System and method for nerve modulation using noncontacting electrodes
An implant unit configured for implantation into a body of a subject may include an antenna configured to receive a signal. The implant unit may also include at least one pair of modulation electrodes configured to be implanted into the body of the subject in the vicinity of at least one nerve to be modulated, the at least one pair of modulation electrodes being configured to receive an applied electric signal in response to the signal received by the antenna and generate an electrical field to modulate the at least one nerve from a position where the at least one pair of modulation electrodes does not contact the at least one nerve.
1. An implant unit configured for implantation into a body of a subject, comprising:
an antenna configured to receive a signal;
at least one pair of modulation electrodes configured to be implanted into the body of the subject in the vicinity of at least one nerve to be modulated, the at least one pair of modulation electrodes being configured to receive an applied electric signal in response to the signal received by the antenna and generate an electrical field to modulate the at least one nerve from a position where the at least one pair of modulation electrodes are spaced apart from the at least one nerve;
a non-linear circuit including a harmonics modifier circuit configured to modify at least the even-th order harmonics in an oscillatory behavior of the non-linear circuit; and
a processor configured to determine a coupling between the antenna and another antenna external to the implant unit based on the non-linear behavior of the non-linear circuit.
2. The implant unit of claim 1 , wherein the electric field generated by the at least one pair of modulation electrodes is configured to penetrate tissue between the at least one pair of modulation electrodes and the at least one nerve in order to induce modulation of the at least one nerve.
3. The implant unit of claim 2 , wherein the tissue includes one or more of a muscle, bone, connective tissue, or adipose tissue.
4. The implant unit of claim 1 , wherein the at least one pair of modulation electrodes is configured such that the generated electric field provides an energy density sufficient to modulate the at least one nerve without contacting the at least one nerve.
5. The implant unit of claim 1 , wherein the electric signal received by the at least one pair of modulation electrodes includes a voltage of between about 0.5 volts and about 40 volts.
6. The implant unit of claim 1 , wherein the electric signal received by the at least one pair of modulation electrodes includes a current of between about 50 microamps and about 20 milliamps.
7. The implant unit of claim 1 , wherein each of the electrodes of the at least one pair of modulation electrodes includes a surface area of about 0.01 mm 2 to about 80 mm 2 .
8. The implant unit of claim 1 , wherein the electrodes of the at least one pair of modulation electrodes are separated from one another by a distance of less than about 25 mm.
9. The implant unit of claim 1 , further including a flexible carrier associated with at least one of the antenna and the at least one pair of electrodes, wherein the flexible carrier includes a biocompatible polymer including at least one of silicone, phenyltrimethoxysilane (PTMS), polymethyl methacrylate (PMMA), parylene C, polyimide, liquid polyimide, laminated polyimide, black epoxy, polyether ether ketone (PEEK), liquid crystal polymer (LCP), Kapton, or combinations thereof.
10. The implant unit of claim 1 , wherein the at least one pair of modulation electrodes includes line electrodes, point electrodes, or combinations thereof.
11. The implant unit of claim 1 , wherein each of the at least one pair of modulation electrodes includes an anode and a cathode spaced apart from one another by a distance of from about 0.2 mm to about 25 mm.
12. The implant unit of claim 1 , wherein the at least one pair of modulation electrodes includes a first pair of electrodes provided on a first side of the implant unit and a second pair of electrodes provided on a second side of the implant unit different from the first side.
13. The implant unit of claim 12 , wherein the first pair of electrodes and the second pair of electrodes can be activated to simultaneously generate respective electric fields.
14. The implant unit of claim 12 , wherein the first pair of electrodes and the second pair of electrodes can be activated to sequentially generate respective electric fields.
15. The implant unit of claim 1 , wherein the implant unit is configured to receive an alternating current (AC) signal via the antenna and cause application of at least one of a direct current (DC) signal and an AC signal to the at least one pair of electrodes in response to the AC signal.