206 results about "Bio impedance" patented technology

Systems and methods for discriminating and locating tissues within a body involve applying a waveform signal to tissue between two electrodes and measuring the electrical characteristics of the signal transmitted through the tissue. At least one of the electrodes is constrained in area so that localized electrical characteristics of the tissue are measured. Such localized electrical characteristics are determined over a portion of a body of the subject by using an array of electrodes or electrodes that can be moved over the body. A controller may implement the process and perform calculations on the measured data to identify tissue types and locations within the measured area, and to present results in graphical form. Results may be combined with other tissue imaging technologies and with image-guided systems.

The invented non-invasive vital signs monitor is in a flexible, nominally flat planar form having integral gel electrodes, a sticky-back rear surface, an internal flex circuit capable of sensing, recording and playing out several minutes of the most recently acquired ECG waveform data and a front surface that includes an outplay port. The invented non-invasive body composition ‘risk’ monitor includes a measurement device for monitoring one or more variables including body fluid mass, dehydration, respiratory rate, blood pressure, bio-impedance, cardiography such as cardiac output, and body conformation parameters. The risk monitor may be provided in a lightweight carrying case into which the vital signs monitor plugs. Thus the two monitors may be independent or they may be integrated into one portable, non-invasive device that can convey important patient data to / from a remote patient medical data center via wireless telemetry for oversight, treatment and possible intervention by a physician.

The invented non-invasive vital signs monitor is in a flexible, nominally flat planar form having integral gel electrodes, a sticky-back rear surface, an internal flex circuit capable of sensing, recording and playing out several minutes of the most recently acquired ECG waveform data and a front surface that includes an outplay port. The invented non-invasive body composition ‘risk’ monitor includes a measurement device for monitoring one or more variables including body fluid mass, dehydration, respiratory rate, blood pressure, bio-impedance, cardiography such as cardiac output, and body conformation parameters. The risk monitor may be provided in a lightweight carrying case into which the vital signs monitor plugs. Finally, a lightweight portable probe or transducer containing a transmissive or reflective electro-optical emitter and receptor in the infrared spectrum is fitted on a subject's finger or toe. Associated electronics energize and monitor the probe, detect cardio-rhythmic fluctuations therefrom, and process digital data over a prescribed window to produce a non-invasive, qualitative or quantitative measure of the subject's circulation. In accordance with one embodiment of the invention, a simple tri-color LED array is used to indicate the subject's circulation as being normal, reduced, or borderline. Thus the vital signs, bio-impedance, and circulation monitors may be independent or they may be integrated into one portable, non-invasive device that can concurrently monitor and locally display or remotely convey important patient data including circulation data to a local subject or physician or to / from a remote patient medical data center via wireless telemetry for oversight, treatment and possible intervention by a remote physician.

A behavior modification system includes a network of components that interact to collect various data and provide user feedback. The network may include a personal device, an Internet-enabled storage device and a hub capable of receiving communications from the personal device and communicating to the storage device. The personal device may include bio-impedance measurement circuitry, an accelerometer and a processor for determining energy expenditure based on data from the accelerometer(s). The system may include a smart hub capable of routing communications between various components within the system. The hub may include different transceivers for different communication protocols. The system may incorporate a low-power RF wake-up system. The system may include bio-impedance measurement circuitry that is reconfigurable to function as an alternative type of sensor. In other aspects, the present invention provides a method for measuring bio-resonance and a method for determining caloric intake from body composition and caloric expenditure.

A method and system for discriminating tissues in a subject, particularly for identifying nerve tissue, includes a processor, a waveform generator, a waveform electrode and a return electrode and an electrical property measuring device such as a volt meter. The electrodes are applied to the skin of the subject and an electrical waveform applied to the tissue via the electrodes. A series of electrical property measurements between the electrodes yield digital data that is used to determine coefficients of an approximating mathematical function, which is then used to derived electrical properties of the tissue. Derived electrical properties are then displayed on a display device.

The present invention relates to an apparatus and method for the non-invasive analysis of physiological attributes, such as heart rate, blood pressure, cardiac output, respiratory response, body composition, and blood chemistry analytes including glucose, lactate, hemoglobin, and oxygen saturation. Using a combination of multi-functioning disparate sensors, such as optical and electrical, improvements are made over existing physiological measurement devices and techniques. The special configuration of one or more multi-functional sensors is used to non-invasively measure multi-wavelength optical plus one or more of ECG, Bio-impedance, and RF-impedance spectroscopic data. This information is used to develop self-consistent, non-linear algorithm in order to derive the physiological attributes while compensating for various forms of interfering effects including motion artifacts, sensor attachment variability, device component variability, subject physical and physiology variability, and various interfering physiological attributes.

A method of determining an impedance of at least one lung of a patient having an implanted pacemaker that comprises first and second leads and a case, the method comprising: a) using the leads and the case to acquire at least a first and a second impedance measurement responsive to impedance of the patient's chest that are at least partially independent; and b) using the impedance measurements to determine the impedance of at least one of the lungs substantially independently of impedance of the other lung.

An active implantable medical device, in particular a pacemaker, defibrillator or cardioveter of the multisite type, including a circuit for measuring intercardiac impedance. Electrodes are placed in at least one ventricular site and one atrial site, and are connected to a circuit for the collection of cardiac signals, to detect a depolarization potential, as well as to a stimulation circuit, to apply stimulation pluses to at least some of the aforementioned sites. The measurement of a trans-pulmonary bio-impedance is obtained by injecting a current from an injection circuit (16) between the case (18) of the device and a first atrial (RA-) (or ventricular) site, and measuring a differential potential (20) between the case (18) and a point of measurement located in a second atrial (RA+) (or ventricular) site using a collection circuit. Switches are selectively operable to isolate the case (18) from the current injection and measurement of potential circuits, and to connect them to a common reference potential site, atrial or ventricular (LV-), which is distinct from the sites (RA-,RA+) to which are also connected these circuits, so as to allow a measurement of intracardiac impedance from the signal delivered by the differential potential measuring circuit. The switching is obtained by connections to an electric ground, operating independently of the current injection circuit and the differential potential measuring circuit.

Bio-impedance may be used for navigation systems to chronically implant pacing and defibrillation leads in the heart using a non-fluoroscopic position sensing unit (PSU). Such a system requires that a conductive material, such as a retractable helical tip-electrode, be exposed during implantation. Since the tip is retracted during implantation, this disclosure provides a modified distal portion employing at least one aperture (or “window”) for fluid exposure of the helix-electrode and a deployable internal sleeve for covering the aperture(s) when the helix-electrode is extended.

The disclosure describes a wearable, low-cost and low-power Electrical Impedance Tomography system for gesture recognition. The system measures cross-sectional bio-impedance using electrodes on wearers' skin. Using all-pairs measurements, the interior impedance distribution is recovered, which is then fed to a hand gesture classifier. This system also solves the problem of poor accuracy of gesture recognition often observed with other gesture recognition approaches.

Implantable medical devices and techniques are implemented that use bio-impedance to measure aspects of patient physiology. A signal separation method is performed at least in part in an implantable device. The method involves detecting a plurality of impedance signals using a plurality of implantable electrodes coupled to the implantable device. The method further involves separating one or more signals from the plurality of impedance signals using a signal separation technique, such as an algorithm-based separation technique.

A method of treating tissue is provided, including positioning a portion of a catheter in proximity to cardiac tissue; measuring an impedance value with the catheter; determining a respiratory rate based at least in part on the measured impedance value; and thermally treating the cardiac tissue with the catheter.

A method of measuring of an electrical bio-impedance, the method being characterized in that a symmetrical bipolar pulse-form periodical excitation signal (electrical current or voltage) is applied to the input (11) of the bio-object (1), a corresponding reaction of the bio-object to the mentioned excitation signal is measured from the output (12), which is connected to the input (201) of the synchronous detector (200). A symmetrical bipolar pulse-form periodical signal is also applied to the reference input (202) of the synchronous detector (200), whereby both pulse-form signals are shortened by the predetermined time interval in each half period of the signal, said time intervals being different for the excitation and reference signals. The proposed method ensures an increased accuracy of the impedance analysis by decreasing the influence of the higher harmonics in the spectra of the excitation and reference signals of the synchronous detectors to the measurement result. The use of the rectangular signals ensures that the device for implementing of the proposed method has a simple design and low power consumption.

A passive element is provided to facilitate passive detection of analytes, such as analytes, using an electromagnetic probe beam. The probe beam may be provided by a radar and / or lidar system. In one example, a passive element comprises a reference dipole and a detection dipole, the detection dipole having an associated analyte-sensitive element, such as a chemoresistive or bioresistive element. When the analyte-sensitive element is in a modified conducting state due to the presence of an analyte, the detection cross section is modified whereas a reference cross section is substantially unchanged by the presence of the analyte. A passive element may comprise a frequency selective surface, for example including a frequency-selective surface (FSS) embedded in a dielectric layer and using an analyte-sensitive impedance layer to modify the electromagnetic absorption properties, allowing analyte detection.

A real-time decision-support system predicts hemorrhagic shock of a patient by analysis of electrocardiogram (ECG) signals and transcranial Doppler (TCD) signals from the patient. These signals are subject to signal decomposition using Discrete Wavelet Transform (DWT) to sets of wavelet coefficients and selecting significant signal features. Machine learning is applied to the significant features to evaluate and classify hypovolemia severity based on the input ECG and TCD signals from the patient. The classification of blood loss severity is displayed in real-time. An extension of the decision-support system integrates Arterial Blood Pressure (ABP) signals and thoracic electrical bio-impedance (DZT) signals with the ECG and TCD signals from the patient to evaluate severity of hypovolemia.

The invention belongs to the technical field of medical instruments, and particularly relates to a miniature multi-sensing technology based multi-parameter dynamic monitoring and recording device for penile erection states. The device is medical auxiliary monitoring equipment which combines a dynamic penile erection state sensing monitoring technology and a continuous data recording method and dynamically monitors change of multiple indexes such as biological impedance, penile position angles, axial penile pressure, penile blood flow and the like in the penile erection states. The monitor comprises a physiological parameter acquisition module, an embedded master control module as well as accessories such as a lead, a battery, an elastic fiber sleeve and the like. All the function modules coordinate with one another to work under the unified control of the master control module and acquire, process and record physiological information capable of reflecting various function states in penises of monitored patients in real time. The device can realize non-invasive, reliable and continuous monitoring of the penile erection states of the patients in real and natural sleep states and provide powerful and objective data reference for clinical assessment of male erectile dysfunctions.

A portable device for measuring a bioimpedance-related property of tissue includes a plurality of electrodes arranged in a pattern on a surface and associated software for measuring bio-impedance related data of localized regions of tissue and calculate health-related parameters based on the measured data. These calculated parameters may be representative of muscular health of the localized tissue region.

An active implantable medical device having a plurality of connection terminals able to be connected to electrodes placed in at least three distinct respective sites in a myocardium; circuits for measuring an intracardiac bio-impedance, comprising circuits for injecting a current and circuits for collecting a voltage at respective poles of a configuration of said connection terminals, and circuits able to deliver at an output a dynamic impedance signal that is a function of the injected current and the collected voltage; and circuits for evaluating an intracardiac volume, receiving at in input the impedance signal and delivering at an output a dynamic value of volume representing an instantaneous absolute value of intracardiac volume.

The present invention relates to a method for determining the posture of a patient. The method comprises the steps of: initiating (50, 52) a patient posture determining session by performing an electrical bio-impedance measurement session in at least one of a number of different electrode configurations in order to measure an impedance value for the at least one configuration; obtaining reference impedance values (54) stored in advance for the at least one configuration and for at least one potential posture of the patient; comparing (54) the measured impedance value for the at least one configuration with corresponding stored reference impedance values for at least one potential posture of the patient; and determining (56) the present posture of the patient by using results from the comparison between measured impedance values and the stored reference impedance values. Furthermore, the invention relates to a medical device for determining the posture of a patient and a computer readable medium comprising instructions for bringing a computer to perform the inventive method.

An active implantable medical device having a plurality of connection terminals able to be connected to electrodes placed in at least three distinct respective sites in a myocardium; circuits for measuring an intracardiac bio-impedance, comprising circuits for injecting a current and circuits for collecting a voltage at respective poles of a configuration of said connection terminals, and circuits able to deliver at an output a dynamic impedance signal that is a function of the injected current and the collected voltage; and circuits for evaluating an intracardiac volume, receiving at in input the impedance signal and delivering at an output a dynamic value of volume representing an instantaneous absolute value of intracardiac volume.

Embodiments of synchronous detection circuits and methods are provided for extracting magnitude and phase information from a waveform. One embodiment of a synchronous detection circuit includes a driver circuit, an analog-to-digital converter (ADC) and a controller. The driver circuit is configured to supply an input waveform at an input frequency to a load. The ADC is coupled to receive an output waveform from the load, and configured for generating four digital samples, each spaced 90° apart, for every period of the output waveform. The controller is configured for setting an oversampling rate (OSR) of the ADC, so that the ADC generates an integer number, M, of sub-samples for each digital sample generated by the ADC, where the integer number, M, of sub-samples is inversely proportional to the input frequency of the input waveform. The controller is further configured to use the digital samples generated by the ADC to extract magnitude and phase information from the output waveform.

Electrodes for a bio-impedance measuring device or a body composition monitor, the electrodes being integral with or being attached to a surface of at least one device belonging to a group of electronic and / or non-electronic devices used in the preparation of a dialysis treatment or during dialysis, in particular during peritoneal dialysis, the group preferably consisting of organizers of a continuous ambulatory peritoneal dialysis system (CAPD), automated peritoneal dialysis devices, automated peritoneal dialysis-cyclers (APD-Cycler), bioelectrical impedance analyzers (BIA), body composition monitors (BCM), hand-held electrodes holders for the electrodes, and dialysis apparatuses. Devices and methods used during dialysis are also described.