Postmortem Temporal Changes in Liver and Spleen Stiffness: Evaluation with Shear Wave Elastography in a Rat Model

Area of Science:

• Biomedical Engineering
• Forensic Science
• Pathology

Background:

• Tissue stiffness and organ morphology changes postmortem are crucial for forensic pathology.
• Shear wave elastography (SWE) is a non-invasive tool for tissue stiffness assessment.
• The temporal progression of postmortem tissue elasticity changes requires further investigation.

Purpose of the Study:

• To investigate temporal changes in liver and spleen stiffness using SWE postmortem.
• To evaluate the predictive potential of elastographic parameters for postmortem interval estimation.

Main Methods:

• Twelve rats underwent postmortem liver and spleen measurements (dimensions and SWE) at multiple time points (0-36 h).
• Statistical analysis included repeated measures ANOVA and ROC curve analysis.
• Binary logistic regression assessed the predictive accuracy of SWE parameters.

Main Results:

• Liver and spleen stiffness significantly declined postmortem (p < 0.001).
• Organ dimensions showed an initial increase followed by a decrease.
• Spleen SWE (AUC=0.917) and liver SWE (AUC=0.845) were strong predictors of early postmortem interval.

Conclusions:

• Postmortem liver and spleen stiffness progressively decline, with organ dimensions exhibiting a biphasic pattern.
• Elastographic parameters, particularly SWE, accurately predict early postmortem intervals.
• SWE shows promise as a valuable tool for forensic applications in time-of-death estimation.