Photovoltaic restoration of sight with high visual acuity

Nat Med. 2015 May;21(5):476-82. doi: 10.1038/nm.3851. Epub 2015 Apr 27.


Patients with retinal degeneration lose sight due to the gradual demise of photoreceptors. Electrical stimulation of surviving retinal neurons provides an alternative route for the delivery of visual information. We demonstrate that subretinal implants with 70-μm-wide photovoltaic pixels provide highly localized stimulation of retinal neurons in rats. The electrical receptive fields recorded in retinal ganglion cells were similar in size to the natural visual receptive fields. Similarly to normal vision, the retinal response to prosthetic stimulation exhibited flicker fusion at high frequencies, adaptation to static images and nonlinear spatial summation. In rats with retinal degeneration, these photovoltaic arrays elicited retinal responses with a spatial resolution of 64 ± 11 μm, corresponding to half of the normal visual acuity in healthy rats. The ease of implantation of these wireless and modular arrays, combined with their high resolution, opens the door to the functional restoration of sight in patients blinded by retinal degeneration.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Angiography
  • Animals
  • Electric Stimulation
  • Electrophysiological Phenomena
  • Female
  • Fluorescein / chemistry
  • Lasers
  • Male
  • Neurons / metabolism
  • Neurons / physiology*
  • Photochemistry / methods*
  • Prostheses and Implants
  • Rats
  • Retina / metabolism
  • Retinal Degeneration / therapy*
  • Retinal Ganglion Cells / cytology*
  • Retinal Neurons / metabolism
  • Spectrophotometry, Infrared
  • Vision, Ocular / physiology*
  • Visual Acuity / physiology*


  • Fluorescein