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A groundbreaking clinical trial has shown that the AI-enabled retinal implant known as PRIMA has enabled reading ability in patients who had previously lost central vision due to geographic atrophy, a form of dry Age-Related Macular Degeneration (AMD). Of the 38 participants across five countries, 84 percent regained the ability to identify letters, numbers, and words using the system.
How the Technology Works
The PRIMA system consists of three primary components: a 2 mm × 2 mm photovoltaic chip implanted beneath the retina, augmented-reality glasses equipped with a video camera, and a waist-worn processing unit that runs AI algorithms. After a vitrectomy to clear the eye’s gel-like material, surgeons insert the ultra-thin microchip under the central retina.
The glasses capture live video, which is projected via near-infrared light onto the chip. The chip then converts the signal into electrical impulses sent through the optic nerve to the brain. Patients undergo months of rehabilitation to train their vision-processing brain circuits.
According to the developer, no participant experienced a decline in remaining peripheral vision, a critical advantage of the system’s design.
Clinical Results and Patient Experiences
In the trial, which spanned 17 hospital sites in the UK, France, Italy, the Netherlands, and Germany, patients who had essentially lost their central vision achieved meaningful functional improvements.
One UK patient, 70-year-old Sheila Irvine, described reading again: “Before receiving the implant, it was like having two black discs in my eyes… I was an avid bookworm and I wanted that back.”
Lead UCL researcher Mahi Muqit commented, “In the history of artificial vision, this represents a new era. Blind patients are actually able to have meaningful central vision restoration, which has never been done before.”
Why It’s a Major Breakthrough
Geographic atrophy in dry AMD affects over 5 million people globally and until now has had no approved treatment that restores meaningful central vision. The PRIMA system’s success marks the first time reading ability has been recovered for this condition. Moreover, the implant’s surgical procedure is reported to be under two hours and can be performed by any trained vitreoretinal surgeon, significantly expanding access potential.
Limitations and Future Challenges
Despite the encouraging outcomes, several caveats remain. The restored vision is currently monochromatic and lower in resolution, and the rehabilitation process is intensive, requiring months of training. Some experts note that the absence of randomized placebo-controlled arms in the trial makes it difficult to fully assess the contribution of motivation and training to the outcomes.
One researcher remarked, “I don’t think we’ll ever be able to restore full 20/20 vision with the implant alone, but we are investigating methods that could further improve people’s quality of life and take them above the threshold for legal blindness.”
Looking Ahead: Broader Horizons for AI Vision Systems
The success of PRIMA opens the door for wider applications of AI-driven implants in vision restoration and neural prosthetics. According to the trial team, future efforts may target other retinal diseases, improve facial recognition capability, and enhance contrast and color vision using advanced AI algorithms.
