Method and apparatus for electronically switching electrode configuration
A method and apparatus for selecting neural stimulation electrode configuration is provided. One aspect of this disclosure relates to an implantable medical device including a neural stimulator adapted to generate neural stimulation signals and an electrode configuration tester for testing a first electrode configuration for stimulating a desired neural target. The device includes a controller to control the neural stimulator to selectively provide a first neural stimulation signal with appropriate signal characteristics to stimulate the desired neural target using the first electrical configuration and a second neural stimulation signal with appropriate signal characteristics to stimulate the desired neural target using a second electrode configuration, and adapted to communicate with the electrode configuration tester and to respond to an indication that an efficacy of the first electrode configuration is lower than a threshold by providing the neural stimulation using the second neural stimulation signal. Other aspects and embodiments are provided herein.
1. An implantable medical device, comprising:
a neural stimulator adapted to provide neural stimulation therapy using either a first electrode configuration to deliver neural stimulation or a second electrode configuration to deliver neural stimulation;
a controller operably connected to the neural stimulator and configured to select the first electrode configuration to control delivery of the neural stimulation therapy through the first electrode configuration;
an electrode configuration tester for testing for a fault in the first electrode configuration during delivery of the neural stimulation therapy to a patient, the fault occurring when the efficacy of the neural stimulation therapy using the first electrode configuration is lower than a threshold; and
the controller operably connected to the electrode configuration tester to repeatedly test the first electrode configuration during delivery of the neural stimulation therapy to ensure uninterrupted neural stimulation to the patient, and to respond to a detected failure in the first electrode configuration by selecting the second electrode configuration and controlling delivery of the neural stimulation therapy through the second electrode configuration.
2. The implantable medical device of claim 1 , wherein the first and second stimulation signals have same signal characteristics.
3. The implantable medical device of claim 1 , wherein the first and second stimulation signals have different signal characteristics.
4. The implantable medical device of claim 1 , wherein the first electrode configuration is unipolar.
5. The implantable medical device of claim 1 , wherein the first electrode configuration is bipolar.
6. The implantable medical device of claim 1 , wherein the first electrode configuration is multipolar.
7. The implantable medical device of claim 1 , wherein the first electrode configuration includes an intravascular electrode to transvascularly stimulate the neural target.
8. The implantable medical device of claim 1 , wherein the first electrode configuration includes a nerve cuff electrode.
9. The implantable medical device of claim 1 , wherein the electrode configuration tester includes an impedance measurement circuit to measure impedance for the first electrode configuration, compare the measured impedance to a desired impedance range for the first electrode configuration, and determine that the efficacy of the first electrode configuration is below a threshold when the measured impedance is not within the desired range.
10. The implantable medical device of claim 1 , wherein the electrode configuration tester is adapted to measure physiological response for the first electrode configuration, compare the measured physiological response to a desired range for the physiological response, and determine that the efficacy of the first electrode configuration is below a threshold when the measured physiological response is not within the desired range.
11. The implantable medical device of claim 1 , further comprising:
at least one neural stimulation lead having a proximal portion and a distal portion;
a plurality of electrodes along the distal portion of the at least one lead, with at least one of the plurality of electrodes forming part of the first electrode configuration to deliver neural stimulation therapy and another at least one of the plurality of electrodes forming part of the second electrode configuration to deliver neural stimulation therapy; and
wherein a portion of the implantable medical device is coup led to the proximal portion of the at least one lead.
12. The implantable medical device of claim 11 , further comprising:
a telemetry circuit to communicate with the controller and an external module.
13. The implantable medical device of claim 11 , further comprising:
a memory circuit to communicate with the controller; and
computer-readable instructions embedded in the memory circuit, the computer-readable instructions being operable on by the controller to control delivery of neural stimulation therapy.
14. The implantable medical device of claim 13 , wherein the at least one neural stimulation lead includes a nerve cuff.
15. The implantable medical device of claim 13 , wherein the memory circuit is adapted to store measured impedance at different times for a time period to enable trending of the measured impedance.
16. The implantable medical device of claim 11 , wherein the at least one neural stimulation lead includes a direct stimulation lead for providing stimulation directly to a nerve trunk.
17. The implantable medical device of claim 11 , wherein the at least one neural stimulation lead includes an indirect stimulation lead for providing stimulation indirectly to a nerve trunk, through the wall of an adjacent blood vessel.
18. The implantable medical device of claim 11 , further comprising a second lead having at least one additional electrode configuration.
19. The implantable medical device of claim 11 , wherein the controller is configured to measure impedance for the first electrode configuration periodically.
20. The implantable medical device of claim 11 , wherein the controller is configured to measure the impedance for the first electrode configuration in between deliveries of neural stimulation therapy.