Visual Prosthesis

• US 20080262569A1
• Filed: 10/19/2007
• Published: 10/23/2008
• Est. Priority Date: 10/20/2006
• Status: Active Grant

• Current Assignee: Doheny Eye Institute, Second Sight Medical Products, Inc.
• Original Assignee: Doheny Eye Institute
• Inventors: Greenberg, Robert J., McClure, Kelly H., McMahon, Matthew J., Humayun, Mark S.
• Granted Patent: US 8,239,033 B2
• Time in Patent Office: Days
• US Class Current: 607/54
• CPC Class Codes: A61N 1/36046 of the eye
• CPC Class Codes: A61N 1/37247 User interfaces, e.g. input or presentation means

Abstract

A method for stimulating a subject'"'"'s retina. The method comprising selecting at least a first and a second electrode each configured to apply current to a subject'"'"'s retina, determining impedance for the at least first electrode and second electrode, and applying current to the subject'"'"'s retina through the at least first and second electrode, wherein current to be applied by the first electrode and the second electrode is configured to be higher for the first electrode when the first electrode has an impedance lower than a second electrode'"'"'s impedance.

Claims

1. A method for stimulating a subject'"'"'s retina, the method comprising:

selecting at least a first and a second electrode each configured to apply current to a subject'"'"'s retina;

determining impedance for the at least first electrode and second electrode; and

applying current to the subject'"'"'s retina through the at least first and second electrode, wherein current to be applied by the first electrode and the second electrode is configured to be higher for the first electrode when the first electrode has an impedance lower than a second electrode'"'"'s impedance.

2. The method of claim 1, wherein the at least first and second electrode are part of an array of electrodes.

3. The method of claim 2, wherein the array of electrodes is an array of 6×

10 electrodes.

4. The method of claim 1, wherein determining impedance for the at least first electrode and second electrode comprises:

applying current through the first electrode and second electrode;

determining voltage drop across the first electrode and second electrode; and

calculating impedance of the first electrode and second electrode based on the voltage drop across the first electrode and second electrode.

5. The method of claim 4, wherein the current being applied to the electrodes when determining impedance of the electrodes is below a threshold current required to create perception of light by the subject.

6. The method of claim 1, wherein determining impedance of the electrodes is performed continuously or manually.

7. A method for implanting electrodes in a subject'"'"'s retina, the method comprising:

a) temporarily placing electrodes in a subject'"'"'s retina;

b) determining impedance of the placed electrodes; and

c) repeating features a) and b) until impedance of the electrodes is ideal for permanent implanting of the electrodes.

8. The method of claim 7, wherein the electrodes are part of an array of electrodes.

9. The method of claim 8, wherein the array of electrodes is an array of 6×

10 electrodes.

10. The method of claim 7, wherein determining impedance of the electrodes comprises:

applying current through the electrodes;

determining voltage drop across each of the electrodes; and

calculating impedance of each electrode based on the voltage drop across each electrode.

11. The method of claim 10, wherein the current applied to the electrodes when determining the impedance of the electrodes is below a threshold current required to create perception of light by the subject.

12. A method for applying current to a load, the method comprising:

selecting a first and a second electrode each configured to apply current to a load;

determining impedance of the electrodes; and

applying current to the load through the first and second electrode, wherein current to be applied by the first electrode and the second electrode is configured to be higher for the first electrode when the first electrode has an impedance lower than a second electrode'"'"'s impedance.

13. The method of claim 12, wherein the at least first and second electrode are part of an array of electrodes.

14. The method of claim 13, wherein the array of electrodes is an array of 6×

10 electrodes.

15. The method of claim 12, wherein the load is a retina.

16. A method for stimulating a subject'"'"'s retina, the method comprising:

selecting at least a first and a second electrode, each configured to apply current to a subject'"'"'s retina; and

applying current to the subject'"'"'s retina through the first and second electrode, wherein current to be applied by the first electrode and the second electrode is configured to be higher for the first electrode when the first electrode is disposed farther from the subject'"'"'s retina than the second electrode.

17. The method of claim 16, wherein the at least first and second electrode are part of an array of electrodes.

18. The method of claim 17, wherein the array of electrodes is an array of 6×

10 electrodes.

19. A method for determining which electrode is to be in contact with a subject'"'"'s retina, the method comprising:

applying current to a plurality of electrodes implanted in the subject'"'"'s eye;

determining impedance of each electrode of the plurality of electrodes; and

establishing the electrode with the highest impedance as the electrode in contact with the subject'"'"'s retina.

20. The method of claim 19, wherein the plurality electrode are part of an array of electrodes.

21. The method of claim 20, wherein the array of electrodes is an array of 6×

10 electrodes.

22. The method of claim 19, wherein determining impedance of each electrode comprises:

determining voltage drop across each of the electrodes; and

calculating impedance of each electrode based on the voltage drop across each electrode.

23. The method of claim 19, wherein the current being applied to the electrodes is below a threshold current required to create perception of light by the subject.