Post-Mortem Interval Estimation Using Polycrystalline Cerebrospinal Fluid Films Two-Dimensional Cartography Of Mutual Laser Polarization Distribution Levels

Post-mortem interval estimation is one of the most important issues in forensic practice. Optical diagnostic methods of biological tissue structure assessment are perspective in this area.The objects of investigation are polycrystalline films of cerebrospinal fluid, taken from 64 corpses with accurately known times of death and 15 healthy volunteers.The method of two-dimensional stokes-polarimetric mapping of distributions of a complex degree of mutual polarization with spatial-frequency filtration of microscopic images of cerebrospinal fluid films in the time monitoring of post-mortem changes in optical manifestations of polycrystalline networks has been tested in order to estimate the post-mortem interval. The most sensitive post-mortem changes in the optical manifestations of polycrystalline cerebrospinal fluid networks are revealed - statistical moments of the third and fourth orders that characterize the asymmetry and the excess (severity of the peak) of the distributions of values of the complex degree of mutual polarization of large-scale components of cerebrospinal fluid polycrystalline films microscopic images.An interval of 48 hours with the accuracy of the post-mortem interval estimation in ± 30 minutes were established by the method of two-dimensional mapping of distributions of the values of a complex degree of mutual polarization of large-scale component of cerebrospinal fluid films microscopic images.