Artificial vision – successes and challenges

Retina Implant AG was at “The Eye & The Chip – World Congress on Artificial Vision” in Detroit, USA, to showcase research results relating to its subretinal implant. The annual congress is organised by the Detroit Institute of Ophthalmology, which is part of the Henry Ford Hospital. The event is a forum for interdisciplinary collaboration between specialists from across the world and focuses on advances in nanoelectronics and neurobiology that relate to “artificial vision”.

The subretinal implant from Retina Implant AG can help patients who perceive very little or no light as a result of the degenerative disease retinitis pigmentosa to regain a certain degree of useful sight. Most patients with an implanted chip can identify light sources, which makes it easier for them to find their way around a room again. In his presentation at the congress, Dr. Alfred Stett, CTO of Retina Implant AG, described the design features of the subretinal implant to the assembled international specialists. The latest generation of the chip, the RETINA IMPLANT Alpha AMS, has virtually no externally visible electronic components. Only a small transponder that connects with the chip’s external power supply is embedded under the skin behind the ear. The chip is only around 12 square millimetres in size and is placed directly below the fovea centralis, which means it can move with the eye. This allows patients to use natural (previously learned) eye movement to locate objects. Prof. Eberhart Zrenner, Senior Professor of Ophthalmology at the Werner Reichardt Centre for Integrative Neurosciences, which is part of the Institute for Ophthalmic Research at Eberhard Karls Universität Tübingen, presented the results of the latest clinical study 1 (“Interim Results of a Multicenter Trial with the New Electronic Subretinal Implant Alpha AMS in 15 Patients Blind from Inherited Retinal Degenerations”).

Dr. Günther Zeck from the Natural and Medical Sciences Institute (NMI) at the University of Tübingen gave a presentation entitled “Single-Pixel Stimulation of Blind Rodent Retina Using a Subretinal Implant”, in which he described how he uses the chip under laboratory conditions for his research into electrical stimulation of the retina. The presentations, which covered the full spectrum from basic research and technology to clinical studies was debated intensively by the scientific community. “This congress brings together all the working groups around the world that are studying ‘artificial vision using implants’,” explained Dr. Stett. “Scientists, doctors, engineers and manufacturers report on their achievements – and the challenges that still need to be overcome.” A great emphasis was placed on two key elements – firstly, the need for uniform test methods for measuring the quality of vision and, secondly, ensuring the effectiveness of the various treatment approaches can be compared. The congress delegates also agreed on the importance of applying strict selection criteria when determining which patients are suitable candidates for an implant and on the high value of intensive training after implantation.