Quantitative correlation between light depolarization and transport albedo of various porcine tissues

Abstract

Abstract. We present a quantitative study of depolarization in biological tissues and correlate it with measured optical properties (reduced scattering and absorption coefficients). Polarized light imaging was used to examine optically thick samples of both isotropic (liver, kidney cortex, and brain) and anisotropic (cardiac muscle, loin muscle, and tendon) pig tissues in transmission and reflection geometries. Depolarization (total, linear, and circular), as derived from polar decomposition of the measured tissue Mueller matrix, was shown to be related to the measured optical properties. We observed that depolarization increases with the transport albedo for isotropic and anisotropic tissues, independent of measurement geometry. For anisotropic tissues, depolarization was higher compared to isotropic tissues of similar transport albedo, indicating birefringence-caused depolarization effects. For tissues with large transport albedos (greater than ∼0.97), backscattering geometry was preferred over transmission due to its greater retention of light polarization; this was not the case for tissues with lower transport albedo. Preferential preservation of linearly polarized light over circularly polarized light was seen in all tissue types and all measurement geometries, implying the dominance of Rayleigh-like scattering. The tabulated polarization properties of different tissue types and their links to bulk optical properties should prove useful in future polarimetric tissue characterization and imaging studies.

Characterizing microstructures of cancerous tissues using multispectral transformed Mueller matrix polarization parameters

“…8(b) that as the value of birefringence increases, the baseline of the spectra of the parameter b decreases. This is because that increasing birefringence can induce stronger depolarization effectively [32,33], resulting in a smaller value of the parameter b which is negatively correlated with the depolarization. …”

Narrow band 3 × 3 Mueller polarimetric endoscopy

“…Photons that penetrate deeper have longer flight times and are more likely to be scattered multiple times with their polarization randomized. Thus, depolarization in turbid media has been applied as a gating technique to separate singly scattered, specularly reflected and multiply scattered light for the following scenarios: i) to enhance the image contrast near to the tissue surface [1]; ii) to extract single elastic scattering spectra from diffuse backgrounds for cell nucleus and cytoplasm size characterization [2,3]; iii) to improve image quality by removing specular reflections [4]: iv) to select well-defined subsurface volumes in a turbid medium [5]; v) to reveal features at depth such as pigmentation and vessels when detecting via cross polarizers [6]; vi) to correlate with tissue absorption and scattering [7]; and vii) for disease diagnosis [8][9][10]. In addition, a number of constituents in tissue including structural proteins like collagen, and chiral molecules like glucose, also manifest birefringence and optical rotation which can contribute to the detection of tissue abnormalities such as osteoarthritis, thermal injury and cancer [10][11][12][13][14][15].…”

Quantification of glucose and glycerol diffusion in myocardium

“…6 Along with conventional methods, many optical methods are rapidly developing to be used in nearest future for diagnostics and therapeutics in cardiology. [7][8][9][10] However, in spite of numerous bene¯ts in the use of optical methods in medicine there are some serious disadvantages. One of the problems is connected with the transport of the light beam through the turbid tissues to the target region of the search or treatment.…”