Abstract: Methods and systems are disclosed for determining information about a position of an object within a distribution of materials having different complex conductivities. The method includes: (i) causing current to flow in the distribution; (ii) measuring an electrical signal at each of multiple locations in the distribution of materials in response to the current flow; (iii) providing spatial information about the distribution of materials with respect to a first reference frame, the spatial information indicative of regions of different complex conductivity in the distribution of materials; and (iv) determining the position of the object with respect to the spatial information about the distribution of materials based on measured electrical signals and the spatial information. In certain embodiments, the object is a catheter inserted into a patients heart cavity for cardiac mapping.

Abstract: Devices, systems, and methods for the localization of body lumen junctions and other intraluminal structure are disclosed.

Abstract: A device for monitoring a medical prosthesis and the human body includes a sensor for generating signals depending on surrounding stresses, a processor for processing the signals emitted by the sensor in order to convert the signals into data, a storage device for storing the data, a device for wireless transmission of the stored data, and a supply of electrical energy. The device is included in at least one casing, which is made of biocompatible material and has a device for fixing to a bone.

Abstract: A method and apparatus for inserting and monitoring the placement of a cannula tip within a peripheral vein of a human body where the cannula includes a sensor located at predetermined location and mounted on the cannula for sensing the biological material of the body to guide the insertion of the cannula tip into the vein and alerts to the withdrawal of the cannula tip from the vein in the body.

Abstract: Embodiments of devices and methods for evaluating tissue are disclosed. In one embodiment, a method for measuring a characteristic of a tissue may include passing a current through the tissue, measuring a signal corresponding to the voltage resulting from passing the current through the tissue, analyzing current passed through the tissue and resulting voltage to determine the electrical characteristics of the tissue; and analyzing the electrical characteristics of the tissue to determine a status of the tissue. Disposable sensors are disclosed.

Abstract: A method of monitoring amount of milk consumed by an infant being breastfed by a breast is disclosed. The method comprises: determining variations in electric capacitance of the breast during breastfeeding, and correlating the electric capacitance variations to an amount of milk consumed by the infant.

Abstract: Provided is a bioelectric signal measurement apparatus that obtains an alternate current component and a direct current component of a bioelectric signal. The apparatus includes a plurality of biomedical electrodes, a switch unit, a differential amplification unit, a bioelectric signal extraction unit, and a timing control unit. The plurality of biomedical electrodes are brought into contact with a living body surface and disposed separately from each other. The switch unit short-circuits the biomedical electrodes via a predetermined short-circuit resistance. The differential amplification unit is connected to the biomedical electrodes and amplifies a difference of electric signals therefrom. The bioelectric signal extraction unit extracts a bioelectric signal from an output signal of the differential amplification unit from the release of short-circuit between the biomedical electrodes to the next timing of short-circuiting.

Abstract: The present invention relates to a dry skin conductance electrode (12, 13) for contacting the skin (10) of a user. In order to provide a dry skin conductance electrode for long-term measurements which does not cause problems to the user while still providing a good signal level, the electrode (12, 13) comprises a material made of a noble metal doped with at least one dopant selected from the group consisting of hydrogen, lithium, sodium, potassium, rubidium, caesium and beryllium. The present invention also relates to a skin conductance sensor (20), a wristband (30) and an emotional event detection system.

Abstract: Timed sensing of collection of saliva in a liquid collection element of predetermined volumetric capacity may be used to determine salivary secretion rate, as may be indicative of state of euhydration or dehydration. Sensing of salivary flow rate may be further augmented by sensing concentration of at least one analyte in saliva (e.g., with an immunochromatographic assay performed in a lateral flow device) in order to determine a state of euhydration or dehydration. Production of saliva may be stimulated, and collected saliva may be analyzed to generate an analyte detection signal that indicative of presence and/or correlative of concentration of at least one analyte in the collected saliva to sense a state of euhydration or dehydration.

Abstract: Methods of using the device for conducting business transactions are also included. An impedance spectroscopy system for monitoring ischemic mucosal damage in hollow viscous organs comprises a sensor catheter and an impedance spectrometer for electrically driving the catheter to obtain a complex tissue impedance spectrum. Once the catheter is in place in one of a patient's hollow viscous organs, the impedance spectrometer obtains the complex impedance spectrum by causing two electrodes in the tip of the catheter to inject a current into the mucosal tissue at different frequencies, while two other electrodes measure the resulting voltages. A pattern recognition system is then used to analyze the complex impedance spectrum and to quantify the severity of the mucosal injury. Alternatively, the complex impedance spectrum can be appropriately plotted against the spectrum of normal tissue, allowing for a visual comparison by trained personnel.

Abstract: A method is provided for taking electrical impedance tomography measurements using multiple electrodes located at selected positions external to a volume of a subject body. Multiple orthogonal or near-orthogonal signals are introduced simultaneously by way of selected different electrodes and resultant predetermined responses (if any) at receiving electrodes are recorded or determined. The signals are encoded using the technique of code division multiplexing and received signals at each receiving electrode are cross-correlated with original signals to determine the contribution of each original signal to a composite received signal. The invention also relates to apparatus suitable for use in applying a method.

Abstract: A diagnostic Electrochemical Impedance Spectroscopy (EIS) procedure is applied to measure values of impedance-related parameters for one or more sensing electrodes. The parameters may include real impedance, imaginary impedance, impedance magnitude, and/or phase angle. The measured values of the impedance-related parameters are then used in performing sensor diagnostics, calculating a highly-reliable fused sensor glucose value based on signals from a plurality of redundant sensing electrodes, calibrating sensors, detecting interferents within close proximity of one or more sensing electrodes, and testing surface area characteristics of electroplated electrodes. Advantageously, impedance-related parameters can be defined that are substantially glucose-independent over specific ranges of frequencies. An Application Specific Integrated Circuit (ASIC) enables implementation of the EIS-based diagnostics, fusion algorithms, and other processes based on measurement of EIS-based parameters.

Abstract: A visceral fat measuring device is capable of simply and noninvasively measuring a visceral fat amount, by calculating the visceral fat amount based on trunk measurement information, impedance information of the entire trunk, and impedance information of a surface layer of the trunk. The visceral fat measuring device includes: a belt to be wound around the trunk that has a pressing member with electrodes E to be pressed onto the dorsal side of a person subjected to measurement; a pair of belt portions respectively fixed to both sides of the pressing member; a buckle for connecting the pair of belt portions; and indicators on the pair of belt portions to show distances from a reference position of the belt.

Abstract: In one aspect, a conductance catheter is provided for measuring the volume of a fluid. The conductance catheter comprises a series of electrodes and a circuit to compensate for variations in sensitivity of the electrodes in the catheter. In another aspect, a resistivity sensor is provided for determining the resistivity of a fluid. The sensor comprises a series of electrodes spaced such that the total distance between endmost electrodes does not exceed the diameter of the catheter deploying the sensor.

Abstract: Provided are an apparatus and a method for controlling human body contact of ground electrode, and a human body communication system using the same. The apparatus includes a resistance measuring unit for applying a predetermined voltage to a human body through a signal electrode, to measure a resistance value between the signal electrode and the ground electrode; a contact control unit for determining whether the ground electrode needs to contact the human body by using the measured resistance value, to provide control information associated with human body contact; and a contact performing unit for bringing the ground electrode into contact or out of contact with the human body according to the control information.

Abstract: Systems and methods can be used to determine activation information for points along a surface or selected region of interest. In one example, a computer-readable medium having computer-executable instructions for performing a method that includes computing a local activation vector based on relative timing among electrical signals corresponding to neighboring points of a plurality of points on a surface envelope. An activation time can be computed for each of the plurality of points as a function of corresponding local activation vectors.

Abstract: A problem related to a known eyewear-type electro-oculogram measuring apparatus which detects the eye potential using a pair of electrodes positioned outside both the eyes of a user and a pair of electrodes respectively positioned above and below one eye is that the two pairs of electrodes have had an impact on the skins of users, and discomfort on them. Besides, the electrodes are not excellent in design.

Abstract: An implantable device monitors and treats heart failure, pulmonary edema, and hemodynamic conditions and in some cases applies therapy. In one implementation, the implantable device applies a high-frequency multi-phasic pulse waveform over multiple-vectors through tissue. The waveform has a duration less than the charging time constant of electrode-electrolyte interfaces in vivo to reduce intrusiveness while increasing sensitivity and specificity for trending parameters. The waveform can be multiplexed over multiple vectors and the results cross-correlated or subjected to probabilistic analysis or thresholding schemata to stage heart failure or pulmonary edema. In one implementation, a fractionation morphology of a sensed impedance waveform is used to trend intracardiac pressure to stage heart failure and to regulate cardiac resynchronization therapy. The waveform also provides unintrusive electrode integrity checks and 3-D impedancegrams.

Abstract: A body fat measurement device includes a back area electrode group support unit including back area electrodes arranged to contact a back area of a measurement subject, a trunk area dimension measurement unit that detects the width and depth of a trunk area of the measurement subject, a position detection unit that detects a relative positional relationship between the back area electrode group support unit and the trunk area dimension measurement unit, an electrode selection unit that selects specific electrodes, placed in contact with the back area at an area that corresponds to the location of the navel of the measurement subject, from a plurality of electrodes included in a trunk area electrode group, based on the position information detected by the position detection unit, and a body impedance measurement unit that measures a body impedance of the measurement subject using the selected back area electrodes.

Abstract: This invention provides a system and method that allows a therapeutic device, such as an atrial fibrillation microwave ablation catheter or ablation tip to be guided to a remote location within a body cavity and then accurately immobilized on the tissue, including that of a moving organ, such as the heart.

Abstract: A body weight management device includes a measurement unit that measures a body impedance of a measurement subject, an impedance change detection unit that detects a temporal change in the measured body impedance, a variation amount computation unit that computes a body impedance variation amount in a unit period, and a determination unit that makes determination about a trend for subsequent changes in the measurement subject's body weight, using the body impedance variation in the unit period, and an output unit that outputs a result of the determination.

Abstract: A method and system for providing and aggregating bioelectrical signal data comprising: providing a stimulus configured to prompt an action in both a first user and a second user; at a first biosignal detector and a second biosignal detector, automatically collecting a first bioelectrical signal dataset from the first user as the first user performs the action and a second bioelectrical signal dataset from the second user as the second user performs the action; generating a first anonymized bioelectrical signal dataset from the first bioelectrical signal dataset and a second anonymized bioelectrical signal dataset from the second bioelectrical signal dataset; coupling the first and the second anonymized bioelectrical signal datasets with an action tag characterizing the action; and generating an analysis based upon the first the second anonymized bioelectrical signal datasets. An embodiment of the system comprises a biosignal detector and a processor configured to implement an embodiment of the method.

Abstract: A method for performing impedance measurements on a subject. The method includes, in a processing system, causing at least one electrical signal to be applied to the subject via first leads operatively connected to first electrodes provided on the subject, determining a first indication indicative of at least one first electrical signal measured via second leads operatively disconnected from second electrodes positioned on the subject, determining a second indication indicative of at least one second electrical signal measured via second leads operatively connected to second electrodes positioned on the subject, and determining from the indications and the at least one applied signal, at least one instantaneous impedance value.

Abstract: Seizure prediction systems and methods include measuring impedance and a potential within a brain of a patient to determine whether the brain is in a state indicative of a possibility of seizure. In some embodiments, at least one of the measured impedance or the measured potential may be used as a primary indication of the brain state indicative of a possibility of seizure. In one embodiment, if one of the measured impedance or the measured potential indicates a seizure, the other measurement (impedance or potential) may be used to validate whether the brain is in the state indicative of the possibility of seizure.

Abstract: An apparatus and processing method for assessing the electrical potential of cells in a living organism using a high-density sensor array having a density of at least about 9 electrodes per square inch for measuring the potential of the static and quasi-static electromagnetic fields of the group of cells proximal to each electrode, where the array can be placed overlying at least a portion of a surface of a living organism with substantially all of the electrodes electrically contactable with such surface, and the surface overlying a site containing cells of clinical interest.

Abstract: A method for analyzing the structure of an electrically conductive object, the method comprising the steps of: (i) obtaining electrical impedance data for the object over a range of frequencies; (ii) analyzing the obtained electrical impedance data using a transfer function of an assumed electrical model to determine a plurality of electrical impedance properties for the object; (iii) constructively combining selected ones of the determined plurality of electrical impedance properties to provide at least one parametric impedance value for the object; and (iii) imaging one or more of the determined parametric impedance values.

Abstract: The invention relates to the field of medical methods and equipment and in preferred embodiments to equipment and methods used in dentistry. In particular it relates to an apparatus for determining the location of the apex of a dental root canal wherein the apparatus allows the acquisition of more accurate data in a shorter time span.

Abstract: Advanced thoracic fluid monitoring capabilities using impedance are disclosed. An implantable medical device used for detection of changes in impedance in a patient can have means for measuring impedances of the patient in a supine position and in an upright position. Impedance differences can be generated which correspond to a diurnal delta value showing impedance differences between the supine and upright positions.

Abstract: Transducer-based systems and methods may be configured to display a graphical representation of a transducer-based device, the graphical representation including graphical elements corresponding to transducers of the transducer-based device, and also including between graphical elements respectively associated with a set of the transducers and respectively associated with a region of space between the transducers of the transducer-based device. Selection of graphical elements and/or between graphical elements can cause activation of the set of transducers associated with the selected elements. Transducer activation characteristics, such as initiation time, activation duration, activation sequence, and energy delivery characteristics, can vary based on numerous factors. Visual characteristics of graphical elements and between graphical elements can change based on an activation-status of the corresponding transducers.

Abstract: An abdomen width determiner determines an abdomen width of a subject. A shape index calculator calculates a shape index corresponding to a cross-sectional shape of an abdomen of the subject. An obesity evaluator evaluates whether an obesity degree of the subject is high or low. An obesity index calculator calculates an obesity index corresponding to the abdomen width using a first equation if the obesity evaluator evaluates that the obesity degree is low, and calculates an obesity index corresponding to the abdomen width and the shape index using a second equation different from the first equation if the obesity evaluator evaluates that the obesity degree is high.

Abstract: An index calculating section calculates an edema index value indicating the level of edema at a target portion of the body of a human subject, according to a bioelectric impedance of the target portion. An edema evaluation section identifies the edema stage corresponding to the edema index value calculated by the index calculating section from among a plurality of edema stages indicating the degrees of progress of edema symptoms. A result reporting section reports the edema stage identified by the edema evaluation section to the user.

Abstract: A planar coil arrangement (400) for a magnetic induction impedance measurement apparatus comprises an excitation coil (102) configured for generating a magnetic excitation field in an object, and a detection coil (404) configured for detecting a magnetic response field generated in response to the magnetic excitation field inducing a current in the object. In order to minimize an effect of the magnetic excitation field in the detection coil (404), the detection coil (404) is radially symmetrical shaped with respect to the excitation coil (102) and is arranged relative to the excitation coil (102) such that the magnetic excitation field is minimized in the detection coil (404).

Abstract: A method of measuring biological sample properties and a biological sample property measuring apparatus is provided. A method of measuring biological sample properties includes disposing a biomaterial to contact a sensing unit, detecting a radio frequency (RF) signal flowing through the sensing unit, and obtaining an RF property indicator of the biomaterial based on the detected RF signal.

Abstract: A system and method for detecting skin penetration. The system comprises an invasive component for penetrating the skin; a dummy electrode for making contact with the surface of the skin; at least one penetrating electrode disposed in the invasive component; and a Wheatstone bridge circuit; wherein a resistance across the dummy electrode and the penetrating electrode constitutes one of the resistive legs of the Wheatstone bridge circuit and skin penetration of the invasive component is detected based on a differential output voltage from the Wheatstone bridge circuit.

Abstract: The invention relates to the field of monitoring the hydration- and/or nutrition status of a patient by means of bioimpedance measurement values. This is based on the problem of also being able to determine by such measurements the body composition of an amputated person simply and individually. The invention is based on the observation that volume compartments can also be determined in amputated patients by means of bioimpedance measurements when reference is made to the body models, used and established hitherto for patients without amputations, without major adaptation. Merely the determining of a characteristic factor for the amputation is necessary, which can be determined by comparative measurements in advance. In particular exceptional situations of multiple amputations, it can be indicated to submit additional parameters to increase accuracy. Then the body models hitherto can also be further used for these cases.

Abstract: The invention relates to systems, devices, and methods for detecting infections associated with implantable medical devices. In an embodiment, the invention includes a method of detecting infection in a patient including measuring a physiological parameter using a chronically implanted sensor at a plurality of time points and evaluating the physiological parameter measurements to determine if infection is indicated. In an embodiment, the invention includes an implantable medical device including a first chronically implantable sensor configured to generate a first signal corresponding to a physiological parameter and a controller disposed within a housing, the controller configured to evaluate the first physiological parameter signal to determine if an infection is indicated. Other embodiments are also included herein.

Abstract: Portable electroviscerography systems are provided. Aspects of the systems include a body-associated receiver and an ingestible identifier unit, both of which are configured to detect visceral electrical signals. The system communicates with an extra-corporeal data processor configured to receive data from the body-associated receiver and generate and electroviscerogram from the received data. Also provided are methods of producing electroviscerograms using systems of the present invention.

Abstract: The invention relates to a system for the consolidation of a bone structure, comprising: a system for determining the quality of the bone structure, including a body, first and second electrodes arranged on the body, an electric generator for applying an electric current, a measurement device for measuring the electric current, and a processing device for determining an electrical magnitude representative of the aptitude of the bone structure for allowing electric current to pass therethrough and for delivering a signal representative of the quality of the bone structure, using the determined electrical magnitude; and a device selected from between an electrical stimulation device for applying an electric bone-growth stimulation and a fixation device for immobilising the bone structure.

Abstract: A hydration monitor includes a temperature sensor (20; 65) for measuring a subject's core body temperature and a processor (30). The processor is arranged to accept measurements from the temperature sensor (20; 65) and calculate a hydration level in dependence on changes in the measured core body temperature.

Abstract: A method of predicting the operating state of a curable bone cement composition includes determining the impedance of the bone cement composition. The impedance is used to predict a number of operating states of the bone cement composition including end-of-work time and setting time.

Abstract: Methods and systems for determining anatomical information based on signals measured by multiple, spatially distributed electrodes on a catheter are disclosed herein. In some examples, methods and systems disclosed herein can include causing current to flow between at least some of the electrodes, measuring an electrical signal at each of one or more measuring electrodes, and determining anatomical information based on the measured signals.

Abstract: A method of determining one or more physiological parameter of a patient by providing a plurality of implantable electrodes proximate a blood vessel of the patient, applying a measurement signal through the plurality of electrodes, the measurement signal having a known parameter, obtaining a resultant signal through the plurality of electrodes, the resultant signal having a resultant parameter, calculating vascular impedance based on the measurement signal and the resultant signal, and calculating a physiological parameter based on the vascular impedance. In some embodiments, the physiological parameter is utilized to modify a therapy signal controlling therapy delivered to the patient.

Abstract: The present invention provides methods and systems to periodically monitor the emotional state of a subject comprising the steps of: exposing the subject to a plurality of stimuli during a session; acquiring objective data from a plurality of monitoring sensors, wherein at least one sensor measures a physiological parameter; transferring the data to a database; and processing the data to extract objective information about the emotional state of the subject.

Abstract: The present invention relates to a catheter (6) comprising: a connector (65, 66) at a proximal side of the catheter for connecting the catheter to an external signal transmission/receiving unit (10) for transmitting and/or receiving signals, an electrode (63, 64) at a distal side of the catheter, and an electrical connection including an electrical wire (61, 62) for electrically connecting the electrode and the connector for the transmission of signals between the electrode and the connector, wherein the electrical connection has a high electrical resistance of at least 1 k?, in particular of at least 5 k?. Thus, the present invention provides a solution to prevent excessive heating during EP interventions under MR guidance by using highly resistive wires and or lumped resistors as connections within catheters.

Abstract: An implantable medical device has an impedance determiner for determining a cardiogenic impedance signal based on electric signals sensed by connected electrodes. A parameter calculator processes the impedance signal to calculate an impedance parameter representative of the cardiogenic impedance in connection with the diastolic phase of a heart cycle. This parameter is then employed by the device for monitoring acute decompensated heart failure status of a subject.

Abstract: A health data generation system has a measuring apparatus and a user terminal. The measuring apparatus transmits to the user terminal function type information indicating function of the measuring apparatus. The user terminal selects a desired function based on the received function type information and transmits the selected function as function designation information to measuring apparatus. The measuring apparatus transmits to the user terminal parameter specifying information designating the types of parameters necessary for performing the function specified by the function designation information. The user terminal prompts a user to input individual data to the parameters and registers the individual data together with the function designation information as registration information R.

Abstract: An apparatus for medical diagnosis and/or treatment is provided. The apparatus includes a flexible substrate, an intermediate bus disposed on the flexible substrate, and a plurality of sensing elements disposed on the flexible substrate and coupled to the intermediate bus. The plurality of sensing elements and intermediate bus are disposed on the flexible substrate such that the sensing elements are disposed at areas of minimal strain of the flexible substrate.

Abstract: A system and method for generating an electrophysiological map are provided. The system includes an electronic control unit (ECU) configured to receive a signal generated by an electrode disposed at a position on an external surface of the body and indicative of electric potential. The ECU is further configured to identify a surface boundary of an object of interest within the body using an image of the object. The ECU is further configured to identify intervening objects along a pathway between the position on the external surface and the surface boundary of the object of interest from one or more images of the pathway. The ECU is further configured to obtain an impedance value for each of the intervening objects and to determine an electric potential at the surface boundary of the object of interest responsive to the signal from the electrode and the impedance values of the intervening objects.

Abstract: Method and systems for ablating nerves including measurement of physiological parameters and/or electrical conduction. The method may include ablating nerves within an artery of a patient such as the renal artery and may include advancing a catheter into the artery, measuring a physiological parameter, emitting an electrical pulse into a wall of the artery, measuring the physiological parameter during or after the step of emitting the electrical pulse, ablating the artery wall, then repeating the steps of measuring the physiological parameter, emitting an electrical pulse, and measuring the physiological parameter during or after the step of emitting the electrical pulse. The change in the physiological parameter caused by the electrical pulse before ablation may be compared to the change in the physiological parameter caused by the electrical pulse after ablation to determine the degree of nerve ablation achieved and whether or not to perform further ablation.

Abstract: Devices and methods for monitoring intracranial physiological parameters, including intracranial pressure, cerebral perfusion pressure, cerebral blood flow, cerebral blood volume, edema status, and brain compliance are disclosed. In one aspect, an apparatus may involve receiving at least one impedance plethysmography signal. Waveforms may be extracted from the impedance plethysmography signals and used for estimating the intracranial physiological parameters. Various characteristics may be determined from the waveforms to aid in the estimation of intracranial physiological parameters.