Sila Ervin reads text with special glasses after chip implantation. Captured from Moorfields Eye Hospital website. 

Blind patients have partially regained their vision through an international clinical trial involving the implantation of chips in the back of their eyes, the UK's Daily Telegraph reported on the 20th (local time).

Thirty-eight blind patients from five European countries, including the UK, France, Germany, Italy, and the Netherlands, participated in trials for the Prima implant, developed by the US-based biotech company Second Sight Medical Products.

Patients with dry age-related macular degeneration (AMD), also known as geographic atrophy (GA), had a micro-sized photovoltaic chip, about 2 millimeters in size and the thickness of a human hair, inserted beneath their retinas.

Subsequently, the patients wore special glasses with a built-in video camera. This camera converts images into infrared signals and transmits them to the chip in the eye, which then sends the signals to a small, portable processor where the images are enhanced and sharpened.

The processed images are then transmitted through the implant and the optic nerve to the patient's brain, enabling them to regain some of their vision.

The patients underwent several months of training to learn how to interpret this new form of visual information. As a result, 27 out of the 32 who received the chip implant were able to read again using their central vision.

"These were elderly patients who could no longer read, write, or recognize faces due to vision loss," said Professor Mahrub Mukti, a specialist at Moorfields Eye Hospital in London, who led the UK arm of the clinical trial. "They are emerging from darkness and beginning to utilize their vision again."

"This marks a new era in the history of artificial vision," he added. "It is an unprecedented achievement that blind patients can experience a meaningful recovery of their central vision."

Before (left) and after chip implantation. Captured from Moorfields Eye Hospital website. 

Professor Frank Holz, an ophthalmologist at the University of Bonn in Germany and lead author of the study published in The New England Journal of Medicine, stated, "This is the first time we have demonstrated that functional central vision can be restored in patients blinded by geographic atrophy. This implant signifies a paradigm shift in the treatment of late-stage AMD."

The patients who participated in the clinical trial expressed their joy at regaining their sight.

Sila Ervin, 70, who is registered as visually impaired, said that before the chip implantation, she saw two black discs in front of her eyes, making reading and driving impossible.

"I was an avid reader and wanted that life back," she recalled. "At first, I couldn't see anything at all, but one day the edges of the letters started to appear, and then seeing a single letter was incredibly exhilarating."

However, Ervin noted that reading with the special glasses requires immense concentration, and she must keep her head still to prevent the image from shaking, so she does not use the device outdoors.

The Prima implant has not yet received full approval and is only available through clinical trials. Its future cost also remains uncertain.

Professor Mukti expressed hope that the technology could be available through the UK's National Health Service (NHS) within the next few years. However, the BBC reported that individuals with congenital visual impairments may not benefit from this implant as they lack functional optic nerves to transmit signals to the brain.

Yonhap News Agency