Retinal implants hold great promise for people with severe vision impairment including blindness. We’ve covered several retinal implant technology developments. For example, Oxford University’s Department of Chemistry created biological synthetic soft tissue that could be used to create replacement retinas. Nano Retina’s digital chip implant is coated with tiny nano-technology light sensors and paired with special glasses that control the chip.
The École polytechnique fédérale de Lausanne (EPFL) is a university and research institute in Lausanne, Switzerland. EPFL School of Engineering researchers recently published a study in Nature Communications that documents their progress and findings developing new retinal implant technology. The team’s primary goal is to develop a retinal implant that covers a visual field of at least 40 degrees. According to EPFL, the retinal implants available today employ electrodes to stimulate retinal cells, require a wired connection, and have a maximum of 20 degrees of visual field.
EPFL’s retinal implant breaks ground in several aspects. The implant uses photovoltaic pixels instead of electrodes to stimulate retinal cells. The photovoltaic pixels generate current independently, eliminating any need for an external energy source, so there are no wires. The photovoltaic pixels use much less space than electrodes, so more pixels can fit on the implant, adding to visual acuity and field of vision. The EPFL team built the implant with an extremely flexible material. Due to its flexibility, the researchers were able to fold the implant which reduces the size of the incision on the eyeball to insert the device. This also supports much larger devices than conventional implants.
The EPFL researchers found during testing that the implant prototype increased visual field and visual acuity and also proved to be non-toxic. Next steps include observations on how well humans adapt to seeing with the new implants, testing how long the implant lasts, and exploring additional ways the pixels function. The team expects a final version will give wearers a 46-degree visual field.
The EPFL’s retinal implant is interesting and exciting. The implant is interesting because it uses photovoltaic pixels instead of electrodes. The pixels enable wireless operation without other external source and make space for higher resolution images. The implant shines light on a path to restored vision for people who were otherwise — literally — left in the dark.
