International Journal of Legal Medicine最新文献

The time elapsed after death is known as the postmortem interval (PMI). After death, the body undergoes changes such as algor mortis, rigor mortis, livor mortis, and putrefaction. In forensic medicine, PMI is traditionally determined using standard methods and forensic entomology, both of which can be affected by environmental conditions. Recently, genetic materials, which are less influenced by the environment, have gained attention in PMI studies. Cell-free DNA (cfDNA) comprises short DNA fragments released into the bloodstream due to cell necrosis and apoptosis. This study quantitatively analyzed cfDNA and specific microRNAs (miRNAs) - miR-122, miR-133, miR-1, miR-16, and let-7e - in serum samples from rats at various time intervals to assess their correlation with PMI. The results were analyzed using Ct, ΔCt, ΔΔCt, and fold change methods. Statistically, miR-16 and miR-122 had lower ΔCt values at all time points. miR-16 showed a lower ΔΔCt average at 24 and 48 h and the highest fold change at 24 h. Reference genes GAPDH and ACTB declined over time, with higher averages at 0, 6, and 12 h compared to 24 and 48 h. This research is the first to quantitatively explore cfDNA's potential role in PMI estimation.

This study conducted a retrospective analysis of head and neck magnetic resonance imaging (MRI) scans from the Pediatric Radiology Department at Ankara University Faculty of Medicine, covering the period from 2014 to 2022. The objective was to assess facial soft tissue thickness (FSTT) in children aged 3-18 years, thereby contributing to forensic and anthropological identification processes and establishing a dataset. A sample of 300 healthy youngsters was included, divided into three age groups: 3-8 years, 9-13 years, and 14-18 years, according to age and body mass index (BMI) percentiles. The findings demonstrate that FSTT rises with age, with subnasale dimensions attaining 15.0 ± 2.9 mm in males and 12.6 ± 2.3 mm in females at the age range of 14-18 years (p < 0.001). Males demonstrated elevated FSTT values at the glabella landmark, whereas children in the 85th and 95th BMI percentiles exhibited significantly higher FSTT values (p < 0.001). The most significant BMI-related differences were observed in the labiale superius and subnasale in females aged 9 to 18 years. This study offers the pilot comprehensive dataset on variations in FSTT across children, categorized by age, sex, and BMI in Türkiye. The dataset primarily facilitates profile-based approximations, given its emphasis on midline features. However it may also provide limited utility in 3D facial reconstruction efforts. The findings will be essential for forensic and anthropological research. The findings address a gap in the forensic science literature and highlight the necessity for more research with varied age groups and foreigners.

The likelihood ratio (LR) is a recommended metric for assessing the strength of genetic information in relationship testing, one of the most important tasks in forensic science. LR calculation incorporate population frequencies, which is affected by population substructure. This study utilized population frequency data from 18 short tandem repeat (STR) loci across 13 Chinese populations, encompassing both majority and minority ethnic groups. Six kinship types were constructed for each population. To understand the impact of population substructure on kinship testing, LRs were calculated using various frequency data: population-specific allele frequencies, national allele frequencies, and national allele frequencies adjusted with overall national F_ST or population-specific F_ST. LRs were also compared using the cutoff and comparison methods. The study found that LRs calculated using national allele frequencies tend to be the largest, which could overestimate the degree of relatedness compared to population-specific allele frequencies. Fst correction decreased the LR values, resulting in more conservative outcomes and suggested more distant relationships. While the F_ST correction had a minimal effect on the majority and some minority populations across different kinships, it was insufficiently conservative for more isolated minority populations when the overall national F_ST was applied. In conclusion, for isolated subpopulations with F_ST values above the national average, utilizing population-specific allele frequencies and applying higher F_ST values (e.g. 0.03 or 0.05) leads to more accurate and conservative inferences of relatedness. In contrast, for other groups, national frequencies without F_ST correction appear sufficient for relationship testing.

In the past 10 years, the Multi-phase Post-mortem Computed Tomography Angiography (MPMCTA) has considerably improved the quality and precision of postmortem diagnoses, particularly in cases with vascular implication. MPMCTA is known to have higher sensitivity for detecting the source of a hemorrhage than autopsy. Death by upper gastro-intestinal (GI) bleeding is not so uncommon in forensic practice. MPMCTA, like any other diagnostic test, can produce artifacts that must be recognized. Radiologists at our center have previously encountered images suggestive of upper GI bleeding that were ultimately identified as artifacts during autopsy. This is why we believe it is essential to establish criteria to differentiate true bleeding from artifacts. The aim of our study was to compare the diagnostic value of MPMCTA and autopsy in detecting and localizing sources of upper GI bleeding, and to establish diagnostic criteria to aid in the interpretation of upper GI contrast extravasation on angiography. We conducted a retrospective cross-sectional study, analyzing MPMCTA and autopsy data from 326 human bodies. In the GI tract, contrast extravasation should not be immediately interpreted as a sign of active bleeding. In cases of true GI hemorrhage, MPMCTA reveals specific features suggestive of bleeding, such as hyperdense material within the GI tract on native CT, and a focal contrast leakage during the arterial or venous phase. This article offers tips that may help radiologists and forensic pathologists distinguish true bleeding from artifacts when interpreting MPMCTA findings in the upper GI tract.

Background: Recently, post-mortem photon-counting CT (PMPCCT) has been introduced to forensic imaging. Compared to conventional energy integrating post-mortem CT (PMCT), PMPCCT enables ultra-high resolution (UHR) imaging, which is particularly suitable for visualizing fine fractures and fissures. These are often found in rib trauma, which is usually relevant in forensic medicine. The aim of this study was to evaluate the diagnostic accuracy of rib fracture detection using PMPCCT compared to PMCT and forensic autopsy.

Methods: A total of n = 20 bodies that had suffered blunt chest trauma before death and n = 5 non-trauma control cases were investigated. PMCT and PMPCCT were conducted prior to forensic autopsy. Two observers (radiologist and forensic pathologist) analyzed PMCT images (reconstructed with a slice thickness of 0.5 mm in a 512 matrix) and PMPCCT images (reconstructed with slice thicknesses of 0.5 mm and 0.2 mm (UHR) in a 1024 matrix). Imaging diagnosis of rib fractures was compared to autopsy diagnosis as gold standard. The diagnosis of different types of rib fractures assessed at imaging was compared between PMCT and PMPCCT.

Results: Inter-rater agreement between the two observers was good (κ = 0.79). Both PMCT and PMPCCT diagnosed less rib fractures than the autopsy (n = 356 fractures). Compared to PMCT, UHR-PMPCCT demonstrated slightly higher sensitivity (e.g., 92% vs. 82% in observer 1), slightly higher specificity (e.g., 97% vs. 95%), and lower positive predictive value (e.g., 75% vs. 82%) for the diagnosis of all rib fractures. Chi-squared tests showed significant differences (p-value < 0.05 in both observers) between UHR-PMPCCT and PMCT for the diagnosis of incomplete rib fractures with visible dehiscence of one cortical line.

Conclusion: Based on the results, it is questionable whether PMPCCT offers additional forensic value over PMCT for the specific forensic issue of diagnosing rib fractures.

Sudden Arrhythmic Death Syndrome (SADS), Sudden Unexpected Death In Epilepsy (SUDEP) and Sudden Infant Death Syndrome (SIDS) present some overlaps and similarities in terms of molecular autopsy and pathophysiological mechanism. Genes associated with cardiac arrhythmias represent promising biomarkers, in light of the growing evidence of neurocardiac interconnections and phenotypic similarities between SUDEP, SADS and also SIDS. The interactions between these different forms of sudden death are reciprocal and could help to understand the mechanism of death that in some cases remains unexplained. In this review of the literature we analyse the overlaps and the common aspects between these different conditions of sudden death, we discuss the clinical, social and medico-legal implications. SIDS, SADS and SUDEP still represent a huge challenge for the Forensic Pathologist and their diagnostic interpretation contains some ambiguities and evaluation difficulties. All cases of sudden death require a thorough cardio-pathological and neuropathological evaluation. A thorough anamnesis and molecular analysis of the major channel protein genes (such as SCN5A, RYR2, KCHN2, and KCNQ1) should be performed in these cases, in addition to histological and toxicological analyses. Only a thorough and multidisciplinary evaluation can help to better define the cases of sudden death, avoid improper classifications and clarify the pathological mechanism more precisely.

Background: The use of artificially intelligent Language Models (LLMs) like ChatGPT is increasing rapidly in medicine, but their accuracy, reasoning quality, and contextual safety remains an issue. This is especially relevant for forensic pathology, where balanced reasoning, contextual sensitivity, and precise communication are essential. We performed an in-depth assessment of ChatGPT's capabilities and limitations for forensic pathology, which also improves our understanding of the risks and benefits of LLM use in medicine more broadly.

Methods: ChatGPT-4.5 Turbo's performance was tested using a multifaceted mock exam, consisting of core elements of the forensic pathology fellowship exam of the Royal College of Pathologists of Australasia (RCPA). The mock exam included essay-style questions, image-based tasks, and case reporting. ChatGPT's responses were blindly marked by experienced examiners according to standard RCPA criteria, assessing factual accuracy, reasoning structure, and communication quality.

Results: ChatGPT performed well on most essay-style knowledge questions, achieving higher scores on topics with well-established knowledge. Performance was however poor for tasks requiring complex reasoning, image interpretation, or the context-dependent analysis of autopsy findings. Importantly, ChatGPT's output was always phrased fluently and persuasively, creating an impression of confidence that was independent of factual accuracy.

Conclusions: ChatGPT can reliably reproduce well-established forensic pathology knowledge. However, it lacks the capabilities needed for higher-level tasks and often generates unjustifiably confident and misleading output. Its use may be acceptable for low-risk administrative or educational purposes, provided output is carefully reviewed by qualified experts. Non-specialists should not rely on such tools for forensic pathology information. Continued evaluation is needed to ensure safe and responsible use.

Post-mortem imaging has become an important adjunct or alternative to autopsy in perinatal pathology and forensic medicine, particularly when conventional autopsy is limited or declined. However, high-field MRI, currently the post-mortem imaging gold standard for fetuses, is not always available in many forensic settings. The aim of this study was to evaluate whether a 0.31 Tesla low-field MRI scanner, which offers advantages in affordability, installation, infrastructural requirements such as reduced power, cooling, and shielding demands, and lower safety constraints associated with its field strength, can deliver diagnostically relevant information in post-mortem fetal examinations within a forensic context. Three fetuses underwent post-mortem low-field MRI prior to autopsy and histopathological assessment. Imaging findings were compared with autopsy results to evaluate diagnostic concordance and potential added value in a forensic context. Low-field MRI successfully identified key anatomical abnormalities: Fetus #1 showed a cerebral lesion on MRI that could not be recognized during the autopsy due to autolysis-related loss of structural integrity of the brain after opening the skullcap. Fetus #2 presented with a left-sided diaphragmatic hernia with enterothorax. Fetus #3 exhibited gastroschisis and a renal abnormality. Using the 0.31 Tesla low-field MRI scanner provided sufficient diagnostic detail to support and complement the forensic examinations of fetal deaths. It can improve the documentation and interpretation of findings in perinatal forensic cases, enhance diagnostic certainty in decomposed or fragile remains, and offer a viable alternative when parental refusal or legal constraints prevent full autopsy.

Postmortem interval (PMI) estimation is a critical component of forensic investigations as it can help establish a timeline of events and assist in reducing a pool of missing persons or potential suspects. Despite its importance, the accuracy of PMI estimation remains challenging due to the complexity of decomposition and limitations of current methods, particularly in the later postmortem period. Proteomics has shown potential as a more objective method, with current studies taking an untargeted approach to identify informative peptide targets. Previous studies in our laboratory analysed human muscle tissue and identified 12 peptide ratios, consisting of 19 individual peptides, that were correlated with decomposition time. This study aimed to optimise the detection of these 19 peptide targets using a targeted liquid chromatography triple quadrupole mass spectrometry (LC-QQQ) method suited for casework applications and instrument platforms commonly found in forensic laboratories. Of the 19 peptide targets, 17 were optimised to be reproducible. Additionally, a longitudinal analysis in authentic human samples was conducted over a 14-day period postmortem to monitor detection throughout the decomposition process. All but one of the targets produced interpretable results, and data analysis was performed to generate peptide ratios. After log2 transformation, two of the previously proposed peptide ratios showed linear trends. Overall, this study has shown that a targeted LC-QQQ method is a viable system for the detection of PMI peptide targets from human postmortem muscle tissue and has demonstrated the potential for this type of analysis to be validated and applied in routine forensic casework.