Patent ID: 6738653
Filing Date: 2004-05-18
Classification: A61B,G01S

Abstract:
A method for determining a degree of oxygenation of hemoglobin in probed regions of a human body, which comprises the steps of: successively selecting a plurality of probed regions and for each(a) irradiating said probed region with diffuse near-infrared laser light; (b) generating at least one ultrasound wave, chosen from among continuous, pulse or burst waves; (c) focusing said ultrasound wave in at least a focus region of said probed region, to modulate and frequency-shift said light in said probed region; (d) detecting said light, modulated by said ultrasound wave, emerging from said focus region; (e) determining a change in the absorption of said modulated light caused by local changes in said probed region; and (f) calculating from said change in the absorption the change in the degree of hemoglobin oxygenation in the probed region.