title: Ten-Year Follow-up of a Blind Patient Chronically Implanted with Epiretinal Prosthesis Argus I.
abstract: OBJECTIVE
  The Argus I implant is the first-generation epiretinal prosthesis approved for an investigational clinical trial by the United States Food and Drug Administration. Herein we report testing results obtained from a 10-year follow-up to study the physiologic effects of the bioelectronic visual implant after prolonged chronic electrical stimulation.
  
  
  METHODS
  Case report.
  
  
  METHODS
  One man, 55 years of age when enrolled in the study, underwent surgical implantation of the Argus I in June 2004, followed by periodic tests from July 2004 through June 2014, spanning a total of 10 years.
  
  
  METHODS
  The decade-long follow-up consisted of implant system performance tests, subject visual function evaluation, and implant-retina interface analysis.
  
  
  METHODS
  Changes in electrode impedance and perceptual threshold over the time course; subject's performance on visual function task, orientation, and mobility tests; and optical coherence tomography data, fundus imaging, and fluorescein angiography results for the assessment of subject's implant-retina physical interface.
  
  
  RESULTS
  Electrically elicited phosphenes were present 10 years after implantation of an epiretinal stimulator. The test subject not only was able to perceive phosphenes, but also could perform visual tasks at rates well above chance.
  
  
  CONCLUSIONS
  This decade-long follow-up report provides further support for the use of retinal prostheses as a long-lasting treatment for some types of blindness.
authors.affiliation: Department of Ophthalmology, Keck School of Medicine, University of Southern California, Los Angeles, California.
authors.forename: Lan
authors.initials: L
authors.lastname: Yue
authors.affiliation: Department of Ophthalmology, Keck School of Medicine, University of Southern California, Los Angeles, California; Department of Ophthalmology and Visual Sciences, Federal University of São Paulo (UNIFESP), São Paulo, Brazil.
authors.forename: Paulo
authors.initials: P
authors.lastname: Falabella
authors.affiliation: Second Sight Medical Products, Inc, Sylmar, California.
authors.forename: Punita
authors.initials: P
authors.lastname: Christopher
authors.affiliation: Second Sight Medical Products, Inc, Sylmar, California.
authors.forename: Varalakshmi
authors.initials: V
authors.lastname: Wuyyuru
authors.affiliation: Second Sight Medical Products, Inc, Sylmar, California.
authors.forename: Jessy
authors.initials: J
authors.lastname: Dorn
authors.affiliation: Department of Ophthalmology and Visual Sciences, Federal University of São Paulo (UNIFESP), São Paulo, Brazil.
authors.forename: Paulo
authors.initials: P
authors.lastname: Schor
authors.affiliation: Second Sight Medical Products, Inc, Sylmar, California.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Greenberg
authors.affiliation: Department of Ophthalmology, Keck School of Medicine, University of Southern California, Los Angeles, California.
authors.forename: James D
authors.initials: JD
authors.lastname: Weiland
authors.affiliation: Department of Ophthalmology, Keck School of Medicine, University of Southern California, Los Angeles, California. Electronic address: humayun@med.usc.edu.
authors.forename: Mark S
authors.initials: MS
authors.lastname: Humayun
mesh_terms: D001766:Blindness / Q000503:physiopathology / Q000534:rehabilitation*; D017097:Electric Impedance; D004567:Electrodes, Implanted; D005451:Fluorescein Angiography; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010719:Phosphenes / Q000502:physiology*; D019919:Prosthesis Implantation; D012160:Retina / Q000503:physiopathology*; D012684:Sensory Thresholds; D035703:Therapies, Investigational; D041623:Tomography, Optical Coherence; D014796:Visual Perception / Q000502:physiology*; D057488:Visual Prosthesis