Abstract: A solution for reducing interference in noninvasive spectroscopic measurements of tissue and blood analytes is provided. By applying a basis set representing various tissue components to a collected sample measurement, measurement interferences resulting from the heterogeneity of tissue, sampling site differences, patient-to-patient variation, physiological variation, and instrumental differences are reduced. Consequently, the transformed sample measurements are more suitable for developing calibrations that are robust with respect to sample-to-sample variation, variation through time, and instrument related differences. In the calibration phase, data associated with a particular tissue sample site is corrected using a selected subset of data within the same data set. This method reduces the complexity of the data and reduces the intra-subject, inter-subject, and inter-instrument variations by removing interference specific to the respective data subset.

Abstract: A flex circuit optical sensor has an integrated Faraday shield. A conductive trace layer disposed on a substrate is used to form a conductive grid which shields the face of a photodetector. A conductive ink layer is formed on a substrate side opposite the trace layer. The back and sides of the detector are shielded by flex circuit flaps that have the conductive ink layer but substantially exclude the trace layer so as to fold over and closely adhere to the detector body. The shielded substrate flaps advantageously eliminate a separate detector shield, which is typically fabricated with an etched copper part that must be attached to a flex circuit before mounting the detector.

Abstract: A probe device for use in non-invasive optical measurements of at least one parameter of the patient's blood. The probe device comprises a finger holder in the form of a clip member that secures a fingertip between its clamping legs. The probe device supports a measuring unit for applying optical measurements to a measurement location on the finger and carries a pressurizing assembly operable for applying controllably variable, substantially under-systolic pressure to the finger in the vicinity of the measurement location. Several measurement sessions are performed at the measurement location with at least two different 3 wavelength of incident light to detect light response of the medium and generate measured data indicative thereof, and the pressure applied to the vicinity of the measurement location is simultaneously varied during measurements. The light response of the medium corresponding to different wavelength of the incident light and different pressure values during measurements.

Abstract: An ophthalmic lens comprising a receptor moiety can be used to determine the amount of an analyte in an ocular fluid. The receptor moiety can bind either a specific analyte or a detectably labeled competitor moiety. The amount of detectably labeled competitor moiety which is displaced from the receptor moiety by the analyte is measured and provides a means of determining analyte concentration in an ocular fluid, such as tears, aqueous humor, or interstitial fluid. The concentration of the analyte in the ocular fluid, in turn, indicates the concentration of the analyte in a fluid or tissue sample of the body, such as blood or intracellular fluid.

Abstract: The present invention relates to a device for removing liquid from endogenic tissue and determining concentrations of substances in this liquid, in which a hollow chamber (3), which is placeable in direct contact on the skin (1) covering the tissue with at least one contact opening (3.1) disposed on a contact surface (3.2) and the hollow chamber (3) is connected to a low pressure-producing element (P) via a channel (4.1).

Abstract: An EMG monitoring system includes a matrix of detection electrode arrays that is positioned on the patient along his or her spine. The arrays are electrically connected through a switching mechanism to EMG amplifiers that are included in conventional monitoring instrumentation. A switch controller operates the switches to provide signals to the EMG amplifiers from selected sets of detection electrode arrays. The controller controls the switches to provide signals simultaneously to each EMG amplifier. If the monitoring instrumentation includes four EMG amplifiers, the matrix of electrode arrays and the switching mechanism may be used to take simultaneous measurements at two different spinal levels. If additional EMG amplifiers are included, simultaneous measurements at additional spinal levels may also be made. The matrix may also include redundant arrays and/or electrodes, such that the clinician can select the sets of electrodes that conform to the size of the patient.

Abstract: There is provided a method and a system for determining the concentration of chromophores and reconstructing images in turbid media, such as animal tissues, using a continuous wave optical approach. In particular the approach is based on measurements of attenuation signals and the calculation of concentrations of chromophores using a predetermined scatter law. The system comprises a continuous wave photon migration model calculator coupled to an optical source and detector for estimating concentrations of chromophores and scatter parameters used in image reconstruction.

Abstract: A method and an apparatus for distinguishing concentrations of blood constituents among distinct vascular components in situ. The method has steps of inducing periodic vibration, characterized by a frequency, in a limb of a person in such as manner as to selectively excite a resonant response in a specified blood vessel of the person, an artery or a vein, illuminating the limb of the person with a light source, and synchronously detecting a plethysmographic signal for discriminating response attributable to the specified blood vessel.

Abstract: An optical sensor includes photoemitter and photodetector elements at multiple spacings (d1, d2) for the purpose of measuring the bulk absorptivity (?) of an area immediately surrounding and including a hemodialysis access site, and the absorptivity (?o) of the tissue itself. At least one photoemitter element and at least one photodetector element are provided, the total number of photoemitter and photodetector elements being at least three. The photoemitter and photodetector elements are collinear and alternatingly arranged, thereby allowing the direct transcutaneous determination of vascular access blood flow.

Abstract: Method and device for the sensing of the electromyographic activity of an individual's bladder detrusor muscle, where an elongated electrode is inserted through the individual's urethra, so that the proximal end of the electrode becomes positioned in the bladder, and the bladder is charged with a fluid having electrical conductivity, and the electrical potential of the detrusor muscle, mediated by the fluid, is sensed by the electrode.

Abstract: An alignment device and related systems and methods for aligning at least one apparatus with respect to a surface of a tissue. The alignment device comprises a tissue interface member suitable for positioning on the surface of the tissue and mating with the apparatus to maintain alignment of the apparatus during an operation of the apparatus. The alignment device is useful to align various apparatus that are part of a continuous analyte monitoring system.

Abstract: Blood glucose concentrations are measured by non-invasive methods and apparatus using visual pigment bleaching in conjunction with psychophysical methodologies. Bleaching light of selected wavelengths is projected through the pupil of the eye of an observer onto the fundus to bleach visual pigments in the eye. The observer's psychophysical response to a visual stimulus is then measured to obtain information regarding the rate of regeneration of the visual pigments. From the rate of pigment regeneration, blood glucose concentrations are measured accurately. The psychophysical methodologies that may be used with the invention include visual acuity tests and color-matching tests.

Abstract: The present invention pertains to a system and method for transdermal sampling, comprising: at least one sampler for retrieving and transferring at least one analyte obtained transdermally from the skin of a subject; at least one detector system for identifying and quantifying said at least one analyte; and at least one logic module for (i) receiving and storing input data from said at least one detector, (ii) relating the input data to other data obtained from the subject, (iii) displaying output information, (iv) transmitting the output information to another system, and (v) controlling the operation of said at least one sampler and at least one detector.

Abstract: The invention relates to the calibration of a pulse oximeter intended for non-invasively determining the amount of at least two light-absorbing substances in the blood of a subject. In order to bring about a solution by means of which the effects caused by the tissue of the subject can be taken into account in connection with the calibration of a pulse oximeter, initial characterization measurements are carried out for a pulse oximeter calibrated under nominal conditions. Based on the characterization measurements, nominal characteristics are established describing the conditions under which nominal calibration has been defined, and reference data indicating the nominal characteristics are stored. In-vivo measurements are then performed on living tissue and based on the in-vivo measurements and the reference data stored, tissue-induced changes in the nominal characteristics are determined.

Abstract: A system and method embodying the invention can be used to detect a characteristic or condition of a patient. A method embodying the invention may include the steps of illuminating a portion of a skin of the patient with light, detecting a frequency spectrum of light scattered from the skin, determining, from first and second portions of the spectrum, a first parameter indicative of a blood content of the skin and a second parameter indicative of a melanin content of the skin, determining, from a third portion of the spectrum, a third parameter indicative of an uncorrected bilirubin concentration, and calculating a corrected bilirubin concentration based on the first, second and third parameters.

Abstract: A method and devices for differentiating in a given area of tissue a tumorous tissue from a normal tissue, the method comprising measuring a plurality of tissue impedance over a range of tissue temperatures and comparing the measured tissue impedance with reference tissue impedance of the normal tissue adapted for tissue differentiation. The management of tissue temperatures may be accomplished with a probe arrangement comprising two elements of different electromotive potential conductively connected at a probe junction, and passing an electrical current through the elements to reduce or raise a temperature of the probe junction in accordance with the Peltier effect.

Abstract: An intelligent, rule-based processor provides recognition of individual pulses in a pulse oximeter-derived photo-plethysmograph waveform. Pulse recognition occurs in two stages. The first stage identifies candidate pulses in the plethysmograph waveform. The candidate pulse stage identifies points in the waveform representing peaks and valleys corresponding to an idealized triangular wave model of the waveform pulses. At this stage, waveform features that do not correspond to this model are removed, including the characteristic dicrotic notch. The second stage applies a plethysmograph model to the candidate pulses and decides which pulses satisfies this model. This is done by first calculating certain pulse features and then applying different checks to identify physiologically acceptable features.

Abstract: A method for removing motion artifacts from devices for sensing bodily parameters and apparatus and system for effecting same. The method includes analyzing segments of measured data representing bodily parameters and possibly noise from motion artifacts. Each segment of measured data may correspond to a single light signal transmitted and detected after transmission or reflection through bodily tissue. Each data segment is frequency analyzed to determine up to three candidate peaks for further analysis. Each of the up to three candidate frequencies may be filtered and various parameters associated with each of the up to three candidate frequencies are calculated. The best frequency, if one exists, is determined by arbitrating the candidate frequencies using the calculated parameters according to predefined criteria. If a best frequency is found, a pulse rate and SpO2 may be output. If a best frequency is not found, other, conventional techniques for calculating pulse rate and SpO2 may be used.

Abstract: A method and apparatus for differentiating in a given area of tissue a tumorous tissue from a normal tissue, the method comprising measuring a plurality of tissue impedance over a range of tissue temperatures and comparing the measured tissue impedance with reference tissue impedance of the normal tissue adapted for tissue differentiation. The management of tissue temperatures may be accomplished with a probe arrangement comprising two elements of different electromotive potential conductively connected at a probe junction, and passing an electrical current through the elements to reduce or raise a temperature of the probe junction in accordance with the Peltier effect.

Abstract: A method for diagnosing mastitis of cows, includes the steps of (1) irradiating visual light rays and/or near infrared rays in a wavelength range of 400 to 2500 nm into urine, raw milk or a mammary gland of a cow, (2) detecting an intensity of transmitted light rays, reflected light rays or transmitted and reflected light rays from said urine, raw milk or mammary gland, and (3) effecting multivariate regression analysis, and (4) diagnosing the presence of the mastitis of the cow.