Cushman Darby & Cushman IP Group of Pillsbury Madison & Sutro LLP
인용정보
피인용 횟수 : 33인용 특허 : 0
초록 ▼
A spectrometric technique is described for quantitatively determining the change in concentration of a substance which is contained in a medium which both absorbs and scatters spectroscopically interrogated radiation, and in particular to the specific case in which the change in concentration of the substance occurs in one spatially distinct region of the medium. The medium includes a plurality of such regions displaying potentially different absorption and scattering properties to the radiation. Specific applications are disclosed involving the noninvas...
A spectrometric technique is described for quantitatively determining the change in concentration of a substance which is contained in a medium which both absorbs and scatters spectroscopically interrogated radiation, and in particular to the specific case in which the change in concentration of the substance occurs in one spatially distinct region of the medium. The medium includes a plurality of such regions displaying potentially different absorption and scattering properties to the radiation. Specific applications are disclosed involving the noninvasive determination of changes in concentration of the substances oxyhemoglobin and deoxyhemoglobin and/or changes in the redox state of the substance cytochrome oxidase within the brain or skeletal muscle, and in cases where the brain or skeletal muscle is interrogated by radiation in the near-infrared part of the electromagnetic spectrum through intervening surface tissues, i.e., cortical bone or adipose tissue, where it may be assumed that no changes of concentration of said substances occur within said surface tissues.
대표 청구항 ▼
[ What is claimed is:] [1.] A method of determining a change in concentration of at least one subject substance in one region of a plurality of regions of a medium, the one region being adaptable to both absorb and scatter radiation, substantially all of the change in concentration of the at least one subject substance in the medium occurring in the one region of the plurality of regions, said method comprising:introducing into and propagating through the medium first interrogating radiation which is penetrative of the medium;detecting the first interrog...
[ What is claimed is:] [1.] A method of determining a change in concentration of at least one subject substance in one region of a plurality of regions of a medium, the one region being adaptable to both absorb and scatter radiation, substantially all of the change in concentration of the at least one subject substance in the medium occurring in the one region of the plurality of regions, said method comprising:introducing into and propagating through the medium first interrogating radiation which is penetrative of the medium;detecting the first interrogating radiation which has propagated through the medium and determining a total differential pathlength traversed by the first interrogating radiation in the medium;identifying a plurality of reference substances, each of which possesses a sufficiently distinct specific absorption coefficient to interrogating radiation and a known concentration in each region of the plurality of regions of the medium, the concentration of each of the plurality of reference substances in the one region being different from the concentration of the same reference substance in each of the other regions of the plurality of regions of the medium;for each reference substance of the plurality of reference substances, introducing into and propagating through the medium second interrogating radiation which is penetrative of the medium, detecting and spectrometrically analyzing the second interrogating radiation which has propagated through the medium, and determining an intensity of a spectral absorption feature of the reference substance;determining a partial differential pathlength of the one region by simultaneously solving a first linearly independent equation for each reference substance and a second equation, the first and second equations respectively being expressed as follows: ]EQU5 ] where a.sub.i is the intensity of the spectral absorption feature of the reference substance;C.sub.ij is the known concentration of the reference substance in the region j of the plurality of regions;.di-elect cons..sub.i is the absorption coefficient of the reference substance;Z.sub.T is the total differential pathlength;Z.sub.j is a partial differential pathlength of the radiation in the region j of the plurality of regions; andn is a total number of regions in the plurality of regions;introducing into and propagating through the medium third interrogating radiation which is penetrative of the medium;detecting and spectrometrically analyzing the third interrogating radiation which has propagated through the medium and determining a change in an intensity of a spectral feature of the at least one subject substance; andobtaining the change in concentration of the at least one subject substance in the one region of the plurality of regions of the medium by solving a third equation, the third equation being expressed as follows: EQU C=A/(.di-elect cons..multidot.Z) reC is the change in concentration of the at least one subject substance in the one region of the plurality of regions of the mediumA is the change in the intensity of the spectral feature of the at least one subject substance;.di-elect
