Design of a high-resolution optoelectronic retinal prosthesis

Area of Science:

• Biomedical Engineering
• Ophthalmology
• Neuroscience

Background:

• Electrical stimulation of the retina can induce visual percepts in patients with retinal degenerative diseases.
• Current retinal implants lack the resolution (thousands of pixels) necessary for functional vision restoration.

Purpose of the Study:

• To design a high-resolution optoelectronic retinal prosthetic system.
• To achieve a stimulating pixel density of up to 2500 pix mm(-2) for improved visual acuity.

Main Methods:

• Presented two sub-retinal implant geometries (perforated membranes, protruding electrode arrays) to ensure proximity of neural cells to electrodes.
• Developed a goggle-mounted system projecting infrared images onto the retina to activate an array of photodiodes.
• Enabled natural eye scanning and simultaneous use of remaining natural vision.

Main Results:

• The designed system achieves a stimulating pixel density of up to 2500 pix mm(-2), geometrically corresponding to a visual acuity of 20/80.
• Described proximity requirements between neural cells and stimulation electrodes for desired resolution.
• Demonstrated optical delivery of visual information for real-time image processing and flexible control of stimulation parameters.

Conclusions:

• The proposed optoelectronic retinal prosthetic system offers a pathway to significantly higher resolution than current implants.
• The design facilitates natural visual scanning and integrates with residual natural vision.
• This approach allows for advanced, adaptable image processing for retinal stimulation.