Measurement of the reduced scattering coefficient of turbid media using single fiber reflectance spectroscopy: fiber diameter and phase function dependence

Abstract

This paper presents a relationship between the intensity collected by a single fiber reflectance device ( R _SF ) and the fiber diameter ( d _fib ) and the reduced scattering coefficient ( ${\mu }_s^{\prime }$ ) and phase function ( p( θ)) of a turbid medium. Monte Carlo simulations are used to identify and model a relationship between R _SF and dimensionless scattering ( ${\mu }_s^{\prime }{d}_{\mathit{\text{fib}}}$ ). For ${\mu }_s^{\prime }{d}_{\mathit{\text{fib}}}\hspace{0.17em}>\hspace{0.17em}10$ we find that R _SF is insensitive to p( θ). A solid optical phantom is constructed with ${\mu }_s^{\prime }\hspace{0.17em}\approx \hspace{0.17em}220\hspace{0.17em}{\text{mm}}^{-1}$ and is used to convert R _SF of any turbid medium to an absolute scale. This calibrated technique provides accurate estimates of ${\mu }_s^{\prime }$ over a wide range ([0.05 – 8] mm ⁻¹) for a range of d _fib ([0.2 – 1] mm).