A two-millimeter AI-powered chip developed by Stanford and European researchers helps patients with macular degeneration read again — marking a new era in artificial vision.
Researchers have unveiled the micro-device called PRIMA — a wireless retinal implant so small (just two millimeters) that it’s barely visible to the naked eye. It sits behind the patient’s retina and links to a special pair of glasses.
In trials involving 38 patients, the combination of the implant and the glasses enabled many to read letters, numbers and even words again.
One participant described her pre-implant vision this way: “It was like having two black discs over my eyes.” Afterwards she said: “It’s a new way of seeing through your eyes. It was very exciting when I began to see the letters in a note. It’s not simple, but now I’m learning to read again.”
The results are striking. According to the study, the chip “succeeded in partially restoring vision in more than 80% of patients with age-related macular degeneration (AMD).” AMD is the most common cause of irreversible vision loss in people over 60; in its atrophic (geographic-atrophy) form, it destroys the retina’s photoreceptor cells responsible for central vision, leaving patients with very poor vision.
The PRIMA system pairs:
- A 2-mm photovoltaic microchip implanted behind the retina.
- A pair of augmented-reality glasses equipped with a camera and a small portable computer.
The glasses capture real-world images, process them with an algorithm (via the portable processor), then convert the images into infrared light beams projected onto the implanted chip. The chip turns the infrared light into electrical signals that stimulate the remaining retinal neurons. From there, the visual information travels to the brain via the usual neural pathways—only now assisted and restored.
Because the chip is wireless and powered by the infrared light from the glasses, the system allows patients to zoom up to 12× and enhance contrast. Importantly, the researchers emphasize that it preserves the patient’s natural peripheral vision while adding a prosthetic central vision.
Trial results in brief
- The trial spanned 38 patients from 17 hospitals across five countries.
- Of the 32 who completed one year of follow-up, 27 regained the ability to read; 26 showed “clinically significant improvement” in visual acuity.
- The implant procedure takes less than two hours and the trial reports it is “safe and well tolerated.” Some side-effects (ocular hypertension, small hemorrhages) occurred, but 95% resolved in the first few weeks.
- At present, the PRIMA chip offers black-and-white vision, but the development team is building next-gen versions capable of full grayscale and much higher resolution (chips of up to 10,000 pixels).
Prima could be available in Europe; possibly within the next 1-2 years after CE-mark is granted, depending on regulatory review, manufacturing scale-up and reimbursement arrangements. US: likely a few years later, as US Food & Drug Administration (FDA) approval will require additional data and regulatory process.
For the Latino community and others disproportionately affected by late-stage vision loss, this technology offers a new chance at independence: being able to read again, recognize faces, navigate life. Because the trial includes older adults (average age ~75 years), it speaks directly to the demographic often hardest hit by vision-loss diseases.
