摘要:
An implantable medical device (IMD) includes a detector for detecting the presence of x-ray radiation, where the presence of x-ray radiation is detected in response to the strength of the x-ray radiation exceeding a first threshold. In one embodiment, the IMD includes a processor for adjusting a cardiac stimulation rate IMD in response to determining that the strength of the detected x-ray radiation exceeds a second threshold. The second pre-selected x-ray radiation threshold is greater than the first pre-selected x-ray radiation threshold. In another embodiment, the implantable device includes a detector for detecting the presence of any amount x-ray radiation and a processor for adjusting a stimulation rate provided by the IMD in response to detected x-ray radiation to reduce the chance of over-sampling artifacts or inappropriate therapy delivery.
摘要:
According to the invention methods and structures for determining whether impingement of x-ray radiation upon potentially vulnerable discrete components, circuits and/or circuit pathways of an implantable medical device (IMD) causes modifications or damage thereto. The invention includes structures for deflecting impingement of x-ray radiation from said potentially vulnerable components, circuits and/or circuit pathways. The x-ray radiation can be generated by various imaging modalities or unknown sources. Myriad IMDs can utilize the teaching of the present invention, including for example, a pacemaker, a drug delivery pump, a nerve stimulation device, a muscle stimulation device, an implantable cardioverter-defibrillator, a subcutaneous defibrillator, a deep brain stimulator or the like.
摘要:
An implantable medical device (IMD) includes a detector for detecting the presence of x-ray radiation, where the presence of x-ray radiation is detected in response to the strength of the x-ray radiation exceeding a first threshold. In one embodiment, the IMD includes a processor for adjusting a cardiac stimulation rate IMD in response to determining that the strength of the detected x-ray radiation exceeds a second threshold. The second pre-selected x-ray radiation threshold is greater than the first pre-selected x-ray radiation threshold. In another embodiment, the implantable device includes a detector for detecting the presence of any amount x-ray radiation and a processor for adjusting a stimulation rate provided by the IMD in response to detected x-ray radiation to reduce the chance of over-sampling artifacts or inappropriate therapy delivery.
摘要:
An implantable medical device (IMD) includes a detector for detecting the presence of x-ray radiation, where the presence of x-ray radiation is detected in response to the strength of the x-ray radiation exceeding a first threshold. In one embodiment, the IMD includes a processor for adjusting a cardiac stimulation rate IMD in response to determining that the strength of the detected x-ray radiation exceeds a second threshold. The second pre-selected x-ray radiation threshold is greater than the first pre-selected x-ray radiation threshold. In another embodiment, the implantable device includes a detector for detecting the presence of any amount x-ray radiation and a processor for adjusting a stimulation rate provided by the IMD in response to detected x-ray radiation to reduce the chance of over-sampling artifacts or inappropriate therapy delivery.
摘要:
The invention relates to medical devices such as pacemakers, pulse generators, cardioverter-defibrillators and the like and more particularly relates to modular and reconfigurable medical system platforms and methods of designing, testing, controlling and implementing diverse therapies, diagnostics, physiologic sensors and related instrumentation using said medical system platforms. Methods, systems and devices provide a new design platform for implantable and external medical devices such as pacemakers, defibrillators, neurostimulators, heart monitors, etc. A real-time, highly flexible system of software and hardware modules enables both prototypes and products to respond to patient and customer needs with greater design and manufacturing efficiency. Certain embodiments integrate a general-purpose processor with interface circuitry to provide a standard platform for implementing new and conventional therapies with software models rather than custom circuitry. The platform described may be used as a simulation environment, development and test platform and/or may be used as architecture for building new medical devices.
摘要:
A signal measuring system for use with an Implantable Medical Device (IMD) is provided for measuring physiologic signals having a relatively large effective dynamic range. In one embodiment, the system includes a High-Pass Filter (HPF), an Analog-to-Digital Converter (ADC), a Decimation Filter (DF), and a Compensation Filter (CF). The HPF receives an input signal that includes both the baseline wander imposed on a physiological signal. According to one aspect of the invention, the HPF attenuates low frequency components of the input signal, including a portion of the frequency band within the desired output signal bandwidth. The ADC then oversamples the output signal of the HPF. The DF receives the output samples from the ADC and generates output samples at rate that is at least twice the maximum frequency of the desired output signal. The CF then amplifies the low frequency end of the DF output samples. The gain and cutoff frequency of the CF are selected to offset the HPF attenuation of those low frequency components of the input signal below the cutoff frequency of the HPF and above the minimum frequency of the desired output signal. In one embodiment, the DF and CF are implemented by a processing circuit executing programmed instructions. The processing circuit may be included within the IMD, or may be partially or fully implemented within a device that is external to the IMD.
摘要:
An electrical lead end cap includes a body defining a bore therein capable of receiving and retaining an end of an electrical lead and a connector capable of electrically coupling conductors leading to at least two electrodes. A method includes routing an electrical current induced in an electrical lead conductor disposed within body tissue to a plurality of electrodes, electrically coupled with the body tissue, via a circuit within an end cap attached to the electrical lead.
摘要:
Cyclic redundancy calculations are provided by operating on a data stream, e.g., a data stream in an implantable medical device, to perform a polynomial division thereon using one of a first cyclic redundancy code generator polynomial and a second cyclic redundancy code generator polynomial. The first cyclic redundancy code generator polynomial is a higher order polynomial than the second cyclic redundancy code generator polynomial and contains all terms of the second cyclic redundancy code generator polynomial. The polynomial division may be implemented using linear feedback shift register circuitry and circuitry to select between the use of the first or second cyclic redundancy code generator polynomial.
摘要:
An apparatus for communicating an electrical signal from a first portion of circuitry to a second, wherein there is no direct electrical contact between the two portions. In one embodiment, an EKG transmitter is disclosed which receives surface EKG signals from a patient, amplifies the EKG signals, modulates an oscillating carrier signal with the EKG signals, and transmits the resulting modulated signal across an optocoupled boundary. The modulated signal is then digitized directly, without demodulation, using phase progression digitization. The digitized information, from which the patient's EKG signal may be reconstructed, is then transmitted via a modem over conventional telephone lines. DC power drawn from the telephone line may be used directly to power the modem and phase progression digitizer, and may also be coupled via an isolating DC-to-DC transformer, to the frequency modulator and amplifier. For components of the patient's EKG signal which cannot be accurately re-created after modulation, separate, isolated circuitry can detect and process these components prior to modulation, and a separate optocoupled boundary can be established for conveying information about these components to the modem or digitizer.
摘要:
A radiation-based timer for use in an implantable medical device (IMD) includes a radiation source and a radiation detection circuit. The radiation source emits radiation particles during a process referred to as radioactive decay. The radiation detection circuit detects the radiation particles emitted during the decay process and tracks the number of radiation particles detected. When the number of radiation particles detected reaches a threshold value, a timer signal is generated. In this manner, the radiation-based timer generates a timer signal as a function of the radioactive decay of the radiation source. The timer signal may be used by one or more components of the IMD for any of a number of functions, including as a wakeup trigger for a communications and/or a sensor event.