System and method to control dorsal root stimulation parameters based on frequency decomposition

Patent metadata

Field	Value
Publication number	US-2016175594-A1
Application number	US-201414577933-A
Country	US
Kind code	A1
Filing date	Dec 19, 2014
Priority date	Dec 19, 2014
Publication date	Jun 23, 2016
Grant date	—

Abstract

A system and method are provided for controlling stimulation of nervous tissue of a patient. The method comprises delivering a stimulation waveform to at least one electrode located proximate to nervous tissue of interest, the stimulation waveform including a series of pulses configured to excite at least one of A-beta (Aβ) fibers, A-delta (Aδ) fibers or C-fibers of the nervous tissue of interest, the stimulation waveform defined by therapy parameters. The method also provides sensing an evoked compound action potential (ECAP) signal from the nervous tissue of interest. The method also analyzes a frequency content of the ECAP signal to obtain ECAP frequency data indicative of activity by at least one type of nerve fibers from a group comprising Aβ, Aδ and C fibers. The method also determines the type of nerve fibers that were activated by the stimulation waveform based on the ECAP frequency data.

First claim

1 . A method to control stimulation of nervous tissue of a patient to treat chronic pain in a patient, the method comprising:
delivering a one or more stimulation waveforms to at least one electrode located proximate to a dorsal root ganglion, the one or more stimulation waveforms including a series of pulses configured to excite beta (Aβ) fibers, A-delta (Aδ) fibers and C-fibers of the dorsal root ganglion, the one or more stimulation waveforms defined by therapy parameters; sensing an evoked compound action potential (ECAP) signal from the dorsal root ganglion; analyzing a frequency content of the ECAP signal to obtain ECAP frequency data indicative of activity by Aβ, Aδ and C fibers; and determining the type of nerve fibers that were activated by the one or more stimulation waveforms based on the ECAP frequency data; delivering stimulation pulses to the dorsal root ganglion to treat chronic pain of the patient according to therapy parameters, selected in response to the determining, that activate Aβ fibers and reduce activation of Aδ and C fibers.

2 . The method of claim 1 , wherein the ECAP frequency data includes Aβ, Aδ and C fiber components, the determining operation identifying an amount of activity exhibited by at least one of the Aβ, Aδ and C fiber components in response to the one or more stimulation waveforms.

3 . The method of claim 1 , wherein the analyzing operation includes using a fast Fourier transform to convert the ECAP signal to a frequency domain, the ECAP frequency data including clusters of frequency domain components distributed along a frequency spectrum, where each of the clusters is associated with one of the Aβ, Aδ and C nerve fibers.

4 . The method of claim 1 , wherein the ECAP signal represents ECAP recorded activity from afferent neurons carrying both painful stimuli, within the Aδ and C fibers, and non-painful stimuli, within the Aβ fibers.

5 . The method of claim 1 , further comprising adjusting at least one of the therapy parameters based on the ECAP frequency data.

6 . The method of claim 5 , wherein the adjusting operation selects between a burst, high frequency, tonic or random pattern stimulation waveforms based upon which of the burst, high frequency, tonic or random pattern stimulation waveforms results in a selected level of activation for a target one or more of the Aβ, Aδ or C fibers.

7 . The method of claim 5 , wherein the analyzing operation uses a fast Fourier transform on the ECAP signals to define clusters of frequency domain components within the ECAP frequency data, the adjusting operation adjusting the stimulation parameters based on the clusters of frequency domain components to maintain a select amount of activation of a select one or more of the types of nerve fibers.

8 . The method of claim 1 , further comprising defining thresholds for activating at least one of the Aβ, Aδ or C fibers based on the ECAP frequency data and the one or more stimulation waveforms.

9 . The method of claim 1 , wherein the one or more stimulation waveforms are delivered with a collection of test pulses having at least one of different amplitudes and pulse widths, the method further comprising establishing thresholds in connection with excitation of the Aβ, Aδ or C fibers based on first detection of frequency domain components in the ECAP frequency data indicating activity of the corresponding Aβ, Aδ or C fibers.

10 . The method of claim 1 , wherein the therapy parameters define at least one of a burst stimulation waveform or a high frequency stimulation waveform.

11 .- 20 . (canceled)

Assignees

• Pacesetter Inc

Inventors

• Min Xiaoyi
• Goodman Keiser Melanie
• Hou Wenbo
• Morley Bruce A

Classifications

• A61N1/36178

  Burst or pulse train parameters · CPC title

• A61N1/36071 Primary

  Pain · CPC title

• A61N1/3615

  Intensity · CPC title

• A61N1/36171

  Frequency · CPC title

• A61N1/36135

  using physiological parameters · CPC title