Measurement of tissue scattering properties using multi-diameter single fiber reflectance spectroscopy: in silico sensitivity analysis

Multiple diameter single fiber reflectance (MDSFR) measurements of turbid media can be used to determine the reduced scattering coefficient (mu(s)') and a parameter that characterizes the phase function (gamma). The MDSFR method utilizes a semi-empirical model that expresses the collected single fiber reflectance intensity as a function of fiber diameter (d(fiber)), mu(s)', and gamma. This study investigated the sensitivity of the MDSFR estimates of mu(s)' and gamma to the choice of fiber diameters and spectral information incorporated into the fitting procedure. The fit algorithm was tested using Monte Carlo simulations of single fiber reflectance intensities that investigated biologically relevant ranges of scattering properties (mu(s)' is an element of [0.4-4]mm(-1)) and phase functions (gamma is an element of [1.4-1.9]) and for multiple fiber diameters (d(fiber) is an element of [0.2-1.5] mm). MDSFR analysis yielded accurate estimates of mu(s)' and gamma over the wide range of scattering combinations; parameter accuracy was shown to be sensitive to the range of fiber diameters included in the analysis, but not to the number of intermediate fibers. Moreover, accurate parameter estimates were obtained without a priori knowledge about the spectral shape of gamma. Observations were used to develop heuristic guidelines for the design of clinically applicable MDSFR probes. (C) 2011 Optical Society of America