A “bionic eye” may one day help blind people see again, according to US researchers who have successfully tested the system in rats.
The eye implant – a 3-millimetre-wide chip that would fit behind the retina – could be a dramatic step above currently available technology, says the team at Stanford University, California, US.
About 1.5 million people worldwide have a disease called retinitis pigmentosa, and 700,000 people in the western world are diagnosed with age-related macular degeneration each year. In both degenerative diseases, retinal cells at the back of the eye that process light gradually die.
Groups at the University of Southern California and the University of Illinois at Chicago Medical Center, both in the US, have developed retinal implants for humans to improve these conditions. But Daniel Palanker, a physicist at Stanford working on the bionic eye, says these implants have very low resolution.
“Basically, [that work is] a proof of principle,” Palanker says. He claims his system has higher resolution.
A visual acuity of 20/20 is considered normal, while 20/400 is considered blind. Palanker and his team say their device could provide acuity of 20/80. “With 20/80 vision you can certainly read large forms and live independently,” Palanker says. “It’s a huge step forward.”