Abstract:
An imaging method for spatial distributions of concentrations of absorbers distributed in an object including a radiation step of applying pulsating or continuous light radiated from predetermined incident positions with predetermined wavelengths to the object in the form of a scattering medium containing the absorbers, and a detection step of detecting intensities of light passing through the object at predetermined detection positions. The imaging method also includes a step of finding a plurality photon paths for a plurality of pairs of the incident and detected positions of a model with similar dimensions to the object but without absorbers starting at the incident positions and ending at the detected positions, a step of finding averaged photon-path lengths of the photon paths starting at the incident positions and ending at the detection positions in the model by simulation, a step of finding spatial distributions of absorber concentrations from the averaged photon-path lengths, radiated intensities of the radiated light applied to the object, detected intensities of light detected at the detection positions and optical constants of the absorbers for the radiated light applied to the object, and a step of displaying the spatial distributions of the absorber concentrations.
Abstract:
In an optical measurement system and imaging method adapted to measure in vivo information in a living body without harming the living body, light rays of a plurality of wavelengths which are modulated in intensity with a plurality of different frequencies are irradiated on a plurality of irradiation positions on the surface of a living body, and time-variable changes in living body transmitting light intensity levels corresponding to the respective wavelengths and the respective irradiation positions are measured at different positions on the surface of the living body. Light is utilized to image the results of the measurements, in which the measuring time is shortened by estimating fluctuation attributable to the living body, and the presence or absence of a change in measured signal can be decided easily by displaying an estimation signal and a measured signal at a time.
Abstract:
Light rays of a plurality of wavelengths which are modulated in intensity with a plurality of different frequencies are irradiated on a plurality of irradiation positions on the surface of a living body, and time-variable changes in living body transmitting light intensity levels corresponding to the respective wavelengths and the respective irradiation positions are measured at different positions on the surface of the living body. After completion of the measurement or during the measurement, changes in concentration values of absorbers in the living body are determined from the living body transmitting light intensity levels of the plurality of wavelengths detected at the respective detection points and a measuring point is set on a perpendicular extending through an intermediate point between the incident point and each detection point so as to image a function of the living body. In living body optical measurement system and method, the measuring time is shortened by estimating fluctuation attributable to the living body, the presence or absence of a change in measured signal can be decided easily by displaying an estimation signal and a measured signal at a time, and a local change in. hemodynamic movement can be measured by detecting light rays transmitting through the interior of the living body by the two light detectors disposed at different two sites (equidistant from the light incident point) on a subject and by separating only the local change in hemodynamic movement from an overall change in hemodynamic movement in the living body in accordance with a logarithmic difference between the two detection signals.
Abstract:
In an optical measurement system and imaging method adapted to measure in vivo information in a living body without harming the living body, light rays of a plurality of wavelengths which are modulated in intensity with a plurality of different frequencies are irradiated on a plurality of irradiation positions on the surface of a living body, and time-variable changes in living body transmitting light intensity levels corresponding to the respective wavelengths and the respective irradiation positions are measured at different positions on the surface of the living body. Light is utilized to image the results of the measurements, in which the measuring time is shortened by estimating fluctuation attributable to the living body, and the presence or absence of a change in measured signal can be decided easily by displaying an estimation signal and a measured signal at a time.
Abstract:
In an optical measurement system and imaging method adapted to measure in vivo information in a living body without harming the living body, light rays of a plurality of wavelengths which are modulated in intensity with a plurality of different frequencies are irradiated on a plurality of irradiation positions on the surface of a living body, and time-variable changes in living body transmitting light intensity levels corresponding to the respective wavelengths and the respective irradiation positions are measured at different positions on the surface of the living body. Light is utilized to image the results of the measurements, in which the measuring time is shortened by estimating fluctuation attributable to the living body, and the presence or absence of a change in measured signal can be decided easily by displaying an estimation signal and a measured signal at a time.
Abstract:
In an optical measurement system and imaging method adapted to measure in vivo information in a living body without harming the living body, light rays of a plurality of wavelengths which are modulated in intensity with a plurality of different frequencies are irradiated on a plurality of irradiation positions on the surface of a living body, and time-variable changes in living body transmitting light intensity levels corresponding to the respective wavelengths and the respective irradiation positions are measured at different positions on the surface of the living body. Light is utilized to image the results of the measurements, in which the measuring time is shortened by estimating fluctuation attributable to the living body, and the presence or absence of a change in measured signal can be decided easily by displaying an estimation signal and a measured signal at a time.
Abstract:
Light rays of a plurality of wavelengths which are modulated in intensity with a plurality of different frequencies are irradiated on a plurality of irradiation positions on the surface of a living body, and time-variable changes in living body transmitting light intensity levels corresponding to the respective wavelengths and the respective irradiation positions are measured at different positions on the surface Changes in concentration values of absorbers are determined from the living body transmitting light intensity levels and a measuring point is set on a perpendicular extending through an intermediate point between the incident point and each detection point to image a function of the living body. The measuring time is shortened by estimating fluctuation attributable to the living body, and a local change in hemodynamic movement can be measured by detecting light rays transmitting through the interior of the living body by light detection at two different sites (equidistant from the light incident point) on a subject and by separating only the local change in hemodynamic movement from an overall change in hemodynamic movement in the living body in accordance with a logarithmic difference between the two detection signals.
Abstract:
In an optical measurement system and imaging method adapted to measure in vivo information in a living body without harming the living body, light rays of a plurality of wavelengths which are modulated in intensity with a plurality of different frequencies are irradiated on a plurality of irradiation positions on the surface of a living body, and time-variable changes in living body transmitting light intensity levels corresponding to the respective wavelengths and the respective irradiation positions are measured at different positions on the surface of the living body. Light is utilized to image the results of the measurements, in which the measuring time is shortened by estimating fluctuation attributable to the living body, and the presence or absence of a change in measured signal can be decided easily by displaying an estimation signal and a measured signal at a time.
Abstract:
In an optical measurement system and imaging method adapted to measure in vivo information in a living body without harming the living body, light rays of a plurality of wavelengths which are modulated in intensity with a plurality of different frequencies are irradiated on a plurality of irradiation positions on the surface of a living body, and time-variable changes in living body transmitting light intensity levels corresponding to the respective wavelengths and the respective irradiation positions are measured at different positions on the surface of the living body. Light is utilized to image the results of the measurements, in which the measuring time is shortened by estimating fluctuation attributable to the living body, and the presence or absence of a change in measured signal can be decided easily by displaying an estimation signal and a measured signal at a time.
Abstract:
In an optical measurement system and imaging method adapted to measure in vivo information in a living body without harming the living body, light rays of a plurality of wavelengths which are modulated in intensity with a plurality of different frequencies are irradiated on a plurality of irradiation positions on the surface of a living body, and time-variable changes in living body transmitting light intensity levels corresponding to the respective wavelengths and the respective irradiation positions are measured at different positions on the surface of the living body. Light is utilized to image the results of the measurements, in which the measuring time is shortened by estimating fluctuation attributable to the living body, and the presence or absence of a change in measured signal can be decided easily by displaying an estimation signal and a measured signal at a time.