An innovative combination of an electronic eye implant and augmented reality (AR) glasses has enabled people with severe vision loss to read again. This is according to a European clinical study led by researchers at University College London (UCL) and Moorfields Eye Hospital, the results of which have been published in The New England Journal of Medicine.
More than three-quarters (84%) of the participants regained some form of functional vision after treatment: they were able to read letters, numbers and words again with the eye that had previously been completely blind due to geographic atrophy in dry age-related macular degeneration (AMD). On average, patients were able to read five lines on a visual acuity chart after the operation. And to think that some of them could not even see the chart before the procedure.
The trial, conducted on 38 patients in 17 hospitals in five countries, tested the so-called PRIMA implant, a wireless subretinal photovoltaic implant that functions as a miniature solar panel. The results of the study were published this week in The New England Journal of Medicine.
Implant and AR technology
The surgical procedure takes less than two hours and involves inserting a microchip measuring just 2 by 2 millimetres under the retina. Patients then wear AR glasses with a built-in camera, which records images and projects them onto the implant via infrared light.
An AI system in a small computer attached to the patient's belt processes these images and converts them into electrical signals. These signals are sent via the optic nerve to the brain, where they are interpreted as visual perception. After a few weeks of recovery, the implant is activated and patients undergo intensive rehabilitation to learn how to use their new way of seeing.
‘This marks a new era in artificial vision technology,’ says Prof. Mahi Muqit, vitreoretinal surgeon and researcher at UCL and Moorfields. ‘Patients who were completely blind now have the opportunity to read again. This greatly improves their quality of life and restores not only their vision, but also their self-confidence and independence.’
Also for other eye conditions
Importantly, none of the participants experienced any deterioration in their remaining peripheral vision. The successful results open the door to market approval of the PRIMA system and future use in other eye conditions.
According to Muqit, this is just the beginning: ‘There is currently no approved treatment for dry AMD. In the future, this technology could also be used for multiple forms of blindness. It does require training, but it literally and figuratively gives patients a new perspective.’
Visual brain prosthesis
Earlier this month, we reported on an innovative brain prosthesis being developed by researchers at the Netherlands Institute for Neuroscience, led by Prof. Pieter Roelfsema. This prosthesis can give blind people a form of vision again. The technology connects a camera directly to the visual cortex, where vision occurs. Thousands of electrodes in an implant stimulate specific areas of the brain, allowing users to perceive simple visual shapes such as dots or letters.
The method is primarily intended for people whose optic nerve has been damaged, for example as a result of an accident. Animal research has shown that brain stimulation can lead to recognisable visual patterns, which forms the basis for further clinical applications.
