Spatial Resolution and Perception of Patterns Mediated by a Subretinal 16-Electrode Array in Patients Blinded by Hereditary Retinal Dystrophies

PURPOSE. The perception of 11 persons blinded by hereditary retinal degeneration elicited by a subretinally implanted 16- electrode array used for light-independent direct stimulation of the retina is described. This device is part of the Tubingen retina implant, which also employs a light-sensitive, multipho- todiode array (MPDA). The ability to reliably recognize com- plex spatial percepts was investigated. METHODS. Eleven blind volunteers received implants and par- ticipated in standardized psychophysical tests investigating the size and shape of perceptions elicited by single-electrode acti- vation, multiple-electrode activation, and activation of com- pound patterns such as simplified letters.