Post-mortem interval estimation by laser-induced fluorescence of polycrystalline cerebro-spinal fluid films images

Abstract

There are many new optical diagnostic methods (photometric, polarization and correlation techniques) of biological tissue structure assessment, which are the most perspective in post-mortem interval determination.
 The purpose of the work. Development and testing of the two-dimensional Stokes-polarimetric mapping of biological layers own fluorescence to evaluate accuracy of the post-mortem interval (PMI) assessment using statistical analysis of postmortem changes dynamics of the coordinate distributions values of polycrystalline films of liquor (PFL) images laser-induced fluorescence polarization intensity (LIFPI).
 Materials and methods. Objects of investigation are PFL, taken in 72 corpses with accurately known time of death and 20 healthy volunteers. The cause of the death was cardiovascular accident. Coordinate distributions of LIFPI image values were determined for each sample of PFL in the optical arrangement of the Stokes polarimeter in short-range spectrum of optical radiation.
 The value of statistical points 1 - 4 th order was perfomed for each two-dimensional distribution of PFL images LIFPI values. Statistical processing of the calculated values of set of points that characterize the LIFPI distributions was carry out. The depending on the time change of the most sensitive points of statistical values were built.
 Results and conclusions. Two-dimensional Stokes-polarimetric mapping distributions LIFPI of PFL images may be used in determination of the PMI. Statistical points of the first and fourth order are the most sensitive PFL optical values to evaluate postmortem changes by short-range fluorescence.