Retinal Prosthesis

Abstract

Retinal prosthesis have been translated from the laboratory to the clinical over the past two decades. Currently, two devices have regulatory approval for the treatment of retinitis pigmentosa. These devices provide partial sight restoration and patients use this improved vision in their everyday lives. Improved mobility and object detection are some of the more notable findings from the clinical trials. However, significant vision restoration will require both better technology and improved understanding of the interaction between electrical stimulation and the retina. This paper reviews the recent clinical trials, highlights technology breakthroughs that will contribute to next generation of retinal prostheses.

Silicon-Integrated High-Density Electrocortical Interfaces

“…However, polymers are susceptible to degradation and are not long-term impermeable to body fluids. While polymer encapsulation has been used for relatively simple and short-term (less than 1-2 years) implants, substantial improvements are needed for viable solutions to long-term hermetic encapsulation [182], [186]. Recent next-generation advances in miniaturized hermetic sealing of silicon integrated circuits, such as multilayer multimaterial coating [187], and encapsulation using liquid crystal polymers (LCPs) [185], are promising developments toward highly miniaturized implantable electronics for chronic clinical use.…”

A Treatise of the Physical Aspects of Phosphenes and Single-Cell Selectivity in Retinal Stimulation

“…Procedure for Single-cell Selectivity: Single-cell selectivity is treated as enhancing the control of the electrodes over single cells to produce an array of independent phosphenes [48]. Thus, the stimulus that spreads through the medium must be constrained to the space required for activation.…”

A Multi-photodiode Array-based Retinal Implant IC with On/off Stimulation Strategy to Improve Spatial Resolution

“…In conventional retinal implants, designed to restore of blind patients by electrical stimulation of surviving inner retinal neurons, the main focus has been on providing a large number of stimulation channels with detailed visual information [1][2][3]. To achieve many stimulation channels, the data rate between the stimulation IC and the electrode array must be maintained high with many interconnection lines.…”