Analysis of diffuse reflectance spectroscopy by means of Bayesian inference and separation of the parameters for scattering strength and spectral dependence of the scattering. Issue 12 (23rd September 2021)

• Record Type: Journal Article
• Authors: Hohmann, Martin; Karabayir, Ayse; Herzler, Paul; Späth, Moritz; Klämpfl, Florian; Schmidt, Michael
• Is Part Of: Journal of biophotonics. Volume 14:Issue 12(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-09-23
• Subjects: Bayesian inference -- diffuse reflectance spectroscopy -- DRS -- reduced scattering -- scattering; Photonics -- Periodicals; Optical materials -- Periodicals; Optics -- Periodicals; Medical instruments and apparatus -- Periodicals; 621.3605
• DOI: 10.1002/jbio.202100205
• Languages: English
• ISSNs: 1864-063X

Abstract

Abstract: For many applications in tissue optics, knowledge of the scattering coefficient or at least the reduced scattering coefficient is essential. In addition, its spectral dependence is also an important feature, as this provides information about scatterer sizes. While the characterization of the spectral dependence should be a simple fit, experimental results show strong fluctuations even for the same tissue type. For in‐vivo measurements, this problem is even greater. Therefore, it is the aim of this study to analyze the instabilities of the scattering characterizations and find a solution for it by means of Bayesian inference. In this study, this behavior is investigated using the example of diffuse reflectance spectroscopy. It can be shown that the currently used fitting functions are unstable for the fitting as both parameters for characterizing the reduced scattering coefficient describe the spectral dependence as well as the scattering strength. However, by a simple coordinate transform, a stable mathematical description of the scattering is derived. By the fact that a posteriori probability of the reduced scattering coefficient narrows down significantly with the Bayesian inference, the new fitting function is verified. Abstract : Scattering has a strong spectral dependence. While its characterization should be a simple fit, experimental results show strong fluctuations even for the same tissue type. These instabilities are analyzed by means of Bayesian Inference. By a simple coordinate transform, which separates scattering strength and scatterer size effects, a stable mathematical description of the scattering is derived. Thus, the resulting a posteriori probability of the reduced scattering coefficient narrows down significantly.