Light propagation in tissues with controlled optical properties

Abstract

Theoretical and computer modeling approaches, such as Mie theory, radiative transfer theory, diffusion wave correlation spectroscopy, and Monte Carlo simulation were used to analyze tissue optics during a process of optical clearing due to refractive index matching. Continuous wave transmittance and forward scattering measurements as well as intensity correlation experiments were used to monitor tissue structural and optical properties. As a control, tissue samples of the human sclera were taken. Osmotically active solutions, such as Trazograph, glucose, and polyethylene glycol, were used as chemicals. A characteristic time response of human scleral optical clearing the range 3 to 10 min was determined. The diffusion coefficients describing the permeability of the scleral samples to Trazograph were experimentally estimated; the average value was D T Ϸ(0.9Ϯ0.5)ϫ10 Ϫ5 cm 2 /s. The results are general and can be used to describe many other fibrous tissues. © 1997

Correlation between collagen solubility and skin optical clearing using sugars

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