BACKSCATTERING OF LIGHT BY RED-CELL SUSPENSIONS

It is possible in principle to measure the blood content and oxygenation of the skin and superficial tissues by studying the backscattering of light from such tissues. It is normally assumed that photodiffusion theory may be used to relate reflectance to the optical properties of the tissue, and in order to test this assumption we have made in vitro measurements of the backscattered light from blood over a wide range of haematocrits. The experimental results are consistent with the theory, except over distances comparable with the photon mean free path in the blood. © 1979 IFMBE.