title: Visual acuity measurement of prosthetic vision: a virtual-reality simulation study.
abstract: A virtual-reality simulation tested prosthetic visual acuity for both rectangular and hexagonal phosphene grids. Thirteen normally sighted, untrained subjects were required to identify the Landolt C optotype over ten sessions. Overall performance, performance by filter setting (image analysis), and performance by size and orientation of the Landolt C optotype are reported. The results indicated that the hexagonal grid had a slight (4.1%) but statistically significant (p < 0.0001) performance advantage over the rectangular grid for correct identification of the testing symbol. It was also observed that both the phosphene grids had distinct performance profiles relating to their respective spatial orientation. Over the course of the ten sessions, learning afforded subjects an averaged improved performance of 10%.
authors.affiliation: Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
authors.forename: S C
authors.initials: SC
authors.lastname: Chen
authors.forename: L E
authors.initials: LE
authors.lastname: Hallum
authors.forename: N H
authors.initials: NH
authors.lastname: Lovell
authors.forename: G J
authors.initials: GJ
authors.lastname: Suaning
mesh_terms: D001185:Artificial Intelligence; D003198:Computer Simulation; D003199:Computer Systems; D003626:Data Display; D004777:Environment; D019544:Equipment Failure Analysis / Q000379:methods*; D006801:Humans; D009862:Online Systems; D012682:Sensory Aids; D016896:Treatment Outcome; D014584:User-Computer Interface; D014786:Vision Disorders / Q000175:diagnosis* / Q000534:rehabilitation*; D014787:Vision Tests / Q000379:methods*; D014792:Visual Acuity / Q000502:physiology*