Quantitative MRI molecular imaging in the evaluation of early post mortem changes in muscles. A feasibility study on a pig phantom

Estimating early postmortem interval EPI is a difficult task in daily forensic activity due to limitations of accurate and reliable methods. The aim of the present work is to describe a novel approach in the estimation of EPI based on quantitative magnetic resonance molecular imaging qMRMI using a pig phantom since post mortem degradation of pig meat is similar to that of human muscles. On a pig phantom maintained at 20 degree, using a 1.5 T MRI scanner we performed 10 scans, every 4 hours, monitoring apparent diffusion coefficient ADC, fractional anisotropy FA, magnetization transfer ration MTR, tractography and susceptibility weighted changes in muscles until 36 hours after death. Cooling of the phantom during the experiment was recorded. Histology was also obtained. Pearson's Test was carried out for statistical correlation. We found a significative statistical inverse correlation between ADC, FA, MT and PMI. Our preliminary data shows that post mortem qMRMI is a potential powerful tool in accurately determining EPI and is worth of further investigation.