Electronic eye implant surgery has restored sight to two blind men with a genetic eye condition, in a landmark medical breakthrough.
The operations, which took eight hours each, involved light-sensitive microchips, designed to mimic the eye's natural light-processing abilities, being implanted in the back of the men's retina, reported the UK’s Daily Telegraph.
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Surgeons at King's College Hospital, London, where the operations were conducted, confirmed the men had regained "useful sight" a few short weeks after the surgery, and are now able to distinguish black from white, as well as the silhouettes of objects.
"Since switching on the device, I am able to detect light and distinguish the outlines of certain objects which is an encouraging sign," said Robin Millar, 60, who is one of the recipients of the surgery.
"I have even dreamt in very vivid colour for the first time in 25 years so a part of my brain which had gone to sleep has woken up.
"I feel this is incredibly promising for future research and I'm happy to be contributing to this legacy."
The men both possess a form of blindness known as retinitis pigmentosa (RP), a degenerative condition inherited from birth. It is estimated that one in every 3,000 children are born with RP in Australia.
The microchip developed by Retina Implant AG differs from other implants, in that it works in conjunction with the eye itself, rather than being dependant on external cameras to absorb and transmit light.
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"You can think of the retina as the film in the back of a camera," explained Dr Tim Jackson, one of the trial leaders and a consultant retinal surgeon at the hospital.
"That has died away but the remaining connections are still intact and we can use these to transmit a signal to the brain. The chip replicates the action of the cells that have died away."
Although Jackson says the men's vision is still an approximation of vision, he hopes that their sight will continue to improve as their brains "relearn" to focus naturally with the help of the implant.
"The patients can see fairly basic shapes and distinguish a white plate on a dark table," he said.
"The vision they have is not the same as what they had before they lost it," he said. "They see flashes of light in the shape of an object and they have to translate that into an image.
"The patients can see fairly basic shapes and distinguish a white plate on a dark table, for example. It may be that with time their vision becomes more refined because the brain has to relearn how to see."
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Doctors are hopeful that the technology will be adaptable to treat other eye conditions, including macular degenerative disease, the leading cause of blindness in Australia affecting one in seven people over the age of 50.
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