Assessment of eyeball findings on two sequential post-mortem computed tomography (PMCT) : no reliable marker for post-mortem interval

BACKGROUND: It is important to understand post-mortem changes in post-mortem computed tomography (PMCT) image interpretation. Only a few studies have focused on the eyeballs. This study aimed to clarify the changes in eyeball findings on PMCT and examine whether it is possible to estimate the post-mortem interval (PMI) based on this findings. METHODS: During a 13-year period, data from 29 consecutive patients who underwent CT scans twice (the first CT taken at the time of death in our hospital: time from confirmation of death from - 4 h 15 min to 2 h 17 min, and the second CT taken prior to autopsy in our forensic facility: from 15 h 27 min to 196 h 32 min) were analyzed after excluding performing first CT scans during the return of spontaneous circulation, under 2 years of age and periorbital damage due to trauma. The maximum longitudinal diameter, lens position, and vitreous radiodensities were measured. The Wilcoxon signed-rank test was used for statistical analysis. The correlation between the changes in each measurement value and the elapsed time of the two scans was examined using regression analysis. RESULTS: In the second scan, the maximum longitudinal diameter was significantly reduced (p < 0.0001), and the vitreous radiodensities significantly increased (p < 0.0001). There was no significant change in the distance from the cornea to the lens. However, no correlation was found between any of the findings and the elapsed time. CONCLUSION: With early post-mortem changes, the maximum longitudinal diameter decreased, whereas the vitreous radiodensities increased. It was nevertheless not possible to estimate PMI based on these findings.