Differences in the kinetics of optical clearing of healthy and diabetic head tissues

Background and Objectives: Optical differentiation of pathologies is a promising tool for biomedical diagnostics, primarily due to its non-invasiveness and ease of implementation. The values of optical parameters andthe kinetics oftheir changes differ in healthy and pathological tissues due to changes in the tissue structure. In diabetes mellitus, such changes are especially noticeable. This requires detailed studies and the development of quantitative criteria for differentiating pathological (glycated) tissues. Materials and Methods: This paper presents an ex vivo experimental study of the optical and geometric parameters of rat head tissue samples under the action of an immersion liquid in the form of an aqueous 70$\%$ glycerol solution. Results: Optical and volumetric-weight characteristics were measured for rat head tissue samples (scalp skin, skull bone, dura mater, gray and white matter of the brain) in health and in model diabetes mellitus. Collimated transmission spectra of tissue samples were measured in the wavelength range of 450–900 nm. Conclusion: Analysis of optical transmittance kinetics over time up to 60 minutes has shown that all types of head tissue in diabetic rats exhibited impaired diffusion of test glycerol molecules compared to healthy rats.