Patent ID: 6473632
Filing Date: 2002-10-29
Classification: A61B,G01J,G01N

Abstract:
A method for measuring total concentration of a chromophore having at least two functional states in tissue, including:providing stored relationship data representative of lines or curves which characterize the relationship between second-derivative absorbance values at a first chromophore-absorbing wavelength and total concentration of the chromophore in tissue at constant functional state portion values; receiving a first second-derivative absorbance value from a tissue being analyzed at the first chromophore-absorbing wavelength; receiving functional state portion data representative of the value of the functional state portion of the chromophore in the tissue being analyzed; and generating data representative of the total concentration of the chromophore in the tissue being analyzed as a function of the line or curve of constant functional state portion of the chromophore associated with the received functional state portion data and the received first second-derivative absorbance value.