Bionic eye implants let Canadian patients perceive light
Published Tuesday, October 14, 2014 12:13PM EDT
Last Updated Tuesday, October 14, 2014 6:03PM EDT
For the first time ever in Canada, two patients with severely impaired vision have received “bionic eyes” that will not restore their sight, but will allow them to once again perceive light.
Doctors at Toronto Western Hospital say the two patients have retinitis pigmentosa, a degenerative disease in which the retina progressively becomes so damaged that most, if not all, vision is lost.
The bionic eye is known officially as the Argus II Retinal Prosthesis Device, and has two parts: The patient is outfitted with a pair of glasses with a built-in video camera, while a prosthesis the size of a pencil eraser is surgically implanted onto the retina.
Information from the camera is wirelessly transmitted to electrodes in the implant and converted to electrical pulses. These electrical pulses are turned into images, which are transmitted to the brain, Toronto Western’s Dr. Robert Devenyi explained to CTV News.
The patient must undergo intensive rehabilitation to learn how to process these images, he said.
The device stimulates the retina the same way that light normally does, just electronically, Devenyi said.
“It really allows us to give vision to people who have no vision, and have no options for any type of rehabilitation,” Devenyi told CTV.
One of the Canadian patients is Orly Shamir, who had some residual vision as a child, but for the past dozen or so years could not see anything.
“After surgery and recovery, it’s like going back to childhood,” Shamir told CTV News Channel Tuesday afternoon.
Doctors tested Shamir’s vision before her surgery, and she was unable to detect a moving square on a computer screen. She was re-tested two weeks ago, and was able to detect the square, as well as the movement of a line across the screen.
“For me, it was very emotional because before I could not see any of it and now I can,” she said.
She was also able to see black and white stripes on a square board.
Shamir’s rehabilitation is ongoing. “I’m really excited about what’s to come,” she said.
Just last week, a patient who lost his vision to retinitis pigmentosa three decades ago had his bionic eye activated at Duke University Eye Center. Larry Hester was only the seventh patient in the U.S. to receive the bionic eye. When doctors activated the device, he exclaimed “Yes!”
Each implant costs US$144,000, Devenyi said, and the device is currently only approved by Health Canada for use in his study.
However, he anticipates that the federal agency will approve the device for wider use “very shortly,” and hope that it will be publicly funded.
Devenyi noted that not all patients with retinal degeneration will qualify for the bionic eye. Between 1,000 and 1,500 patients may be eligible, he said.