Mina Chung, M.D.

Eye doctor part of a team of physicians at UR Medicine that restored some vision to a blind woman using a new ‘bionic eye’

ChungQ: You’ve recently used a new device to restore sight to a patient. What’s the device and how does it work?

A: This new implant, which they call a retinal prosthesis, was recently approved by the FDA for use. So we went through the process to obtain it for the University of Rochester, and we’re the first in New York to put one in. Basically it works for a type of retinal degeneration which previously had no treatment and, in the most severe cases, could leave people completely blind. The implant consists of an electrode array that gets surgically implanted on top of the retina. In this condition, the rods and cones are deteriorated, but the nerves of the inner retina are still intact. So the electrode array is connected to a camera, which the person can wear on a pair of glasses and that transmits a wireless signal to a transponder that’s on the eye.

Q: Does this need an external power source? How long does it last?

A: It lasts permanently. The part that’s inside the eye does not need a power source but the camera has a power source that has a battery pack they can wear on their waist.

Q: And that’s physically connected?

A: Yeah. So the camera is connected to the power source by a wire, but the part inside the eye is totally wireless.

Q: What percentage of blindness cases can this technology help?

A: This is a fairly rare case of blindness. It works in cases where the eye, the nerve and the inner layers of the retina are still intact. So it’s a fairly rare condition where only the rods and cones are deteriorated. It’s called retinitis pigmentosa. It affects about one in 50,000 people.

Q: Do you see potential for broader applications?

A: This is just a very first case, and it purposefully selected for people who are completely blind. It does seem to work well to help those people identify targets and navigate. They might be extending it to people who aren’t as blind. It may also work for people with other kinds of retinal degeneration.

Q: How long is the procedure?

A: It took about four hours for us to put it in. It’s a regular surgery. The way it works is we put the transponder on the outside of the eye. The really critical part is the electrode array that needs to lay right on top of the retina. There’s a surgery I routinely do for retinal detachments called a retinal vitrectomy. So we do that and implant it inside the eye. It takes a little bit of doing. The team from the company that makes the device was there to make sure all the parts were working, so there are a few checkpoints along the way to make sure all the electrodes are working correctly and everything was in the right place. The process builds on techniques that are standard for retinal surgeries.

Q: How much does the device cost. Is it covered by insurance?

A: Luckily the device was approved by Medicare. Most of the insurance companies follow the Medicare guidance. It is quite costly. The implant costs $120,000 and the procedure and training period to interpret the images brings it to about $150,000.

Q: What does sight look like for a person who receives this implant? What kinds of images are they receiving?

A: The retina is a nerve that is responsible for vision. Things that stimulate the retina cause a person to see a spark or a flash. So these electrodes now stimulate the retina to create a flash image on each place in the grid array. Those electrodes are stimulated based on contrasts of images that they camera sees. So you can imagine a pixel array of dots. That’s what they see. They need to move the camera across borders, so if they look at a sidewalk, they’ll see signals about where the borders are.

Q: How hard is it to get the hang of?

A: After the implantation the eye needs time to heal, so we actually don’t turn it on for about a month. At the one month visit we turned it on, and there was a two-hour training session with the company. On that first day our patient was able to see motions and identify a sign that was on the wall by its border. So she was able to see some signals right away, but she had to practice with it when she got home. It’s been a few weeks since she turned it on. She told us she’s able to walk down the hallway of her house and see out the window. She can see the railing of her deck and items in her hallway that she used to trip over. It’s helps with independence and navigation. We anticipate people will learn how to use it better over time.

Q: To geek out for a moment, this sounds a lot like cybernetics?

A: Yeah, they’re calling it the bionic eye. It is kind of science fiction sounding, and it’s amazing that technology has gotten to this point. It’s really something that we had no treatment for.

Q: Are you going to be training other surgeons in how to do this?

A: Our group, Dr. Ajay Kuriyan and myself, did the training program at another site and then had a proctor come and proctor us the first time. The company has a network of people who have completed the training, so now we can help others and act as proctors for them.

In the News

A 71-year-old woman blinded by an inherited disease recently thrilled University of Rochester doctors by reaching out and grabbing her ophthalmologist’s hand after receiving a “bionic eye.” The device allows her to distinguish light and motion, which she hasn’t been able to do in decades. She is the first person in New York to receive the FDA-approved Argus II Retinal Prosthesis System. Physician Mina Chung of the Flaum Eye Institute worked with retina specialist Ajay Kuriyan, and anesthesiologist Anil Pisharoty to implant the device Aug. 29 activate it Sept. 24.


Name: Mina Chung, M.D.
Position: Associate professor of ophthalmology at the University of Rochester
Hometown: Bronx, NY
Education: Yale University, bachelor and medical degrees; post-doctoral training and residency: USC University Hospital; internship in ophthalmology at Greenwich Hospital
Affiliations: University of Rochester Medical system
Organizations: American Academy of Ophthalmology; American Society of Retina Specialists, Macula Society
Family: Married
Hobbies: Running