title: An analysis of observer-rated functional vision in patients implanted with the Argus II Retinal Prosthesis System at three years.
abstract: OBJECTIVE
  The purpose of this analysis was to compare observer-rated tasks in patients implanted with the Argus II Retinal Prosthesis System, when the device is ON versus OFF.
  
  
  METHODS
  The Functional Low-Vision Observer Rated Assessment (FLORA) instrument was administered to 26 blind patients implanted with the Argus II Retinal Prosthesis System at a mean follow-up of 36 months. FLORA is a multi-component instrument that consists in part of observer-rated assessment of 35 tasks completed with the device ON versus OFF. The ease with which a patient completes a task is scored using a four-point scale, ranging from easy (score of 1) to impossible (score of 4). The tasks are evaluated individually and organised into four discrete domains, including 'Visual orientation', 'Visual mobility', 'Daily life and 'Interaction with others'.
  
  
  RESULTS
  Twenty-six patients completed each of the 35 tasks. Overall, 24 out of 35 tasks (69 per cent) were statistically significantly easier to achieve with the device ON versus OFF. In each of the four domains, patients' performances were significantly better (p < 0.05) with the device ON versus OFF, ranging from 19 to 38 per cent improvement.
  
  
  CONCLUSIONS
  Patients with an Argus II Retinal Prosthesis implanted for 18 to 44 months (mean 36 months), demonstrated significantly improved completion of vision-related tasks with the device ON versus OFF.
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland, USA.
authors.forename: Duane R
authors.initials: DR
authors.lastname: Geruschat
authors.affiliation: IM3 Inc, Vancouver, Washington, USA. tomami20x@gmail.com.
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Richards
authors.affiliation: Lighthouse Guild International, New York, New York, USA.
authors.forename: Aries
authors.initials: A
authors.lastname: Arditi
authors.affiliation: Moorfields Eye Hospital, London, United Kingdom.
authors.forename: Lyndon
authors.initials: L
authors.lastname: da Cruz
authors.affiliation: Lions Vision Research and Rehab Center, Johns Hopkins University, Baltimore, Maryland, USA.
authors.forename: Gislin
authors.initials: G
authors.lastname: Dagnelie
authors.affiliation: Second Sight Medical Products, Sylmar, California, USA.
authors.forename: Jessy D
authors.initials: JD
authors.lastname: Dorn
authors.affiliation: University of California San Francisco, San Francisco, California, USA.
authors.forename: Jacque L
authors.initials: JL
authors.lastname: Duncan
authors.affiliation: Wills Eye Hospital, Philadelphia, Pennsylvania, USA.
authors.forename: Allen C
authors.initials: AC
authors.lastname: Ho
authors.affiliation: University of Southern California, Los Angeles, California, USA.
authors.forename: Lisa C
authors.initials: LC
authors.lastname: Olmos de Koo
authors.affiliation: Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, France.
authors.forename: José-Alain
authors.initials: JA
authors.lastname: Sahel
authors.affiliation: Manchester Royal Eye Hospital, Manchester, United Kingdom.
authors.forename: Paulo E
authors.initials: PE
authors.lastname: Stanga
authors.affiliation: Hôpitaux Universitaires de Genève, Geneva, Switzerland.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Thumann
authors.affiliation: Retina Foundation of the Southwest, Dallas, Texas, USA.
authors.forename: Vizhong
authors.initials: V
authors.lastname: Wang
authors.affiliation: Second Sight Medical Products, Sylmar, California, USA.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Greenberg
mesh_terms: D006801:Humans; D019919:Prosthesis Implantation; D014785:Vision, Ocular; D057488:Visual Prosthesis
keywords: Argus II; FLORA; functional vision; retinal prosthesis; retinitis pigmentosa