Here’s Looking at You:
Study evaluates vision loss treatment
Imagine a tiny silicone implant — just two millimeters in diameter, less than the thickness of a human hair — that could restore vision in people with retinal diseases such as macular degeneration and retinitis pigmentosa.
Ophthalmologists at Rush University Medical Center in Chicago have more than just imagined it. One doctor on faculty at Rush, Alan Chow, MD, helped develop such a chip, called the artificial silicon retina (ASR). And a group of ophthalmologists at Rush, including principal investigator John Pollack, MD, as well as Kirk Packo, MD, Pauline Merrill, MD, Mathew MacCumber, MD, and Jack Cohen, MD, are evaluating whether this chip can help patients with retinitis pigmentosa — patients who are considered legally blind.
The chip, which is surgically implanted using tiny holes no larger than a pin, works by replacing damaged light-sensing cells in the eye. Using thousands of microscopic cells, it converts light into electrical impulses to stimulate the retina.
This study is an expansion of a trial performed in 2002. In that study, all patients reported some degree of improvement in visual function. “Improvement in visual function was variable and included the ability to read letters, improvement in color vision and expansion of their visual field,” says Pollack. “Some patients have experienced improvement in activities of daily living such as improved ambulation — not bumping into objects around the house — and reading the time on a clock.”
One of these patients, Maria Zaccaro, shared her story with WGN News in February. Zaccaro was just 25-years-old when she noticed her vision deteriorating. Eventually, she found herself unable to see the people and things she enjoyed most because of retinal pigmentosa. Simply reading or watching her son play basketball became problematic.
But life changed after the implant.
“Looking at the scenery, everything looked white before,” Zaccaro says. “Now, if there are mountains, you can see them because of the contrast ... the trees, the water, the cars going by.”
Although it’s too soon to predict the findings of the current study, ongoing research at Rush and around the country offers hope to the millions facing retinal diseases.