Implantation and long-term assessment of the stability and biocompatibility of a novel 98 channel suprachoroidal visual prosthesis in sheep
Open accessAbstract
Severe visual impairment can result from retinal degenerative diseases such as retinitis pigmentosa, which lead to photoreceptor cell death. These pathologies result in extensive neural and glial remodelling, with survival of excitable retinal neurons that can be electrically stimulated to elicit visual percepts and restore a form of useful vision. The Phoenix99 Bionic Eye is a fully implantable visual prosthesis, designed to stimulate the retina from the suprachoroidal space. In the current study, nine passive devices were implanted in an ovine model from two days to three months. The impact of the intervention and implant stability were assessed using indirect ophthalmoscopy, infrared imaging, and optical coherence tomography to establish the safety profile of the surgery and the device. The biocompatibility of the device was evaluated using histopathological analysis of the tissue surrounding the electrode array, with a focus on the health of the retinal cells required to convey signals to the brain. Appropriate stability of the electrode array was demonstrated, and histological analysis shows that the fibrotic and inflammatory response to the array was mild. Promising evidence of the safety and potential of the Phoenix99 Bionic Eye to restore a sense of vision to the severely visually impaired was obtained.
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Suprachoroidal prostheses have good mechanical stability without fixation with retinal tacks and, like epiretinal prostheses, good heat dissipation capacity and allow the insertion of large arrays.
“Like subretinal prostheses, they have good mechanical stability without fixation with retinal tacks [56,58] and, like epiretinal prostheses, they have good heat dissipation capacity and allow the insertion of large arrays [57].”
From Advances in visual prostheses: engineering and biological challenges (2022) · cites this paper as [56]
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- Authors
- Eggenberger, S. C., James, N. L., Ho, C., Eamegdool, S. S., Tatarinoff, V., Craig, N. A., Gow, B. S., Wan, S., Dodds, C. W. D., La Hood, D., Gilmour, A., Donahoe, S. L., Krockenberger, M., Tumuluri, K., da Cruz, M. J., Grigg, J. R., McCluskey, P., Lovell, N. H., Madigan, M. C., Fung, A. T., & Suaning, G. J.
- Affiliations
- The University of Sydney (AU)
- UNSW Sydney (AU)
- Westmead Institute for Medical Research (AU)
- ORCID
- Venue
- Biomaterials
- Publisher
- Elsevier BV
- Published
- 2021-12
- Volume
- 279
- Pages
- 121191
- ISSN
- 0142-9612 (ISSN-L)
- OpenAlex
- W3208381810
- Cited by
- 21
- References
- 45
- Citations by year
- 2026: 5 · 2025: 8 · 2024: 1 · 2023: 4 · 2022: 2 · 2021: 1
- FWCI
- 0.92
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- Biomaterials (publishedVersion, cc-by)
- PubMed (publishedVersion)
- The Sydney eScholarship Repository (The University of Sydney) (submittedVersion, cc-by)
- UNSWorks (University of New South Wales, Sydney, Australia) (submittedVersion, cc-by)
- Topics
- Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neuroscience and Neural Engineering
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Retinal Development and Disorders
- Health Sciences › Medicine › Surgery › Tissue Engineering and Regenerative Medicine
- Keywords
- retinal prosthesis, retinitis pigmentosa, retinal degeneration, biocompatibility, fibrosis, inflammation, sheep model, vision restoration, implant safety
- MeSH terms
- Animals, Electrodes, Implanted, Retina, Retinitis Pigmentosa, Sheep, Prosthesis Implantation, Tomography, Optical Coherence, Visual Prosthesis
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