People suffering from one of the leading causes of blindnessthey managed to read again thanks to one tiny wireless chip which is implanted in the back of the eye and to special augmented reality glasses (AR), according to study results published in New England Journal of Medicine.

The clinical trial included 38 European patients, all with an advanced stage of dry macular degeneration known as geographic atrophy.

There is no cure for macular degeneration (AMD), which is caused by inflammation and the accumulation of waste in an area of ​​the retina called the macula. The photoreceptor cells in this area are responsible for sharp, detailed and color vision. When the disease progresses to the stage of geographic atrophy, these cells degenerate and die, resulting in the loss of central vision, that is, the object directly in front may appear blurred or covered by a dark spot.

About 22 million people in the US have AMD, and about 1 million have geographic atrophy, according to the American Macular Degeneration Foundation.

How the PRIMA device works

In the study, participants (average age 79) were fitted with the PRIMA device, a system intended to replicate vision. Patients wear augmented reality glasses with a built-in camera that records their field of vision.

What the camera “sees” is transmitted to the implant inside the eye in the form of infrared light. The chip converts light into electricity, stimulating the remaining healthy cells in the macula in a way that the brain perceives as vision.

An image processor, which the user carries with them, allows the person to enlarge or zoom the image, which is displayed in black and white.

With the help of PRIMA, 80% of the 32 patients who were re-examined one year after the implant showed a clinically significant improvement in vision.

However, there were side effectsmostly related to the surgical procedure: 26 serious adverse events were reported in 19 patients, such as increased pressure in the eye or blood pooling around the retina. Most complications were resolved within two months after implantation.

“It is the first therapeutic approach that has led to an improvement in visual function in this group of patients“said Dr. Frank Holtz, head of the study and chairman of the Department of Ophthalmology at the University Hospital of Bonn.
“Advanced macular degeneration is a devastating disease. Patients can no longer read, drive, watch TV or recognize faces. These results, in my opinion, are revolutionary. It was like I had two black discs in my eyes».

One patient, Sheila Erwin, 70, who received the implant at Moorfields Eye Hospital in London, said that before the operation she felt like she had two black discs in her eyes, with the rest of her field of vision appearing distorted.

Experts are talking about a significant advance

Dr. Sunir Garg, a professor of ophthalmology at Wills Eye Hospital in Philadelphia, who was not involved in the study, called the results a real advance for patients with geographic atrophy.

Until now, doctors could only offer visual aids (such as magnifying glasses) and psychological support.

“Even with new drugs, the best we can do is slow the progression,” said Garg, who works with pharmaceutical companies such as Apellis Pharmaceuticals (maker of the drug pegcetacoplan).
“We cannot stop it, nor restore the lost sight».

Limitations and perspectives

The Greek ophthalmologist, Dr. Dimitrios Vavvas, director of the retina service at Mass Eye and Ear in Boston, said the PRIMA system, while impressive, has limitations.

Implanting the chip requires high surgical skill and involves risks, as the surgeon must lift the retina from its natural position, which can worsen the atrophy.

He noted that the device does not restore normal vision. Patients see in black and white, and need a lot of training to learn to use the new vision. It is not yet clear whether the improvement in visual function translates into a substantial improvement in quality of life.

However, Vavvas was optimistic about the future of the technology: “Think of the device as the first iPhone. The limitations are obvious, but there are specific visual skills that were improved. It is a prototype that shows that the approach has perspective. The next editions will be better.”

New releases and future testing

The PRIMA system was developed by Stanford University Ophthalmology Professor Daniel Palanker and is being developed by Science Corporation, a California-based neurotechnology company.

Palanker said technical improvements are being made to increase the chip’s pixel count from 400 to 10,000. The new chips have already been tested in laboratory animals, and are in production for future human trials. With the help of the camera’s zoom, patients could theoretically reach 20/20 visual acuity.

“We are also working on next-generation software so that patients can perceive not only black and white letters, but also grayscale of natural images such as faces», said Palanker.

He added that the technology could be used in the future for other retinal diseases, such as Stargardt disease, which is similar to AMD but is genetic and occurs in younger people.

The need for more research

Drs Garg and Vavvas stressed the need for larger clinical trials to show whether the device actually improves patients’ daily functioning.

“Is the improvement enough for patients to say “I’ve regained my independence, I can pay my bills, write envelopes, read labels at the supermarket”? This is what I would like to knowGarg said.

Dr. Vavvas added:

“This is a chronic condition, so follow-up beyond a year is needed to see other risks or problems. We want to know if the improvement we see at 12 months remains after two years.”

In conclusion, he said that while the device is not a “miracle cure” for blindness, the study proved that brain-computer interfaces can be an important step in treating severe forms of vision loss.

“As versions of this device improve, it could be a real solution for a group of patients“, he said.