Cortical visual prosthesis
The present invention is a visual prosthesis adapted for implantation in the brain, and more particularly with an electrode array adapted for implantation in the Calcarine Sulcus of the visual cortex. The electrode array of the invention has electrodes on each side and spaced appropriately for the Calcarine Sulcus and driven by an electronic circuit within a hermetic package small enough to be implanted with a skull.
1. A visual prosthesis comprising:
a flexible circuit and including a bond pad portion, and cable portion and an electrode array portion including stimulating electrodes including a platinum grey surface coating on a first side of the flexible circuit and stimulating electrodes including a platinum grey surface coating on a second side opposite the first side, offset from the electrodes on the first side and, adapted to stimulate neurons in the brain;
a driver circuit driving stimulation signals on the flexible circuit, the driver circuit within a hermetic housing suitable to be implanted with a head; and
a coil providing power and data to the driver circuit.
2. The visual prosthesis according to claim 1 , wherein flexible circuit includes more than one branch suitable to stimulate different regions.
3. The visual prosthesis according to claim 2 , wherein the flexible circuit includes four or more branches.
4. The visual prosthesis according to claim 1 , wherein the electrodes are organized on the flexible circuit in a rectangular pattern.
5. The visual prosthesis according to claim 1 , wherein the electrodes are organized on the flexible circuit in a hexagonal pattern.
6. The visual prosthesis according to claim 1 , wherein the electrodes are organized in the flexible circuit having varying pitch.
7. The visual prosthesis according to claim 6 , wherein the varying pitch is closer toward the fovea of the Calcarine Sulcus.
8. The visual prosthesis according to claim 1 , wherein the electrode array portion is between 2 to 6 mm by 10 to 20 mm.
9. The visual prosthesis according to claim 1 , wherein the electrode array portion is about 4 by 15 mm.
10. The visual prosthesis according to claim 1 , wherein the flexible circuit is constructed of polyimide dielectric films encapsulating platinum conductive traces.
11. The visual prosthesis according to claim 1 , wherein the flexible circuit includes soft polymer bumpers around at least a portion of its edges.
12. The visual prosthesis according to claim 11 , wherein the soft polymer is silicone.
13. The visual prosthesis according to claim 1 , wherein the driver circuit or coil includes a magnet suitable to locate an external coil in proper relation to the coil.
14. The visual prosthesis according to claim 1 , wherein the electrodes are arranged in a pattern with a width length greater than a width and the cable portion attaching to the electrode array portion at its length.
15. The visual prosthesis according to claim 1 , wherein the electrodes are arranged in a pattern with a width length greater than a width and the cable portion attaching to the electrode array portion at its width.
16. The visual prosthesis according to claim 1 , wherein the electrodes are arranged in a pattern with a width length greater than a width and the cable portion attaching to the electrode array portion at a corner between its length and width.