Optical system and method for non-invasive imaging of biological tissue

An optical system for in vivo, non-invasive functional neuroimaging of tissue comprising:

• a stimulator constructed to stimulate a selected functional activity of neural tissue of interest;
• an optical module, constructed to be located near said tissue, including an array of input ports and detection ports located in a selected geometrical pattern to provide a multiplicity of photon migration paths in the tissue;
• a spectrophotometer including
• light source means constructed to introduce electromagnetic radiation of visible or infra-red wavelength into the examined neural tissue selectively at the input ports, the wavelength being sensitive to a tissue constituent associated with a physiological response of the imaged functional activity;
• detector means constructed to detect, at said detection ports, radiation of the selected wavelength that has migrated in the stimulated neural tissue from respective input ports;
• and
• a processor receiving signals of said detected radiation from said detector means, and constructed and arranged to create a defined spatial image of the functional activity of neural tissue by effectively producing from the signals from the multiplicity of said photon migration paths, a first data set representing, from a selected view, a spatial image of the neural tissue at rest, a second data set representing, from the same selected view, a spatial image of the neural tissue during stimulation, and a functional image data set that is related to the differences between said first and second data sets.

A system for functional imaging of brain activity of a subject comprising

• a stimulator constructed to stimulate selected brain tissue of interest;
• and
• a brain imager including
• an optical module, adapted to be located near said brain tissue, including an array of light sources constructed to emit optical radiation and an array of light detectors constructed to detect said radiation that has migrated in said brain tissue, said light sources and said light detectors constructed to provide a multiplicity of photon migration paths in said brain tissue, and
• a processor receiving signals of said detected radiation from said detectors, and constructed and arranged to create a defined spatial image of the functional activity of neural tissue by effectively producing a first data set representing, from a selected view, a spatial image of blood in the cortex while the subject is at rest, a second data set representing, from the same selected view, a spatial image of the blood in the cortex during stimulation by said stimulator, and a functional image data set that is related to the differences between said first and second data sets.

A system for functional imaging of brain activity of a subject comprising

• stimulation means for stimulating tissue of interest;
• and
• an imager comprising
• an array of sources of near infrared or visible photons,
• an array of detectors positioned to receive photons from the sources following migration of photons from the sources through the tissue,
• a control system enabling numerous readings of migrated photons to be taken systematically for different source-detector positions relative to the tissue, and
• a processor employing data sets taken during rest and during stimulation, with an imaging algorithm that is based on respectively different probabilities for a given source-detector position, for photons from the source passing through different regions of the volume of the scattering tissue that are located at different positions distributed laterally from a straight reference line between source and detector.

A method of in vivo, non-invasive imaging of tissue change comprising:

• stimulating biological tissue of interest;
• providing an array of input locations and detection locations arranged over a selected geometrical pattern to provide a multiplicity of photon migration paths in the tissue,
• introducing electromagnetic radiation of visible or infra-red wavelength into the tissue selectively at said input locations, said wavelength being sensitive to a constituent of the tissue;
• detecting, at said detection locations, radiation of said selected wavelength that has migrated in the tissue from at least one input location;
• and
• creating a defined spatial image of the tissue based on signals from said multiplicity of said photon migration paths, a succession of data sets representing, from a selected view, a succession of spatial images of the tissue being stimulated and the tissue not being stimulated, and an image data set related to differences between data of said successive data sets of the stimulated and non-stimulated tissue.