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.

Post mortem computed tomography (PMCT) can be used as a triage tool to better identify cases with a possibly non-natural cause of death, especially when high caseloads make it impossible to perform autopsies on all cases. Substantial data can be generated by modern medical scanners, especially in a forensic setting where the entire body is documented at high resolution. A solution for the resulting issues could be the use of deep learning techniques for automatic analysis of radiological images. In this article, we wanted to test the feasibility of such methods for forensic imaging by hypothesizing that deep learning methods can detect and segment a hemopericardium in PMCT. For deep learning image analysis software, we used the ViDi Suite 2.0. We retrospectively selected 28 cases with, and 24 cases without, hemopericardium. Based on these data, we trained two separate deep learning networks. The first one classified images into hemopericardium/not hemopericardium, and the second one segmented the blood content. We randomly selected 50% of the data for training and 50% for validation. This process was repeated 20 times. The best performing classification network classified all cases of hemopericardium from the validation images correctly with only a few false positives. The best performing segmentation network would tend to underestimate the amount of blood in the pericardium, which is the case for most networks. This is the first study that shows that deep learning has potential for automated image analysis of radiological images in forensic medicine.

Objective The aims of this study were (1) to provide an overview of craniocervical magnetic resonance imaging (MR) findings following nonfatal strangulation (NFS), (2) to detect the time dependency of the presence of these findings, and (3) to explore the additional value of MR with regard to the forensic interpretation of NFS. Methodology All 633 victims of manual strangulation between October 2011 and March 2018 were examined, including the case history and external findings. Following written consent, 114 cases were included in the study. The duration between the event, clinical forensic examination, and MR was noted. Radiologic images were reviewed by a clinical and a forensic radiologist. ResultsThe case group consisted of 90 women and 24 men with a mean age of 32.5 years. Delimitable external findings were present in 93% (N = 106) of cases. MR yielded a positive finding in 43% of cases (N = 49). There was no significant difference in the mean time interval between examinations between MR-positive and MR-negative cases. Perilaryngeal fluid accumulation was associated with difficulty swallowing and victims put in a chokehold. All cerebral MR were unremarkable, except for one patient with edema of the corpus callosum. Conclusions The role of craniocervical MR following NFS is currently limited, particularly with regard to the forensic interpretation of NFS. MR may reveal internal injury in victims who report subjective symptoms of airway compression and in those who were placed in a chokehold. The presence of MR findings is not dependent on immediate examinations following the assault. Key Points• Magnetic resonance imaging does not currently provide additional value for the estimation of the severity of nonfatal manual strangulation.• Magnetic resonance imaging of the neck may reveal internal injury in cases without external findings, particularly in victims placed in a chokehold and with symptoms of airway compression. • The incidence of carotid artery dissections and laryngeal fractures is low in victims of nonfatal manual strangulation.

Pneumopericardium (PPC) describes the collection of gas in the pericardial sac. In tension Pneumopericardium (tPPC), this collection of gas may lead to cardiac tamponade. PPC following blunt trauma is considered a rare finding, as reflected by the low number of case reports on the topic. We analyzed the prevalence and pathophysiology of PPC and the associated trauma in 44 cases of falls from height. We retrospectively analyzed postmortem CT data and autopsy reports of fatal falls in the period March 2014-2017. A valid estimation of the height of the fall and a documented impact on an even and hard surface were inclusion criteria. A total of 44 cases were included in the study. We identified PPC in 18 of the 44 cases, and it was associated with an increased height of the fall, alongside aortic, pericardial, and myocardial ruptures. All cases with PPC also presented with bilateral pneumothorax. Five cases presented with a "ballooning" pericardium, indicating tPPC. PPC is a common finding in cases of falls from great heights. Due to a significant correlation with height and thus impact severity, PPC may be used as a reconstructive element in medico-legal investigations. Association with trauma makes PPC a sign of severe thoracic injury in postmortem and clinical radiology.

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