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An Implanted Macular Degeneration Telescope

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A week or so ago I wrote a post about a new treatment that doctors in the UK had discovered to help stop age-related macular degeneration – I just found another instance of technology fighting AMD, and it’s pretty cool.

Check this out:

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The company who invented this technology, VisionCare, has a really interesting description of the procedure on their site:

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The prosthetic telescope, together with the cornea, acts as a telephoto system to enlarge images 3X or 2.2X, depending on the device model used. The telephoto effect allows images in the central visual field (‘straight ahead vision’) to not be focused directly on the damaged macula, but over other healthy areas of the central and peripheral retina. This generally helps reduce the ‘blind spot’ impairing vision in patients with AMD, hopefully improving their ability to recognize images that were either difficult or impossible to see.

The prosthetic telescope is implanted by an ophthalmic surgeon in an outpatient surgical procedure. The device is implanted in one eye, which provides central vision as described above, while the non-implanted eye provides peripheral vision for mobility and navigation. After the surgical procedure, the patient participates in a structured vision rehabilitation program to maximize their ability to perform daily activities. Situated in the eye, the device allows patients to use natural eye movements to scan the environment and reading materials.

A Phase II/III clinical trial which enrolled over 200 patients is complete.

There are two types of this crappy macular degeneration- a “wet” version, and a “dry” version:

Dry (atrophic) AMD accounts for approximately 90% of all AMD cases. Dry AMD is usually evident as a collection of small, white-yellow fatty deposits called drusen, which accumulate under the macula. This condition results in degeneration of the macula from the aging and thinning of macular tissue. Late stage dry AMD is called geographic atrophy. This condition accounts for many of the new cases of legal blindness due to AMD each year in the US. It is also responsible for a significant portion of permanent vision impairment associated with AMD. There are currently no accepted therapies for dry AMD.

Wet (exudative) AMD is caused by the growth of abnormal blood vessels, or choroidal neovascularization (CNV), under the macula. These abnormal vessels are fragile and leak fluid and blood under the macula, resulting in scarring of the macula. Wet AMD develops in only 10 to 15% percent of individuals with AMD, but usually dramatically affects vision. The end stage of wet AMD is called disciform scar and is often associated with permanent central vision loss. Current and investigational therapies for wet AMD focus on slowing or halting the progression of the disease and include laser photocoagulation, photodynamic therapy (PDT), and investigational anti-angiogenesis drug therapies injected into or in back of the eye. There are currently no accepted therapies for end stage (disciform scar) wet AMD.

Another technological advance in helping people keep their eyesight. I couldn’t imagine this kind of misery, so I hope as many people who need to read this get to read it.

Thanks, VisionCare, for all the info!

British Doctors Tell Age-Related Macular Degernation to Suck It

Have you ever heard of age-related macular degeneration, or AMD?  Do you suffer from AMD?  It is a common form of blindness, and as you get older (hence the age related part), your macula starts to degenerate (hence the degeneration part) and you lose your detail vision.  This sucks, as there hasn’t been much that people can do about it happening until lately.  It’s not a cure per se, but it’s a new technique that doctors are saying might be able to help re-generate part of the macula that needs a bit of wakey-wakey-eggs-and-bakey.

By stimulating a part of the eye called the Bruch’s Membrane, scientists in the UK have been able to slow down degeneration of the macula, and in some cases stop it altogether.  Using a laser to “breathe some life” into the membrane, scientists have been able to wake it up a bit so that it continues to perform its function and not just sit there like a dunce.  The laser treatment takes about ten to fifteen minutes.  Crazy, huh?

Oh yeah – “hey Jim, what is the Bruch’s Membrane, and what does it do?

Bruch’s Membrane is a part of the eye behind the retina, between the retina.  Bruch’s Membrane performs a very, very important function – it removes waste products from the retina and brings in nutrients and oxygen.  You’d think that’s pretty important, huh?  Check out an eye diagram:

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Bruch’s Membrane is part of the Choroid, which lives behind the retina.  When it doesn’t do its job, waste products just build up around the macula and the cells begin to die over time.  The laser treatment targets this membrane to hopefully stimulate it so it starts to perform its waste removal function:

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From the article I read about this procedure in the Daily Mail:

The technique is the brainchild of Professor John Marshall, an ophthalmologist at King’s College London who pioneered laser surgery to correct shortsightedness.

Professor Marshall, who hopes the treatment could be available in a couple of years, said: ‘It is really exciting news. It won’t bring back damaged eyesight but it may prevent AMD.’

The technique rejuvenates the ‘Bruch’s membrane’ – a thin layer that lies behind the retina.

This provides the retina’s light-sensitive cells with nutrients and removes waste created as a by-product of the way retina cells renew themselves.

But the membrane’s cells eventually lose the ability to take waste away, allowing deposits to build up.

It can then become so damaged that the retina’s lightsensitive cells start to die off. In a trial involving more than 100 diabetics, Professor Marshall found that using a laser stimulated the membrane’s tired, ageing cells into action.

After the cells were ‘ energised’ by the laser, they began to clean up the waste again.

Patients also said the treatment led to a ‘ marked improvement’ in their sight.

The non-invasive operation uses a laser modified to give pulses of light that do not damage the eye’s light-sensitive cells or cause any dangerous heating of the target area.

Professor Marshall will now treat up to 200 people with AMD in one eye as part of a second trial. Such patients usually get the disease in the other eye within three years.

He wants to see if the laser prevents the good eye losing its sight. ‘If you can delay the onset by three, four, six, seven or ten years, it’s proof of the principle,’ he said.

Tom Pey, of Guide Dogs for the Blind, which funded the research, said: ‘This is potentially a huge breakthrough for millions. The science behind it is proven.’

The Macular Disease Society said: ‘If this works, then it’s very exciting. However, it will be years before this could be ready for use.’

Let’s hope we read more about this in the very near future!