09/17/2026
https://www.facebook.com/share/p/1Gx5aKsR1G/
Subretinal Photovoltaic Implant: PRIMA Restores Central Sight in Advanced Geographic Atrophy
What if a tiny wireless photovoltaic implant placed beneath the retina could help restore useful central vision after advanced geographic atrophy has destroyed the photoreceptors responsible for central sight?
That is the concept behind PRIMA, a subretinal photovoltaic retinal implant system developed by Science Corporation.
Unlike conventional approaches to advanced age related macular degeneration, PRIMA does not attempt to regenerate damaged photoreceptors or reverse geographic atrophy.
Instead, it uses a tiny photovoltaic microarray implanted beneath the retina to convert projected near infrared light into electrical stimulation of surviving retinal neurons.
The technology is particularly significant for people with advanced geographic atrophy who have lost functional central vision but retain some peripheral retinal function.
In the PRIMAvera clinical study, 38 patients received the implant. Among the 32 patients assessed at 12 months, 26 patients, approximately 81 percent, achieved a clinically meaningful improvement in visual acuity of at least 0.2 logMAR.
This represents an important development in retinal prosthetic technology because it demonstrates the possibility of generating useful central visual perception through a wireless photovoltaic microchip positioned beneath a damaged macular region.
1️⃣ What Is Geographic Atrophy?
Geographic atrophy is an advanced form of dry age related macular degeneration.
The disease progressively damages the retinal pigment epithelium, photoreceptors and associated outer retinal structures.
When the atrophy involves the fovea, patients can experience severe loss of the central vision required for:
📖 Reading
👁️ Facial recognition
📱 Smartphone use
💻 Detailed computer work
🧾 Reading menus and labels
🎯 Many visually demanding daily activities
Importantly, geographic atrophy does not necessarily destroy the entire retina.
Peripheral retinal regions may continue to function even when the central macula becomes severely damaged.
That remaining retinal architecture creates an opportunity for retinal prosthetic technology.
PRIMA is designed to use this surviving neural circuitry.
2️⃣ How Does the PRIMA Microchip Work?
PRIMA uses a wireless photovoltaic implant positioned beneath the retina in the region affected by geographic atrophy.
The implant contains an array of microscopic photovoltaic pixels.
The implant does not contain a conventional battery.
Instead, the system receives optical energy from specialized glasses.
A camera captures the visual scene.
The visual information is processed and projected toward the implanted photovoltaic array using near infrared light.
The photovoltaic pixels convert that optical energy into electrical stimulation.
That stimulation activates surviving inner retinal neurons and retinal pathways downstream from the damaged photoreceptors.
In simplified form:
Visual scene
↓
Camera
↓
Image processing
↓
Near infrared projection
↓
Photovoltaic pixels
↓
Electrical stimulation
↓
Surviving retinal neurons
↓
Visual perception
The system therefore bypasses missing photoreceptors rather than attempting to biologically regenerate them.
3️⃣ Why Is the Implant Called Photovoltaic?
The word photovoltaic is important.
The microchip converts light energy directly into electrical energy.
This makes PRIMA fundamentally different from a conventional wired retinal prosthesis.
The implanted array does not require a physical electrical cable extending through the eye.
Instead, optical energy is delivered wirelessly through the external visual processing glasses.
The implant can therefore remain extremely small while receiving the energy required to stimulate the retina.
The original PRIMA implant was approximately 2 mm wide and contained 378 photovoltaic pixels, each approximately 100 micrometres in diameter.
4️⃣ What Did the PRIMAvera Trial Show?
The major clinical evidence came from the PRIMAvera prospective multicenter clinical study.
The study enrolled 38 patients with geographic atrophy caused by age related macular degeneration and severe central visual impairment.
At 12 months, 32 patients completed the primary visual assessment.
Among these patients, 26 patients, approximately 81 percent, achieved at least a 0.2 logMAR improvement in visual acuity.
This provides important clinical evidence that a subretinal photovoltaic implant can produce meaningful improvements in central visual function in patients with advanced geographic atrophy.
However, the study population was relatively small and the study was not randomized, so the findings should be interpreted within the context of the study design.
5️⃣ Does PRIMA Restore Normal Human Vision?
This distinction is extremely important.
PRIMA does not regenerate damaged photoreceptors.
It does not reverse geographic atrophy.
And it does not restore completely normal natural central vision.
Instead, it creates a form of prosthetic central vision by electrically stimulating surviving retinal circuitry.
Earlier clinical research demonstrated that patients could perceive patterned prosthetic visual information corresponding to areas affected by central vision loss.
Therefore, the phrase restored vision should be understood clinically as restored functional visual perception through a retinal prosthesis rather than biological regeneration of the macula.
6️⃣ Why Are the Photovoltaic Pixels So Important?
Pixel size determines the spatial resolution that the implant can potentially provide.
The original PRIMA array used approximately 100 micrometre pixels.
That architecture produced prosthetic visual acuity consistent with the spatial limitations of the implant.
Researchers are now investigating smaller photovoltaic pixels that could potentially provide substantially higher prosthetic resolution.
Experimental work has demonstrated photovoltaic arrays with pixels much smaller than the original clinical device.
The long term objective is straightforward:
Smaller pixels
↓
Higher spatial resolution
↓
Potentially finer prosthetic vision
This is one of the most important engineering challenges in retinal prosthetics.
7️⃣ Why Does the Patient Need Special Glasses?
The implanted photovoltaic array does not independently see the surrounding environment.
The external glasses provide both visual information and optical energy.
A camera captures the environment.
A visual processor processes the image.
Near infrared light then projects the processed information onto the subretinal photovoltaic array.
The implant converts those optical signals into electrical stimulation.
The patient therefore uses a hybrid biological and electronic visual system.
The peripheral retina can continue providing natural vision while the implant provides prosthetic central visual information.
Previous research has demonstrated simultaneous perception of natural peripheral vision and prosthetic central vision.
8️⃣ What Happens During Implantation?
PRIMA requires vitreoretinal surgery.
The photovoltaic array is surgically positioned beneath the retina in the region corresponding to the area of geographic atrophy.
The implant therefore sits beneath the degenerated retinal region.
Postoperative imaging can demonstrate the implant on fundus photography and its relationship to the retinal layers using optical coherence tomography.
This procedure is not comparable to receiving an ordinary intraocular lens or using an eye drop.
It is a specialized retinal surgery involving implantation of an electronic device beneath the retina.
Surgical expertise, appropriate patient selection and postoperative visual rehabilitation are therefore important components of the treatment strategy.
9️⃣ What About Safety?
The PRIMAvera study also evaluated procedure related and device related serious adverse events.
Among the 38 implanted participants, 26 serious adverse events occurred in 19 patients.
Most of these events occurred during the early postoperative period.
The study also found that mean natural peripheral visual acuity after implantation was comparable with baseline.
This is clinically important because preservation of useful peripheral natural vision is a major objective of retinal prosthetic systems.
Histopathological research involving eyes containing PRIMA implants has also provided information about the tissue response surrounding the photovoltaic array.
These findings contribute to understanding implant and retinal biocompatibility, although they do not eliminate the risks associated with retinal surgery.
🔟 What Does the Future Look Like?
The current PRIMA technology may represent only the beginning.
The original photovoltaic array demonstrated that optical stimulation of a subretinal implant can generate useful central prosthetic vision.
The next major challenge is resolution.
Researchers are investigating smaller pixels, improved optical projection and increasingly sophisticated image processing.
Future systems could potentially provide:
🔬 Higher visual resolution
🧠 More sophisticated retinal stimulation
👓 Improved image processing
🔍 Better electronic and optical magnification
🎯 More precise stimulation of surviving retinal pathways
The ultimate goal is not simply to make patients perceive light.
It is to make prosthetic vision increasingly useful for real world visual tasks.
1️⃣1️⃣ Is PRIMA Currently an Approved Treatment?
This is an important clinical distinction.
PRIMA remains an investigational medical device and is not currently an FDA approved treatment available for routine clinical use in the United States.
The technology is still undergoing clinical and regulatory development.
The PRIMAvera clinical study provides important evidence supporting the potential of this approach, but regulatory authorization and broader clinical availability remain separate questions.
Therefore, PRIMA should currently be described as a clinically investigated retinal prosthesis rather than an established routine treatment.
1️⃣2️⃣ What Could This Mean for Patients With Advanced Macular Blindness?
The potential significance is enormous.
For a patient who has lost central vision because of advanced geographic atrophy, conventional optical correction cannot restore vision when central photoreceptors and outer retinal structures have been severely destroyed.
A stronger spectacle prescription cannot regenerate the damaged macula.
A conventional contact lens cannot replace lost photoreceptors.
PRIMA takes a fundamentally different approach.
Instead of asking:
How can we make the damaged retina see better?
The technology asks:
Can we bypass the missing photoreceptors and directly stimulate the retinal circuitry that remains?
That conceptual shift is what makes retinal prosthetic technology so important.
🧠 Key Clinical Concept
PRIMA is not a retinal regeneration therapy.
It is a wireless photovoltaic retinal prosthesis.
The implant is positioned beneath the retina within an area affected by geographic atrophy.
External glasses project near infrared light onto the photovoltaic array.
The array converts that optical energy into electrical stimulation.
Surviving retinal neurons then transmit the resulting signals through the remaining visual pathway.
The technology therefore creates a new electronic route into the visual system:
Visual scene
↓
Camera
↓
Processor
↓
Near infrared projection
↓
Photovoltaic chip
↓
Retinal neurons
↓
Brain
The patient can therefore receive prosthetic central visual information while retaining useful natural peripheral vision.
⚠️ Important Clinical Point
The encouraging PRIMA results should not be interpreted as meaning that geographic atrophy has been cured.
PRIMA does not regenerate the retinal pigment epithelium, photoreceptors or normal foveal architecture.
It also requires retinal surgery and specialized external hardware.
The clinical evidence comes from a relatively small study population, and long term safety, durability, accessibility and real world functional benefits remain important areas of continued evaluation.
For now, PRIMA should be regarded as an investigational vision restoration technology with promising clinical evidence rather than a universally available treatment.
👁️ For Eye Care Professionals
PRIMA represents an important convergence of:
🔬 Retinal medicine
⚡ Bioelectronics
🧠 Neuroscience
👁️ Ophthalmic surgery
💻 Computer vision
🤖 Neural interface technology
For optometrists and ophthalmologists, the emergence of retinal prosthetic systems also raises an important future question:
How will low vision rehabilitation change when patients can combine natural peripheral vision with electronically generated central vision?
Future clinical care may involve not only diagnosing retinal disease and prescribing optical aids, but also assessing candidates for retinal prostheses, postoperative visual rehabilitation and adaptation to hybrid natural and prosthetic vision.
🔬 Bottom Line
PRIMA represents a remarkable shift in the treatment concept for advanced geographic atrophy.
Rather than attempting to restore destroyed photoreceptors, the system uses a wireless photovoltaic microarray beneath the retina to electrically stimulate surviving retinal neurons.
In the PRIMAvera study, 26 of 32 patients completing the 12 month assessment achieved a clinically meaningful improvement in visual acuity, while peripheral natural vision remained comparable with baseline.
The technology remains investigational, but the clinical results demonstrate something that was once largely theoretical:
A damaged macular region may be bypassed with an electronic interface capable of generating useful central visual perception.
For patients with advanced geographic atrophy and profound central vision loss, that possibility could mark the beginning of an entirely new era in retinal rehabilitation.
The future of vision restoration may therefore involve not only drugs, gene therapy and cell replacement, but also tiny photovoltaic chips that communicate directly with the surviving retina.
Sources
New England Journal of Medicine | Subretinal Photovoltaic Implant to Restore Vision in Geographic Atrophy Due to AMD
https://www.nejm.org/doi/full/10.1056/NEJMoa2501396
PubMed | Subretinal Photovoltaic Implant to Restore Vision in Geographic Atrophy Due to AMD
https://pubmed.ncbi.nlm.nih.gov/41124203/
ClinicalTrials.gov | PRIMAvera Clinical Study
https://clinicaltrials.gov/study/NCT04676854
Science Corporation | PRIMA Visual Prosthesis
https://science.xyz/technologies/prima
Science Corporation | Company and Clinical Development
https://science.xyz/company
Nature Communications | Enhancing Prosthetic Vision by Upgrade of a Subretinal Photovoltaic Implant in Situ
https://www.nature.com/articles/s41467-025-58084-y
Ophthalmology | Photovoltaic Restoration of Central Vision in Atrophic Age Related Macular Degeneration
https://www.aaojournal.org/article/S0161-6420(20)30189-5/fulltext
PubMed | Photovoltaic Restoration of Central Vision in Atrophic Age Related Macular Degeneration
https://pubmed.ncbi.nlm.nih.gov/32249038/
Ophthalmology Retina | Histologic Findings After Subretinal Implantation of the PRIMA Photovoltaic Array
https://www.sciencedirect.com/science/article/pii/S2468653026002691
