Biomedical applications of Jones-matrix tomography to polycrystalline films of biological fluids

Algorithms for reconstruction of linear and circular birefringence-dichroism of optically thin anisotropic biological layers are presented. The technique of Jones-matrix tomography of polycrystalline films of biological fluids of various human organs has been developed and experimentally tested. The coordinate distributions of phase and amplitude anisotropy of bile films and synovial fluid taken from the knee joint are determined and statistically analyzed. Criteria (statistical moments of 3rd and 4th orders) of differential diagnostics of early stages of cholelithiasis and septic arthritis of the knee joint with excellent balanced accuracy were determined. Data on the diagnostic efficiency of the Jones-matrix tomography method for polycrystalline plasma (liver disease), urine (albuminuria) and cytological smears (cervical cancer) are presented

Stokes-correlometry analysis of biological tissues with polycrystalline structure

Utilizing Stokes-correlometry analysis a new diagnostic approach has been introduced for quantitative assessment of polarization images of histological sections of optically anisotropic biological tissues with different morphological structures and physiological conditions. The developed approach is based on the quantitative assessment of coordinate and phase distributions of the Stokes vector of scattered light. A combined use of statistic, correlation, and fractal analysis is used for resolving variations in optical anisotropy of biological samples. The proposed combined application of the statistical, correlation, and fractal-based evaluates of spatial distributions of `single-point' polarization azimuth, ellipticity, and `two-point' Stokes vector parameters of polarization images of biological tissues histological sections demonstrates a high accuracy (Ac ≥ 90%) in monitoring of optical anisotropy variations within biological tissues

Recent progress in tissue optical clearing for spectroscopic application

This paper aims to review recent progress in optical clearing of the skin and over naturally turbid biological tissues and blood using this technique in vivo and in vitro with multiphoton microscopy, confocal Raman microscopy, confocal microscopy, NIR spectroscopy, optical coherence tomography, and laser speckle contrast imaging. Basic principles of the technique, its safety, advantages and limitations are discussed. The application of optical clearing agent on a tissue allows for controlling the optical properties of tissue. Optical clearing-induced reduction of tissue scattering significantly facilitates the observation of deep-located tissue regions, at the same time improving the resolution and image contrast for a variety of optical imaging methods suitable for clinical applications, such as diagnostics and laser treatment of skin diseases, mucosal tumor imaging, laser disruption of pathological abnormalities, etc

Recent progress in tissue optical clearing for spectroscopic application

This paper aims to review recent progress in optical clearing of the skin and over naturally turbid biological tissues and blood using this technique in vivo and in vitro with multiphoton microscopy, confocal Raman microscopy, confocal microscopy, NIR spectroscopy, optical coherence tomography, and laser speckle contrast imaging. Basic principles of the technique, its safety, advantages and limitations are discussed. The application of optical clearing agent on a tissue allows for controlling the optical properties of tissue. Optical clearing-induced reduction of tissue scattering significantly facilitates the observation of deep-located tissue regions, at the same time improving the resolution and image contrast for a variety of optical imaging methods suitable for clinical applications, such as diagnostics and laser treatment of skin diseases, mucosal tumor imaging, laser disruption of pathological abnormalities, etc

Blood flow visualization by means of laser speckle-contrast measurements under the conditions of nonergodicity

Abstract The influence of stationary structural inclusions in inhomogeneous strongly scattering media such as biotissues on the results of speckle-contrast measurements using temporal and spatial methods of image processing by means of laser speckle-contrast imaging is investigated. The limits of applicability of the method of laser speckle-contrast imaging are established in detail for the case in which ergodicity conditions are not fulfilled. Based on model experiments, it is demonstrated that an increase in the number of stationary scatterers relative to that of the dynamic ones in the sampling volume introduces substantial error into the results of spatial and temporal processing of speckle images for given exposure time of the detector. At the same time, analysis of spatial and temporal speckle contrasts, the values of the coefficient of speckle dynamics, along with the results of Monte-Carlo simulation of the sampling volume, revealed that the presence of a relatively thin, up to 30% of entire volume, static layer does not introduce considerable changes into the results of measurements by the method of laser speckle-contrast imaging. The exposure time of the camera, along with the number of frames used for image processing, can be varied and chosen individually for each experiment. The developed algorithms of spatial and temporal processing of images obtained by the method of laser speckle-contrast imaging were tested in the experiments on transcranial visualization of the cerebral blood flow of a mouse