Bionic Retinas Give Patients Sight

The Noof writes " Yahoo News is running a story about patients who have been given partial sight thanks to implants of silicon-based bionic retinas. " The article notes that the implant is having a "rescue effect" on the other components of the retina, restoring cells around the implant and making them useful again." Amazing stuff.

Comments

question

[CmdrSanity]

So I guess the most obvious question is: how long before the bionic retina is better than the real thing and would you get one?

Neat stuff.

Re:question

[istartedi]

Let's build on that. How dense could the sensors get before the optical limits of the eye would become the bottleneck?

Also, since these things are using the photo-voltaic effect to generate the electrical impulse, isn't there a limit to how well they would work in low light? Can that limit be overcome? Could they build units that grabbed inductive power from a transmitter in your glasses to overcome that problem, or maybe even allow super night vision? Will future soldiers be encouraged to get such implants? On the opposite side of that equation, would they allow you to look at the sun without being damaged?

Re:question

[Aix]

I think you underestimate just how good human biological vision really is. It is easy to think at first that rods and cones are just like CCDs or pixels or whatever. It is far more complicated than that. In fact, there is extensive research that demonstrates that you can see in higher resolution than should be optically possible. The reason this works is complicated, but basically comes down to the fact that there is an immense amount of inter-cellular interpolation going on. It can be modeled simplistically as an array of voltage sources.

A good starter paper might be the classic "What the Frog's Eye Tells The Frog's Brain" by McCullough, Pitts and Lettvin. (From MIT's RLE Lab in the 50's) More recently, Marr's stuff is supposed to be very good.

Improvements

[chill]

How long until they offer an "improved" version, that has an overlaid clock/calendar, or just a HUD connected to the implanted, bone-conductive phone?

How about that "cybog" professor and all the hassles he had getting past airport security. While these things are tiny, I can easily forsee a future whene implants are regulated country-by-country.

"Sorry sir. Memory-storage implants are not legal in Canada. You must reboard the airplane."

Johnny Mnemonic, here we come.

Can it be DoS'd?

[Jon Howard]

What kind of interference will upset the function of this device which wouldn't affect a normal eye? Can it be remotely manipulated in such a way as to malfunction or function in a way that a remote attacker may desire it to function?

The fact that I have to ask these questions makes me hesitant to put electronics in my head, but I can imagine that the concern would be less for someone who couldn't see without them.

That's just great. Really.

[dlek]

It's nice to see technology that really improves people's lives, instead of possibly giving slight and ambiguous gains to their productivity or make it that much easier to send 10-word messages to other people within urban areas. I like advancements in 3d vid cards and such as much as the next guy, but this is what technology's really all about. Helping the blind see again? Excellent. I'd give back the Internet if it would find us a cure for cancer.

Re:Full Article Text

[0x0d0a]

Yes, it would be awful if Yahoo got slashdotted, wouldn't it? Better post the article, just to make sure.

Limited Potential

[Jon_Katz (Paranoid F]

While this indeed is a great innovation, we must remember that this has only been tested by people affected by retinitis pigmentosa. Whether the optical implants can be used to restore sight for people from eye injuries or other diseases remains to be seen.

A lowdown on retinitis pigmentosa can be found here.

Re:Limited Potential

[mr_exit]

WOW this is the greatest news I have heard all year.... it has totally made my day.

Ok calm down... explanation time..

I have had retina reatachment surgery 3 times in two years. this is where they take your eyes out, cut open the 6 rows of stiches in each eye and stick the retina back on. They dont know what is causing it (not bungee jumping or a car accident) and everytime it happens my retina gets a little more cut up and i have all sorts of weird stripes through my vision.

Now you my say.. "tough luck, you have bad eyes, live with it" but you see my whole life is based arround my eyes. I am a visual effects artist for the movies (lately 3d modeling on a movie about a ring) my eyes are my livilyhood.

And so the chance that they are one step closer to being able to replace them matters more to me then anything i have heard all year.

So if this is the "limited potential" you are talking about mr katz then i'm not really sorry for getting excited for nothing

Only for those who lost their sight

[Hitokage_Nishino]

There is an extremely interesting article in a recent Discover magazine about a man who was blind from the age of 2-3 recieving sight back in one eye thanks to stem cell implants.

While after the operation he physically had 20/20 vision, he actually saw more along the lines of 20/500. The problem wasn't his eye, but his brain. He just hadn't learned how to fully percieve eyesight. One interesting note is that he does not perceive optical illusions. Since he's well past that critical stage of mental development when one is supposed to get it hardwired, he'll have a rough time getting his eyesight anywhere near normal. In fact, several other people who were blind as small children and had similar operations say they would rather be blind now.

At any rate, while this will certainly be a great help to those who lost their sight as adults... it may not be of too much help to those born blind.

More technical details

[martyb]

There's much more detail on the history, design, and development of the device in this EE times article. I was especially struck by how they persevered. They started on this in 1990 and things did not go entirely smoothly:

"There were 50 to 75 major hurdles from the time we started," Vincent Chow said. "The biocompatibility side represented probably 40 percent of the issues. The other 60 percent were really in the electrical performance of our structures. That's because the final stimulation is an ionic stimulation. We're basically trying to interface a solar structure so that the microcurrents produced by the solar cell have a very high efficiency or functionality factor to stimulate the cells that are touching these particular areas."

This version of the device contains about 3500 light detecting cells. If this version works out okay, they are planning to develop a much larger version of the chip.

If the ASR chip is successful in restoring some degree of vision, Optobionics will make modifications to a final and significantly larger chip design. Some possible ideas, said Alan Chow, include placing openings in the chip to allow nourishment to flow between the outer and inner retina; and changing the direction of the electrical stimulation on an ongoing basis, a technique referred to as biphasic stimulation.

Reporting from ARVO

[BWJones]

OK, I am one of the scientists here at ARVO (Association for Research and Vision in Ophthalmology), and was present at the presentation of Dr. Chow.

I for one would love to believe in the results, but I have not seen any real scientific proof that these things work as advertised. While the video of patients was impressive and touching, there is very little hard science behind the development of the bionic retina and how it is integrating into the retinal environment. The only thing that everyone appears to be reporting on is that the chip is not rejected. And there are other more fundamental issues at work. For one, the silicon retinas require the equivalent of 3X's the brightness of the sun to activate the device and for realistic performace, they would require an external power source. The other issue is that the retinal circuitry that they are placing this bionic implant onto is severely degenerated and remodeled in these patients and may continue to degenerate further, thus complicating matters. That said, there is some indication that the surgery itself may cause some retinal rescue, not the implant. This is something they have not done control experiments on. Furthermore, the generation of low voltage current from the implant in the retina may be promoting retinal recovery of sorts while the silicon retina may not be doing anything for vision itself.

We are still a looooong ways away from the idea of a bionic retina and I think that retinal implants will actually be the least effective method in the long run. Gene therapy, viral infective methods, stem cells, and post retinal bionics will probably work optimally sooner.