Abstract:
Techniques, devices, and systems for isolating, by isolation circuitry connected to a power source, a voltage from the power source, receiving, by sensing circuitry, the isolated voltage, receiving, by the sensing circuitry, a reference voltage from an implantable reference electrode via a reference node, and sensing, by the sensing circuitry, the biomedical signal with two or more implantable sensing electrodes using the isolated voltage with respect to the reference voltage.
Abstract:
A magnetic resonance imaging (MRI) telemetry arrangement and process for a cochlear implant system are described. Electrode current is measured that is induced in a cochlear implant electrode lead during an MRI process performed on an implanted patient. An MRI telemetry signal for an external telemetry sensor is then output based on the measured electrode current.
Abstract:
Overvoltage protection circuitry configured to protect internal integrated circuits within an implantable device in the presence of a high voltage event such as defibrillation or electrocautery. The circuitry allows for an internal node to rise above the voltage level of the high voltage event to insure that an overvoltage protection element is triggered, even if the voltage level of the high voltage event is below the voltage trigger level of the overvoltage protection element.
Abstract:
An implantable medical device implements a special mode of operation, such as a mode of electrical stimulation therapy, during conditions where there may be an increased likelihood that a device reset will occur. The implantable medical device recovers from the device reset by copying values that specify the special mode and that are stored in a non-volatile memory to an operating memory. The special mode is implemented after the device reset has occurred by using the values copied to the operating memory. One version of the special mode is an MRI mode that allows the implantable medical device to safely operate during an MRI scan. The fields of the MRI scan may trigger a device reset, but the MRI mode values are copied from the non-volatile memory to the operating memory, and the MRI mode is implemented after the reset by using the values copied to the operating memory.
Abstract:
The present invention relates to an electronic system (10) of an implantable medical device, comprising at least one first circuit (20), at least one tracking means, which is configured such that radio frequency bursts and/or a gradient magnetic field of a magnetic resonance imaging apparatus can be tracked, and at least one synchronizing means, whereby the synchronizing means is configured such that based on the tracked radio frequency bursts and/or the gradient magnetic field the at least one first circuit (20) and/or the electronic system (10) as a whole is synchronized with the radio frequency bursts and/or the gradient magnetic field.
Abstract:
A device includes a housing configured to be implanted in a patient. The device also includes a first magnetic field direction sensor located at a first location within the housing and configured to generate a signal representative of a first direction of a magnetic field at the first location, a second magnetic field direction sensor located at a second location within the housing and configured to generate a signal representative of a second direction of the magnetic field at the second location, and a magnetic field strength sensor configured to generate a signal representative of a strength of the magnetic field. The device further includes a control module configured to identify a source of the magnetic field based on at least one of the signal representative of the strength of the magnetic field and the signals representative of the first and second directions of the magnetic field.
Abstract:
Medical lead bodies that are paired each include a braided conductive shield. The braided conductive shield of one lead body has a value for a physical parameter that differs from a value for the physical parameter of the second lead body. The difference in values of the physical parameter for the paired lead bodies results in a reduction in heating from exposure of the lead bodies to radiofrequency energy at electrodes associated with the lead bodies. The lead bodies may be paired by being implanted adjacently to one another. The lead bodies may be further paired by being coupled to a same distal body, such as a paddle containing the electrodes.
Abstract:
An implantable electrical stimulation system (500) includes a control module (504) electrically coupleable to a lead (502). The control module includes a housing (507), an electronic subassembly (530) disposed in the housing and a connector assembly (520) for receiving the lead. The connector assembly includes a port for receiving a proximal end of the lead. Connector contacts (528) are disposed in the connector assembly housing and electrically couple to the electronic subassembly. The connector contacts align with terminals (510) disposed on the lead to form an electrical connection between the connector contacts and the terminals when the proximal end of the lead is disposed in the port of the connector assembly. A disconnecting feature (580) includes a switch for electrically disabling, or at least significantly reducing, the electrical connection between the connector contacts and the electronic subassembly when the switch is opened.
Abstract:
An implantable medical device (IMD) may be configured into a sensing only mode in which the IMD does not delivery therapy. For example, the IMD may be configured to operate in a sensing only mode to reduce the undesirable effects that may be caused by external fields, such as those generated by an MRI device. However, there may be instances, such as a change in the patients condition, in which it may be desirable to transition from the sensing only mode to a pacing mode to provide therapy. In accordance with the techniques described herein, the IMD monitors signals on one or more leads coupled to the medical device while operating in the sensing only mode and transitions to a pacing mode in response to not detecting a minimum number of signals on the one or more leads.
Abstract:
An implantable control module for an electrical stimulation system includes an electronic subassembly disposed in a sealed conductive housing. A plurality of feedthrough pins extend through the sealed housing and couple connector contact of an external connector to the electronic subassembly. Each of the plurality of conductive pathways electrically couples a different one of the plurality of feedthrough pins to the electronic subassembly. A ground line electrically couples the electronic subassembly to the housing. A capacitive flex circuit is disposed in the housing and couples to each of the feed through pins. For each of the plurality of feedthrough pins the capacitive flex circuit includes a first conductive path electrically coupling the feedthrough pin to a corresponding conductive pathway of the plurality of conductive pathways, and a second conductive path electrically coupling the feedthrough pin to the ground pin.