Elsevier

Ophthalmology

Volume 119, Issue 4, April 2012, Pages 779-788
Ophthalmology

Original article
Interim Results from the International Trial of Second Sight's Visual Prosthesis

https://doi.org/10.1016/j.ophtha.2011.09.028Get rights and content

Purpose

This study evaluated the Argus II Retinal Prosthesis System (Second Sight Medical Products, Inc., Sylmar, CA) in blind subjects with severe outer retinal degeneration.

Design

Single-arm, prospective, multicenter clinical trial.

Participants

Thirty subjects were enrolled in the United States and Europe between June 6, 2007, and August 11, 2009. All subjects were followed up for a minimum of 6 months and up to 2.7 years.

Methods

The electronic stimulator and antenna of the implant were sutured onto the sclera using an encircling silicone band. Next, a pars plana vitrectomy was performed, and the electrode array and cable were introduced into the eye via a pars plana sclerotomy. The microelectrode array then was tacked to the epiretinal surface.

Main Outcome Measures

The primary safety end points for the trial were the number, severity, and relation of adverse events. Principal performance end points were assessments of visual function as well as performance on orientation and mobility tasks.

Results

Subjects performed statistically better with the system on versus off in the following tasks: object localization (96% of subjects), motion discrimination (57%), and discrimination of oriented gratings (23%). The best recorded visual acuity to date is 20/1260. Subjects' mean performance on orientation and mobility tasks was significantly better when the system was on versus off. Seventy percent of the patients did not have any serious adverse events (SAEs). The most common SAE reported was either conjunctival erosion or dehiscence over the extraocular implant and was treated successfully in all subjects except in one, who required explantation of the device without further complications.

Conclusions

The long-term safety results of Second Sight's retinal prosthesis system are acceptable, and most subjects with profound visual loss perform better on visual tasks with system than without it.

Financial Disclosure(s)

Proprietary or commercial disclosure may be found after the references.

Section snippets

Statement of Compliance

This multicenter feasibility study for Second Sight's retinal prosthesis system is being conducted in accordance with the Declaration of Helsinki and the national regulations for medical device clinical trials in the countries in which the study is being conducted. The study has been approved by the national ministries of health in these countries and the ethics committees or institutional review boards of participating institutions. All subjects signed informed consent to participate. The

Surgery

If the subjects' eyes did not have equal visual acuity at baseline, implantation was performed in the worse-seeing eye. If the subjects' eyes had equal visual acuity, the right eye was selected for implantation. Twenty-six subjects were implanted in the right eye, and 4 were implanted in the left eye.

During the implantation procedure, 67% of subjects had their natural lens removed via clear cornea phacoemulsification (with the exception of pars plana lensectomy in 2 cases) and they were left

Discussion

This study represents 45.6 cumulative subject-years in 30 human subjects implanted with the Argus II Retinal Prosthesis System. There are no other suitable retinal prostheses with which the safety or efficacy of this system can be compared. Although other retinal prostheses currently are being developed by both commercial and academic entities, none of these devices are commercially approved, none are approved for longer than 1 month's implantation, few are even being subject to clinical trial

Acknowledgment

The authors thank Suber Huang, MD, the independent medical safety monitor for this study.

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  • Cited by (551)

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    Manuscript no. 2011-408.

    The members of the Argus II Study Group are listed in Appendix 1 (available online at http://aaojournal.org).

    Financial Disclosure(s): Mark S. Humayun - Equity owner - Second Sight Medical Products, Inc.; Employee - an institution that receives funds from Second Sight Medical Products, Inc.

    Jessy D. Dorn - Employee and Equity owner - Second Sight Medical Products, Inc.

    Robert J. Greenberg - Employee and Equity owner - Second Sight Medical Products, Inc.

    Aries Arditi - Consultant - Second Sight Medical Products, Inc.; Employee - an institution that receives funds from Second Sight Medical Products, Inc.

    Artur V. Cideciyan - Employee - an institution that receives funds from Second Sight Medical Products, Inc.

    Lyndon da Cruz - Employee - an institution that receives funds from Second Sight Medical Products, Inc.

    Gislin Dagnelie - Employee - an institution that receives funds from Second Sight Medical Products, Inc.

    Dean Eliott - Employee - an institution that receives funds from Second Sight Medical Products, Inc.

    Eugene Filley - Employee - an institution that receives funds from Second Sight Medical Products, Inc.

    Avinoam B. Safran - Employee - an institution that receives funds from Second Sight Medical Products, Inc.

    José-Alain Sahel - Employee - an institution that receives funds from Second Sight Medical Products, Inc.

    Supported by the National Institutes of Health, Bethesda, Maryland (grant no.: 5R01EY012893-10 [RJG]). Sponsored by Second Sight Medical Products, Inc., Sylmar, California. The sponsor participated in the design of the study, conducting the study, data collection, data management, data analysis, interpretation of the data, preparation, and review of the manuscript.

    Group members listed online in Appendix 1 (available at http://aaojournal.org).

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