Heuristic safety net for transitioning configurations in a neural stimulation system

1. A system for an electrical neurostimulator coupled to a plurality of electrodes, comprising:

telemetry circuitry configured for communicating with the electrical neurostimulator; and

a controller/processor configured for defining an immediate electrode configuration, conveying electrical energy to the plurality of electrodes in accordance with the immediate electrode configuration, defining a final electrode configuration, defining a series of intermediate electrode configurations using a heuristic set of rules based on the immediate electrode configuration and the final electrode configuration, instructing the electrical neurostimulator to convey electrical energy to the plurality of electrodes in accordance with the series of intermediate electrode configurations, and instructing the electrical neurostimulator to convey electrical energy to the plurality of electrodes in accordance with the subsequent electrode configuration;

wherein the heuristic set of rules comprises:

determining whether there exists a first electrode pairing having the cathodic current increase transition and the cathodic current decrease transition, and shifting cathodic current from the electrode having the cathodic current decrease transition to the electrode having the cathodic current increase transition if the first electrode pairing is determined to exist;

determining whether there exists a second electrode pairing having the cathodic current increase transition and the cathodic current decrease/anodic current increase transition, and shifting cathodic current from the electrode having the cathodic current decrease/anodic current increase transition to the electrode having the cathodic current increase transition if the second electrode pairing is determined to exist;

determining whether there exists a third electrode pairing having the anodic current increase transition and the anodic current decrease transition, and shifting anodic current from the electrode having the anodic current decrease transition to the electrode having the anodic current increase transition if the third electrode pairing is determined to exist; and

determining whether there exists a fourth electrode pairing having the anodic current increase transition and the anodic current decrease/cathodic current increase transition, and shifting anodic current from the electrode having the anodic current decrease/cathodic current increase transition to the electrode having the anodic current increase transition if the fourth electrode pairing is determined to exist.

2. The system of claim 1 , wherein the controller/processor is configured for defining the series of intermediate electrode configurations by repeatedly defining a next intermediate electrode configuration based on an immediate previously defined electrode configuration and the final electrode configuration until the next intermediate electrode configuration matches the final electrode configuration.

3. The system of claim 2 , wherein the controller/processor is configured for repeatedly defining the next intermediate electrode configuration by shifting anodic and/or cathodic current from the immediate previously defined electrode configuration to the next intermediate electrode configuration until the intermediate electrode configuration matches the final electrode configuration.

4. The system of claim 3 , wherein the heuristic set of rules comprises limiting shifting of the anodic and/or cathodic current from the immediate previously defined electrode configuration to the next intermediate electrode configuration based on one or more of the following: a maximum change in a cathodic current on an individual one of the electrodes, a maximum change in an anodic current on an individual one of the electrodes, a total maximum change in cathodic current on the electrodes, and a total maximum change in anodic current on the electrodes.

5. The system of claim 3 , wherein each of the electrodes has an electrical current transition between the immediate previously defined electrode configuration and the final electrode configuration that is one of the following: no current change transition, a cathodic current increase transition, a cathodic current decrease transition, a cathodic current decrease/anodic current increase transition, an anodic current increase transition, an anodic current decrease transition, and an anodic current decrease/cathodic current increase transition, and wherein the controller/processor is configured for applying the heuristic set of rules to the electrical current transitions to define the next intermediate electrode configuration.

6. The system of claim 5 , wherein one of the electrodes has the cathodic decrease transition, another one of the electrodes has the cathodic increase transition, and the heuristic set of rules shifts the cathodic current from the one electrode to the other one electrode.

7. The system of claim 5 , wherein one of the electrodes has the cathodic current decrease/anodic current increase transition, and the heuristic set of rules comprises shifting cathodic current from the one electrode to another one of the electrodes.

8. The system of claim 7 , wherein the other one electrode has the cathodic current increase transition.

9. The system of claim 7 , wherein the other one electrode has either the no current change transition or the cathodic current decrease transition.

10. The system of claim 7 , wherein the other one electrode has the cathodic current decrease/anodic current increase transition, and the other one electrode has the greatest cathodic current for the final electrode configuration.

11. The system of claim 5 , wherein one of the electrodes has the anodic decrease transition, another one of the electrodes has the anodic increase transition, and the heuristic set of rules shifts the anodic current from the one electrode to the other one electrode.

12. The system of claim 5 , wherein one of the electrodes has the anodic current decrease/cathodic current increase transition, and the heuristic set of rules shifts the anodic current from the one electrode to another one of the electrodes.

13. The system of claim 12 , wherein the other one electrode has the anodic current increase transition.

14. The system of claim 12 , wherein the other one electrode has either the no current change transition or the anodic current decrease transition.

15. The system of claim 12 , wherein at least one more of the electrodes has the anodic current decrease/cathodic current increase transition, and the one electrode has a greater cathodic current than does the at least one more electrode for the final electrode configuration.

16. The system of claim 5 , wherein the heuristic set of rules further comprises determining whether all of the electrodes either have the cathodic current decrease/anodic current increase transition or the anodic current decrease/cathodic current increase transition.

17. The system of claim 1 , wherein the heuristic set of rules further comprises:

if none of the first, second, third, and fourth electrode pairings exists, determining whether there exists a first electrode having the anodic current decrease/cathodic current increase transition and whether exists a second electrode having either the no current change transition or the anodic current decrease transition; and

if the first and second electrodes exist, shifting anodic current from the first electrode to the second electrode.

18. The system of claim 17 , wherein the heuristic set of rules further comprises, if either the first electrode or the second electrode does not exist, shifting cathodic current from an electrode having the cathodic current decrease/anodic current increase transition to an electrode having either the no current change transition or the cathodic current decrease transition.

19. The system of claim 1 , further comprising a housing containing the telemetry circuitry and the controller/processor.

20. A system for an electrical neurostimulator coupled to a plurality of electrodes, comprising:

telemetry circuitry configured for communicating with the electrical neurostimulator; and

a controller/processor configured for defining an immediate electrode configuration, conveying electrical energy to the plurality of electrodes in accordance with the immediate electrode configuration, defining a final electrode configuration, defining a series of intermediate electrode configurations using a heuristic set of rules based on the immediate electrode configuration and the final electrode configuration, instructing the electrical neurostimulator to convey electrical energy to the plurality of electrodes in accordance with the series of intermediate electrode configurations, and instructing the electrical neurostimulator to convey electrical energy to the plurality of electrodes in accordance with the subsequent electrode configuration, wherein the controller/processor is configured for repeatedly defining the next intermediate electrode configuration by shifting anodic and/or cathodic current from the immediate previously defined electrode configuration to the next intermediate electrode configuration until the intermediate electrode configuration matches the final electrode configuration;

wherein the heuristic set of rules comprises limiting shifting of the anodic and/or cathodic current from the immediate previously defined electrode configuration to the next intermediate electrode configuration based on one or more of the following: a maximum change in a cathodic current on an individual one of the electrodes, a maximum change in an anodic current on an individual one of the electrodes, a total maximum change in cathodic current on the electrodes, and a total maximum change in anodic current on the electrodes;

wherein each of the electrodes has an electrical current transition between the immediate previously defined electrode configuration and the final electrode configuration that is one of the following: no current change transition, a cathodic current increase transition, a cathodic current decrease transition, a cathodic current decrease/anodic current increase transition, an anodic current increase transition, an anodic current decrease transition, and an anodic current decrease/cathodic current increase transition, and wherein the controller/processor is configured for applying the heuristic set of rules to the electrical current transitions to define the next intermediate electrode configuration;

wherein the heuristic set of rules further comprises determining whether all of the electrodes either have the cathodic current decrease/anodic current increase transition or the anodic current decrease/cathodic current increase transition, and if all of the electrodes either have the cathodic current decrease/anodic current increase transition or the anodic current decrease/cathodic current increase transition, determining whether there exists multiple electrodes each having the anodic current decrease/cathodic current increase transition, and if the multiple electrodes exist, determining which one of the multiple electrodes has the greatest cathodic current for the final electrode configuration, and shifting anodic current from the one electrode to another electrode.

21. The system of claim 20 , wherein the heuristic set of rules further comprises, if the multiple electrodes do not exist, determining one electrode having the greatest cathodic current for the previous intermediate electrode configuration, and shifting cathodic current from any electrode having cathodic current for the previous intermediate electrode configuration to the one electrode.

22. A method of providing therapy to a patient using a plurality of electrodes, comprising:

defining an immediate electrode configuration;

conveying electrical energy to the plurality of electrodes in accordance with the immediate electrode configuration;

defining a final electrode configuration;

defining a series of intermediate electrode configurations using a heuristic set of rules based on the immediate electrode configuration and the final electrode configuration;

conveying electrical energy to the plurality of electrodes in accordance with the series of intermediate electrode configurations; and

conveying electrical energy to the plurality of electrodes in accordance with the subsequent electrode configuration;

wherein the heuristic set of rules comprises:

determining whether there exists a first electrode pairing having the cathodic current increase transition and the cathodic current decrease transition, and shifting cathodic current from the electrode having the cathodic current decrease transition to the electrode having the cathodic current increase transition if the first electrode pairing is determined to exist;

determining whether there exists a second electrode pairing having the cathodic current increase transition and the cathodic current decrease/anodic current increase transition, and shifting cathodic current from the electrode having the cathodic current decrease/anodic current increase transition to the electrode having the cathodic current increase transition if the second electrode pairing is determined to exist;

determining whether there exists a third electrode pairing having the anodic current increase transition and the anodic current decrease transition, and shifting anodic current from the electrode having the anodic current decrease transition to the electrode having the anodic current increase transition if the third electrode pairing is determined to exist; and

determining whether there exists a fourth electrode pairing having the anodic current increase transition and the anodic current decrease/cathodic current increase transition, and shifting anodic current from the electrode having the anodic current decrease/cathodic current increase transition to the electrode having the anodic current increase transition if the fourth electrode pairing is determined to exist.

23. The method of claim 22 , wherein defining the series of intermediate electrode configurations comprises repeatedly defining a next intermediate electrode configuration based on an immediate previously defined electrode configuration and the final electrode configuration until the next intermediate electrode configuration matches the final electrode configuration.

24. The method of claim 23 , wherein repeatedly defining the next intermediate electrode configuration comprises shifting anodic and/or cathodic current from the immediate previously defined electrode configuration to the next intermediate electrode configuration until the intermediate electrode configuration matches the final electrode configuration.

25. The method of claim 24 wherein the heuristic set of rules comprises limiting shifting of the anodic and/or cathodic current from the immediate previously defined electrode configuration to the next intermediate electrode configuration based on one or more of the following: a maximum change in a cathodic current on an individual one of the electrodes, a maximum change in an anodic current on an individual one of the electrodes, a total maximum change in cathodic current on the electrodes, a total maximum change in anodic current on the electrodes, and a maximum change in the total current on the electrodes.

26. The method of claim 24 , wherein each of the electrodes has an electrical current transition between the immediate previously defined electrode configuration and the final electrode configuration that is one of the following: no current change transition, a cathodic current increase transition, a cathodic current decrease transition, a cathodic current decrease/anodic current increase transition, an anodic current increase transition, an anodic current decrease transition, and an anodic current decrease/cathodic current increase transition, and wherein the heuristic set of rules are applied to the electrical current transitions to define the next intermediate electrode configuration.

27. The method of claim 26 , wherein one of the electrodes has the cathodic decrease transition, another one of the electrodes has the cathodic increase transition, and the heuristic set of rules shifts the cathodic current from the one electrode to the other one electrode.

28. The method of claim 26 , wherein one of the electrodes has the cathodic current decrease/anodic current increase transition, and wherein the heuristic set of rules comprises shifting cathodic current from the one electrode to another one of the electrodes.

29. The method of claim 28 , wherein the other one electrode has the cathodic current increase transition.

30. The method of claim 28 , wherein the other one electrode has either the no current change transition or the cathodic current decrease transition.

31. The method of claim 28 , wherein the other one electrode has the cathodic current decrease/anodic current increase transition, and the other one electrode has the greatest cathodic current for the final electrode configuration.

32. The method of claim 26 wherein one of the electrodes has the anodic decrease transition, another one of the electrodes has the anodic increase transition, and the heuristic set of rules shifts the anodic current from the one electrode to the other one electrode.

33. The method of claim 24 , wherein one of the electrodes has the anodic current decrease/cathodic current increase transition, and wherein the heuristic set of rules shifts the anodic current from the one electrode to another one of the electrodes.

34. The method of claim 33 , wherein the other one electrode has the anodic current increase transition.

35. The method of claim 33 , wherein the other one electrode has either the no current change transition or the anodic current decrease transition.

36. The method of claim 33 , wherein at least one more of the electrodes has the anodic current decrease/cathodic current increase transition, and the one electrode has a greater cathodic current than does the at least one more electrode for the final electrode configuration.

37. The method of claim 22 , wherein the heuristic set of rules further comprises:

if none of the first, second, third, and fourth electrode pairings exists, determining whether there exists a first electrode having the anodic current decrease/cathodic current increase transition and whether exists a second electrode having either the no current change transition or the anodic current decrease transition; and

if the first and second electrodes exist, shifting anodic current from the first electrode to the second electrode.

38. The method of claim 37 , wherein the heuristic set of rules further comprises, if either the first electrode or the second electrode does not exist, shifting cathodic current from an electrode having the cathodic current decrease/anodic current increase transition to an electrode having either the no current change transition or the cathodic current decrease transition.

39. The method of claim 24 , wherein the heuristic set of rules further comprises determining whether all of the electrodes either have the cathodic current decrease/anodic current increase transition or the anodic current decrease/cathodic current increase transition.

40. A method of providing therapy to a patient using a plurality of electrodes, comprising:

defining an immediate electrode configuration;

conveying electrical energy to the plurality of electrodes in accordance with the immediate electrode configuration;

defining a final electrode configuration;

defining a series of intermediate electrode configurations using a heuristic set of rules based on the immediate electrode configuration and the final electrode configuration;

conveying electrical energy to the plurality of electrodes in accordance with the series of intermediate electrode configurations; and

conveying electrical energy to the plurality of electrodes in accordance with the subsequent electrode configuration;

wherein defining the series of intermediate electrode configurations comprises repeatedly defining a next intermediate electrode configuration based on an immediate previously defined electrode configuration and the final electrode configuration until the next intermediate electrode configuration matches the final electrode configuration;

wherein repeatedly defining the next intermediate electrode configuration comprises shifting anodic and/or cathodic current from the immediate previously defined electrode configuration to the next intermediate electrode configuration until the intermediate electrode configuration matches the final electrode configuration;

wherein the heuristic set of rules further comprises determining whether all of the electrodes either have the cathodic current decrease/anodic current increase transition or the anodic current decrease/cathodic current increase transition, and if all of the electrodes either have the cathodic current decrease/anodic current increase transition or the anodic current decrease/cathodic current increase transition determining whether there exists multiple electrodes each having the anodic current decrease/cathodic current increase transition, and if the multiple electrodes exist, determining which one of the multiple electrodes has the greatest cathodic current for the final electrode configuration, and shifting anodic current from the one electrode to another electrode.

41. The method of claim 40 , wherein the heuristic set of rules further comprises, if the multiple electrodes do not exist, determining one electrode having the greatest cathodic current for the previous intermediate electrode configuration, and shifting cathodic current from any electrode having cathodic current for the previous intermediate electrode configuration to the one electrode.