Prima Retinal Implant: Subretinal Vision Prosthesis Restoring Central Vision

Short Summary

This video explains the placement of the Prima retinal implant under the retina to replace lost photoreceptors in the central visual field. The procedure begins with illumination for the surgeon, removal of vitreous fluid, and creation of a space beneath the retina. A delivery tool primes the implant for precise insertion, after which it is positioned in the subretinal space. Fluid is injected to reposition the retina, and the device is tuned to align with the central vision. The implant sits below the bipolar cells where photoreceptors have atrophied. For users with limited central vision, glasses with an embedded camera capture the environment and transmit light to the eye using near infrared wavelengths. The implant converts this light into targeted retinal stimulation, mirroring patterns of natural central vision.

Overview

The video details a subretinal vision restoration approach using the Prima retinal implant. It explains how surgical access is created below the retina, how the implant is prepared and inserted, and how the retina is re-positioned to ensure accurate targeting of the central visual field. The system aims to replace degenerated photoreceptors by leveraging native retinal circuitry.

Anatomy and Target

Prima targets the retinal layers, with the implant resting under the bipolar cells in place of damaged photoreceptors. This placement seeks to stimulate the retina as close as possible to its natural processing center, enabling more faithful visual signals to be produced in the central field of view.

Surgical Workflow

The procedure starts with a light aid for the surgeon, followed by removal of vitreous fluid. A space is created beneath the retina to house the implant. The delivery tool primes and inserts the implant into the subretinal space. Fluid is then injected to reposition the retina, and finally the implant is adjusted to optimize central vision coverage. Each step is designed to ensure precise placement and stable contact with the target retinal cells.

Vision Restoration Mechanism

With conventional glasses that embed a camera, environmental light is gathered and transmitted to the eye via near infrared light. The Prima implant accepts this light and stimulates the retina in the same patterned manner, effectively translating environmental scenes into neural signals that the brain can interpret as vision in the central field. This approach aims to recreate useful central vision even when natural photoreceptors have degraded.

Clinical Implications and Future Outlook

The technology represents a pathway toward restoring functional central vision for people affected by photoreceptor loss. Ongoing refinement of placement accuracy, stimulation patterns, and integration with head-mounted cameras could expand the range of everyday tasks that users can perform.