing on the retinal neural code and features of natural retinal signal processing preserved in network-mediated retinal stimulation. We then describe how performance of visual tasks with pixelated images improve with resolution and contrast. Afterwards, we describe the results of behavioral and in vivo electrophysiological studies in rodents demonstrating the contrast sensitivity and visual acuity achievable with various configurations of subretinal implants. Finally, we conclude with the outlook into the ultimate limits of resolution and our progress toward scaling pixel size down to cellular dimensions.
Description
| Type of resource | text |
|---|---|
| Form | electronic resource; remote; computer; online resource |
| Extent | 1 online resource. |
| Place | California |
| Place | [Stanford, California] |
| Publisher | [Stanford University] |
| Copyright date | 2020; ©2020 |
| Publication date | 2020; 2020 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Author | Ho, Chung Yau Elton |
|---|---|
| Degree supervisor | Palanker, Daniel |
| Thesis advisor | Palanker, Daniel |
| Thesis advisor | Doniach, S |
| Thesis advisor | Fisher, Daniel S |
| Degree committee member | Doniach, S |
| Degree committee member | Fisher, Daniel S |
| Associated with | Stanford University, Department of Physics |
Subjects
| Genre | Theses |
|---|---|
| Genre | Text |
Bibliographic information
| Statement of responsibility | Elton Ho. |
|---|---|
| Note | Submitted to the Department of Physics. |
| Thesis | Thesis Ph.D. Stanford University 2020. |
| Location | electronic resource |
Access conditions
- Copyright
- © 2020 by Chung Yau Elton Ho
- License
- This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).
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