Diffuse-reflectance spectroscopy from 500 to 1060 nm by correction for inhomogeneously distributed absorbers

Optics Letters (Impact Factor: 3.29). 03/2002; 27(4):246-8. DOI: 10.1364/OL.27.000246
Source: PubMed


Diffuse-reflectance spectroscopy for measurement of the absorption and scattering coefficients of biological tissue produces reliable results for wavelengths from 650 to 1050 nm. Implicitly, this approach assumes homogeneously distributed absorbers. A correction factor is introduced for inhomogeneous distribution of blood concentrated in discrete cylindrical vessels. This factor extends the applicability of diffusion theory to lower wavelengths. We present measurements of in vivo optical properties in the wavelength range 500-1060 nm.

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Available from: Wim Verkruysse, Jan 09, 2015
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    • "are the specific absorption coefficients of oxygenized and deoxygenized blood, respectively. Ccor is the correction factor that accounts for flattening of spectral features resulting from the inhomogeneous distribution of blood in tissue and the confinement of blood in vessels [13,14]. For whole blood, the correction factor is given by: "
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    • "Here ck and ɛk are the concentration and extinction coefficient, respectively, of absorbing molecules (index k) such as oxyhemoglobin, deoxyhemoglobin, bilirubin, beta-carotene, lipids and water. Note that Eq. (10) may be modified to contain correction factors for the inhomogeneous distribution of absorbing molecules such as blood [26]. Application of Eqs. 8 and 9 to SFR spectra measured by each independent fiber diameter returns estimates of ck specific for each sampled fiber. "
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