In August, it will be a year since the first commercial IRIS®II retinal chip implantation in Europe took place; it has allowed a blind patient from the IMO to perceive light stimuli and use it to locate objects, meaning that she can be more independent. After the procedure, performed by Dr Borja Corcóstegui, retina specialist and director of the institute, who was involved in the trial and has been involved in the development of bionic vision for over 20 years, the patient began a six-month period of visual rehabilitation involving the clinic and home-based training. This work has made it possible to integrate artificial vision technology, which includes an electrical retinal stimulator with over 150 electrodes, glasses with a bio-inspired mini-camera and a pocket processor, into Rosario Juez’s day-to-day life.
For the patient, blind as the result of retinitis pigmentosa, the retinal chip is another way of supporting her in her daily life, together with her guide dog and the use of a cane. The “threads of colours and lights” that it captures, as she describes them, act as a warning and tell her when there is something in front of her, differentiating shapes and sizes. Some of the first changes she noticed were being “able to tell if there was a plate or glass on the table, whether the TV or lights were on or off, and being able to avoid walking into a wall or an obstacle in the street”.
Retinal chip: more electrodes, higher resolution
Carol Camino, optometrist at the IMO, is responsible for the visual rehabilitation process of learning to “see” bionically; she emphasises the effectiveness of IRIS®II in providing signals that the receptors in the chip, accustomed to darkness, are able to respond to. This improvement in Rosario’s quality of life is supported by the efficiency and safety demonstrated during the multicentre trial that the IMO (the only centre in Spain) participated in and which involved a dozen patients. It was after this, in August 2017, that Rosario received the commercially implanted chip.
Taking stock, as one of the “pioneers” of artificial vision, she asserts “I would repeat the process; it is only the beginning, further improvements are yet to come”. Rosario believes that due to research that has already begun into new models of microchip, light stimuli will be able to sharpen recognition, for example between a tree and a lamppost. This is true of PRIMA, the next generation model that has been developed by the company, Pixium Vision, to succeed IRIS®II. Its first version already has 400 electrodes to help create more defined images.
This promising device, that revolutionises the way electrical retinal stimulators are implanted (by placing them behind the retina instead of on it, so that they can send signals to the brain more biologically), has already been implanted in 5 patients with DMAE as part of a trial in Paris, and is also being tested in Pittsburgh (USA). If the results substantiate it, it is anticipated that over the next few months, a new clinical trial involving various centres will get under way and which the IMO will once again take part in; PRIMA is therefore one step closer to becoming an effective option in the fight against blindness.