• Online Features  This Article  • Full text  • PDF  • Reply to article  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Citation map  • Citing articles on HighWire  • Citing articles on Web of Science (27)  • Contact me when this article is cited  Related Content  • Similar articles in this journal  Topic Collections  • Retinal/ Chorioretinal Disorders  • Prostheses/ Implants  • Alert me on articles by topic  Social Bookmarking   What's this?

Spatial Vision With a 16-Electrode Implant

Avi Caspi, PhD; Jessy D. Dorn, PhD; Kelly H. McClure, MS; Mark S. Humayun, MD, PhD; Robert J. Greenberg, MD, PhD; Matthew J. McMahon, PhD

Arch Ophthalmol. 2009;127(4):398-401.

Objective  To demonstrate that an epiretinal prosthesis can produce patterned visual perception in patients blinded by photoreceptor degeneration who have no other treatment options.

Methods  A totally blind subject with retinitis pigmentosa had a 16-electrode epiretinal prosthesis implanted. The implant is controlled wirelessly by an external computer or a head-mounted video camera. Spatial vision was assessed by measuring the subject's response to direct stimulation of patterns and by comparing the ability of the subject to identify the orientation of gratings with the system on and off.

Results  In response to stimulation of 2 orthogonal rows of electrodes, the subject drew 2 lines with a mean (SEM) angle of 87.4° (1.8°) between them. With the system on, the subject identified the orientation of the grating target up to a spatial resolution that matches the spacing between the adjacent electrodes. In contrast, with the system off, the subject could not detect or identify the target's orientation.

Conclusion  Synchronized stimulation of different retinal locations with an epiretinal prosthesis implanted long-term can produce spatial vision with an acuity level determined by the distance between the electrodes.

Trial Registration  clinicaltrials.gov Identifier: NCT00279500

Author Affiliations: Second Sight Medical Products, Inc, Sylmar (Drs Caspi, Dorn, Humayun, Greenberg, and McMahon and Mr McClure) and Doheny Eye Institute, Los Angeles (Dr Humayun), California.

CiteULike    Connotea    Delicious    Digg    Facebook    Reddit    Technorati    Twitter     What's this?

THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES

Frequency and Amplitude Modulation Have Different Effects on the Percepts Elicited by Retinal Stimulation
Nanduri et al.
IOVS 2012;53:205-214.
ABSTRACT | FULL TEXT  

Blind subjects implanted with the Argus II retinal prosthesis are able to improve performance in a spatial-motor task
Ahuja et al.
Br J Ophthalmol 2011;95:539-543.
ABSTRACT | FULL TEXT  

Stimulation with a Wireless Intraocular Epiretinal Implant Elicits Visual Percepts in Blind Humans
Klauke et al.
IOVS 2011;52:449-455.
ABSTRACT | FULL TEXT  

Simulating prosthetic vision: Optimizing the information content of a limited visual display
van Rheede et al.
J Vis 2010;10:32-32.
ABSTRACT | FULL TEXT  

Selective Activation of Neuronal Targets With Sinusoidal Electric Stimulation
Freeman et al.
J. Neurophysiol. 2010;104:2778-2791.
ABSTRACT | FULL TEXT