First Simultaneous Explantation and Re-Implantation of an Argus II Retinal Prosthesis System

Clinical Progress and Optimization of Information Processing in Artificial Visual Prostheses

Visual prostheses, used to assist in restoring functional vision to the visually impaired, convert captured external images into corresponding electrical stimulation patterns that are stimulated by implanted microelectrodes to induce phosphenes and eventually visual perception. Detecting and providing useful visual information to the prosthesis wearer under limited artificial vision has been an important concern in the field of visual prosthesis. Along with the development of prosthetic device design and stimulus encoding methods, researchers have explored the possibility of the application of computer vision by simulating visual perception under prosthetic vision. Effective image processing in computer vision is performed to optimize artificial visual information and improve the ability to restore various important visual functions in implant recipients, allowing them to better achieve their daily demands. This paper first reviews the recent clinical implantation of different types of visual prostheses, summarizes the artificial visual perception of implant recipients, and especially focuses on its irregularities, such as dropout and distorted phosphenes. Then, the important aspects of computer vision in the optimization of visual information processing are reviewed, and the possibilities and shortcomings of these solutions are discussed. Ultimately, the development direction and emphasis issues for improving the performance of visual prosthesis devices are summarized.

INTRAOPERATIVE OPTICAL COHERENCE TOMOGRAPHY AND ENDOSCOPY-GUIDED EXPLANTATION OF ARGUS II DEVICE

PURPOSE

To describe a surgical approach using intraoperative optical coherence tomography and endoscopy for successful Argus II retinal prosthesis system removal.

METHODS

Retrospective review of a patient undergoing Argus II explantation 8 months after initial implantation.

RESULTS

Successful explantation of the Argus II device was performed in this patient.

CONCLUSION

Explantation of the Argus II device can be a difficult surgery, and intraoperative optical coherence tomography and endoscopy can be used to help avoid potential complications.

Optoelectronic Devices for Vision Restoration

PURPOSE OF REVIEW

The goal is providing an update to the latest research surrounding optoelectronic devices, highlighting key studies and benefits and limitations of each device.

RECENT FINDINGS

The Argus II demonstrated long-term safety after five-year follow-up. Due to lack of tack fixation, subretinal implants appear to displace over time. PRIMA's completed primate trial showed initial safety and potential for improved vision, resulting in ongoing clinical trials Bionic Vision Australia developed a new 44-electrode suprachoroidal device currently in a clinical trial. Orion (cortical stimulation) is currently undergoing a clinical trial to demonstrate safety.

SUMMARY

Devices using external camera for images are unaffected by corneal or lens opacities but disconnect eye movements from image perception, while the opposite is true for implants directly detecting light. Visual acuity provided by devices is more complicated than implant electrode density and new devices aim to target this with innovative approaches.