Scottish scientists are developing an electronic implant that will be capable of curing two of the most common forms of blindness.
Dr Keith Mathieson, from Glasgow University’s Department of Physics, is using digital camera technology to create the ‘bionic eye’.
He has developed a microchip that can replicate the role played by the retina, the sensitive lining at the back of the eye that converts light into a signal that is sent to the brain.
The implant would allow doctors to restore the sight of more than 800,000 people in the UK.
Mathieson has already developed the first prototype of the implant that can turn images into electrical signals.
The early chip has a definition of just 74 pixels but is able to send electronic messages representing basic shapes to eye cells linked to the brain.
But Mathieson warned it could be at least five years before they are ready to make the first implant for humans. He said: “We are trying to fool the retina into thinking it has received a signal by replacing the light-detecting cells with a small imaging detector.
“Blindness, especially when it happens in later life, is a debilitating condition. To be able to restore people’s quality of life would be life-changing.”
Mathieson has been awarded £116,000 by the Royal Society of Edinburgh to develop the implant, which would be used to treat diseases such as age-related macular degeneration, a condition that affects around 800,000 elderly people.
It could also be used to cure retinitis pigmentosa, where the peripheral vision deteriorates early in life. Around 15,000 people suffer from the disease, and whole families can be affected.
The implant uses minute image detectors found in digital cameras to turn light into electrical signals, mimicking the function of retina cells. Attached to an array of tiny electrodes, the signals from the detector are sent to undamaged retina cells, which then send the information to the optic nerve and on to the brain.
Up until now, Mathieson’s team have been testing their chips on retinal tissue grown in the laboratory. But they believe they have found a way of interfacing them with the biological tissue of the eye.
Using microchips in the eye also opens up many other possibilities. Mathieson said: “We are hoping to use smart chips to compress this information in the same way the retinal cells do.
“It would be possible not just to detect the visible spectrum but also ultraviolet and infra-red light. If we put memory into the chip, we could also have action replay and slow motion.”
But he said the main purpose of the project was to find ways of restoring normal sight.
The team now hope to increase the number of pixels the prototype can handle.
Mathieson said: “At around 500 pixels we are getting to the point where people could walk down the street or even recognise faces.”
Professor John Coggins, vice president of the Royal Society of Edinburgh, said: “There is a real quality of life issue at stake here. We must be looking at doing something fundamentally better for blind people.
“It may be another 20 years or so before we see people actually being treated with this, but in a few years we might see a volunteer actually trying it out.
“Without researchers looking at improving healthcare technology, these advances will never take place.”
John Legg, director of the Royal National Institute for the Blind Scotland, welcomed the research.
He said: “Although this research is at an early stage it is encouraging to know that scientists are looking at ways of applying the latest technology to alleviating the loss of sight.”