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Patients get Solar Implants in Eyes
Ben Sullivan writes "As reported at Science Blog, ophthalmologists have implanted Artificial Silicon Retina microchips in the eyes of five patients to treat vision loss caused by retinitis pigmentosa. The implant is a 2mm chip that contains about 5,000 microscopic solar cells that convert light into electrical impulses. Already some patients have experienced improvements such as not bumping into objects around the house, and being able to read the time on a clock."
I guess it sounds more exciting to call them "solar cells," but obviously they're light sensors. If they were originally developed for use in solar electricity production, that should be in article, not the headline. "Matters for Nerds. Stuff that News!"
The article really doesn't explain why the chips are reffered to as "solar" cell implants. Are these people only going to be able to see light from the sun (I doubt it). I guess they just lacked a better word for the cells, any other suggestions as to why this is?
The ASR chip contains approximately 5,000 microscopic solar cells that convert light into electrical impulses.
5000 cells, that's an area of 70x70 cells. Is that enough to see with or am I missing something?
-- Cheers!
This is great news. I've been following these procedures for quite some time. Retinitis Pigmentosa runs in our family.
One thing to point out is that this disease is a degeneration of the retina. It's called pigmentosa due to the fact that as the retinal cells die, small spots appear on the retina. The degenerations starts on the outside, and moves inward, creating a tunnel-like feeling for the patient.
My uncle had surgery in Cuba (We live in Guatemala, so let's just skip the whole Cuba-American posts) where they operated his retina, and treated it with oxygen and Ozone therapies. This type of operation is not intended to cure it, but to stop it. This was about 5 years ago, and his retinitis pigmentosa has not spread, but it's still a bit early to know for sure.
If you have more questions there is tons of information on the web
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Arturo Mijangos
Well considering that the website refers to an article in Russia's Pravda, which has stories called "Boriska-boy from Mars" , "Humans Learn to Fly" , "Soviet Army Fought UFOs" etc. I wouldn't lend too much credence to this.
Or who knows maybe years of exposure to radiation from atomic bomb testing has given Russians superpowers.
Pshaw. Five seconds of thought about the problem provides you with a proper 21st century definition of a soul.
If your brain is hardware, your soul is the software.
Next question.
Hell is being intelligent in a world full of idiots.
I think to produce color, there will be a need to setup color filters (just like color pixels you have on your computer monitor,) and do something with outputs from different color filters, maybe use different electrical frequencies for different colors or apply different voltages to cells that are very close to simulate color additions. The filters will only let specific light frequencies through, and will produce different voltage depending on the intensity of its own wavelength, so maybe multiples of the wavelengths can be used as electrical frequencies to represent specific colors?
You can't handle the truth.
IAAVN (I Am A Visual Neuroscientist) working on artificial vision. I have seen presentations on this approach, and unlike many of the other efforts in this field, Dr. Chow's claims appear astonishingly good.
The basic idea is beautiful and elegant: you put an array of tiny photodiodes behind the retina, exactly where the photoreceptor cells (rods and cones) are. Shining light on each of these nearly-cell-sized photodiodes creates a localized voltage which should stimulate a small handful of cells, generating a signal that will mimic the original biologically transduced input to the retina. The photodiodes nicely supplant the dying photosensitive cells. It sounds perfect.
I was very impressed with their presentation at a one-day symposium on artificial vision I attended at USC a few years ago, until one of the audience members pointed out that they had done some calculations, and it seemed that one would need incredibly high light levels to generate enough current to stimulate the local cells. Dr. Chow admitted that, even being optimistic about the conversion efficiency of photodiodes (which here need to be optimized for biocompatibility more than efficiency), the physics involved dictates that you would need light bright enough to cause damage to even the non-photosensitive tissue to get the device to work. Dr. Chow then backpedaled to say that even if the device cannot restore lost vision, it can perhaps supplant any remaining healty cells to improve vision in low-sighted patients. That question-anwer cycle was the first point in his presentation where he backed off from the claim of restoring full vision to blind patients.
Dr. Chow's results were done in a private laboratory, part of a company set up to profit from his advances. He must answer to his shareholders, and his results are not open to the level of scruitiny that standard scientific claims are. He was reluctant to answer questions at this session. Therefore, as a scientist I am bound by the lack of openness to view his claims with a grain of salt.
Other efforts to create artificial vision are still having trouble with just a handful of points of light. While I believe that the subretinal approach has a good chance of eventually proving fruitful, using a silicon-based device that lacks an external power source just cannot produce normal vision. This is why the article concentrates on the improvements in existing low vision, rather than discussing restoration of lost vision.
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.