Patent ID: 6751490
Filing Date: 2004-06-15
Classification: A61B

Abstract:
A system for measuring hemoglobin concentrations and hematocrit comprising:a pulsed optical source adapted to generate short optical pulses to provide irradiation of a blood vessel or tissue site; an optical delivery system adapted to deliver the optical pulses to the blood vessel or tissue site, where the optical deliver system includes a proximal end in light communication with the source and a distal end out of which the optical pulses exit; an adjustable probe including a housing, an acoustic transducer adapted to detect pressure waves resulting from the optical pulses impinging on the blood vessel or tissue site and mounted near a distal end of the probe, where the transducer has sufficient sensitivity, temporal resolution, and bandwidth to collect data from which a hemoglobin concentration can be derived and a cable connected to the transducer, where the probe is adapted to receive the distal end of the optical delivery system at its proximal end and situate the distal end of the optical delivery system flush with the housing at the distal end of the probe to provide appropriate irradiation conditions and acoustic contact between the blood vessel or tissue site and the acoustic transducer; and an electronic signal recording and processing system connected to the cable where the signal recording and processing system includes a digital processing unit or computer calculating a hemoglobin concentration from the recorded optoacoustic pressure profiles and amplitudes.