The Bionic Eye: A Second Chance at Sight
Over 285 million people in the world suffer from vision loss and blindness. The retna of the eye is like a camera, if this is damaged, the brain cannot process any images coming through the eye which is what vision is.
But now scientists and researchers are working to make advances in ophthalmology, one of which is the bionic eye.
The Argus II Retinal Prosthesis System is the world's first FDA approved device, designed to restore vision to those suffering from a specific type of blindness called Retinitis Pigmentosa, that about 1 in 4,000 Americans suffer from.
Breaking Down the Bionic Eye
The bionic eye is comprised of two different parts. Glasses with a mounted video camera capture images and transmit them to a surgical implant in the eye.
This process begins with embedding a tiny wafer-like computer chip (electrodes) in the back of the eye, on the patient's retna. He or she then wears glasses with a video camera that captures the images. These images are them signaled to a video processing unit worn on the body. The electrodes impulse wirelessly and signals the brain, allowing it to decipher between light and dark. The bionic eye implant sends light wave signals to the optic nerve, bypassing the damaged retina.
The 100-millimeter-square chip sits behind the retina, the part of the eye that contains the photoreceptor cells that respond to the light of the world by triggering electric pulses in other cells. Those pulses are part of a chain reaction that sends information up the optic nerve to the brain. In certain retinal diseases, the photoreceptor cells die off, but the remaining relay cells are undamaged. Different visual prostheses target different cells within this system for electrical stimulation.
Not Normal Vision but an Upgrade
From here, patients are able to make out shapes, forms and outlines in intermittent flashes. Everything is in black and white now, but with training and periodic upgrades over a five-year period doctors are confident patients will gradually improve their vision with exercises and therapies.
It’s not a substitute eye, but it literally brings light to the blind — or at least those who have a condition called retinitis pigmentosa, where vision gradually recedes but the retina is left intact.
It's hard to tell what type of vision the patient can see. It's impossible to evaluate the exact type of vision they get back right away. They won't be able to recognize faces or read books necessarily, but they do get a pix-elated image, allowing them to make better sense of their surroundings.
Future of Sight is Visionary
No one really know if there are possible side effects from the devices' electrical stimulation over long-term use but it seems that these devices are a glimpse at the future of vision. Many companies are working to improve this technology even beyond its current capabilities.
Second Sight, the company that got FDA approval for the first visual prosthesis in 2013, currently offers patients about 20/1300 vision. The German company Retinal AG, whose system has been approved by European regulators, offers about 20/500.
Australia’s Bionic Vision is planning a clinical trial of its technology in the next year, said researcher Nigel Lovell at the Neural Engineering meeting. Experts have emphasized that there is a need to study the code of electric pulses by which the eye’s cells transmit information, in hopes of dramatically improving the crude vision produced by current prosthetic devices.