Abstract: An optical system for examination of biological tissue includes a light source, a light detector, optics and electronics. The light source generates a light beam to be transmitted to the biological tissue spaced apart from the source. The light detector is located away (i.e., in a non-contact position) from the examined biological tissue and is constructed to detect light that has migrated in the examined biological tissue. The electronics controls the light source and the light detector, and a system separates the reflected photons (e.g., directly reflected or scattered from the surface or superficial photons, i.e., “noise” photons) from the photons that have migrated in the examined biological tissue. This system prevents detection of the “noise” photons by the light detector or, after detection, eliminates the “noise” photons in the detected optical data used for tissue examination.

Abstract: A cognition spectrophotometer system for transcranial brain examination using electromagnetic radiation of a visible or infrared wavelength includes an optical unit, a stimulation module, a remote communication unit, and a processor. The optical unit includes a light source adapted to introduce transcranially from an input port, placed at a input location on the exterior of the head, electromagnetic radiation of the wavelength into the brain, and a light detector adapted to detect, at a detection port placed at a detection location on the exterior of the head, radiation that has migrated in the brain. The stimulation module is constructed and arranged to cause stimulation of a brain activity while introducing the radiation at the input port. The remote communication unit includes a transmitter and a receiver.

Abstract: A system and method for examining or imaging brain functions of a subject includes a light source and a light detector located on the exterior surface of the subject's head. The light source introduces transcranially optical radiation into the brain of a subject, and the light detector detects radiation that has migrated in a brain region from the light source to the detector. The system also provides brain stimulation and evaluates the detected radiation to determine a brain cognitive function of the subject. One embodiment of the system can detect a brain disorder. Another embodiment of the system can detect “deceit.” In addition to the optical module, the system may include other optional modules such as an EEG module, an MEG module, a thermography module, a respiratory module, a skin conductivity module, and a blood pressure module.

Abstract: Methods and systems are described that examine tissue positioned between input ports and a detection port. At lease one source of a visible or infrared wavelength is provided that introduces electromagnetic radiation into the subject. The detection port is optically coupled to a detector that is connected to a detector circuit. Radiation intensities are selected for introduction at the input ports to define a null plane in the tissue. The detection port is positioned relative to the null plane. Radiation is introduced into the subject at the first input port and the radiation that migrates through the tissue is detected. The detector circuit stores a first detector signal corresponding to the first detected radiation. Radiation is introduced at the second input port and is detected. The first detector signal is subtracted from a second detector signal corresponding to the second detected radiation to obtain processed data.

Abstract: An optical method and system for in vivo, non-invasive imaging of biological tissue includes a stimulator and a spectrophotometer. The stimulator is constructed and arranged to stimulate cognition in a subject. The spectrophotometer is co-operatively arranged with the stimulator. The spectrophotometer is coupled to an optical module constructed to provide a multiplicity of arrayed source-detector pairs constructed for direct engagement with the subject. The system includes a light source constructed to introduce electromagnetic radiation of a visible or infra-red wavelength into biological tissue and a light detector constructed to detect optical radiation that has migrated in the tissue.

Abstract: A spectrophotometric system for examination of biological tissue of interest includes a light source, a light coupling system, a light detector, and a processor. The light source is constructed and arranged to emit a light beam of visible or infra-red radiation. The light coupling sytem includes at least one mirror and is constructed and arranged to receive the emitted light beam and scan the light beam for introduction into the biological tissue of interest. The light detector is optically coupled to detect photons of radiation that have migrated over optical paths in the biological tissue of interest. The processor is operatively coupled to the light source and detector and is adapted to determine an optical property of the biological tissue of interest based on the changes between the introduced and detected radiation.

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.

Abstract: As part of an examination device, an input or output optical coupler device for transmitting photons between an optical source or detector and an examined body part includes an array of optical fibers with end portions freely protruding as cantilevers from a support. The optical fibers have the end portions fabricated, sized and distributed to penetrate freely extending hair when the support is placed on the head or other surface of a subject to make optical contact directly over an array of points with the surface of the scalp or skin below the free hair.

Abstract: This invention is a scheme for monitoring a solute in a biological system comprising the steps of delivering light into a biological system (12) containing a solute, the light having a wavelength selected to be in a range wherein the solute is substantially non-absorbing; detecting at least first and second portions of the delivered light, the first portion having traveled through the biological system along one or more paths characterized by a first average path length, and the second portion having traveled through the biological system along one or more paths characterized by a second average path length that is greater than the first average path length; and comparing the first and second portions of the delivered light to monitor concentration of the solute in the biological system.

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.

Abstract: An optical examination technique employs an optical system (15, 45, 100, 150, 200, 260 or 300) for in vivo, non-invasive examination of internal tissue of a subject. The optical system includes an optical module (12 or 14), a controller and a processor. The optical module is arranged for placement on the exterior of the abdomen or chest. The module includes an array of optical input ports and optical detection ports located in a selected geometrical pattern to provide a multiplicity of photon migration paths targeted to examine a selected tissue region, such as an internal organ or an in utero fetus. Each optical input port is constructed to introduce into the examined tissue visible or infrared light emitted from a light source. Each optical detection port is constructed to provide light from the tissue to a light detector.

Abstract: A method and apparatus for transcranial examination of brain activity. Electromagnetic radiation of a selected wavelength is introduced into the brain from an input port located on an exterior of the subject's head. Radiation that has migrated through the subject's head is detected at a detection port to generate detected signals. While introducing and detecting the electromagnetic radiation, stimulation of brain activity is induced. The detected radiation signals are processed, and the processed signals are analyzed to determine a characteristic of the brain activity by correlating the processed signals with the stimulation.

Abstract: Methods and systems are described that examine tissue positioned between input ports and a detection port. At lease one source of a visible or infrared wavelength is provided that introduces electromagnetic radiation into the subject. The detection port is optically coupled to a detector that is connected to a detector circuit. Radiation intensities are selected for introduction at the input ports to define a null plane in the tissue. The detection port is positioned relative to the null plane. Radiation is introduced into the subject at the first input port and the radiation that migrates through the tissue is detected. The detector circuit stores a first detector signal corresponding to the first detected radiation. Radiation is introduced at the second input port and is detected. The first detector signal is subtracted from a second detector signal corresponding to the second detected radiation to obtain processed data.

Abstract: An optical system and method for transcranial in vivo examination of brain tissue includes a spectrophotometer coupled to an array of optical fibers and a processor. The array of optical fibers is constructed to transmit optical radiation of a visible to infra-red wavelength. The optical fibers have distal ends projected through the hair into contact with a surface of the scalp and arranged over a selected geometrical pattern. The spectrophotometer includes at least one light source constructed to emit optical radiation of the visible or infra-red wavelength and at least one light detector constructed to detect radiation that has migrated from a first of said distal ends within the brain tissue to a second of the distal ends. A sequencer is constructed to control introduction of radiation from a first distal end and constructed to control detection of radiation after arriving at a second distal end using a transmission/reception algorithm over the geometrical pattern.

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.

Abstract: This invention is a scheme for monitoring a solute in a biological system comprising the steps of delivering light into a biological system (12) containing a solute, the light having a wavelength selected to be in a range wherein the solute is substantially non-absorbing; detecting at least first and second portions of the delivered light (16, 18, 20), the first portion having traveled through the biological system along one or more paths characterized by a first average path length, and the second portion having traveled through the biological system along one or more as characterized by a second average path length that is greater than the first average path length; and comparing the first and second portions of the delivered light to monitor concentration of the solute in the biological system.

Abstract: One preferred embodiment utilizes differential measurement of radiation that migrated in two migration paths between two source (100) detector (110) pairs placed on the head in a manner that each path is localized in a portion of one hemisphere. The present invention also provides in various embodiments of spectrophotometer systems for in vivo examination of a tissue of a human by measuring changes in electromagnetic radiation scattered and absorbed in a migration path in the tissue.

Abstract: A spectroscopic method and system for examination of biological tissue includes multiple input ports optically connected to at least one light source, multiple detection ports optically connected to at least one detector, a radiation pattern controller coupled to the light source and detector, and a processor. The multiple input ports are arranged to introduce light at input locations into biological tissue and the multiple detection ports are arranged to collect light from detection locations of the biological tissue. The radiation pattern controller is constructed to control patterns of light introduced from the multiple input ports and constructed to control detection of light migrating to the multiple detection ports. The processor is operatively connected to the radiation pattern controller and connected to receive detector signals from the detector, and is constructed to examine a tissue region based on the introduced and detected light patterns.

Abstract: An optical system for in vivo, non-invasive imaging of tissue change includes an optical module with an array of input ports and detection ports located in a selected geometrical pattern to provide a multiplicity of arrayed single source, single detector pairs engaged directly with the subject; a spectrophotometer including a light source constructed to introduce electromagnetic radiation of visible or infra-red wavelength into the examined tissue successively at the input ports, the wavelength being sensitive to a constituent of the imaged tissue; a detector constructed to detect, at the detection ports, radiation of the selected wavelength that has migrated in the tissue from respective input ports; and a processor receiving signals of the detected radiation from the detector, and constructed and arranged to create a defined spatial image of the tissue by effectively producing from signals from the multiplicity of arrayed single source, single detector pairs, a succession of data sets representing, from a s

Abstract: The systems comprise source means for illuminating the fluorophores with diffuse photon density waves of a first specified wavelength, whereby the fluorophores will fluoresce re-radiated diffuse photon density waves of a second wavelength after being illuminated with the diffuse photon density waves of the first specified wavelength; detection means for detecting the re-radiated diffuse photon density waves of the second wavelength, wherein there is a phase shift between the diffuse photon density waves of the first wavelength and the diffuse photon density waves of the second wavelength; and processing means interfaced with the detection means for processing data corresponding to the phase shift and the amplitude of the re-radiated waves to determine concentration and lifetime of the fluorophores as a function of spatial position of the fluorophores in the turbid medium.