Apparatuses and methods for setting an electrical dose
Methods and apparatuses for setting a therapeutic dose of a neuromodulator implanted into a patient are described. The therapeutic dose typically includes a therapeutic dose duration including a ramp-up time to reach a peak modulation voltage and a sustained peak modulation time during which the voltage is sustained at the peak modulation voltage. The methods and apparatuses described herein may use a testing ramp to identify a peak modulation voltage that is patient-specific and provides a maximized therapeutic effect while remaining comfortably tolerable by the patient during the application of energy by the neuromodulator.
1. A method of setting a therapeutic dose of a neuromodulator implanted into a patient, wherein the therapeutic dose comprises a therapeutic dose duration including a therapy ramp-up time to reach a peak modulation voltage and a sustained peak modulation time during which a voltage is sustained at the peak modulation voltage, the method comprising:
applying a test voltage ramp from the neuromodulator implanted into the patient;
determining a target sensation intensity modulation voltage that is specific to the patient from the test voltage ramp, wherein the target sensation intensity modulation voltage is a maximum voltage that the patient can tolerate during application of the test voltage ramp;
calculating an estimated peak modulation voltage as a square root of a product of the therapy ramp-up time and the target sensation intensity modulation voltage, wherein the therapy ramp-up time is a set percentage of the therapeutic dose duration; and
setting the therapeutic dose using the estimated peak modulation voltage.
2. The method of claim 1 , wherein the target sensation intensity modulation voltage is a maximum patient-tolerable modulation voltage.
3. The method of claim 1 , wherein the therapy ramp-up time to the peak modulation voltage is set to be half of the therapeutic dose duration.
4. The method of claim 1 , wherein the therapeutic dose duration is set to be 30 minutes.
5. The method of claim 1 , wherein determining the target sensation intensity modulation voltage comprises determining a voltage of the test voltage ramp being applied when a patient-reported feedback indicating a strongest sensation that the patient can tolerate for a therapeutic dose is received during the application of the test voltage ramp.
6. The method of claim 1 , further comprising determining a minimum patient-detectable modulation voltage that is specific to the patient from the test voltage ramp and further wherein setting the therapeutic dose comprises using the minimum patient-detectable modulation voltage as a starting voltage for the therapeutic dose.
7. The method of claim 6 , wherein determining the minimum patient-detectable modulation voltage comprises receiving patient reported feedback during the application of the test voltage ramp.
8. The method of claim 1 , wherein setting the therapeutic dose comprises setting the therapeutic dose in the implanted neuromodulator or a controller in communication with the implanted neuromodulator.
9. The method of claim 1 , further comprising, prior to setting the therapeutic dose using the estimated peak modulation voltage, setting one or more of: the therapeutic dose duration, the therapy ramp-up time to reach the peak modulation voltage, and the sustained peak modulation time.
10. The method of claim 1 , further comprising setting a high-frequency component of the test voltage ramp applied and setting a high-frequency component of the therapeutic dose to the high-frequency component of the test voltage ramp applied.
11. The method of claim 10 , wherein the high-frequency component of the test voltage ramp applied is between 1 kHz and 100 kHz.
12. The method of claim 1 further comprising setting an alternative therapeutic dose of the neuromodulator implanted into the patient, wherein alternative therapeutic dose comprises an alternative peak modulation voltage that is between about 60% and 95% of the peak modulation voltage.
13. A method of setting a therapeutic dose of a neuromodulator implanted into a patient, wherein the therapeutic dose comprises a therapeutic dose duration including a therapy ramp-up time to reach a peak modulation voltage and a sustained peak modulation time during which a voltage is sustained at the peak modulation voltage, the method comprising:
applying a test voltage ramp from the neuromodulator implanted into the patient;
determining a minimum patient-detectable modulation voltage that is specific to the patient from the test voltage ramp;
determining a target sensation intensity modulation voltage that is specific to the patient from the test voltage ramp, wherein the target sensation intensity modulation voltage is a maximum voltage that the patient can tolerate during application of the test voltage ramp;
calculating an estimated peak modulation voltage as a product of a square root of the target sensation intensity modulation voltage and a function of the therapy ramp-up time to reach the peak modulation voltage, wherein the therapy ramp-up time is a set percentage of the therapeutic dose duration; and
setting the therapeutic dose using the estimated peak modulation voltage and using the minimum patient-detectable modulation voltage as a starting voltage for the therapeutic dose.
14. A system comprising:
an implantable neuromodulator;
a controller for controlling an application of a therapeutic dose by the neuromodulator, wherein the therapeutic dose comprises a therapeutic dose duration including a therapy ramp-up time to reach a peak modulation voltage and a sustained peak modulation time during which a voltage is sustained at the peak modulation voltage, the controller comprising one or more processors;
memory coupled to the one or more processors, the memory configured to store computer-program instructions, that, when executed by the one or more processors, implement a computer-implemented method, the computer-implemented method comprising:
applying a test voltage ramp from the neuromodulator implanted into a patient;
determining a target sensation intensity modulation voltage that is specific to the patient from the test voltage ramp, wherein the target sensation intensity modulation voltage is a maximum voltage that the patient can tolerate during application of the test voltage ramp;
calculating an estimated peak modulation voltage as a square root of a product of the therapy ramp-up time and the target sensation intensity modulation voltage, wherein the therapy ramp-up time is a set percentage of the therapeutic dose duration; and
setting the therapeutic dose using the estimated peak modulation voltage.
15. The system of claim 14 , wherein the target sensation intensity modulation voltage is a maximum patient-tolerable modulation voltage.
16. The system of claim 14 , wherein the therapy ramp-up time to the peak modulation voltage is set to be half of the therapeutic dose duration.
17. The system of claim 14 , wherein the therapeutic dose duration is set to be 30 minutes.
18. The system of claim 14 , wherein determining the target sensation intensity modulation voltage comprises determining a voltage of the test voltage ramp being applied when a patient-reported feedback indicating a strongest sensation that the patient can tolerate for a therapeutic dose is received during the application of the test voltage ramp.
19. The system of claim 14 , wherein the computer-implemented method further comprises: determining a minimum patient-detectable modulation voltage that is specific to the patient from the test voltage ramp and further wherein setting the therapeutic dose comprises using the minimum patient-detectable modulation voltage as a starting voltage for the therapeutic dose.
20. The system of claim 19 , wherein determining the minimum patient-detectable modulation voltage comprises receiving patient reported feedback during the application of the test voltage ramp.
21. The system of claim 14 , wherein setting the therapeutic dose comprises setting the therapeutic dose in the implanted neuromodulator or a controller in communication with the implanted neuromodulator.
22. The system of claim 14 , wherein the computer-implemented method further comprises, prior to setting the therapeutic dose using the estimated peak modulation voltage, setting one or more of: the therapeutic dose duration, the therapy ramp-up time to reach the peak modulation voltage, and the sustained peak modulation time.
23. The system of claim 14 , wherein the computer-implemented method further comprises setting a high-frequency component of the test voltage ramp applied and setting a high-frequency component of the therapeutic dose to the high-frequency component of the test voltage ramp applied.
24. The system of claim 23 , wherein the high-frequency component of the test voltage ramp applied is between 1 kHz and 100 kHz.
25. The system of claim 14 , wherein the computer-implemented method further comprises: setting an alternative therapeutic dose of the neuromodulator implanted into the patient, wherein the alternative therapeutic dose comprises an alternative peak modulation voltage that is between about 60% and 95% of the peak modulation voltage.