Functional Near Infrared Spectroscopy Imaging System and Method

A functional NIRS imaging system for hemodynamic imaging of subcutaneous tissue, incorporating a computer comprising a first processor, a memory, a persistent storage device and a display, comprising:

• an elastomeric cap;
• an optical fiber bundle, terminating together at a first end plane and terminating dispersively on the inside surface of the elastomeric cap, comprising a set of transmit optical fibers and a set of receive optical fibers;
• a first light source producing a first light beam at a first wavelength and controlled by the computer;
• a second light source producing a second light beam at a second wavelength and controlled by the computer;
• an optical combiner combining the first light beam and the second light beam into a third light beam;
• an optical collimator collimating the third light beam into a fourth light beam;
• a modulation controller including a second processor and a second memory;
• an optical modulation system, controlled by the modulation controller, which accepts the fourth light beam, converts the fourth light beam into a plurality of probe light beams, independently modulates each probe light beam in the plurality of probe light beams, programmatically directs each probe light beam in the plurality of probe light beams into a transmit optical fiber in the set of transmit optical fibers, and programmatically directs a plurality of collected light beams from the set of receive optical fibers into an optical detection system;
• the optical detection system controlled by the first processor and connected to the first memory, which accepts the plurality of collected light beams from the optical modulation system, converts the plurality of collected light beams into a time series of electronic images and stores the time series of electronic images into the memory;
• a computer readable media including a first set of programmed instructions, when executed by the first processor, converts the stored time series of electronic images into a set of hemoglobin oxygen saturation level maps, programmatically displays the set of hemoglobin oxygen saturation level maps on the display and stores the set of hemoglobin oxygen saturation level maps in the persistent storage device.

A method for hemodynamic imaging of subcutaneous tissue utilizing a computer, with a first processor and a first memory, an optical modulator connected to a programmable modulation controller with a second processor and a second memory, and a detector array connected to the computer, the method comprising the steps of:

• providing at least one optical fiber bundle including a set of transmit fibers terminating at the surface of an elastomeric cap and a set of receive fibers terminating at the surface of an elastomeric cap;
• providing a collimated light beam;
• alternating the wavelength of the collimated light beam between wavelengths L1 and L2;
• dividing the collimated light beam into a set of probe beams in the optical modulator;
• modulating the set of probe beams with the optical modulator using a set of modulation codes;
• transmitting the set of probe beams through the set of transmit fibers and through the elastomeric cap wherein each probe beam is transmitted primarily by a single optical fiber;
• collecting photons scattered from the subcutaneous tissue below the elastomeric cap into the set of receive fibers;
• delivering the photons from the set of receive fibers to the detector array wherein each fiber in the at least one optical fiber bundle is imaged onto a subset of detectors in the detector array to form a set of image data;
• processing the set of image data to create two high resolutions images of the subcutaneous tissue wherein the two high resolution images include a first high resolution image corresponding to the concentration of HbO and a second high resolution image corresponding to the concentration of Hb;
• and,
• combining the two high resolution images together to create a hemoglobin oxygen saturation image of the subcutaneous tissue.