Relation between intravascular and intraorgan gas volume and quantity via postmortem CT and putrefaction

Area of Science:

• Forensic pathology
• Radiology
• Medical imaging

Background:

• Assessing postmortem changes is crucial in forensic investigations.
• Postmortem computed tomography (PMCT) offers detailed visualization of internal structures.
• The presence and quantity of gas can be an indicator of postmortem processes.

Purpose of the Study:

• To evaluate the relationship between intravascular and intraorgan gas volume and putrefaction.
• To quantify gas accumulation in various organs and vessels during different stages of decomposition.
• To establish the utility of PMCT in assessing postmortem gas changes.

Main Methods:

• Medico-legal autopsy and PMCT data from 1,156 cases (Jan 2018-Dec 2020) were analyzed.
• Cases with specific exclusions (injury, air embolism, resuscitation) were initially removed, with some reincluded for organ-specific gas assessment.
• Putrefaction was staged (S1-S3), and intravascular/intraorgan gas was graded (G0-G3) using defined criteria.

Main Results:

• A significant increase in intravascular and intraorgan gas was observed with progressing putrefaction (p < 0.01).
• Grade 1 (G1) intravascular gas in the right heart appeared in ~20% of cases from Stage 1 (S1), with no G2 or G3 gas.
• Gas was present in the liver from S1 (~22% of cases), and Grade 3 (G3) gas significantly increased in S3.

Conclusions:

• PMCT demonstrates a clear correlation between the progression of putrefaction and the accumulation of intravascular and intraorgan gas.
• Early putrefaction stages (S1) are characterized by minimal to no significant intravascular gas (G2/G3) or intraorgan gas.
• The findings support the use of PMCT for evaluating decomposition-related gas changes in forensic contexts.