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The (Bionic) Eyes Have It

August 29, 2002

Heather Heilman
Phone: 865-5714

Gholam Peyman is most well-known as the inventor of the LASIK procedure, but within his field he's famous for a number of innovations. Peyman, a professor of ophthalmology who came to Tulane in 2000 after many years at Louisiana State University and the University of Illinois, developed the first endolaser probes for eye surgery and the operating microscope that represents the current state of the art, among other things.

So when researchers began to work on an artificial retina, they sought Peyman out for his input. Peyman was approached by two groups who are looking for a way to circumvent retinitis pigmentosa, an umbrella term for a number of diseases that affect the photoreceptor cells in the eye. These cells line the rear of the eyeball and convert light into electrical signals through a series of chemical reactions. Researchers are working on ways to mimic this process in patients who can't see or see poorly because of damage to their retinas.

One group, based at Harvard, is working with an implant placed on the surface of the retina. A camera and signal processor mounted on a pair of glasses transmit an image to the chip. Although Peyman thought this was an interesting approach, he ultimately decided to work with Alan and Vincent Chow, co-founders of the Illinois-based Optobionics Corp. who were developing a tiny, light-sensitive silicon chip to be implanted underneath the retina.

"I thought that once you implanted it, it would be stable. It's sandwiched between the retina and the adjacent tissue," Peyman said.

And the device is self-contained and self-controlled, with no battery necessary. They implanted the chip into animals and then a small group of patients. The study has gotten a great deal of attention, with coverage in The New York Times and on "Good Morning America" and "Dateline," even though it's just a preliminary trial to make sure that the implant is safe. Six patients have had the chips for more than two years with no adverse effects.

"We're at the point now that we know it's not harming the patient," Peyman said. But the effectiveness of the chip has yet to be determined. The patients report some im-provement in their vision, but it would be an overstatement to say that the blind can now see. But some of them seem to perceive light or shapes that they couldn't before.

"It's not clear whether the energy generated will be sufficient to restore vision," Peyman said. Larger, controlled trials with placebo chips are needed before the effectiveness of the technique truly can be evaluated. Even so, Peyman said he's impressed with how happy the patients are about even a slight improvement in their vision.

"This is a group of patients that ophthalmologists haven't been able to help," Peyman said. But that is bound to change. Whether the breakthrough comes in the form of a retinal implant or through new gene therapy approaches, he is confident that there will be a way to restore eyesight to people with damaged retinas.

Heather Heilman may be reached at hheilma@tulane.edu.

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