Abstract

After analytical expressions for the time-resolved reflectance are introduced from the diffusion approximation under the three most commonly used boundary conditions, a novel algorithm is demonstrated for determining the reduced scattering and the absorption coefficients from time-resolved reflectance (or backscatter) measurements at two positions on the surface of biotissue. The algorithm is straightforward and fast and involves only some simple mathematical operations, avoiding complicated iterative nonlinear fitting to the time-resolved curve. The derived reduced scattering coefficient is not affected by whatever boundary condition is applied. The algorithm was verified with time-resolved data from the Monte Carlo model. Both a semi-infinite medium and a turbid slab medium were tested. In contrast to the nonlinear fitting method, this algorithm allows both the scattering and the absorption coefficients to be determined to a high accuracy.

© 1998 Optical Society of America

Investigation of two-layered turbid media with time-resolved reflectance

Alwin Kienle, Thomas Glanzmann, Georges Wagnières, and Hubert van den Bergh
Appl. Opt. 37(28) 6852-6862 (1998)

Noninvasive determination of the optical properties of two-layered turbid media

Alwin Kienle, Michael S. Patterson, Nora Dögnitz, Roland Bays, Georges Wagnières, and Hubert van den Bergh
Appl. Opt. 37(4) 779-791 (1998)

Accuracy of the diffusion approximation in determining the optical properties of a two-layer turbid medium

George Alexandrakis, Thomas J. Farrell, and Michael S. Patterson
Appl. Opt. 37(31) 7401-7409 (1998)

Improved solutions of the steady-state and the time-resolved diffusion equations for reflectance from a semi-infinite turbid medium

Alwin Kienle and Michael S. Patterson
J. Opt. Soc. Am. A 14(1) 246-254 (1997)

Determination of tissue optical properties from diffuse reflectance profiles by multivariate calibration

Jan S. Dam, Peter E. Andersen, Torben Dalgaard, and Paul Erik Fabricius
Appl. Opt. 37(4) 772-778 (1998)