For Bartimaeus, the biblical character who can’t see, it is faith — not physical blindness — that is at the heart of his story. He has no reason to think he will be cured. Still, at the side of the road, he asks Jesus to heal him. As others admonish Bartimaeus for his foolishness, Jesus hears his plea and restores his sight.
Hundreds of years later and long after science replaced faith with cures to common illnesses, blindness remains a mystery. Doubt over the possibility of conquering it has kept a firm grip on eye researchers, if only because the pure act of “seeing” the world before us is so complex — so intricate — that scientists have found it easier to concentrate on simpler problems, such as cataracts. In fact, as little as 20 years ago, any notion that total blindness could be cured was “the laughing stock of ophthalmology,” says Dr. Philip Hessburg, medical director of the Detroit Institute of Ophthalmology at Henry Ford Health System.
“The idea of making blind people see again didn’t have any sway,” Hessburg says. “The problems were so formidable that I think any serious-minded ophthalmologist wanted to concentrate on problems that seemed solvable. Why spin your wheels on something that doesn’t look like it’s ever going to work?”
Hessburg often uses the story of Bartimaeus to illustrate why belief is just as important as science in conquering what might be the last frontier of his profession. Without it, the problem of blindness can seem overwhelming and easy to dismiss, Hessburg says.
Even so, from his practice in Grosse Pointe, where he’s dedicated his entire career to helping blind people adapt to life, Hessburg knew there were researchers around the world some 20 years ago who were at least beginning to come close on giving blind people some form of “visual panorama” through the development of neuro-prosthetic devices for the eye.
And yet they were disjointed — none of them knew what their colleagues were doing, or if their research might complement someone else’s. So Hessburg created an international congress of researchers who now converge every two years in Detroit. It is the only comprehensive collaboration in the world working on a neuro-prosthetic device.
These collaborations — the eighth one over the past 16 years took place last fall — are proving extremely valuable in the race to develop better neuro-prosthetic devices, which are implanted in a blind person’s eyes and can, in essence, create an electronic interface with the brain in order to restore visual connections.
This gathering of the world’s top researchers in artificial vision has made Detroit an unlikely hot spot for attacking blindness head-on in a town better known for its automotive industry.
But no devices are being developed here at the moment — nor in most other places, for that matter. Only one neuro-prosthetic device designed to create artificial vision is on the world market today. It’s called the Argus II Retinal Prosthesis System, or the “bionic eye,” and it was invented by Second Sight Medical Products Inc. in California.
The Argus II is a retinal implant designed to stimulate the retina and provide visual perception for people suffering from retinitis pigmentosa, a degenerative form of blindness. It was approved on a “humanitarian” basis in 2013 by the U.S. Food and Drug Administration — that is, the FDA is allowing its use on the market because of its potential to help some blind people, though its effectiveness is still unproven. It costs about $100,000, contains about 60 micro-electrodes, and has the potential for producing simple black-and-white perception so blind people can at least distinguish light from dark, or the difference between a wall and a door.
For blind people who live in a world of darkness, any upgrade to some form of visual perception is a huge improvement.
“Of course, for anyone who can see, these results would be horrible,” Hessburg says. “But if this morning you awakened totally blind, the ability to recover light perception so you knew it was daybreak, the ability to see a dark hamburger against a white plate, or the ability to walk in the street and know the different between the grass and the sidewalk — that would be huge.”
The Argus II unfortunately still can’t provide a high-quality form of sight, the type of vision most of us have, where colors and objects are sharply defined and in focus. In short, in the past 20 years or so that the Detroit Institute of Ophthalmology has pushed for collaboration to create artificial vision, progress is slow — but promising.
Hessburg compares this time in ophthalmology with the initial discovery of antibiotics that eventually led to the eradication of so much disease. “We are right at the stage where Alexander Fleming was in 1928 when he discovered mold in a petri dish that led to the discovery of penicillin,” Hessburg says. “We are at the dawning of a new age in artificial vision, which is going to be as important as antibiotics or more so for people who have lost their sight and hope to see again.”
Brendan Patrick, an artist in Ferndale, has waited for this moment for seven years. When he was 26, he had to spend months in the hospital after a lifelong battle with cystic fibrosis caught up to him. He needed a lung transplant, had to be hooked up to a ventilator while he waited, and had to be on various antibiotics and other medications along the way.
“There was just so much trauma going on in my body,” Patrick says. Then, after the surgery, Patrick woke up to complete blindness, a complication of the many things that were physically wrong with him at the time.
“Now all I see is 100 percent pitch black,” Patrick says. “For the first two days, all I did was cry. I mean, I couldn’t begin to wrap my head around what was going on. I’m an artist. Where was I going to go from here?”
For adults like Patrick who go blind after living a life with vision, the change can be particularly disturbing and totally devastating, Hessburg says. And yet Patrick adapted. He went to “blind boot camp” where he learned techniques to navigate unfamiliar surroundings and “cross the street without getting hit by a car.” He has adapted his artistic style — he uses a puffy paint to make outlines of what he wants to draw and then feels the outlines with his hands to fill in with color. “It’s like paint by numbers,” Patrick says.
Patrick has learned how to read Braille, and he uses the language to label his music CDs and his paints. But he says he’s been impressed with the modern technology all around him that is useful for blind people. “My computer and my iPhone talk to me,” Patrick says. “It almost makes Braille obsolete for me, the technology is that advanced.”
What Patrick doesn’t have is a firm answer on whether that technology that makes all of our lives easier will one day truly help him to see again. “The doctors tell me now just to keep my fingers crossed — that it will happen in 10 years.”
Dr. Joseph F. Rizzo, a professor of neuro-ophthalmology at Harvard Medical School and a member of the research congress that meets in Detroit, agrees that the technology still has a long way to go.
“The devices we’ve created so far haven’t created the types of benefits we really want,” Rizzo says.
Part of the reason for this is indeed the complexity of the sense of sight. Photoreceptors basically receive incoming light and turn it into a nerve signal that travels to the brain. The problem is that there are so many nerve cells — 150 million — in the retina of the eye alone, not to mention the hundreds of millions of nerve cells within the brain doing their part as well to receive the nerve signals. It’s an utter web of activity and chaos that somehow produces all the beautiful pictures we call “sight” — and it is something taken for granted by most of us who can see.
Researchers must figure out how to stimulate as many nerve cells as possible to create the best chance for vision in people who have lost their sight due to disease or other trauma. The ear, by contrast, is much less complex, a reason why neuro-prostheses implanted into people who have lost their hearing have been much more successful. Cochlear implants have about 16 micro-electrodes that stimulate nerves within the ear, and this can produce optimal hearing levels in many patients. With more than three times as many electrodes, the Argus II produces relatively poor sight.
Much of the work being done now is on how to increase the number of small pockets of cells that a neuro-prosthetic device could stimulate, thereby helping to make a picture more “clear,” much like how a higher amount of pixels can make a computer screen seem more clear and easy to see. The Boston retinal prosthesis that Rizzo is developing at Harvard aims to do just that and is in the testing phase.
Another promising device in the testing phase in Germany is the 1,500-pixel sub-retinal implant, which also has the ability to stimulate many more nerve cells than the device currently on the market.
As the research goes on, perhaps in 10 years there really will be a device capable of giving back someone like Patrick his sight — and more so than just visual impressions that help him to see where the sidewalk begins and ends. Will color play a part? Will a blind artist like Patrick actually be able to see what his paintings look like in the future?
Hessburg believes the researchers can get close — yet another reason he plans to continue bringing the best artificial vision researchers to Detroit on a regular basis.
“Collegiality facilitates collaboration, and collaboration accelerates progress.”
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