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This project, funded by Gebert Rüf Stiftung, is supported by the following project partners: Medtronic Chair in Neuroengineering, Center for Neuroprosthetics, Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Switzerland; Hôpital Ophtalmique Jules Gonin, Université de Lausanne, Switzerland
Project no: GRS-035/17
Amount of funding: CHF 300'000
Duration: 04.2018 - 06.2020
Area of activity:
Pilotprojekte, 1998 - 2018
Prof. Diego Ghezzi
Ecole Polytechnique Fédérale de Lausanne
STI IBI_STI LNE
Campus Biotech - B3.03
Chemin des Mines 9
1202 Genève (Schweiz)
- diego.ghezzi@epfl. ch
Blindness affects more than 30 million people worldwide. In the last decade, various visual prostheses were developed to fight blindness in case of retinal dystrophies, such as Retinitis pigmentosa and more recently age-related macular degeneration. Several multi-center clinical trials showed the feasibility of restoring a coarse form of vision with retinal implants, such as single letters discrimination and simple objects recognition. However, several challenges remain open, such as the improvement of visual acuity and the enlargement of the visual field above the thresholds of blindness. An agreed upon strategy to improve visual acuity is to increase the electrode density, while a large visual field could be attained by enlarging the retinal coverage with a larger prosthesis.
The project funded by the Gebert Rüf foundation allowed us to provide an answer to an important open question in the field of retinal prosthesis: how can we increase both visual resolution and visual field with a single implant? We addressed this question by validating a wide-field high resolution epiretinal prosthesis (POLYRETINA) in blind mini-pigs.
What is special about the project?
This project introduced 3 major innovations in the field of retinal prostheses:
1. The POLYRETINA prosthesis represents a major step towards the increase of both visual acuity and visual field with the same implant.
2. It is foldable to limit the scleral incision and it has a hemispherical shape to remain in tight contact with the retina. The hemispherical shape can be customized in order to fit the real eye curvature/shape of a patient. This opens up the possibility to an optimized retinal prosthesis according to personal needs.
3. The shape of the prosthesis and the insertion strategy have been inspired by the widely use intra ocular lenses. An ‘injection’ approach is under development, in order to minimize the complexity of the surgical procedure and to make it implantable virtually by every surgeon.
We have designed a retinal prosthesis (POLYRETINA) that cover a retinal surface of 13 mm in diameter, therefore it could restore up to 43° of visual field. It operates according to a photovoltaic stimulation principle via 10,498 stimulating pixels. POLYRETINA was implanted in blind mini-pigs to show its efficacy. This project enabled the development of a minimally invasive injection procedure to insert POLYRETINA within the eye. Preliminary results suggested that implanted mini-pigs recovered the visually evoked cortical potentials upon light stimulation of the POLYRETINA device. These results suggested that POLYRETINA can be efficiently used to restore artificial vision in blindness.
M.J.I. Airaghi Leccardi, N.A.L. Chenais & D. Ghezzi (2020) “Tailored polymeric, photovoltaic, and near-infrared-responsive neuroprosthesis”, Communications Materials 1, 21.
Persons involved in the project
Last update to this project presentation 30.06.2020