Forensic Science, Medicine and Pathology最新文献

Constipation is characterized by persistent difficulty in defecating. It is a common disorder in the community particularly affecting the elderly and those with intellectual disabilities and neuropsychiatric disorders. It is also caused by numerous medications including analgesic, antidepressant, antihypertensive and anticholinergic agents. It may be asymptomatic or it may produce abdominal pain/cramps, bloating, nausea and anorexia progressing to urinary incontinence and fecal impaction, or paradoxical diarrhea due to overflow. A wide range of mechanisms associated with constipation may result in death including bowel obstruction, stercoral colitis with ulceration, perforation and peritonitis, respiratory compromise, abdominal compartment syndrome and venous thrombosis with pulmonary thromboembolism. Constipation may exacerbate pre-existing diseases and treatments such as laxative and enemas may be lethal. The autopsy examination of a case with constipation and megacolon should take into account all of the pre-existing conditions, as well as the possibility of underlying disorders such as Hirschprung disease. Review of the decedent's medical and drug history and level of supportive care will be important. Toxicological evaluations may be useful.

Purpose: This study aimed to develop an improved method for forensic age estimation using deep learning models applied to orthopantomography (OPG) images, focusing on distinguishing individuals under 12 years old from those aged 12 and above.

Methods: A dataset of 1941 pediatric patients aged between five and 15 years was collected from two radiology departments. The primary research question addressed the identification of the most effective deep learning model for this task. Various deep learning models including Xception, ResNet, ShuffleNet, InceptionV3, DarkNet, NasNet, DenseNet, EfficientNet, MobileNet, ResNet18, GoogleNet, SqueezeNet, and AlexNet were evaluated using traditional metrics like Classification Accuracy (CA), Sensitivity (SE), Specificity (SP), Kappa (K), Area Under the Curve (AUC), alongside a novel Polygon Area Metric (PAM) designed to handle imbalanced datasets common in forensic applications.

Results: "Forensic Xception" model derived from Xception outperformed others, achieving a PAM score of 0.8828. This model demonstrated superior performance in accurately classifying individuals' age groups, with high CA, SE, SP, K, AUC, and F1 Score. Notably, the introduction of the PAM metric provided a comprehensive evaluation of classifier performance.

Conclusion: This study represents a significant advancement in forensic age estimation from OPG images, emphasizing the potential of deep learning models, particularly the "Forensic Xception" model, in accurately classifying individuals based on age, especially in legal contexts. This research suggests a promising avenue for further advancements in forensic dental age estimation, with future studies encouraged to explore additional datasets, refine models, and address ethical and legal considerations.

Fractal burning is a recent form of pyrography (decorative wood burning) using an extremely high voltage applied across a wood surface soaked in an electrolyte solution to produce a ferning or 'Lichtenberg' pattern. Two fatal cases of electrocution are reported in adults engaged in fractal burning to demonstrate characteristic features. Both had evidence of electrical contact with extensive burning. Death can occur following accidental contact with electrodes, the electrolyte solution or a loose wire, or when the victim stands on a conductive floor, or does not wear appropriate protective clothing, or has the wood on a non-insulated surface. Investigators need to check for these issues and to also determine whether the decedent had been appropriately trained in the handling of high voltage equipment.

Congenital left atrial appendage (LAA) aneurysm is an extremely rare condition characterized by abnormal dilatation of the LAA. We report a fatal case of a left atrial appendage aneurysm (LAAA). The presented case was a 19-year-old male who died suddenly during vigorous exercise with no relevant medical or family history. On gross examination, we observed a semi-rounded bulge at the LAA with a diameter of approximately 5 cm. Sectioning the bulge revealed an aneurysmal dilatation encompassing recent and huge lamellated mural thrombi filling its cavity. Though coronaries showed no stenosis, the mid-ventricular section of the heart showed dark and whitish areas at the lateral and posterior wall of the left ventricle, which were suspicious of myocardial infarctions. Histopathological examination depicted a thinned fibrosed wall of LAA, and the mural thrombi exhibited different stages of healing, which was confirmed using Martius Scarlet Blue stain. We identified myocardial infarctions at the suspected areas in the left ventricle, confirmed by the Masson Trichrome stain. The chronic myocardial ischemia was precipitated by the LAA aneurysmal compression of the left circumflex coronary artery as it passed along the atrioventricular groove. Seven other cases who died from LAAA complications since 1922 were reviewed. Early diagnosis and adequate management of LAAA allow survival without residual complications. Yet, this article highlighted the importance of screening for cardiac diseases in those subjected to vigorous exercise.

Hyperspectral imaging (HSI) allows for the contactless analysis of the composition of substances based on the reflected light and is already used in various areas of medicine. The carboxyhemoglobin (CO-Hb) concentration in blood of suspected fire victims serves to prove vitality and the cause of death. However, this metric is usually determined by spectrophotometry in the laboratory. The present study provides the basis for the future development of methods for determining CO-Hb concentrations right at the scene of a corpse or at necropsy using mobile HSI. Human erythrocyte concentrate was mixed with gaseous carbon monoxide using an aerator to produce a series of samples, which were analyzed for their CO-Hb concentration (2.9; 9.7; 18; 27.9; 39.9; 51.9; 62.3; 73.4% CO-Hb) using established spectrophotometric blood gas analysis. These blood samples were stored in a cool place at 4 °C, dripped onto a spot plate every 7 days over a period of 6 weeks, and photographed under standardized conditions (ambient lighting, distance and angle of the camera to the sample, camera settings) using the HSI camera SPECIM IQ. This device analyzes each image in the wavelength range from 400 to 1000 nm in 204 spectral bands. The data sets were used to train a lasso regression model, which provides predicted values for the CO-Hb concentration of the blood sample based on their hyperspectral properties. The results were then compared with the results of spectrophotometric measurements. The lasso regression model allowed the prediction of the CO-Hb concentration of the samples with a mean prediction error of 4.46 percentage points, independent of the sample age. Further investigations regarding pre-analytical influencing factors such as variable ambient light and tissue scattering effects, are planned to validate the robustness of the method and realize practical implementations.

Sudden cardiac death (SCD) is a major public health concern. In sub-Saharan Africa (SSA), including South Africa, there is a lack of reliable statistics on the incidence of SCD, even though there has been a fourfold increase in noncommunicable diseases (NCD), particularly cardiovascular diseases (CVD). Sudden cardiac death contributes to an estimated 50% of all cardiovascular deaths, which highlights South Africa's need for research into better detection, treatment and prevention. This study aimed to identify an inherited cardiac arrhythmogenic disorder, linked to variants in cardiomyopathy- and arrhythmia-related genes, as a potential contributing factor to sudden cardiac deaths. DNA was extracted from blood samples collected at autopsy of 51 sudden unexpected death (SUD) cases, and subjected to next-generation sequencing (NGS) of 49 genes linked to inherited cardiac arrhythmogenic disorders. Variants were annotated and interpretated for clinical significance using the Galaxy bioinformatic platform. In total, 175 different missense variants were identified in the study population (n = 51). Of these, 92.5% (162/175) were known, documented variants, and the remaining 7.4% (13/175) were considered novel. Of the known variants, 78.4% (127/162) were of benign/likely benign significance, 20.4% (33/162) were variants of unknown significance (VUS), and 1.2% (2/162) was pathogenic. The 13 novel variants were analysed using online prediction software, with 92.3% (12/13) predicted to be likely benign and 7.7% (1/13) grouped into the VUS category. Post-mortem genetic testing provided evidence of a genetic arrhythmic/cardiac conduction disorder as the probable pathogenic basis for approximately 4% (2/51) of sudden unexpected death (SUD) cases.

Unidentified human remains are frequently found in missing person cases, necessitating identification for forensic purposes and to inform the next of kin. Traditional postmortem fingerprinting methods depend on intact surface fingerprints, which are often compromised by decomposition. A viable alternative is to use internal fingerprints (a blueprint of the surface fingerprint located just below the epidermis) instead. This study assessed the utility of Optical Coherence Tomography (OCT) as a means to record internal fingerprints from excavated human fingers. Conducted at the Amsterdam human taphonomic test site, the investigation comprised two longitudinal studies and two in situ burial scenarios. Human fingers were buried, excavated, and scanned using OCT at various time intervals. Internal fingerprints could be recorded up to 7 days longer than surface fingerprints, with a maximum of 10 days post-burial. These internal fingerprints provided higher minutiae counts, suitable for Automated Fingerprint Identification System (AFIS) searches. Additionally, in one case, fingerprints were successfully extracted after 13 weeks and 10 months of in situ burial. This demonstrates OCT's potential to enhance postmortem fingerprinting for identifying human remains in forensic investigations.

During excavation campaigns carried out in north-eastern Spain (Aragonese), a well -preserved late 18th century infant mummy was exhumed from the topsoil of El Piquete church (Quinto, Zaragoza). At morphological macroscopical observation, a penetrating lesion lateral to the right knee was identified. The lesion was covered by linen bindings with a circumscribed brownish discoloration. Investigations were carried out with a special focus on the lower tight lesion in order to ascertain whether it had occurred intra-vitam, perimortem or post-mortem. A CT scan was performed to establish the age at death of the infant and to identify possible pathological disorders of the skeleton and internal organs. Histology was performed on the ovoid, deep penetrating lesion in order to determine whether it was vital or was due to taphonomic alterations. The body belonged to a male, 12-16 months old infant. It did not show any pathological disorder apart from the presence of an ovoid deep penetrating skin lesion lateral to the right knee. Histology showed that, apart from the typical postmortem alterations, several small haemosiderin deposits, such as in siderophages, were present, thus indicating, not only the vitality of the ulceration, but also its age of more than several days. We conclude that the infant survived the traumatic lesion for a few days and he most likely died of systemic infection related syndrome (SIRS). This rare case adds to the paleopathological literature on children's possible cause of death.

Estimation of the postmortem interval (PMI) is highly significant, and many estimation methods have been developed. However, as no estimation method is determinate, several methods must be combined to achieve an accurate estimation. Therefore, the more methods available, the more accurate the estimation. To facilitate this, we examined whether red cell distribution width standard deviation (RDW-SD) was associated with PMI. We compared the RDW-SDs of blood samples from hospitals and autopsies in the same cadavers using a paired test. Additionally, we performed an unpaired test with multiple regression analysis to confirm the relationship between PMI and RDW-SD. Eighteen cases were included in the paired analysis, and a significant difference between hospital and autopsy RDW-SDs was confirmed. The 95% confidence interval for the difference was between 11.7 and 17.4. In the multiple regression analysis of the 756 cadavers, the 95% confidence interval of the regression coefficient of PMI for RDW-SD was 1.63-3.43. Our results suggest that RDW-SD may have a positive relationship with PMI. However, further research is required to determine the accuracy of this estimation method.

Sudden unexpected infant death (SUID) encompasses both explained and unexplained infant fatalities. When a comprehensive investigation yields inconclusive results, the case is classified as sudden infant death syndrome (SIDS). On the other hand, the most frequent non-SIDS diagnoses may be attributed to specific causes of death including a heterogeneous spectrum of conditions and disorders (e.g., trauma, asphyxia, suffocation, infection and metabolic diseases). Although rare, milk aspiration is a recognized cause of SUID that can lead to acute respiratory failure. This case report describes the death of a three-month-old infant found unresponsive in a traditional African baby carrier. Gross examination revealed no significant anomalies other than increased lung weight and the presence of milk-like material in the airways, alveoli, and stomach. Histological and ultrastructural analyses identified granular brownish material with birefringent globules in the lungs, consistent with aspirated milk. Immunohistochemical staining was positive for beta-lactoglobulin, confirming formula milk aspiration. This evidence was crucial in excluding maternal negligence as a cause of death, instead supporting an ante-mortem aspiration event resulting from regurgitation. This case highlights the diagnostic challenges associated with fatal milk aspiration and emphasizes the critical importance of a multidisciplinary approach. The integration of clinical history, autopsy findings, and advanced histopathological techniques is essential for accurately determining the cause of death and ensuring a sound legal assessment within the Courtroom setting.