Additive effects of mild head trauma, blast exposure, and aging within white matter tracts: A novel Diffusion Tensor Imaging analysis approach.

Existing diffusion tensor imaging (DTI) studies of neurological injury following high-level blast exposure (hlBE) in military personnel have produced widely variable results. This is potentially due to prior studies often not considering the quantity and/or recency of hlBE, as well as co-morbidity with non-blast head trauma (nbHT). Herein, we compare commonly used DTI metrics: fractional anisotropy and mean, axial, and radial diffusivity, in Veterans with and without history of hlBE and/or nbHT. We use both the traditional method of dividing participants into 2 equally weighted groups and an alternative method wherein each participant is weighted by quantity and recency of hlBE and/or nbHT. While no differences were detected using the traditional method, the alternative method revealed diffuse and extensive changes in all DTI metrics. These effects were quantified within 43 anatomically defined white matter tracts, which identified the forceps minor, middle corpus callosum, acoustic and optic radiations, fornix, uncinate, inferior fronto-occipital and inferior longitudinal fasciculi, and cingulum, as the pathways most affected by hlBE and nbHT. Moreover, additive effects of aging were present in many of the same tracts suggesting that these neuroanatomical effects may compound with age.

Impact of repeated blast exposure on active-duty United States Special Operations Forces.

United States (US) Special Operations Forces (SOF) are frequently exposed to explosive blasts in training and combat, but the effects of repeated blast exposure (RBE) on SOF brain health are incompletely understood. Furthermore, there is no diagnostic test to detect brain injury from RBE. As a result, SOF personnel may experience cognitive, physical, and psychological symptoms for which the cause is never identified, and they may return to training or combat during a period of brain vulnerability. In 30 active-duty US SOF, we assessed the relationship between cumulative blast exposure and cognitive performance, psychological health, physical symptoms, blood proteomics, and neuroimaging measures (Connectome structural and diffusion MRI, 7 Tesla functional MRI, [11C]PBR28 translocator protein [TSPO] positron emission tomography [PET]-MRI, and [18F]MK6240 tau PET-MRI), adjusting for age, combat exposure, and blunt head trauma. Higher blast exposure was associated with increased cortical thickness in the left rostral anterior cingulate cortex (rACC), a finding that remained significant after multiple comparison correction. In uncorrected analyses, higher blast exposure was associated with worse health-related quality of life, decreased functional connectivity in the executive control network, decreased TSPO signal in the right rACC, and increased cortical thickness in the right rACC, right insula, and right medial orbitofrontal cortex-nodes of the executive control, salience, and default mode networks. These observations suggest that the rACC may be susceptible to blast overpressure and that a multimodal, network-based diagnostic approach has the potential to detect brain injury associated with RBE in active-duty SOF.

Increased [18F]Fluorodeoxyglucose Uptake in the Left Pallidum in Military Veterans with Blast-Related Mild Traumatic Brain Injury: Potential as an Imaging Biomarker and Mediation with Executive Dysfunction and Cognitive Impairment.

Blast-related mild traumatic brain injury (blast-mTBI) can result in a spectrum of persistent symptoms leading to substantial functional impairment and reduced quality of life. Clinical evaluation and discernment from other conditions common to military service can be challenging and subject to patient recall bias and the limitations of available assessment measures. The need for objective biomarkers to facilitate accurate diagnosis, not just for symptom management and rehabilitation but for prognostication and disability compensation purposes is clear. Toward this end, we compared regional brain [18F]fluorodeoxyglucose-positron emission tomography ([18F]FDG-PET) intensity-scaled uptake measurements and motor, neuropsychological, and behavioral assessments in 79 combat Veterans with retrospectively recalled blast-mTBI with 41 control participants having no lifetime history of TBI. Using an agnostic and unbiased approach, we found significantly increased left pallidum [18F]FDG-uptake in Veterans with blast-mTBI versus control participants, p < 0.0001; q = 3.29 × 10-9 [Cohen's d, 1.38, 95% confidence interval (0.96, 1.79)]. The degree of left pallidum [18F]FDG-uptake correlated with the number of self-reported blast-mTBIs, r2 = 0.22; p < 0.0001. Greater [18F]FDG-uptake in the left pallidum provided excellent discrimination between Veterans with blast-mTBI and controls, with a receiver operator characteristic area under the curve of 0.859 (p < 0.0001) and likelihood ratio of 21.19 (threshold:SUVR ≥ 0.895). Deficits in executive function assessed using the Behavior Rating Inventory of Executive Function-Adult Global Executive Composite T-score were identified in Veterans with blast-mTBI compared with controls, p < 0.0001. Regression-based mediation analyses determined that in Veterans with blast-mTBI, increased [18F]FDG-uptake in the left pallidum-mediated executive function impairments, adjusted causal mediation estimate p = 0.021; total effect estimate, p = 0.039. Measures of working and prospective memory (Auditory Consonant Trigrams test and Memory for Intentions Test, respectively) were negatively correlated with left pallidum [18F]FDG-uptake, p < 0.0001, with mTBI as a covariate. Increased left pallidum [18F]FDG-uptake in Veterans with blast-mTBI compared with controls did not covary with dominant handedness or with motor activity assessed using the Unified Parkinson's Disease Rating Scale. Localized increased [18F]FDG-uptake in the left pallidum may reflect a compensatory response to functional deficits following blast-mTBI. Limited imaging resolution does not allow us to distinguish subregions of the pallidum; however, the significant correlation of our data with behavioral but not motor outcomes suggests involvement of the ventral pallidum, which is known to regulate motivation, behavior, and emotions through basal ganglia-thalamo-cortical circuits. Increased [18F]FDG-uptake in the left pallidum in blast-mTBI versus control participants was consistently identified using two different PET scanners, supporting the generalizability of this finding. Although confirmation of our results by single-subject-to-cohort analyses will be required before clinical deployment, this study provides proof of concept that [18F]FDG-PET bears promise as a readily available noninvasive biomarker for blast-mTBI. Further, our findings support a causative relationship between executive dysfunction and increased [18F]FDG-uptake in the left pallidum.

Injuries in Fatalities of Dismounted Blast: Identification of Four Mechanisms of Head and Spine Injury.

Blast is the most common injury mechanism in conflicts of this century due to the widespread use of explosives, confirmed by recent conflicts such as in Ukraine. Data from conflicts in the last century such as Northern Ireland, the Falklands, and Vietnam up to the present day show that between 16% and 21% of personnel suffered a traumatic brain injury. Typical features of fatal brain injury to those outside of a vehicle (hereafter referred to as dismounted) due to blast include the presence of hemorrhagic brain injury alongside skull fractures rather than isolated penetrating injuries more typical of traditional ballistic head injuries. The heterogeneity of dismounted blast has meant that analysis from databases is limited and therefore a detailed look at the radiological aspects of injury is needed to understand the mechanism and pathology of dismounted blast brain injury. The aim of this study was to identify the head and spinal injuries in fatalities due to dismounted blast. All UK military fatalities from dismounted blast who suffered a head injury from 2007-2013 in the Iraq and Afghanistan conflicts were identified retrospectively. Postmortem computerized tomography images (CTPMs) were interrogated for injuries to the head, neck, and spine. All injuries were documented and classified using a radiology brain injury classification (BIC) tool. Chi-squared (χ2) and Fisher's exact tests were used to investigate correlations between injuries, along with odds ratios for determining the direction of correlation. The correlations were clustered. There were 71 fatalities from dismounted blast with an associated head injury with a CTPM or initial CT available for analysis. The results showed the heterogeneity of injury from dismounted blast but also some potential identifiable injury constellations. These were: intracranial haemorrhage, intracranial deep haemorrhage, spinal injury, and facial injury. These identified injury patterns can now be investigated to consider injury mechanisms and so develop mitigation strategies or clinical treatments. Level of Evidence: Observational. Study type: cohort observational.

The relationship between blast-related mild traumatic brain injury and executive function is moderated by white matter integrity.

Blast-related mild traumatic brain injury (BR mTBI) is a critical research area in recent combat veterans due to increased prevalence of survived blasts. Post-BR mTBI outcomes are highly heterogeneous and defining neurological differences may help in discrimination and prediction of cognitive outcomes. This study investigates whether white matter integrity, measured with diffusion tensor imaging (DTI), could influence how remote BR mTBI history is associated with executive control. The sample included 151 Veterans from the Minneapolis Veterans Affairs Medical Center who were administered a clinical/TBI assessment, neuropsychological battery, and DTI scan as part of a larger battery. From previous research, six white matter tracts were identified as having a putative relationship with blast severity: the cingulum, hippocampal cingulum, corticospinal tract, inferior fronto-occipital fasciculus, superior longitudinal fasciculus and uncinate. Fractional anisotropy (FA) of the a priori selected white matter tracts and report of BR mTBI were used as predictors of Trail-Making Test B (TMT-B) performance in a multiple linear regression model. Statistical analysis revealed that FA of the hippocampal cingulum moderated the association between report of at least one BR mTBI and poorer TMT-B performance (p < 0.008), such that lower FA value was associated with worse TMT-B outcomes in individuals with BR mTBI. No significant moderation existed for other selected tracts, and the effect was not observed with predictors aside from history of BR mTBI. Investigation at the individual-tract level may lead to a deeper understanding of neurological differences between blast-related and non-blast related injuries.

Persistent MRI Findings Unique to Blast and Repetitive Mild TBI: Analysis of the CENC/LIMBIC Cohort Injury Characteristics.

INTRODUCTION: MRI represents one of the clinical tools at the forefront of research efforts aimed at identifying diagnostic and prognostic biomarkers following traumatic brain injury (TBI). Both volumetric and diffusion MRI findings in mild TBI (mTBI) are mixed, making the findings difficult to interpret. As such, additional research is needed to continue to elucidate the relationship between the clinical features of mTBI and quantitative MRI measurements. MATERIAL AND METHODS: Volumetric and diffusion imaging data in a sample of 976 veterans and service members from the Chronic Effects of Neurotrauma Consortium and now the Long-Term Impact of Military-Relevant Brain Injury Consortium observational study of the late effects of mTBI in combat with and without a history of mTBI were examined. A series of regression models with link functions appropriate for the model outcome were used to evaluate the relationships among imaging measures and clinical features of mTBI. Each model included acquisition site, participant sex, and age as covariates. Separate regression models were fit for each region of interest where said region was a predictor. RESULTS: After controlling for multiple comparisons, no significant main effect was noted for comparisons between veterans and service members with and without a history of mTBI. However, blast-related mTBI were associated with volumetric reductions of several subregions of the corpus callosum compared to non-blast-related mTBI. Several volumetric (i.e., hippocampal subfields, etc.) and diffusion (i.e., corona radiata, superior longitudinal fasciculus, etc.) MRI findings were noted to be associated with an increased number of repetitive mTBIs versus. CONCLUSIONS: In deployment-related mTBI, significant findings in this cohort were only observed when considering mTBI sub-groups (blast mechanism and total number/dose). Simply comparing healthy controls and those with a positive mTBI history is likely an oversimplification that may lead to non-significant findings, even in consortium analyses.

Imaging findings of the injured in the massive Beirut blast.

PURPOSE: (1) Describe imaging utilization and findings within two weeks of the 2020 Beirut blast according to the mechanism of injury, (2) determine the appropriate imaging modality per organ/system, and (3) describe changes in the workflow of a radiology department to deal with massive crises. MATERIALS AND METHODS: Two hundred sixty patients presented to the largest emergency department in Beirut and underwent imaging within 2 weeks of the blast. In this retrospective study, patients were divided into early (1) and late (2) imaging groups. Patients' demographic, outcome, type and time of imaging studies, body parts imaged, and mechanism and types of injuries were documented. RESULTS: Two hundred five patients in group 1 underwent 502 and 55 patients in group 2 underwent 145 imaging studies. Tertiary blast injuries from direct impact and falling objects were the most common type of injuries followed by secondary (shrapnel) injuries. Both types of injuries affected mostly the head and neck and upper extremities. Plain radiographs were adequate for the extremities and CT for the head and neck. A regularly updated and practiced emergency plan is essential to mobilize staff and equipment and efficiently deliver radiology services during crises. CONCLUSION: Because the powerful Beirut blast occurred at the port located in the periphery of the city, most injuries seen on imaging were of the upper extremities and head and neck caused by the severe blast wind or penetrating shrapnel and resulted from people using their arms to protect their heads and bodies from direct impact and falling objects.

Blast Lung Injury in Children: Injury Patterns and Associated Organ Injuries.

BACKGROUND: Bombings are the most common cause of civilian deaths in wars, and unfortunately, a large proportion of civilian victims are children. OBJECTIVE: This study aimed to evaluate the frequency of blast lung injury (BLI), to evaluate lung injury patterns on tomographic images, and to document the relationship between blast lung and mortality in children exposed to the blast effect. METHODS: Thirty-six children (25.3% of pediatric patients brought to our hospital with blast injury) with BLI were included in the study. The pediatric trauma score evaluations made in the emergency department in the first admission were recorded. Lung injury findings in the computed tomography images of the patients were examined, and injuries detected in other systems were recorded. RESULTS: The most common lung injury pattern was contusion (right: 69.4%, left: 80.6%). The incidence of brain damage (52.4%) and intra-abdominal injury (76.2%) in children with low pediatric trauma score value was statistically significantly higher ( P = 0.049, P = 0.017, respectively). There was no statistically significant correlation between the presence of lung injury, injury patterns, and mortality. The incidence of brain damage in deceased patients (61.5%) was statistically significantly higher than the incidence of brain damage in surviving patients (26.1%) ( P = 0.036). Low pediatric trauma score was observed in 11 (84.6%) of the deceased children and in 10 (43.5%) of the survivors ( P = 0.016). The mean age of children with hemothorax in the right lung was statistically significantly lower than those without ( P = 0.014). CONCLUSION: Our findings revealed that pediatric BLI is common after a blast, that it is associated with other system injuries, and that a multimodal radiological approach is required in child victims.

Early Brain Amyloid Accumulation at PET in Military Instructors Exposed to Subconcussive Blast Injuries.

Background Traumatic brain injury (TBI) is the leading cause of disability in young adults. Recurrent TBI is associated with a range of neurologic sequelae, but the contributing factors behind the development of such chronic encephalopathy are poorly understood. Purpose To quantify early amyloid ß deposition in the brain of otherwise healthy adult men exposed to repeated subconcussive blast injury using amyloid PET. Materials and Methods In this prospective study from January 2020 to December 2021, military instructors who were routinely exposed to repeated blast events were evaluated at two different points: baseline (before blast exposure from breacher or grenade) and approximately 5 months after baseline (after blast exposure). Age-matched healthy control participants not exposed to blasts and without a history of brain injury were evaluated at similar two points. Neurocognitive evaluation was performed with standard neuropsychologic testing in both groups. Analysis of PET data consisted of standardized uptake value measurements in six relevant brain regions and a whole-brain voxel-based statistical approach. Results Participants were men (nine control participants [median age, 33 years; IQR, 32-36 years] and nine blast-exposed participants [median age, 33 years; IQR, 30-34 years]; P = .82). In the blast-exposed participants, four brain regions showed significantly increased amyloid deposition after blast exposure: inferomedial frontal lobe (P = .004), precuneus (P = .02), anterior cingulum (P = .002), and superior parietal lobule (P = .003). No amyloid deposition was observed in the control participants. Discriminant analysis on the basis of regional changes of amyloid accumulation correctly classified the nine healthy control participants as healthy control participants (100%), and seven of the nine blast-exposed participants (78%) were correctly classified as blast exposed. Based on the voxel-based analysis, whole-brain parametric maps of early abnormal early amyloid uptake were obtained. Conclusion Early brain amyloid accumulation was identified and quantified at PET in otherwise healthy adult men exposed to repetitive subconcussive traumatic events. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Haller in this issue.

Secondary blast injury: radiological characteristics of shrapnel injuries in children.

PURPOSE: The aim of this study is to examine the radiological images of child victims suffering from secondary blast injuries, to reveal organ-based injury patterns and their interrelationships, and to record mortality rates that may develop due to injured systems. METHODS: A total of 65 patients with secondary blast injury due to bomb explosion were included in the study. Injury findings due to shrapnel in radiologic images of the patients were examined. Injured systems and types of injuries were recorded. RESULTS: The most common injuries were intra-abdominal injuries (63%) and fractures (58.5%). Lung injury was observed in 4 (9.8%) of 41 patients with intra-abdominal injury, while 37 (90.2%) did not, and this was statistically significant (p = 0.003). The most common intra-abdominal organ injury was a small bowel injury in 23 (35.4%) patients. The coexistence of small bowel injury and large bowel injury was present in 8 patients (34.8%), and it was statistically significant (p = 0.019). A total of 14 (21.5%) of the patients died. There was no significant relationship between mortality and gender (p = 319). Brain damage was present in 10 (71.4%) of the 14 (21.5%) patients who died, which was statistically significant (p < 0.001). CONCLUSION: Our results showed that the most common injuries were intra-abdominal injuries, damage to different organs could occur at the same time, and deaths were especially associated with brain injuries. For this reason, it should not be forgotten that CT scans will have an important place in the triage of the patient, especially in victims with shrapnel at the abdominal and cranial levels in radiography examinations.

Injuries in Underbody Blast Fatalities: Identification of Five Distinct Mechanisms of Head Injury.

Previous research has shown that injuries to the head and neck were prevalent in 73% of all mounted fatalities of underbody blast. The mechanisms that cause such injuries to the central nervous system (CNS) are not yet known. The aim of this study was to identify the head and spinal injuries in fatalities due to underbody blast (UBB) and then develop hypotheses on the causative mechanisms. All U.K. military fatalities from UBB with an associated head injury that occurred during 2007-2013 in the Iraq and Afghanistan conflicts were identified retrospectively. Computed tomography post-mortems (CTPMs) were interrogated for injuries to the head, neck, and spine. All injuries were documented and classified using a radiology classification. Pearson's chi-square and Fisher's exact tests were used to show a relationship between variables and form a hypothesis for injury mechanisms. There were 50 fatalities from UBB with an associated head injury. Of these, 46 had complete CTPMs available for analysis. Chi-square and Fisher's exact tests showed a relationship between lateral ventricle blood and injuries to the abdomen and thorax. Five partially overlapping injury constellations were identified: 1.multiple-level spinal injury with skull fracture and brainstem injury, 2.peri-mesencephalic hemorrhage, 3.spinal and brainstem injury, 4.parenchymal contusions with injury to C0-C1, and 5.an "eggshell" pattern of fractures from direct impact. These injury constellations can now be used to propose injury mechanisms to develop mitigation strategies or clinical treatments.

Incidental blast injuries to the hands of hunters in suburban Africa.

Background: Civilian blast injuries are common during celebrations and festivities. In the intervening times, civilian nonterrorist blast events are rare. The aim of this report is to highlight the increasing occurrence of blast injuries to the dominant right hand of hunters and the ensuing crippling consequences. Methodology: A review of incidental blast injuries to the hand among hunters was conducted. The case files, clinical photographs, and radiographs of consecutive cases of blast injuries presenting to our unit over 3½ years were studied. Result: Six patients had incidental blast injuries to the hand within the period. All the patients were males and hunters by profession. The age range was 30-49 years. The dominant right hand was involved in all the six cases with high-energy soft tissue and bony injuries. Five patients had staged soft tissue coverage while the sixth patient, after initial resuscitation, discharged against medical advice due to economic constraints. Multiple joint stiffness and significant disability occurred in all the affected hands. None of the patients represented for secondary procedures. Conclusion: Incidental blast injuries to the hands of local hunters are lifestyle threatening. The dominant right hand is invariably involved with attendant crippling socioeconomic consequences. Meticulous clinical care and methodical operative intervention are primal to hand salvage.

Résumé Contexte: Les blessures civiles dues à des explosions sont fréquentes lors des célébrations et des festivités. Dans l'intervalle, les explosions civiles non terroristes sont rares. sont rares. L'objectif de ce rapport est de mettre en évidence la fréquence croissante des blessures par explosion de la main droite dominante des chasseurs et les conséquences invalidantes qui en découlent. conséquences invalidantes. Méthodologie: Une revue des blessures accidentelles par explosion à la main chez les chasseurs a été menée. Les dossiers, les photographies cliniques Les dossiers, les photographies cliniques et les radiographies des cas consécutifs de blessures par explosion qui se sont présentés à notre unité pendant 3½ ans ont été étudiés. Résultat: Six patients ont eu blessures accidentelles par explosion à la main au cours de cette période. Tous les patients étaient des hommes et des chasseurs de profession. La tranche d'âge était de 30 à 49 ans. La main droite dominante était impliquée dans les six cas avec des lésions osseuses et des tissus mous à haute énergie. Pour cinq patients, la couverture des tissus mous s'est faite par étapes. tandis que le sixième patient, après une réanimation initiale, a quitté l'hôpital contre avis médical en raison de contraintes économiques. Raideur articulaire multiple et un handicap significatif sont apparus dans toutes les mains affectées. Aucun des patients ne s'est représenté pour des procédures secondaires. Conclusion: Les blessures accidentelles dues à l'explosion de Les blessures accidentelles aux mains des chasseurs locaux menacent leur mode de vie. La main droite dominante est invariablement touchée avec des conséquences socio-économiques invalidantes. conséquences socio-économiques. Des soins cliniques méticuleux et une intervention chirurgicale méthodique sont essentiels pour sauver la main. Mots-clés: Poudre noire, blessure par explosion, mains de chasseurs, accidentelle, banlieue.

Imaging in paediatric blast injuries: musculoskeletal injuries in the Syrian Civil War.

AIM: To examine the radiological images of children with musculoskeletal injuries and accompanying organ injuries caused by explosions to determine the differences and frequency of injury types and to emphasise the importance of radiology in war injuries. MATERIALS AND METHODS: Seventy-four children with injuries caused by bomb explosions were included in the study. The paediatric trauma scores evaluated in the emergency department on the first admission were recorded. All radiographs and computed tomography (CT) images were evaluated for musculoskeletal injuries and accompanying organ injuries. RESULTS: The highest incidence of fracture in the primary blast injury (PBI) group was skull fracture in 15 (62.5%) patients (p=0.01) and fractures in the other groups were most common in the lower extremities. Amputation was observed in nine (31%) patients in the PBI group (p=0.003); however, there were no patients with amputations in the secondary blast injury (SBI) group (p=0.002). The frequency of pneumothorax (79.3%) and pulmonary contusion (59.4%) was high in the PBI group (p<0.001 and p=0.004, respectively). Skull fractures were observed in 15 (88.2%) of 17 patients with brain injury (p<0.001), and skull fractures were the most common fracture site accompanying pulmonary trauma. The average paediatric trauma score of individuals exposed to shrapnel was found to be high (p<0.001). CONCLUSION: Because paediatric musculoskeletal injuries vary with the type of blast injury and severe trauma can occur in children due to blast effects, radiologists who triage mass injuries should understand the effects of blast injury patterns and the spectrum of injury.

Thoracoabdominal injuries after a bomb explosion: blast injuries and their clinical effects.

PURPOSE: To report the types and effects of injuries to the thoracoabdominal region caused by blast and emphasize the importance of the early detection of primary blast injuries. METHODS: Of the 98 patients injured as a result of a bomb explosion, 31 with thoracoabdominal injuries were included in the study. The demographic and laboratory data, operations performed, and radiological findings were obtained from the electronic records of the patients. The injuries caused by the explosion were divided into four categories as primary, secondary, tertiary, and quaternary. The patients with a new injury severity score (NISS) of ≥ 16 were considered to have critical injuries. RESULTS: While mortality developed in 16 (51.6%) of 31 patients included in the study, 15 (48.4%) were discharged after treatment. The mean ages of the patients in the mortality and survivor groups were 29.6 ± 4.5 and 31.1 ± 10.7 years, respectively (p > 0.005). When the two groups were examined, the rate of hypovolemic shock and NISS score were significantly higher in the mortality group (p = 0.001 and p < 0.001, respectively) and the pH of the patients in the mortality group was more acidic (7.18 ± 0.13 vs. 7.34 ± 0.13, p = 0.002). One patient in the survivor group required surgery after the explosion due to missed primary blast injuries. CONCLUSIONS: To make the best use of resources in terrorist attacks and mass casualties that place a huge burden on health systems, it is important to evaluate patients with the highest index of suspicion for concealed blast injuries in terms of hospitalization and observation. In addition, health systems need to develop a cost-effective strategy considering the possibility of delayed-onset blast injuries.

A rare case of iliopsoas abscess caused by a retained shrapnel from a blast injury.

Iliopsoas abscesses (IPA) are uncommon, with an associated mortality rate of up to 20%. We describe the case of a 55-year-old man war veteran who presented with an unusual cause of IPA secondary to retained foreign body (FB). His initial trauma 30 years before was a result of a blast injury with shrapnel penetration suffered after inadvertently driving over a landmine as an ambulance driver in a conflict region. A CT scan was performed, revealing a 13 mmx8 mm radio-opaque FB within the right psoas at the level of the fifth lumbar vertebra with a surrounding collection. Subsequent open surgical exploration removed two gravel fragments. Given the knowledge of a traumatic blast injury with retained FB and repeated episodes of sepsis, surgical exploration is warranted. To our knowledge, this is the first case of recurrent IPA secondary to a retained FB from a historical trauma.

Correlation of Histomorphometric Changes with Diffusion Tensor Imaging for Evaluation of Blast-Induced Auditory Neurodegeneration in Chinchilla.

In the present study, we have evaluated the blast-induced auditory neurodegeneration in chinchilla by correlating the histomorphometric changes with diffusion tensor imaging. The chinchillas were exposed to single unilateral blast-overpressure (BOP) at ∼172dB peak sound pressure level (SPL) and the pathological changes were compared at 1 week and 1 month after BOP. The functional integrity of the auditory system was assessed by auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAE). The axonal integrity was assessed using diffusion tensor imaging at regions of interests (ROIs) of the central auditory neuraxis (CAN) including the cochlear nucleus (CN), inferior colliculus (IC), and auditory cortex (AC). Post-BOP, cyto-architecture metrics such as viable cells, degenerating neurons, and apoptotic cells were quantified at the CAN ROIs using light microscopic studies using cresyl fast violet, hematoxylin and eosin, and modified Crossmon's trichrome stains. We observed mean ABR threshold shifts of 30- and 10-dB SPL at 1 week and 1 month after BOP, respectively. A similar pattern was observed in DPAOE amplitudes shift. In the CAN ROIs, diffusion tensor imaging studies showed a decreased axial diffusivity in CN 1 month after BOP and a decreased mean diffusivity and radial diffusivity at 1 week after BOP. However, morphometric measures such as decreased viable cells and increased degenerating neurons and apoptotic cells were observed at CN, IC, and AC. Specifically, increased degenerating neurons and reduced viable cells were high on the ipsilateral side when compared with the contralateral side. These results indicate that a single blast significantly damages structural and functional integrity at all levels of CAN ROIs.

Imaging findings in patients after the bomb explosion in Somalia on December 28, 2019.

INTRODUCTION: This study aimed to present the radiological findings of injuries in victims as a result of a suicide bombing in Mogadishu, Somalia. METHODS: Of the 82 injured cases admitted to the emergency department within the first six hours after the explosion, those who were radiologically evaluated were included in this retrospective and descriptive study. To analyze and identify the distribution of primary, secondary, and tertiary injuries, they were classified according to the body areas as head-neck, thorax, abdominopelvic, extremity, and vertebra. RESULTS: The mean age (mean ± SD) of 63 patients included in the study was 28.6 ± 10.2 years. Twenty-four (38.1%) of the injured patients were female and 39 (61.9%) were male. Secondary blast injury was the most common type of injury in the study group with a rate of 39/63 (62%). The total number of bomb fragments was 235, of which 113 (47.8%) were seen in the head and neck region, followed by 86 (36.5%) in the extremities. There were 10 patients (15.9%) with lung injury and 13 (20.6%) with tympanic membrane perforation due to the primary blast mechanism. CONCLUSION: Radiological imaging plays an important role in identifying specific findings and patterns of explosive injuries. Therefore, we consider that patients with stable hemodynamics should be radiologically examined for a fast and accurate diagnosis or treatment.

Point-of-care ultrasound for treatment and triage in austere military environments.

BACKGROUND: Assessment and triage in an austere environment represent a major challenge in casualty care. Modern conflicts involve a significant proportion of multiple wounds, either superficial or penetrating, which complicate clinical evaluation. Furthermore, there is often poor accessibility to computed tomography scans and a limited number of surgical teams. Therefore, ultrasound (US) represents a potentially valuable tool for distinguishing superficial fragments or shrapnels from penetrating trauma requiring immediate damage-control surgery. METHODS: This retrospective observational multicenter study assessed casualties treated for 8 months by five medical teams deployed in Africa and Middle East. Two experts, who were experienced in military emergency medicine but did not take part in the missions, carried out an independent analysis for each case, evaluating the contribution of US to the following five items: triage categorization, diagnosis, clinical severity, prehospital therapeutic choices, and priority to operation room. Consensus was obtained using the Delphi method with three rounds. RESULTS: Of 325 casualties, 189 underwent US examination. The mean injury severity scale score was 25.6, and 76% were wounded by an improvised explosive device. Ultrasound was useful for confirming (23%) or excluding (63%) the suspected diagnosis made in the clinical assessment. It also helped obtain a diagnosis that had not been considered for 3% of casualties and was responsible for a major change in procedure or therapy in 4%. Ultrasound altered the surgical priority in 43% of cases. For 30% of cases, US permitted surgery to be temporarily delayed to prioritize another more urgent casualty. CONCLUSION: Ultrasound is a valuable tool for the management of mass casualties by improving treatment and triage, especially when surgical resources are limited. In some situations, US can also correct a diagnosis or improve prehospital therapeutic choices. Field medical teams should be trained to integrate US into their prehospital protocols. LEVEL OF EVIDENCE: Case series (no criterion standard), level V.

Oesophageal rupture from a pneumatic blast injury: an unusual mechanism of blunt oesophageal trauma.

Oesophageal perforation is a serious condition associated with significant morbidity and mortality. Clinical suspicion of oesophageal injury in patients sustaining neck or torso trauma is essential as early diagnosis and management are associated with better outcomes. Oesophageal perforation resulting from blunt trauma is uncommon, and traumatic oesophageal perforation following blast injury is exceedingly rare. We present two cases of patients developing oesophageal perforation from this rare mechanism, review basic principles of management, and key learning points.