TISSUE MODULATION PROCESS FOR QUANTITATIVE NONINVASIVE IN VIVO SPECTROSCOPIC ANALYSIS OF TISSUES

摘要

Methods are provided for noninvasively measuring blood volumeand analyte concentration and for obtaining spectroscopic informationrelating to immobile tissues, such as skin. One method is fordetermining concentration of an analyte, such as glucose, in blood ofa subject. The method comprises irradiating a region of tissue, such asa fingertip, of the subject with a light source; collecting fluorescencespectra by the region of tissue, the quantity of fluorescence spectra beingindicative of blood volume; and collecting Raman spectra emittedby the region of tissue at a wavelength range that corresponds to theanalyte. The method further comprises dividing the collected Ramanspectra by the collected fluorescence spectra to obtain a number proportionalto the concentration of analyte per unit blood volume. Themethod can further comprise determining the integral of net collectedspectra, net collected spectra being a difference between spectra collectedwhile the region of tissue is in a blood-replete state and spectracollected while the region of tissue is in a blood-depleted state. Themethod can further comprise enhancing the spectra collected by performingadjacent averaging smoothing operations. Blood volume in aregion of tissue for spectroscopic measurement can be modulated byapplying an ultrasonic transducer to the region of tissue, and also byapplying a tourniquet.