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Perturbation theory for diffuse light transport in complex biological tissues.

M R Ostermeyer·S L Jacques
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Abstract

A perturbation theory for the forward problem of optical transport in turbid media is developed. It is applicable to media with scattering and absorption in homogeneties and steady-state and modulated light. Absorbing perturbations can be described by a volume distribution of virtual sources that primarily causes a monopole perturbation light field. Scattering objects have an additional contribution that, in the limiting case of sharply bounded objects, is represented by a surface distribution of virtual sources and causes a dipolelike perturbation pattern. Using the concept of virtual sources, we discuss a possible ambiguity between the perturbations from scattering and absorbing inhomogeneities and the implications for the source-detector placement in inverse problems. We show that the surface effects due to sharp boundaries of scattering objects pose both a numerical problem and a chance to improve the resolution of inverse algorithms.

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AbsorptionAlgorithmsLightScattering, RadiationSolutionsJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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M R Ostermeyer, S L Jacques. 1997. Perturbation theory for diffuse light transport in complex biological tissues.. https://doi.org/10.1364/josaa.14.000255

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