Photovoltaic Retinal Prosthesis for Restoring Sight to Patients Blinded by Retinal Injury or Degeneration
Abstract
Traumatic retinopathy and retinal degeneration lead to blindness due to loss of photoreceptors. Visual information can be reintroduced into the retina by patterned electrical stimulation of the remaining inner retinal neurons. Photovoltaic subretinal prosthesis directly converts light into pulsed electric current in each pixel, stimulating the nearby neurons. Images captured by the goggles-mounted camera are projected onto retina in augmented-reality goggles using pulsed near-infrared (~880nm) light. We prepared this technology for a clinical trial, including optimization of the photovoltaic array, addition of the biocompatible protective coating for long-term implantation, fabrication of the video goggles with a camera, and image processing software. After technology transfer to our partner company, Pixium Vision, the first clinical trial started in 2018. To date, 3 photovoltaic arrays of 2x2mm in size and 30m in thickness, with 100m pixels have been implanted in patients with geographic atrophy. All patients perceive white-yellow patterns with adjustable brightness, in retinotopically correct locations. Majority of them correctly differentiate simple objects and recognize patterns, such as bars at different orientations, with spatial resolution up to the limits of the implant. These results indicate that further development of smaller pixels should provide higher resolution and enable even more functional restoration of sight.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 2018
- Accession Number
- AD1055792
Entities
People
- Daniel Palanker
Organizations
- Stanford University