COMPARATIVE ANALYSIS OF THE EFFECTIVENESS OF USING HISTOLOGICAL AND PHYSICAL-OPTICAL METHODS OF INVESTIGATING OF THE TIME OF HEMORRHAGE FORMATION IN THE SUBSTANCE OF THE HUMAN BRAIN

Abstract

Important attention in forensic medical practice is given to the solution of issues that arise during the examination in thecase of traumatic brain injury (TBI), as this type of injury leads to high mortality and disability. Conducting an autopsy of thebody of the deceased, whose death occurred from a TBI, there are cases when the injury occurs as a result of a fall of a person who previously developed a cerebral infarction, and sometimes vice versa. In this case, it is important to accurately verify the primary cause of death, therefore, timely and objective determination of the time of formation of a hemorrhage in the human brain is necessary.The purpose and tasks of the research. To evaluate the possibility of detecting time of formation of a hemorrhage of traumatic and non-traumatic genesis by the generally accepted histological method and polarization phase microscopy, and to compare their eff ectiveness.Research materials and methods. For the study, human brain samples were selected from 140 deceased individuals whosedeaths occurred between 1 and 3 days after the onset of bleeding, according to medical records. As a control group, human brain samples were selected from 40 individuals who died of coronary heart disease. Light microscopy was performed by preliminary staining of histologic specimens according to the Perls method. Phase polarization tomography of the samples was performed using a Stokes polarimeter.Research results. Stained human brain preparations of the experimental and control groups were examined and analyzedand it was found that hemosiderin was not present in all experimental samples (only in 31 out of 40 samples were present). It was not possible to establish the corresponding time dependences of the age of the formation of hemorrhages, regardless of the genesis, since the random appearance of the pigment in the experimental samples is noted at diff erent time intervals. Analytical processing of the results of the statistical processing of the topographic structure of tomograms of the anisotropy of linear dichroism of the fi brillar networks of samples of the deceased from the experimental and control groups revealed a wider time range of sensitivity of this method to destructive changes in nervous tissue, in comparison with the polarimetric methods used in previous studies. As a result, there is an accelerated temporal decrease in the absolute values and the range of dispersion of the anisotropy of linear dichroism value with increasing time since the formation of hemorrhage.Conclusions. Polarization- phase microscopy has shown a signifi cant advantage in its use in comparison with the goldstandard – the Perls’ staining method for determining the time of hemorrhage formation in the human brain.