Stimulator systems and methods for obstructive sleep apnea

Abstract

An electrode lead comprises an electrically insulative cuff body and at least three axially aligned electrode contacts circumferentially disposed along the inner surface of the cuff body when in the furled state. The electrode contacts may be circumferentially disposed around a nerve, and an electrical pulse train may be delivered to the electrode contacts thereby stimulating the nerve to treat obstructive sleep apnea. The electrical pulse train may be one that pre-conditions peripherally located nerve fascicles to not be stimulated, while stimulating centrally located nerve fascicles. A feedback mechanism can be used to titrate electrode contacts and electrical pulse train to the patient. A sensor that is affixed to the case of a neurostimulator can be used to measure physiological artifacts of respiration, and a motion detector can be used to sense tapping of the neurostimulator to toggle the neurostimulator between an ON position and an OFF position.

1 . An electrode lead, comprising:
 an elongated lead body having a proximal end and a distal end;   at least three connector contacts affixed to the proximal end of the lead body;   a biologically compatible, flexible, electrically insulative cuff body affixed to the distal end of the lead body, the cuff body pre-shaped to transition from an unfurled state to a furled state, wherein the cuff body, when in the furled state has an inner surface for contacting a nerve;   at least three axially aligned electrode contacts circumferentially disposed along the inner surface of the cuff body when in the furled state; and   at least three electrical conductors extending through the lead body respectively between the at least three connector contacts and the at least three electrode contacts.   
     
     
         2 . The electrode lead of  claim 1 , wherein the inner surface of the furled cuff body has a diameter in the range of 2.5 mm to 4.0 mm. 
     
     
         3 . The electrode lead of  claim 1 , wherein the at least three electrode contacts comprise at least six electrode contacts. 
     
     
         4 . The electrode lead of  claim 1 , wherein, when the cuff body is in the furled state, the electrode contacts circumferentially span at least a 180-degree arc around the inner surface of the cuff body. 
     
     
         5 . The electrode lead of  claim 1 , wherein, when the cuff body is in the furled state, the electrode contacts circumferentially span at least a 270-degree arc around the inner surface of the cuff body. 
     
     
         6 . The electrode lead of  claim 1 , wherein, when the cuff body is in the unfurled state, a center-to-center spacing of each pair of adjacent ones of electrode contacts is equal to or less than twice the width of each electrode contact of the respective pair of electrode contacts. 
     
     
         7 . The electrode lead of  claim 1 , wherein the lead body has at least one portion that is S-shaped to provide strain relief. 
     
     
         8 . The electrode lead of  claim 1 , wherein the cuff body is self-adjusting, such that the cuff body accommodates different sized nerve diameters, and diameter changes over time. 
     
     
         9 . A neurostimulation system, comprising:
 the electrode lead of  claim 1 ; and   a neurostimulator comprising a connector configured for receiving the proximal contacts of the electrode lead, stimulation circuitry configured for generating an electrical pulse train, and control circuitry configured for causing the stimulation circuitry to deliver the electrical pulse train to at least one of the electrode contacts of the electrode lead.   
     
     
         10 . A method of using the electrode lead of  claim 1 , comprising:
 maintaining the cuff body in the unfurled state while placing the cuff body in contact with the nerve;   placing the cuff body from the unfurled state into the furled state, such that the cuff body wraps around the nerve; and   delivering an electrical pulse train to at least one of the electrode contacts of the electrode lead, thereby stimulating the nerve.   
     
     
         11 . A neurostimulation system, comprising:
 an electrode lead having a lead body, and a biologically compatible electrically insulative cuff body affixed to distal end of the lead body, the cuff body pre-shaped and flexible to transition from an unfurled state to a furled state, wherein the cuff body, when in the furled state has an inner surface for contacting a nerve, the electrode lead further comprising at least three axially aligned electrode contacts circumferentially disposed along the inner surface of the cuff body when in the furled state; and   a neurostimulator configured for delivering an electrical pulse train to at least one of the electrode contacts of the electrode lead.   
     
     
         12 . The neurostimulation system of  claim 11 , wherein the inner surface of the furled cuff body has a diameter in the range of 2.5 mm to 4.0 mm. 
     
     
         13 . The neurostimulation system of  claim 11 , wherein the at least three electrode contacts. 
     
     
         14 . The neurostimulation system of  claim 11 , wherein, when the cuff body is in the furled state, the electrode contacts circumferentially span at least a 180-degree arc around the inner surface of the cuff body. 
     
     
         15 . The neurostimulation system of  claim 11 , wherein, when the cuff body is in the furled state, the electrode contacts circumferentially span at least a 270-degree arc around the inner surface of the cuff body. 
     
     
         16 . The neurostimulation system of  claim 11 , wherein, when the cuff body is in the unfurled state, a center-to-center spacing of each pair of adjacent ones of electrode contacts is equal to or less than twice the width of each electrode contact of the respective pair of electrode contacts. 
     
     
         17 . The neurostimulation system of  claim 11 , wherein the lead body has at least a portion that is S-shaped to provide strain relief. 
     
     
         18 . The neurostimulation system of  claim 11 , wherein the cuff body is self-adjusting, such that the cuff body accommodates different sized nerve diameters, and diameter changes over time. 
     
     
         19 . The neurostimulation system of  claim 11 , wherein the at least one electrode contact comprises a pair of adjacent ones of the electrode contacts, and the neurostimulator is configured for delivering the electrical pulse train between the pair of adjacent ones of the electrode contacts in a bipolar mode. 
     
     
         20 . The neurostimulation system of  claim 11 , wherein the neurostimulator is further configured for sensing physiological artifacts that are caused by respiration, and delivering the electrical pulse train to the at least one electrode contact in synchronization with a respiratory cycle based on the sensed physiological artifacts. 
     
     
         21 . The neurostimulation system of  claim 20 , wherein the neurostimulator is configured for determining the next projected onset of an inspiratory phase of the respiratory cycle based on the sensed physiological artifacts, and delivering the electrical pulse train to the at least one electrode contact immediately before, at, or right after the next projected onset of the inspiratory phase of the respiratory cycle. 
     
     
         22 . The neurostimulation system of  claim 20 , wherein the neurostimulator is configured for storing data representative of the physiological artifacts sensed by the sensing circuitry. 
     
     
         23 . The neurostimulation system of  claim 11 , wherein the electrical pulse train has an initial, preconditioning current or voltage amplitude and a subsequent higher stimulating current or voltage amplitude. 
     
     
         24 . The neurostimulation system of  claim 11 , further comprising a clinician programmer configured for selecting the at least one electrode contact from the electrode contacts, and transcutaneously communicating with the neurostimulator, and programming the neurostimulator to deliver the electrical pulse train to the selected at least one electrode contact. 
     
     
         25 . The neurostimulation system of  claim 11 , further comprising a patient programmer configured for transcutaneously communicating with the neurostimulator, and toggling the neurostimulator between an OFF position and an ON position, such that in the OFF position, no stimulation is delivered. 
     
     
         26 . The neurostimulation system of  claim 11 , further comprising an external charger configured for inductively and transcutaneously charging the neurostimulator. 
     
     
         27 . The neurostimulation system of  claim 11 , further comprising a feedback mechanism configured for measuring a physiological parameter of the patient indicative of the efficacy of the delivered electrical pulse train in treating obstructive sleep apnea of a patient. 
     
     
         28 . The neurostimulation system of  claim 27 , wherein the feedback mechanism comprises one or more temperature sensors configured for measuring the temperature of inhaled and exhaled air of a patient, one or more carbon dioxide (CO2) sensors configured for measuring a concentration of CO2 in inhaled and exhaled air of the patient, one or more electro-myographic (EMG) sensors configured for measuring the electrical potential generated by the muscle cells of a tongue of the patient, one or more cameras configured for capturing pictures of the airway of the patient, or one or more inertial sensors configured for measuring the movement of the tongue of the patient. 
     
     
         29 . The neurostimulation system of  claim 27 , further comprising a clinician programmer configured for computing a score of the at least one electrode based on the measured physiological parameter. 
     
     
         30 . A method of stimulating a nerve of a patient to treat an ailment, comprising:
 circumferentially disposing at least three axially aligned electrode contacts around the nerve; and   delivering an electrical pulse train to at least one of the electrode contacts, thereby stimulating the nerve to treat the ailment.   
     
     
         31 .- 155 . (canceled)