[Study on relationship between changes of geometry parameters in human spleen nuclei and the postmortem interval].

ABSTRACT

OBJECTIVE: Using computer image-analyze technique (CIAT) to study changes of geometry parameters in human spleen nuclei and seek a new experimental method to deduce the estimation the postmortem interval (PMI). METHODS: 31 cadavers that known accurate PMI, sampled and smeared respectively every hour within the first 36 hours after death, fixed with cold Carony fixation, stained by Feulgen-van's method, and measured 5 geometry parameters using the image-analyze instrument including Area (A), Mean-Dia (MD), Average Diameter (AD), perimeter (P), Index of density (ID). RESULTS: A, MD, AD and P in the human spleen nuclei have no correlation with the PMI. But ID rose regularly with the prolongation of PMI in 36 hours. There was a definite correlation between ID and the PMI, r=0.983, linear regression equation with PMI (hours) as the dependent variable was calculated for ID. CONCLUSION: Geometry parameter ID was proved to be preferable indexes for estimation of PMI in 36 hours.