Forensic Pathology of Traumatic Brain Injury

A Mouse Model of Temporal Lobe Contusion

Trauma to the brain can induce a contusion characterized by a discrete intracerebral or diffuse interstitial hemorrhage. In humans, "computed tomography-positive," that is, hemorrhagic, temporal lobe contusions (tlCont) have unique sequelae. TlCont confers significantly increased odds for moderate or worse disability and the inability to return to baseline work capacity compared to intra-axial injuries in other locations. Patients with tlCont are at elevated risks of memory dysfunction, anxiety, and post-traumatic epilepsy due to involvement of neuroanatomical structures unique to the temporal lobe including the amygdala, hippocampus, and ento-/perirhinal cortex. Because of the relative inaccessibility of the temporal lobe in rodents, no preclinical model of tlCont has been described, impeding progress in elucidating the specific pathophysiology unique to tlCont. Here, we present a minimally invasive mouse model of tlCont with the contusion characterized by a traumatic interstitial hemorrhage. Mortality was low and sensorimotor deficits (beam walk, accelerating rotarod) resolved completely within 3-5 days. However, significant deficits in memory (novel object recognition, Morris water maze) and anxiety (elevated plus maze) persisted at 14-35 days and nonconvulsive electroencephalographic seizures and spiking were significantly increased in the hippocampus at 7-21 days. Immunohistochemistry showed widespread astrogliosis and microgliosis, bilateral hippocampal sclerosis, bilateral loss of hippocampal and cortical inhibitory parvalbumin neurons, and evidence of interhemispheric connectional diaschisis involving the fiber bundle in the ventral corpus callosum that connects temporal lobe structures. This model may be useful to advance our understanding of the unique features of tlCont in humans.

Hydrogel in the Treatment of Traumatic Brain Injury

The high prevalence of traumatic brain injury (TBI) poses an important global public health challenge. Current treatment modalities for TBI primarily involve pharmaceutical interventions and surgical procedures; however, the efficacy of these approaches remains limited. In the field of regenerative medicine, hydrogels have garnered significant attention and research efforts. This review provides an overview of the existing landscape and pathological manifestations of TBI, with a specific emphasis on delineating the therapeutic potential of hydrogels incorporated with various bioactive agents for TBI management. Particularly, the review delves into the utilization and efficacy of hydrogels based on extracellular matrix (ECM), stem cell-loaded, drug-loaded, self-assembled peptide structures or conductive in the context of TBI treatment. These applications are shown to yield favorable outcomes such as tissue damage mitigation, anti-inflammatory effects, attenuation of oxidative stress, anti-apoptotic properties, promotion of neurogenesis, and facilitation of angiogenesis. Lastly, a comprehensive analysis of the merits and constraints associated with hydrogel utilization in TBI treatment is presented, aiming to steer and advance future research endeavors in this domain.

The effect of Centella asiatica, cinnamon, and spirulina as neuroprotective based on histopathological findings in ratus Sprague Dawley with traumatic brain injury

Background

Traumatic brain injury (TBI) is a global health problem with the potential to cause dangerous neurological problems. Based on histopathological findings in Sprague Dawley (SD) rats with TBI in the acute phase, the study seeks to discover the effect of Centella asiatica, cinnamon, and spirulina as neuroprotective.

Methods

We conducted an experimental study with 30 SD rats randomly divided into three groups. The intervention was the administration of C. asiatica, cinnamon, and spirulina to the control and the experimental groups. Histological features were assessed using hematoxylin and eosin (H&E) staining and immunohistochemical examination. The data were analyzed using statistical analysis through correlation tests.

Results

The test samples' average body weights had P > 0.05, indicating no significant difference in the test sample body weights. Therefore, the variations in the expression level of the dependent variable were expected to be caused by the induction of brain injury and the administration of C. asiatica, cinnamon, and spirulina. In addition, the variables were not normally distributed. Thus, the Spearman test was carried out and showed the correlation was very strong, with a value of r = 0.818 and P < 0.05.

Conclusion

Based on histopathological findings from the brains of SD rats with TBI, pegagan, cinnamon, and spirulina will protect the brain (neuroprotective) in the acute phase.

The significance of shooting angle in seal shooting

The present study aimed to investigate the relationship between shooting angle to the head and animal welfare outcomes in the hunt of young harp seals (Pagophilus groenlandicus). The study population consisted of young harp seals belonging to the Greenland Sea harp seal population. A sample of 171, 2-7 weeks old, weaned harp seals of both sexes were included. The study was conducted as an open, randomised parallel group designed trial during the regular hunt. The animals were allocated into four groups, A-D, according to the observed shooting angle to the head, defined as the angle between the direction of the shot and the longitudinal axis of the animal's head: (A) directly from the front; (B) obliquely from the front; (C) directly from the side; and (D) obliquely or directly from behind. Instantaneous death rate (IDR) and time to death (TTD) were the main variables. The mean IDR differed significantly between groups and was highest in group B (96.8%) and lowest in group C (66.7%). For all groups combined it was 84.2%. The mean TTD for seals not rendered instantaneously unconscious or dead (n = 27) differed significantly between groups and was shortest in group A (16 s) and longest in group C (85 s). However, the number of animals included in the TTD analysis was limited. In conclusion, based on the significantly higher IDR, the shooting angle obliquely from the front is recommended to help achieve the best animal welfare outcomes during the hunt of young harp seals.

Depressed skull fracture compressing eloquent cortex causing focal neurologic deficits

BACKGROUND

Depressed skull fractures are typically the consequence of high-impact injuries with inward buckling of the cranium. The majority of depressed skull fractures are managed conservatively in the absence of dural violation, sinus involvement, significant underlying hematoma, depressed fragment greater than 1 cm, wound infection, or gross wound contamination. Even in the presence of any of the aforementioned criteria, cranioplasty is typically considered an urgent procedure rather than a neurosurgical emergency. Rarely, a depressed fracture fragment can cause focal neurologic deficit(s) due to direct compression of the underlying eloquent cortex.

CASE DESCRIPTION

A 40-year-old male presented to the emergency department after a mechanical fall with a left central facial nerve palsy, left hemiplegia, left hemianesthesia, and fixed right gaze deviation. The neurologic deficits observed were attributed to a combination of blunt force trauma to the head (i.e., coup-contrecoup injury) and the depressed fracture fragment compressing the underlying eloquent cortex. He underwent emergent cranioplasty with fragment elevation within 2 hours of the traumatic injury. At 6-month follow-up, he regained full neurologic function without any residual deficits.

CONCLUSIONS

Our experience highlights a rare indication for emergent cranioplasty with an excellent functional outcome attributable to immediate fracture elevation and decompression of eloquent cortex.

A Systematic Review on Traumatic Brain Injury Pathophysiology and Role of Herbal Medicines in its Management

BACKGROUND

Traumatic brain injury (TBI) is a worldwide problem. Almost about sixtynine million people sustain TBI each year all over the world. Repetitive TBI linked with increased risk of neurodegenerative disorder such as Parkinson, Alzheimer, traumatic encephalopathy. TBI is characterized by primary and secondary injury and exerts a severe impact on cognitive, behavioral, psychological and other health problem. There were various proposed mechanism to understand complex pathophysiology of TBI but still there is a need to explore more about TBI pathophysiology. There are drugs present for the treatment of TBI in the market but there is still need of more drugs to develop for better and effective treatment of TBI, because no single drug is available which reduces the further progression of this injury.

OBJECTIVE

The main aim and objective of structuring this manuscript is to design, develop and gather detailed data regarding about the pathophysiology of TBI and role of medicinal plants in its treatment.

METHOD

This study is a systematic review conducted between January 1995 to June 2021 in which a consultation of scientific articles from indexed periodicals was carried out in Science Direct, United States National Library of Medicine (Pubmed), Google Scholar, Elsvier, Springer and Bentham.

RESULTS

A total of 54 studies were analyzed, on the basis of literature survey in the research area of TBI.

CONCLUSION

Recent studies have shown the potential of medicinal plants and their chemical constituents against TBI therefore, this review targets the detailed information about the pathophysiology of TBI and role of medicinal plants in its treatment.

Post-traumatic cerebral infarction caused by thrombus in the middle cerebral artery

A woman in her 80s was found unconscious after being hit by a car while crossing a road. After admission to hospitals, computed tomography (CT) scans revealed traumatic brain injury (TBI), and the patient was treated symptomatically. However, despite improvement of TBI in CT images, she died unexpectedly. Postmortem CT demonstrated cerebral infarction in the territory of the right middle cerebral artery (MCA). Histopathological examination revealed lumen-obstructing thrombosis and intimal injury upstream of the thrombosis in the right MCA. These findings suggested that the intimal injury in the MCA had led to thrombus formation, and thromboembolism in the region distal to the injury leading to post-traumatic cerebral infarction (PTCI). Both postmortem CT and autopsy were able to reveal the final condition of the deceased, which had not been fully anticipated by the clinicians who had treated her after the accident. The longitudinal antemortem to postmortem course revealed by multiple CT images and the histopathological examination provided crucial clues to the pathogenesis of PTCI in this case.

Pathogen Screening for Possible Causes of Meningitis/Encephalitis in Wild Carnivores From Saxony-Anhalt

Inflammation in meninges and/or brain is regularly noticed in red foxes and other wild carnivores during rabies control programs. Despite negative rabies virus (RABV) results, the etiologies of these cases remain unknown. Thus, the aim of this study was to provide an overview of the occurrence of pathogens that may cause diseases in the brains of wild carnivores and pose a risk to humans and other animals. In addition to RABV and canine distemper virus (CDV), a variety of pathogens, including members of Flaviviridae, Bornaviridae, Herpesviridae, Circoviridae, as well as bacteria and parasites can also cause brain lesions. In 2016 and 2017, brain samples of 1,124 wild carnivores were examined by direct fluorescent antibody test for RABV as well as (reverse-transcriptase) quantitative polymerase chain reaction (PCR) for the presence of CDV as part of a monitoring program in Saxony-Anhalt, Germany. Here, we applied similar methods to specifically detect suid herpesvirus 1 (SuHV-1), West Nile virus (WNV), Borna disease virus 1 (BoDV-1), canid alphaherpesvirus 1 (CaHV-1), canine parvovirus type 2 (CPV-2), fox circovirus (FoxCV), and Neospora caninum (N. caninum). Further, bacteriogical examination for the existence of Listeria monocytogenes (L. monocytogenes) and immunohistochemistry of selected cases to detect Toxoplasma gondii (T. gondii) antigen were performed. Of all pathogens studied, CDV was found most frequently (31.05%), followed by FoxCV (6.80%), CPV-2 (6.41%), T. gondii (4/15; 26.67%), nematode larvae (1.51%), L. monocytogenes (0.3%), and various other bacterial pathogens (1.42%). In 68 of these cases (6.05%), multiple pathogen combinations were present simultaneously. However, RABV, WNV, BoDV-1, SuHV-1, CaHV-1, and N. caninum were not detected. The majority of the histopathological changes in 440 animals were inflammation (320/440; 72.73%), predominantly non-suppurative in character (280/320; 87.50%), and in many cases in combination with gliosis, satellitosis, neuronophagia, neuronal necrosis, and/or vacuolization/demyelination, or in single cases with malacia. Thus, it could be shown that wild carnivores in Saxony-Anhalt are carriers mainly for CDV and sometimes also for other, partly zoonotic pathogens. Therefore, the existing monitoring program should be expanded to assess the spill-over risk from wild carnivores to humans and other animals and to demonstrate the role of wild carnivores in the epidemiology of these zoonotic pathogens.

Dynamics of neutrophil-to-lymphocyte ratio can be associated with clinical outcomes of children with moderate to severe traumatic brain injury: A retrospective observational study

BACKGROUND

The neutrophil to lymphocyte ratio (NLR) has been reported to be associated with clinical outcomes of patients with severe traumatic brain injury (TBI). This study aimed to evaluate the correlation between the dynamics of NLR and clinical outcomes of pediatric patients with moderate to severe TBI.

METHODS

We retrospectively evaluated the clinical data of a total of 374 pediatric patients with moder-ate to severe TBI who were treated in our department between May 2016 and May 2020. Clinical and laboratory data including the NLR upon admission and the NLR on hospital day four were collected. Poor clinical outcome was defined as Glasgow Outcome Scale (GOS) of 1-3. Multivariable logistic regression analyses were performed to investigate the correlation between the dynamics of NLR and clinical outcome.

RESULTS

Three hundred seventy-four pediatric patients (mean age 7.37 ± 3.11, 52.7% male) were evaluated. Based on the ROC curves, a value of 5 was determined as the NLR cut-off value. The corresponding cutoff value for delta NLR was 1. The Glasgow Coma Scale (GCS) (OR, 3.42; 95% CI: 1.88-5.28; P <0.001), the light reflex (OR, 1.79; 95% CI: 1.34- 2.84; P = 0.027), the Rotterdam CT score (OR, 2.71; 95% CI: 1.72-4.13; P = 0.021), and delta NLR (OR, 1.71; 95% CI: 1.13- 2.52; P = 0.034) were identified as independent predictors for unfavorable outcomes in multivariable logistic regression analysis.

CONCLUSIONS

The result of the present study suggest that delta NLR could be a predictor of poor clinical outcome of pediatrics with moderate to severe TBI. This cost-effective and easily available biomarker could be used to predict clinical outcomes in these patients.

Non-thrombotic pulmonary embolism of brain, liver, or bone marrow tissues associated with traumatic injuries in free-ranging neotropical primates

From 2016 to 2019, Southeastern Brazil faced an outbreak of yellow fever (YF) affecting both humans and New World primates (NWP). The outbreak was associated with a marked increase in traumatic lesions in NWP in the affected regions. Non-thrombotic pulmonary embolization (NTPE) can be a consequence of massive traumatic events, and it is rarely reported in human and veterinary medicine. Here, we describe NTPE of the brain, liver, and bone marrow in free-ranging NWP, highlighting the epidemiological aspects of these findings and the lesions associated with this condition, including data on traumatic injuries in wild NWP populations during the course of a recent YF outbreak. A total of 1078 NWP were necropsied from January 2017 to July 2019. Gross traumatic injuries were observed in 444 marmosets (44.3%), 10 howler monkeys (23.2%), 9 capuchins (31.0%), 1 titi-monkey (50.0%), and 1 golden lion tamarin (33.3%). NTPE was observed in 10 animals, including 9 marmosets (2.0%) and 1 howler monkey (10.0%). NTPE was identified in the lung and comprised hepatic tissue in 1 case, brain tissue in 1 case, and bone marrow tissue in 8 cases. Although uncommon, it is important to consider NTPE with pulmonary vascular occlusion during the critical care of traumatized NWP. In addition, this study highlights the importance of conservational strategies and environmental education focusing on One Health, not only to protect these free-ranging NWP populations but also to maintain the efficacy of epidemiological surveillance programs.

On-farm culling methods used for pigs

The culling of injured and non-viable pigs (Sus scrofa) (neonate to breeding stock) is a routine and necessary procedure on most farms. Usually, pigs are culled using one of the following methods: blunt-force trauma (manual and mechanical), captive-bolt stunners, electrical stunning and electrocution or carbon dioxide. Manual blunt-force trauma is one of the most widely used methods due to its low or absent operational and investment costs. However, as a method, it has serious limitations, which include the risk of incomplete concussion, pain, and distress. Manual blunt-force trauma is also aesthetically unpleasant to operators and wider society. To address these issues there has been significant recent research into the development of alternatives to manual blunt-force trauma, these include: captive-bolt stunners, on-farm, gas-based controlled atmosphere systems, low atmospheric pressure systems and electrical stunning. Some of these are currently in commercial use while others are still in the developmental phase. This review brings together the relevant research in this field, evaluating the methods in terms of mechanism of action (mechanical and physiological), effectiveness and animal welfare.

Sudden death after facial impacts: Is the brainstem involved?

Three deaths following facial impacts in the presence of witnesses and resulting in brain lesions that were visualized only on pathological examination were studied at the forensic medicine institute of Marseille. Craniofacial impacts, even of low intensity, received during brawls may be associated with brain lesions ranging from a simple knock-out to fatal injuries. In criminal cases that are brought to court, even by autopsy it is still difficult to establish a direct link between the violence of the impact and the injuries that resulted in death. During a facial impact, the head undergoes a movement of violent forced hyperextension. Death may thus be secondary to the transmission of forces to the brain, either by a mechanism involving nerve conduction that may be termed a reflex mechanism (for example by vagal hyperstimulation) or by injury to the central nervous system (axonal damage). In such situations, autopsy does not make it possible to determine the cause of death, but only to suspect it in a context of voluntary violence in the presence of witnesses, with or without violent injury observed on external examination or on superficial incisions to determine the extent of bruises or hematoma. Systemic and comprehensive investigation involving pathology and toxicology is essential in any medicolegal case for positive interpretation and discrimination of other causes of death.

Proton extrusion during oxidative burst in microglia exacerbates pathological acidosis following traumatic brain injury

Acidosis is among the least studied secondary injury mechanisms associated with neurotrauma. Acute decreases in brain pH correlate with poor long‐term outcome in patients with traumatic brain injury (TBI), however, the temporal dynamics and underlying mechanisms are unclear. As key drivers of neuroinflammation, we hypothesized that microglia directly regulate acidosis after TBI, and thereby, worsen neurological outcomes. Using a controlled cortical impact model in adult male mice we demonstrate that intracellular pH in microglia and extracellular pH surrounding the lesion site are significantly reduced for weeks after injury. Microglia proliferation and production of reactive oxygen species (ROS) were also increased during the first week, mirroring the increase in extracellular ROS levels seen around the lesion site. Microglia depletion by a colony stimulating factor 1 receptor (CSF1R) inhibitor, PLX5622, markedly decreased extracellular acidosis, ROS production, and inflammation in the brain after injury. Mechanistically, we identified that the voltage‐gated proton channel Hv1 promotes oxidative burst activity and acid extrusion in microglia. Compared to wildtype controls, microglia lacking Hv1 showed reduced ability to generate ROS and extrude protons. Importantly, Hv1‐deficient mice exhibited reduced pathological acidosis and inflammation after TBI, leading to long‐term neuroprotection and functional recovery. Our data therefore establish the microglial Hv1 proton channel as an important link that integrates inflammation and acidosis within the injury microenvironment during head injury.

Noninvasive 7 tesla MRI of fatal craniocerebral gunshots - a glance into the future of radiologic wound ballistics

Compared to computed tomography (CT), magnetic resonance imaging (MRI) provides superior visualization of the soft tissue. Recently, the first 7 Tesla (7 T) MRI scanner was approved for clinical use, which will facilitate access to these ultra-high-field MRI scanners for noninvasive examinations and scientific studies on decedents. 7 T MRI has the potential to provide a higher signal-to-noise ratio (SNR), a characteristic that can be directly exploited to improve image quality and invest in attempts to increase resolution. Therefore, evaluating the diagnostic potential of 7 T MRI for forensic purposes, such as assessments of fatal gunshot wounds, was deemed essential. In this article, we present radiologic findings obtained for craniocerebral gunshot wounds in three decedents. The decedents were submitted to MRI examinations using a 7 T MRI scanner that has been approved for clinical use and a clinical 3 T MRI scanner for comparison. We focused on detecting tiny injuries beyond the wound tract caused by temporary cavitation, such as microbleeds. Additionally, 7 T T₂-weighted MRI highlighted a dark (hypo intense) zone beyond the permanent wound tract, which was attributed to increased amounts of paramagnetic blood components in damaged tissue. Microbleeds were also detected adjacent to the wound tract in the white matter on 7 T MRI. Based on the findings of radiologic assessments, the advantages and disadvantages of postmortem 7 T MRI compared to 3 T MRI are discussed with regard to investigations of craniocerebral gunshot wounds as well as the potential role of 7 T MRI in the future of forensic science.

Histologic safety of transcranial focused ultrasound neuromodulation and magnetic resonance acoustic radiation force imaging in rhesus macaques and sheep

BACKGROUND

Neuromodulation by transcranial focused ultrasound (FUS) offers the potential to non-invasively treat specific brain regions, with treatment location verified by magnetic resonance acoustic radiation force imaging (MR-ARFI).

OBJECTIVE

To investigate the safety of these methods prior to widespread clinical use, we report histologic findings in two large animal models following FUS neuromodulation and MR-ARFI.

METHODS

Two rhesus macaques and thirteen Dorset sheep were studied. FUS neuromodulation was targeted to the primary visual cortex in rhesus macaques and to subcortical locations, verified by MR-ARFI, in eleven sheep. Both rhesus macaques and five sheep received a single FUS session, whereas six sheep received repeated sessions three to six days apart. The remaining two control sheep did not receive ultrasound but otherwise underwent the same anesthetic and MRI procedures as the eleven experimental sheep. Hematoxylin and eosin-stained sections of brain tissue (harvested zero to eleven days following FUS) were evaluated for tissue damage at FUS and control locations as well as tissue within the path of the FUS beam. TUNEL staining was used to evaluate for the presence of apoptosis in sheep receiving high dose FUS.

RESULTS

No FUS-related pre-mortem histologic findings were observed in the rhesus macaques or in any of the examined sheep. Extravascular red blood cells (RBCs) were present within the meninges of all sheep, regardless of treatment group. Similarly, small aggregates of perivascular RBCs were rarely noted in non-target regions of neural parenchyma of FUS-treated (8/11) and untreated (2/2) sheep. However, no concurrent histologic abnormalities were observed, consistent with RBC extravasation occurring as post-mortem artifact following brain extraction. Sheep within the high dose FUS group were TUNEL-negative at the targeted site of FUS.

CONCLUSIONS

The absence of FUS-related histologic findings suggests that the neuromodulation and MR-ARFI protocols evaluated do not cause tissue damage.

Brain Tissue Pulmonary Embolism Due to Severe Blunt Force Head Trauma in a Dog

A 9-week-old male puppy was submitted for necropsy examination after a reported history of developing acute melaena and vomiting blood before death. Grossly, the animal had multiple skull fractures, mostly affecting the occipital region and cranial floor, associated with extensive regions of subcutaneous, periosteal and subdural haemorrhages, as well as petechial haemorrhages within the right middle and caudal lung lobes. Histopathology of the brain revealed multifocal acute meningeal and parenchymal haemorrhage with laceration of the cerebellar folia. In the lung, multiple small- and medium-calibre branches of pulmonary arteries were occluded by aggregates of brain tissue, which exhibited weak immunoreactivity for glial fibrillary acidic protein and strong labelling for neuron specific enolase on immunohistochemistry. These findings were consistent with brain tissue pulmonary embolism, an infrequent phenomenon following severe head trauma. To the best of the authors' knowledge, this is the first reported case of canine brain tissue pulmonary embolism.

Traumatic Brain Injury: A Forensic Approach: A Literature Review

Traumatic brain injury (TBI) is the principal cause of invalidity and death in the population under 45 years of age worldwide. This mini-review aims to systematize the forensic approach in neuropathological studies, highlighting the proper elements to be noted during external, radiological, autoptical, and histological examinations with particular attention paid to immunohistochemistry and molecular biology. In the light of the results of this mini-review, an accurate forensic approach can be considered mandatory in the examination of suspected TBI with medico-legal importance, in order to gather all the possible evidence to corroborate the diagnosis of a lesion that may have caused, or contributed to, death. From this point of view, only the use of an evidence-based protocol can reach a suitable diagnosis, especially in those cases in which there are other neuropathological conditions (ischemia, neurodegeneration, neuro-inflammation, dementia) that may have played a role in death. This is even more relevant when corpses, in an advanced state of decomposition, are studied, where the radiological, macroscopic and histological analyses fail to give meaningful answers. In these cases, immune-histochemical and molecular biology diagnostics are of fundamental importance and a forensic neuropathologist has to know them. Particularly, MiRNAs are promising biomarkers for TBI both for brain damage identification and for medico-legal aspects, even if further investigations are required to validate the first experimental studies. In the same way, the genetic substrate should be examined during any forensic examination, considering its importance in the outcome of TBI.

The rise of veterinary forensics

Veterinary forensics is rapidly emerging as a distinct branch of veterinary medicine, especially because of increasing mindfulness about animal cruelty, and of the link between acts of cruelty to animals and violence toward humans. Nevertheless, the application of forensic sciences in veterinary cases lags behind its application in medical cases. Although gaps persist in veterinarians' knowledge of forensics and in how to apply this field to medicolegal cases involving animals, continued research and publication in veterinary forensics are rapidly developing the evidence base in this area. Additionally, educational opportunities in veterinary forensics are also increasing at both undergraduate and postgraduate levels. Together, these changes will continue to improve veterinarians' abilities to investigate cases involving animals. To further strengthen these investigations, veterinarians should also collaborate with the appropriate experts in different disciplines of forensic science.

Treatment of Traumatic Depressed Compound Skull Fractures

BACKGROUND

A skull fracture widely occurs in patients with traumatic brain injury, leading to intracranial hematoma, brain contusion, and intracranial infection. It also influences the prognosis and death of patients. This study aimed to discuss cases of patients with comminuted skull fractures.

METHODS

From October 2015 to December 2018, 38 patients with comminuted skull fractures were admitted to the hospital. All patients underwent three-dimensional reconstruction of computed tomography scan images. Digital subtraction angiography or magnetic resonance venography was performed to find out the venous sinus. The clinical findings of the patients were significant regarding gender, age, injury mechanism, location, admission Glasgow Coma Scale (GCS), combined epidural, subdural, cerebral contusion, intracranial pneumatosis, maximum depth of depression, admission to surgery, dural tear, post-operative cerebrospinal fluid leakage, post-operative infection, and Glasgow Outcome Scale (GOS) 3 months after surgery.

RESULTS

The incidence of traffic accidents, fall from a height, railway accidents, fall of an object, and chop injury was 60.5%, 18.4%, 13.2%, 5.3%, and 2.6%, respectively. Intra-operative dural trar negatively correlated with epidural hematoma, cerebral contusion, and subdural hematoma. Also, post-operative infection negatively correlated with intracranial pneumatosis, depth of fracture depression, and pre-operative cerebrospinal fluid leakage. No correlation was found between contusion, subdural hematoma, intracranial pneumatosis, depth of fracture depression, and post-operative infection. The GOS score positively correlated with age, pre-operative cerebrospinal fluid leakage, and admission GCS score.

CONCLUSIONS

A perfect pre-operative examination is a key to successful surgery. Further studies should be conducted to find out more effective treatments for traumatic comminuted skull fractures.

Histology of Brain Trauma and Hypoxia-Ischemia

Forensic pathologists encounter hypoxic-ischemic (HI) brain damage or traumatic brain injuries (TBI) on an almost daily basis. Evaluation of the findings guides decisions regarding cause and manner of death. When there are gross findings of brain trauma, the cause of death is often obvious. However, microscopic evaluation should be used to augment the macroscopic diagnoses. Histology can be used to seek evidence for TBI in the absence of gross findings, e.g., in the context of reported or suspected TBI. Estimating the survival interval after an insult is often of medicolegal interest; this requires targeted tissue sampling and careful histologic evaluation. Retained tissue blocks serve as forensic evidence and also provide invaluable teaching and research material. In certain contexts, histology can be used to demonstrate nontraumatic causes of seemingly traumatic lesions. Macroscopic and histologic findings of brain trauma can be confounded by concomitant HI brain injury when an individual survives temporarily after TBI. Here we review the histologic approaches for evaluating TBI, hemorrhage, and HI brain injury. Amyloid precursor protein (APP) immunohistochemistry is helpful for identifying damaged axons, but patterns of damage cannot unambiguously distinguish TBI from HI. The evolution of hemorrhagic lesions will be discussed in detail; however, timing of any lesion is at best approximate. It is important to recognize artifactual changes (e.g., dark neurons) that can resemble HI damage. Despite the shortcomings, histology is a critical adjunct to the gross examination of brains.

Euthanasia of Cattle: Practical Considerations and Application

Simple Summary

Methods recognized as acceptable for the euthanasia of cattle include overdose of an anesthetic, gunshot and captive bolt. The most common injectable anesthetic agent used for euthanasia is pentobarbital and while it may be the preferred method for euthanasia in sensitive situations, it creates significant challenges for disposal of animal remains. Gunshot and captive bolt are the more common methods used on farms and ranches because they are inexpensive, humane and do not complicate carcass disposal. Firearms must be of the proper caliber and loaded with the proper ammunition. Captive bolt, equipped with a penetrating bolt, is to be used on adult animals, whereas the non-penetrating (mushroom head) bolt should be reserved for use in calves (three months of age or less). In addition to selection of the proper firearm or captive bolt, successful euthanasia requires use of the proper anatomic site and adjunctive steps to assure death. The indicators of unconsciousness and death must be clearly understood and confirmed in all situations involving euthanasia. Tools for the efficient depopulation of a large feedlot, dairy or beef cattle operation as may be required in a national animal health emergency situation have been developed and validated as effective. Finally, the human impact of euthanasia cannot be underestimated. Symptoms of mental illness including depression, grief, sleeplessness and destructive behaviors including alcoholism and drug abuse are not uncommon for those who participate in the euthanasia of animals.

Abstract

Acceptable methods for the euthanasia of cattle include overdose of an anesthetic, gunshot and captive bolt. The use of anesthetics for euthanasia is costly and complicates carcass disposal. These issues can be avoided by use of a physical method such as gunshot or captive bolt; however, each requires that certain conditions be met to assure an immediate loss of consciousness and death. For example, the caliber of firearm and type of bullet are important considerations when gunshot is used. When captive bolt is used, a penetrating captive bolt loaded with the appropriate powder charge and accompanied by a follow up (adjunctive) step to assure death are required. The success of physical methods also requires careful selection of the anatomic site for entry of a “free bullet” or “bolt” in the case of penetrating captive bolt. Disease eradication plans for animal health emergencies necessitate methods of euthanasia that will facilitate rapid and efficient depopulation of animals while preserving their welfare to the greatest extent possible. A portable pneumatic captive bolt device has been developed and validated as effective for use in mass depopulation scenarios. Finally, while most tend to focus on the technical aspects of euthanasia, it is extremely important that no one forget the human cost for those who may be required to perform the task of euthanasia on a regular basis. Symptoms including depression, grief, sleeplessness and destructive behaviors including alcoholism and drug abuse are not uncommon for those who participate in the euthanasia of animals.

Vitality and wound-age estimation in forensic pathology: review and future prospects

Determining the age of a wound is challenging in forensic pathology, but it can contribute to the reconstruction of crime scenes and lead to arrest of suspects. Forensic scholars have tended to focus on evaluating wound vitality and determining the time elapsed since the wound was sustained. Recent progress in forensic techniques, particularly high-throughput analyses, has enabled evaluation of materials at the cellular and molecular levels, as well as simultaneous assessment of multiple markers. This paper provides an update on wound-age estimation in forensic pathology, summarizes the recent literature, and considers useful additional information provided by each marker. Finally, the future prospects for estimating wound age in forensic practise are discussed with the hope of providing something useful for further study.

Veterinary Forensic Pathology: The Search for Truth

Veterinary forensic pathology is emerging as a distinct discipline, and this special issue is a major step forward in establishing the scientific basis of the discipline. A forensic necropsy uses the same skill set needed for investigations of natural disease, but the analytical framework and purpose of forensic pathology differ significantly. The requirement of legal credibility and all that it entails distinguishes the forensic from routine diagnostic cases. Despite the extraordinary depth and breadth of knowledge afforded by their training, almost 75% of veterinary pathologists report that their training has not adequately prepared them to handle forensic cases. Many veterinary pathologists, however, are interested and willing to develop expertise in the discipline. Lessons learned from tragic examples of wrongful convictions in medical forensic pathology indicate that a solid foundation for the evolving discipline of veterinary forensic pathology requires a commitment to education, training, and certification. The overarching theme of this issue is that the forensic necropsy is just one aspect in the investigation of a case of suspected animal abuse or neglect. As veterinary pathologists, we must be aware of the roles filled by other veterinary forensic experts involved in these cases and how our findings are an integral part of an investigation. We hope that the outcome of this special issue of the journal is that veterinary pathologists begin to familiarize themselves with not only forensic pathology but also all aspects of veterinary forensic science.

Application of FTIR spectroscopy for traumatic axonal injury: a possible tool for estimating injury interval

Traumatic axonal injury (TAI) is a progressive and secondary injury following traumatic brain injury (TBI). Despite extensive investigations in the field of forensic science and neurology, no effective methods are available to estimate TAI interval between injury and death. In the present study, Fourier transform IR (FTIR) spectroscopy with IR microscopy was applied to collect IR spectra in the corpus callosum (CC) of rats subjected to TAI at 12, 24, and 72 h post-injury compared with control animals. The classification amongst different groups was visualized based on the acquired dataset using hierarchical cluster analysis (HCA) and partial least square (PLS). Furthermore, the established PLS models were used to predict injury interval of TAI in the unknown sample dataset. The results showed that samples at different time points post-injury were distinguishable from each other, and biochemical changes in protein, lipid, and carbohydrate contributed to the differences. Then, the established PLS models provided a satisfactory prediction of injury periods between different sample groups in the external validation. The present study demonstrated the great potential of FTIR-based PLS algorithm as an objective tool for estimating injury intervals of TAI in the field of forensic science and neurology.