Speckle-contrast imaging of pathological tissue microhemodynamics at optical clearing

The study of blood microcirculation is one of the most important problems of the medicine. This is caused by the fact that many diseases, such as cardio-vascular diseases, atherosclerosis, diabetes, chronic venous insufficiency, oncology diseases, cause functional and morphological changes of microcirculation of blood flow. The results of experimental study of changes of blood microcirculation of pancreas in rats with diabetes measured by using Laser Speckle Contrast Imaging (LSCI) at application of optical clearing agents are presented. Laser speckle contrast techniques are based on the spatial and temporal statistics of the speckle pattern, calculating of contrast of time-averaged dynamic speckles in dependence on the exposure time at the registration of the speckle-modulated images. In research, 28 Wistar rats weighing 300-500 g were used. Alloxan induced animal model of diabetes was explored. The influence of solution of glycerol, PEG-300 was investigated. Application of 70%-aqueous glycerol solution demonstrates 50%-decrease of blood flow velocity in the group of diabetic animals, to 10th min blood flow velocity was completely restored. Blood flow in the control group almost stopped, to 10 min has not recovered. Application of solution of PEG-300 demonstrates 25%- decrease of blood flow in the group of diabetic animals. Blood flow in the control group show 65%-decrease of blood flow. The results obtained at the study of blood microcirculation disorders of pancreas in diabetes show that diseases development in animals causes changes in the microcirculatory system and application of optical clearing agents demonstrates changes in vascular permeability in conditions of development of pathologies