And Other Blood Constituents Patents (Class 600/326)
  • Patent number: 8145288
    Abstract: A sensor may be adapted to reduce signal artifacts by deflecting the effects of outside forces and sensor motion. A sensor is provided with a rigid annular structure adapted to reduce the effect of motion of a sensor emitter and/or detector. Further, a method of deflecting or minimizing outside forces and sensor motion is also provided.
    Type: Grant
    Filed: August 22, 2006
    Date of Patent: March 27, 2012
    Assignee: Nellcor Puritan Bennett LLC
    Inventor: Clark R. Baker, Jr.
  • Publication number: 20120059234
    Abstract: An extracorporeal blood chamber for an optical blood monitoring system includes an opaque chamber body in order to prevent inaccuracies when measuring oxygen saturation levels due to light ducting, which can occur at low oxygen saturation levels and low hematocrit levels. In one embodiment, the blood chamber need not include a moat as is present in conventional blood chambers.
    Type: Application
    Filed: September 7, 2010
    Publication date: March 8, 2012
    Applicant: HEMA METRICS, LLC
    Inventors: Louis L. Barrett, Perry N. Law
  • Patent number: 8126527
    Abstract: This document discusses, among other things, quantification of hemoglobin content, and therefore blood volume, of muscle. An analysis of the optical spectra can determine the ratio of hemoglobin (Hb) to myoglobin (Mb) content in intact muscle. The peak position of the in vivo optical spectra from intact tissue is used to determine the ratio of Hb to Mb contributing to the optical signal. The wavelength of the peak is a linear function of the percent contribution of Hb to the optical spectra. Such analysis in combination with known Mb concentrations yields a non-invasive measure of the Hb content for in vivo muscle.
    Type: Grant
    Filed: August 3, 2006
    Date of Patent: February 28, 2012
    Assignee: University of Washington through its Center for Commercialization
    Inventors: David J. Marcinek, Kevin Conley, Kenneth A. Schenkman
  • Publication number: 20120041290
    Abstract: Method and system for early detection of precancerous and other abnormal changes in tissue of various organs. The system comprises a combination of endoscopic scanning with light scattering spectroscopy and improves detection of abnormalities that may otherwise remain undetected. The system may include a probe that collects data of quality that is independent of a distance of the probe from the scanned tissue. During endoscopy, tissue of an organ is imaged using polarized multispectral light scattering scanning and results are presented to a user in a manner that allows detecting abnormal morphological and biochemical changes in the tissue. A determination of whether to perform biopsy may be performed while the endoscopy is being performed, which thus provides guided biopsy. An entire surface of the organ may be rapidly scanned and results of the scanning are analyzed with a reduced time delay.
    Type: Application
    Filed: January 22, 2010
    Publication date: February 16, 2012
    Applicant: BETH ISRAEL DEACONESS MEDICAL CENTER, INC
    Inventor: Lev T. Perelman
  • Patent number: 8078251
    Abstract: A photoplethysmographic sensor designed for use on the presenting portion of a fetus during labor and delivery. The sensor has a non-deployed state in which the sensor presents a smaller footprint, or cross sectional area, for transvaginal insertion. Once the sensor is applied to the fetal tissue it is moved into the deployed state, which has a larger footprint or cross sectional area, than the sensor does in the non-deployed state. The deployed state optimizes the physical distance between the light emitter and the photodetector to maximize the photoplethysmographic measurement accuracy from the fetal tissue.
    Type: Grant
    Filed: June 22, 2006
    Date of Patent: December 13, 2011
    Assignee: Kestrel Labs, Inc.
    Inventors: Jonas Alexander Pologe, Theodore Philip Delianides
  • Publication number: 20110237914
    Abstract: Confidence in a physiological parameter is measured from physiological data responsive to the intensity of multiple wavelengths of optical radiation after tissue attenuation. The physiological parameter is estimated based upon the physiological data. Reference data clusters are stored according to known values of the physiological parameter. At least one of the data clusters is selected according to the estimated physiological parameter. The confidence measure is determined from a comparison of the selected data clusters and the physiological data.
    Type: Application
    Filed: June 3, 2011
    Publication date: September 29, 2011
    Applicant: MASIMO LABORATORIES, INC.
    Inventors: Marcelo Lamego, Mohamed Diab, Ammar Al-Ali
  • Publication number: 20110118574
    Abstract: A physiological signal sensing device for examination of human is provided. The physiological signal sensing device includes a light emitting fiber and a light receiving fiber. The light emitting fiber includes a plurality of light emitting portions, wherein the light emitting fiber provides a plurality of sensing beams, and the sensing beams are respectively emitted through the light emitting portions. The light receiving fiber includes a plurality of light receiving portions. The light receiving fiber corresponds to the light emitting fiber. The sensing beams are emitted through the light emitting portions, reflected or refracted by the human. And then the sensing beams are received by the light receiving portions.
    Type: Application
    Filed: March 10, 2010
    Publication date: May 19, 2011
    Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventors: Wen-Ying Chang, Cheng-Hung Chang
  • Publication number: 20100324390
    Abstract: The invention provides a chest-based oximeter (1) for measuring oxygen saturation of haemoglobin in blood of the chest of a subject, comprising at least one radiation source (5,7) adapted to emit radiation onto the chest, at least one radiation detector (9) adapted to detect radiation reflected from the chest, and a pressure device (11) adapted to apply pressure to the oximeter to connect the oximeter to the chest.
    Type: Application
    Filed: November 3, 2008
    Publication date: December 23, 2010
    Inventors: James Andrew McLaughlin, John McCune Anderson
  • Publication number: 20100168536
    Abstract: A system for monitoring a patient, including: a body-worn monitor having an electrical sensor that measures an electrical waveform from the patient and a wireless transmitter configured to receive the electrical waveform and transmit it over a wireless interface; a computer-based system configured to receive the electrical waveform from the wireless interface and store it in a database; a first algorithm configured to analyze the electrical waveform from the database by comparing it to an secondary electrical waveform previously measured from the patient to determine a property related to the patient's cardiac condition; and a second algorithm configured to analyze the patient's cardiac condition determined by comparing the secondary electrical waveform to the electrical waveform and, in response, transmit a text message.
    Type: Application
    Filed: February 12, 2010
    Publication date: July 1, 2010
    Applicant: TRIAGE WIRELESS, INC.
    Inventors: Matthew BANET, Randon SCHULTZ, Robert MURAD
  • Publication number: 20100130842
    Abstract: The device for the transcutaneous determination of blood gases including a transcutaneous sensor for the measurement of at least one of the parameters of skin carbon dioxide partial pressure (PsCO2) and skin oxygen partial pressure (PsO2) includes at least one sensor for the measurement of the tissue blood flow (F) local with respect to the transcutaneous sensor, and includes a device for the calculation of at least one of the parameters of transcutaneous carbon dioxide partial pressure (tcpCO2) and transcutaneous oxygen partial pressure (tcpO2) from the measured skin carbon dioxide partial pressure (PsCO2) or the measured skin oxygen partial pressure (PsO2), with a factor dependent on the local tissue blood flow (F) being taken into account in the calculation of at least one of the parameters of transcutaneous carbon dioxide partial pressure (tcpCO2) and transcutaneous oxygen partial pressure (tcpO2).
    Type: Application
    Filed: April 28, 2008
    Publication date: May 27, 2010
    Inventors: Josef Hayoz, Rolf Wagner
  • Publication number: 20100081903
    Abstract: Disclosed are methods and devices for measuring a state of anesthesia in a noninvasive manner. Optical techniques may be used to measure changes in a functional near-infrared (fNIR) signal, where the fNIR signal is received in response to directing wavelengths of light in a near-infrared range on a patient. The optical density change may be used to obtain a change in deoxyhemoglobin (deoxy-Hb) concentration and/or a change in an oxyhemoglobin concentration (oxy-Hb). The changes in the deoxy-Hb and/or the oxy-Hb may then be compared to determine a state of anesthesia. The effect of artifacts (e.g., strong surgery room lighting, patient-table tilting, patient intubation/extubation) on the fNIR signal may be removed using a noise removal algorithm. In selecting the noise removal algorithm, a switching technique may be used to select the component analysis algorithm, such as a principal component analysis (PCA), an independent component analysis (ICA), or the like.
    Type: Application
    Filed: September 30, 2009
    Publication date: April 1, 2010
    Applicant: DREXEL UNIVERSITY
    Inventor: Kurtulus Izzetoglu
  • Publication number: 20090156914
    Abstract: A sensor is provided that is appropriate for transcutaneous detection of tissue or blood constituents. A sensor for tissue constituent detection may include a gas collection chamber with a conduit to a sensing component and a conduit from the sensing component to the chamber. A sensor as provided may also include a barrier layer to prevent water from infiltrating the sensor.
    Type: Application
    Filed: February 20, 2009
    Publication date: June 18, 2009
    Applicant: Nellcor Puritan Bennett LLC
    Inventors: Michael P. O'Neil, David B. Swedlow
  • Patent number: 7473227
    Abstract: The invention concerns a medical device for implantation in a body, comprising a stimulation unit, a sleep detector unit having at least one signal input which is adapted to detect a sleep condition of the body and to produce a sleep signal, an apnea detector unit which is adapted to detect sleep apnea in dependence on at least one body signal caused by the body and to produce an apnea signal, a therapy unit which is at least indirectly connected to the stimulation unit! the sleep detector unit and to the apnea detector unit and which is adapted to produce, in dependence on the apnea signal and the sleep signal, at least one apnea therapy signal which represents therapy information for preventing and/or for the treatment of sleep apnea, and to send same to the stimulation unit.
    Type: Grant
    Filed: September 2, 2004
    Date of Patent: January 6, 2009
    Assignee: Biotronik GmbH & Co.KG
    Inventors: William Hsu, Mark Johnson, Gerlad Czygan
  • Publication number: 20090005663
    Abstract: An apparatus for the measurement of at least one analyte in the blood of a patient, which includes a light source generating broadband light and a light-transmission arrangement having a plurality of transmitting fibers is positioned for simultaneously transmitting multiple wavelengths of the broadband light from the light source to the blood of the patient. The measurement apparatus further includes an optical fiber arrangement having a plurality of light detector fibers for leading multi-wavelength light, in spectrally unseparated form, transmitted through, or reflected from, the blood and a light detection arrangement for receiving the multi-wavelength light in its spectrally unseparated form from the optical fiber arrangement, for spectrally decomposing the received light, and for determining amplitudes of selected wavelengths of the decomposed light.
    Type: Application
    Filed: September 8, 2008
    Publication date: January 1, 2009
    Applicant: Edwards Lifesciences Corporation
    Inventors: Dawood Parker, David Keith Harrison
  • Patent number: 7384794
    Abstract: Fibres with an extraction phase coated thereon in combination with a positioning device are described to perform adsorption of components of interest from an animal or animal tissue for the investigation of living systems. A number of interfaces to analytical instrumentation are disclosed including mass spectrometry, LC/MS, MALDI and CE as well as direct spectroscopic on-fibre measurement.
    Type: Grant
    Filed: March 6, 2003
    Date of Patent: June 10, 2008
    Inventor: Janusz B. Pawliszyn
  • Patent number: 7254430
    Abstract: Blood sugar levels are non-invasively measured based on temperature measurements. Blood sugar levels obtained by non-invasive measurements of temperatures are corrected by blood oxygen saturation and the volume of blood flow so that the measurement data can be stabilized.
    Type: Grant
    Filed: June 30, 2005
    Date of Patent: August 7, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Ok-Kyung Cho, Yoon-Ok Kim
  • Patent number: 7254426
    Abstract: Blood sugar levels are non-invasively measured based on temperature measurements. Blood sugar levels obtained by non-invasive measurements of temperatures are corrected by blood oxygen saturation and the volume of blood flow so that the measurement data can be stabilized.
    Type: Grant
    Filed: July 17, 2003
    Date of Patent: August 7, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Ok-Kyung Cho, Yoon-Ok Kim
  • Patent number: 7254428
    Abstract: Blood sugar levels are measured non-invasively based on temperature measurement. Non-invasively measured blood sugar level values obtained by a temperature measurement scheme are corrected by blood oxygen saturation and blood flow volume, thereby stabilizing the measurement data. A guide is provided for guiding an analyte to a measurement portion.
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: August 7, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Ok-Kyung Cho, Yoon-Ok Kim, Nobuhiko Sato, Hiroshi Mitsumaki
  • Patent number: 7251515
    Abstract: Blood sugar levels are measured non-invasively based on temperature measurement. Non-invasively measured blood sugar level values obtained by a temperature measurement scheme are corrected by blood oxygen saturation and blood flow volume, thereby stabilizing the measurement data. The shape or color of control buttons for controlling measurement are associated with the function of each button such that the buttons can be identified either visually or by touch.
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: July 31, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Ok-Kyung Cho, Yoon-Ok Kim, Koji Nagata, Hiroshi Mitsumaki
  • Patent number: 7251517
    Abstract: Blood sugar levels are measured non-invasively based on temperature measurement. Non-invasively measured blood sugar level values obtained by a temperature measurement scheme are corrected by blood oxygen saturation and blood flow volume, thereby stabilizing the measurement data.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: July 31, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Ok-Kyung Cho, Yoon-Ok Kim, Kurazo Maruoka, Hiroshi Mitsumaki
  • Patent number: 7251514
    Abstract: Blood sugar levels are measured non-invasively based on temperature measurement. Non-invasively measured blood sugar level values obtained by a temperature measurement scheme are corrected by blood oxygen saturation and blood flow volume, thereby stabilizing the measurement data. If the measured blood sugar level is larger than a warning value, a warning is issued.
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: July 31, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Ok-Kyung Cho, Yoon-Ok Kim, Katsumi Ouchi, Hiroshi Mitsumaki
  • Patent number: 7248909
    Abstract: A device and method utilizes a broadband diffuse optical spectroscopy (DOS) system to dynamically calculate the concentrations of multiple chromophores in vivo using a non-invasive probe. The device and method permit dynamic monitoring of multiple in vivo tissue chromophores non-invasively with sensitivities necessary for effective therapeutic monitoring. The device includes a probe containing first and second source optical fibers as well as first and second detector optical fibers. The probe is placed adjacent to a sample of interest and detects reflected light which is passed to a proximally located detector and spectrometer. The concentrations of multiple chromophores are determined in real time. In a preferred embodiment, the multiple tissue chromophores include at least two of methemoglobin (MetHb), deoxyhemoglobin (Hb-R), oxyhemoglobin (Hb-O2), water (H2O), and methylene blue (MB).
    Type: Grant
    Filed: April 12, 2005
    Date of Patent: July 24, 2007
    Assignee: The Regents of the University of California
    Inventors: Jangwoen Lee, Bruce J. Tromberg, Albert E. Cerussi, Matthew Brenner
  • Patent number: 7215983
    Abstract: Blood sugar levels are measured non-invasively based on temperature measurement. Non-invasively measured blood sugar level values obtained by a temperature measurement scheme are corrected by blood oxygen saturation and blood flow volume, thereby stabilizing the measurement data.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: May 8, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Ok-Kyung Cho, Yoon-Ok Kim, Hideharu Hattori, Hiroshi Mitsumaki
  • Patent number: 7130672
    Abstract: Apparatus for monitoring a plurality of tissue viability parameters of a tissue layer element, in which two different illumination sources are used via a common illumination element in contact with the tissue. One illumination source is used for monitoring blood flow rate and optionally flavoprotein concentration, and collection fibers are provided to receive the appropriate radiation from the tissue. The other illuminating radiation is used for monitoring any one of and preferably all of NADH, blood volume and blood oxygenation state of the tissue element, and collection fibers are provided to receive the appropriate radiation from the tissue. In one embodiment, the wavelengths of the two illumination sources are similar, and common collection fibers for the two illuminating radiations are used. In another embodiment, the respective collection fibers are distanced from the illumination point at different distances correlated to the ratio of the first and second illuminating wavelengths.
    Type: Grant
    Filed: September 25, 2001
    Date of Patent: October 31, 2006
    Assignee: Critisense Ltd.
    Inventors: Eliahu Pewzner, Avraham Mayevsky
  • Patent number: 6954661
    Abstract: Blood sugar levels are measured non-invasively based on temperature measurement. Measured blood sugar levels are corrected using blood oxygen saturation and blood flow volume. The measurement data is further stabilized by taking into consideration the influences of interfering substances on blood oxygen saturation.
    Type: Grant
    Filed: August 15, 2003
    Date of Patent: October 11, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Ok-Kyung Cho, Yoon-Ok Kim
  • Patent number: 6944485
    Abstract: A hyperbaric resuscitation system (10) includes a hyperbaric chamber (20) having a volume sufficient to enclose a human patient (1) and at least two operating personnel (60). The system (10) also includes a device for pressurizing the hyperbaric chamber (20) to at least 1.5 atmospheres with air. The concentration of oxygen in high pressure, oxygen-rich gas to be breathed by the patient (1) provided by an independent system (41) at chamber pressure is automatically regulated by a regulating system (33) which receives information about the amount of oxygen in cerebral tissue of the patient (1) from a spectrophotometer (51, 52). Although devices for measuring the exact amount of oxygen in cerebral tissue do not yet exist, the presently available devices can show trends in the amount of oxygen in the tissue. Since the physician working on a patient in a hyperbaric resuscitation system is more concerned about trending than exact values, the present system can still be of great benefit in resuscitating patients.
    Type: Grant
    Filed: April 20, 2000
    Date of Patent: September 13, 2005
    Inventors: Keith W. Van Meter, Frederick A. Kriedt
  • Patent number: 6934571
    Abstract: An embodiment of the present invention comprises a self-contained breathing apparatus (SCBA) mask that incorporates a series of physiologic sensors. These physiologic sensors are mounted on the interior of the SCBA mask in such a way as to contact the facial skin of an individual wearing the mask. The physiologic sensors monitor, among other things, heart rate and carbon monoxide and oxygen saturation levels. The physiologic sensors are connected to a transmitting apparatus attached to the SCBA. The SCBA transmitter sends output data from the physiologic sensors to a remote processor. The SCBA transmitter also sends location information of the individual wearing the SCBA mask to the remote processor. The remote processor compiles the physiologic and location data for the wearer of the SCBA and transmits a signal back to the SCBA receiver which, in turn, sends a signal to a display integrated into a SCBA mask. The display indicates to the individual his physiologic status.
    Type: Grant
    Filed: August 16, 2002
    Date of Patent: August 23, 2005
    Assignee: BioAsyst, L.L.C.
    Inventors: William Paul Wiesmann, Loland Alexander Pranger, Mary Sandra Bogucki
  • Publication number: 20040260165
    Abstract: Blood sugar levels are measured non-invasively based on temperature measurement. Measured blood sugar levels are corrected using blood oxygen saturation and blood flow volume. The measurement data is further stabilized by taking into consideration the influences of interfering substances on blood oxygen saturation.
    Type: Application
    Filed: August 15, 2003
    Publication date: December 23, 2004
    Inventors: Ok-Kyung Cho, Yoon-Ok Kim
  • Publication number: 20040242980
    Abstract: A monitor has a primary input from which a spectral characteristic of a tissue site can be derived. The monitor also has a secondary input from which at least one parameter can be determined. A compensation relationship of the spectral characteristic, the parameter and a compensated physiological measurement is determined. A processor is configured to output the compensated physiological measurement in response to the primary input and the secondary input utilizing the compensation relationship.
    Type: Application
    Filed: November 14, 2003
    Publication date: December 2, 2004
    Inventors: Massi E. Kiani, Mohamed Diab, Ammar Al-Ali, Walter M. Weber
  • Publication number: 20040225209
    Abstract: Blood sugar levels are non-invasively measured based on temperature measurements. Blood sugar levels obtained by non-invasive measurements of temperatures are corrected by blood oxygen saturation and the volume of blood flow so that the measurement data can be stabilized.
    Type: Application
    Filed: July 17, 2003
    Publication date: November 11, 2004
    Inventors: Ok-Kyung Cho, Yoon-Ok Kim
  • Patent number: 6766188
    Abstract: A device and method in accordance with the invention for determining the oxygen partial pressure (PO2) of a tissue by irradiating the tissue with optical radiation such that the light is emitted from the tissue, and by collecting the reflected or transmitted light from the tissue to form an optical spectrum. A spectral processor determines the PO2 level in tissue by processing this spectrum with a previously-constructed spectral calibration model. The tissue may, for example, be disposed underneath a covering tissue, such as skin, of a patient, and the tissue illuminated and light collected through the skin. Alternatively, direct tissue illumination and collection may be effected with a hand-held or endoscopic probe. A preferred system also determines pH from the same spectrum, and the processor may determine critical conditions and issue warnings based on parameter values.
    Type: Grant
    Filed: October 11, 2002
    Date of Patent: July 20, 2004
    Assignee: University of Massachusetts
    Inventor: Babs R. Soller
  • Patent number: 6749565
    Abstract: A rapid diagnosis method for organ specific disease state is based on obtaining an infrared absorbance spectra of a patient's blood at a frequency range from about 400 cm−1 to about 2000 cm−1 and further from about 3000 cm−1 to about 3100 cm−1. Comparing it with the predetermined normal infrared absorbance spectra of known healthy subjects for the presence or absence of predetermined features such as increase or decrease of infrared absorbance, peaks at particular frequencies allows for accurate diagnosis of a disease of an organ, including most major organs such as a heart, lungs, stomach, liver, kidneys, brain, etc.
    Type: Grant
    Filed: May 25, 2001
    Date of Patent: June 15, 2004
    Inventor: Victor Chudner
  • Patent number: 6708048
    Abstract: A pathlength corrected spectrophotometer for tissue examination includes an oscillator for generating a carrier waveform of a selected frequency, an LED light source for generating light of a selected wavelength that is intensity modulated at the selected frequency introduced to a subject, and a photodiode detector for detecting light that has migrated in the tissue of the subject. The spectrophotometer also includes a phase detector for measuring a phase shift between the introduced and detected light, a magnitude detector for determination of light attenuation in the examined tissue, and a processor adapted to calculate the photon migration pathlength and determine a physiological property of the examined tissue based on the pathlength and on the attenuation data.
    Type: Grant
    Filed: January 13, 1999
    Date of Patent: March 16, 2004
    Assignee: Non-Invasive Technology, Inc.
    Inventor: Britton Chance
  • Publication number: 20040024298
    Abstract: Spectral variation contributed from the absorbance of unwanted correlated signals, such as blood at variable pathlengths between an in vivo catheter optic probe and a coronary vessel wall is an obstacle in the detection of vulnerable plaque. Preprocessing methods are described to reduce the impact of blood upon the spectral signal, based on the principles of Orthogonal Subspace Projection (OSP) and Generalized Least Square (GLS). The multivariate discrimination models used on the processed spectral information reduce the number of independent factors that include contributions from blood. The disclosed chemometric processing including preprocessing methods provide for in vivo spectral detection of medical analytes within the human body and in particular within the coronary vessel wall.
    Type: Application
    Filed: April 30, 2003
    Publication date: February 5, 2004
    Applicant: InfraReDx, Inc.
    Inventors: Barbara J. Marshik-Geurts, Huwei Tan
  • Patent number: 6654622
    Abstract: A device for the combined measurement of the arterial oxygen saturation and the transcutaneous CO2 partial pressure on an ear lobe comprises a sensor. The sensor has means for pulse oximetric measurement of the arterial oxygen saturation, means for measurement of the transcutaneous CO2 partial pressure and means for warming a sensor contact surface intended for contact with the ear lobe. The device makes simple and reliable measurement of the arterial oxygen saturation and the transcutaneous CO2 partial pressure possible on an ear lobe.
    Type: Grant
    Filed: December 1, 1999
    Date of Patent: November 25, 2003
    Assignee: Linde Medical Sensors AG
    Inventors: Patrick Eberhard, Jean-Pierre Palma
  • Patent number: 6594513
    Abstract: A spectrophotometric method and apparatus for determining the degree of oxygen saturation of the hemoglobin in the blood within a body part utilizes differences in light absorption based on differences in extinction coefficients at different wavelengths. Oxygen saturation is determined by utilizing absorption at three or more wavelengths of radiation preferably in the near red and infrared region (NIR) of the spectrum, specifically tailored to two or more components to be detected by the radiation. The first (reference) wavelength is preferably chosen to be at an isosbestic point for the two components, commonly the oxygenated and deoxygenated forms of hemoglobin. The absorption at the isosbestic point is subtracted from the absorption at the other wavelengths. Using these differences in absorption, the amount of each of the components encountered by the light may be determined without determination of pathlength, which would be required to determine the concentration.
    Type: Grant
    Filed: January 12, 2000
    Date of Patent: July 15, 2003
    Inventors: Paul D. Jobsis, Frans F. Jobsis
  • Patent number: 6574490
    Abstract: An apparatus and method for non-invasive measurement of glucose in human tissue by quantitative infrared spectroscopy to clinically relevant levels of precision and accuracy. The system includes six subsystems optimized to contend with the complexities of the tissue spectrum, high signal-to-noise ratio and photometric accuracy requirements, tissue sampling errors, calibration maintenance problems, and calibration transfer problems. The six subsystems include an illumination subsystem, a tissue sampling subsystem, a calibration maintenance subsystem, an FTIR spectrometer subsystem, a data acquisition subsystem, and a computing subsystem.
    Type: Grant
    Filed: April 11, 2001
    Date of Patent: June 3, 2003
    Assignee: Rio Grande Medical Technologies, Inc.
    Inventors: Russell E. Abbink, Robert D. Johnson, John D. Maynard
  • Patent number: 6564076
    Abstract: Methods and apparatus using the principles of time-resolved spectroscopy are disclosed. The present invention employs incident light pulses of sufficiently short duration to permit the rate of the rise and decay of such pulses to be measured. Consequently, the rate of decay, u, permits a determination of the concentration of an absorptive pigment, such as hemoglobin. The present invention also allows the precise path length the photons travel to be determined. Using this path length information and by measuring changes in optical density using known continuous light (CW) spectrophotometry systems, the methods and apparatus disclosed allow changes in the concentration of an absorptive pigment to be correctly be measured. From these data, the oxygenation state of a tissue region, such as the brain, can be accurately determined in real time.
    Type: Grant
    Filed: November 21, 2000
    Date of Patent: May 13, 2003
    Assignee: Non-Invasive Technology, Inc.
    Inventor: Britton Chance
  • Patent number: 6421548
    Abstract: This involves a non-invasive glucose measurement device and a process for determining blood glucose level in the human body using the device. In typical operation, the glucose measurement device is self-normalizing in that it does not employ an independent reference sample in its operation. The device uses attenuated total reflection (ATR) infrared spectroscopy. Preferably, the device is used on a fingertip and compares two specific regions of a measured infrared spectrum to determine the blood glucose level of the user. Clearly, this device is especially suitable for monitoring glucose levels in the human body, and is especially beneficial to users having diabetes mellitus. The device and procedure may be used for other analyte materials which exhibit unique mid-IR signatures of the type described herein and that are found in appropriate regions of the outer skin.
    Type: Grant
    Filed: September 22, 2000
    Date of Patent: July 16, 2002
    Assignee: MedOptix, Inc.
    Inventors: Herbert L. Berman, Jeffrey N. Roe
  • Patent number: 6402689
    Abstract: Methods of monitoring and evaluating the status of a tumor undergoing treatment includes monitoring in vivo at least one physiological parameter associated with a tumor in a subject undergoing treatment, transmitting data from an in situ located sensor to a receiver external of the subject, analyzing the transmitted data, repeating the monitoring and transmitting steps at sequential points in time and evaluating a treatment strategy. The method provides dynamic tracking of the monitored parameters over time. The method can also include identifying in a substantially real time manner when conditions are favorable for treatment and when conditions are unfavorable for treatment and can verify or quantify how much of a known drug dose or radiation dose was actually received at the tumor. The method can include remote transmission from a non-clinical site to allow oversight of the tumor's condition even during non-active treatment periods (in between active treatments).
    Type: Grant
    Filed: September 29, 1999
    Date of Patent: June 11, 2002
    Assignees: Sicel Technologies, Inc., North Carolina State University
    Inventors: Charles W. Scarantino, H. Troy Nagle, Leslie C. Hall, Jeffrey Mueller, Chang-Soo Kim
  • Patent number: 5978691
    Abstract: A device and method for noninvasively quantifying important physiological parameters in blood. The device and method utilizes changes in molecular behavior induced by thermal energy of change to facilitate the measurement of the physiological parameters in blood. Oxygen saturation, partial pressure of oxygen, partial pressure of carbon dioxide, concentration of bicarbonate ion and total carbon dioxide, acid-base balance, base excess, hemoglobin level, hematocrit, oxyhemoglobin level, deoxyhemoglobin level, and oxygen content can all be determined quickly, easily, and continuously. There is no need for skin puncture or laboratory analysis.
    Type: Grant
    Filed: July 10, 1997
    Date of Patent: November 2, 1999
    Inventor: Alexander Knight Mills
  • Patent number: 5891022
    Abstract: A photoplethysmographic measurement device that utilizes wavelength division multiplexing is provided. Signals from multiple light emitters are combined into a single multiplexed light signal in a test unit before being delivered to a physically separated probe head attached to a test subject. The probe then causes the single multiplexed signal to be transmitted through a tissue under test on the test subject, after which it is processed to determine a blood analyte level of the test subject. By combining the light signals into a single multiplexed signal before delivering the signals to the probe, a single light guide, such as a single optical fiber, can be used to deliver the signals to the probe, thereby reducing system implementation cost and increasing the flexibility of the probe cable. In addition, the invention allows the signals from the light emitters to be directed into the test subject from a single point source, which can significantly increase measurement accuracy.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: April 6, 1999
    Assignee: Ohmeda Inc.
    Inventor: Jonas A. Pologe
  • Patent number: 5838429
    Abstract: The invention relates to an apparatus for measuring physiological parameters of blood conveyed within an extracorporeal circulatory system. Two light sources (1a, 1b) emit light of varying wavelength into a spherical cavity (3) that comprises a reflective inner surface (3a). Light sensor means (2) receives part of the light propagating within the cavity (3). A tube portion of the extracorporeal circulation can be inserted into a second cavity (4) such that the light (La, Lb) emitted by the light sources encounters the boundary surface between the blood and an inner wall of the tube. The light returns to the cavity (3) at least to an extent by means of reflection and/or transmission.
    Type: Grant
    Filed: May 14, 1997
    Date of Patent: November 17, 1998
    Assignee: Stockert Instrumente GmbH
    Inventor: Andreas Hahn