We have investigated the distribution of photon path lengths in turbid media
by comparison of the measurements of light propagation in tissue phantom
with the results of Monte Carlo simulation. When this distribution is known
then the inverse problem of light propagation can be solved to determine the
absorption coefficient with better accuracy than by the mean free path
approximation. We have used 4 wavelength laser spectrometer for real
time in vivo measurements of Hb and HbO2 in living tissue. The operation of
the spectrometer was tested by recording and interpreting the dynamics of
blood parameters during different physiological tests. Different ways of
increasing the accuracy of measurements are discussed.
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