Abstract:
Some embodiments provide a system for delivering neurostimulation. Some system embodiments comprise a lead configured to be implanted in the body, a stimulation output circuit configured to deliver neurostimulation pulses to the vagus nerve through the lead, an EMG sensing circuit configured to use the lead to sense EMG signals from laryngeal muscle activity, and an evoked muscular response detection circuit configured to use the EMG signals sensed by the EMG sensing circuit to detect evoked laryngeal muscle activity evoked by the neurostimulation pulse.
Abstract:
Implanted electrodes can be used to deliver electrical stimulation signals to areas near blood vessels, nerves, or other internal body locations. In an example, an electrode can be implanted in a cervical location and can be used to measure dimensional changes in an artery using impedance plethysmography. Measured artery dimensional changes can be used to determine one or more physiological parameters associated with a patient's health status, such as pulse transit time, relative pulse pressure, or aterial compliance, among others. These parameters can be used to monitor a patient health status or to modulate a patient's therapy, among other uses. In some examples, an electrode configured to deliver an electrostimulation signal to nerve tissue can be used to provide non-neurostimulating electrical stimulation plethysmography signals near a blood vessel.
Abstract:
A neurostimulation system includes a neural stimulation lead having a proximal portion and a distal portion and including a plurality of electrodes along the distal portion. The plurality of electrodes are configured for positioning proximate a portion of the autonomic nervous system. A neural stimulation circuit, coupled to the plurality of electrodes, delivers neural stimulation pulses to the plurality of electrodes. A processor and controller is configured to control the neural stimulation circuit to deliver first neural stimulation pulses to each of a plurality of electrode configurations. Each electrode configuration includes one or more of the plurality of electrodes. The processor and controller is further configured to receive information related to motor fiber activity that is induced in response to delivery of the first neural stimulation pulses to each of the plurality of electrode configurations and to identify the electrode configurations that induce the motor fiber activity.
Abstract:
A system including two neurostimulation leads can be used for stimulating a select region of a nerve within a nerve bundle. For example, two leads can be used to stimulate a select region of the vagus nerve located within a patient's carotid sheath. The first neurostimulation is positioned within the carotid sheath and the second neurostimulation lead is positioned external to the carotid sheath. Each of the first and second neurostimulation leads includes at least one electrode defining an electrode array about the select region of the nerve. The electrode array, and more particularly, the different possible electrode vector combinations provided by the first and second neurostimulation leads facilitate steering of stimulation current density fields as needed or desired between the electrodes to effectively and efficiently treat a particular medical, psychiatric, or neurological disorder.
Abstract:
One or more temporal stimulation parameters of vagus nerve stimulation (VNS) are selected to substantially modulate one or more target physiological functions without substantially modulating one or more non-target physiological functions. In one embodiment, a stimulation duty cycle is selected such that VNS is delivered to the cervical vagus nerve trunk to modulate a cardiovascular function without causing laryngeal muscle contractions.
Abstract:
Some embodiments provide a method, comprising performing a neural stimulation test routine for stimulating a neural target in a cervical region of a patient, wherein for each of a plurality of head positions, performing the neural stimulation test routine includes testing a plurality of electrode configurations. The method further comprises recording threshold data for each of the tested electrode configurations for the plurality of head positions, and recommending an electrode configuration based on the recorded threshold data.
Abstract:
One or more temporal stimulation parameters of vagus nerve stimulation (VNS) are selected to substantially modulate one or more target physiological functions without substantially modulating one or more non-target physiological functions. In one embodiment, a stimulation duty cycle is selected such that VNS is delivered to the cervical vagus nerve trunk to modulate a cardiovascular function without causing laryngeal muscle contractions.
Abstract:
A neurostimulation system delivers neurostimulation to a patient using one or more primary parameters and one or more secondary parameters. The one or more primary parameters are controlled for maintaining efficacy of the neurostimulation. The one or more secondary parameters are adjusted for preventing the patient from developing neural accommodation. In various embodiments, values for the one or more secondary parameters are varied during the delivery of the neurostimulation for prevention of neural accommodation that may result from a constant or periodic pattern of stimulation pulses.
Abstract:
A two-part system for securing and stabilizing a lead at a location within a patient's internal jugular vein adjacent a region of the vagus nerve to be stimulated is described. The two-part system includes a lead and a stent-like fixation member that is provided separate from the lead. The stent-like fixation member is used to secure an electrode region of the lead at a location within the internal jugular vein adjacent the vagus nerve. The stent-like fixation member urges the electrode region of the lead against the vessel walls of the internal jugular vein such that at least one electrode is oriented in a direction towards the vagus nerve. In one example, the stent-like fixation member includes a channel sized to receive and retain a portion of the lead therein.
Abstract:
A neurostimulation system provides for capture verification and stimulation intensity adjustment to ensure effectiveness of vagus nerve stimulation in modulating one or more target functions in a patient. In various embodiments, stimulation is applied to the vagus nerve, and evoked responses are detected to verify that the stimulation captures the vagus nerve and to adjust one or more stimulation parameters that control the stimulation intensity.