BACKGROUND: In forensic medicine, documentation of findings is essential. During an autopsy, this is usually achieved by photography. However, there are numerous injuries that remain undetected even during a classic autopsy. In recent years, the importance of forensic radiology has grown in many countries to improve the documentation of findings and to increase the quality of post-mortem examinations.
METHODS: While many methods, such as conventional X‑rays or computed tomography, can be transferred quite easily to the post-mortem field, there are other methods that are more difficult to adapt. For example, performing a post-mortem angiography requires a specific concept that allows the vascular system to be filled and a contrast agent to circulate. Performing post-mortem magnetic resonance imaging is also a challenge, as image contrast depends on the temperature of the body being examined. When applying forensic radiology on living persons in the field of \"clinical forensic medicine\", there are further elements to consider. In particular, the question arises if radiological methods are acceptable for purely forensic medical purposes without a clinical indication.
CONCLUSIONS: This overview article is intended to explain the various methods of forensic radiology, their areas of application, and their advantages and disadvantages. It also describes important historical developments in the use of forensic radiology and its current spread in German-speaking countries as well as current and future developments. Thanks to this information and a summarizing overview table, clear indications and recommendations for the use of forensic radiology in practice can be obtained.
UNASSIGNED: HINTERGRUND: In der Rechtsmedizin ist die Dokumentation von Befunden essenziell. Während einer Obduktion erfolgt dies zumeist durch die Fotografie. Jedoch gibt es zahlreiche Verletzungen, die auch bei einer klassischen Obduktion unentdeckt bleiben. In den letzten Jahren wuchs in zahlreichen Ländern zur Verbesserung der Befunddokumentation und zur Steigerung der Qualität der postmortalen Untersuchung der Stellenwert der forensischen Radiologie.
METHODS: Während viele Methoden, wie die konventionelle Röntgenbildgebung oder die Computertomographie (CT) relativ einfach in den postmortalen Bereich übernommen werden können, gibt es andere Methoden, die sich schwieriger anpassen lassen. So benötigt z. B. die Durchführung einer postmortalen Angiographie ein spezifisches Konzept, welches das Auffüllen des Blutgefäßsystems und das Zirkulieren eines Kontrastmittels erlaubt. Auch die Durchführung einer postmortalen Magnetresonanztomographie (MRT) ist eine Herausforderung, da der Bildkontrast stark von der Temperatur des zu untersuchenden Körpers abhängt. Beim Einsatz an lebenden Personen, im Bereich der „klinischen Rechtsmedizin“, gibt es weitere Elemente zu beachten. So stellt sich insbesondere die Frage, welche radiologischen Methoden ohne klinische Indikation für rein rechtsmedizinische Fragestellungen zulässig sind.
UNASSIGNED: Dieser Übersichtsartikel soll die verschiedenen Methoden der forensischen Radiologie, ihre Einsatzbereiche sowie ihre Vor- und Nachteile erläutern. Außerdem werden wichtige historische Entwicklungen zum Einsatz der forensischen Radiologie und zu ihrer aktuellen Verbreitung im deutschsprachigen Raum sowie zu aktuellen und zukünftigen Entwicklungen beschrieben. Dank dieser Informationen und einer zusammenfassenden Übersichtstabelle können klare Hinweise und Empfehlungen zum Einsatz der forensischen Radiologie in der Praxis erhalten werden.

Post-mortem (PM) imaging has potential for identifying individuals by comparing ante-mortem (AM) and PM images. Radiographic images of bones contain significant information for personal identification. However, PM images are affected by soft tissue decomposition; therefore, it is desirable to extract only images of bones that change little over time. This study evaluated the effectiveness of U-Net for bone image extraction from two-dimensional (2D) X-ray images. Two types of pseudo 2D X-ray images were created from the PM computed tomography (CT) volumetric data using ray-summation processing for training U-Net. One was a projection of all body tissues, and the other was a projection of only bones. The performance of the U-Net for bone extraction was evaluated using Intersection over Union, Dice coefficient, and the area under the receiver operating characteristic curve. Additionally, AM chest radiographs were used to evaluate its performance with real 2D images. Our results indicated that bones could be extracted visually and accurately from both AM and PM images using U-Net. The extracted bone images could provide useful information for personal identification in forensic pathology.

Forensic practitioners need contemporary anthropological data for the identification of human remains. The clavicle possesses a high degree of variability in its anatomical, biomechanical, and morphological features that are sex-dependent albeit population specific. The aim of this study was to develop sex estimation models for Malaysian individuals using post-mortem computed tomographic images of the clavicle. Sample comprised scans of 2.0 mm resolution of 405 individuals (209 male; 196 female) aged between 19 to 88 years. These scans were reconstructed and visualized using Infinitt. Six clavicular measurements (i.e. maximum length, C1; midshaft circumference, C2; midshaft maximum diameter, C3; midshaft minimum diameter, C4; maximum breadth of the sternal end, C5; and maximum breadth of the acromial articular surface, C6) were obtained from these images. Data were analyzed using descriptive statistics and discriminant function analysis. Measurements taken from the images were highly precise (ICC = 0.770-0.999). There is a significant difference between all parameters and sex (p < 0.001), however none for age and ethnic group. A multivariate sex estimation model was developed: Sex = (C1*0.86) + (C2*0.236) + (C3*-0.145) + (C5*- 0.074) - 17.618; with an accuracy rate of 89.1 % and sex bias of -3.2 %. Lower accuracy rates were obtained for single variable models (61.5-83.2 %). The resultant sex discriminant models can be used for estimating sex based on the clavicle in our local forensic practice.

Epicardial adipose tissue (EAT) deposition has been long associated with heart weight. However, recent research has failed to replicate this association. We aimed to determine the association of EAT volume with heart weight in post-mortem cases and identify potential confounding variables. EAT volume derived from post-mortem computed tomography (PMCT) and heart weight were measured in post-mortem cases (N = 87, age: 56 ± 16 years, 28% female). Cases with hypertrophied heart weights (N = 44) were determined from reference tables. Univariable associations were tested using Spearman correlation and simple linear regression. Independence was determined with stepwise regression. In the total cohort, EAT volume (median 66 ± 45 cm3) was positively associated with heart weight (median 435 ± 132 g) at the univariable level (r = 0.6, P < 0.0001) and after adjustment for age, female sex, and various body size metrics (R2 adjusted = 0.41-0.57). Median EAT volume was 1.9-fold greater in cases with hypertrophic hearts (P < 0.0001) but with considerably greater variability, especially in cases with extreme EAT volume or heart weight. As such, EAT volume was not associated with heart weight in hypertrophic cases, while a robust independent association was found in non-hypertrophic cases (R2 adjusted = 0.62-0.86). EAT mass estimated from EAT volume found that EAT comprised approximately 13% of overall heart mass in the total cases. This was significantly greater in cases with hypertrophy (median 15.5%; range, 3.6-36.6%) relative to non-hypertrophied cases (12.5%, 3.3-24.3%) (P = 0.04). EAT volume is independently and positively associated with heart weight in post-mortem cases. Excessive heart weight significantly confounded this association.

Spinal deformities, including kyphoscoliosis, have been consistently documented in cetaceans. However, the majority of reported cases of kyphoscoliosis in cetaceans pertain to bottlenose dolphins, with limited information on its occurrence in narrow-ridged finless porpoise (NFP) (Neophocaena asiaeorientalis).
In November 2021, two deceased NFPs were discovered stranded on the shores of the Republic of Korea. As part of the pioneer stranded cetacean imaging programme in the Republic of Korea, both carcasses underwent post-mortem computed tomography (PMCT), revealing congenital and degenerative traumatic kyphoscoliosis, respectively.
Although kyphoscoliosis may not have directly caused the demise of these individuals, it is hypothesized that the reduced spinal range of motion and mobility associated with kyphoscoliosis may have contributed to their deaths.
This case report presents the first documented cases of kyphoscoliosis in two NFPs stranded in Korean waters, utilizing PMCT as an efficient methodology for assessing skeletal abnormalities in cetaceans.

Pericardial effusion can be a sign of significant underlying diease and, in some cases, may lead to death. Post-mortem computed tomography (PMCT) is a well-established tool to assist death investigation processes in the forensic setting. In practice, the scarcity of well-trained radiologists is a challenge in processing raw whole-body PMCT images for pericardial effusion detection. In this work, we propose a Pericardial Effusion Automatic Detection (PEAD) framework to automatically process raw whole-body PMCT images to filter out the irrelevant images with heart organ absent and focus on pericardial effusion detection. In PEAD, the standard convolutional neural network architectures of VGG and ResNet are carefully modified to fit the specific characteristics of PMCT images. The experimental results prove the effectiveness of the proposed framework and modified models. The modified VGG and ResNet models achieved superior detection accuracy than the standard architecture with reduced processing speed.

The present case report aims to outline the post-mortem findings of an East Asian finless porpoise with upper aerodigestive tract obstruction using different post-mortem computed tomography (PMCT) visualization techniques and discusses the potential cause of death of this individual. A dead-stranded adult male East Asian finless porpoise was recovered from the Northern coast of Jeju Island, Republic of Korea. The carcass was frozen in Jeju National University within 2 h upon first reported. The PMCT examinations were performed at 120 kVp, 200 mAs with a section thickness of 1 mm. The scan field of view (sFOV) was set to 400 mm. Four image rendering techniques, including multi-planar reconstruction, three-dimensional volume rendering, perspective volume rendering, and minimum intensity projection technique, were used to aid the diagnosis of upper aerodigestive tract obstruction in the stranded finless porpoise. Conventional necropsy was performed to provide a complete necropsy report. Using PMCT, a Sebastidae of 24 cm measured length was found to be lodged in the left pharyngeal food channel and esophagus of the finless porpoise. Hard rays of the pectoral fin of the lodged fish have impaled the esophageal mucosa. Fishing gear was found to embed at the dorsal side of the lodged fish. The trachea was compressed ventrally and the arytenoepiglottic tube opening has been narrowed, which may precipitate to the finless porpoise difficult breathing. Pulmonary hyperinflation, pulmonary edema, pneumothorax, pneumopericardium, and pneumorrhachis were observed. This case report represents the first documentation of potential radiological indicators of upper aerodigestive tract obstruction in the East Asian finless porpoise using PMCT. Spatial location of the lodged item could be rendered in situ as the time of death. It has demonstrated that PMCT could provide objective measurements to adjunct the necropsy findings in diagnosis of fatal aerodigestive tract obstruction in stranded cetaceans.

Forensic pathologists may use 3D prints as demonstrative aids when providing expert testimony in court of law, but the effects remain unclear despite many assumed benefits. In this qualitative study, the effects of using a 3D print, demonstrating a blunt force skull fracture, in court were explored by thematic analysis of interviews with judges, prosecutors, defence counsels, and forensic pathologists with the aim of improving the expert testimony. Five semi-structured focus groups and eight one-to-one interviews with a total of 29 stakeholders were transcribed ad verbatim and analysed using thematic analysis. The study found that a highly accurate 3D print of a skull demonstrated autopsy findings in detail and provided a quick overview, but sense of touch was of little benefit as the 3D print had different material characteristics than the human skull. Virtual 3D models were expected to provide all the benefits of 3D prints, be less emotionally confronting, and be logistically feasible. Both 3D prints and virtual 3D models were expected to be less emotionally confronting than autopsy photos. Regardless of fidelity, an expert witness was necessary to translate technical language and explain autopsy findings, and low-fidelity models may be equally suited as demonstrative aids. The court infrequently challenged the expert witnesses\' conclusions and, therefore, rarely had a need for viewing autopsy findings in detail, therefore rarely needing a 3D print.

OBJECTIVE: In cases of drowning, the presence of sphenoid sinus fluid is a non-specific autopsy finding. However, studies have reported that fluid accumulation in the paranasal sinuses is more commonly observed in drowning victims. Furthermore, some laboratory tests, such as diatom and electrolyte analysis, can serve as supplementary diagnostic tools for diagnosing drowning. Therefore, accurate sphenoid sinus fluid sampling is an important aspect of an autopsy in suspected drowning cases. The aim of this study was to identify the significance of evaluating sphenoid sinus fluid by PMCT images in cases of drowning.
METHODS: We retrospectively reviewed 54 drowning victims who underwent PMCT and forensic autopsy. Fluid volume in the sphenoid sinus was measured using a graduated syringe during autopsy and a three-dimensional (3D) workstation based on PMCT images was used for the purpose of comparison. The Mann-Whitney U test and Spearman\'s rank correlation coefficient was used to evaluate statistically significant differences and correlations. Additionally, a Bland-Altman plot was employed to assess the agreement between PMCT and autopsy.
RESULTS: The median volume was 1.65 (range 0.00-12.4) ml and 1.55 (range 0.00-7.00) ml in the PMCT and autopsy, respectively, showing a statistically insignificant difference (p = 0.294) and a significant correlation (Rs = 0.896). In 35 cases, the PMCT overestimated the fluid volume more than the autopsy, whereas in 14 cases, the PMCT underestimated the fluid volume. No fluid was identified in seven cases during the autopsy, whereas in five patients, no fluid was found in both PMCT and autopsy. By analyzing the Bland-Altman plot, a bias of 0.73 ± 1.4 ml and limits of agreement ranging from -2.04 to 3.51 ml were observed for sphenoid sinus fluid volume measurements.
CONCLUSIONS: Based on the limitations of traditional fluid volume measurement in the sphenoid sinus during autopsy, we propose the utilization of PMCT volumetric analysis prior to autopsy as a means to enhance the detection of sphenoid sinus fluid in cases of drowning.

In forensic medicine, fatal hypothermia diagnosis is not always easy because findings are not specific, especially if traumatized. Post-mortem computed tomography (PMCT) is a useful adjunct to the cause-of-death diagnosis and some qualitative image character analysis, such as diffuse hyperaeration with decreased vascularity or pulmonary emphysema, have also been utilized for fatal hypothermia. However, it is challenging for inexperienced forensic pathologists to recognize the subtle differences of fatal hypothermia in PMCT images. In this study, we developed a deep learning-based diagnosis system for fatal hypothermia and explored the possibility of being an alternative diagnostic for forensic pathologists. An in-house dataset of forensic autopsy proven samples was used for the development and performance evaluation of the deep learning system. We used the area under the receiver operating characteristic curve (AUC) of the system for evaluation, and a human-expert comparable AUC value of 0.905, sensitivity of 0.948, and specificity of 0.741 were achieved. The experimental results clearly demonstrated the usefulness and feasibility of the deep learning system for fatal hypothermia diagnosis.