The chip that could cure blindness: ‘Pioneering’ device the size of a grain of SAND restores reading vision to people with sight-loss

A tiny chip the size of a grain of sand implanted in the back of the eye can effectively restore vision loss, scientists reveal.

Measuring just 2mm x 2mm, the ‘pioneering’ implant is paired with a special pair of augmented reality (AR) glasses, equipped with a camera.

In experiments, patients who had lost their sight to age–related macular degeneration (AMD) were able to read once again.

Sheila Irvine was one of the first patients to receive the implant, and described being able to see again as ‘dead exciting’.

‘It was dead exciting when I began seeing a letter,’ the patient at Moorfields Eye Hospital said. 

Study author Professor Mahi Muqit, ophthalmologist at University College London^[1], called it a ‘new era’ in the history of artificial vision. 

‘Blind patients are actually able to have meaningful central vision restoration, which has never been done before,’ said Professor Muqit. 

‘Getting back the ability to read is a major improvement in their quality of life, lifts their mood and helps to restore their confidence and independence.’ 

Measuring just 2mm x 2mm, the ‘pioneering’ implant is paired with a special pair of augmented reality (AR) glasses, equipped with a camera

The chip – which, at 0.03mm thick is about half the width of a human hair – has been built by Science Corporation, a California–based firm started by Max Hodak, who also co–founded Neuralink with Elon Musk. 

In an operation lasting under two hours, it is implanted in the retina – a layer at the back of the eye which detects light and converts it into signals for the brain.

Patients wear a special pair of AR glasses that has a camera in front of the eye piece to detect light reflected off objects. 

This visual information is then transmitted from the glasses to a handheld computer, which translates it into infrared patterns.

In turn, the infrared is transmitted back to the glasses and projected into the patient’s eye, where it hits the chip at the back. 

When it hits the retinal implant, the infrared light is transmitted to electrical signals that pass through eye cells into the brain, where it is interpreted as vision. 

Lastly, a zoom feature on a tethered handheld computer, which looks like a TV remote, gives patients the ability to magnify letters. 

To test the system, the international team recruited 38 patients in 17 hospital sites across five countries, including Moorfields Eye Hospital in London. 

Sheila Irvine was one of the first patients to receive the implant, and described being able to see again as ‘dead exciting’ 

In trials, participants were able to read letters, numbers and words using the prosthetic vision system. Pictured, image of the electronic chip in a patient’s eye

Left: Simulation of a patient’s vision with macular degeneration. Right: Simulation of the patient’s vision enhanced with the device

All patients had lost complete sight in their eye due to AMD, which is due to light–sensitive retinal cells dying of over many years. 

Around a month or so after the operation, the new chip was activated and participants began a ‘rehabilitation process’ intended to ‘train’ the eye to get used to the system. 

As part of this, patients were encouraged to explore ways of using the device, such as doing puzzles and crosswords and even navigating the Paris Metro.

A year after the operation, 84 per cent of participants (27 out of 32) saw a ‘clinically meaningful improvement in visual acuity’ and were able to read letters, numbers and words at home using the system.  

Those treated with the device could also read, on average, five lines of a vision chart; some participants could not even see the chart before their surgery. 

Ms Irvine described life with AMD as ‘like having two black discs in my eyes’. 

She said: ‘I was an avid bookworm, and I wanted that back. I was nervous, excited, all those things. 

‘There was no pain during the operation, but you’re still aware of what’s happening.’

Currently, there is there is no treatment licensed for dry AMD, the most common form of AMD that can result in severe loss of central vision. 

But the new findings, published in The New England Journal of Medicine^[2], pave the way for seeking approval to market the device, which is the first to enable people to read letters, numbers and words through an eye that had lost its sight.

Members of the public with AMD could get this implant on the NHS as soon as 2027, according to Professor Muqit. 

The team admits there serious are adverse effects relating to the implantation procedure, such as retinal detachment and ocular hypertension, but says that overall the ‘benefits of the PRIMA system outweighed the risks of implantation’. 

‘These are elderly patients who were no longer able to read, write or recognise faces due to lost vision,’ said Professor Muqit. 

‘They’ve gone from being in darkness to being able to start using their vision again.

‘Getting back the ability to read is a major improvement in their quality of life, lifts their mood and helps to restore their confidence and independence.’