Postmortem changes in the eye on computed tomography images

Background: Ocular tension decreases with increasing postmortem interval (PMI) and eyes collapse with extreme progression of postmortem change; however, time-related changes in postmortem computed tomography (PMCT) findings have not been clarified. This study aimed to quantitatively evaluate the vitreous volume and CT values of the vitreous body to clarify time-related changes in PMCT. Methods: We retrospectively reviewed PMCT images of the eyes of subjects who underwent autopsy at our institution between July 2023 and February 2024. They were classified into four PMI groups: PMI-1: < 1 day, PMI-2: 1-2 days, PMI-3: 3-6 days, PMI-4: >= 7 days. The vitreous volumes and mean CT values of the vitreous chambers were measured. Additionally, the presence of intraocular gas and crystalline lens dislocation was observed. Results: The PMCT images of 131 eyes of 66 patients (41 males, 25 females) were analyzed. The mean age was 63.7 (22-99) years. The volume of the vitreous cavity was significantly decreased at PMI-3 and PMI-4, which indicated scleral depression. Intraocular gas appeared in PMI-4. Lens dislocation began at PMI-3 and was more frequently observed at PMI-4 and in the higher-temperature environment group. Conclusion: Ocular findings on PMCT are useful for estimating the time of death.