The European project MIVIP has demonstrated the possibility to build a prosthetic device for the transmission of useful visual information to the optic nerve of a blind human suffering from a severe form of retinitis pigmentosa.
A spiral cuff nerve electrode was chronically and intracranially implanted and wrapped around the optic nerve of an RP volunteer. These electrodes induce just enough stress to gently accommodate the nerve swelling succeeding the surgical implant and afterwards nicely come back to fit the smaller diameter once the edema has subsided. Biocompatibility and long term implantation safety have been proven. The electrode selectivity allow for stimulating a limited amount of nerve fibers at specific positions within the nerve trunk as controlled by the stimulation parameters. Very low current give rise to the perception of phosphenes, or visual sensations to be placed in any part of the still fairly broad functional visual field of the patient. Phosphenes can be assembled in recognizable patterns for a person who underwent a suitable training program.
The OPTIVIP project was built on the data gathered from this previous project in order to improve the stimulation strategies and optimize the system components on the basis of more precisely known requirements. Also the surgical procedure was subject to new investigations. These multidisciplinary European collaborative efforts included several implantations in human volunteers with the hope to promote further clinical trials in blind people severely affected by retinitis pigmentosa around the world.
This four year project started on january 1st 2001 and has been completed on October 1, 2005.
GREN's personnel involved in this project included :
Prof. Claude Veraart
Main results of Mivip and Optivip projects are available on this Web site.
This neural sensing project is linked to the F.R.S.M. Grant N° 3.4590.02 project.
Last update: March 22th, 2007.
This website has been designed by the laboratory with the help of Pierre Dubrulle.