Random Or Pseudorandom Pulse Pattern Patents (Class 607/73)
  • Patent number: 10646400
    Abstract: An electrotherapy device capable of gradually increasing the intensity of stimulation is provided with a voltage regulation circuit, which is electrically connected to a DC power supply unit, a control unit, and a pulse output circuit respectively, and can regulate the voltage output to the pulse output circuit according to a control signal received from the control unit, in order for the waveforms of the electrical pulses output from the pulse output circuit to vary in modulated intensity, modulated waveforms, modulated frequencies and modulated rest period durations, and for the output current output from the pulse output circuit to each electrode pad to gradually increase from a low value to a predetermined value. The electrotherapy device can thus stimulate corresponding acupoints on a human body with gradually increasing intensity and thereby simulate the forces and tactile sensations of a typical manual massage on those acupoints by hand.
    Type: Grant
    Filed: February 13, 2018
    Date of Patent: May 12, 2020
    Inventor: Hoi Ming Michael Ho
  • Patent number: 9517344
    Abstract: Systems and methods for selecting low-power, effective signal delivery parameters for an implanted pulse generator are disclosed. A representative system includes a signal generator and a computer-readable medium that, for first and second signals, increases and decreases an amplitude of the signal over multiple steps from a baseline amplitude at which the patient has a baseline response. At individual step increases and decreases, the system receives a pain score based on the patient's response. The instructions compare the pain scores for the two signals and determine one of the signals for additional therapy to the patient, based on the pain scores and an expected energy consumption of the signals.
    Type: Grant
    Filed: March 1, 2016
    Date of Patent: December 13, 2016
    Assignee: Nevro Corporation
    Inventor: Kerry Bradley
  • Patent number: 9002472
    Abstract: Methods, apparatuses, and software for operating such apparatuses, for neuromodulation in a live mammalian subject, such as a human patient, provide for applying electrical energy to a target site in the nervous system of the subject using a signal comprising a series of pulses, wherein the inter-pulse intervals are varied using the output of a deterministic, non-linear, dynamical system comprising one or more system control parameters. In certain embodiments, the target site may be a site in the brain involved in generalized CNS (central nervous system) arousal. The dynamical system may be capable of exhibiting chaotic behavior.
    Type: Grant
    Filed: February 26, 2010
    Date of Patent: April 7, 2015
    Assignees: Intelect Medical, Inc., The Rockefeller University
    Inventors: Scott Kokones, Bradford Curtis Fowler, Donald Pfaff, Amy Wells Quinkert
  • Patent number: 8923981
    Abstract: Systems of and methods for stimulation of neurological tissue that may generate stimulation trains with temporal patterns of stimulation is shown and disclosed herein. The temporal patterns of stimulation may include intervals between electrical pulses (the inter-pulse intervals) that change or vary over time. Compared to conventional continuous, high rate pulse trains having regular (i.e., constant) inter-pulse intervals, the non-regular (i.e., not constant) pulse patterns or trains that embody features of the invention may provide a lower average frequency.
    Type: Grant
    Filed: February 19, 2013
    Date of Patent: December 30, 2014
    Assignee: Duke University
    Inventors: Warren M. Grill, Jr., David T. Brocker
  • Publication number: 20140364923
    Abstract: This device comprises a generator producing bursts (Si) of N pulses (I) of VNS stimulation generated in succession during respective periods of activity (TON) separated by intermediate periods of inactivity (TOFF) during which no stimulation is issued. Stochastic modulation means control the delivery of the bursts of each of the N pulses of each VNS burst by selective inhibition or not, of the generation of each of said VNS pulses depending on the result of a respective randomization. The number of VNS pulses of each burst is thus randomly varying, and thus the VNS stimulation energy of this burst and the interval between successive pulses, which counteract the appearance of a physiological compensation loop.
    Type: Application
    Filed: June 10, 2014
    Publication date: December 11, 2014
    Inventors: Thierry LEGAY, Hervè BLUMSTEIN
  • Patent number: 8874229
    Abstract: A method comprises applying a first open-loop electrical signal to a neural structure at a first rate. The method also comprises applying a closed-loop electrical signal to the neural structure in response to an event detection, thus causing an overall rate at which electrical stimulation is applied to the neural structure to exceed the first rate. The method further comprises applying a second open-loop electrical signal to a neural structure at a second rate that is lower than the first rate, thus causing the overall rate to be reduced to the first rate.
    Type: Grant
    Filed: April 28, 2010
    Date of Patent: October 28, 2014
    Assignee: Cyberonics, Inc.
    Inventor: John C. Colborn
  • Patent number: 8812115
    Abstract: A method and neurostimulator for providing therapy to a patient is provided. In one technique, electrical background energy is conveyed to a first tissue region of the patient in accordance with stochastic parameter, thereby modulating the excitability of the first tissue region, and electrical stimulation energy is conveyed to the first tissue region when its excitability is modulated. In one example, the stimulation energy may be conveyed to a second tissue region of the patient, thereby therapeutically stimulating the second tissue region. In this case, the excitability of the first tissue region is decreased, thereby reducing any adverse effect that the conveyed stimulation energy has on the first tissue region. As another example, the conveyed stimulation energy stimulates the first tissue region, in which case, the excitability of the first tissue region may be increased, thereby enhancing the stimulation of the first tissue region by the conveyed stimulation energy.
    Type: Grant
    Filed: July 10, 2009
    Date of Patent: August 19, 2014
    Assignee: Boston Scientific Neuromodulation Corporation
    Inventor: Dongchul Lee
  • Patent number: 8798755
    Abstract: Systems and methods for stimulation of neurological tissue and generation stimulation trains with temporal patterns of stimulation, in which the interval between electrical pulses (the inter-pulse intervals) changes or varies over time. The features of the stimulation trains may be selected and arranged algorithmically to by clinical trial. These stimulation trains are generated to target a specific neurological disorder, by arranging sets of features which reduce symptoms of that neurological disorder into a pattern which is effective at reducing those symptoms while maintaining or reducing power consumption versus regular stimulation signals. Compared to conventional continuous, high rate pulse trains having regular (i.e., constant) inter-pulse intervals, the non-regular (i.e., not constant) pulse patterns or trains that embody features of the invention provide increased efficacy and/or a lower than average frequency.
    Type: Grant
    Filed: October 11, 2012
    Date of Patent: August 5, 2014
    Assignee: Duke University
    Inventors: Warren M Grill, David T Brocker, Merrill J Birdno
  • Publication number: 20140180364
    Abstract: A method, system, and apparatus for providing a stimulation signal comprising a variable ramping portion using an implantable medical device (IMD). The first electrical comprises a first ramping portion. The first ramping portion comprises a first parameter and having a first value. The first electrical signal is applied to a target location of the patient's body. A second electrical signal comprising a second ramping portion is generated. The second ramping portion comprises the first parameter having a second value that is different from the first value. The second electrical signal is applied to a target location of the patient's body.
    Type: Application
    Filed: February 27, 2014
    Publication date: June 26, 2014
    Applicant: CYBERONICS, INC.
    Inventor: Randolph K. ARMSTRONG
  • Patent number: 8750984
    Abstract: A device for stimulation via electric and magnetic fields is provided. The autonomic/vegetative nervous system can be controlled by signals in the frequency ranges of 0.05 to 0.15 Hz and 0.15 to 0.30 Hz, respectively. By addition of characteristic sinusoidal oscillations between the head and a peripheral area with the corresponding low-frequency sympathetic or parasympathetic control frequency as base oscillation and with application-typical EEG frequencies and higher-frequency sinusoidal oscillations in the range of ca. 250 to 1500 Hz, characteristic stimulation programs are established. These are applied by field applicators in the upper body area and in the lower body. The associated mat applicators distribute field energy. The field applicator is equipped with a combination of a magnetic-field-generating coil arrangement and an electrode arrangement generating the electric field. The electrode generating the electric field can at the same time be designed as a magnetic-field-generating coil.
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: June 10, 2014
    Assignee: Actegy Ltd.
    Inventors: Stewart Penny, Manfred Krauss, Roland Fischer, Werner Schmidt, Mario Mobius
  • Patent number: 8694118
    Abstract: A method, system, and apparatus for providing a stimulation signal comprising a variable ramping portion using an implantable medical device (IMD). The first electrical comprises a first ramping portion. The first ramping portion comprises a first parameter selected from the group consisting of an amplitude, a rate of change of the amplitude, a time period of a rate of change of the amplitude, a pulse width, a rate of change of the pulse width, a time period of a rate of change of the pulse width, a frequency, a rate of change of the frequency, a time period of a rate of change of the frequency, and a duration of a time period of the ramping portion, the first parameter having a first value. The first electrical signal is applied to a target location of the patient's body. A second electrical signal comprising a second ramping portion is generated. The second ramping portion comprises the first parameter having a second value that is different from the first value.
    Type: Grant
    Filed: October 28, 2005
    Date of Patent: April 8, 2014
    Assignee: Cyberonics, Inc.
    Inventor: Randolph K. Armstrong
  • Patent number: 8682441
    Abstract: The method and system described herein relate to stimulating nerve tissue using a pulse generator. A stimulus is created that comprises a signal that is produced from a frequency spectrum having a power spectral density per unit of bandwidth proportional to 1/f?, wherein ? is excludes 0. The stimulus is provided from the pulse generator to at least one stimulation lead; and applied to nerve tissue via one or several electrodes.
    Type: Grant
    Filed: August 30, 2011
    Date of Patent: March 25, 2014
    Assignee: Advanced Neurostimulation Systems, Inc.
    Inventor: Dirk De Ridder
  • Publication number: 20140031905
    Abstract: A method for stimulating nerve tissue of an organism includes a step of electrically connecting an electrical signal source to at least a first nerve. The method also includes applying a periodically repeating burst pulse signal pattern to the first nerve. The burst pulse signal pattern has a pattern frequency defining a frequency of repetition of the burst pulse signal pattern and a pattern duty cycle defining a first time period of the burst pulse signal pattern, the burst pulse signal pattern having a plurality of pulses, the pulses having a frequency within the pattern that exceeds the pattern frequency by at least an order of magnitude.
    Type: Application
    Filed: July 12, 2013
    Publication date: January 30, 2014
    Inventors: Pedro P. Irazoqui, Matthew Peter Ward, Kurt Yuqin Qing
  • Patent number: 8478422
    Abstract: The present invention is generally directed to a method for regulating cellular and tissue physiology, a device for practicing the method, and a process for fabricating the device. In general the process comprises the steps of providing at least one patterned electrode, providing a least one cell, placing the at least one electrode in electrical communication with the at least one cell, and applying a voltage to the electrode thereby delivering an effective amount of a patterned electric field or current thus regulating the physiology and/or growth of the at least one cell.
    Type: Grant
    Filed: September 21, 2006
    Date of Patent: July 2, 2013
    Assignees: The Ohio State University, The Regents of the University of Michigan
    Inventors: Arthur J. Epstein, Stephen E. Feinberg, Derek J. Hansford, Yanyin Yang
  • Patent number: 8447405
    Abstract: Systems and methods for stimulation of neurological tissue generate stimulation trains with temporal patterns of stimulation, in which the interval between electrical pulses (the inter-pulse intervals) changes or varies over time. Compared to conventional continuous, high rate pulse trains having regular (i.e., constant) inter-pulse intervals, the non-regular (i.e., not constant) pulse patterns or trains that embody features of the invention provide a lower average frequency.
    Type: Grant
    Filed: October 5, 2009
    Date of Patent: May 21, 2013
    Assignee: Duke University
    Inventors: Warren M Grill, Alan D Dorval, II
  • Patent number: 8355789
    Abstract: Method and apparatus providing asynchronous neural stimulation pseudo-randomly varying at least one of a plurality of stimulation parameters. Neural stimulation may be monitored and compared with a target. Parameters may be varied to more closely match stimulation target. A range for at least one parameter may be established and the parameter varied within the range. A finite sequence of values within the range may be generated or selected. An average of the finite sequence of values may approximate the stimulation target.
    Type: Grant
    Filed: April 28, 2006
    Date of Patent: January 15, 2013
    Assignee: Medtronic, Inc.
    Inventors: Jon Werder, Jonathon E. Giftakis
  • Patent number: 8265767
    Abstract: A hearing prosthesis configured for delivery of stochastic stimulation to a recipient. The hearing prosthesis comprises a sound pickup component configured to receive a sound signal having at least one pitch; a stochastic stimulation generator configured to generate a stochastic sequence of stimulation pulses having first and second inter-pulse intervals distributed stochastically throughout the sequence within controlled limits, the first inter-pulse interval based on the at least one pitch; and at least one stimulation channel to deliver the sequence of electrical stimulation pulses to the recipient.
    Type: Grant
    Filed: March 13, 2009
    Date of Patent: September 11, 2012
    Assignee: Cochlear Limited
    Inventor: Sean Lineaweaver
  • Patent number: 8265761
    Abstract: A method of reducing muscle pain in a person by removably attaching an electrode to each ear on a person's head and connecting the electrodes to receive a modified pulse signal from a computer or a digital port. The signal from the computer or the digital port are rectangular voltage pulses of “1s” and “0s” at varying frequencies. The rectangular pulse signal from the computer or digital port is modified to have at least the leading square corner of each rectangular voltage pulse rounded before it is sent to the electrodes. A method of randomizing the stimulus at about 100 Hz for improved sleep and an alternate method of randomizing stimuli for the neurological reduction of perceived pain and a similar method for reducing pain output from a muscle and its associated tissues directly.
    Type: Grant
    Filed: August 16, 2009
    Date of Patent: September 11, 2012
    Inventor: David R Siever
  • Patent number: 7949403
    Abstract: An electrical stimulation system and method for the treatment of neurological disorders is disclosed. In a preferred embodiment, the electrical stimulation system includes channels of electrodes positioned in electrical contact with tissue of a neuromuscular target body region of a patient to provide pattered neuromuscular stimulation to the patient's musculature. In addition, at least one electrode from a channel is positioned in electrical contact with a tissue of the motor control region of the brain. A series of patterned electrical pulses are then applied to the patient through the channels to provide peripheral neuromuscular stimulation, and a direct current is applied transcranially to the brain. Various exemplary embodiments of the invention are disclosed.
    Type: Grant
    Filed: February 27, 2007
    Date of Patent: May 24, 2011
    Assignee: Accelerated Care Plus Corp.
    Inventors: Francis X. Palermo, J. Chris Castel
  • Publication number: 20110087309
    Abstract: Techniques for varying stimulus parameters used in neural stimulation to improve therapy efficacy, minimize energy consumption, minimize undesired side effects, and minimize loss of therapeutic effectiveness due to physiologic tolerance to stimulation. Neural stimulation is provided having a stimulation amplitude, a stimulation frequency, a stimulation pulse duration, an electrode-firing pattern, and a set of electrode-firing-polarity conditions. At least one of the stimulation parameters is pseudo-randomly varied. A second stimulation parameter is changed based upon having pseudo-randomly varied the first stimulation parameter and based upon a predetermined relationship specifying how changes in the first parameter affect desirable values for the second parameter.
    Type: Application
    Filed: December 16, 2010
    Publication date: April 14, 2011
    Applicant: MEDTRONIC, INC.
    Inventor: Paul H. Stypulkowski
  • Patent number: 7869882
    Abstract: According to one aspect, an electrical stimulation system for treating tinnitus is provided. The system includes an electrical stimulation lead adapted for implantation into the person's skull for electrical stimulation of target brain tissue located in the person's temporal lobe. The lead includes one or more electrodes adapted to be positioned near the target brain tissue and to deliver electrical stimulation energy to the target brain tissue. The system also includes a stimulation source operable to generate signals for transmission to the electrodes of the lead to cause the electrodes to deliver electrical stimulation energy to the target brain tissue located in the person's temporal lobe to reduce tinnitus effects.
    Type: Grant
    Filed: November 9, 2007
    Date of Patent: January 11, 2011
    Assignee: Advanced Neuromodulation Systems, Inc.
    Inventor: Dirk DeRidder
  • Patent number: 7689284
    Abstract: A pseudounipolar stimulator lead for anchoring to a digestive organ is provided.
    Type: Grant
    Filed: October 12, 2005
    Date of Patent: March 30, 2010
    Assignee: IntraPace, Inc.
    Inventors: Mir A. Imran, Jacob Anthiah Bashyam
  • Patent number: 7419474
    Abstract: A method for producing a non-linearly varying therapeutic signal for therapy wherein a string of randomly or nonlinearly varying data increments the input to a mathematical function such as incrementing the phase angle of a sine function to produce a non linearly varying signal for application as therapy. This method also includes inserting upward chirps and sequencing different therapeutic signals to create a composite signal.
    Type: Grant
    Filed: January 3, 2006
    Date of Patent: September 2, 2008
    Inventor: Richard Lee
  • Patent number: 7050856
    Abstract: Techniques for varying stimulus parameters used in neural stimulation to improve therapy efficacy, minimize energy consumption, minimize undesired side effects, and minimize loss of therapeutic effectiveness due to physiologic tolerance to stimulation. Neural stimulation is provided having a stimulation amplitude, a stimulation frequency, a stimulation pulse duration, an electrode-firing pattern, and a set of electrode-firing-polarity conditions. At least one of the stimulation parameters is pseudo-randomly varied. A second stimulation parameter is changed based upon having pseudo-randomly varied the first stimulation parameter and based upon a predetermined relationship specifying how changes in the first parameter affect desirable values for the second parameter.
    Type: Grant
    Filed: January 11, 2002
    Date of Patent: May 23, 2006
    Assignee: Medtronic, Inc.
    Inventor: Paul H. Stypulkowski
  • Patent number: 6862481
    Abstract: A pulse generating apparatus has two like output channels that apply generated pulse signals of selected characteristics to two electrodes attached to a strap, each electrode receiving a different signal. The strap is attached to the foot so that the electrodes are positioned to stimulate with an electrical signal the abductor hallucis muscle of the foot to correct an imbalance due to overpowering by the adductor hallucis muscle. The signal strengthens the abductor hallucis muscle so that eventually it regains strength sufficient to counter balance the imbalance effect of the stronger adductor hallucis muscle and alleviate the bunion condition. The electrical signal generator generates signals that are pulses that are adjustable in frequency, modulation, pulse width and amplitude with modified square waves.
    Type: Grant
    Filed: November 20, 2000
    Date of Patent: March 1, 2005
    Inventor: Bassem M. Demian
  • Patent number: 6842646
    Abstract: An apparatus (22) for applying a therapeutic signal (31) to the scalp (32) of a subject (20) includes a first electrode (26) for massaging the scalp (32) and second electrode (30) in contact with the subject (20) and located remote from the first electrode (26). The therapeutic signal (31), passing between the first and second electrodes (26, 30) through the scalp (32), serves to loosen connective tissue and improve blood circulation in the scalp. The apparatus (22) includes digital waveform generators (54) for generating harmonically non-related resultant signals (96). The resultant signals (96) are combined to form the therapeutic signal (31) exhibiting a pseudorandom signal characteristic.
    Type: Grant
    Filed: November 15, 2002
    Date of Patent: January 11, 2005
    Assignee: Sono-Therapy Institute, Inc.
    Inventors: Sylvester A. Pitzen, Stephen M. Monnig
  • Patent number: 6671557
    Abstract: A system and method for providing percutaneous electrical nerve stimulation therapy to a patient renders the therapy effective for a large patient population and a broad range of patient conditions. The method includes the steps of inserting an electrode into the patient and applying an electrical signal between the electrode and the patient's body at a plurality of frequencies that automatically vary over the range of frequencies. The range of frequencies may have a minimum frequency of at most about 20 Hz and a maximum frequency of at least about 40 Hz. In addition, the electrical signal may be compensated for changes in frequency. The compensation may be in the form of amplitude adjustment or pulse with adjustment to provide effective signal energy over the entire range of applied frequencies.
    Type: Grant
    Filed: October 10, 2000
    Date of Patent: December 30, 2003
    Assignee: Meagan Medical, Inc.
    Inventor: Brad Gliner
  • Patent number: 6618625
    Abstract: An apparatus and method for treating viral infections delivers electrical stimulation to the skin or mucosa of a patient. The electrical stimulation is applied as a series of electrical pulses having different electrical characteristics. The apparatus may include a housing having at least two electrodes supplied with both AC and DC voltage, and powered by a battery. The electrodes are designed so as to maximize contact with the patient.
    Type: Grant
    Filed: November 29, 2000
    Date of Patent: September 9, 2003
    Inventor: Leon M. Silverstone
  • Publication number: 20030135248
    Abstract: Techniques for varying stimulus parameters used in neural stimulation to improve therapy efficacy, minimize energy consumption, minimize undesired side effects, and minimize loss of therapeutic effectiveness due to physiologic tolerance to stimulation. Neural stimulation is provided having a stimulation amplitude, a stimulation frequency, a stimulation pulse duration, an electrode-firing pattern, and a set of electrode-firing-polarity conditions. At least one of the stimulation parameters is pseudo-randomly varied. A second stimulation parameter is changed based upon having pseudo-randomly varied the first stimulation parameter and based upon a predetermined relationship specifying how changes in the first parameter affect desirable values for the second parameter.
    Type: Application
    Filed: January 11, 2002
    Publication date: July 17, 2003
    Applicant: Medtronic, Inc.
    Inventor: Paul H. Stypulkowski
  • Patent number: 6526319
    Abstract: A living body stimulating apparatus for obtaining extensive therapeutic effects as well as soft feel of stimulation. Rectangular wave pulses output at a preset recurring frequency are subjected to pulse width modulation. Thus, the recurrence of a rectangular wave pulse group (S) which includes a plurality of higher frequency signal components than the rectangular wave pulses is imparted to a human body through electrodes (24). As a human body has a capacitive property, the higher frequency the signal component has, the lower impedance it will result in. As a result, the waveform of the rectangular wave pulse group (S) is distorted as a whole, thus providing softer feel of stimulation as compared with rectangular wave pulses of the same current and frequency. In addition, due to the higher frequency signals components being included, more extensive therapeutic effects can be expected.
    Type: Grant
    Filed: February 22, 2001
    Date of Patent: February 25, 2003
    Inventor: Tatsuyuki Kobayashi
  • Patent number: 6213934
    Abstract: Non-invasive quantitative in-vivo electromagnetic evaluation of bone is performed by subjecting bone to an electrical excitation waveform supplied to a single magnetic field coil near the skin of a bony member, and involving a repetitive finite duration signal consisting of plural frequencies that are in the range 0 Hz-200 MHz. Signal-processing of a bone-current response signal and a bone-voltage response signal is operative to sequentially average the most recently received given number of successive bone-current and bone-voltage response signals to obtain an averaged per-pulse bone-current signal and an averaged per-pulse bone-voltage signal, and to produce their associated Fourier transforms. These Fourier transforms are further processed to obtain the inductively determined frequency-dependent bone-admittance function.
    Type: Grant
    Filed: April 30, 1998
    Date of Patent: April 10, 2001
    Assignee: Hyper3D Corp.
    Inventors: Bruno Bianco, Alessandro Chiabrera, Jonathan J. Kaufman
  • Patent number: 5836994
    Abstract: A method and apparatus for providing electrical stimulation of the gastrointestinal tract. The apparatus features an implantable pulse generator which may be coupled to the gastric system through one or more medical electrical leads. In the preferred embodiment the leads couple to the circular layer of the stomach. The pulse generator preferably features sensors for sensing gastric electrical activity, and in particular, whether peristaltic contractions are occurring. In particular two sensors are featured. The first sensor senses low frequency gastrointestinal electrical activity between the frequency of 0.017-0.25 Hz and the second sensor senses intrinsic gastrointestinal electrical activity between the frequency of 100-300 Hz, which occurs upon normal peristaltic contractions. The second sensor only senses for a preset period after low frequency gastrointestinal electrical activity has been sensed by the first sensor.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: November 17, 1998
    Assignee: Medtronic, Inc.
    Inventor: Ivan Bourgeois
  • Patent number: 5792189
    Abstract: Method and apparatus are provided for cardiac defibrillation using a waveform with a dominant frequency near that of a fibrillating heart. The defibrillator includes electrical generating means for producing a waveform having a dominant frequency within a range of 2 Hz-20 Hz. The waveform provides low level electrical shock to a fibrillating heart, thereby causing defibrillation. The waveform, which can comprise a Rossler-type chaotic waveform or a sinusoidal waveform, preferably has a dominant frequency near the frequency of fibrillation of the fibrillating heart.
    Type: Grant
    Filed: April 4, 1997
    Date of Patent: August 11, 1998
    Assignee: The Research Foundation of State University of New York
    Inventors: Richard A. Gray, Jose Jalife
  • Patent number: 5792212
    Abstract: There is provided a measurement system for measuring signals evoked in response to stimulus pulses applied to a nerve, muscle or like physiological portion of a patient. The measurement system is characterized by delivering stimulus pulses at randomly generated intervals, and enabling the sense circuitry to track the timing of the stimulus pulse generation so as to aid in discriminating the evoked response pattern from surrounding noise. Specifically, after each stimulus pulse a delay is timed out for a time corresponding to the expected latency between the delivered pulse and the arrival of the evoked response at another location. The delay signal is then used to initiate time out of a window which controls operation of the sensing circuit for a window duration corresponding to when the evoked response pattern is appearing. Limiting the sensing operation to the window duration enables tracking of the response pattern, and minimizes power consumption.
    Type: Grant
    Filed: March 7, 1997
    Date of Patent: August 11, 1998
    Assignee: Medtronic, Inc.
    Inventor: Koen J. Weijand
  • Patent number: 5755749
    Abstract: A method for controlling changes in stimulation of every sort and kind including electrical stimulation, utilizes a three-dimensional 1/f fluctuation. The method is a change control method for controlling changes in stimulation to an object using a three-dimensional 1/f fluctuation and includes the steps of causing changes based upon 1/f fluctuation periods in the X-Z plane of a X-Y-Z space, causing changes based upon 1/f fluctuation periods in the X-Y plane of the space, superposing the caused changes of the previous steps, and applying the superposed caused changes to the object. This makes it possible to realize a low-frequency device free of problems attributable to the tolerance in neural response. A recording medium used to store the change control method, and a change control device using a three-dimensional 1/f fluctuation are also disclosed. Changes based on 1/f fluctuation periods in the X-Z plane and changes based on 1/f fluctuation periods in the X-Y plane are superposed on each other.
    Type: Grant
    Filed: August 1, 1996
    Date of Patent: May 26, 1998
    Assignee: Toyo Sangyo Co., Ltd.
    Inventor: Kazuhito Sakano
  • Patent number: 5456690
    Abstract: The present invention provides a system and method for delivering a defibrillation waveform which is a fractal or multifractal pulse sequence. In one embodiment of the invention, a plurality of monophasic rectangular or truncated exponential pulses are delivered with fractal timing. Each subsequent pulse in the sequence has a lower voltage than the preceding pulse and the pulses have equal duration. This fractal pulse sequence is generated in response to a sensed arrhythmia and it is delivered using conventional leads to a patient's heart. A predetermined fractal pulse sequence is stored in programmable memory and may be modified by a patient's physician.
    Type: Grant
    Filed: October 14, 1993
    Date of Patent: October 10, 1995
    Assignee: Ventritex, Inc.
    Inventor: Minn Duong-Van