“A new era”. Experts hail 'remarkable' success of subretinal chip implant that can restore lost sight

An electronic eye implant half the thickness of a hair has helped people with sight loss see again, ushering in a potential “new era” in the fight against blindness, The Guardian wrote on Monday.

Doctors who implanted the SIM card-shaped prosthetic devices say they helped many of the 38 elderly patients in the study regain the ability to read letters, numbers and words.

“In the history of artificial vision, this represents a new era,” said Mahi Muqit, senior consultant at Moorfields Eye Hospital in London, one of 17 centers involved in the study.

“Blind patients can benefit from a significant restoration of their central vision, which has never happened before. Regaining the ability to read is a major improvement in their quality of life, boosts their optimism and helps them regain their confidence and independence,” he added.

The study found that 84 percent of participants were able to read letters, numbers and words again after being implanted with the device, called Prima.

Ophthalmologists hailed the results as “remarkable” and said the device could help people with the “dry” form of age-related macular degeneration (AMD). AMD is a progressive eye disease that affects central vision and is the leading cause of vision loss in people over 50. There are two main types of this condition: the atrophic variant, which is more common and progresses slowly, and the exudative variant, which can progress rapidly.

Moorfields Hospital said: “The revolutionary new implant is the first device to enable people to read letters, numbers and words with one eye that has lost sight.”

All 38 patients in the study had the dry form of DMLV, which over time leads to progressive vision loss and for which there is no treatment.

Most people with this condition lose some of their central vision, and in some cases it progresses to complete vision loss as the cells in the macula die and the central macula melts. The macula is a small area in the center of the retina responsible for detailed central vision, such as reading and recognizing faces.

All of the participants had lost their central vision and only had limited peripheral vision before having the device implanted in an operation that took less than two hours. Five of them were treated at Moorfields and the others at hospitals in Germany, France, Italy and the Netherlands.

Sheila Irvine from Wiltshire, one of the people who had the chip implanted at Moorfields, said: “Before I got the implant it was like I had two black discs in my eye with the outside distorted. I was a bad reader and I wanted to get that ability back. I didn't feel any pain during the operation but you are aware of what is happening. It is a big difference. It is a new way of seeing through the eyes and it was extremely exciting when I began to see a letter. It's not easy to learn to read again, but the more hours I put in, the better I get at it.”

The Prima device, a super-thin microchip measuring just 2mm by 2mm, is inserted under the center of the eye's retina in a procedure known as vitrectomy, an eye surgery that involves removing part or all of the vitreous.

To help them see and write, patients were given augmented reality glasses containing a video camera connected to a small computer, which they attached to their belt. The glasses include a zoom feature to enlarge text and make it easier to read.

Patients can use the glasses to focus and scan the object in the projected image they want to read. The glasses project the scenes as an infrared beam over the chip, which activates the device. Artificial intelligence (AI) in the computer on the belt processes the information and converts it into an electrical signal, which passes through cells in the retina and the optic nerve in the brain.

Muqit stressed that patients must undergo an intensive eye training and rehabilitation program to benefit from the benefits of this technology.

“It's not like you put a chip in your eye and then you can see again. You have to learn to use that kind of vision,” he said.

Close-up of a girl's eye, in which a chip is implanted. Illustrative photo. SOURCE: © Alona Siniehina | Dreamstime.com