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WO2024189520A1 - Commande de thérapie basée sur la détermination du mouvement de la langue - Google Patents

Commande de thérapie basée sur la détermination du mouvement de la langue Download PDF

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Publication number
WO2024189520A1
WO2024189520A1 PCT/IB2024/052342 IB2024052342W WO2024189520A1 WO 2024189520 A1 WO2024189520 A1 WO 2024189520A1 IB 2024052342 W IB2024052342 W IB 2024052342W WO 2024189520 A1 WO2024189520 A1 WO 2024189520A1
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WO
WIPO (PCT)
Prior art keywords
signals
patient
imd
processing circuitry
therapy
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
PCT/IB2024/052342
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English (en)
Inventor
Erik J. Peterson
Leonid M. Litvak
Avram Scheiner
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Medtronic Inc
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Medtronic Inc
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Publication date
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Publication of WO2024189520A1 publication Critical patent/WO2024189520A1/fr
Anticipated expiration legal-status Critical
Pending legal-status Critical Current

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Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00—Electrotherapy; Circuits therefor
    • A61N1/18—Applying electric currents by contact electrodes
    • A61N1/32—Applying electric currents by contact electrodes alternating or intermittent currents
    • A61N1/36—Applying electric currents by contact electrodes alternating or intermittent currents for stimulation
    • A61N1/3605—Implantable neurostimulators for stimulating central or peripheral nerve system
    • A61N1/3606—Implantable neurostimulators for stimulating central or peripheral nerve system adapted for a particular treatment
    • A61N1/3611—Respiration control
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/103—Measuring devices for testing the shape, pattern, colour, size or movement of the body or parts thereof, for diagnostic purposes
    • A61B5/11—Measuring movement of the entire body or parts thereof, e.g. head or hand tremor or mobility of a limb
    • A61B5/1107—Measuring contraction of parts of the body, e.g. organ or muscle
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
    • A61B5/316—Modalities, i.e. specific diagnostic methods
    • A61B5/389—Electromyography [EMG]
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/48—Other medical applications
    • A61B5/4806—Sleep evaluation
    • A61B5/4818—Sleep apnoea
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00—Electrotherapy; Circuits therefor
    • A61N1/02—Details
    • A61N1/04—Electrodes
    • A61N1/05—Electrodes for implantation or insertion into the body, e.g. heart electrode
    • A61N1/0526—Head electrodes
    • A61N1/0548—Oral electrodes
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00—Electrotherapy; Circuits therefor
    • A61N1/18—Applying electric currents by contact electrodes
    • A61N1/32—Applying electric currents by contact electrodes alternating or intermittent currents
    • A61N1/36—Applying electric currents by contact electrodes alternating or intermittent currents for stimulation
    • A61N1/3605—Implantable neurostimulators for stimulating central or peripheral nerve system
    • A61N1/36128—Control systems
    • A61N1/36135—Control systems using physiological parameters
    • A61N1/36139—Control systems using physiological parameters with automatic adjustment

Definitions

  • This disclosure relates to medical device systems and, more particularly, to medical device systems for delivery of electrical stimulation therapy.
  • Obstructive sleep apnea which encompasses apnea and hypopnea, is a disorder in which breathing may be irregularly and repeatedly stopped and started during sleep, resulting in disrupted sleep and reduced blood oxygen levels. Muscles in a patient’s throat intermittently relax thereby allowing the tongue to obstruct the upper airway while sleeping and cause OSA. For example, airflow into the upper airway can be obstructed by the tongue or soft palate moving to the back of the throat and covering the airway. Uoss of air flow also causes unusual inter-thoracic pressure as a person tries to breathe with a blocked airway.
  • Uack of adequate levels of oxygen during sleep can contribute to abnormal heart rhythms, heart attack, heart failure, high blood pressure, stroke, memory problems, and increased accidents during the day due to inadequate sleep. Additionally, loss of sleep occurs when a person is awakened during an apneic episode.
  • the devices, systems, and techniques of this disclosure generally relate to a medical device system and methods for therapy for obstructive sleep apnea (OSA) but can be extended to address other patient symptoms and disorders.
  • OSA obstructive sleep apnea
  • Some example techniques to address OSA include electrically stimulating one or both hypoglossal nerves and/or motor points (e.g., such as where the hypoglossal nerves make contact with muscle) in the tongue of the patient.
  • the hypoglossal nerve(s) causes protrusor muscles (e.g., genioglossus and geniohyoid muscles) to contract and move the tongue forward, thereby opening the airway.
  • protrusor muscles e.g., genioglossus and geniohyoid muscles
  • processing circuitry e.g., of the IMD or other device
  • the one or more sensed signals include at least one of a compound muscle action potential (CMAP) sensed by a lead implanted within the tongue of the patient, or an electromyography (EMG) signal sensed by the lead.
  • CMAP compound muscle action potential
  • EMG electromyography
  • the processing circuitry may control the OSA therapy state (e.g., such as being ON, OFF, SNOOZE, DELAY, etc.) based on whether the tongue movement is volitional or not. For example, it may be undesirable to provide OSA therapy when the patient is in volitional control of their tongue (e.g., when the patient is awake and functioning normally).
  • the electrical stimulation of the hypoglossal nerve may cause the tongue of the patient to move, but if the patient already has volitional control of their tongue, then delivery of electrical stimulation may not be needed since the patient can volitionally keep the tongue forward.
  • the processing circuitry may control the OSA therapy state automatically based on whether the tongue movement is volitional or not. In some examples, the processing circuitry may control the OSA therapy state in response to sensing one or more specific volitional tongue motions from the patient.
  • a system includes a memory and processing circuitry coupled to the memory, the processing circuitry configured to: receive, via one or more electrodes, one or more signals from patient tissue; determine whether the one or more signals from the patient tissue are indicative of volitional movement of a tongue of a patient; and control therapy of an implantable medical device (IMD) configured to deliver therapy for sleep apnea based on the determination.
  • IMD implantable medical device
  • a method includes: receiving, via one or more electrodes, one or more signals from patient tissue; determining whether the one or more signals from the patient tissue are indicative of volitional movement of a tongue of the patient; and controlling therapy of an IMD configured to deliver therapy for sleep apnea based on the determination.
  • a computer-readable storage medium stores instructions thereon that when executed cause one or more processors to: receive, via one or more electrodes, one or more signals from patient tissue; determine whether the one or more signals from the patient tissue are indicative of volitional movement of a tongue of a patient; and control therapy of an implantable medical device (IMD) configured to deliver therapy for sleep apnea based on the determination.
  • IMD implantable medical device
  • FIG. 1 is a conceptual diagram of an implantable medical device (IMD) system for delivering obstructive sleep apnea (OSA) therapy.
  • IMD implantable medical device
  • OSA obstructive sleep apnea
  • FIG. 2 is a conceptual diagram illustrating an example location of lead implantation for stimulation for OSA therapy and sensing of one or more signals in tissue of the patient.
  • FIG. 3 is a block diagram illustrating example configurations of implantable medical devices (IMDs) which may be utilized in the system of FIG. 1.
  • IMDs implantable medical devices
  • FIG. 4 is a block diagram illustrating an example configuration of an external device.
  • FIG. 5 is an example graph illustrating example CMAP signals and EMG signals.
  • FIG. 6 is an example graph illustrating a first CMAP signal and a second CMAP signal.
  • FIG. 7 is a flowchart illustrating an example of method of controlling therapy of an IMD, in accordance with examples of the disclosure.
  • This disclosure describes examples of medical devices, systems, and techniques for adapting a therapy state for an IMD configured to provide obstructive sleep apnea (OSA) therapy.
  • OSA obstructive sleep apnea
  • electrical stimulation may be delivered to cause the tongue and other soft tissues of a patient to enter an advanced state or increase rigidity (e.g., activated state), during sleep, to avoid or reduce upper airway obstruction.
  • activated state with regard to the tongue refers to a position of the tongue that is not in a relaxed position of the tongue.
  • the tongue is in a normal place where airflow happens with relative ease.
  • activated state is an advanced state where a position of the tongue is moved forward and/or downward compared to a non-stimulated position or a relaxed position of the tongue.
  • a patient may activate a therapy program of the IMD (change a therapy state of the IMD to an ON therapy state) when heading to bed to allow the IMD to provide OSA therapy (e.g., electrical stimulation therapy) while the patient is asleep, and the patient may deactivate the therapy program (change the therapy state to an OFF therapy state) after waking.
  • OSA therapy e.g., electrical stimulation therapy
  • the patient may forget to activate or deactivate the therapy program, unintentionally activate or deactivate the therapy program, or activate the therapy program even if the patient does not immediately go to sleep.
  • a patient may wish to control a therapy state of the IMD when control instruments are not immediately available.
  • processing circuitry of an IMD may control (e.g., alter) the IMD’s therapy state in response to measurement of patient physiological parameters (e.g., sensed signals).
  • patient physiological parameters e.g., sensed signals
  • the IMD may ensure that OSA therapy is provided to the patient when it is needed, and not provided when not needed, such as when therapy may interfere with the patient’s day-to-day activities.
  • an IMD may receive one or more signals from patient tissue, determine whether the one or more signals are indicative of volitional movement of a tongue of the patient, and control therapy of the IMD configured to deliver sleep apnea therapy based on the determination.
  • processing circuitry of the IMD may be configured to automatically change a therapy state of the IMD to an appropriate therapy state without patient input. In some examples, processing circuitry of the IMD may be configured to change a therapy state of the IMD based on specific volitional tongue movements performed by the patient to control the therapy state of the IMD.
  • Some techniques may rely upon posture information, breathing measurements, time of day, etc. to determine whether the patient is sleeping or awake, and control therapy accordingly. However, such techniques may potentially result in incorrect determination of whether the patient is asleep or awake, and whether to deliver therapy or not. By determining patient desire indicated by volitional input via the tongue, in addition to or instead of some other techniques, there may be a higher likelihood of proper determination of whether to deliver therapy or not.
  • the IMD may receive the one or more signals from patient tissue by sensing the one or more signals using one or more electrodes on one or more leads of the IMD.
  • the one or more signals may include electromyography (EMG) signals and/or compound muscle action potential (CMAP) signals indicative of patient tongue motion.
  • EMG electromyography
  • CMAP compound muscle action potential
  • the one or more leads may be implanted within the tongue of the patient and the one or more electrodes may be disposed in close proximity to a hypoglossal nerve of the patient.
  • the IMD may be configured to deliver, via stimulation circuitry using the one or more electrodes, one or more electrical stimulation pulses to the patient tissue.
  • the one or more electrodes may sense one or more evoked signals (e.g., CMAP) from the patient tissue evoked in response to the delivery of the one or more electrical stimulation pulses.
  • CMAP compound muscle action potential
  • the processing circuitry of the IMD may compare the one or more signals to one or more sets of reference signal data stored in a database in memory known to correspond to volitional movement of the tongue of the patient. The processing circuitry may determine, based at least in part on the comparison, whether the one or more signals are indicative of volitional movement of the tongue of the patient. In some examples, the processing circuitry may determine that the one or more signals from patient tissue satisfy a threshold similarity with one or more sets of reference signal data stored in memory known to correspond to volitional movement. In response, the processing circuitry may determine that the one or more signals are indicative of volitional movement of the tongue of the patient.
  • processing circuitry may determine that the one or more signals from patient tissue do not satisfy a threshold similarity with one or more sets of reference signal data stored in memory known to correspond to volitional movement. In response, the processing circuitry may determine that the one or more signals are not indicative of volitional movement of the tongue of the patient.
  • the processing circuitry may utilize machine learning based techniques.
  • a machine learning device e.g., not necessarily the IMD
  • the machine learning device may receive the reference signal data known to correspond to volitional movement of the tongue.
  • the machine learning device may train a neural network to generate a trained neural network that identifies whether a sensed signal corresponds to volitional movement or not.
  • the IMD or another device like a programmer may store the trained neural network.
  • the input to the trained neural network may be the sensed signal, and the output from the trained neural network may be information indicative of whether the one or more signals, from the patient tissue, are indicative of volitional movement of the tongue of the patient.
  • the processing circuitry may control (e.g., change) a therapy state of the IMD.
  • the processing circuitry may change a therapy state of the IMD from an ON therapy state to an OFF therapy state, wherein in the OFF therapy state the IMD is configured to not deliver electrical stimulation for treating sleep apnea.
  • the processing circuitry may change a therapy state of the IMD from an ON therapy state to a DELAY therapy state, wherein in the DELAY therapy state, the IMD is configured to wait a period of time before delivering electrical stimulation for treating sleep apnea to patient tissue. For example, in the DELAY therapy state the IMD may wait for ten minutes before automatically reverting to the ON therapy state.
  • the IMD may receive instructions to change the therapy state.
  • a system may include an external device (e.g., a smartphone or other computing device) and the IMD.
  • the patient or a physician may interact with a user interface of the external device to send instructions to the IMD to change a therapy state of the IMD to an ON therapy state.
  • a patient may be ready to sleep, and may want to begin OSA therapy.
  • processing circuitry of the IMD may change the therapy state to the DELAY therapy state. In this way, the IMD may give the patient time to fall asleep before automatically changing to the ON therapy state.
  • the IMD may interpret volitional movements of the tongue by the patient as instructions to change the therapy state.
  • the external device normally used to send instructions to the IMD may not be easily accessible by the patient, or the patient may wish to change the therapy state without taking the time to access the external device.
  • the processing circuitry of the IMD may determine that no signals have been received from patient tissue over a time period. This may indicate, for example, that the tongue has not moved over the time period and the patient may be asleep.
  • the processing circuitry may change the therapy state of the IMD to the ON therapy state.
  • the processing circuitry may change the therapy state from an OFF therapy state to the ON therapy state, a DELAY therapy state to the ON therapy state, or from any other therapy state to the ON therapy state.
  • the processing circuitry of the IMD may perform a calibration. For example, the processing circuitry may change the therapy state of the IMD to a CALIBRATION therapy state, wherein the processing circuitry sends instructions to a display device of an external device to display one or more sets of instructions that instruct the patient to engage in one or more actions designed to elicit a set of signals known to correspond to volitional tongue movement.
  • the processing circuitry sense the signals received in response to the patient performing the one or more actions, and may store the set of signals known to correspond to volitional tongue movement in a database in memory.
  • the set of signals known to correspond to volitional tongue movement can be used to retrain or update the neural network model to generate an updated trained neural network model.
  • the processing circuitry may save volitional tongue movements to the database in memory as control inputs to change a therapy state of the IMD in response to the volitional tongue movements.
  • the IMD may be in an ON therapy state to provide OSA therapy to the tongue of the patient by causing stimulation circuitry of the IMD to deliver a stimulation signal to patient tissue.
  • the stimulation signal may evoke one or more evoked signals from the patient tissue indicative of the non-volitional movement of the tongue caused by the stimulation signal.
  • the stimulation signal used to evoke the one or more evoked signals may be therapeutic, but need not necessarily be therapeutic. That is, the stimulation signal may be delivered for evoking an evoked signal, without necessarily providing therapy.
  • the processing circuitry may be configured to determine that the one or more signals were received from patient tissue within a threshold amount of time after delivery of the stimulation signal. In response to determining that the one or more signals were received from patient tissue within a threshold amount of time after deliver of the stimulation signal, the processing circuitry may determine that the one or more signals are not indicative of volitional movement of the tongue.
  • the IMD may conserve battery life by not sensing for signals from patient tissue or delivering stimulation signals to patient tissue for a period of time in which it is unlikely that the patient will need stimulation therapy.
  • the processing circuitry of the IMD may sense two or more sets of signals from the patient tissue within a threshold amount of time from one another, indicating potential volitional movement of the tongue. In response to sensing the two or more sets of signals within the threshold amount of time, the processing circuitry may change the therapy state of the IMD to a SNOOZE therapy state, in which the processing circuitry does not sense for signals from the patient tissue for a period of time.
  • the IMD may include or be in communication with other devices that provide information that may assist the IMD in determining whether the one or more signals are indicative of volitional movement of the tongue of the patient.
  • a system including the IMD may also include a clock to track the time of day, one or more accelerometers to track patient movement (e.g., walking, breathing, etc.), a heart rate monitor or other sensor to sense physiological data of the patient, etc.
  • the time of day may be considered when determining whether the patient is likely to be asleep or awake, and furthermore whether the one or more signals are likely to be indicative of volitional movement.
  • the IMD may provide more effective OSA therapy to a patient.
  • the processing circuitry may prevent patient discomfort by only providing OSA therapy when the patient is asleep.
  • the IMD may further have improved performance over other devices that provide OSA therapy by conserving power when OSA therapy is not needed for the patient.
  • the IMD may further allow a patient to change a therapy state of the IMD through volitional tongue movements.
  • FIG. 1 is a conceptual diagram of a medical system for delivering OSA therapy.
  • implantable medical device (IMD) 16 and lead 20 are implanted in patient 14.
  • IMD 16 includes housing 15 enclosing circuitry of IMD 16.
  • IMD 16 includes connector assembly 17, which is hermetically sealed to housing 15 and includes one or more connector bores for receiving a proximal end of at least one medical electrical lead 20 used for delivering OSA therapy.
  • lead 20 is illustrated in FIG. 1, there may be one or more leads 20 to which IMD 16 is coupled.
  • FIG. 1 illustrates the location of IMD 16 as being within or proximate to the neck of patient 14.
  • IMD 16 may be implanted in various other locations.
  • the surgeon may implant IMD 16 in the left or right pectoral region.
  • the surgeon may plan on implanting IMD 16 in the left pectoral region unless another medical device is already implanted in the left pectoral region. If another medical device is already implanted in the left pectoral region, the surgeon may then implant IMD 16 in the right pectoral region.
  • There may other locations where the surgeon may implant IMD 16 such as the back of patient 14, and other locations in the head such as below and behind an ear, or in the chin, etc.
  • the example techniques are not limited to any particular implant location of IMD 16.
  • IMD 16 may not be implanted within patient 14, for example with lead 20 passing through patient 14’s skin to an implant site for lead 20.
  • Lead 20 may include a flexible, elongated lead body 22, also called elongated member 22, that extends from lead proximal end 24 to lead distal end 26.
  • lead 20 includes one or more electrodes 30 that are carried along a lead distal portion adjacent lead distal end 26 and are configured for implant within the protrusor muscles 42A, 42B, and 46 of tongue 40.
  • the genioglossus muscle includes oblique compartment 42A and horizontal compartment 42B.
  • the genioglossus muscle is referred to as protrusor muscle 42.
  • Protrusor muscle 46 is an example of the geniohyoid muscle.
  • FIG. 1 illustrates one set of protrusor muscles 42 and 46 (e.g., on a first side of tongue 40).
  • the other side of tongue 40 also includes protrusor muscles.
  • a left side of tongue 40 includes a first set of protrusor muscles 42 and 46
  • a right side of tongue 40 includes a second set of protrusor muscles.
  • IMD 16 may deliver OSA therapy to a first side of tongue 40 for a first time period, then deliver the OSA therapy to a second side of tongue 40 for a second time period. By switching back and forth between different sides of the tongue when providing OSA therapy, IMD may prevent excessive tongue fatigue.
  • a surgeon may implant one or more leads 20 such that one or more electrodes 30 are implanted within soft tissue, such as musculature, proximate to medial branches of one or both hypoglossal nerves.
  • one or more electrodes 30 may be approximately 5 mm (e.g., 2 mm to 8 mm) from a major trunk of the hypoglossal nerve.
  • one or more electrodes 30 may be placed in an area of protrusor muscles 42 and 46 that include motor points, where each nerve axon terminates in the muscle (also called the neuro-muscular junction). The motor points are not at one location but spread out in the protrusor muscles.
  • Leads 20 may be implanted such that one or more electrodes 30 may be generally in the area of the motor points (e.g., such that the motor points are within 1 to 10 mm from one or more electrodes 30).
  • Tongue 40 includes a distal end (e.g., tip of tongue 40), and electrodes 30 may be implanted proximate to root 49 of tongue 40.
  • the surgeon may implant one or more leads 20 such that one or more electrodes are implanted proximate to root 49 of tongue 40, as illustrated in FIG. 1.
  • the location for stimulation for the genioglossus muscle 42 may be approximately 30 mm (e.g., 25 mm to 35 mm) from the symphysis of the jaw (e.g., where the genioglossus and hypoglossal muscles insert).
  • the location for stimulation for the geniohyoid muscle 46 may be approximately 40 mm (e.g., 35 mm to 45 mm) from the symphysis.
  • the location for stimulation may be approximately 11 mm (e.g., 7 mm to 15 mm) lateral to the midline on both the right and left sides of tongue 40 for stimulating respective hypoglossal nerves.
  • the examples described in this disclosure may be configured for stimulating the motor points.
  • Stimulating the motor points may result in indirect activation of the hypoglossal nerve, but may generally be stimulating at a different location than direct stimulation to the hypoglossal nerve.
  • simulation of one or more motor points may result in more precise activation of muscle fibers than may be possible with stimulation of the hypoglossal nerve itself.
  • stimulating the hypoglossal nerves which includes examples of stimulating the motor end point.
  • One or more electrodes 30 of lead 20 may be ring electrodes, segmented electrodes, partial ring electrodes or any suitable electrode configuration. Ring electrodes extend 360 degrees around the circumference of the lead body of lead 20. Segmented and partial ring electrodes each extend along an arc less than 360 degrees (e.g., 90-120 degrees) around the outer circumference of the lead body of lead 20. In this manner, multiple segmented electrodes may be disposed around the perimeter of lead 20 at the same axial position of the lead. In some examples, segmented electrodes may be useful for targeting different fibers of the same or different nerves at respective circumferential positions with respect to the lead to generate different physiological effects (e.g., therapeutic effects), permitting stimulation to be oriented directionally.
  • physiological effects e.g., therapeutic effects
  • lead 20 may be, at least in part, paddle-shaped (e.g., a “paddle” lead), and may include an array of electrodes arranged as contacts or pads on a common surface, which may or may not be substantially flat and planar.
  • electrodes 30 are within musculature of tongue 40. Accordingly, one or more electrodes 30 may be “intramuscular electrodes.” Intramuscular electrodes may be different than other electrodes that are placed on or along a nerve trunk or branch, such as a cuff electrode, used to directly stimulate the nerve trunk or branch.
  • the cuff, with the cuff electrodes includes the cuff electrodes on one side of the cuff (e.g., the side that wraps around the nerve). In one or more examples, the other side of the cuff may include one or more electrodes configured to sense the EMG signals and/or CMAP signals.
  • the side of the cuff that includes the electrodes for stimulation may also include one or more electrodes for sensing EMG signals and/or CMAP signals.
  • one or more electrodes may function as stimulation electrodes as well as sensing electrodes.
  • the example techniques described in this disclosure are not limited to intramuscular electrodes and may be extendable to electrodes placed closer to a nerve trunk or branch of the hypoglossal nerve(s).
  • one or more electrodes 30 may be implanted in connective tissue or other soft tissue proximate to the hypoglossal nerve.
  • lead 20 may be configured for advancement through the soft tissue, which may include the protrusor muscle tissue, to anchor electrodes 30 in proximity to the hypoglossal nerve(s) that innervate protrusor muscles 42 and/or 46 and/or motor points that connect axons of hypoglossal nerve(s) to respective muscle fibers of protrusor muscles 42 and/or 46.
  • lead 20 may be configured for advancement through vasculature of tongue 40.
  • a surgeon may implant lead 20 in the lingual veins near the hypoglossal nerve though venous access in the subclavian vein.
  • one or more electrodes 30 may be “intravascular electrodes.”
  • electrical stimulation therapy generated by IMD 16 and delivered via one or more electrodes 30 may activate protrusor muscles 42 and 46 to move tongue 40 forward, for instance, to promote a reduction in obstruction or narrowing of the upper airway 48 during sleep.
  • protrusor muscles 42 and 46 refers to electrical stimulation that causes depolarization or an action potential of the cells of the nerve (e.g., hypoglossal nerve(s)) or stimulation at the neuro-muscular junction between the nerve and the protrusor muscles (e.g., at the motor points) innervating protrusor muscles 42 and 46 and motor points and subsequent depolarization and mechanical contraction of the protrusor muscle cells of protrusor muscles 42 and 46.
  • protrusor muscles 42 and 46 may be activated and advanced directly by the electrical stimulation therapy.
  • Protrusor muscles 42 and/or 46, on a first side of tongue 40 may be activated by a medial branch of a first hypoglossal nerve
  • the protrusor muscles, on a second side of tongue 40 may be activated by a medial branch of a second hypoglossal nerve.
  • the medial branch of a hypoglossal nerve may also be referred to as the Xllth cranial nerve.
  • the hyoglossus and styloglossus muscles (not shown in FIG. 1), which cause retraction and elevation of tongue 40, are activated by a lateral branch of the hypoglossal nerve.
  • One or more electrodes 30 may be used to deliver bilateral or unilateral stimulation to protrusor muscles 42 and 46 via the medial branch of the hypoglossal nerve or branches of the hypoglossal nerve (e.g., such as at the motor point where a terminal branch of the hypoglossal nerve interfaces with respective muscle fibers of protrusor muscles 42 and/or 46).
  • one or more electrodes 30 may be coupled to output circuitry of IMD 16 to enable delivery of electrical stimulation pulses in a manner that selectively activates the right and left protrusor muscles (e.g., in a periodic, cyclical or alternating pattern) to avoid muscle fatigue while maintaining upper airway patency.
  • IMD 16 may deliver electrical stimulation to selectively activate protrusor muscles 42 and/or 46 or portions of protrusor muscles 42 and/or 46 during unilateral stimulation of the left or right protrusor muscles.
  • one lead 20 may be implanted such that one or more of electrodes 30 deliver electrical stimulation to stimulate the left hypoglossal nerve (e.g., including examples of stimulating motor points) of protrusor muscles on the left side of tongue, and therefore cause the left protrusor muscles to activate.
  • the electrical stimulation from one or more electrodes 30 may not be of sufficient amplitude to stimulate the right hypoglossal nerve (e.g., or motor points) of protrusor muscles on the right side of tongue and cause the right protrusor muscles to activate.
  • one lead 20 may be implanted such that one or more of electrodes 30 deliver electrical stimulation to stimulate the right hypoglossal nerve (e.g., including examples of stimulating motor points) of protrusor muscles on the right side of tongue, and therefore cause the right protrusor muscles to activate.
  • the electrical stimulation from one or more electrodes 30 may not be of sufficient amplitude to stimulate the left hypoglossal nerve (e.g., or motor points) of protrusor muscles on the left side of tongue and cause the left protrusor muscles to activate.
  • two leads like lead 20 may be implanted to stimulate each of the left and right hypoglossal nerves and/or motor points of respective protrusor muscles on the left and right side of tongue 40.
  • An example of the two leads being implanted for stimulating the left and right side of tongue 40 is illustrated in FIG. 2.
  • IMD 16 may stimulate one hypoglossal nerve or one set of motor points and then the other hypoglossal nerve or another set of motor points, which can reduce muscle fatigue.
  • continuous stimulation may cause protrusor muscles to be continuously in an activated/advanced state. This continuous contraction may cause protrusor muscles 42 and/or 46 to fatigue.
  • the stimulation may not cause protrusor muscles 42 and/or 46 to maintain an activated/advanced state (or higher intensity of the electrical stimulation may be needed to cause protrusor muscles 42 and/or 46 to remain in the activated/advanced state).
  • a second set e.g., other of left or right
  • Stimulation may then alternate to stimulate the protrusor muscles that were at rest and thereby maintain protrusion of tongue 40, while permitting the protrusor muscles 42 and/or 46 that were previously activated to rest.
  • tongue 40 can remain in the activated/advanced state, while one of the first or second set of protrusor muscles is at rest.
  • both the right and the left side of tongue 40 may be stimulated for at least a portion of the time.
  • one or more of electrodes 30 or 31 may be configured to sense one or more signals received from tissue of patient 14.
  • the one or more signals received from the patient tissue may include one or more of a compound muscle action potential (CMAP) or an electromyography (EMG) signal.
  • CMAP signals may be evoked, in that, CMAP signals may be generated in muscles in response to (e.g., caused by) delivery of electrical stimulation.
  • An evoked CMAP signal may be considered as including two components: an artifact component and non-artifact component (e.g., true CMAP signal component).
  • Electromyography (EMG) signals may be considered as a different class of signals generated in muscles than CMAP signals.
  • EMG signals may be intrinsic signals that are not evoked by delivery of electrical stimulation, and are present regardless of whether there is delivery of electrical stimulation.
  • the CMAP and/or EMG signals may be indicative of movement the tongue.
  • processing circuitry of IMD 16 may be configured to receive, via one or more of electrodes 30 and/or 31, one or more signals from patient tissue of patient 14, determine whether the one or more signals from the patient tissue are indicative of volitional movement of a tongue of patient 14, and control therapy of IMD 16 to deliver therapy for sleep apnea based on the determination.
  • the one or more signals may be indicative of volitional movement of the tongue.
  • the processing circuitry may automatically turn IMD 16 to an OFF, SNOOZE, or DELAY therapy state. Automatically turning IMD 16 to an OFF, SNOOZE, or DELAY therapy state may conserve battery life of IMD 16 and reduce discomfort of the patient. Furthermore, in this example, the processing circuitry of IMD 16 may determine that one or more volitional movements of the tongue correspond to control inputs from the patient to turn IMD 16 to an ON, OFF, SNOOZE, DELAY, CALIBRATE, or other state. By allowing the patient to control a therapy state of IMD 16 using volitional tongue movements, the patient may adjust therapy provided by IMD 16 without relying on an external device.
  • the one or more signals may be indicative of non-volitional movement of the tongue.
  • the processing circuitry may turn IMD 16 to an ON therapy state, or maintain IMD 16 in the ON therapy state.
  • no tongue movement is an example of determination of whether the one or more signals are indicative of volitional movement.
  • the one or more signals may be indicative of no movement of the tongue.
  • the processing circuitry may turn IMD 16 to an ON therapy state or maintain IMD 16 in the ON therapy state.
  • FIG. 2 is a conceptual diagram illustrating an example location of lead implantation for stimulation for OSA therapy and sensing of one or more signals in tissue of the patient.
  • the one or more sensed signals include compound muscle action potential (CMAP) signals and/or electromyography (EMG) signals.
  • CMAP compound muscle action potential
  • EMG electromyography
  • FIG. 2 illustrates lead 20 and lead 21 implanted in tongue 40 on each side of medial line 33. That is, lead 20 may be considered to sense signals from and stimulate patient tissue on the left side of tongue 40, and lead 21 may be considered to sense signals from and stimulate patient tissue on the right side of tongue 40.
  • electrodes 30 and/or 32 may receive one or more signals from patient tissue.
  • one or more of electrodes 30 and/or 32 may sense a CMAP signal or EMG signal from patient tissue.
  • Processing circuitry of IMD 16 may control therapy of IMD 16 to deliver OSA therapy to patient 14 by stimulating patient tissue via one or more of electrodes 30 and/or 32.
  • the processing circuitry of IMD 16 may utilize the sensed signals (e.g., sensed from electrodes 30 and/or 32) to determine whether patient 14 has volitional control over the tongue, and control therapy based on the determination.
  • lead 20 includes one or more electrodes 30, and lead 21 includes one or more electrodes 32.
  • IMD 16 may be configured to deliver a therapeutic electrical stimulation signal through one or more of electrodes 30 to stimulate the left part of tongue 40 to activate the protrusor muscles on the left side of tongue 40, and advance tongue 40. Then, IMD 16 may be configured to deliver a therapeutic electrical stimulation signal through one or more of electrodes 30 to stimulate the right part of tongue 40 to activate the protrusor muscles on the right side of tongue 40, and advance tongue 40.
  • IMD 16 may alternate delivery of therapy between left and right sides of tongue 40, which causes tongue 40 to advance, while minimizing fatigue. In some examples, IMD 16 may alternate between different sets of electrodes on the same side of tongue 40.
  • FIG. 3 is block diagram illustrating example configurations of implantable medical devices (IMDs) which may be utilized in the system of FIG. 1.
  • IMD 16 includes sensing circuitry 56, processing circuitry 57, stimulation circuitry 58, switch circuitry 59, memory 60, telemetry circuitry 61, and power source 62.
  • IMD 16 may include a greater or fewer number of components.
  • Switch circuitry 59 may be configured to, in response to instructions from processing circuitry 57, switch the coupling of electrodes 30 between sensing circuitry 56 and therapy delivery circuitry 58.
  • switch circuitry 59 may be configured to allow therapy delivery circuitry 58 to deliver electrical stimulation signal via one or more electrodes 30 of lead 20, and allow sensing circuitry 56 to sense the CMAP signal from one or more electrodes 31 of lead 22 that are generated in response to the delivery of the electrical stimulation signal.
  • switch circuitry 59 may couple therapy delivery circuitry 58 to one or more electrodes 30 of lead 20, and couple sensing circuitry 56 to one or more electrodes 31 of lead 22.
  • switch circuitry 59 may couple therapy delivery circuitry 58 to one or more electrodes 31 of lead 22, and couple sensing circuitry 56 to one or more electrodes 30 of lead 20. Switch circuitry 59 may repeat such operations. In some examples, EMG signals and CMAP signals may be sensed on the same electrodes of electrodes 30 and/or 31.
  • stimulation circuitry 58 may include a plurality of regulated current sources or sinks, with each current source or sink coupled to one of electrodes 30 or 31. In such examples, stimulation circuitry 58 may control each current source or sink and switching between electrodes 30 and 31 may not be necessary for therapy delivery since each one of electrodes 30 and 31 is individually controllable.
  • Stimulation circuitry 58 may deliver electrical stimulation according to stimulation parameters stored in memory 60.
  • stimulation circuitry 58 delivers electrical stimulation in the form of electrical pulses.
  • relevant stimulation parameters may include a voltage or current pulse amplitude, a pulse rate, a pulse width, a duty cycle, and/or the combination of electrodes 30 that stimulation circuitry 58 uses to deliver the stimulation signal.
  • stimulation circuitry 58 delivers electrical stimulation in the form of continuous waveforms.
  • relevant stimulation parameters may include a voltage or current amplitude, a frequency, a shape of the stimulation signal, a duty cycle of the stimulation signal, or the combination of electrodes 30 and 32 of stimulation circuitry 58 uses to deliver the stimulation signal.
  • the stimulation parameters for the stimulation programs 63 may be selected to cause protrusor muscles 42 and/or 46 to an activated/advanced state (e.g., to open-up airway 48).
  • IMD 16 may include one or more sensors configured to sense posture or position of patient 14.
  • IMD 16 may include accelerometer to determine if patient 14 is lying down, whether lying on a back, whether lying on a side, and generally posture of patient 14.
  • Another example of the one or more sensors is a motion sensor, and movement sensed by the motion sensor may indicate if patient 14 is having restless sleep, which may be indicative of the onset of OSA.
  • Additional examples of the sensors include acoustical sensors or a microphone for detecting vibrations in upper airway 48. Vibrations in upper airway 48 may be indicative of the onset of OSA.
  • processing circuity 57 may control delivery of therapy based on information received from the one or more sensors, such as delivery of therapy after sensing an onset of OSA.
  • IMD 16 may include or be in communication with one or more sensors configured to sense other physiological parameters of patient 14.
  • a system including the IMD may also include a heart rate monitor, a continuous glucose monitor, and/or any other sensor to sense physiological data of patient 14.
  • IMD 16 may determine, based on a heart rate of patient 14, that patient 14 is likely to be asleep (e.g., heart rate is below a threshold rate). IMD 16 may further determine, in response to determining that patient 14 is likely to be asleep based on their heart rate, that the one or more signals received from patient tissue are not indicative of volitional movement of the tongue of the patient.
  • electrodes 30 and 31 may be configured to sense electromyography (EMG) signals.
  • Sensing circuitry 56 may be coupled to electrodes 30 and 31 via switch circuitry 59 to be used as EMG sensing electrodes when electrodes 30 and 31 are not being used for stimulation.
  • switch circuitry 59 to be used as EMG sensing electrodes when electrodes 30 and 31 are not being used for stimulation.
  • there may be other electrodes or sensors used to sense EMG signals.
  • IMD 16 may comprise any suitable arrangement of hardware, alone or in combination with software and/or firmware, to perform the techniques attributed to IMD 16 and sensing circuitry 56, processing circuitry 57, stimulation circuitry 58, and telemetry circuitry 61 of IMD 16.
  • IMD 16 may include one or more processors, such as one or more microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or any other equivalent integrated or discrete logic circuitry, as well as any combinations of such components.
  • DSPs digital signal processors
  • ASICs application specific integrated circuits
  • FPGAs field programmable gate arrays
  • the various units of IMD 16, such as processing circuitry 57, may be implemented as fixed-function circuits, programmable circuits, or a combination thereof.
  • Fixed-function circuits refer to circuits that provide particular functionality, and are preset on the operations that can be performed.
  • Programmable circuits refer to circuits that can be programmed to perform various tasks, and provide flexible functionality in the operations that can be performed.
  • programmable circuits may execute software or firmware that cause the programmable circuits to operate in the manner defined by instructions of the software or firmware.
  • Fixed-function circuits may execute software instructions (e.g., to receive parameters or output parameters), but the types of operations that the fixed-function circuits perform are generally immutable.
  • one or more of the units may be distinct circuit blocks (fixed-function or programmable), and in some examples, one or more of the units may be integrated circuits.
  • IMD 16 may include arithmetic logic units (ALUs), elementary function units (EFUs), digital circuits, analog circuits, and/or programmable cores, formed from programmable circuits.
  • ALUs arithmetic logic units
  • EFUs elementary function units
  • memory 60 may store the instructions (e.g., object code) of the software that processing circuitry 57 receives and executes, or another memory within IMD 16 (not shown) may store such instructions.
  • IMD 16 also, in various examples, may include a memory 60, such as random access memory (RAM), read only memory (ROM), programmable read only memory (PROM), erasable programmable read only memory (EPROM), electronically erasable programmable read only memory (EEPROM), flash memory, comprising executable instructions for causing the one or more processors to perform the actions attributed to them.
  • a memory 60 such as random access memory (RAM), read only memory (ROM), programmable read only memory (PROM), erasable programmable read only memory (EPROM), electronically erasable programmable read only memory (EEPROM), flash memory, comprising executable instructions for causing the one or more processors to perform the actions attributed to them.
  • sensing circuitry 56, processing circuitry 57, stimulation circuitry 58, switch circuitry 59, and telemetry circuitry 61 are described as separate circuitry, in some examples, sensing circuitry 56, processing circuitry 57, stimulation circuitry 58, switch circuitry 59, and telemetry circuit
  • Memory 60 stores therapy state programs 63 and signal database 64.
  • Therapy state programs 63 may include instructions for execution by processing circuitry 57 to control therapy states of IMD 16.
  • Signal database 64 may include one or more sets of signal data indicative of signals from patient tissue.
  • Memory 60 may also store programs that specify stimulation parameter values for the electrical stimulation provided by IMD 16.
  • Information related to sensed parameters of patient 14 e.g., from sensing circuitry 56 or the one or more sensors of IMD 16
  • Memory 60 may also store instructions for execution by processing circuitry 57, in addition to therapy state programs 63.
  • memory 60 includes separate memories for storing instructions, electrical signal information, and therapy state programs 63.
  • memory 60 and processing circuitry 57 are shown in FIG. 3 as part of IMD 16, in some examples, memory 60 and processing circuitry 57 may be included, in whole or in part, as part of other computing devices in a system that includes IMD 16 (e.g., system 10 of FIG. 1). For example, functions or actions attributed to memory 60 and processing circuitry 57 of IMD 16 may also be performed, in whole or in part, by a memory and processing circuitry of an external device (e.g., memory 74 and processing circuitry 72 of external device 70 shown in FIG. 4). Telemetry circuitry (e.g., telemetry circuitry 61) of different computing devices in the system may allow data transfer between the devices so that functions or actions of the disclosure may be performed by any combination of computing devices in the system.
  • Telemetry circuitry e.g., telemetry circuitry 61
  • stimulation circuitry 58 generates and delivers electrical stimulation under the control of processing circuitry 57.
  • processing circuitry 57 controls stimulation circuitry 58 by accessing memory 60 to selectively access and load at least one of therapy state programs 63 to stimulation circuitry 58.
  • processing circuitry 57 may access memory 60 to load one of therapy state programs 63 to control stimulation circuitry 58 for delivering the electrical stimulation to patient 14.
  • a clinician or patient 14 may select a particular therapy state for IMD 16 using an external device, such as a patient programmer, or clinician programmer, or other external device (e.g., a smartphone).
  • Processing circuitry 57 may receive the selection via telemetry circuitry 61.
  • processing circuitry 57 may load one or more of therapy state programs 63 to control therapy of IMD 16.
  • processing circuitry 57 may receive an instruction from an external device to change the therapy state of IMD 16 to an ON therapy state.
  • processing circuitry 57 may change the therapy state of IMD 16 to a DELAY therapy state.
  • processing circuitry 57 may load one or more of therapy state programs 63 to control therapy of IMD 16 in response to receiving one or more signals from patient tissue.
  • processing circuitry 57 may determine that the one or more signals correspond to a volitional tongue movement from patient 14 indicating a desired change in therapy state, and processing circuitry 57 may load the one or more therapy state programs 63 corresponding to the desired change.
  • processing circuitry 57 may control stimulation circuitry 58 to deliver or terminate the electrical stimulation based on patient input received via telemetry circuitry 61.
  • Telemetry circuitry 61 includes any suitable hardware, firmware, software or any combination thereof for communicating with another device, such as an external device. Under the control of processing circuitry 57, telemetry circuitry 61 may receive downlink telemetry (e.g., patient input) from and send uplink telemetry (e.g., therapy state status) to a programmer with the aid of an antenna, which may be internal and/or external. Processing circuitry 57 may provide the data to be uplinked to the programmer and the control signals for telemetry circuitry 61 and receive data from telemetry circuitry 61. Generally, processing circuitry 57 controls telemetry circuitry 61 to exchange information with devices external to IMD 16. Also, in some examples, IMD 16 may communicate with other implanted devices, such as stimulators, control devices, or sensors, via telemetry circuitry 61.
  • IMD 16 may communicate with other implanted devices, such as stimulators, control devices, or sensors, via telemetry circuitry 61.
  • description of IMD 16 performing an action implies the use of circuitry of IMD 16 to perform that action.
  • description of IMD 16 receiving one or more signals from patient tissue may be understood as sensing circuitry 56 receiving the one or more signals from one or more electrodes.
  • description of IMD 16 determining whether the one or more signals are indicative of volitional movement of a tongue of the patient may be understood as processing circuitry 57 making the determination based on instructions read from memory 60.
  • Power source 62 delivers operating power to the components of IMD 16.
  • Power source 62 may include a battery and a power generation circuit to produce the operating power.
  • the battery may be rechargeable to allow extended operation. Recharging may be accomplished through proximal inductive interaction between an external charger and an inductive charging coil within IMD 16.
  • an external inductive power supply may transcutaneously power IMD 16 whenever electrical stimulation is to occur.
  • Processing circuitry 57 of IMD 16 may alter a therapy state of IMD 16 in response to measurement of patient physiological parameters. In this way, IMD 16 may ensure that OSA therapy is provided to the patient when therapy is needed, and not provided when therapy may interfere with the patient’s volitional control of the patient’s tongue.
  • the physiological parameters include one or more signals sensed from patient tissue.
  • processing circuitry 57 may be configured to receive, via sensing circuitry 56 electrically connected to one or more electrodes in close proximity to one or more of a hypoglossal nerve and protrusor muscle of the patient, one or more signals from patient tissue.
  • the one or more signals received may include one or more of EMG signals and/or CMAP signals indicative of patient tongue motion.
  • CMAP signals may be evoked, in that, CMAP signals may be generated in muscles in response to (e.g., caused by) delivery of electrical stimulation.
  • processing circuitry 57 may be configured to deliver, via stimulation circuitry 56, one or more electrical stimulation pulses to the patient tissue, and sense, via the one or more electrodes, one or more CMAP signals from the patient tissue evoked in response to the delivery of the one or more electrical stimulation pulses.
  • EMG signals are biomedical signals that reflect electrical currents generated in muscles during muscle contraction, representing neuromuscular activities. Therefore, EMG signals need not be evoked.
  • Processing circuitry 57 may further be configured to determine whether the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient. In one instance, processing circuitry 57 may determine that the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient. In another instance, processing circuitry 57 may determine that the one or more signals from the patient tissue are not indicative of volitional movement of the tongue of the patient. In some examples where processing circuitry 57 determines that the one or more signals are not indicative of volitional movement of the tongue, processing circuitry 57 may determine that the one or more signals are indicative of non-volitional movement of the tongue (e.g., from delivery of OSA therapy). In some examples where processing circuitry 57 determines that the one or more signals are not indicative of volitional movement of the tongue, processing circuitry 57 may determine that the one or more signals don’t satisfy a threshold likeliness of being indicative of volitional tongue movement.
  • processing circuitry 57 may be configured to compare the one or more signals to one or more sets of reference signal data stored in a database in memory.
  • the reference signal data may be known to correspond to volitional movement.
  • the reference signal data may be known to correspond to nonvolitional movement (e.g., movement evoked by stimulation/OSA therapy).
  • the one or more sets of reference signal data may be stored in signal database 64.
  • the one or more sets of reference signal data may be stored in memory of a different computing device of the system that includes IMD 16, with which IMD 16 is in communication (e.g., via telemetry circuitry 61).
  • the reference signal data may be known to correspond to volitional movement used as a control input to control a therapy state of IMD 16.
  • one or more sets of reference signal data correspond to population averages of signal data from tongue movements from a plurality of patients.
  • one or more sets of reference signal data known to correspond to volitional tongue movement may be calculated from population averages of signal data from volitional tongue movements from a plurality of patients.
  • one or more sets of reference signal data known to correspond to non-volitional tongue movement may be calculated from population averages of signal data from non-volitional tongue movements from a plurality of patients.
  • the one or more sets of reference signal data (e.g., either volitional or nonvolitional) may reflect signal patterns corresponding specifically to tongue movement of the patient from which the one or more signals were received.
  • IMD 16 may collect one or more sets of reference signal data corresponding to volitional tongue movements.
  • the patient may perform one or more volitional tongue motions, and the one or more signals received from the patient’s tongue during the motions may be stored in signal database 64 as associated with the patient, where each of the one or more signals is associated with one or more of the volitional tongue motions.
  • IMD 16 may store volitional tongue motions in signal database 64 as control inputs for patient to control a therapy state of IMD 16.
  • IMD 16 may store one or more signals corresponding to a hard swallow as a control input to turn IMD 16 to an OFF therapy state.
  • processing circuitry 57 may utilize machine learning based techniques.
  • therapy state programs 63 (or another device in communication with IMD 16) may include a machine learning program.
  • Processing circuitry 57 (or processing circuitry of another device in communication with IMD 16) may receive the reference signal data known to correspond to volitional movement of the tongue. Using the reference signal data, processing circuitry 57 may train a neural network to generate a trained neural network that identifies whether a sensed signal corresponds to volitional movement or not.
  • IMD 16 or another device like a programmer may store the trained neural network (e.g., as part of therapy state programs 63).
  • the input to the trained neural network may be the sensed signal, and the output from the trained neural network may be information indicative of whether the one or more signals, from the patient tissue, are indicative of volitional movement of the tongue of the patient.
  • processing circuitry 57 may determine that the one or more signals from patient tissue are indicative of volitional tongue movement. In some examples, if the one or more signals from the patient tissue do not satisfy a threshold similarity with the one or more sets of reference signal data corresponding to volitional movement, processing circuitry 57 may determine that the one or more signals from patient tissue are not indicative of volitional tongue movement. If the one or more signals from the patient tissue satisfy a threshold similarity with the one or more sets of reference signal data corresponding to nonvolitional movement, processing circuitry 57 may determine that the one or more signals from patient tissue are not indicative of volitional tongue movement.
  • Processing circuitry 57 may further determine that the one or more signals from patient tissue are indicative of nonvolitional movement.
  • processing circuitry 57 may be configured to receive a first set of one or more signals from the patient tissue and a second set of one or more signals from the patient tissue. If processing circuitry 57 receives the second set of one or more signals from the patient tissue within a threshold amount of time after receiving the first set of one or more signals, processing circuitry 57 may determine that the first and/or second sets of signals are indicative of volitional movement of the patient’s tongue. For example, processing circuitry 57 may receive a second set of one or more signals from the patient tissue within thirty seconds of receiving a first set of one or more signals from the patient tissue. Processing circuitry 57 may determine that thirty seconds satisfies the threshold amount of time.
  • processing circuitry 57 may determine whether the one or more signals from patient tissue are indicative of volitional tongue movement of the patient based on receiving a threshold number of sets of one or more signals all within a threshold amount of time, and/or wherein each consecutively received set of one or more signals is received within a threshold amount of time from the previous set. For example, processing circuitry 57 may receive a first set of one or more signals from patient tissue, a second set, and a third set. Processing circuitry 57 may receive the second set thirty seconds after the first set, and may receive the third set forty seconds after the second set. A set number threshold stored in memory may be three sets. A time period threshold stored in memory may be five minutes. In some examples, the time period threshold may be any amount of time.
  • An interval time threshold stored in memory may be sixty seconds. In some examples, an interval time threshold may be more or less than sixty seconds.
  • Processing circuitry 57 may determine that the three sets satisfies the set number threshold. Processing circuitry 57 may determine that the three sets of one or more signals were all received within a time period of seventy seconds, and may determine that the time period of seventy seconds satisfies the time period threshold. Processing circuitry 57 may determine that each interval between sets (thirty seconds and forty seconds) satisfies the interval time threshold.
  • processing circuitry 57 may determine that the first, second, and/or third sets of one or more signals are indicative of volitional tongue movement of the patient. In some examples, processing circuitry 57 may determine that the sets of one or more signals are indicative of volitional tongue movement based only on satisfaction of the interval time threshold.
  • processing circuitry 57 may be configured to determine a time of day corresponding to the one or more signals (e.g., the time of day at which the one or more signals were received). For example, processing circuitry 57 may receive the time of day from an internal clock of IMD 16. In some examples processing circuitry 57 may receive the time of day from an external device in communication with IMD 16 via telemetry circuitry 61.
  • Processing circuitry 57 may determine that the one or more signals from patient tissue are indicative of volitional tongue movement of the patient if the time of day is within a first interval, and processing circuitry 57 may determine that the one or more signals are not indicative of volitional tongue movement of the patient if the time of day is within a second interval.
  • a first interval may be 11AM to 3PM, and processing circuitry 57 may receive the one or more signals at 12: 10PM.
  • Processing circuitry 57 may determine that 12: 10 PM is within the first interval and that the one or more signals are indicative of volitional tongue movement.
  • a second interval may be 1AM to 3AM, and processing circuitry 57 may receive the one or more signals at 1:30AM.
  • Processing circuitry 57 may determine that 1:30AM is within the second interval and that the one or more signals are not indicative of volitional tongue movement.
  • processing circuitry 57 may be configured to determine one or more movements of the patient corresponding to the one or more signals (e.g., one or more movements of the patient at or near the time the one or more signals were received).
  • IMD 16 or another device in communication with IMD 16 may include one or more accelerometers to track patient movement (e.g., walking, breathing, etc.).
  • processing circuitry 57 may determine, based on pedometer or other accelerometer signals, that the patient is walking, running, jumping, etc.
  • processing circuitry 57 may determine that the one or more signals are indicative of volitional tongue movement. In some examples, processing circuitry 57 may determine that a breathing rate of the patient exceeds a threshold breathing rate. In response to determining that the breathing rate of the patient exceeds a threshold breathing rate, processing circuitry 57 may determine that the one or more signals are indicative of volitional tongue movement.
  • processing circuitry 57 may be configured to determine a heart rate of the patient at or near the time the one or more signals were received.
  • IMD 16 or another device in communication with IMD 16 may include a heart rate monitor.
  • Processing circuitry 57 may determine that relatively high measured heart rates indicate that the patient is awake, and therefore not in need of OSA therapy, and may also determine that relatively low measure heart rates indicate that the patient is asleep, and may need OSA therapy.
  • processing circuitry 57 may determine that, if the measured heart rate of the patient exceeds a heart rate threshold, the one or more signals are indicative of volitional patient movement.
  • a heart rate threshold may be 100 beats per minute (bpm), and the measured heart rate may be 120 bpm.
  • Processing circuitry 57 may determine that 120 bpm exceeds the heart rate threshold and that the one or more signals received from patient tissue at or near the time of the measured heart rate are indicative of volitional tongue movement.
  • processing circuitry 57 may determine that, if the measured heart rate of the patient satisfies a lower threshold, the one or more signals are indicative of nonvolitional patient movement.
  • a lower heart rate threshold may be 48 bpm, and the measured heart rate may be 45 bpm.
  • Processing circuitry 57 may determine that 45 bpm satisfies the lower heart rate threshold, and that the one or more signals received from patient tissue at or near the time of the measured heart rate are indicative of nonvolitional tongue movement.
  • processing circuitry 57 may determine whether signals from patient tissue are indicative of volitional movement of the tongue with greater certainty. Processing circuitry 57 may analyze the time of day, posture, heart rate, and other physiological parameters to confirm determinations made by processing circuitry 57 based on the signals received from patient tissue.
  • processing circuitry 57 may be configured to deliver, via stimulation circuitry 58 of IMD 16, one or more electrical stimulation pulses to the patient tissue. Electrical stimulation may evoke CMAP signals generated in muscles in response to (e.g., caused by) delivery of the electrical stimulation.
  • IMD 16 may be in an ON therapy state, in which processing circuitry 57 is configured to provide OSA therapy to the tongue of the patient by causing the stimulation circuitry to deliver a therapeutic stimulation signal to patient tissue.
  • Processing circuitry 57 may sense, via one or more electrodes, the one or more signals as one or more evoked signals from the patient tissue evoked in response to the delivery of the one or more electrical stimulation pulses. Processing circuitry 57 may receive the one or more signals within a threshold amount of time after delivering the one or more electrical stimulation pulses, and in response, determine that the one or more signals are not indicative of volitional tongue movement. For example, processing circuitry 57 may receive the one or more signals within 10 ms of delivering the stimulation pulses, and may determine that the one or more signals are not indicative of volitional tongue movement. In some examples, the threshold amount of time may differ depending on the stimulation rate at which IMD 16 provides OSA therapy.
  • processing circuitry 57 may receive a plurality of sets of signals from patient tissue, where each set of the plurality of sets of signals is received at regular intervals, and each set of the plurality of sets of signals is received shortly after delivery of the one or more electrical stimulation pulses. In response, processing circuitry 57 may determine that the plurality of sets of signals are indicative of nonvolitional movement of the tongue of the patient.
  • IMD 16 may be in an ON therapy state, in which processing circuitry 57 is configured to provide OSA therapy to the tongue of the patient by causing the stimulation circuitry to deliver one or more electrical stimulation pulses at regular intervals to patient tissue.
  • the one or more electrical stimulation pulses at regular intervals may cause regular CMAP signals to be generated in response to the stimulation pulses.
  • processing circuitry 57 may be configured to pause delivery of the one or more electrical stimulation pulses. For example, processing circuitry 57 may pause delivery for a length of time or a number of stimulation pulses. In some examples, processing circuitry 57 may pause delivery of the one or more electrical stimulation pulses for five seconds. In some examples, processing circuitry 57 may not deliver the next five stimulation pulses.
  • processing circuitry 57 may sense for a second set of one or more signals from the patient tissue. Because stimulation has been paused, received signals may not be evoked CMAP signals, although a first signal during the pause may be a CMAP signal received in response to the previous electrical stimulation pulse. Processing circuitry 57 may receive a second set of one or more signals during the pause, and in response, determine that the first and/or second set of one or more signals are indicative of volitional tongue movement. In some examples, processing circuitry 57 may not receive a second set of one or more signals during the pause, and in response, determine that the first set of one or more signals are not indicative of volitional tongue movement.
  • processing circuitry 57 may use any combination of methods to determine whether the one or more signals from the patient tissue are indicative of volitional movement of a tongue of the patient. For example, processing circuitry 57 may determine that the one or more signals from the patient tissue do not satisfy a threshold similarity with one or more sets of reference signal data in memory corresponding to volitional movement, however, processing circuitry 57 may receive ten sets of such one or more signals from patient tissue that do not satisfy the threshold within a short time period (e.g., 5 minutes), and processing circuitry 57 may determine that the time of day is between 12PM and 1PM. Based on this combination, processing circuitry 57 may determine that the one or more signals from patient tissue are indicative of volitional movement of the tongue of the patient, despite the one or more signals not satisfying the threshold similarity with reference signal data.
  • a short time period e.g., 5 minutes
  • processing circuitry 57 may determine that - for a threshold number of methods for determining whether the one or more signals are indicative of voluntary tongue movement - processing circuitry 57 determined that the one or more signals are indicative of volitional tongue movement.
  • a method threshold may be 70% of methods used must indicate that the one or more signals are indicative of volitional tongue movement. If, for only one out of four methods used, processing circuitry 57 determines that the one or more signals are indicative of volitional tongue movement, processing circuitry 57 may determine that the method threshold has not been satisfied and may determine that the one or more signals are not indicative of volitional tongue movement.
  • processing circuitry 57 may control therapy of IMD 16, wherein IMD 16 is configured to deliver therapy for sleep apnea.
  • processing circuitry of the IMD may be configured to automatically change a therapy state of the IMD to an appropriate therapy state with, without, and/or despite patient input.
  • the IMD may interpret volitional movements of the tongue by the patient as instructions to change the therapy state.
  • Therapy state programs 63 may include instructions for execution by processing circuitry 57 to control therapy states of IMD 16.
  • therapy state programs 63 may include instructions for when to transition between an ON therapy state, OFF therapy state, DELAY therapy state, SNOOZE therapy state, and CALIBRATION therapy state. The preceding list is non -exhaustive.
  • processing circuitry 57 in the ON therapy state, is configured to provide OSA therapy to a tongue of the patient by causing stimulation circuitry 58 to deliver therapeutic stimulation signals to patient tissue. In some examples, in the OFF therapy state, the processing circuitry 57 is configured to not deliver electrical stimulation pulses for treating sleep apnea. In some examples, in the OFF therapy state, processing circuitry 57 may still sense for signals from patient tissue via the one or more electrodes on the one or more leads attached to IMD 16.
  • IMD 16 may be in an ON therapy state, and processing circuitry 57 may determine that the one or more signals from patient tissue are indicative of volitional movement of the tongue of the patient. This may mean that, although IMD 16 has been providing OSA therapy, the patient is currently awake and not in need of OSA therapy. For example, the patient may have accidentally started a therapy program through interaction with an external device (e.g., a smartphone) in communication with IMD 16. For example, while fishing around in their pockets for a stick of gum, the patient may accidentally click a series of buttons to send an instruction to IMD 16 to enter an ON therapy state. In some examples, the patient may have been asleep and benefitting from OSA therapy, however, the patient has now awoken to use the restroom.
  • an external device e.g., a smartphone
  • processing circuitry 57 may change the therapy state of IMD 16 from the ON therapy state to an OFF therapy state. In this way, IMD 16 may allow the patient full control of their tongue while they are awake.
  • IMD 16 may be in an OFF therapy state, and processing circuitry 57 may determine that no signals indicative of volitional movement of the tongue of the patient have been received for a time period. For example, the patient may have fallen asleep without instructing IMD 16 to turn ON and provide OSA therapy. Processing circuitry 57 may change, at least partially in response to determining that no signals have been received over the time period, the therapy state of IMD 16 to an ON therapy state. For example, processing circuitry 57 may determine that no signals have been received from patient tissue for a time period of 15 minutes. In some examples the time period may be any length of time.
  • processing circuitry 57 may change the therapy state of IMD 16 to an ON therapy state.
  • processing circuitry 57 may change the therapy state of IMD 16 to an ON therapy state partially in response to determining a current time. For example, processing circuitry 57 may determine that no signals have been received from patient tissue for the time period, and that the current time is 11 :45PM. In response to both determining that no signals have been received from patient tissue for the time period and that the current time is within a nighttime time interval, processing circuitry 57 may change the therapy state of IMD 16 to an ON therapy state.
  • processing circuitry 57 may change the therapy state of IMD 16 at least partially based on other physiological parameters of the patient as well (e.g., accelerometers, heart rate, etc.). In this way, IMD 16 may provide OSA therapy to a patient even when the patient forgets to turn on the OSA therapy.
  • IMD 16 may be in an OFF therapy state, and processing circuitry may receive an instruction from an external device (e.g., a smartphone) to change a therapy state of the IMD to an ON therapy state.
  • an external device e.g., a smartphone
  • processing circuitry 57 may be configured to change, in response to receiving the instruction, the therapy state to a DELAY therapy state, wherein in the DELAY therapy state, IMD 16 may be configured to wait a period of time before transitioning into the ON therapy state to deliver OSA therapy.
  • the DELAY therapy state may occur for a period of time of fifteen minutes before IMD 16 automatically transitions to the ON therapy state. This delay may allow the patient to fall asleep before IMD 16 provides OSA therapy.
  • IMD 16 may be in a therapy state that is neither OFF nor ON when IMD 16 receives the instruction to change the therapy state to an ON therapy state. Processing circuitry 57 may change whatever the current therapy state is to the DELAY therapy state.
  • IMD 16 may be in an ON therapy state, and processing circuitry 57 may determine that the one or more signals from patient tissue are indicative of volitional movement of the tongue of the patient.
  • a patient may temporarily awake from slumber, only to return to sleep moments later. It may be advantageous to continue to provide OSA therapy to the patient when the patient returns to sleep.
  • processing circuitry 57 may change the therapy state of IMD 16 from the ON therapy state to a DELAY therapy state.
  • IMD 16 may be configured to stop providing OSA therapy and wait a period of time before transitioning back into the ON therapy state to deliver OSA therapy.
  • the DELAY therapy state may occur for a period of time of two minutes before IMD 16 automatically transitions to the ON therapy state.
  • the period of time IMD 16 is configured to wait (the delay period) in the DELAY therapy state may differ depending on how IMD 16 transitioned to the DELAY therapy state.
  • IMD 16 may be in an OFF therapy state and processing circuitry 57 may change the therapy state of IMD 16 to a DELAY therapy state in response to receiving instructions from an external device to change the therapy state to an ON therapy state.
  • processing circuitry 57 may determine that it is unlikely that the patient is asleep, and may set a first delay period such that the delay period allows the patient to fall asleep before IMD 16 starts providing OSA therapy.
  • the first delay period set in response to entering the DELAY therapy state in this manner may be 10-15 minutes.
  • the patient may adjust the first delay period (e.g., through an app on a smartphone in communication with IMD 16).
  • IMD 16 may be in an ON therapy state and processing circuitry 57 may change the therapy state of IMD 16 to the DELAY therapy state in response to determining that one or more received signals from patient tissue are indicative of volitional movement of the patient’s tongue.
  • the patient may have only temporarily awoken from slumber, or entered a short period of light sleep, only to return to sleep moments later. It may be advantageous to continue to provide OSA therapy to the patient as soon as the patient returns to sleep.
  • Processing circuitry 57 may set a second delay period when IMD 16 enters the DELAY therapy state in this manner that is relatively short to ensure that IMD 16 continues to provide OSA therapy while the patient is sleeping.
  • the second delay period may be 1-2 minutes.
  • sleep studies performed on the patient may indicate a preferred amount of time for the second delay period, and a physician may adjust a second delay period (e.g., through an external programmer in communication with IMD 16) to best fit the patient’s sleep cycles.
  • processing circuitry 57 may set a longer delay period (first delay period) when changing IMD 16 from an OFF therapy state to an ON therapy state than the delay period (second delay period) when changing IMD 16 from an ON therapy state to a DELAY therapy state.
  • processing circuitry 57 may receive an indication that the patient may be awake. For example, processing circuitry 57 may determine that one or more signals received from the patient tissue are indicative of volitional movement. In some examples, processing circuitry 57 may receive information from an external device that the patient is interacting with the external device (e.g., playing a game on their phone). In response to receiving an indication that the patient may be awake, and while IMD 16 is in the DELAY therapy state, processing circuitry 57 may restart or extend the delay period timer.
  • processing circuitry 57 may track an amount of time that IMD 16 is in the DELAY therapy state. If IMD 16 is in the DELAY therapy state for an extended period of time, it may mean that the delay period timer has been restarted or extended many times (e.g., in response to processing circuitry 57 receiving an indication that the patient may be awake), and the patient may very likely be awake. In some examples, processing circuitry 57 may change a therapy state of IMD 16 from a DELAY therapy state to an OFF therapy state in response to determining that the amount of time that IMD 16 has been in the DELAY therapy state exceeds a threshold amount of time.
  • the threshold amount of time may be 1.5 hours, and processing circuitry may determine that IMD 16 has been in the DELAY therapy state for 1.6 hours. In response to determining that IMD 16 has been in the DELAY therapy state longer than the threshold amount of time, processing circuitry 57 may change the therapy state of IMD 16 from the DELAY therapy state to an OFF therapy state.
  • processing circuitry 57 may track a number of times that the delay period timer has been restarted or extended while IMD 16 is in the same DELAY therapy state. Even if IMD 16 has not been in the DELAY therapy state for an extended period of time, sometimes the sheer volume of indications that the patient may be awake can be sufficient to turn off OSA therapy. In some examples, processing circuitry 57 may change a therapy state of IMD 16 from a DELAY therapy state to an OFF therapy state in response to determining that the number of times the delay period timer has been restarted or extended exceeds a threshold number. For example, the threshold number may be 20 times, and processing circuitry may determine that the delay period timer has been restarted and/or extended 22 times.
  • processing circuitry 57 may change the therapy state of IMD 16 from the DELAY therapy state to an OFF therapy state.
  • processing circuitry 57 may determine when to deliver stimulation pulses to patient tissue to provide OSA therapy. For example, processing circuitry 57 may determine, based on the one or more received signals from patient tissue, that the tongue of the patient is not obstructing an airway of the patient. In response to determining that the tongue is not obstructing the airway, processing circuitry 57 may not deliver electrical stimulation pulses to patient tissue.
  • processing circuitry 57 may determine, based on the one or more received signals from patient tissue, that the tongue of the patient is obstructing an airway of the patient. In response to determining that the tongue is obstructing the airway, processing circuitry 57 may deliver electrical stimulation pulses to patient tissue (e.g., provide OSA therapy).
  • patient tissue e.g., provide OSA therapy.
  • IMD 16 may include one or more strain gauges attached to one or more of leads 20 and 21. Based on the strain gauges, IMD 16 may determine a position of the tongue of the patient.
  • the patient may be awake and IMD 16 may be configured to stop sensing for signals from patient tissue in order to conserve power in power source 62.
  • IMD 16 may receive one or more indications that the patient may be awake.
  • processing circuitry 57 may determine that one or more signals received from the patient tissue are indicative of volitional movement.
  • processing circuitry 57 may receive information from an external device that the patient is interacting with the external device (e.g., playing a game on their phone).
  • processing circuitry 57 may determine that the time of day is during daytime hours when the patient is most likely to be awake (e.g., based on a tracked history of patient activity saved to memory 60, based on population data for most active hours of the day on average). In some examples, processing circuitry may receive other indications that the patient may be awake (e.g., high heart rate, accelerometer data indicating patient is walking or running, high breathing rate, etc.). In response to receiving one or more indications that the patient may be awake, processing circuitry 57 may change a therapy state of IMD 16 to a SNOOZE therapy state. In the SNOOZE therapy state, processing circuitry 57 may be configured to stop sensing for signals from patient tissue for a period of time.
  • processing circuitry 57 may be configured to stop sensing for signals from patient tissue for an hour.
  • the SNOOZE period of time may be any period of time, and may be saved in memory 60.
  • the SNOOZE period of time may be set by an external device (e.g., by the patient with a smartphone, by a physician with an external programmer).
  • processing circuitry 57 may change the therapy state of IMD 16 to a SNOOZE therapy state in response to receiving a threshold number of indications that the patient is awake. For example, processing circuitry may receive a first set of one or more signals from the patient tissue and a second set of one or more signals from the patient tissue within a threshold time period from receiving the first set. In response to receiving the second set of one or more signals from patient tissue within the threshold amount of time, processing circuitry 57 may change the therapy state of IMD 16 to a SNOOZE therapy state.
  • processing circuitry 57 may receive a plurality of sets of one or more signals from patient tissue within a threshold amount of time and determine that each of the sets of the plurality of sets are indicative of volitional movement of a tongue of the patient. In addition, processing circuitry 57 may determine that the time of day is during high- activity daytime hours, and receive information from an external device that the patient is interacting with an external device. Based on the determined and received indications that the patient is awake, processing circuitry 57 may change the therapy state of IMD 16 to a SNOOZE therapy state. The threshold number and type of indications necessary for processing circuitry 57 to change the therapy state of IMD 16 to a SNOOZE therapy state may be saved in memory 60. The threshold number and type of indications may be set by an external device (e.g., by the patient with a smartphone, by a physician with an external programmer).
  • an external device e.g., by the patient with a smartphone, by a physician with an external programmer.
  • FIG. 4 is a block diagram illustrating an example configuration of an external device 70.
  • external device 70 may be an external programmer for an IMD. While device 70 may generally be described as a hand-held computing device, the device may be a notebook computer, a cell phone, or a workstation, for example. As illustrated in FIG. 4, external device 70 may include processing circuitry 72, memory 74, user interface 76, telemetry circuitry 78, and power source 80. In some examples, external device 70 may be a programmer configured to change stimulation or other therapy parameters of an implanted IMD (e.g., IMD 16). In some examples, external device 70 may be configured to change or set thresholds for therapy state programs of an IMD.
  • device 70 comprises any suitable arrangement of hardware, alone or in combination with software and/or firmware, to perform the techniques attributed to device 70, and processing circuitry 72, user interface 76, and telemetry module 78 of device 70.
  • processing circuitry 72 may include one or more processors, such as one or more microprocessors, DSPs, ASICs, FPGAs, or any other equivalent integrated or discrete logic circuitry, as well as any combinations of such components.
  • memory 74 include RAM, ROM, PROM, EPROM, EEPROM, flash memory, a hard disk, a CD-ROM, comprising executable instructions for causing the one or more processors to perform the actions attributed to them.
  • processing circuitry 72 and telemetry circuitry 78 are described as separate circuitry, in some examples, processing circuitry 72 and telemetry circuitry 78 are functionally integrated. In some examples, processing circuitry 72 and telemetry circuitry 78 correspond to individual hardware units, such as ASICs, DSPs, FPGAs, or other hardware units.
  • memory 74 may further include program information (e.g., therapy state programs) defining the therapy state change information, similar to those stored in memory 60 of IMD 16.
  • the therapy state programs stored in memory 74 may be downloaded into memory 60 of IMD 16.
  • User interface 76 may include a button or keypad, lights, a speaker for voice commands, a display, such as a liquid crystal (LCD), light-emitting diode (LED), or cathode ray tube (CRT).
  • a display such as a liquid crystal (LCD), light-emitting diode (LED), or cathode ray tube (CRT).
  • the display may be a touch screen.
  • processing circuitry 72 may present and receive information relating to electrical stimulation and resulting therapeutic effects via user interface 76.
  • processing circuitry 72 may receive patient input via user interface 76.
  • the input may be, for example, in the form of pressing a button on a keypad or selecting an icon from a touch screen.
  • Processing circuitry 72 may also present information to the patient in the form of alerts related to delivery of the electrical stimulation to patient 14 or a caregiver via user interface 76.
  • device 70 may additionally or alternatively include a data or network interface to another computing device, to facilitate communication with the other device, and presentation of information relating to the electrical stimulation and therapeutic effects after termination of the electrical stimulation via the other device.
  • Telemetry circuitry 78 supports wireless communication between IMD 16 and device 70 under the control of processing circuitry 72. Telemetry circuitry 78 may also be configured to communicate with another computing device via wireless communication techniques, or direct communication through a wired connection. In some examples, telemetry circuitry 78 may be substantially similar to telemetry circuitry 61 of IMD 16 described above, providing wireless communication via an RF or proximal inductive medium. In some examples, telemetry circuitry 78 may include an antenna, which may take on a variety of forms, such as an internal or external antenna.
  • Examples of local wireless communication techniques that may be employed to facilitate communication between device 70 and another computing device include RF communication according to the 802.11 or Bluetooth specification sets, infrared communication (e.g., according to the IrDA standard), or other standard or proprietary telemetry protocols. In this manner, other external devices may be capable of communicating with device 70 without needing to establish a secure wireless connection.
  • External device 70 may be configured to send, via telemetry circuitry 78, information to an IMD (e.g., IMD 16).
  • external device 70 may send information to the IMD indicating that a user is interacting with user interface 76 (e.g., interacting with an application of external device 70.)
  • external device 70 may include one or more sensors (e.g., heart rate monitor, accelerometer/pedometer) configured to sense physiological parameters of a patient.
  • External device 70 may send physiological parameter data (e.g., heart rate, accelerometer readings) to the IMD via telemetry circuitry 78.
  • Power source 80 delivers operating power to the components of device 70.
  • Power source 80 may include a battery and a power generation circuit to produce the operating power.
  • the battery may be rechargeable to allow extended operation.
  • processing circuitry 72 may be configured to perform at least some of the functions of processing circuitry 57, possibly in conjunction with processing circuitry 57.
  • IMD 16 may transmit information such as information indicative of one or more signals received from patient tissue to device 70.
  • Processing circuitry 72 may evaluate the one or more signals (e.g., compare signals to baseline or known CMAP or EMG signals in memory), and determine whether the one or more signals are indicative of volitional movement of a tongue of the patient similar to the description for processing circuitry 57.
  • the processing circuitry that may be configured to perform the example techniques described in this disclosure includes processing circuitry 57, processing circuitry 72, or a combination of processing circuitry 57 and processing circuitry 72.
  • the example techniques may be performed in a medical system that includes IMD 16, where IMD 16 includes stimulation circuitry 58, sensing circuitry 56, and at least a portion of the processing circuitry (e.g., processing circuitry 57).
  • the example techniques may be performed in a medical system that includes IMD 16 and external device 70.
  • IMD 16 may include stimulation circuitry 58 and sensing circuitry 56
  • external device 70 may include at least a portion of the processing circuitry (e.g., processing circuitry 72).
  • IMD 16 and external device 70 may be configured to calibrate signals received from patient tissue that are known to correspond to volitional movement of the patient’s tongue, and save the signal data corresponding to known volitional movement to a database in memory (e.g., memory 74, signal database 64).
  • processing circuitry 57 may be configured to change a therapy state of IMD 16 to a CALIBRATION therapy state.
  • processing circuitry 72 may be configured to send instructions to IMD 16 instructing IMD 16 to change to a CALIBRATION therapy state.
  • a user e.g., the patient
  • calibration program 73 may be stored in memory of IMD 16 as well.
  • processing circuitry 72 may be configured to display, based on instructions stored in calibration program 73, one or more sets of instructions on a display device of external device 70.
  • the display device may enable display of user interface 76.
  • the one or more sets of instructions may instruct the patient to engage in one or more actions. For example, one set of instructions may instruct the patient to stick their tongue out. A second set of instructions may instruct the patient to waggle their tongue from side to side. A third set of instructions may instruct the patient to waggle their tongue up and down. A fourth set of instructions may instruct the patient to make a palatal click with their tongues. A fifth set of instructions may instruct the patient to perform a hard swallow.
  • the one or more sets of instructions may be designed to elicit one or more signals from patient tissue corresponding to the tongue motions in the instructions.
  • Processing circuitry 72 and/or processing circuitry 57 may be configured to receive one or more signals from patient tissue while each set of instructions is displayed on the display device. Processing circuitry 72 and/or 57 may save the one or more signals from patient tissue to a database in memory as a set of reference signal data indicative of volitional movement of a tongue of the patient. In some examples, processing circuitry 72 and/or 57 may save the one or more signals to a database in memory 74 and/or 60 as associated with the specific action or motion shown in the set of instructions while the one or more signals were received. In this way, processing circuitry 72 and/or 57 may build a database of signals from patient tissue known to correspond to volitional movements of the patient’s tongue.
  • processing circuitry 72 and/or 57 may save the one or more signals that are associated with a specific action or motion to a database in memory 74 and/or 60 as control inputs to control a therapy state of IMD 16. For example, through calibration program 73, processing circuitry 72 and/or 57 may allow the patient to program specific tongue motions to change the therapy state of IMD 16. For example, processing circuitry 72 and/or 57 may save a set of signals associated with a hard swallow as a control input to change the therapy state of IMD 16 to an OFF therapy state. In some examples, processing circuitry 72 and/or 57 may save a set of signals associated with a palatal click as a control input to change the therapy state of IMD 16 to an ON therapy state.
  • processing circuitry 72 and/or 57 may save a set of signals associated with waggling the tongue from side to side as a control input to change the therapy state of IMD 16 to a SNOOZE therapy state.
  • Processing circuitry 72 and/or 57 may allow the patient to program any volitional tongue motion as a control input for changing IMD 16 to any therapy state.
  • the control inputs may correspond to changing settings of therapy provided by IMD 16 (e.g., stimulation intensity). In this way, processing circuitry 72 and/or 57 may allow the patient to program any number of control inputs corresponding to volitional tongue movements to control therapy of IMD 16.
  • processing circuitry 72 and/or 57 may compare the first set of one or more signals to a second set of one or more signals stored in a database in memory as a set of reference signal data known to correspond to volitional movement of the tongue of the patient. Processing circuitry 72 and/or 57 may determine, based at least in part on the comparison, whether the first set of one or more signals is indicative of volitional movement of the tongue of the patient. In some examples, the processing circuitry may determine that the first set of one or more signals from patient tissue satisfy a threshold similarity with the second set of one or more signals (the reference signal data) known to correspond to volitional movement. In response, processing circuitry 72 and/or 57 may determine that the one or more signals are indicative of volitional movement of the tongue of the patient.
  • processing circuitry 72 and/or 57 may determine if the one or more signals are indicative of a control input. For example, processing circuitry may determine that the one or more signals correspond to a specific action or motion performed by the patient (e.g., a hard swallow). For example, the one or more signals may satisfy a threshold similarity with a set of one or more signals (reference signal data) saved in memory 74 and/or 50 as corresponding to a control input. For example, the one or more signals may satisfy a threshold similarity with a set of reference signals corresponding to a hard swallow and saved as a control input to turn IMD 16 to an OFF therapy state.
  • processing circuitry 72 and/or 57 may control therapy of IMD 16 based on the control input corresponding to the specific action. For example, in response to determining that the one or more signals correspond to a hard swallow, processing circuitry 72 and/or 57 may turn IMD 16 to an OFF therapy state.
  • FIG. 5 is an example graph 500 illustrating an example CMAP signal 502 and EMG signal 512.
  • the processing circuitry of the IMD may be configured to determine whether the one or more signals from patient tissue are evoked signals.
  • CMAP signal 502 may be evoked due to the delivery of electrical stimulation signals.
  • EMG signal 512 may be a result of voluntary motion of a patient’s tongue.
  • the electrical stimulation signals may evoke a signal response from patient tissue (e.g., one or more CMAP signals).
  • the evoked signals from patient tissue may be indicative of the non-volitional movement of the tongue caused by the therapeutic stimulation signal.
  • the processing circuitry of the IMD may be configured to determine that the one or more signals are evoked signals (e.g., CMAP signals) indicative of nonvolitional movement of the tongue of the patient, and thereby determine that the one or more signals from the patient tissue are not indicative of volitional movement of the tongue of the patient.
  • CMAP signals may be regularly evoked from patient tissue due to the OSA therapy.
  • CMAP signals may be evoked from patient tissue at the same rate that the IMD provides electrical stimulation pulses to patient tissue, i.e., the signal data may be synchronized to the stimulation pulses.
  • the processing circuitry of the IMD may be configured to determine whether one or more signals received from patient tissue are indicative of volitional movement of the tongue of the patient based on the rate at which the one or more signals are received.
  • processing circuitry of the IMD may determine that the rate at which a first set of one or more signals is received is equivalent or very close to the rate at which the IMD is delivering electrical stimulation pulses, and in response, determine that the first set of one or more signals is a set of evoked signals and therefore not indicative of volitional movement of the tongue of the patient.
  • the processing circuitry may determine that a second set of one or more signals is not received at a similar rate to the rate at which the IMD delivers electrical stimulation pulses. In response, the processing circuitry may determine that the second set of one or more signals is not evoked and therefore indicative of volitional movement of the tongue.
  • the IMD may receive a set of one or more signals where some signals within the set may indicate volitional movement of the tongue while others may indicative nonvolitional movement of the tongue. For example, a first group of one or more signals of a set of signals may be received at a rate similar to the rate at which the IMD delivers electrical stimulation pulses. A second group of one or more signals of the set of signals may be received at a rate dissimilar to the rate at which the IMD delivers electrical stimulation pulses. The processing circuitry may determine that the first group of signals is not indicative of volitional movement of the tongue of the patient, and may determine that the second group is indicative of volitional movement of the tongue of the patient.
  • CMAP signal 502 may include one or more peaks (e.g., peak 504) and/or valleys that greatly exceed the normal amplitude of peaks and/or valleys in the non-evoked EMG signal 512.
  • CMAP signal 502 includes peak 504 that is much larger than peak 514 of EMG signal 512.
  • processing circuitry of the IMD may determine whether one or more signals are indicative of volitional movement of the tongue based on whether the one or more peaks of the one or more signals exceed a threshold. For example, the processing circuitry may determine that peak 504 exceeds peak threshold 520, and in response, determine that CMAP signal 502 is an evoked signal that is not indicative of volitional movement of the tongue of the patient.
  • the processing circuitry may determine that peak 514 does not exceed peak threshold 520, and in response, determine that EMG signal 512 is not an evoked signal and therefore indicative of volitional movement of the tongue of the patient.
  • the IMD may include multiple different peak thresholds in memory.
  • the IMD may include a nonvolitional peak threshold and a volitional peak threshold, wherein the nonvolitional peak threshold is higher than the volitional peak threshold.
  • the processing circuitry may determine that signals with peaks exceeding the nonvolitional peak threshold are not indicative of volitional movement of the tongue, whereas processing circuitry may determine that peaks below the volitional peak threshold are indicative of volitional movement of the tongue.
  • An evoked CMAP signal may be considered as including two components: an artifact component and non-artifact component.
  • CMAP signal 502 includes artifact component 506 and non-artifact component 508.
  • the processing circuitry may determine that a signal that contains an artifact component is an evoked signal, and therefore not indicative of volitional movement of the tongue of the patient.
  • processing circuitry may analyze any number of features of one or more received signals in order to determine whether the one or more signals are indicative of volitional movement of the tongue of the patient. For example, processing circuitry may compare the mean of one or more signals to a mean threshold, a median of one or more signals to a median threshold, a valley of one or more signals to a valley threshold, etc. Processing circuitry may also analyze any derivation of signal features, e.g., a standard deviation or variance of the signal.
  • one or more methods may be used, for example as described in “Automatic Detection of Stimulation Artifacts to Isolate Volitional from Evoked EMG Activity” by Ana Caroline C. de Sousa et. al., IFAC- PapersOnLine, 51-27 (2016) 282-287 (available at https://doi.Org/10.1016/j.ifacol.2018.l l.628).
  • FIG. 6 is an example graph 600 illustrating a first CMAP signal 602 and a second CMAP signal 604.
  • First CMAP signal 602 may be received by an IMD at a different time than second CMAP signal 604, although they are displayed in FIG. 6 together for convenience.
  • CMAP signals e.g., CMAP signals 602 and 604
  • OSA therapy e.g., electrical stimulation
  • CMAP signals 602 and 604 may be regularly evoked from patient tissue due to the OSA therapy.
  • only one CMAP signal 602 and only one CMAP signal 604 is shown in FIG.
  • the IMD may receive a series of regular CMAP signals similar to CMAP signal 602 and/or a series of regular CMAP signals similar to CMAP signal 604 in response to the OSA therapy.
  • the series of CMAP signals evoked due to OSA therapy while the tongue is in the given position may all be similar to one another (e.g., have the same or substantially similar signal profiles on a graph).
  • the signal profile of the series of CMAP signals evoked due to OSA therapy while the tongue is in the new position may have different signal profiles than the CMAP signals evoked in the original position.
  • a substantial change in the signal profile of the CMAP signal may be indicative of a changed position of the tongue of the patient.
  • the processing circuitry of the IMD may determine whether a first series of CMAP signals differ substantially from a second series of CMAP signals.
  • the signal profile for a first series of CMAP signals may be represented by first CMAP signal 602
  • the signal profile for a second series of CMAP signals may be represented by second CMAP signal 604.
  • the processing circuitry may determine, for each point along one of the signal profiles, whether the corresponding point along the other signal profile differs by more than a threshold percentage.
  • the processing circuitry may determine whether a pair of corresponding points along CMAP signals 602 and 604 differ by a threshold value (e.g., a threshold mV value).
  • a threshold value e.g., a threshold mV value
  • FIG. 7 is a flowchart illustrating an example of method of controlling therapy of an IMD.
  • the example of FIG. 7 is described with respect to processing circuitry, examples of which include processing circuitry 57 and 72 from FIGS. 3 and 4 respectively.
  • Methods are disclosed for controlling a therapy state of IMD 16 in response to measurement of patient physiological parameters. In this way, IMD 16 may ensure that OSA therapy is provided to the patient when therapy is needed, and not provided when not needed.
  • the physiological parameters include one or more signals sensed from patient tissue.
  • a method may include receiving, by processing circuitry 57 via sensing circuitry 56 electrically connected to one or more electrodes in close proximity to one or more of a hypoglossal nerve and protrusor muscle of the patient, one or more signals from patient tissue (700).
  • the one or more signals received may include one or more of EMG signals and/or CMAP signals indicative of patient tongue motion.
  • CMAP signals may be evoked, in that, CMAP signals may be generated in muscles in response to (e.g., caused by) delivery of electrical stimulation.
  • the method may include delivering, via stimulation circuitry 56, one or more electrical stimulation pulses to the patient tissue, and sensing, via the one or more electrodes, one or more CMAP signals from the patient tissue evoked in response to the delivery of the one or more electrical stimulation pulses.
  • EMG signals are biomedical signals that reflect electrical currents generated in muscles during muscle contraction, representing neuromuscular activities. Therefore, EMG signals need not be evoked.
  • the method may further be include determining whether the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient (702). In one instance, the method may include determining that the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient. In another instance, the method may include determining that the one or more signals from the patient tissue are not indicative of volitional movement of the tongue of the patient. In some examples where processing circuitry 57 determines that the one or more signals are not indicative of volitional movement of the tongue, processing circuitry 57 may determine that the one or more signals are indicative of non-volitional movement of the tongue (e.g., from delivery of OSA therapy, from reflexive tongue motion, etc.). In some examples where processing circuitry 57 determines that the one or more signals are not indicative of volitional movement of the tongue, processing circuitry 57 may determine that the one or more signals do not satisfy a threshold likeliness of being indicative of volitional tongue movement.
  • processing circuitry 57 may be configured to compare the one or more signals to one or more sets of reference signal data stored in a database in memory.
  • the reference signal data may be known to correspond to volitional movement.
  • the reference signal data may be known to correspond to nonvolitional movement (e.g., movement evoked by stimulation/OSA therapy).
  • the one or more sets of reference signal data may be stored in signal database 64.
  • the one or more sets of reference signal data may be stored in memory of a different computing device of the system that includes IMD 16, with which IMD 16 is in communication (e.g., via telemetry circuitry 61).
  • one or more sets of reference signal data correspond to population averages of signal data from tongue movements from a plurality of patients.
  • one or more sets of reference signal data known to correspond to volitional tongue movement may be calculated from population averages of signal data from volitional tongue movements from a plurality of patients.
  • one or more sets of reference signal data known to correspond to non-volitional tongue movement may be calculated from population averages of signal data from non-volitional tongue movements from a plurality of patients.
  • the one or more sets of reference signal data (e.g., either volitional or nonvolitional) may reflect signal patterns corresponding specifically to tongue movement of the patient from which the one or more signals were received.
  • IMD 16 may collect one or more sets of reference signal data corresponding to volitional tongue movements.
  • the patient may perform one or more volitional tongue motions, and the one or more signals received from the patient’s tongue during the motions may be stored in signal database 64 as associated with the patient, where each of the one or more signals is associated with one or more of the volitional tongue motions.
  • IMD 16 may store volitional tongue motions in signal database 64 as control inputs for patient to control a therapy state of IMD 16.
  • IMD 16 may store one or more signals corresponding to a hard swallow as a control input to turn IMD 16 to an OFF therapy state.
  • processing circuitry 57 may utilize machine learning based techniques.
  • therapy state programs 63 (or another device in communication with IMD 16) may include a machine learning program.
  • Processing circuitry 57 (or processing circuitry of another device in communication with IMD 16) may receive the reference signal data known to correspond to volitional movement of the tongue. Using the reference signal data, processing circuitry 57 may train a neural network to generate a trained neural network that identifies whether a sensed signal corresponds to volitional movement or not.
  • IMD 16 or another device like a programmer may store the trained neural network (e.g., as part of therapy state programs 63).
  • the input to the trained neural network may be the sensed signal, and the output from the trained neural network may be information indicative of whether the one or more signals, from the patient tissue, are indicative of volitional movement of the tongue of the patient.
  • processing circuitry 57 may determine that the one or more signals from patient tissue are indicative of volitional tongue movement. In some examples, if the one or more signals from the patient tissue do not satisfy a threshold similarity with the one or more sets of reference signal data corresponding to volitional movement, processing circuitry 57 may determine that the one or more signals from patient tissue are not indicative of volitional tongue movement. If the one or more signals from the patient tissue satisfy a threshold similarity with the one or more sets of reference signal data corresponding to nonvolitional movement, processing circuitry 57 may determine that the one or more signals from patient tissue are not indicative of volitional tongue movement.
  • Processing circuitry 57 may further determine that the one or more signals from patient tissue are indicative of nonvolitional movement.
  • processing circuitry 57 may be configured to receive a set of one or more signals from the patient tissue and apply the set of one or more signals to a machine learning algorithm (e.g., a machine learning algorithm stored in therapy state programs 63), wherein the machine learning algorithm is trained to receive a set of one or more signals as input, and output whether the set of one or more signals are indicative of volitional movement of the tongue of the patient.
  • a machine learning algorithm e.g., a machine learning algorithm stored in therapy state programs 63
  • the machine learning algorithm may be trained on reference signal data corresponding to movement of the tongue of a patient that is known to be volitional or nonvolitional. In some examples, the machine learning algorithm may output information indicating that the set of one or more signals is indicative of volitional movement of the tongue of the patient. In some examples, the machine learning algorithm may output information indicating that the set of one or more signals is indicative of nonvolitional movement of the tongue of the patient.
  • processing circuitry 57 may be configured to receive a first set of one or more signals from the patient tissue and a second set of one or more signals from the patient tissue. If processing circuitry 57 receives the second set of one or more signals from the patient tissue within a threshold amount of time after receiving the first set of one or more signals, processing circuitry 57 may determine that the first and/or second sets of signals are indicative of volitional movement of the patient’s tongue. For example, processing circuitry 57 may receive a second set of one or more signals from the patient tissue within thirty seconds of receiving a first set of one or more signals from the patient tissue. Processing circuitry 57 may determine that thirty seconds satisfies the threshold amount of time.
  • processing circuitry 57 may determine whether the one or more signals from patient tissue are indicative of volitional tongue movement of the patient based on receiving a threshold number of sets of one or more signals all within a threshold amount of time, and/or wherein each consecutively received set of one or more signals is received within a threshold amount of time from the previous set. For example, processing circuitry 57 may receive a first set of one or more signals from patient tissue, a second set, and a third set. Processing circuitry 57 may receive the second set thirty seconds after the first set, and may receive the third set forty seconds after the second set. A set number threshold stored in memory may be three sets. A time period threshold stored in memory may be five minutes. In some examples, the time period threshold may be any amount of time.
  • An interval time threshold stored in memory may be sixty seconds. In some examples, an interval time threshold may be more or less than sixty seconds.
  • Processing circuitry 57 may determine that the three sets satisfies the set number threshold. Processing circuitry 57 may determine that the three sets of one or more signals were all received within a time period of seventy seconds, and may determine that the time period of seventy seconds satisfies the time period threshold. Processing circuitry 57 may determine that each interval between sets (thirty seconds and forty seconds) satisfies the interval time threshold.
  • processing circuitry 57 may determine that the first, second, and/or third sets of one or more signals are indicative of volitional tongue movement of the patient. In some examples, processing circuitry 57 may determine that the sets of one or more signals are indicative of volitional tongue movement based only on satisfaction of the interval time threshold.
  • processing circuitry 57 may be configured to determine a time of day corresponding to the one or more signals (e.g., the time of day at which the one or more signals were received). For example, processing circuitry 57 may receive the time of day from an internal clock of IMD 16. In some examples processing circuitry 57 may receive the time of day from an external device in communication with IMD 16 via telemetry circuitry 61.
  • Processing circuitry 57 may determine that the one or more signals from patient tissue are indicative of volitional tongue movement of the patient if the time of day is within a first interval, and processing circuitry 57 may determine that the one or more signals are not indicative of volitional tongue movement of the patient if the time of day is within a second interval.
  • a first interval may be 11AM to 3PM, and processing circuitry 57 may receive the one or more signals at 12: 10PM.
  • Processing circuitry 57 may determine that 12: 10 PM is within the first interval and that the one or more signals are indicative of volitional tongue movement.
  • a second interval may be 1AM to 3AM, and processing circuitry 57 may receive the one or more signals at 1:30AM.
  • Processing circuitry 57 may determine that 1:30AM is within the second interval and that the one or more signals are not indicative of volitional tongue movement.
  • processing circuitry 57 may be configured to determine one or more movements of the patient corresponding to the one or more signals (e.g., one or more movements of the patient at or near the time the one or more signals were received).
  • IMD 16 or another device in communication with IMD 16 may include one or more accelerometers to track patient movement (e.g., walking, breathing, etc.).
  • processing circuitry 57 may determine, based on pedometer or other accelerometer signals, that the patient is walking, running, jumping, etc.
  • processing circuitry 57 may determine that the one or more signals are indicative of volitional tongue movement. In some examples, processing circuitry 57 may determine that a breathing rate of the patient exceeds a threshold breathing rate. In response to determining that the breathing rate of the patient exceeds a threshold breathing rate, processing circuitry 57 may determine that the one or more signals are indicative of volitional tongue movement.
  • processing circuitry 57 may be configured to determine a heart rate of the patient at or near the time the one or more signals were received.
  • IMD 16 or another device in communication with IMD 16 may include a heart rate monitor.
  • Processing circuitry 57 may determine that relatively high measured heart rates indicate that the patient is awake, and therefore not in need of OSA therapy, and may also determine that relatively low measure heart rates indicate that the patient is asleep, and may need OSA therapy.
  • processing circuitry 57 may determine that, if the measured heart rate of the patient exceeds a heart rate threshold, the one or more signals are indicative of volitional patient movement.
  • a heart rate threshold may be 100 beats per minute (bpm), and the measured heart rate may be 120 bpm.
  • Processing circuitry 57 may determine that 120 bpm exceeds the heart rate threshold and that the one or more signals received from patient tissue at or near the time of the measured heart rate are indicative of volitional tongue movement.
  • processing circuitry 57 may determine that, if the measured heart rate of the patient satisfies a lower threshold, the one or more signals are indicative of nonvolitional patient movement.
  • a lower heart rate threshold may be 48 bpm, and the measured heart rate may be 45 bpm.
  • Processing circuitry 57 may determine that 45 bpm satisfies the lower heart rate threshold, and that the one or more signals received from patient tissue at or near the time of the measured heart rate are indicative of nonvolitional tongue movement.
  • processing circuitry 57 may determine whether signals from patient tissue are indicative of volitional movement of the tongue with greater certainty. Processing circuitry 57 may analyze the time of day, posture, heart rate, and other physiological parameters to confirm determinations made by processing circuitry 57 based on the signals received from patient tissue.
  • processing circuitry 57 may be configured to deliver, via stimulation circuitry 58 of IMD 16, one or more electrical stimulation pulses to the patient tissue. Electrical stimulation may evoke CMAP signals generated in muscles in response to (e.g., caused by) delivery of the electrical stimulation.
  • IMD 16 may be in an ON therapy state, in which processing circuitry 57 is configured to provide OSA therapy to the tongue of the patient by causing the stimulation circuitry to deliver a therapeutic stimulation signal to patient tissue.
  • Processing circuitry 57 may sense, via one or more electrodes, the one or more signals as one or more evoked signals from the patient tissue evoked in response to the delivery of the one or more electrical stimulation pulses. Processing circuitry 57 may receive the one or more signals within a threshold amount of time after delivering the one or more electrical stimulation pulses, and in response, determine that the one or more signals are not indicative of volitional tongue movement. For example, processing circuitry 57 may receive the one or more signals within 10ms of delivering the stimulation pulses, and may determine that the one or more signals are not indicative of volitional tongue movement. In some examples, the threshold amount of time may differ depending on the stimulation rate at which IMD 16 provides OSA therapy.
  • processing circuitry 57 may receive a plurality of sets of signals from patient tissue, where each set of the plurality of sets of signals is received at regular intervals, and each set of the plurality of sets of signals is received shortly after delivery of the one or more electrical stimulation pulses. In response, processing circuitry 57 may determine that the plurality of sets of signals are indicative of nonvolitional movement of the tongue of the patient.
  • IMD 16 may be in an ON therapy state, in which processing circuitry 57 is configured to provide OSA therapy to the tongue of the patient by causing the stimulation circuitry to deliver one or more electrical stimulation pulses at regular intervals to patient tissue.
  • the one or more electrical stimulation pulses at regular intervals may cause regular CMAP signals to be generated in response to the stimulation pulses.
  • processing circuitry 57 may be configured to pause delivery of the one or more electrical stimulation pulses. For example, processing circuitry 57 may pause delivery for a length of time or a number of stimulation pulses. In some examples, processing circuitry 57 may pause delivery of the one or more electrical stimulation pulses for five seconds. In some examples, processing circuitry 57 may not deliver the next five stimulation pulses.
  • processing circuitry 57 may sense for a second set of one or more signals from the patient tissue. Because stimulation has been paused, received signals may not be evoked CMAP signals, although a first signal during the pause may be a CMAP signal received in response to the previous electrical stimulation pulse. Processing circuitry 57 may receive a second set of one or more signals during the pause, and in response, determine that the first and/or second set of one or more signals are indicative of volitional tongue movement. In some examples, processing circuitry 57 may not receive a second set of one or more signals during the pause, and in response, determine that the first set of one or more signals are not indicative of volitional tongue movement.
  • processing circuitry 57 may use any combination of methods to determine whether the one or more signals from the patient tissue are indicative of volitional movement of a tongue of the patient. For example, processing circuitry 57 may determine that the one or more signals from the patient tissue do not satisfy a threshold similarity with one or more sets of reference signal data in memory corresponding to volitional movement, however, processing circuitry 57 may receive ten sets of such one or more signals from patient tissue that do not satisfy the threshold within a short time period (e.g., 5 minutes), and processing circuitry 57 may determine that the time of day is between 12PM and 1PM. Based on this combination, processing circuitry 57 may determine that the one or more signals from patient tissue are indicative of volitional movement of the tongue of the patient, despite the one or more signals not satisfying the threshold similarity with reference signal data.
  • a short time period e.g., 5 minutes
  • processing circuitry 57 may determine that - for a threshold number of methods for determining whether the one or more signals are indicative of voluntary tongue movement - processing circuitry 57 determined that the one or more signals are indicative of volitional tongue movement.
  • a method threshold may be 70% of methods used should indicate that the one or more signals are indicative of volitional tongue movement. If, for only one out of four methods used, processing circuitry 57 determines that the one or more signals are indicative of volitional tongue movement, processing circuitry 57 may determine that the method threshold has not been satisfied and may determine that the one or more signals are not indicative of volitional tongue movement.
  • the method may further include controlling therapy of an IMD (e.g., IMD 16) configured to deliver therapy for sleep apnea (704).
  • processing circuitry of the IMD may be configured to automatically change a therapy state of the IMD to an appropriate therapy state with, without, and/or despite patient input.
  • the IMD may interpret volitional movements of the tongue by the patient as instructions to change the therapy state.
  • Therapy state programs 63 may include instructions for execution by processing circuitry 57 to control therapy states of IMD 16.
  • therapy state programs 63 may include instructions for when to transition between an ON therapy state, OFF therapy state, DELAY therapy state, SNOOZE therapy state, and CALIBRATION therapy state. The preceding list is non -exhaustive.
  • processing circuitry 57 in the ON therapy state, is configured to provide OSA therapy to a tongue of the patient by causing stimulation circuitry 58 to deliver therapeutic stimulation signals to patient tissue. In some examples, in the OFF therapy state, the processing circuitry 57 is configured to not deliver electrical stimulation pulses for treating sleep apnea. In some examples, in the OFF therapy state, processing circuitry 57 may still sense for signals from patient tissue via the one or more electrodes on the one or more leads attached to IMD 16.
  • IMD 16 may be in an ON therapy state, and processing circuitry 57 may determine that the one or more signals from patient tissue are indicative of volitional movement of the tongue of the patient. This may mean that, although IMD 16 has been providing OSA therapy, the patient is currently awake and not in need of OSA therapy. For example, the patient may have accidentally started a therapy program through interaction with an external device (e.g., a smartphone) in communication with IMD 16. For example, while fishing around in their pockets for a stick of gum, the patient may accidentally click a series of buttons to send an instruction to IMD 16 to enter an ON therapy state. In some examples, the patient may have been asleep and benefitting from OSA therapy, however, the patient has now awoken to use the restroom.
  • an external device e.g., a smartphone
  • processing circuitry 57 may change the therapy state of IMD 16 from the ON therapy state to an OFF therapy state. In this way, IMD 16 may allow the patient full control of their tongue while they are awake.
  • IMD 16 may be in an OFF therapy state, and processing circuitry 57 may determine that no signals indicative of volitional movement of the tongue of the patient have been received for a time period. For example, the patient may have fallen asleep without instructing IMD 16 to turn ON and provide OSA therapy. Processing circuitry 57 may change, at least partially in response to determining that no signals have been received over the time period, the therapy state of IMD 16 to an ON therapy state. For example, processing circuitry 57 may determine that no signals have been received from patient tissue for a time period of 15 minutes. In some examples the time period may be any length of time.
  • processing circuitry 57 may change the therapy state of IMD 16 to an ON therapy state.
  • processing circuitry 57 may change the therapy state of IMD 16 to an ON therapy state partially in response to determining a current time. For example, processing circuitry 57 may determine that no signals have been received from patient tissue for the time period, and that the current time is 11 :45PM. In response to both determining that no signals have been received from patient tissue for the time period and that the current time is within a nighttime time interval, processing circuitry 57 may change the therapy state of IMD 16 to an ON therapy state.
  • processing circuitry 57 may change the therapy state of IMD 16 at least partially based on other physiological parameters of the patient as well (e.g., accelerometers, heart rate, etc.). In this way, IMD 16 may provide OSA therapy to a patient even when the patient forgets to turn on the OSA therapy.
  • IMD 16 may be in an OFF therapy state, and processing circuitry may receive an instruction from an external device (e.g., a smartphone) to change a therapy state of the IMD to an ON therapy state.
  • an external device e.g., a smartphone
  • processing circuitry 57 may be configured to change, in response to receiving the instruction, the therapy state to a DELAY therapy state, wherein in the DELAY therapy state, IMD 16 may be configured to wait a period of time before transitioning into the ON therapy state to deliver OSA therapy.
  • the DELAY therapy state may occur for a period of time of fifteen minutes before IMD 16 automatically transitions to the ON therapy state. This delay may allow the patient to fall asleep before IMD 16 provides OSA therapy.
  • IMD 16 may be in a therapy state that is neither OFF nor ON when IMD 16 receives the instruction to change the therapy state to an ON therapy state.
  • Processing circuitry 57 may change whatever the current therapy state is to the DELAY therapy state.
  • IMD 16 may be in an ON therapy state, and processing circuitry 57 may determine that the one or more signals from patient tissue are indicative of volitional movement of the tongue of the patient.
  • a patient may temporarily awake from slumber, only to return to sleep moments later.
  • processing circuitry 57 may change the therapy state of IMD 16 from the ON therapy state to a DELAY therapy state.
  • IMD 16 may be configured to stop providing OSA therapy and wait a period of time before transitioning back into the ON therapy state to deliver OSA therapy.
  • the DELAY therapy state may occur for a period of time of two minutes before IMD 16 automatically transitions to the ON therapy state.
  • the period of time IMD 16 is configured to wait (the delay period) in the DELAY therapy state may differ depending on how IMD 16 transitioned to the DELAY therapy state.
  • IMD 16 may be in an OFF therapy state and processing circuitry 57 may change the therapy state of IMD 16 to a DELAY therapy state in response to receiving instructions from an external device to change the therapy state to an ON therapy state. Having just received an instruction from external device, processing circuitry 57 may determine that it is unlikely that the patient is asleep, and may set a first delay period such that the delay period allows the patient to fall asleep before IMD 16 starts providing OSA therapy.
  • the first delay period set in response to entering the DELAY therapy state in this manner may be 10-15 minutes.
  • the patient may adjust the first delay period (e.g., through an app on a smartphone in communication with IMD 16).
  • IMD 16 may be in an ON therapy state and processing circuitry 57 may change the therapy state of IMD 16 to the DELAY therapy state in response to determining that one or more received signals from patient tissue are indicative of volitional movement of the patient’s tongue.
  • the patient may have only temporarily awoken from slumber, or entered a short period of light sleep, only to return to sleep moments later. It may be advantageous to continue to provide OSA therapy to the patient as soon as the patient returns to sleep.
  • Processing circuitry 57 may set a second delay period when IMD 16 enters the DELAY therapy state in this manner that is relatively short to ensure that IMD 16 continues to provide OSA therapy while the patient is sleeping.
  • the second delay period may be 1-2 minutes.
  • sleep studies performed on the patient may indicate a preferred amount of time for the second delay period, and a physician may adjust a second delay period (e.g., through an external programmer in communication with IMD 16) to best fit the patient’s sleep cycles.
  • processing circuitry 57 may set a longer delay period (first delay period) when changing IMD 16 from an OFF therapy state to an ON therapy state than the delay period (second delay period) when changing IMD 16 from an ON therapy state to a DELAY therapy state.
  • processing circuitry 57 may receive an indication that the patient may be awake. For example, processing circuitry 57 may determine that one or more signals received from the patient tissue are indicative of volitional movement. In some examples, processing circuitry 57 may receive information from an external device that the patient is interacting with the external device (e.g., playing a game on their phone). In response to receiving an indication that the patient may be awake, and while IMD 16 is in the DELAY therapy state, processing circuitry 57 may restart or extend the delay period timer.
  • processing circuitry 57 may track an amount of time that IMD 16 is in the DELAY therapy state. If IMD 16 is in the DELAY therapy state for an extended period of time, it may mean that the delay period timer has been restarted or extended many times (e.g., in response to processing circuitry 57 receiving an indication that the patient may be awake), and the patient may very likely be awake. In some examples, processing circuitry 57 may change a therapy state of IMD 16 from a DELAY therapy state to an OFF therapy state in response to determining that the amount of time that IMD 16 has been in the DELAY therapy state exceeds a threshold amount of time.
  • the threshold amount of time may be 1.5 hours, and processing circuitry may determine that IMD 16 has been in the DELAY therapy state for 1.6 hours. In response to determining that IMD 16 has been in the DELAY therapy state longer than the threshold amount of time, processing circuitry 57 may change the therapy state of IMD 16 from the DELAY therapy state to an OFF therapy state.
  • processing circuitry 57 may track a number of times that the delay period timer has been restarted or extended while IMD 16 is in the same DELAY therapy state. Even if IMD 16 has not been in the DELAY therapy state for an extended period of time, sometimes the sheer volume of indications that the patient may be awake can be sufficient to turn off OSA therapy. In some examples, processing circuitry 57 may change a therapy state of IMD 16 from a DELAY therapy state to an OFF therapy state in response to determining that the number of times the delay period timer has been restarted or extended exceeds a threshold number. For example, the threshold number may be 20 times, and processing circuitry may determine that the delay period timer has been restarted and/or extended 22 times.
  • processing circuitry 57 may change the therapy state of IMD 16 from the DELAY therapy state to an OFF therapy state.
  • processing circuitry 57 may determine when to deliver stimulation pulses to patient tissue to provide OSA therapy. For example, processing circuitry 57 may determine, based on the one or more received signals from patient tissue, that the tongue of the patient is not obstructing an airway of the patient. In response to determining that the tongue is not obstructing the airway, processing circuitry 57 may not deliver electrical stimulation pulses to patient tissue.
  • processing circuitry 57 may determine, based on the one or more received signals from patient tissue, that the tongue of the patient is obstructing an airway of the patient. In response to determining that the tongue is obstructing the airway, processing circuitry 57 may deliver electrical stimulation pulses to patient tissue (e.g., provide OSA therapy).
  • patient tissue e.g., provide OSA therapy.
  • IMD 16 may include one or more strain gauges attached to one or more of leads 20 and 21. Based on the strain gauges, IMD 16 may determine a position of the tongue of the patient.
  • the patient may be awake and IMD 16 may be configured to stop sensing for signals from patient tissue in order to conserve power in power source 62.
  • IMD 16 may receive one or more indications that the patient may be awake.
  • processing circuitry 57 may determine that one or more signals received from the patient tissue are indicative of volitional movement.
  • processing circuitry 57 may receive information from an external device that the patient is interacting with the external device (e.g., playing a game on their phone).
  • processing circuitry 57 may determine that the time of day is during daytime hours when the patient is most likely to be awake (e.g., based on a tracked history of patient activity saved to memory 60, based on population data for most active hours of the day on average). In some examples, processing circuitry may receive other indications that the patient may be awake (e.g., high heart rate, accelerometer data indicating patient is walking or running, high breathing rate, etc.). In response to receiving one or more indications that the patient may be awake, processing circuitry 57 may change a therapy state of IMD 16 to a SNOOZE therapy state. In the SNOOZE therapy state, processing circuitry 57 may be configured to stop sensing for signals from patient tissue for a period of time.
  • processing circuitry 57 may be configured to stop sensing for signals from patient tissue for an hour.
  • the SNOOZE period of time may be any period of time, and may be saved in memory 60.
  • the SNOOZE period of time may be set by an external device (e.g., by the patient with a smartphone, by a physician with an external programmer).
  • processing circuitry 57 may change the therapy state of IMD 16 to a SNOOZE therapy state in response to receiving a threshold number of indications that the patient is awake. For example, processing circuitry may receive a first set of one or more signals from the patient tissue and a second set of one or more signals from the patient tissue within a threshold time period from receiving the first set. In response to receiving the second set of one or more signals from patient tissue within the threshold amount of time, processing circuitry 57 may change the therapy state of IMD 16 to a SNOOZE therapy state.
  • processing circuitry 57 may receive a plurality of sets of one or more signals from patient tissue within a threshold amount of time and determine that each of the sets of the plurality of sets are indicative of volitional movement of a tongue of the patient. In addition, processing circuitry 57 may determine that the time of day is during high- activity daytime hours, and receive information from an external device that the patient is interacting with an external device. Based on the determined and received indications that the patient is awake, processing circuitry 57 may change the therapy state of IMD 16 to a SNOOZE therapy state. The threshold number and type of indications necessary for processing circuitry 57 to change the therapy state of IMD 16 to a SNOOZE therapy state may be saved in memory 60. The threshold number and type of indications may be set by an external device (e.g., by the patient with a smartphone, by a physician with an external programmer).
  • an external device e.g., by the patient with a smartphone, by a physician with an external programmer.
  • IMD 16 and external device 70 may be configured to calibrate signals received from patient tissue that are known to correspond to volitional movement of the patient’s tongue, and save the signal data corresponding to known volitional movement to a database in memory (e.g., memory 74, signal database 64).
  • processing circuitry 57 may be configured to change a therapy state of IMD 16 to a CALIBRATION therapy state.
  • processing circuitry 72 may be configured to send instructions to IMD 16 instructing IMD 16 to change to a CALIBRATION therapy state.
  • a user e.g., the patient
  • processing circuitry 72 may be configured to display, based on instructions stored in calibration program 73, one or more sets of instructions on a display device of external device 70.
  • the display device may enable display of user interface 76.
  • the one or more sets of instructions may instruct the patient to engage in one or more actions. For example, one set of instructions may instruct the patient to stick their tongue out. A second set of instructions may instruct the patient to waggle their tongue from side to side. A third set of instructions may instruct the patient to waggle their tongue up and down. A fourth set of instructions may instruct the patient to make a palatal click with their tongues.
  • the one or more sets of instructions may be designed to elicit one or more signals from patient tissue corresponding to the tongue motions in the instructions.
  • Processing circuitry 72 and/or processing circuitry 57 may be configured to receive one or more signals from patient tissue while each set of instructions is displayed on the display device. Processing circuitry 72 and/or 57 may save the one or more signals from patient tissue to a database in memory as a set of reference signal data indicative of volitional movement of a tongue of the patient. In some examples, Processing circuitry 72 and/or 57 may save the one or more signals to a database in memory as associated with the specific action or motion shown in the set of instructions while the one or more signals were received. In this way, processing circuitry 72 and/or 57 may build a database of signals from patient tissue known to correspond to volitional movements of the patient’s tongue.
  • processing circuitry 72 and/or 57 may save the one or more signals that are associated with a specific action or motion to a database in memory 74 and/or 60 as control inputs to control a therapy state of IMD 16. For example, through calibration program 73, processing circuitry 72 and/or 57 may allow the patient to program specific tongue motions to change the therapy state of IMD 16. For example, processing circuitry 72 and/or 57 may save a set of signals associated with a hard swallow as a control input to change the therapy state of IMD 16 to an OFF therapy state. In some examples, processing circuitry 72 and/or 57 may save a set of signals associated with a palatal click as a control input to change the therapy state of IMD 16 to an ON therapy state.
  • processing circuitry 72 and/or 57 may save a set of signals associated with waggling the tongue from side to side as a control input to change the therapy state of IMD 16 to a SNOOZE therapy state.
  • Processing circuitry 72 and/or 57 may allow the patient to program any volitional tongue motion as a control input for changing IMD 16 to any therapy state.
  • the control inputs may correspond to changing settings of therapy provided by IMD 16 (e.g., stimulation intensity). In this way, processing circuitry 72 and/or 57 may allow the patient to program any number of control inputs corresponding to volitional tongue movements to control therapy of IMD 16.
  • processing circuitry 72 and/or 57 may compare the first set of one or more signals to a second set of one or more signals stored in a database in memory as a set of reference signal data known to correspond to volitional movement of the tongue of the patient. Processing circuitry 72 and/or 57 may determine, based at least in part on the comparison, whether the first set of one or more signals is indicative of volitional movement of the tongue of the patient. In some examples, the processing circuitry may determine that the first set of one or more signals from patient tissue satisfy a threshold similarity with the second set of one or more signals (the reference signal data) known to correspond to volitional movement. In response, the processing circuitry may determine that the one or more signals are indicative of volitional movement of the tongue of the patient.
  • processing circuitry 72 and/or 57 may determine if the one or more signals are indicative of a control input. For example, processing circuitry may determine that the one or more signals correspond to a specific action or motion performed by the patient (e.g., a hard swallow). For example, the one or more signals may satisfy a threshold similarity with a set of one or more signals (reference signal data) saved in memory 74 and/or 50 as corresponding to a control input. For example, the one or more signals may satisfy a threshold similarity with a set of reference signals corresponding to a hard swallow and saved as a control input to turn IMD 16 to an OFF therapy state.
  • processing circuitry 72 and/or 57 may control therapy of IMD 16 based on the control input corresponding to the specific action. For example, in response to determining that the one or more signals correspond to a hard swallow, processing circuitry 72 and/or 57 may turn IMD 16 to an OFF therapy state.
  • the processing circuitry of the IMD in order to determine whether the one or more signals from the patient tissue are indicative of volitional movement of a tongue of a patient, the processing circuitry of the IMD may be configured to determine whether the one or more signals from patient tissue are evoked signals.
  • CMAP signals may be evoked due to the delivery of electrical stimulation signals.
  • EMG signals may be a result of voluntary motion of a patient’s tongue.
  • the electrical stimulation signals may evoke a signal response from patient tissue (e.g., one or more CMAP signals).
  • the evoked signals from patient tissue may be indicative of the non-volitional movement of the tongue caused by the therapeutic stimulation signal.
  • the processing circuitry of the IMD may be configured to determine that the one or more signals are evoked signals (e.g., CMAP signals) indicative of nonvolitional movement of the tongue of the patient, and thereby determine that the one or more signals from the patient tissue are not indicative of volitional movement of the tongue of the patient.
  • CMAP signals may be regularly evoked from patient tissue due to the OSA therapy.
  • CMAP signals may be evoked from patient tissue at the same rate that the IMD provides electrical stimulation pulses to patient tissue.
  • the processing circuitry of the IMD may be configured to determine whether one or more signals received from patient tissue are indicative of volitional movement of the tongue of the patient based on the rate at which the one or more signals are received.
  • processing circuitry of the IMD may determine that the rate at which a first set of one or more signals is received is equivalent or very close to the rate at which the IMD is delivering electrical stimulation pulses, and in response, determine that the first set of one or more signals is a set of evoked signals and therefore not indicative of volitional movement of the tongue of the patient.
  • the processing circuitry may determine that a second set of one or more signals is not received at a similar rate to the rate at which the IMD delivers electrical stimulation pulses. In response, the processing circuitry may determine that the second set of one or more signals is not evoked and therefore indicative of volitional movement of the tongue.
  • the IMD may receive a set of one or more signals where some signals within the set may indicate volitional movement of the tongue while others may indicative nonvolitional movement of the tongue. For example, a first group of one or more signals of a set of signals may be received at a rate similar to the rate at which the IMD delivers electrical stimulation pulses. A second group of one or more signals of the set of signals may be received at a rate dissimilar to the rate at which the IMD delivers electrical stimulation pulses. The processing circuitry may determine that the first group of signals is not indicative of volitional movement of the tongue of the patient, and may determine that the second group is indicative of volitional movement of the tongue of the patient.
  • a CMAP signal may include one or more peaks and/or valleys that greatly exceed the normal amplitude of peaks and/or valleys in a non-evoked EMG signal.
  • the CMAP signal may include a peak that is much larger than a peak of the EMG signal.
  • processing circuitry of the IMD may determine whether one or more signals are indicative of volitional movement of the tongue based on whether the one or more peaks of the one or more signals exceed a threshold. For example, the processing circuitry may determine that a signal peak exceeds a peak threshold, and in response, determine that the signal containing the signal peak is an evoked signal that is not indicative of volitional movement of the tongue of the patient.
  • the processing circuitry may determine that a peak does not exceed the peak threshold, and in response, determine that the signal containing the peak is not an evoked signal and therefore indicative of volitional movement of the tongue of the patient.
  • the IMD may include multiple different peak thresholds in memory.
  • the IMD may include a nonvolitional peak threshold and a volitional peak threshold, wherein the nonvolitional peak threshold is higher than the volitional peak threshold.
  • the processing circuitry may determine that signals with peaks exceeding the nonvolitional peak threshold are not indicative of volitional movement of the tongue, whereas processing circuitry may determine that peaks below the volitional peak threshold are indicative of volitional movement of the tongue.
  • An evoked CMAP signal may be considered as including two components: an artifact component and non-artifact component.
  • the processing circuitry may determine that a signal that contains an artifact component is an evoked signal, and therefore not indicative of volitional movement of the tongue of the patient.
  • processing circuitry may analyze any number of features of one or more received signals in order to determine whether the one or more signals are indicative of volitional movement of the tongue of the patient. For example, processing circuitry may compare the mean of one or more signals to a mean threshold, a median of one or more signals to a median threshold, a valley of one or more signals to a valley threshold, etc. Processing circuitry may also analyze any derivation of signal features, e.g., a standard deviation or variance of the signal.
  • one or more methods may be used, for example as described in “Automatic Detection of Stimulation Artifacts to Isolate Volitional from Evoked EMG Activity” by Ana Caroline C. de Sousa et. al., IFAC- PapersOnLine, 51-27 (2016) 282-287 (available at https://doi.Org/10.1016/j.ifacol.2018.l l.628).
  • a change in the CMAP signal may be indicative of volitional movement of the tongue of the patient.
  • CMAP signals may be regularly evoked from patient tissue due to the OSA therapy.
  • the IMD may receive a first series of regular CMAP signals and a second series of regular CMAP signals in response to the same OSA therapy.
  • the series of CMAP signals may be “regular” in that they are received in regular time increments in response to the OSA therapy.
  • the first series of CMAP signals may be received at a different time than the second series of CMAP signals.
  • the series of CMAP signals evoked due to OSA therapy while the tongue is in the first position may all be similar to one another (e.g., have the same or substantially similar signal profiles on a graph).
  • the signal profile of the series of CMAP signals evoked due to OSA therapy while the tongue is in the second position may have different signal profiles than the CMAP signals evoked in the first position.
  • a substantial change in the signal profile of the CMAP signal may be indicative of a changed position of the tongue of the patient.
  • the processing circuitry of the IMD may determine whether a first series of CMAP signals differ substantially from a second series of CMAP signals.
  • the signal profile for a first series of CMAP signals may be represented by first CMAP signal 602 (shown in FIG. 6)
  • the signal profile for a second series of CMAP signals may be represented by second CMAP signal 604 (shown in FIG. 6).
  • the processing circuitry may determine, for each point along one of the signal profiles, whether the corresponding point along the other signal profile differs by more than a threshold percentage.
  • the processing circuitry may determine whether a pair of corresponding points along CMAP signals 602 and 604 differ by a threshold value (e.g., a threshold mV value).
  • a threshold value e.g., a threshold mV value
  • Example 1 A system including a memory and processing circuitry coupled to the memory, the processing circuitry configured to: receive, via one or more electrodes, one or more signals from patient tissue; determine whether the one or more signals from the patient tissue are indicative of volitional movement of a tongue of a patient; and control therapy of an implantable medical device (IMD) configured to deliver therapy for sleep apnea based on the determination.
  • IMD implantable medical device
  • Example 2 The system of example 1, wherein to determine whether the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient, the processing circuitry is configured to: compare the one or more signals to one or more sets of reference signal data stored in a database in the memory known to correspond to volitional movement; and determine, based at least in part on the comparison, whether the one or more signals are indicative of volitional movement of the tongue of the patient.
  • Example 3 The system of any of example 1 or 2, wherein to determine whether the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient, the processing circuitry is configured to determine that the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient, and wherein to control therapy of the IMD, the processing circuitry is configured to change, in response to determining that the one or more signals are indicative of the volitional movement, a therapy state of the IMD from an ON therapy state to an OFF therapy state, wherein in the OFF therapy state, the IMD is configured to not deliver electrical stimulation pulses for treating sleep apnea.
  • Example 4 The system of any of examples 1-3, wherein to determine whether the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient, the processing circuitry is further configured to determine that the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient, and wherein to control therapy of the IMD, the processing circuitry is configured to change, in response to determining that the one or more signals are indicative of the volitional movement, a therapy state of the IMD from an ON therapy state to a DELAY therapy state, wherein in the DELAY therapy state, the IMD is configured to wait a period of time before delivering electrical stimulation pulses for treating sleep apnea to patient tissue.
  • Example 5 The system of any of examples 1-4, further including an external device, wherein to control therapy of the IMD, the processing circuitry is further configured to: receive an instruction from the external device to change a therapy state of the IMD to an ON therapy state; and change, in response to receiving the instruction, the therapy state to a DELAY therapy state, wherein in the DELAY therapy state, the IMD is configured to wait a period of time before transitioning to the ON therapy state.
  • Example 6 The system of any of examples 1-5, further including stimulation circuitry, wherein to receive the one or more signals from the patient tissue, the processing circuitry is configured to: deliver, via stimulation circuitry of the IMD, one or more electrical stimulation pulses to the patient tissue; and sense, via the one or more electrodes, one or more evoked signals from the patient tissue evoked in response to the delivery of the one or more electrical stimulation pulses.
  • Example 7 The system of any of examples 1-6, further including stimulation circuitry, wherein to control therapy of the IMD, the processing circuitry is configured to provide OSA therapy to a tongue of the patient when the IMD is in an ON therapy state by causing the stimulation circuitry to deliver a therapeutic stimulation signal to patient tissue.
  • Example 8 The system of any of examples 1-7, wherein to determine whether the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient, the processing circuitry is configured to determine that no signals have been received from patient tissue over a time period; and wherein to control therapy of the IMD, the processing circuitry is configured to change, at least partially in response to determining that no signals have been received over the time period, a therapy state of the IMD from an OFF therapy state to an ON therapy state, wherein, in the ON therapy state, the IMD is configured to provide OSA therapy to the patient tissue.
  • Example 9 The system of any of examples 1-8, further including an external device, wherein the one or more signals include a first set of one or more signals, wherein to control therapy of the IMD, the processing circuitry is configured to change a therapy state of the IMD to a CALIBRATION therapy state, wherein in the CALIBRATION therapy state, the processing circuitry is configured to display one or more sets of instructions on the external device instructing the patient to engage in one or more actions designed to elicit a second set of one or more signals from the patient tissue; wherein to receive the second set of signals from patient tissue, the processing circuitry is configured to sense, via the one or more electrodes, the second set of signals from the patient tissue corresponding to the one or more actions; and wherein to determine whether the first set of signals from the patient tissue are indicative of volitional movement of the tongue of the patient, the processing circuitry is configured to store, in a database in the memory, the second set of signals from the patient tissue as one or more sets of signal data with labels indicating the one or more sets
  • Example 10 The system of any of examples 1-9, wherein the one or more signals includes a first set of one or more signals from the patient tissue, and wherein the processing circuitry is configured to: receive, via the one or more electrodes, a second set of one or more signals from the patient tissue within a threshold amount of time after receiving the first set of one or more signals; and change, in response to sensing the second set within the threshold amount of time, a therapy state of the IMD to a SNOOZE therapy state, wherein in the SNOOZE therapy state, the processing circuitry does not sense for signals from the patient tissue for a period of time.
  • the processing circuitry is configured to: receive, via the one or more electrodes, a second set of one or more signals from the patient tissue within a threshold amount of time after receiving the first set of one or more signals; and change, in response to sensing the second set within the threshold amount of time, a therapy state of the IMD to a SNOOZE therapy state, wherein in the SNOOZE therapy state, the processing circuitry
  • Example 11 The system of any of examples 1-10, wherein the one or more signals received from the patient tissue include one or more of a compound muscle action potential or an electromyography signal.
  • Example 12 The system of any of examples 1-11, wherein the processing circuitry is configured to: determine a time of day; and change a therapy state of the IMD at least in part based on the determined time of day.
  • Example 13 The system of any of examples 1-12, further including one or more leads implanted within a tongue of the patient, wherein the one or more leads includes the one or more electrodes and wherein the one or more electrodes are disposed in close proximity to a hypoglossal nerve of the patient.
  • Example 14 The system of any of examples 1-13, wherein to determine whether the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient, the processing circuitry is configured to: compare the one or more signals to one or more sets of reference signal data stored in a database in the memory known to correspond to one or more specific actions, wherein the one or more specific actions are stored in the database as corresponding to one or more control inputs; determine, based at least in part on the comparison, that the one or more signals satisfy a threshold similarity with a set of the one or more sets of reference signal data corresponding to a specific action of the one or more specific actions corresponding to a control input of the one or more control inputs; and control therapy of the IMD based on the control input corresponding to the specific action.
  • Example 15 A method including: receiving, via one or more electrodes, one or more signals from patient tissue; determining whether the one or more signals from the patient tissue are indicative of volitional movement of a tongue of the patient; and controlling therapy of an IMD configured to deliver therapy for sleep apnea based on the determination.
  • Example 16 The method of example 15, wherein determining whether the one or more signals from the patient tissue are indicative of volitional movement includes: comparing the one or more signals to one or more sets of reference signal data stored in a database in the memory known to correspond to volitional movement; and determining, based at least in part on the comparison, whether the one or more signals are indicative of volitional movement of the tongue of the patient.
  • Example 17 The method of any of example 15 or 16, wherein determining whether the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient includes determining that the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient, and wherein controlling therapy of the IMD includes changing, in response to determining that the one or more signals are indicative of the volitional movement, a therapy state of the IMD from an ON therapy state to an OFF therapy state, wherein in the OFF therapy state, the IMD is configured to not deliver electrical stimulation pulses for treating sleep apnea.
  • Example 18 The method of any of examples 15-16, wherein determining whether the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient includes determining that the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient, and wherein controlling therapy of the IMD includes changing, in response to determining that the one or more signals are indicative of the volitional movement, a therapy state of the IMD from an ON therapy state to a DELAY therapy state, wherein in the DELAY therapy state, the IMD is configured to wait a period of time before delivering electrical stimulation pulses for treating sleep apnea to patient tissue.
  • Example 19 The method of any of examples 15-17, wherein controlling therapy of the IMD includes: receiving an instruction from an external device to change a therapy state of the IMD to an ON therapy state; and changing, in response to receiving the instruction, the therapy state to a DELAY therapy state, wherein in the DELAY therapy state, the IMD is configured to wait a period of time before transitioning to the ON therapy state.
  • Example 20 The method of any of examples 15-18, wherein receiving the one or more signals from the patient tissue includes: delivering, via stimulation circuitry of the IMD, one or more electrical stimulation pulses to the patient tissue; and sensing, via the one or more electrodes, one or more evoked signals from the patient tissue evoked in response to the delivery of the one or more electrical stimulation pulses.
  • Example 21 The method of any of examples 15-19, wherein controlling therapy of the IMD includes providing OSA therapy to a tongue of the patient when the IMD is in an ON therapy state by causing stimulation circuitry of the IMD to deliver a therapeutic stimulation signal to patient tissue.
  • Example 22 The method of any of examples 15-20, wherein determining whether the one or more signals from the patient tissue are indicative of volitional movement of the tongue of the patient includes determining that no signals have been received from patient tissue over a time period; and wherein controlling therapy of the IMD includes changing, at least partially in response to determining that no signals have been received over the time period, a therapy state of the IMD from an OFF therapy state to an ON therapy state, wherein, in the ON therapy state, the IMD is configured to provide OSA therapy to the patient tissue.
  • Example 23 The method of any of examples 15-21, wherein the one or more signals include a first set of one or more signals, wherein controlling therapy of the IMD includes changing a therapy state of the IMD to a CALIBRATION therapy state, wherein in the CALIBRATION therapy state, the processing circuitry is configured to display one or more sets of instructions on an external device instructing the patient to engage in one or more actions designed to elicit a second set of one or more signals from the patient tissue; wherein receiving the second set of signals from patient tissue includes sensing, via the one or more electrodes, the second set of signals from the patient tissue corresponding to the one or more actions; and wherein determining whether the first set of signals from the patient tissue are indicative of volitional movement of the tongue of the patient includes storing, in a database in the memory, the second set of signals from the patient tissue as one or more sets of signal data with labels indicating the one or more sets of signal data are indicative of volitional patient movement.
  • Example 24 The method of any of examples 15-22, wherein the one or more signals includes a first set of one or more signals from the patient tissue, and wherein the method further includes: receiving, via the one or more electrodes, a second set of one or more signals from the patient tissue within a threshold amount of time after receiving the first set of one or more signals; and changing, in response to sensing the second set within the threshold amount of time, a therapy state of the IMD to a SNOOZE therapy state, wherein in the SNOOZE therapy state, the processing circuitry does not sense for signals from the patient tissue for a period of time.
  • Example 25 The method of any of examples 15-23, wherein the one or more signals received from the patient tissue include one or more of a compound muscle action potential or an electromyography signal.
  • Example 26 The method of any of examples 15-24, further including: determining a time of day; and changing a therapy state of the IMD at least in part based on the determined time of day.
  • Example 27 The method of any of examples 15-25, wherein the IMD includes one or more leads implanted within a tongue of the patient, wherein the one or more leads include the one or more electrodes and wherein the one or more electrodes are disposed in close proximity to a hypoglossal nerve of the patient.
  • Example 28 A computer-readable storage medium storing instructions thereon that when executed cause one or more processors to: receive, via one or more electrodes, one or more signals from patient tissue; determine whether the one or more signals from the patient tissue are indicative of volitional movement of a tongue of a patient; and control therapy of an implantable medical device (IMD) configured to deliver therapy for sleep apnea based on the determination.
  • IMD implantable medical device
  • the techniques of this disclosure may be implemented in a wide variety of computing devices, medical devices, or any combination thereof. Any of the described units, modules or components may be implemented together or separately as discrete but interoperable logic devices. Depiction of different features as modules or units is intended to highlight different functional aspects and does not necessarily imply that such modules or units must be realized by separate hardware or software components. Rather, functionality associated with one or more modules or units may be performed by separate hardware or software components, or integrated within common or separate hardware or software components.
  • the disclosure contemplates computer-readable storage media comprising instructions to cause a processor to perform any of the functions and techniques described herein.
  • the computer-readable storage media may take the example form of any volatile, non-volatile, magnetic, optical, or electrical media, such as a RAM, ROM, NVRAM, EEPROM, or flash memory that is tangible.
  • the computer-readable storage media may be referred to as non-transitory.
  • a server, client computing device, or any other computing device may also contain a more portable removable memory type to enable easy data transfer or offline data analysis.
  • processors including one or more microprocessors, DSPs, ASICs, FPGAs, or any other equivalent integrated, discrete logic circuitry, or other processing circuitry, as well as any combinations of such components, remote servers, remote client devices, or other devices.
  • processors including one or more microprocessors, DSPs, ASICs, FPGAs, or any other equivalent integrated, discrete logic circuitry, or other processing circuitry, as well as any combinations of such components, remote servers, remote client devices, or other devices.
  • processors or “processing circuitry” may generally refer to any of the foregoing logic circuitry, alone or in combination with other logic circuitry, or any other equivalent circuitry.
  • any of the described units, modules or components may be implemented together or separately as discrete but interoperable logic devices. Depiction of different features as modules or units is intended to highlight different functional aspects and does not necessarily imply that such modules or units must be realized by separate hardware or software components. Rather, functionality associated with one or more modules or units may be performed by separate hardware or software components, or integrated within common or separate hardware or software components.
  • any module described herein may include electrical circuitry configured to perform the features attributed to that particular module, such as fixed function processing circuitry, programmable processing circuitry, or combinations thereof.
  • the techniques described in this disclosure may also be embodied or encoded in an article of manufacture including a computer-readable storage medium encoded with instructions. Instructions embedded or encoded in an article of manufacture including a computer-readable storage medium encoded, may cause one or more programmable processors, or other processors, to implement one or more of the techniques described herein, such as when instructions included or encoded in the computer-readable storage medium are executed by the one or more processors.
  • Example computer-readable storage media may include random access memory (RAM), read only memory (ROM), programmable read only memory (PROM), erasable programmable read only memory (EPROM), electronically erasable programmable read only memory (EEPROM), flash memory, a hard disk, a compact disc ROM (CD-ROM), a floppy disk, a cassette, magnetic media, optical media, or any other computer readable storage devices or tangible computer readable media.
  • RAM random access memory
  • ROM read only memory
  • PROM programmable read only memory
  • EPROM erasable programmable read only memory
  • EEPROM electronically erasable programmable read only memory
  • flash memory a hard disk, a compact disc ROM (CD-ROM), a floppy disk, a cassette, magnetic media, optical media, or any other computer readable storage devices or tangible computer readable media.
  • the computer-readable storage medium may also be referred to as storage devices.
  • a computer-readable storage medium comprises non- transitory medium.
  • the term “non-transitory” may indicate that the storage medium is not embodied in a carrier wave or a propagated signal.
  • a non-transitory storage medium may store data that can, over time, change (e.g., in RAM or cache).

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Abstract

Système comprenant une mémoire et des circuits de traitement couplés à la mémoire. Les circuits de traitement sont configurés pour : recevoir, par l'intermédiaire d'une ou de plusieurs électrodes, un ou plusieurs signaux provenant d'un tissu d'un patient ; déterminer si le ou les signaux provenant du tissu du patient indiquent un mouvement volontaire d'une langue d'un patient ; et commander une thérapie d'un dispositif médical implantable (DMI) configuré pour administrer une thérapie pour l'apnée du sommeil sur la base de la détermination.
PCT/IB2024/052342 2023-03-14 2024-03-11 Commande de thérapie basée sur la détermination du mouvement de la langue Pending WO2024189520A1 (fr)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20200121492A1 (en) * 2018-10-18 2020-04-23 Huntington Medical Research Institutes Methods and devices for treating sleep apnea
WO2023028069A1 (fr) * 2021-08-24 2023-03-02 Avivomed, Inc. Stimulateur de nerf crânien à rétroaction thérapeutique

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20200121492A1 (en) * 2018-10-18 2020-04-23 Huntington Medical Research Institutes Methods and devices for treating sleep apnea
WO2023028069A1 (fr) * 2021-08-24 2023-03-02 Avivomed, Inc. Stimulateur de nerf crânien à rétroaction thérapeutique

Non-Patent Citations (2)

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Title
ANA CAROLINA C. DE SOUSA: "Automatic Detection of Stimulation Artifacts to Isolate Volitional from Evoked EMG Activity", IFAC-PAPERSONLINE - 16TH IFAC SYMPOSIUM ON CONTROL IN TRANSPORTATION SYSTEMS CTS 2021 LILLE, FRANCE, 8-10 JUNE 2021, vol. 51, no. 27, 1 January 2018 (2018-01-01), DE, pages 282 - 287, XP093160467, ISSN: 2405-8963, Retrieved from the Internet <URL:https://www.sciencedirect.com/science/article/pii/S2405896318333378/pdf?md5=be63345911b5e35221d8845c92aa1b76&pid=1-s2.0-S2405896318333378-main.pdf> [retrieved on 20240508], DOI: 10.1016/j.ifacol.2018.11.628 *
ANA CAROLINE C. DE SOUSA: "Automatic Detection of Stimulation Artifacts to Isolate Volitional from Evoked EMG Activity", IFAC-PAPERSONLINE, vol. 51-27, 2018, pages 282 - 287

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