Imaging Characteristics of Frozen Corpses: An Analysis Based on Postmortem Computed Tomography

Abstract Background: As traditional autopsy rates decline, the importance of forensic imaging, particularly postmortem computed tomography (PMCT), grows for non-invasive cause of death determination and evidence collection in legal investigations, with unique considerations required for frozen corpses due to the lack of systematic imaging characteristic studies. Aims and Objectives: This study aims to fill the gap in current knowledge by systematically analyzing the PMCT imaging characteristics of frozen corpses. Materials and Methods: This study utilized postmortem computed tomography (PMCT) and postmortem computed tomography angiography (PMCTA) to examine tissue changes during the freezing and thawing process in a total of 61 corpses. Results: The results demonstrated that imaging changes in the brain were most pronounced during freezing and thawing, with a clear correlation to the duration of freezing/thawing and the position of the corpses. Typical ice crystal artifacts were observed in body fluids after freezing, while thawing led to a marked increase and redistribution of internal gas. Serial angiographic studies revealed “pseudo-brain hemorrhage” in the brainstem and cerebellum in several cases due to incomplete thawing and transport. Conclusion: This study provides a comprehensive analysis of the CT imaging characteristics of frozen corpses, elucidating the imaging features during the freezing and thawing processes.