gms | German Medical Science

Artificial Vision 2019

The International Symposium on Visual Prosthetics

13.12. - 14.12.2019, Aachen

Development of a cortical visual neuroprosthesis for the blind: preliminary results in human

Meeting Abstract

Suche in Medline nach

  • Eduardo Fernandez - University Miguel Hernández, Bioengineering Institute, Elche/E

Artificial Vision 2019. Aachen, 13.-14.12.2019. Düsseldorf: German Medical Science GMS Publishing House; 2019. Doc19artvis34

doi: 10.3205/19artvis34, urn:nbn:de:0183-19artvis347

Veröffentlicht: 10. Dezember 2019

© 2019 Fernandez.
Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). Lizenz-Angaben siehe http://creativecommons.org/licenses/by/4.0/.


Gliederung

Text

Objective: Cortical prostheses are a subgroup of visual neuroprostheses capable of evoking visual percepts in profoundly blind people through direct electrical stimulation of the occipital cortex. This approach may be the only treatment available for blindness caused by glaucoma, end-stage retinal degenerations, optic atrophy or trauma to the retina and/or optic nerves.

Materials and methods: A 57-year-old female with bilateral optic neuropathy and no light perception for 16 years was implanted for 6 months with an array of 100 intracortical microelectrodes based on the Utah Electrode Array (UEA). The UEA was implanted in the right visual cortex, nearby the occipital pole (O1). We collected multielectrode recordings and descriptive feedback regarding thresholds, features of evoked perceptions and stimulation parameters to investigate if the volunteer could integrate the electrical stimulation of visual cortex into meaningful perceptions. All the experiments were carried out at the Hospital IMED Elche during the early post-surgical period and, afterward, in a human neurophysiology laboratory at the Miguel Hernández University (Spain).

Results: The surgical implantation was performed without complications and high-quality simultaneous recordings were consistently obtained. It was necessary a training period until the subject was able to distinguish between natural (spontaneous phosphenes) and artificial visual perceptions. Microstimulation mainly evoked elementary phosphenes at stable locations in visual space, described as isolated and spatially localized spots of light. All the phosphenes were in the left visual field. When several electrodes were stimulated simultaneously the subject reported the perception of complex patterns. No adverse effects have been reported to date.

Discussion: Our preliminary results are very encouraging in terms of the feasibility of a cortical visual prosthesis, and suggest that electrical microstimulation of occipital cortex in long-term blind individuals is able to provide meaningful visual perceptions. However, there are still a relevant number of open questions and more experiments should be done.