A device consisting of image-processing goggles and silicon chips implanted in the retina, could one day restore sight to the blind.
According to the Centers for Disease Control and Prevention (CDC), age-related macular degeneration (AMD) “is the leading cause of vision loss and blindness for Americans aged 65 years and older.”
The new system, which has been development for over a decade, can replace light-sensitive cells.
“We published the first concept paper of how we would approach this 12 years ago, and now we’ve validated in human patients basically all the key assumptions we made on the way,” says Daniel Palanker, professor of ophthalmology at Stanford University, and leader of the research.
Palanker decided to pursue an optical design approach. The system starts with special goggles that convert ambient light into invisible infrared images. The goggles would then project those images into the eye.
Photovoltaic sensors would be placed underneath the damaged part of a patient’s retina, and essentially replace the function of rods and cones within the eye. The implants collect the infrared images and convert them into electrical signals.
The miniaturized photovoltaic sensors also allow the patient to utilize the undamaged regions of the retina to see normally.
“I thought that the eye is a beautiful optical system, where information and power can be delivered by light, and this would eliminate the need for wires and make surgery much less invasive,” says Palanker.
Feasibility studies are well underway with an ongoing five-person trial in Paris, and a second trial in the Eastern United States slated for later this year.
There are still design improvements ahead for the research team. Currently, the device’s resolution reaches only 20/200 vision. Palanker is aiming for 20/40—the requirement for a driver’s license.
