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Journey Toward Sight Artificial Retina Brings Light to the Blind May 8, 2002 — Debbie Bennett's retinas stopped working 23 years ago, and suddenly, her sight abandoned her.

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"I was reading a book. And all of a sudden, my vision just went," Bennett told ABCNEWS' Science Editor Michael Guillen. "It was devastating."

Her mom, brother and two cousins also went blind, because each carried the same genetic defect, called retinitis pigmentosa. Even Bennett's 6-year-old niece has the defect, although its impact hasn't kicked in yet.

"I tell her that my eyes are broken," Bennett said. "And she understands that. Then she'll say, 'Will my eyes be broken?' And then I just break out crying, and I say … 'hopefully not.'"

But Bennett has found hope in the pioneering work of Dr. Alan Chow, a Chicago eye doctor who has developed an artificial retina to help people whose own retinas are defective.

So far, the "bionic retina" has allowed Bennett, and others who were blind, to improve their abilities to see, such as the ability to distinguish light from shadow, according to Chow, who today announced the results of his two-year Food and Drug Administration trial on humans. Chow said one patient, who has had the implant for nine months, saw his wife's face for the first time in years. The man, who previously could only see hand motions from four to five feet away, can now see cars from half a block away.

Another patient, who could not detect light even if a bright light was pointed at his eye, now knows when he needs to turn off his porch light. The hope is that it will eventually be able to restore sight for those who are blind due to defective retinas.

The trial includes three patients implanted with the chips for nine months and three implanted for 21 months. Patients range in age from 45 to 76. All had lost their vision to retinitis pigmentosa, a hereditary condition in which the retina gradually degenerates.


The Fragile Miracle of Sight
The human eye is a very fragile miracle. If you damage the tissue-paper thin layer of cells that make up the retina, everything goes dark. Defective retinas are the world's leading cause of blindness.

Chow left a lucrative ophthalmology practice and teamed up with his brother Vince to search for the holy grail of vision research: a bionic retina.

"I'm quite lucky to be able to be involved in an area that, if we're successful, we would really make a difference," Chow said.

The brothers invented a wafer-thin array of photocells that are surgically placed beneath the patient's defective retina. Only six patients have braved the historic surgery — and so far the results have been promising. Chow said the study was conducted to determine whether the device is safe.

"At this time, there doesn't seem to be any signs of rejection, inflammation, infection," Chow said. "And the patients are in no discomfort."


Vision of a Christmas Tree
Two years ago, Chow put an artificial retina into Bennett's right eye. Before surgery she couldn't see a thing, but when the bandages came off, she was shocked.

She can now see light and shadow, which means she can slowly find her way around. Bennett still cannot see shapes. But is it better than what she had before?

"Oh Lord, yes, yes," Bennett said.

John Crocker, another of Chow's patients, was blind for more than 50 years. But right after his operation, he got a huge surprise.

"I was walking through the house," Crocker said. "And I stopped and I looked and I could see the lights on our Christmas tree, which is the first time that's ever happened for a long time."

The artificial retina is years away from being perfected, and in the meantime, Chow is not making any false promises. He is not sure if he can get patients to the point where they can read a newspaper, for example.

"We don't know," Chow said. "I wish I could tell you at this point."

Staring the Future in the Face?
But seeing is believing. And now that these patients have gotten a glimpse of the future, they can't wait to stare it in the face. Bennett said she would like to at least be able to see those around her.

"Just to be able to see a little bit, like faces, distinguish people," she said.

And what if someday she could see faces?

"Oh my gosh! I'll have a big party," Bennett said.

Crocker has one wish before he dies. "To see a face, my wife," he said, his eyes tearing up.


ABCNEWS' Melissa Dunst produced this story for Good Morning America.