Experimental validation of a recently developed model for single-fiber reflectance spectroscopy

Significance: We recently developed a model for the reflectance measured with (multi-diameter) single-fiber reflectance (SFR) spectroscopy as a function of the reduced scattering coefficient [Formula: see text] , the absorption coefficient [Formula: see text] , and the phase function parameter [Formula: see text]. We validated this model with simulations. Aim: We validate our model experimentally. To prevent overfitting, we investigate the wavelength-dependence of [Formula: see text] and propose a parametrization with only three parameters. We also investigate whether this parametrization enables measurements with a single fiber, as opposed to multiple fibers used in multi-diameter SFR (MDSFR). Approach: We validate our model on 16 phantoms with two concentrations of Intralipid-20% ([Formula: see text] and [Formula: see text] at 500 nm) and eight concentrations of Evans Blue ([Formula: see text] to [Formula: see text] at 605 nm). We parametrize [Formula: see text] as [Formula: see text]. Results: Average errors were 7% for [Formula: see text] , 11% for [Formula: see text] , and 16% with the parametrization of [Formula: see text]; and 7%, 17%, and 16%, respectively, without. The parametrization of [Formula: see text] improved the fit speed 25 times (94 s to [Formula: see text]). Average errors for only one fiber were 50%, 33%, and 186%, respectively. Conclusions: Our recently developed model provides accurate results for MDSFR measurements but not for a single fiber. The [Formula: see text] parametrization prevents overfitting and speeds up the fit.