Abstract:
A method of determining a measure of a tissue state (e.g., glycation end-product or disease state) in an individual. A portion of the tissue of the individual is illuminated with excitation light, then light emitted by the tissue due to fluorescence of a chemical with the tissue responsive to the excitation light is detected. The detected light can be combined with a model relating fluorescence with a measure of tissue state to determine a tissue state. The invention can comprise single wavelength excitation light, scanning of excitation light (illuminating the tissue at a plurality of wavelengths), detection at a single wavelength, scanning of detection wavelengths (detecting emitted light at a plurality of wavelengths), and combinations thereof. The invention also can comprise correction techniques that reduce determination errors due to detection of light other than that from fluorescence of a chemical in the tissue. For example, the reflectance of the tissue can lead to errors if appropriate correction is not employed. The invention can also comprise a variety of models relating fluorescence to a measure of tissue state, including a variety of methods for generating such models. Other biologic information can be used in combination with the fluorescence properties to aid in the determination of a measure of tissue state. The invention also comprises apparatuses suitable for carrying out the method, including appropriate light sources, detectors, and models (for example, implemented on computers) used to relate detected fluorescence and a measure of tissue state.
Abstract:
A method of determining a measure of a tissue state (e.g., glycation end-product or disease state) in an individual. A portion of the tissue of the individual is illuminated with excitation light, then light emitted by the tissue due to fluorescence of a chemical with the tissue responsive to the excitation light is detected. The detected light can be combined with a model relating fluorescence with a measure of tissue state to determine a tissue state. The invention can comprise single wavelength excitation light, scanning of excitation light (illuminating the tissue at a plurality of wavelengths), detection at a single wavelength, scanning of detection wavelengths (detecting emitted light at a plurality of wavelengths), and combinations thereof. The invention also can comprise correction techniques that reduce determination errors due to detection of light other than that from fluorescence of a chemical in the tissue. For example, the reflectance of the tissue can lead to errors if appropriate correction is not employed. The invention can also comprise a variety of models relating fluorescence to a measure of tissue state, including a variety of methods for generating such models. Other biologic information can be used in combination with the fluorescence properties to aid in the determination of a measure of tissue state. The invention also comprises apparatuses suitable for carrying out the method, including appropriate light sources, detectors, and models (for example, implemented on computers) used to relate detected fluorescence and a measure of tissue state.
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.
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.
Abstract:
Embodiments of the present invention provide an apparatus suitable for determining properties of in vivo tissue from spectral information collected from the tissue. An illumination system provides light at a plurality of broadband ranges, which are communicated to an optical probe. The optical probe receives light from the illumination system and transmits it to in vivo tissue, and receives light diffusely reflected in response to the broadband light, emitted from the in vivo tissue by fluorescence thereof in response to the broadband light, or a combination thereof. The optical probe communicates the light to a spectrograph which produces a signal representative of the spectral properties of the light. An analysis system determines a property of the in vivo tissue from the spectral properties. A calibration device mounts such that it is periodically in optical communication with the optical probe.
Abstract:
Methods and apparatuses for the determination of an attribute of the tissue of an individual use non-invasive Raman spectroscopy. For example, the alcohol concentration in the blood or tissue of an individual can be determined. A portion of the tissue is illuminated with light, which propagates into the tissue where it is Raman scattered. The Raman scattered light is detected and can be combined with a model relating Raman spectra to alcohol concentration to determine the alcohol concentration in the blood or tissue. Correction techniques can reduce determination errors due to detection of light other than that from Raman scattering from the alcohol in the tissue. Other biologic information can be used with the Raman spectral properties to aid in the determination of alcohol concentration, for example age, height, weight, medical history and his/her family, ethnicity, skin melanin content, or a combination thereof. The method and apparatus can be optimized to provide reproducible and uniform radiance of the tissue, low tissue sampling error, depth targeting of the tissue layers or sample locations that contain the attribute of interest, efficient collection of Raman spectra, optical throughput, photometric accuracy, large dynamic range, thermal stability, calibration maintenance, calibration transfer, built-in quality control, and ease-of-use.
Abstract:
The present invention provides methods and apparatuses for determining a measure of a tissue state in an individual. Light emitted by tissue of the individual due to fluorescence of a chemical with the tissue detected. The invention can comprise measuring the fluorescence lifetime in either time-domain or frequency domain modes. The invention can also comprise a variety of models relating fluorescence to a measure of tissue state, for example, multivariate models can be developed that relate lifetime trends of one or more constituents to increasing propensity to diabetes and pre-diabetes. Other biologic information can be used in combination with the fluorescence properties to aid in the determination of a measure of tissue state.
Abstract:
Methods and apparatuses for the determination of an attribute of the tissue of an individual use non-invasive Raman spectroscopy. For example, the alcohol concentration in the blood or tissue of an individual can be determined non-invasively. A portion of the tissue is illuminated with light, the light propagates into the tissue where it is Raman scattered within the tissue. The Raman scattered light is then detected and can be combined with a model relating Raman spectra to alcohol concentration in order to determine the alcohol concentration in the blood or tissue of the individual. Correction techniques can be used to reduce determination errors due to detection of light other than that from Raman scattering from the alcohol in the tissue. Other biologic information can be used in combination with the Raman spectral properties to aid in the determination of alcohol concentration, for example age of the individual, height of the individual, weight of the individual, medical history of the individual and his/her family, ethnicity, skin melanin content, or a combination thereof. The method and apparatus can be highly optimized to provide reproducible and, preferably, uniform radiance of the tissue, low tissue sampling error, depth targeting of the tissue layers or sample locations that contain the attribute of interest, efficient collection of Raman spectra from the tissue, high optical throughput, high photometric accuracy, large dynamic range, excellent thermal stability, effective calibration maintenance, effective calibration transfer, built-in quality control, and ease-of-use.
Abstract:
Methods and apparatuses for the determination of an attribute of the tissue of an individual use non-invasive Raman spectroscopy. For example, the alcohol concentration in the blood or tissue of an individual can be determined non-invasively. A portion of the tissue is illuminated with light, the light propagates into the tissue where it is Raman scattered within the tissue. The Raman scattered light is then detected and can be combined with a model relating Raman spectra to alcohol concentration in order to determine the alcohol concentration in the blood or tissue of the individual. Correction techniques can be used to reduce determination errors due to detection of light other than that from Raman scattering from the alcohol in the tissue. Other biologic information can be used in combination with the Raman spectral properties to aid in the determination of alcohol concentration, for example age of the individual, height of the individual, weight of the individual, medical history of the individual and his/her family, ethnicity, skin melanin content, or a combination thereof. The method and apparatus can be highly optimized to provide reproducible and, preferably, uniform radiance of the tissue, low tissue sampling error, depth targeting of the tissue layers or sample locations that contain the attribute of interest, efficient collection of Raman spectra from the tissue, high optical throughput, high photometric accuracy, large dynamic range, excellent thermal stability, effective calibration maintenance, effective calibration transfer, built-in quality control, and ease-of-use.
Abstract:
Methods and apparatuses for the determination of an attribute of the tissue of an individual use non-invasive Raman spectroscopy. For example, the alcohol concentration in the blood or tissue of an individual can be determined non-invasively. A portion of the tissue is illuminated with light, the light propagates into the tissue where it is Raman scattered within the tissue. The Raman scattered light is then detected and can be combined with a model relating Raman spectra to alcohol concentration in order to determine the alcohol concentration in the blood or tissue of the individual. Correction techniques can be used to reduce determination errors due to detection of light other than that from Raman scattering from the alcohol in the tissue. Other biologic information can be used in combination with the Raman spectral properties to aid in the determination of alcohol concentration, for example age of the individual, height of the individual, weight of the individual, medical history of the individual and his/her family, ethnicity, skin melanin content, or a combination thereof. The method and apparatus can be highly optimized to provide reproducible and, preferably, uniform radiance of the tissue, low tissue sampling error, depth targeting of the tissue layers or sample locations that contain the attribute of interest, efficient collection of Raman spectra from the tissue, high optical throughput, high photometric accuracy, large dynamic range, excellent thermal stability, effective calibration maintenance, effective calibration transfer, built-in quality control, and ease-of-use.