Use of Postmortem Computed Tomography to Detect Bowel Obstruction and its Relationship to the Cause of Death

Postmortem computed tomography differentiation between intraperitoneal decomposition gas and pneumoperitoneum

PURPOSE

The aim of this study is to investigate the ability of postmortem computed tomography (PMCT) to distinguish intraperitoneal decomposition gas from pneumoperitoneum due to intestinal perforation.

METHODS

This retrospective study investigated the factors affecting intraperitoneal gas in two groups of 14 decedents as detected by postmortem CT performed in the Department of Legal Medicine of Hamburg University. The first group died with a cause of death associated with intestinal perforation, and the second group with other different natural causes of death. These factors include postmortem interval, gas volume, gas distribution, radiology alteration index (RAI), and pneumoperitoneum-associated pathology.

RESULTS

The findings of this study showed the appearance of specific gas distribution patterns and a significant increase in gas volumes in the cases of intestinal perforation. Moreover, postmortem interval and the pneumoperitoneum-associated pathology could help distinguish postmortem-generated gas from pneumoperitoneum.

CONCLUSION

Based on the findings of this study, we propose that these findings can improve the proper detection of intestinal perforation cases in the future.

Relevant findings on postmortem CT and postmortem MRI in hanging, ligature strangulation and manual strangulation and their additional value compared to autopsy - a systematic review

Several articles have described the use of postmortem computed tomography (CT) and postmortem magnetic resonance imaging (MRI) in forensic medicine. Although access to CT scanners and, particularly, access to MRI scanners, is still limited for several institutes, both modalities are being applied with increasing frequency in the forensic setting. Certainly, postmortem imaging can provide crucial information prior to autopsy, and this method has even been considered a replacement to autopsy in selected cases by some forensic institutes. However, the role of postmortem imaging has to be assessed individually according to various injury categories and causes of death. Therefore, this systematic review focuses on the role of postmortem CT and MRI in cases of hanging and ligature and manual strangulation. We assessed the most common and relevant findings on CT and MRI in cases of strangulation and compared the detectability of these findings among CT, MRI and autopsy. According to the available literature, mainly fractures of the hyoid bone or thyroid cartilage were investigated using postmortem CT. Compared to autopsy, CT demonstrated equivalent results concerning the detection of these fractures. A currently described "gas bubble sign" may even facilitate the detection of laryngeal fractures on CT. Regarding the detection of hemorrhages in the soft tissue of the neck, postmortem MRI is more suitable for the detection of this "vital sign" in strangulation. Compared to autopsy, postmortem MRI is almost equally accurate for the detection of hemorrhages in the neck. Another "vital sign", gas within the soft tissue in hanging, which is hardly detectable by conventional autopsy, can be clearly depicted by CT and MRI. The number of cases of manual and ligature strangulation that were investigated by means of postmortem CT and MRI is much smaller than the number of cases of hanging that were investigated by CT and MRI. Likewise, judicial hanging and the hangman's fracture on postmortem imaging were described in only a few cases. Based on the results of this systematic review, we discuss the additional value of CT and MRI in fatal strangulation compared to autopsy, and we reflect on where the literature is currently lacking.

Intestinal obstruction as a cause of death in the mentally disabled

Two cases of intestinal obstruction in the mentally disabled are reported. The first case concerns 61-year-old oligophrenic woman who resided in a nursing home, where she was found hypotensive and unresponsive. Upon opening the peritoneal cavity at autopsy, extremely dilated (measuring on average 12 cm in diameter) loops of the colon emerged- they compressed the small intestine and other intraperitoneal organs, lifting both hemidiaphragms deep into the pleural cavity. Lodged firmly into the rectum, a partly disintegrated sanitary pad was found. In the second case, young man with Down syndrome was found dead in his room in a nursing facility. At autopsy, a massively dilated stomach and intestinal loops emerged, interposing one of the loops between the liver and right hemidiaphragm (pushing it to the 3rd intercostal space). This was caused by a volvulus - the cecum, the entire ascending colon and hepatic flexure were gangrenous, dilated (the maximum diameter was 15 cm) and twisted in a full circle around the mesenteric attachment. There were no signs of colon perforation. In both cases, intellectual disability was at the core of poor communication and delayed medical treatment, which led to a fatal outcome. Caregivers must be trained to recognize distress in the mentally disabled, especially since the symptoms and signs of gastrointestinal diseases may be subtle, or at least less recognizable. By performing careful physical examination medical staff should search more cautiously for these signs. Any suspicion of mistreatment or neglect of the mentally impaired requires a medico-legal investigation and autopsy.