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Updated: Jul 17, 2026
06:49
Visual Evoked Potential Recording in a Rat Model of Experimental Optic Nerve Demyelination
Published on: July 29, 2015
Vision rehabilitation with the optic nerve visual prosthesis.
1Neural Rehabilitation Engineering Laboratory, Universite Catholique de Louvain, Brussels, Belgium.
Summary
A novel optic nerve visual prosthesis successfully activated retinal ganglion cell axons in a blind volunteer. This technology can evoke visual phosphenes and aid in object localization and discrimination.
Area of Science:
- Ophthalmology
- Neuroscience
- Biomedical Engineering
Background:
- Retinitis pigmentosa causes progressive vision loss.
- Visual prostheses aim to restore sight by bypassing damaged retinal cells.
- Optic nerve stimulation offers a potential pathway for visual information delivery.
Purpose of the Study:
- To evaluate the safety and efficacy of a chronically implanted optic nerve visual prosthesis.
- To assess the ability of electrical stimulation to evoke visual percepts (phosphenes).
- To determine if the prosthesis can provide useful visual information for object perception.
Main Methods:
- Chronic implantation of an optic nerve visual prosthesis in a volunteer with retinitis pigmentosa.
- Controlled electrical stimulation of the optic nerve.
- Subjective reporting of elicited sensations (phosphenes) and visual experiences.
Main Results:
- Successful activation of retinal ganglion cell axons.
- Evocation of distinct phosphenes across a wide visual field.
- No non-visual sensations were reported.
- Demonstrated ability to convey visual information for object localization and discrimination.
Conclusions:
- Chronic optic nerve stimulation is feasible for visual prosthesis application.
- The visual prosthesis effectively transmitted visual information.
- This technology shows promise for restoring functional vision in individuals with retinitis pigmentosa.
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