Assessment of tissue polarimetric properties using Stokes polarimetric imaging with circularly polarized illumination

Abstract

Tissue-depolarization and linear-retardance are the main polarization characteristics of interest for bulk tissue characterization, and are normally interpreted from Mueller polarimetry. Stokes polarimetry can be conducted using simpler instrumentation and in a shorter time. Here, we use Stokes polarimetric imaging with circularly polarized illumination to assess the circular-depolarization and linear-retardance properties of tissue. Results obtained were compared with Mueller polarimetry in transmission and reflection geometry, respectively. It is found that circular-depolarization obtained from these 2 methods is very similar in both geometries, and that linear-retardance is highly quantitatively similar for transmission geometry and qualitatively similar for reflection geometry. The majority of tissue circular-depolarization and linear-retardance image information (represented by local image contrast features) obtained from Mueller polarimetry is well preserved from Stokes polarimetry in both geometries. These findings can be referred to for further understanding tissue Stokes polarimetric data, and for further application of Stokes polarimetry under the circumstances where short acquisition time or low optical system complexity is a priority, such as polarimetric endoscopy and microscopy.

Comparative study of the imaging contrasts of Mueller matrix derived parameters between transmission and backscattering polarimetry

“…3(a) ) is slightly more prominent than that in backscattering image (1.5%, Fig. 3(b) ), which was also observed in our recent study [ 39 ]. However both in forward and backward measurements, the differences of parameter Δ between connective tissues and hepatic lobules are slight, indicating that the depolarization abilities of the connective tissues and hepatic lobules in this porcine liver sample are close.…”

“…In this coordinate system there is an opposite sign of Mueller matrix element m24 or m42 on Figs. 2(a) and 2(b) [ 39 ]. The sign convention does not change the values of MMT and MMPD parameters.…”

“…The very similar retardance value distributions here in backward and forward measurements suggest the similar average optical paths for transmitted and backscattered photons of the 40 µm porcine liver tissue sample. When the thickness of porcine liver tissue sample increases, the average retardance value in backward measurement becomes larger than that in forward measurement [ 39 ], indicating longer average optical paths for backscattered photons. However, the contrasts of retardance images are still similar for forward and backward measurements.…”

“…In this study, we take porcine liver and human breast carcinoma tissues as the experimental samples. In our previous studies it is found that porcine liver contains both anisotropic connective tissues and isotropic hepatic lobule tissues, which have very different polarization properties [ 32 , 39 ]. Also, the distribution change of fibrous structures is an important feature of human breast carcinoma samples in different progression stages [ 6 , 22 ].…”

Polarisation optics for biomedical and clinical applications: a review

“… a Stokes vector based approaches: (i) DOP, DOLP and DOCP 2 – 5 ; (ii) Stokes vector projection approach 158 ; (iii) Stokes vector location approach 159 ; (iv) Dipole orientation differentiation approach. Polarisation angle (PA) and intensity are used as main parameters 154 , 155 .…”