METHOD, SYSTEM AND APPARATUS FOR AUTOMATED TERMINATION OF A THERAPY FOR AN EPILEPTIC EVENT UPON A DETERMINATION OF EFFECTS OF A THERAPY

• US 20120046711A1
• Filed: 10/24/2011
• Published: 02/23/2012
• Est. Priority Date: 03/23/2009
• Status: Active Grant

• Current Assignee: Flint Hills Scientific, LLC
• Original Assignee: Flint Hills Scientific, LLC
• Inventors: Osorio, Ivan
• Granted Patent: US 9,533,147 B2
• Time in Patent Office: Days
• US Class Current: 607/45
• CPC Class Codes: A61B 5/4094 Diagnosing or monitoring seizure diseases, e.g. epilepsy
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61B 5/4848 Monitoring or testing the effects of treatment, e.g. of medication
• CPC Class Codes: A61F 7/12 Devices for heating or cooling internal body cavities
• CPC Class Codes: A61N 1/0529 Electrodes for brain stimulation
• CPC Class Codes: A61N 1/36064 Epilepsy
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362
• CPC Class Codes: A61N 1/36139 with automatic adjustment
• CPC Class Codes: A61N 1/36142 for improving safety
• CPC Class Codes: A61N 1/36146 specified by the stimulation parameters
• CPC Class Codes: A61N 1/3621 for treating or preventing abnormally high heart rate
• CPC Class Codes: A61N 2/002 in combination with another treatment
• CPC Class Codes: A61N 2/006 for magnetic stimulation of nerve tissue
• CPC Class Codes: A61N 5/0622 Optical stimulation for exciting neural tissue

Abstract

A method comprising detecting an epileptic event in a patient; applying an electrical therapy to a first target area in at least one of a brain region or a cranial nerve of said patient in response to said detecting; receiving a body signal responsive to the electrical therapy, wherein said body signal is selected from an autonomic signal, a neurologic signal, a metabolic signal, an endocrine signal, or a tissue stress marker signal; determining whether said body signal indicates that said electrical therapy has an efficacious effect; and terminating the application of said electrical therapy if the response indicates that the electrical therapy has an efficacious effect. An apparatus capable of performing the method. A non-transitive, computer-readable storage device for storing data that when executed by a processor, perform the method.

Claims

1. A method, comprising:

detecting an epileptic event in a patient based on at least one detection body signal selected from at least one of an autonomic signal, a neurologic signal, a metabolic signal, an endocrine signal, and a tissue stress marker signal;

applying an electrical therapy to a first target tissue in at least one of a brain region or a cranial nerve of said patient in response to said detecting the event;

receiving an efficacy body signal after applying the electrical therapy, wherein said efficacy body signal is selected from at least one of an autonomic signal, a neurologic signal, a metabolic signal, an endocrine signal, and a tissue stress marker signal;

determining whether said efficacy body signal indicates that said electrical therapy has an efficacious effect; and

terminating the application of said electrical therapy if the determining indicates that the electrical therapy has an efficacious effect.

2. The method of claim 1, wherein detecting an epileptic event is based on at least one body signal selected from a cardiac signal, a kinetic signal, or a responsiveness signal.

3. The method of claim 1, wherein said detecting is based upon at least one of a cardiac index determined from said cardiac signal, a kinetic index determined from said kinetic signal, or a responsiveness index determined from said responsiveness signal;

and wherein said efficacious effect is at least one of a return of a cardiac index towards an interictal baseline, a change in a kinetic index towards an interictal baseline, a return of a responsiveness index towards an interictal baseline, or termination of said epileptic event.

4. The method of claim 1 further comprising continuing the application of said electrical therapy if said determining does not indicate that said electrical therapy has an efficacious effect.

5. The method of claim 4 wherein continuing said therapy comprises resuming said therapy for a predetermined duration.

6. The method of claim 1 further comprising terminating the application of said electrical therapy based on a safety duration constraint if the determining does not indicate that said electrical therapy has an efficacious effect.

7. The method of claim 1 further comprising

determining whether said efficacy body signal indicates that said electrical therapy has an adverse effect;

and

terminating the application of said electrical therapy if the response indicates that the electrical therapy has an adverse effect.

8. The method of claim 7 wherein determining whether said efficacy body signal indicates that said electrical therapy has an adverse effect comprises:

determining an adverse effect index and

comparing said adverse effect index to an adverse effect threshold.

9. The method of claim 8, further comprising:

modifying at least one parameter of said electrical therapy if

a) said efficacy body signal is indicative of lack of an efficacious effect,

b) said adverse event index reaches an adverse event threshold;

,

c) said efficacy body signal is indicative of an unsafe effect;

or

d) said electrical therapy is not tolerated by the patient; and

delivering the modified electrical therapy to at least one of said brain region or said cranial nerve of said patient.

10. The method of claim 1 further comprising:

applying an electrical therapy to a second target tissue in at least one of a brain region or a cranial nerve of the patient if the determining is not indicative of an efficacious effect.

11. The method of claim 1 wherein

receiving an efficacy body signal after applying the electrical therapy comprises receiving at least a first and a second efficacy body signal, wherein said first and second efficacy body signals are selected from an autonomic signal, a neurologic signal, a metabolic signal, an endocrine signal, and a tissue stress marker signal;

determining whether said efficacy body signal indicates that said electrical therapy has an efficacious effect comprises determining whether each of said first and said second efficacy body signals indicates that said electrical signal therapy has an efficacious effect; and

terminating the application of said electrical therapy comprises terminating said therapy only if both said first and said second efficacy body signals indicate that the electrical therapy has an efficacious effect.

12. The method of claim 9, wherein modifying said at least one parameter comprises modifying a parameter selected from the group consisting of a waveform, a pulse width, a total number of pulses, a number of pulses per unit time, a frequency of pulses per unit time, an inter-pulse interval, an amplitude, a phase, number of phases in a pulse, a number of phases in a pulse train, a polarity of pulse phase, a current density per pulse, a total current density for a pulse train, a degree of isotropy of current flow, a time delay between the delivery of a current and its arrival at a body target, a timing of therapy delivery relative to a zero-crossing of the efficacy body signal, a timing of the therapy delivery relative to an extrema occurrence of the efficacy body signal, or a timing of the therapy delivery relative to a region of an ascending or descending slope of a body signal oscillation.

13. The method of claim 1 wherein determining whether said electrical therapy has an efficacious effect comprises:

determining an efficacy index based upon said efficacy body signal; and

continuing said therapy in response to determining that the efficacy index is below an efficacy threshold;

and wherein terminating the application of the electrical therapy comprises terminating the therapy if the efficacy index equals or exceeds the efficacy threshold.

14. The method of claim 1 wherein determining whether said efficacy body signal indicates that said electrical therapy has an efficacious effect comprises consideration of at least one of time of day, level of consciousness, level of cognitive activity, level of physical activity, time from previous seizure, seizure severity, time to recover from post-ictal period, seizure history, seizure adverse events, or quality of life.

15. The method of claim 1 wherein:

said electrical therapy comprises at least one electrical pulse;

said determining of whether said at least one electrical pulse has an efficacious effect comprises determining a change in at least one of an amplitude variance of the efficacy body signal, an extrema variance of the efficacy body signal, a zero-crossing variance of the efficacy body signal, or a slope variance of the body signal, said change being temporally correlated with applying the at least one electrical pulse; and

terminating the application of the at least one electrical pulse comprises not delivering another pulse in response to determining that the electrical therapy has an efficacious effect.

16. The method of claim 1, wherein said electrical therapy comprises an electrical pulse having a programmed pulse width, and terminating the application of the electrical therapy comprises terminating delivery of the electrical pulse prior to the end of the programmed pulse width.

17. The method of claim 1, wherein said electrical therapy comprises applying electrical pulses to a target portion of a vagus nerve for a programmed duration, and wherein terminating the application of the electrical therapy comprises terminating delivery of the electrical pulses prior to the end of the programmed duration.

18. The method of claim 1, wherein said determining whether said efficacy body signal indicates that said electrical therapy has an efficacious effect occurs at a time selected from

continuously after applying the electrical therapy, and

discretely after applying the electrical therapy for a predetermined duration.

19. The method of claim 1 wherein detecting an epileptic event comprises detecting a first epileptic seizure onset, and wherein terminating comprises interrupting the application of said electrical therapy when the response indicates that the electrical therapy has an efficacious effect, said method further comprising

detecting an end of the seizure, and

not resuming applying said electrical therapy after said terminating until the occurrence of an event selected from

a relapsing of the first epileptic seizure,

an end of the first epileptic seizure,

the elapse of a re-initiation time period after the termination of the therapy,

an onset of a second epileptic seizure,

receiving an indication that a cumulative seizure severity index has been reached,

receiving an indication that a cumulative seizure frequency index has been reached,

receiving an indication that resumption of said electrical therapy does not exceed a predetermined stimulation maximum,

an indication that application of the electrical therapy will not result in an adverse effect, or

receiving an indication of the lapse of a beneficial carryover effect.

20. The method of claim 19 wherein detecting said epileptic seizure comprises at least one of a cardiac index exceeding a cardiac index threshold and a body movement index exceeding a body movement index threshold, and wherein detecting an end of the first epileptic seizure comprises at least one of said cardiac index crossing a cardiac ictal-to-postictal index threshold and said body movement index crossing a body movement ictal-to-postictal threshold.

21. A medical device system, comprising:

an epileptic seizure detection module configured to detect a first epileptic seizure based on at least one of a cardiac index and a kinetic index;

a therapy module configured to apply a therapy to at least one neural structure of said patient based on an indication of said epileptic seizure;

at least one sensor configured to collect one or more body signals from a patient'"'"'s body;

an efficacy determination module configured to receive said collected one or more body signals and detect a response of said epileptic event to said therapy, wherein said detection is based on said collected one or more body signals; and

a therapy termination module configured to terminate said therapy based on an indication that said therapy has an efficacious effect, and to prohibit the application of the therapy until the occurrence of an event selected from a worsening of the first epileptic seizure, a relapsing of the first epileptic seizure, an end of the first epileptic seizure, the elapse of a re-initiation time period after the termination of the therapy, an onset of a second epileptic seizure, receiving an indication that a cumulative seizure severity index has been reached, receiving an indication that a cumulative seizure frequency index has been reached, receiving an indication that resumption of said electrical therapy does not exceed a predetermined stimulation limit, an indication that application of the electrical therapy will not result in an adverse effect, and receiving an indication of the lapse of a beneficial carryover effect.

22. The medical device system of claim 21, further comprising an adverse effect determination module configured to receive said one or more body signals and detect an adverse effect of said therapy based on the one or more body signals.

23. The medical device system of claim 21, wherein the re-initiation time period is one of:

a programmed time having a fixed duration;

a time period determined based upon the one or more body signals received by the efficacy determination module;

a time period dependent upon one of a time of day, a time of month, whether the patient is asleep or awake, an attention level, a physical activity level, and whether the patient is recumbent or standing,

a time elapsed from a previous seizure,

a time period depending upon one of a severity of a previous seizure, a seizure history over at least one time scale;

a time since a last therapy;

a time depending upon a type of therapy, stimulation parameters, and the patient'"'"'s planned activity.

24. The medical device system of claim 21, further comprising:

a therapy modification module configured to modify at least one parameter of said therapy, based on an indication said response is not indicative of an efficacious effect or is indicative of an adverse effect; and

wherein said therapy module is configured to apply said modified therapy to at least one neural structure of said patient or to terminate therapy.

25. The medical device system of claim 24, wherein said therapy is an electrical therapy, and modifying said at least one parameter comprises modifying a parameter selected from the group consisting of a waveform, a pulse width, a total number of pulses, a number of pulses per unit time, a frequency of pulses per unit time, an inter-pulse interval, an amplitude, a phase, number of phases in a pulse, a number of phases in a pulse train, a polarity of pulse phase, a current density per pulse, a total current density for a pulse train, a degree of isotropy of current flow, a time delay between the delivery of a current and its arrival at a body target, a timing of therapy delivery relative to a zero-crossing of the efficacy body signal, a timing of the therapy delivery relative to an extremum occurrence of the efficacy body signal, or a timing of the therapy delivery relative to a region of an ascending or descending slope of a body signal.