Complementary analysis of Mueller-matrix images of optically anisotropic highly scattering biological tissues

Abstract

Background: Using optical techniques for tissue diagnostics (so-called 'optical biopsy') has been a subject of extensive research for many years. Various groups have been exploring different spectral and/or imaging modalities (e.g. diffuse reflectance spectroscopy, autofluorescence, Raman spectroscopy, optical coherence tomography (OCT), polarized light microscopy, etc.) for biomedical applications. In this paper, we report on using multi-wavelength imaging Mueller polarimetry combined with an appropriated image post-processing for the detection of tissue malignancy. Methods: We investigate a possibility of complementary analysis of Mueller matrix images obtained for turbid tissue-like scattering phantoms and excised human normal and cancerous colorectal tissue samples embedded in paraffin. Combined application of correlation, fractal and statistical analysis was employed to assess quantitatively the polarization-inhomogeneous scattered fields observed at the surface of tissue samples. Results: The combined analysis of the polarimetric images of paraffin-embedded tissue blocks has proved to be an efficient tool for the unambiguous detection of tissue malignant transformation. A fractal structure was clearly observed at spatial distributions of depolarization of light scattered in healthy tissues in a visible range of spectrum, while corresponding distributions for cancerous tissues did not show such dependence. We demonstrate that paraffin does not destroy a fractal structure of spatial distribution of depolarization. Thus, the loss of fractality in spatial distributions of depolarization for cancerous tissue is related to the structural changes in the tissue sample induced by cancer itself and, therefore, may serve as a marker of the disease. Conclusion: The obtained results emphasize that a combined use of statistical, correlation and fractal analysis for the Mueller-matrix image post-processing is an effective approach for an assessment of variations of optical properties in turbid tissue-like scattering media and biological tissues, with a high potential to be transferred to clinical practice for screening cancerous tissue samples.

The use of Stokes-Mueller polarimetry for assessment of amyloid-β progression in a mouse model of Alzheimer’s disease

“…The matrices were diagonal for all 21 measured samples (3 samples for each of 7 stages of the disease), which means that paraffin-embedded blocks of mouse brain tissue acted as a partial depolarizer and did not exhibit any anisotropy of amplitude or phase. The spatial distributions of total depolarization parameter ∆= 1 − 22+ 33+ 44 3 were analyzed using statistical moments of 1 st to 4 th order, as it was done in previously published works 13,14 . The obtained trends of the 1 st to 4 th statistical moments (mean value, standard deviation, skewness and kurtosis) are shown in Figure 4 According to the obtained results, the statistical moments of the 1 st and 2 nd order of the distributions of total depolarization at different stages of the disease do not exhibit noticeable changes with the disease progression.…”

Analysis of tissue microstructure with Mueller microscopy: logarithmic decomposition and Monte Carlo modeling

“…1 It has been shown that Mueller matrix formalism is a powerful tool in the study of biological samples. [2][3][4] This phenomenological approach describes the interaction of polarized light with a sample using a model of "equivalent optical circuit" built from the basic optical elements-diatenuators, retarders, and depolarizers. The extended toolkit of various Mueller matrix decompositions (data processing algorithms exploring nonlinear compression of a set of real values of 4 × 4 Mueller matrices) is available for data analysis and characterization of tissue optical properties.…”

Mapping of retardance, diattenuation and polarizance vector on Poincare sphere for diagnosis and classification of cervical precancer

“…Various imaging techniques, primarily based on transmission, absorption, reflection, spontaneous emission and scattering in light‐tissue interactions, have shown to be responsive to a number of subtle alterations in various diseased tissue. Mueller matrix (MM) polarimetric imaging based on the acquisition of 16 images has shown tremendous potential in precancer detection since the last decade and is best suited for a complete characterization of the biological specimen . These MM images are further processed to extract the essential optical parameters, namely, diattenuation, retardation and depolarization through Lu‐Chipman decomposition method .…”