A charging system for an Implantable Medical Device (IMD) is disclosed having a charging coil and one or more sense coils. The charging coil and one or more sense coils are preferably housed in a charging coil assembly coupled to an electronics module by a cable. The charging coil is preferably a wire winding, while the one or more sense coils are concentric with the charging coil and preferably formed in one or more traces of a circuit board. One or more voltages induced on the one or more sense coils can be used to determine whether the charging coil is (i) centered, (ii) not centered but not misaligned, or (iii) misaligned, with respect to the IMD being charged, which three conditions sequentially comprise lower coupling between the charging coil and the IMD. A charging algorithm is also disclosed that control charging dependent on these conditions.

An introducing device for locating a tissue region and deploying an electrode is shown and described. The introducing device may include an outer sheath. An inner sheath may be disposed within the outer sheath. The inner sheath may be configured to engage an implantable electrode. In an example, the inner sheath may comprise a stimulation probe having an uninsulated portion at or near a distal end of the delivery sheath. The outer sheath may be coupled to a power source or stimulation signal generating circuitry at a proximal end. A clinician may control application of the stimulation signal to a tissue region via the outer sheath.

A method and apparatus to detect anomalies in the conductors of leads attached to implantable medical devices based on the dynamical electrical changes these anomalies cause. In one embodiment, impedance is measured for weak input signals of different applied frequencies, and a conductor anomaly is detected based on differences in impedance measured at different frequencies. In another embodiment, a transient input signal is applied to the conductor, and an anomaly is identified based on parameters related to the time course of the voltage or current response, which is altered by anomaly-related changes in capacitance and inductance, even if resistance is unchanged. The method may be implemented in the implantable medical device or in a programmer used for testing leads.

Sense amplifier (amp) circuitry for an implantable stimulator device is disclosed useful for sensing neural responses or other voltages in a patient's tissue. The sense amp circuitry comprises a low-voltage and a high-voltage sense amp circuit, either of which may be selected based on an assessment of the magnitude of the voltage at either or both of the inputs connected to selected sensing electrodes. The assessed magnitude, as determined by monitoring circuitry, can be processed by an algorithm to select use of one of the sense amp circuits, selecting the low-voltage sense amp circuit when the magnitude(s) are lower, and the high-voltage sense amp circuit when the magnitude(s) are higher. Furthermore, DC offset compensation circuitry is disclosed to equate the DC levels of the inputs, which may only operate when the high-voltage sense amp is selected.

A method for determining and responding in real-time to an increased risk of death relating to a patient with epilepsy is provided. The method includes receiving cardiac data and determining a cardiac index based upon the cardiac data. The method includes determining an increased risk of death associated with epilepsy if the indices are extreme, issuing a warning of the increased risk of death and logging information related to the increased risk of death. Also presented is a second method for determining and responding in real-time to an increased risk of death relating to a patient with epilepsy comprising receiving at least one of arousal data, responsiveness data or awareness data and determining an arousal index, a responsiveness index or an awareness index, where the indices are based on arousal data, responsiveness data or awareness data respectively. The second method includes determining an increased risk of death related to epilepsy if indices are extreme values, issuing a warning of the increased risk of death and logging information related to the increased risk of death. A computer readable program storage device is also provided. Also provided is a method for receiving body data, determining a cardiac, an arousal, a responsiveness, or a kinetic index, determining an increased or increasing risk of death over a first time window relating to a patient with epilepsy and issuing a warning and logging relevant information.

The present invention changes the magnet-mode of an active implantable medical device (AIMD) using a static strip magnet comprising at least a first, second and third magnet. The electronic circuits of the AIMD have been programmed to register when the static strip magnet has been swiped across the AIMD so that when the magnetic field-detection sensor detects a defined north and south polarity sequence of the first, second and third magnets, the electronic circuits have been programmed to enter into magnet-mode with electrical stimulation therapy of the body tissue and/or electrical sensing of biological signals from the body tissue being suspended, maintained in a preset mode, or placed in a programmed mode.

The present invention relates to a system for communicating an operational state of a neuronal stimulation apparatus to an individual, comprising: means for determining the operational state of the apparatus; means for transmitting a first neuronal stimulation signal to a neuronal stimulation means of the individual adapted to elicit a sensory percept in the cortex of the individual, wherein the first neuronal stimulation signal is indicative of the operational state of the apparatus. The present invention further relates to a method and computer program comprising the steps of: determining the operational state of the apparatus, transmitting a neuronal stimulation signal to a neuronal stimulation means of the individual adapted to elicit a sensory percept in the cortex of the individual, wherein the first neuronal stimulation signal is indicative of the determined operational state of the apparatus.

One aspect of the present disclosure relates to a system that can prevent unintended signal components (noise) in an electric waveform that can be used for at least one of neural stimulation, block, and/or sensing. The system can include a signal generator to generate a waveform that includes an intended electric waveform and unintended noise. The system can also include a signal transformer device (e.g., a very long wire) comprising a first coil and a second coil. The first coil can be coupled to the signal generator to receive the waveform and remove the unintended noise from the electric waveform. The second coil can pass the electric waveform to an electrode. The second coil can be coupled to a capacitor that can prevent the waveform from developing noise at an electrode/electrolyte interface between an electrode and a nerve.

Systems and methods are described for denoising, or filtering out, unwanted noise or interference, from biological or physiological parameter signals or waveforms such as ECG signals caused by application of electromagnetic energy (e.g., electrical stimulation) in a vicinity of sensors configured to obtain the biological or physiological parameter signals.

Some embodiments relate to a device for generating stimulation signals, comprising: a stimulation delivery circuit; a first component to monitor charge delivered in at least one charge pulse via the stimulation delivery circuit; and a second component to ensure delivered charge substantially corresponds to charge of a charge pulse intended to be delivered by the stimulation delivery circuit. In some embodiments, the device may further comprise a charge setting circuit responsive to a charge pulse setting signal, such as a constant current of fixed pulse width, to set the charge of the charge pulse intended to be delivered.