Artifacts in postmortem CT-imaging of the brain: A cooling effect?

Abstract

We would like to present two cases of middle-aged men found dead outdoors, in relatively low temperatures, whose postmortem brain CT scan exhibited unusual findings. Both cases presented traumatic injuries, mainly cerebral (bleeds, contusions). The first case involved a 55-year-old man, found dead in front of his house, mostly covered by snow, with an ambient temperature reaching − 1.8 °C. Before the autopsy, a native (without contrast) postmortem CT scan was performed which revealed a linear delimitation between the anterior and posterior regions of the brain, along with hypodensity in the anterior region, compatible with an advanced state of decomposition. The second case involved a 77-year-old man, found dead on the bottom of a cliff where his car was found. Temperatures recorded then approached 9 °C. However, a technical glitch in the cooling cell during the storage of the corpse was reported. The subsequent postmortem CT scan performed before the autopsy showed a grossly circular zone of hypodensity across the periphery of the brain with a centro-peripheral and right-left gradient. Furthermore, macroscopic and microscopic examinations of the brain didn’t reveal any pathological findings concerning the density differences observed on imaging in both cases. These two cases seem to highlight the processes through which the cold might affect brain tissue and his appearance on imaging, which could consequently represent a potential pitfall in postmortem forensic investigations. We intend to encourage further studies on this topic, to allow correct interpretation of such CT scan findings in forensic cases, and to open the debate about the possible causes of this phenomenon.

Keywords

• Postmortem computed tomography
• PMCT
• Brain CT
• Freezing
• Cold
• Postmortem magnetic resonance