CT analysis of skull contents in naturally mummified human corpses, a multicentric study

This study aimed to assess skull contents, brain appearance, and density on postmortem computed tomography in naturally mummified corpses.

For this purpose, a retrospective multicentric study, including mummified corpses from two French centers (Brest and Nantes) and from the New Mexico Decedent Image Database (USA), was performed by analyzing postmortem computed tomography (PMCT) focused on the head and neck of partially or fully mummified corpses discovered between 2011 and 2022. The PMCT analysis provided data on the CT appearance of brains, allowing them to be classified into four different categories (desiccation, liquefaction, dura mater only (DMO), and absence), and to measure densities (HU) of the brain remains. In addition, data on postmortem intervals (PMI) from Nantes and Brest centers were collected and analyzed to test the link between brain densities and PMIs.

54 cases of naturally mummified corpses were included. The brains were classified as liquefied (56%), desiccated (17 %), DMO (20 %), and absent (7 %) based on their CT appearance. Dehydrated brains were significantly (p < 0.004) denser (median 102 HU, interquartile range (IQR) 41) than either liquefied brains (median 39.5 HU, IQR 9) or brains with DMO (median -25 HU, IQR 57). However, the density of brain remains was not significantly affected by where the bodies were found (p = 0,41). Analysis of PMI and brain densities was performed on 22 cases. The results showed that brain remains were significantly (p = 0.039) denser when they were found after a PMI of more than six months.

Brain desiccation was the aspect with the highest densities on PMCT, and for which we were able to highlight great preservation of anatomical structures observable in living organisms.