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Contacts Claim to Fix Your Vision While You Sleep

DiscoblogBy Allison BondJuly 8, 2009 9:29 PM


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Many of us with less-than-perfect vision fantasize about waking up one morning able to see perfectly. Wish no more: There are contact lenses that claim to shape the lens of your eye while you sleep, eventually giving nearsighted people perfect vision (a remedy that's significantly less sci-fi than a telescope implanted in the eye). Nearsightedness occurs when the eye focuses light in front of the membrane at the back of the eye called the retina, instead of on it, usually due to an elongated eyeball. The eyeglasses or contacts that combat this condition work by diverging incoming light, which is then converged by the wearer's eye. The corrective contacts, called i-GO Overnight Vision Correction, reportedly work by gently reshaping your eye's lens. A columnist in

The Guardian

wrote about his experience trying them out:

I begin with a sight test, then [optician Kieran] Minshull takes a topography of my eye, photographing the curvature of my cornea to obtain the measurements needed to make the lenses.... These lenses, I am told, do not usually work instantly. "We should achieve something like a 70% change within the first night of wear," says Minshull. In the early days, most users find their eyesight deteriorates by the end of the day. "You may notice a little bit of ghosting in the evening," he says. I am supplied with some -1.50 [prescription] daily disposable contact lenses in case my eyesight becomes less than perfect.... After two nights in the lenses, I wake up and - hosanna! - I can see. Without lenses. Almost perfectly. The problem is at night: when it gets dark, I realise that while I can read car numberplates at a distance, my sight is distorted by electric lights, which are almost as blurry as if I had my normal vision.... Minshull explains that this "ghosting" or halo effect occurs because, while the lenses have corrected the centre of my pupils, they have not yet altered the periphery. This means that in low light, when my pupils widen, I am seeing with the corrected zone and with a small uncorrected area. With most clients, this passes in time.

The contacts aren't a permanent fix: You need to wear them every night to maintain the new shape of your eye. And the idea of wearing contact lenses at night almost seems to defeat the purpose of not having to wear them during the day. Still, popping in a pair of contacts for the sake of clearer vision is less daunting than laser surgery. Related Content: Discoblog: Will the Laptops of the Future Be a Pair of Eye Glasses? Discoblog: Possible Cure For Blindness: Implanting a Telescope in Your Eye Discoblog: When Contacts Attack! Amoebas in Contact Lenses Cause Blindness

Image: flickr / schani

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