"Without the glasses you can't see a thing, put the glasses on you can suddenly see. You get that wow factor every time you do it."
Philip Booth, 60, has had bionic eyes for the last three and a half years. He suffers from the degenerative condition retinitis pigmentosa (RP), an inheritable disease where the rods and cones in his retina slowly stop working. He first began losing his sight at age seven, and by the age of 30 he was completely blind. However, he can now see again -- thanks to the Argus II, an implant that gives him a new kind of sight.
Last month it was approved by the US Food and Drug Administration (FDA) for public use, and a paper published this month in the British Journal of Otphamology has shown that the system can not only give people a basic form a sight back, but can also, in some cases, even help them read.
The Argus II has been undergoing trials since 2008, and in 2010 Wired.co.uk covered it on the eve of being approved in mainland European countries such as Germany and Italy. It works by taking over the role of generating electrical signals from the redundant retina, with an implant sending pulses down the optical nerve that the brain can learn to interpret as vision. It's nothing like vision we'd recognise, though -- instead, it's very abstract, often no more than pulses or flashes of light.
Booth is one of those who signed up to test the technology, having the operation to have it installed in March 2009. "It's not vision as I remember it. I can see flashes of light, if I focus on an object it'll appear as a flash of light to me," he told Wired.co.uk. "I can identify that object and where it is. I can see where windows are, where doors are. I can see clothing, the difference between a white shirt and a black shirt if there's a contrast. I'm signed up for another 12 months and hopefully it'll be extended beyond that. I would tell anyone else who gets the chance to do this to do it."
While Booth hasn't been able to read with his implant, retinal surgeon and specialist Lyndon da Cruz told Wired.co.uk that 23 out of the 30 people tested "could read large letters, and four of them could read small letters, by which I mean three to five centimetres high, which for a totally blind person is an extraordinary phenomenon".
Da Cruz has been a part of the trials at Moorfields Eye Hospital in London, one of several locations around the world where tests have been taking place to test the Argus II implants since 2008.
They've found that "these devices are working for a long period of time and are very stable, up to four years on average with some people up to six years". "[The Argus II] has two broad components," he explains. "There's the external component -- a pair of Oakley sunglasses with a tiny camera built into the bridge attached to a small computer. The camera picks up whatever you're looking at and the computer turns it into a pixelated picture and transmits that picture into a device in the eye. The device in the eye consists of a receiver and an electrode panel that stimulates the eye with the same pattern.
The image is transmitted wirelessly. You put the sunglasses away and you look normal, nobody can see the device in the eye."
The transmitter has a range of perhaps one or two centimetres, and the system as a whole has a cost in the range of around $100,000 (£66,000), though da Cruz adds that with follow-up training and other clinics added on the cost is in the ballpark of between £80,000 and £100,000 (though that cost is being reduced as development continues). The surgery, which takes between two to five hours, isn't too complicated either. "The steps are within the capabilities of a reasonably well-practiced retinal surgeon," da Cruz said.
He continued: "We explain to patients that it won't be anything like the vision that they lost. It won't be some blurry or grainy version of what they had. The form they describe is the object being made up of light streaks or dots of light that are somewhere in space, because it's difficult, you don't have context. You see the objects, you see the light form a shape, sort of where you're looking at is where they are. You don't know how far away they are."
However, it's a system that only works with certain kinds of blindness. Da Cruz said: "It hasn't been trialled with other kinds of blindness, but that's not to say it can't be applied to them.
You definitely need an optic nerve, so this excludes the huge number of people who are blind from glaucoma or from trauma severing the optic nerve, or from optic nerve disorders. That's one large group this device will never help, because there's no connection between the artifical retina and the brain."
Moorfields is one of 11 centres around the world Da Cruz said: "Moorfields has been central in that it has the research, the surgical skills and the multidisciplinary people to be able to run this sort of trial and generate large numbers of patients from a rare group, because it has a large collection area for inherited retinal diseases. It's good that a big American project came to Europe and Moorfields was very good to offer that, and with the NHS in the UK we were able to do a third of the cases in the trial."
The early stages of the trial were focused on the initial surgery and then making sure the Argus II was stable and worked fine through the tests the doctors had devised. The paper published this month in the British Journal of Opthalmology shows the "core nature" of the device's capabilities, da Cruz explains. "There's a huge range of functions. We're to work out how much they can see on a screen, how much they can see in real life, and there's been a big argument over whether these sorts of tests on screens in a relatively artificial environment reflect in any way the real world or not. We're now looking at tests that have a real-world component and a lab component to see what the connection is, and whether we need to go out, as we're doing more and more, and do rehabilitative work in the person's home."
He continues: "It's a shame it's so late that we're looking at going into people's environments. It's quite a slow process, everything is regulated, so it's fairly cumbersome to push on. We don't want to turn our patient's lives into a total experiment for the device. So they sometimes deal with us once a week for years. That's an enormous commitment, that's a seventh of your life, to which we're very grateful."
Wired.co.uk covered a rival Australian bionic implant in September 2012.
Like the Argus II, the system from Bionic Vision Australia places electrode implants in the eye. However, it is still in the prototype stage, though it boasts 1,024 electrodes compared to the Argus II's current 60, so its final vision may be clearer when it eventually comes to market. That is likely to be several years from now, though.
The Argus II currently has a very focused visual field, and further development will focus on giving people a bigger area of sight. Da Cruz said: "Because we can get a reasonable amount of definition from the pixel density we have now, it's important to give people a bigger visual field than to give them sharper vision in a smaller area. Then later on, we'll increase density as well as field."
But will it ever match natural vision? "We'd like to think it'll be pretty good," da Cruz said. "I think to recreate the retina, and the quality of vision that gives you, artificially, is quite a task for all sorts of biologically limiting reasons. But I think it encourages us is that there will be a device that is stable and safe, which will react with the eye without the eye rejecting it, and which will have better definition than we have now over a bigger area. I think that will be more immediately useful for people over more of the time. Making something that is a perfect copy of normal vision, we just don't have the materials or the technology to do that now. But's it's a nice place to aim."
The Argus II is already available in several countries in Europe, having been approved in April 2011 for the national health services in Germany, Italy and France. In the United States, approval came two weeks ago. Da Cruz explains that the National Institute for Clinical Health and Excellence (Nice) is currently evaluating its suitability for the NHS, so the Argus II has only been given to private patients so far.
This article was originally published by WIRED UK
