DIAGNOSTICS OF THE DEGREE OF BLOOD LOSS BY THE METHOD OF STATISTICAL ANALYSIS OF MAPS OF OPTICAL ACTIVITY OF THE POLYCRYSTALLINE COMPONENT OF BIOLOGICAL TISSUES AND FLUIDS

The research was conducted to create a reliable and accurate approach to determining the volume of blood loss, which will allow forensic experts to increase objectivity and accuracy in establishing the causes and circumstances of death, as well as assessing the degree of traumatic injuries, and will help ensure more reliable examination results in forensic practice.          The aim of the work is to develop and evaluate the effectiveness of a method for differential diagnosis of the degree of blood loss in corpses using statistical analysis of optical activity maps of the polycrystalline component of biological tissues and fluids.          Material and methods. The study material was brain, kidney and blood samples (n=124) from corpses aged 18 to 60 years with a previously known blood loss volume from 0mm3 to 2500mm3. The study was conducted using the method of multiparametric differential Muller matrix tomography, which allows detecting changes in the structure of polycrystalline elements of biological tissues at different degrees of blood loss. Calculation of digital values was performed using a laser polarimeter of a standard scheme, further statistical processing was performed using MS® Excel® 2010™ and Statistica® 7.0 software. Results. For all studied biological samples, the method demonstrates high sensitivity in the range of blood loss volume from 0 мм³ to 1500 мм³ with an accuracy level of 86%-92%. Within the range of blood loss volume from 2000 мм³ to 2500 мм³ the accuracy of the method decreases to 56%-68%. The maximum level of accuracy is achieved for statistical parameters of kidney samples (SM4↔86%-92%), brain (SM4↔86%-90%) and blood films (SM2↔90%-92%), which characterize the Muller matrix maps of circular birefringence. Conclusions. Based on the conducted study, the high efficiency of the multiparametric Muller matrix differential tomography method in determining the degree of blood loss within the volume of lost blood ∆V=0mm3÷1500mm3 was established. The obtained results demonstrate that this method allows for an objective assessment of structural changes in biological tissues and fluids caused by blood loss. This makes it a unique tool for objectively determining the volume of blood loss.