Preliminary 6 month results from the argus^tm ii epiretinal prosthesis feasibility study

Abstract

The Argus™ II 60 channel epiretinal prosthesis has been developed in order to provide partial restoration of vision to subjects blinded from outer retinal degenerative disease. To date the device has been implanted in 21 subjects as part of a feasibility study. In 6 month post-implantation door finding and line tracking orientation and mobility testing, subjects have shown improvements of 86% and 73%, respectively, for system on vs. system off. In high-contrast Square Localization tests using a touch screen monitor 87% of tested subjects performed significantly better with the system on compared with off. These preliminary results show that the Argus II system provides some functional vision to blind subjects.

Use of the Argus II Retinal Prosthesis to Improve Visual Guidance of Fine Hand Movements

“…3 As demonstrated by Humayun et al, prostheses with at most 60 functioning electrodes are sufficient to improve the pointing ability of blind patients. 3 While pointing demonstrates some degree of hand-eye coordination, guiding continuous hand movement based on visual input may provide a better measure of hand-eye coordination ability. For pointing, one must be able to determine the position of an object and use that information to guide a single motor command.…”

“…1 Individuals suffering outer retinal blindness, such as late stage retinitis pigmentosa (RP) or dry age-related macular degeneration, may be able to recover some visual feedback with use of a retinal prosthesis. [2][3][4] These devices stimulate the remaining cells in the inner retina to convey signals to the visual cortex. In theory, stimulating remaining cells in a pattern corresponding to visual stimuli could create visual percepts resembling those stimuli.…”

“…5 Since then, multiple studies conducted during long-term clinical trials of retinal prostheses have demonstrated that these devices can, indeed, provide some benefit in the realms of visual acuity, 6 object and letter recognition, 7,8 and orientation and mobility. 3 Research into hand-eye (or hand-visual prosthesis) coordination for subjects with retinal prostheses, however, is confined mostly to simulations [9][10][11][12][13] and pointing tasks. 3 As demonstrated by Humayun et al, prostheses with at most 60 functioning electrodes are sufficient to improve the pointing ability of blind patients.…”

“…3 Research into hand-eye (or hand-visual prosthesis) coordination for subjects with retinal prostheses, however, is confined mostly to simulations [9][10][11][12][13] and pointing tasks. 3 As demonstrated by Humayun et al, prostheses with at most 60 functioning electrodes are sufficient to improve the pointing ability of blind patients. 3 While pointing demonstrates some degree of hand-eye coordination, guiding continuous hand movement based on visual input may provide a better measure of hand-eye coordination ability.…”

Study of Al-doped ZnO Transparent Stimulus Electrode for Fully Implantable Retinal Prosthesis with Three-dimensionally Stacked Retinal Prosthesis Chip

“…(8)(9)(10)(11)(12)(13) Figure 2 shows configurations of an epiretinal stimulation and a subretinal stimulation with the 3D stacked retinal prosthesis chip. The 3D stacked retinal prosthesis chip receives incident light and converts it into a biphasic stimulus current train, and the stimulus electrode array stimulates the remaining retinal cells.…”