Abstract:
A TANK filter is provided for a lead wire of an active medical device (AMD). The TANK filter includes a capacitor in parallel with an inductor. The parallel capacitor and inductor are placed in series with the lead wire of the AMD, wherein values of capacitance and inductance are selected such that the TANK filter is resonant at a selected frequency. The Q of the inductor may be relatively maximized and the Q of the capacitor may be relatively minimized to reduce the overall Q of the TANK filter to attenuate current flow through the lead wire along a range of selected frequencies. In a preferred form, the TANK filter is integrated into a TIP and/or RING electrode for an active implantable medical device.
Abstract:
One or more inductors and one or more capacitors are physically disposed relative to one another in series and are electrically connected to one another in parallel to form a bandstop filter. Chip inductors and chip capacitors having spaced apart conductive terminals are physically arranged in end-to-end abutting relation to minimize electrical potential between adjacent conductive terminals. The bandstop filter may be hermetically sealed within a biocompatible container for use with an implantable lead or electrode of a medical device. The values of the inductors and the capacitors are selected such that the bandstop filter is resonant at one or more selected frequencies, such as an MRI pulsed frequency.
Abstract:
An RFID tag is disposed within a hermetically sealed housing of an IMD. Low frequency RFID interrogators and tags are used, and the housing walls are made of materials, and/or are reduced in thickness, to facilitate RF communication between the RFID tag and an RFID reader/interrogator programmer. An RFID reader/interrogator may be used which has a limited transmit time and time-out period to avoid interference with the operation of the IMD.
Abstract:
A shielded three-terminal flat-through EMI/energy dissipating filter includes an active electrode plate through which a circuit current passes between a first terminal and a second terminal, a first shield plate on a first side of the active electrode plate, and a second shield plate on a second side of the active electrode plate opposite the first shield plate. The first and second shield plates are conductively coupled to a grounded third terminal. In preferred embodiments, the active electrode plate and the shield plates are at least partially disposed with a hybrid flat-through substrate that may include a flex cable section, a rigid cable section, or both.
Abstract:
An MRI-compatible electronic medical therapy system includes an active medical device connected to a plurality of electrodes. A multiplexer circuit includes at least one circuit protection device in electrical series with the electrodes and the medical device. The circuit protection device is adapted to permit current flow therethrough during normal medical device related therapy, but substantially prevent current flow therethrough in the presence of an induced electromagnetic field.
Abstract:
A TANK filter is provided for a lead wire of an active medical device (AMD). In a preferred form, the TANK filter is integrated into a TIP and/or RING electrode for an active implantable medical device. The TANK filter includes a capacitor in parallel with an inductor. The parallel capacitor and inductor are placed in series with the lead wire of the AMD, wherein values of capacitance and inductance are selected such that the TANK filter is resonant at a selected frequency to attenuate current flow through the lead wire along a range of selected frequencies. In a particularly preferred form, the TANK filter is manufactured using very low k materials of sufficient strength to handle forces applied thereto during installation and use.
Abstract:
One or more inductors and one or more capacitors are physically disposed relative to one another in series and are electrically connected to one another in parallel to form a bandstop filter. Chip inductors and chip capacitors having spaced apart conductive terminals are physically arranged in end-to-end abutting relation to minimize electrical potential between adjacent conductive terminals. The bandstop filter may be hermetically sealed within a biocompatible container for use with an implantable lead or electrode of a medical device. The values of the inductors and the capacitors are selected such that the bandstop filter is resonant at one or more selected frequencies, such as an MRI pulsed frequency.
Abstract:
A system for identifying active implantable medical devices (AIMD) and lead systems implanted in a patient using a radio frequency identification (RFID) tag having retrievable information relating to the AIMD, lead system and/or patient. The RFID tag may store information about the AIMD manufacturer, model number, serial number; lead wire system placement information and manufacturer information; MRI compatibility due to the incorporation of bandstop filters; patient information, and physician and/or hospital information and other relevant information. The RFID tag may be affixed or disposed within the AIMD or lead wires of the lead system, or surgically implanted within a patient adjacent to the AIMD or lead wire system.
Abstract:
An implantable radio frequency identification (RFID) tag includes a hermetically sealed biocompatible housing for an active implantable medical device (AIMD), an RFID microelectronics chip is disposed within the housing, and a biocompatible antenna extends from the RFID microelectronic chip and exteriorly of the housing. In a preferred form of the invention, the antenna is disposed within a header block of the AIMD, and the RFID chip is disposed within the AIMD housing.
Abstract:
An energy management system that facilitates the transfer of high frequency energy induced on an implanted lead or a leadwire includes an energy dissipating surface associated with the implanted lead or the leadwire, a diversion or diverter circuit associated with the energy dissipating surface, and at least one non-linear circuit element switch for diverting energy in the implanted lead or the leadwire through the diversion circuit to the energy dissipating surface. In alternate configurations, the switch may be disposed between the implanted lead or the leadwire and the diversion circuit, or disposed so that it electrically opens the implanted lead or the leadwire when diverting energy through the diversion circuit to the energy dissipating surface. The non-linear circuit element switch is typically a PIN diode. The diversion circuit may be either a high pass filter or a low pass filter.