Can computed tomography replace or supplement autopsy?

Postmortem computed tomography (PMCT) has been integrated into the practice of many forensic pathologists. To evaluate the utility of PMCT in supplementing and/or supplanting medicolegal autopsy, we conducted a prospective double-blind comparison of abnormal findings reported by the autopsy pathologist with those reported by a radiologist reviewing the PMCT. We reviewed 890 cases: 167 with blunt force injury (BFI), 63 with pediatric trauma (under 5 years), 203 firearm injuries, and 457 drug poisoning deaths. Autopsy and radiology reports were coded using the Abbreviated Injury Scale and abnormal findings and cause of death (COD) were compared for congruence in consensus conferences with novel pathologists and radiologists. Overall sensitivity for recognizing abnormal findings was 71% for PMCT and 74.6% for autopsy. Sensitivities for PMCT/autopsy were 74%/73.1% for BFI, 61.5%/71.4% for pediatric trauma, 84.9%/83.7% for firearm injuries, and 56.5%/66.4% for drug poisoning deaths. COD assigned by reviewing PMCT/autopsy was correct in 88%/95.8% of BFI cases, 99%/99.5% of firearm fatalities, 82.5%/98.5% of pediatric trauma deaths, and 84%/100% of drug poisoning deaths of individuals younger than 50. Both autopsy and PMCT were imperfect in recognizing injuries. However, both methods identified the most important findings and are sufficient to establish COD in cases of BFI, pediatric trauma, firearm injuries and drug poisoning in individuals younger than 50. Ideally, all forensic pathologists would have access to a CT scanner and a consulting radiologist. This would allow a flexible approach that meets the diagnostic needs of each case and best serves decedents' families and other stakeholders.

Assessment of post-mortem submersion interval using total aquatic decomposition scores of drowned human cadavers.

Investigating drowning-related deaths remains a significant problem for forensic personnel all over the world. The previously published decomposition scoring method like the total aquatic decomposition (TAD) score promises to estimate the correct post-mortem submersion interval (PMSI) in aquatic habitats through the assessment and calculation of the decomposition rate and accumulated degree days (ADD). The current study comprised of 53 drowned death cases belonging to various districts of Haryana from May 2016 to August 2017. The regression and Pearson's correlation indicated a significant correlation between the TAD scores and the actual ADD (calculated through water temperatures) (r2  = 0.917) and between the actual and the estimated ADDs (calculated through TAD scores used by Heaton et al. [21]) (r = 0.9585). The results indicated that the estimated ADD tends to over predict the PMSI compared to the actual ADD. It is further confirmed by paired t-test, which showed the mean of actual ADD (mean = 349) to be significantly lower than the mean of estimated ADD (mean = 663). Moreover, these methods will help forensic investigators and researchers formulate region-specific regression equations for PMSI estimation.

Review of the current and potential use of biological and molecular methods for the estimation of the postmortem interval in animals and humans.

We provide here an overview of the state of applied techniques in the estimation of the early period of the postmortem interval (PMI). The biological methods included consist of body cooling, CSF potassium, body cooling combined with CSF potassium, and tissue autolysis. For each method, we present its application in human and veterinary medicine and provide current methodology, strengths, and weaknesses, as well as target areas for improvement. We examine current and future molecular methods as they pertain to DNA and primarily to messenger RNA degradation for the estimation of the PMI, as well as the use of RNA in aging wounds, aging blood stains, and the identification of body fluids. Various types of RNA have different lengths, structures, and functions in cells. These differences in RNAs determine various intrinsic properties, such as their half-lives in cells, and, hence, their decay rate as well as their unique use for specific forensic tests. Future applications and refinements of RNA-based techniques provide opportunities for the use of molecular methods in the estimation of PMI and other general forensic applications.

Forensic necropsies of cattle: a study of Danish cases from 2010 to 2021 and a guideline for forensic examination of cattle.

Forensic post-mortem examinations of animals are carried out on suspicion of violation of European and national legislation. In Denmark, and probably also in other countries with large-scale cattle production, cattle are regularly submitted for forensic assessment. Unfortunately, only few studies of forensic pathology in cattle are available. This paper presents a retrospective study of forensic case files on Danish cattle from January 2010 to December 2021. The case files were characterized with respect to types of lesion, age assessments of lesions and other parameters such as age and sex. A total of 118 forensic case files had been archived and related to 132 cattle (14 weeks-20 years of age; 68% female, 30% male and 2% unknown sex) with 228 lesions. Locomotor disorders constituted the majority of lesions. However, cachexia/emaciation, skin ulcerations and overgrowth of cornual horn were also frequent. Most lesions were chronic (91%) and age assessments for more than 2 weeks were stated for 79% of the lesions. This indicates that in Denmark at least, there is a need to consider how cattle with locomotor disorders are treated in a timely manner in order to avoid prolonged futile treatment and, thereby, suffering. Grossly visible reparative granulation tissue and new bone formation were present in lesions of 1-2 weeks and longer duration. However, all age assessments were stated in broad time intervals due to the lack of scientifically based forensic studies of age assessments of lesions in cattle. Therefore, to improve age assessments in forensic cattle cases, studies concerning the chronology of tissue reparation in cattle are warranted. We also present a guideline for the forensic examination of cattle.

Developing a new scoring method to evaluate human decomposition in a humid, continental (Dfb) climate in Quebec.

The published literature shows a lack of methods to evaluate the patterns and extent of decomposition of human remains and to estimate the post-mortem interval (PMI) in humid, continental (Dfb) climates such as Quebec. The aim of this study was to address this gap in the current knowledge base by providing the first observations from human corpses studied under controlled conditions in Quebec. A 12-month study was conducted at the site for Research in Experimental and Social Thanatology; the first human taphonomy facility in Canada. Six human donors with known time of death were deposited across spring (n = 1), summer (n = 3), and autumn (n = 2) 2021. The lack of suitability of the total body score method to evaluate the extent of decomposition at the facility prompted the development of a new scoring system based on the macromorphoscopic changes observed. The scoring system was applied to the donors to evaluate decomposition throughout seasons. All donors followed comparable decomposition trajectories, regardless of the season of deposition. Eighty-five percent of taphonomic patterns appeared in the first 25 experimental days or 5000 Kelvin accumulated degree days (350 ADD). Extensive desiccation of tissues was observed at a median of 21 experimental days across donors, resulting in a plateau within decomposition with no extensive skeletonization. To the authors' knowledge, this is the first published report of experimentally observed desiccation in such a form in a Dfb climate. This study provides new data on the types of decomposition patterns to expect in forensic investigations in southern Quebec and comparable climates.

FOXO3 Depletion as a Marker of Compression-Induced Apoptosis in the Ligature Mark: An Immunohistochemical Study.

One of the most challenging issues in forensic pathology is lesion vitality demonstration, particularly in cases of hanging. Over the past few years, immunohistochemistry has been applied to this field with promising results. In particular, protein and transcription factors involved in the apoptotic process have been studied as vitality markers for the ligature mark. This study represents an implementation of our previous studies on ligature mark vitality demonstration. In this study, we evaluated the FOXO3 expression in post-mortem cervical skin samples through an immunohistochemical analysis. To evaluate FOXO3 expression, anti-FOXO3 antibodies (GTX100277) were used. The study group comprised 21 cases, 8 women and 13 men, whereas the control group consisted of 13 cases of subjects who died due to other causes. Decomposition and no clear circumstantial data were exclusion criteria. We found that FOXO3 is decreased in hanging cases compared with normal skin in other causes of death (p-value < 0.05). No differences were seen concerning the type of hanging material (hard or soft), type of hanging (complete or incomplete), and position of the knot. Our results suggest that FOXO3 depletion could be a valid immunohistochemical marker of ligature mark vitality.

Solving the inverse problem of post-mortem interval estimation using Bayesian Belief Networks.

Bayesian Belief Networks (BBNs) can be applied to solve inverse problems such as the post-mortem interval (PMI) by a simple and logical graphical representation of conditional dependencies between multiple taphonomic variables and the observable decomposition effect. This study is the first cross-comparison retrospective study of human decomposition across three different geographical regions. To assess the effect of the most influential taphonomic variables on the decomposition rate (as measured by the Total Decomposition Score (TDS)), decomposition data was examined from the Forensic Anthropology Research Facility at the University of Tennessee (n = 312), the Allegheny County Office of the Medical Examiner in Pittsburgh, US (n = 250), and the Crime Scene Investigation department at Southwest Forensics in the UK (n = 81). Two different BBNs for PMI estimations were created from the US and the UK training data. Sensitivity analysis was performed to identify the most influential parameters of TDS variance, with weaker variables (e.g., age, sex, clothing) being excluded during model refinement. The accuracy of the BBNs was then compared by additional validation cases: US (n = 28) and UK (n = 10). Both models conferred predictive power of the PMI and accounted for the unique combination of taphonomic variables affecting decomposition. Both models had a mean posterior probability of 86% (US) and 81% (UK) in favor of the experimental hypothesis (that the PMI was on, or less than, the prior last known alive date). Neither the US nor the UK datasets represented any cases below 'moderate' support for the value of PMI evidence. By applying coherent probabilistic reasoning to PMI estimations, one logical solution is provided to model the complexities of human decomposition that can quantify the combined effect of several uncertainties surrounding the PMI estimation. This approach communicates the PMI with an associated degree of confidence and provides predictive power on unknown PMI cases.

Applications of artificial intelligence in forensic sciences: Current potential benefits, limitations and perspectives.

In recent years, new studies based on artificial intelligence (AI) have been conducted in the forensic field, posing new challenges and demonstrating the advantages and disadvantages of using AI methodologies to solve forensic well-known problems. Specifically, AI technology has tried to overcome the human subjective bias limitations of the traditional approach of the forensic sciences, which include sex prediction and age estimation from morphometric measurements in forensic anthropology or evaluating the third molar stage of development in forensic odontology. Likewise, AI has been studied as an assisting tool in forensic pathology for a quick and easy identification of the taxonomy of diatoms. The present systematic review follows the PRISMA 2020 statements and aims to explore an emerging topic that has been poorly analyzed in the forensic literature. Benefits, limitations, and forensic implications concerning AI are therefore highlighted, by providing an extensive critical review of its current applications on forensic sciences as well as its future directions. Results are divided into 5 subsections which included forensic anthropology, forensic odontology, forensic pathology, forensic genetics, and other forensic branches. The discussion offers a useful instrument to investigate the potential benefits of AI in the forensic fields as well as to point out the existing open questions and issues concerning its application on real-life scenarios. Procedural notes and technical aspects are also provided to the readers.

Assessing wound vitality in decomposed bodies: a review of the literature.

The capability of discriminating between a vital and a post-mortem injury has always been a central theme in forensic pathology, particularly when the corpse is an advanced state of decomposition. Post-mortem decay of the body can mask or disrupt the classical features of a skin lesion, making it difficult to establish the cause and manner of death. Taphonomically challenging situations pose several interpretative issues of skin lesions which need to be addressed with scientifically recent methods that are still limited in the forensic literature. For that reason, the present research aims at resuming what is currently available in the attempt to provide some insight regarding this topic. This review considers only original researches, in which the markers of vitality were studied a significant amount of time after death, in order to test post-mortem persistency of these markers over time. A number of 132 original articles and reviews were considered, and the most significant results are resumed in an overview table and in two intuitive figures. Though many researchers tried to establish the vitality of lesions in specimen, few analysed samples from bodies when a significant degree of putrefaction or burning had occurred. The most significant marker proved to be GPA, which sowed a satisfying persistence over time (up to 6 months in air putrefaction and 15 days in water). However, what clearly emerged is that further studies are needed to address the challenges of taphonomically transformed specimen and to possibly neutralize the variability of experimental conditions, which affect the reproducibility of results. In conclusion, this study could be a starting point for providing food for thoughts about the most useful markers to search for in unusually tricky autopsy cases.

Utility and diagnostic value of postmortem microbiology associated with histology for forensic purposes.

Nowadays, the diagnostic value of postmortem microbiological investigations is still a debated topic, but postmortem microbiology (PMM) remains a discipline with great forensic potential. To evaluate the usefulness and diagnostic-forensic value of postmortem microbiological cultures, it has been conducted a study on cadaveric material sampled during autopsy aiming to identify the correct cause of death. The study analyzed 45 cadavers subjected to judicial autopsy, divided into two groups based on the presence or absence of external or internal macroscopic autopsy signs suggesting infectious pathology. In the same cases, both the microbiological and conventional histological investigations have been simultaneously carried out. From the investigations, mono-bacterial, mono-fungal, mixed and negative cultures were observed. In mono-species microbiological growth, the histological epicrisis confirmed an infectious cause of death due to the presence of signs of acute infection with an aggressive infectious agent. In cases where growth was mixed, it was possible to distinguish between simple postmortal contamination and perimortem colonization. Finally, in some cases where the microbiology was negative, this has been essential in highlighting signs of a vital reaction to viral or parasitic infection. The joint and integrated evaluation of the laboratory results made it possible to correctly understand even those peculiar situations in which the PMM results alone would not have been significant. These methods, when combined, constitute an optimal forensic approach for the identification of the real cause of death and thus reduce the number of unsolved cases.

[Postmortem computed tomography of the frozen corpse]. / Posmertnaya komp'yuternaya tomografiya oledenevshego trupa.

The purpose of the work is to identify the possibilities of computed tomography in establishing postmortem changes in the bones of the skeleton and internal organs during in a frozen corpse. The article describes a case from thanatological practice with the performance of a pre-sectional computed tomography of a corpse of a young woman found in a forest in a state of complete freezing. As a result of the study, CT images of frozen internal organs were obtained, which are never found in clinical practice. Significant changes in the CT pattern were revealed due to a decrease in the density of the frozen zones. The use of pre-sectional computed tomography enabled to identify postmortem changes in internal organs formed during freezing of the corpse; the position of the corpse during its glaciation and the uniformity of the freezing process.

The Forensic Pathology of the Sexual Abuse of a Group of Chickens.

Twelve chickens were discovered dead in a barn with a human male suspect observed on closed-circuit television. Post-mortem examination of two of the chickens revealed traumatic injury to the ventral cloaca with fibrinoheterophilic coelomitis associated with coelomic contamination by gut contents. The presence of human DNA was subsequently confirmed in cloacal swabs. This report highlights animal sexual abuse, which may occur in a range of species including chickens, as a significant challenge to animal welfare. Veterinary surgeons should be vigilant for signs of injury to the anogenital regions of animal patients, including birds, as evidence of potential sexual abuse.

CiteSpace-Based Visualization Analysis of Forensic Research in China from 2010 to 2019.

OBJECTIVES: To analyze the research status of forensic medicine in China from 2010 to 2019, obtain the development trend of forensic medicine and explore the hotspots and research frontiers. METHODS: The forensic medical academic papers published on China National Knowledge Infrastructure (CNKI) database from 2010 to 2019 were collected. CiteSpace 5.7.R1, an information visualization analysis software, was used to analyze publication organizations, authors, keywords, and other elements. RESULTS: The majority of the research institutions were universities, provincial and ministerial scientific research and forensic institutions. Forensic pathology was still an important branch of forensic medicine and a popular research direction. The "polymorphism" and "Y chromosome" had been the research hotspots in recent years. "Medical damage" and "standard" were the most novel studies. CONCLUSIONS: In order to provide scientific basis and research direction for forensic research, this paper analyzes the cooperation network, research hotspots and research innovation in forensic research.

Forensic Analysis of 9 Cases of Sudden Unexpected Death in Epilepsy.

OBJECTIVES: To analyze the case, scene and forensic pathological characteristics of sudden unexpected death in epilepsy (SUDEP), to provide a practical basis for forensic identification. METHODS: A total of 9 autopsy cases of SUDEP were collected. The basic information of the cases, the scene characteristics, the forensic pathological changes, the common drugs and antiepileptic drug test results, and pericardial fluid biochemical test results were analyzed. RESULTS: All of the 9 cases were male epilepsy patients died during sleep at night, the age of death was (37.1±8.6) years, and the course of epilepsy was (21.3±5.6) years. Six corpses were in prone position and three in left lateral position. The hemorrhage of the sternocleidomastoid muscle, sternal thyroid muscle and sternohyoid muscle were found with 8 cases, 5 cases and 4 cases, respectively, all of them were unilateral. Six cases had bilateral hemorrhage of pectoralis minor muscle. Brain edema, phagocytosis of frontotemporal neurons and gliosis, cardiac fibers bend in wavy patterns and eosinophilic staining enhancement, pulmonary edema, pulmonary congestion, alveolar hemorrhage, pulmonary small bronchiole wall shrinking, tubular proteinuria and pancreatic parenchymal hemorrhage were the common histopathological changes. The biochemical test results of pericardial fluid indicated that there were myocardial ischemic damage. CONCLUSIONS: Young male, early onset, long course of disease, sleep in the prone position, poor drug compliance or combination, epileptic seizure may be the risk factors of SUDEP. Cardiac dysfunction and respiratory depression might be the main death mechanism of SUDEP.

Research Progress of Forensic Diagnosis Approaches of Early Acute Myocardial Infarction.

The postmortem diagnosis of acute myocardial infarction (AMI), especially the postmortem diagnosis of early AMI that died immediately after onset or within 1 hour, has always been a difficulty in forensic identification. This article reviews the forensic application of diagnosis and analysis methods for AMI postmortem diagnosis including autopsy imaging, histomorphology, immunohisto-chemistry, biochemical marker and molecular biology diagnosis, and explores the feasible scheme of early postmortem diagnosis in AMI.

Forensic Research Progress on Postural Asphyxia.

In recent years, the increase in the number of cases of postural asphyxia has gradually attracted the attention and discussion of forensic scientists domestically and internationally, but a systematic, comprehensive and recognized expert consensus and identification standard has not been established at home and abroad. This paper reviews the case characteristics, occurrence, mechanism of death, and identification criteria of postural asphyxia, to provide reference for future research.

Forensic Diagnosis of Freshwater or Saltwater Drowning Using the Marker Aquaporin 5: An Immunohistochemical Study.

Background and Objectives: Aquaporins are a family of water channel proteins. In this study, the renal and intrapulmonary expression of aquaporin-5 (AQP5) was examined in forensic autopsy cases to evaluate it as a drowning marker and to differentiate between freshwater drowning and saltwater drowning. Materials and Methods: Cases were classified into three groups: freshwater drowning (FWD), saltwater drowning (SWD), and controls (CTR). Samples were obtained from forensic autopsies at less than 72 h postmortem (15 FWD cases, 15 SWD cases, and 17 other cases) and were subjected to histological and immunohistochemical investigations. Results: In FWD group, intrapulmonary AQP5 expression was significantly suppressed compared with SWD and CTR; there was no significant difference in AQP5 expression among the other two groups. The same differences in expression were also observed in the kidney. Conclusions: These observations suggest that AQP5 expression in alveolar cells was suppressed by hypotonic water to prevent hemodilution. Moreover, it is possible to hypothesize that in the kidney, with the appearance of hypo-osmotic plasma, AQP5 is hypo-expressed, as a vital reaction, to regulate the renal reabsorption of water. In conclusion, the analysis of renal and intrapulmonary AQP5 expression would be forensically useful for differentiation between FWD and SWD, or between FWD and death due to other causes.