Visual Prosthesis — Combined Overview (Retina + LGN + Cortex)
Umbrella hub for the visual-prosthetics family of brain-computer-interface. Any implantable system that replaces lost photoreceptors/optic-path function to restore vision — whether it interfaces the residual retina or the visual cortex itself.
The two families
| Retinal prostheses | Cortical (cortex) prostheses | |
|---|---|---|
| Target | Retina (epiretinal / subretinal / suprachoroidal) | Visual cortex (V1; surface, intracortical, or LGN) |
| Principle | Stimulate surviving bipolar/RGCs | Stimulate neurons to elicit phosphenes |
| Requirement | Healthy inner retina (bipolar/RGCs) | Intact visual cortex only — bypasses eye and optic nerve |
| Indications | GA / AMD, RP, Stargardt | Any cause of blindness incl. optic-nerve damage; totality of blindness |
| Resolution (2026) | PRIMA 378 px; form vision demonstrated (reading) | Orion 60 ch (phosphene vision, 6-yr data); 1,000+ ch in animals (1024-ch monkey study) |
| Maturity | Commercial (PRIMA, CE-marked EU 2026) | Clinical/preclinical (No commercial device yet) |
| Pages | retinal-prosthesis, retinal-prosthesis-companies | cortical-visual-prosthesis, cortical-visual-prosthesis-companies |
Shared design language
All modern systems converge on the same architecture: **camera glasses + processor
- wireless power/telemetry + electrode array** (or photovoltaic chip), producing phosphene-based artificial vision. Key concepts: form vision (integration of elements into percepts — first demonstrated by PRIMA; also via dynamic stimulation in cortex), topographic phosphene mapping, and visual learning (the brain must learn to interpret stimulation).1
Strategic debate: retina-first vs cortex-universal
- Retina-first (science-corp/max-hodak): simple structure, controllable surgery, clear population (GA/AMD >5M), fastest regulatory + commercial path — the only approach with a CE-marked, commercially available form-vision device (Jul 2026).
- Cortex-universal (neuralink Blindsight, ReVision Implant, Monash Gennaris): universal applicability (“performance trumps invasiveness” — every completely blind person spoken to said they don’t mind where the implant goes, they just want something that works), but surgery is deeper, channel count is still far below useful resolution (1,000–2,000 electrodes estimated needed), and no company has commercialized yet.2
- LGN route (phosphoenix): targets the retinotopic relay (LGN) — compact size, clinically accessible deep-brain target; retains intrinsic visual structure in that form and motion )P+M+K) streams are seperated in the laminar structure, allowing a cell-specific targetting without the need for current steering etc. There is a strong argument the LGN is a better target than the cortex…
Timeline snapshot (Aug 2026)
- 2000s–2010s: Retinal devices commercialized (Argus II 2011 CE/2013 FDA; Alpha AMS 2013 CE), both later abandoned.
- 2020: Chen et al. (Science) — 1024-channel cortical prosthesis in monkeys; monkey immediately recognized shapes/motion/letters.3
- 2021: First modern human cortical implant (96 electrodes, UMH Elche, Spain — patient Berna Gomez).
- 2024: Science Corp. acquires PRIMA; Blindsight FDA Breakthrough designation.
- 2025: PRIMA NEJM (form vision in humans), Orion 5-year EFS results; Cortigent S-1 filed.
- 2026: PRIMA CE mark + EU commercial launch (Jul); Orion 6-year EFS results (NANS); ReVision Implant €4M + FDA Breakthrough + FIH approved; Phosphoenix fundraising + LGN pivot; Blindsight human trials expected ~2026. Adjacent smart-contact-lens: azalea-vision wins EIC Accelerator (Jul, €7.5M) to move its ALMA lens into clinical development.
Adjacent technology: smart contact lenses
Not all vision-restoration-adjacent work implants. Smart contact lenses are a fast-moving non-implantable category: the lens itself carries adaptive optics, microelectronics and connectivity to correct/adapt vision (clinically: presbyopia, keratoconus, irregular corneas, photophobia) and to sense tear biomarkers. The leading European example is azalea-vision (Belgium, imec/Ghent University spin-off, 2021), which won the EIC Accelerator in July 2026 (up to €7.5M: €2.5M grant + planned €5M EIC Fund equity) to take its ALMA lens into clinical development. Unlike prostheses, these devices correct existing optics rather than replacing photoreceptor/optic-path function — see azalea-vision for details and caveats.4
Related pages
- retinal-prosthesis — retinal subcategory
- cortical-visual-prosthesis — cortex subcategory
- retinal-prosthesis-companies, cortical-visual-prosthesis-companies — schemas
- science-corp, phosphoenix, revision-implant, cortigent, neuralink, pieter-roelfsema
- visual-prosthesis-patents — patent-level IP landscape (per-patent summaries)
- azalea-vision — adjacent smart contact lens platform (non-implantable)
References
- Science Corp. NEJM/CE-mark releases (2025–2026); Vivani/Cortigent NANS 2026 release.
- Horizon Magazine (EU, 2023): NeuraViPeR & HyperStim projects; electrode-count estimates.
- Chen X, et al. Science 370(6521):1191-1196 (2020).
- Azalea Vision press release, Business Wire, 1 July 2026 (smart contact lens, EIC Accelerator).