Patent ID: 6263227
Filing Date: 2001-07-17
Classification: A61B

Abstract:
An apparatus for measuring and imaging blood perfusion in tissue, comprising:a monochromatic laser light source producing a laser light beam;means for shaping the laser light beam;means for directing the laser light beam onto a section of tissue surface in order to illuminate said surface section;means for collecting light scattered from the illuminated section;an image sensor comprising a plurality of photodetectors, each photodetector of the sensor being able to receive collected light from a predetermined sub area of the section of the tissue surface and produce a corresponding electrical output signal linearly related to the detected instantaneous laser light intensity;means for processing the electrical output signals from the plurality of photodetectors to produce processed output signals, said processed output signals comprising:measurements of the power spectrum of the photocurrents generated in the detection of laser light scattered from static tissue and Doppler broadened laser light scattered from moving blood cells;the calculated average Doppler frequency shift for each sub area from which scattered light is detected;the calculated blood volume concentration for each sub area from which scattered light is detected;the calculated blood perfusion for each sub area from which scattered light is detected; andmeasurements of the intensity of the detected scattered light for each predetermined sub area;means for producing an image of the blood perfusion, in the tissue section irradiated, from the processed output signals; andan image display means.