Abstract:
A method is provided including delivering at least one electrical signal to tissue of a patient through an electrode. The method further includes assessing whether a net charge remains on the electrode a predetermined period of time after the delivery of the electrical signal. Systems for delivering such a signal, and assessing whether a net charge remains on the electrode providing the signal, are also provided.
Abstract:
An implantable medical device (IMD) may include a lead circuit including a first node configured to be coupled to a first lead that may be coupled to a first target tissue and including a second node configured to be coupled to a second lead that may be coupled to a second target tissue. The IMD may include an impedance unit that may determine at least one characteristic of coupled energy associated with the lead circuit, where the coupled energy may be produced by a source external to the IMD. The impedance unit may provide an impedance between the first node and the second node, where the impedance is selected based at least in part on a characteristic of the coupled energy. The impedance is selected to reduce the coupled energy or a negative effect associated with functionality of the IMD induced by the coupled energy.
Abstract:
A method and an apparatus for determining a time period remaining in a useful life of an energy storage device in an implantable medical device. The method may include measuring a voltage of the energy storage device to produce a measured voltage, and comparing the measured voltage to a transition voltage. While the measured voltage is greater than or equal to the transition voltage, the time period remaining in the energy storage device's useful life is approximated based upon a function of charge depleted. While the measured voltage is less than the transition voltage, the time period remaining in the energy storage device's useful life is approximated based upon a higher order polynomial function of the measured voltage. The transition voltage corresponds to a predetermined point on a energy storage device voltage depletion curve representing the voltage across the energy storage device over time.
Abstract:
A method sensing at least two physiological parameters and, for each of the at least two physiological parameters, generating a first series of signals representative of the physiological parameter sensed over a first time period, storing each of said first series of signals as a time sequence data stream, and determining when a physiological event has occurred in a patient. The method further comprises analyzing each of said time sequence data streams for a predetermined time interval preceding the occurrence of a physiological event to determine at least one marker as a predictor of the event, and again sensing the physiological parameters. Furthermore, the method comprises generating a second series of signals representative of the physiological parameter sensed, analyzing each of the second series of signals to determine whether the marker is present, and stimulating a cranial nerve when the marker is present in the second series of signals.
Abstract:
A method and an apparatus for determining a time period remaining in a useful life of an energy storage device in an implantable medical device. The method may include measuring a voltage of the energy storage device to produce a measured voltage, and comparing the measured voltage to a transition voltage. While the measured voltage is greater than or equal to the transition voltage, the time period remaining in the energy storage device's useful life is approximated based upon a function of charge depleted. While the measured voltage is less than the transition voltage, the time period remaining in the energy storage device's useful life is approximated based upon a higher order polynomial function of the measured voltage. The transition voltage corresponds to a predetermined point on a energy storage device voltage depletion curve representing the voltage across the energy storage device over time.
Abstract:
In one embodiment, an implantable neurostimulator comprises a pulse generator that generates an electrical pulse signal to stimulate a neural structure in a patient, a stimulation lead assembly coupled to the pulse generator for delivering the electrical pulse signal to the neural structure, a plurality of sensors coupled to the pulse generator, and sensor select logic. Each sensor is individually selectable and the sensor select logic selects any two or more of the plurality of sensors for sensing a voltage difference between the selected sensors. In other embodiments, two or more physiologic parameters are sensed. In yet another embodiment, a method comprises sensing intrinsic electrical activity on a person's nerve and stimulating the nerve based on the sensed intrinsic electrical activity of the nerve.
Abstract:
A method and an apparatus for projecting an end of service (EOS) and/or an elective replacement indication (ERI) of a component in an implantable device is provided. The method comprises measuring the measured voltage of the energy storage device, and determining whether the measured voltage is less than a transition voltage. When the measured voltage is less than the transition voltage, determining a time period remaining until an end of service of the energy storage device is based upon a function of the measured voltage. When the measured voltage is greater than or equal to the transition voltage, determining a time period remaining until an end of service of the energy storage device is based upon a function of the total charge depleted. The transition voltage is a voltage associated with the transition point of non-linearity in the battery voltage depletion curve.
Abstract:
A device comprises a stimulus generator comprising an instruction processor. The stimulus generator is configured to deliver stimuli to a biological tissue. The device also comprises a non-volatile memory for storing instructions directly executable by the instruction processor, the instructions controlling, at least in part, the operation of the device. The instruction processor generates an erase control signal to erase at least a segment of the non-volatile memory and a write control signal to write one or more new instructions to at least a segment of the non-volatile memory, thereby modifying the operation of the device.
Abstract:
In some embodiments, a method comprises providing an electrical signal to a nerve to evoke an action potential. The nerve thereby enters a refractory period in which the nerve is in a refractory state. The method further comprises, during the refractory period, providing an electrical signal to the nerve thereby altering the refractory period of the nerve or non-target tissues.
Abstract:
A method, system, and an apparatus for providing a therapy neurostimulation signal. The apparatus of the present invention includes a sealed housing being of a total volume of less than about 14.5 cc and a power supply contained within the sealed housing. The power supply includes a charge capacity of at least about 100 milliAmpHours. The apparatus also includes a controller to control an operation of the power supply and to provide an electrical neurostimulation signal for stimulating a portion of a neural tissue. The present invention also provides for implementing an interrupt-driven architecture into an implantable medical device.