When someone develops age-related macular degeneration (AMD), reading a message, recognising a face, or seeing the centre of a page can become extremely hard. A new approach uses a tiny, solar-powered chip placed under the retina plus special glasses to bring back some central vision. Here’s how this science-meets-medicine idea works—and why it matters.
What’s going on in AMD—and what is “geographic atrophy”?
In AMD, the macula (the sharp-vision part of the retina) wears out over time. In the dry form, a late stage called geographic atrophy (GA) develops—patches of cells die, leaving a central blind spot. Current medicines can slow GA a little, but they don’t restore lost sight. That’s the gap this new implant tries to fill.
Key terms (quick definitions):
- Retina: Light-sensing layer at the back of your eye.
- Macula: Small central area for detailed vision (reading, faces).
- Geographic atrophy (GA): Patches of cell loss in dry AMD causing central blind spots.
- Subretinal: Under the retina.
- Photovoltaic: Turns light into electricity (like a solar panel).
Meet PRIMA: a subretinal “solar” micro-chip
The PRIMA system is a 2 mm × 2 mm ultra-thin silicon chip that sits under the damaged macula. It has hundreds of tiny pixels that convert near-infrared light into gentle electrical pulses that stimulate the inner retinal cells still alive. Those cells then pass the signal to the brain—creating a new form of central vision. The lenses are clear, so users keep their natural peripheral vision while the chip provides prosthetic central vision.
How the setup works (simple steps):
- A camera on the glasses captures the scene.
- A pocket processor boosts contrast and can zoom.
- The glasses project a safe near-infrared image onto the chip.
- The chip converts light to electricity and stimulates the retina.
- Signals travel through the optic nerve to the brain—producing sight.
What did the study show?
In a multicentre clinical study of 38 people with GA due to AMD, 81% of those assessed at 12 months saw a clinically meaningful improvement in central visual acuity when using the PRIMA system (that’s at least 10 letters better on a standard eye chart). Using a method to account for missing data, the overall estimate was ~80% improving at 12 months. Many participants used the device at home; 84% reported reading letters, numbers, or words with it.
A few more helpful details:
- Average improvement at 12 months was about 25 letters (roughly 0.5 logMAR).
- The maximum improvement seen with the glasses was 59 letters.
- Natural peripheral vision stayed about the same as before surgery.
Safety: what risks were seen?
Like any eye surgery, implantation isn’t risk-free. In the first year, there were 26 serious adverse events in 19 participants, mostly within two months of surgery and mostly resolved. Reported issues included raised eye pressure, small retinal breaks, small bleeds under the retina, and rare events like retinal detachment. Importantly, the study’s monitoring board decided the benefits outweighed the risks for this group, but longer follow-up is still needed.
What can this actually help people do?
Because the system can zoom and boost contrast, it can make small print and high-contrast shapes easier to see in the centre of vision. People still use their own peripheral vision for navigating, while the chip helps with detail tasks like reading larger fonts, spotting letters, and writing in the central field. It’s not the same as a healthy retina, but it’s a meaningful gain for many.
Reflection: If someone in your family had a central blind spot from AMD, which everyday task—reading a birthday card, recognising a face, or writing a note—would mean the most to get back?
