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.

What is claimed is: 
     
         1 . An implantable neurostimulator for use in a patient having obstructive sleep apnea, the neurostimulator comprising:
 a case;   stimulation circuitry contained within the case, the stimulation circuitry configured for generating an electrical pulse train;   sensing circuitry comprising at least one sensor affixed directly to or within the case, the at least one sensor configured for sensing physiological artifacts that are caused by respiration; and   control circuitry contained within the case, the control circuitry configured for causing the stimulation circuitry to deliver the electrical pulse train to at least one electrode contact in synchronization with a respiratory cycle based on the sensed physiological artifacts.   
     
     
         2 . The neurostimulator of  claim 1 , further comprising a receptacle configured for receiving at least one proximal contact of an electrode lead that carries the at least one electrode contact. 
     
     
         3 . The neurostimulator of  claim 1 , wherein the at least one sensor comprises at least one of a pressure sensor and an inertial sensor. 
     
     
         4 . The neurostimulator of  claim 1 , wherein the control circuitry is configured for determining the next projected onset of an inspiratory phase of the respiratory cycle based on the sensed physiological artifacts, and causing the stimulation circuitry to deliver 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. 
     
     
         5 . The neurostimulator of  claim 1 , further comprising memory configured for storing data representative of the physiological artifacts sensed by the at least one sensor. 
     
     
         6 . The neurostimulator of  claim 1 , wherein the electrical pulse train has an initial, preconditioning current or voltage amplitude and a subsequent higher stimulating current or voltage amplitude. 
     
     
         7 . The neurostimulator of  claim 1 , further comprising a motion detector affixed directly to or within the case, the motion detector configured for sensing a tap on the neurostimulator, wherein the control circuitry is configured for toggling the neurostimulator between an ON position and an OFF position in response at least one tap, such that in the OFF position, no stimulation energy is delivered to the at least one electrode contact. 
     
     
         8 . The neurostimulator of  claim 7 , wherein the at least one sensor comprises the motion detector. 
     
     
         9 . The neurostimulator of  claim 8 , wherein the control circuitry is configured for toggling the neurostimulator between an ON position and an OFF position in response to a plurality of successive taps. 
     
     
         10 . The neurostimulator of  claim 9 , wherein the control circuitry is configured for toggling the neurostimulator between an ON position and an OFF position in response to a plurality of successive taps less than one second apart. 
     
     
         11 . A neurostimulation system, comprising:
 an electrode lead carrying the at least one electrode contact; and   the neurostimulator of  claim 2 , wherein the receptacle is configured for receiving the electrode lead.   
     
     
         12 . The neurostimulation system of  claim 11 , wherein the electrode lead carries a plurality of electrode contacts, the neurostimulation system further comprising a clinician programmer configured for selecting the at least one electrode contact from the electrode contacts, transcutaneously communicating with the neurostimulator, and programming the control circuitry to deliver the electrical pulse train to the selected at least one electrode contact. 
     
     
         13 . The neurostimulation system of  claim 12 , further comprising a patient programmer configured for transcutaneously communicating with the neurostimulator, and toggling the neurostimulator between the OFF position and the ON position. 
     
     
         14 . The neurostimulation system of  claim 12 , wherein the neurostimulator further comprises a rechargeable battery contained within the case, the neurostimulation system further comprising an external charger configured for inductively and transcutaneously charging the rechargeable battery of the neurostimulator.