Abstract
Introduction: The accurate estimation of time since death is of great value in medico-legal investigations of serious crimes. It was reported by several workers that measurement of the levels of potassium in the vitreous humour had a critical role in accurate prediction of time since death (within two hours). The present study was aimed to know the relation between sodium and potassium levels of vitreous humour and time since death.
Materials and Methods: A hospital based cross sectional observational study was carried out on 200 medico-legal cases at a tertiary care teaching hospital in western Rajasthan from 1st January 2016 to 31st December 2016. Vitreous fluid was collected from posterior chamber of eye by needle aspiration and detailed about the deceased i.e. age, sex, cause of death, exact time of death, time of sampling and corresponding Na+, and K+ level was recorded in a predesigned proforma.
Results: The present study showed linear correlation between rise in vitreous potassium (K+) ion concentration with increasing post-mortem interval (r=0.831). Rate of rise of vitreous potassium concentration was 0.29 meq/l/hr (Coefficient of regression=3.46 meq/l/hr). Sodium ion concentration in vitreous humour shows decline with increasing post-mortem interval but this decrease was statistically not significant (P>0.05).
Conclusion: Vitreous potassium (K+) ion concentration had a linear correlation with time since death. So, it can be used where estimation of time since death is difficult to know by other means in medico-legal cases.
Keywords: Medico-legal cases, post-mortem interval, vitreous humour, sodium and potassium level.
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Corresponding Author
Dr Navneet Sharma
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DOI: https://dx.doi.org/10.18535/jmscr/v6i7.32
