Combat-related traumatic brain injury and its implications to military healthcare

Cannabis use disorder contributes to cognitive dysfunction in Veterans with traumatic brain injury

Background

While emerging evidence supports a link between traumatic brain injury (TBI) and progressive cognitive dysfunction in Veterans, there is insufficient information on the impact of cannabis use disorder (CUD) on long-term cognitive disorders. This study aimed to examine the incidences of cognitive disorders in Veterans with TBI and CUD and to evaluate their relationship.

Methods

This retrospective cohort study used the US Department of Veterans Affairs and Department of Defense administrative data from the Long-term Impact of Military-Relevant Brain Injury Consortium-Chronic Effects of Neurotrauma Consortium Phenotype study. Diagnoses suggesting cognitive disorders after a TBI index date were identified using inpatient and outpatient data from 2003 to 2022. We compared the differential cognitive disorders incidence in Veterans who had the following: (1) no CUD or TBI (control group), (2) CUD only, (3) TBI only, and (4) comorbid CUD+TBI. Kaplan-Meier analyses were used to estimate the overall cognitive disorders incidence in the above study groups. The crude and adjusted Cox proportional hazards models were used to estimate crude and adjusted hazard ratios (HRs) for cognitive disorders.

Results

A total of 1,560,556 Veterans [82.32% male, median (IQR) age at the time of TBI, 34.51 (11.29) years, and 61.35% white] were evaluated. The cognitive disorder incidence rates were estimated as 0.68 (95% CI, 0.62, 0.75) for CUD only and 1.03 (95% CI, 1.00, 1.06) for TBI only per 10,000 person-months of observations, with the highest estimated cognitive disorder incidence observed in participants with both TBI and CUD [1.83 (95% CI, 1.72, 1.95)]. Relative to the control group, the highest hazard of cognitive disorders was observed in Veterans with CUD+TBI [hazard ratio (HR), 3.26; 95% CI, 2.91, 3.65], followed by those with TBI only (2.32; 95 CI%, 2.13, 2.53) and with CUD (1.79; 95 CI%, 1.60, 2.00). Of note, in the CUD only subgroup, we also observed the highest risk of an early onset cognitive disorder other than Alzheimer's disease and Frontotemporal dementia.

Discussion

The results of this analysis suggest that individuals with comorbid TBI and CUD may be at increased risk for early onset cognitive disorders, including dementia.

Cognitive Effects of Astaxanthin Pretreatment on Recovery From Traumatic Brain Injury

Traumatic brain injury (TBI), caused by mechanical impact to the brain, is a leading cause of death and disability among young adults, with slow and often incomplete recovery. Preemptive treatment strategies may increase the injury resilience of high-risk populations such as soldiers and athletes. In this work, the xanthophyll carotenoid Astaxanthin was examined as a potential nutritional preconditioning method in mice (sabra strain) to increase their resilience prior to TBI in a closed head injury (CHI) model. The effect of Astaxanthin pretreatment on heat shock protein (HSP) dynamics and functional outcome after CHI was explored by gavage or free eating (in pellet form) for 2 weeks before CHI. Assessment of neuromotor function by the neurological severity score (NSS) revealed significant improvement in the Astaxanthin gavage-treated group (100 mg/kg, ATX) during recovery compared to the gavage-treated olive oil group (OIL), beginning at 24 h post-CHI and lasting throughout 28 days (p < 0.007). Astaxanthin pretreatment in pellet form produced a smaller improvement in NSS vs. posttreatment at 7 days post-CHI (p < 0.05). Cognitive and behavioral evaluation using the novel object recognition test (ORT) and the Y Maze test revealed an advantage for Astaxanthin administration via free eating vs. standard chow during recovery post-CHI (ORT at 3 days, p < 0.035; improvement in Y Maze score from 2 to 29 days, p < 0.02). HSP profile and anxiety (open field test) were not significantly affected by Astaxanthin. In conclusion, astaxanthin pretreatment may contribute to improved recovery post-TBI in mice and is influenced by the form of administration.

Penetrating Ballistic-Like Brain Injury Leads to MicroRNA Dysregulation, BACE1 Upregulation, and Amyloid Precursor Protein Loss in Lesioned Rat Brain Tissues

Severe traumatic brain injury (TBI) is a risk factor for neurodegenerative diseases. Yet, the molecular events involving dysregulated miRNAs that may be associated with protein degradation in the brain remains elusive. Quantitation of more than 800 miRNAs was conducted using rat ipsilateral coronal brain tissues collected 1, 3, or 7 days after penetrating ballistic-like brain injury (PBBI). As a control for each time-point, Sham-operated animals received craniotomy alone. Microarray and systems biology analysis indicated that the amplitude and complexity of miRNAs affected were greatest 7 day after PBBI. Arrays and Q-PCR inferred that dysregulation of miR-135a, miR-328, miR-29c, and miR-21 were associated with altered levels of beta-site amyloid precursor protein cleaving enzyme 1 (BACE1), PSEN1, PSEN2, and amyloid precursor protein (APP) genes. These events were followed by increased levels of mature BACE1 protein and concomitant loss of full length APP within 3–7 days, then elevation of amyloid beta (Aβ)-40 7 days after PBBI. This study indicates that miRNA arrays, coupled with systems biology, may be used to guide study design prior validation of miRNA dysregulation. Associative analysis of miRNAs, mRNAs, and proteins within a proposed pathway are poised for further validation as biomarkers and therapeutic targets relevant to TBI-induced APP loss and subsequent Aβ peptide generation during neurodegeneration.

Exosomal MicroRNAs in Military Personnel with Mild Traumatic Brain Injury: Preliminary Results from the Chronic Effects of Neurotrauma Consortium Biomarker Discovery Project

Chronic symptoms after mild traumatic brain injury (mTBI) are common among veterans and service members, and represent a significant source of morbidity, with those who sustain multiple mTBIs at greatest risk. Exosomal micro-RNAs (miRNAs), mediators of intercellular communication, may be involved in chronic TBI symptom persistence. Exosomal miRNA (exomiR) was extracted from 153 participants enrolled in the Chronic Effect of Neurotrauma Consortium (CENC) longitudinal study (no TBI, n = 35; ≥ 3 mTBIs (rTBI), n = 45; 1-2 mTBIs, n = 73). Analyses were performed with nCounter^® Human miRNA Expression Panels and Ingenuity Pathway Analysis (IPA) for identification of gene networks associated with TBI. Generalized linear models were used to analyze the predictive value of exomiR dysregulation and remote neurobehavioral symptoms. Compared with controls, there were 17 dysregulated exomiRs in the entire mTBI group and 32 dysregulated exomiRs in the rTBI group. Two miRNAs, hsa-miR-139-5p and hsa-miR-18a-5p, were significantly differentially expressed in the rTBI and 1-2 mTBI groups. IPA analyses showed that these dysregulated exomiRs correlated with pathways of inflammatory regulation, neurological disease, and cell development. Within the rTBI group, exomiRs correlated with gene activity for hub-genes of tumor protein TP53, insulin-like growth factor 1 receptor, and transforming growth factor beta. TBI history and neurobehavioral symptom survey scores negatively and significantly correlated with hsa-miR-103a-3p expression. Participants with remote mTBI have distinct exomiR profiles, which are significantly linked to inflammatory and neuronal repair pathways. These profiles suggest that analysis of exosomal miRNA expression may provide novel insights into the underlying pathobiology of chronic TBI symptom persistence.

Resilience Among Caregivers of Injured Service Members: Finding the Strengths in Caregiving

OBJECTIVE

To examine the relationships between caregiver resilience and a comprehensive set of sociodemographic and health-related quality of life (HRQOL) predictors among both caregivers and injured service members.

DESIGN

Cross-sectional analysis of an observational cohort.

SETTING

Community dwelling.

PARTICIPANTS

Caregivers (n=87) who provide instrumental or emotional support to injured service members (n=73)(N=160).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

The Connor-Davidson Resilience Scale 25-item version.

RESULTS

Higher caregiver resilience scores were related to lower depressive symptom severity, greater health responsibility, physical activity, nutrition, spiritual growth, interpersonal relations, stress management, and problem-solving orientation. A multivariable regression model showed that spiritual growth and aspects of problem-solving orientation were significantly related to resilience.

CONCLUSIONS

Results highlight the relationships between resilience and spirituality, problem-solving orientation, and aspects of HRQOL among caregivers of injured service members. These findings have important implications for caregiver behavioral health programs designed to promote resilience and draw upon caregiver strengths when taking on a caregiver role. Approaches that include a more integrative medicine or strengths-based emphasis may be particularly beneficial when working with families of injured military.

Is balance performance reduced after mild traumatic brain injury?: Interim analysis from chronic effects of neurotrauma consortium (CENC) multi-centre study

OBJECTIVES

Determine if mild traumatic brain injury (mTBI) history is associated with balance disturbances.

SETTING

Chronic Effects of Neurotrauma Consortium (CENC) centres.

PARTICIPANTS

The CENC multi-centre study enrols post-9/11 era Service Members and Veterans with combat exposure. This sample (n = 322) consisted of enrolees completing initial evaluation by September 2016 at the three sites conducting computerized dynamic post-urography (CDP) testing.

DESIGN

Observational study with cross-sectional analyses using structural equation modelling.

MAIN MEASURES

Comprehensive structured interviews were used to diagnose all lifetime mild traumatic brain injuries (mTBIs). The outcome, Sensory Organization Test (SOT), was measured on CDP dual-plate force platform. Other studied variables were measured by structured interviews, record review and questionnaires.

RESULTS

The overall positive/negative mTBI classification did not have a significant effect on the composite equilibrium score. However, the repetitive mTBI classification showed lower scores for participants with ≥ 3 mTBI versus 1-2 lifetime mTBIs. For repetitive mTBI, pain interference acted as a mediator for the indirect effect, and a direct effect was evident on some sensory condition equilibrium scores.

CONCLUSION

These findings show that repeated mTBI, partially mediated by pain, may lead to later balance disturbances among military combatants. Further study of CDP outcomes within this accruing cohort is warranted.

Chronic Effects of Neurotrauma Consortium (CENC) multicentre study interim analysis: Differences between participants with positive versus negative mild TBI histories

OBJECTIVES

Compare characteristics and outcomes of combat-exposed military personnel with positive versus negative mild traumatic brain injury (mTBI) histories.

SETTING

Recruitment was from registration lists and ambulatory clinics at four veterans administration hospitals.

PARTICIPANTS

Consented veterans and service members completing initial evaluation by September 2016 (n = 492).

DESIGN

Observational with cross-sectional analyses.

MAIN MEASURES

Multimodal assessments including structured interviews, record review, questionnaires, neuroendocrine labs and neurocognitive and sensorimotor performance.

RESULTS

In unadjusted comparisons to those absent lifetime mTBI, the mTBI positive group (84%) had greater combat exposure, more potential concussive events, less social support and more comorbidities, including asthma, sleeping problems and post-traumatic stress disorder. They also fared worse on all sensory and pain symptom scores and self-reported functional and global outcomes. They had poorer scores on Wechsler Adult Intelligence Scale-IV coding (processing speed), TMT-B (visual-motor integration and executive function) and two posturography subtests, but were otherwise equal to TBI negative participants on neurocognitive and sensorimotor testing and neuroendocrine levels.

CONCLUSIONS

Although differences in characteristics exist which were not adjusted for, participants with historical mTBI have greater symptomatology and life functioning difficulties compared with non-TBI. Performance measures were less dissimilar between groups. These findings will guide further research within this accruing cohort.

Traumatic Brain Injury, Sleep, and Mental Health: A Longitudinal Study of Air Force Personnel Pre- and Postdeployment to Iraq

OBJECTIVE

We investigated the complex relationships between traumatic brain injury (TBI), sleep, and mental health problems longitudinally among US service members (SMs) pre- and postdeployment to Iraq.

PARTICIPANTS

One hundred sixty-eight SMs enrolled in a 4-week Air Force Basic Combat Convoy Course predeployment.

DESIGN

Self-report data were collected at the beginning and end of training and then at 1, 3, 6, and 12 months postdeployment. Regression analyses were implemented, and participants were categorized into 4 groups based on TBI history for further statistical analysis.

RESULTS

Positive TBI history was associated with greater symptoms of insomnia and posttraumatic stress predeployment and persistence of insomnia symptoms, posttraumatic stress, and depression postdeployment. Positive TBI history and posttraumatic stress served as risk factors for head injury in Iraq, and SMs who reported a head injury during deployment also endorsed greater posttraumatic stress postdeployment than those without head injury. SMs with positive TBI history who also reported a new TBI in Iraq endorsed the greatest sleep and mental health problems across the study period.

CONCLUSIONS

This study provides valuable information regarding temporal relationships between TBI, sleep, and mental health problems among a combat military population. Findings have important implications from both prevention and clinical perspectives.

Early traumatic brain injury screen in 6594 inpatient combat casualties

INTRODUCTION

The purpose of this study was to review the inpatient traumatic brain injury (TBI) screening program at a Role IV regional resource trauma center. TBI has been coined the "signature wound" during current U.S. combat operations. All patients injured in Iraq or Afghanistan who transit through Landstuhl Regional Medical Center (LRMC) undergo an initial TBI screen regardless of anatomic injury. The incidence and factors associated with positive screening for concussion (physical event+alteration of consciousness (AOC)) and TBI diagnoses were examined.

METHODS

A retrospective review of consecutively admitted patients to LRMC who underwent a TBI screen from 5/06 to 7/11 was performed. Patient characteristics, self-reported symptoms, and TBI diagnoses were analyzed.

FINDINGS

Among 43,852 patients screened during the 5-year period, 6594 were admitted, of whom, 6590 received a complete TBI screen. Predominantly male (97.1%), the mean age was 26.7±7.4 yrs. The average GCS and ISS at admission were 13.9±2.8 and 10.1±8.6, respectively. Positively screened patients averaged 1.8 deployments, 69.5% experienced one or more blasts, 16.1% experienced one or more vehicular crashes, with 18.0% reporting a prior head injury. Of the 2805 (42.6%) who screened positive for possible concussion, 2393 (85.3%) were diagnosed with a concussion/TBI during their inpatient stay; the remaining 412 (14.7%) were identified by screening only. Of the screened positive patients, 1953 (69.6%) reported 1 or more current concussion/TBI-related symptoms; of those with symptom(s), 532 (27.2%) reported 5 or more.

CONCLUSIONS

Early screening based on self-report identified a large number of patients admitted directly from the combat zone with possible deployment-related concussion and TBI symptoms. Such screening provides valuable information to guide decisions about early management and return to duty.

LEVEL OF EVIDENCE

Level III, Therapeutic.

Prospective Tracking and Analysis of Traumatic Brain Injury in Veterans and Military Personnel

OBJECTIVE

To describe the ongoing Clinical Tracking Form (CTF) study of the Defense and Veterans Brain Injury Center (DVBIC).

DESIGN

Prospective longitudinal study. Data at baseline and postinjury are collected on participants through interview and questionnaire, review of medical records, and periodic follow-ups throughout their lifetime.

SETTING

A regional DVBIC site located at a Veterans Affairs Medical Center.

PARTICIPANTS

Participants (N=211; age range, 18-75y) were enrolled between January 1, 2005, and December 31, 2012, at a regional DVBIC site.

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURES

Injury information, functioning, and psychological health.

RESULTS

Sixty percent of 211 participants were identified as having severe traumatic brain injuries (TBIs), 14% moderate TBIs, and 26% mild TBIs. Of these 211 participants, 79% sustained closed head injuries, 15% penetrating head injuries, and 6% were not reported. Comparing the severity of TBI in combat versus stateside situations, most of the mild injuries (71%) occurred in combat locations, while most of the severe injuries (62%) occurred in the United States. Among those injured in combat, blast-related TBIs (82%) greatly outnumbered non-blast-related TBIs, regardless of severity.

CONCLUSIONS

The CTF study serves as a significant resource of data to understand the effect and outcomes of TBI in the military population. The lifelong experience of military veterans across the full spectrum of TBI and recovery will be recorded through the CTF, and will translate into more informed clinical decisions and educational efforts to guide future research pathways.

Diagnostic accuracy of Posttraumatic Stress Disorder Checklist in blast-exposed military personnel

Researchers often extrapolate posttraumatic stress disorder (PTSD) status from PTSD Checklist (PCL) data. When doing so, cut points should be based on samples with similar characteristics. This study assessed PCL diagnostic accuracy and postconcussive symptom levels within 106 Iraq/Afghanistan war Veterans and servicemembers with recent blast exposure. Two definitions of PTSD were applied: (1) "strict" Diagnostic and Statistical Manual of Mental Health Disorders (DSM), 4th edition (DSM-IV) criteria and (2) "relaxed" DSM-IV criteria dropping the A2 criterion as per the DSM, 5th edition (DSM-V). Using a structured interview for PTSD, we found moderate agreement with the PCL. Under strict criteria, PTSD prevalence was 16%, PCL cut point was 66 at peak kappa, and mean Rivermead Postconcussion Questionnaire (RPQ) score trended higher for those with PTSD than for those without PTSD (35.5 +/- 11.2 vs 30.5 +/- 10.7, respectively; p = 0.080). Under relaxed criteria, PTSD prevalence was 26.4%, PCL cut point was 58 at peak kappa, and those with PTSD had higher RPQ scores than those without PTSD (36.4 +/- 11.2 vs 29.5 +/- 10.2, respectively; p = 0.003). Participants diagnosed with blast-related mild traumatic brain injury (n = 90) did not differ from those without mild traumatic brain injury (n = 16) in symptom scores. In conclusion, persons with combat-related blast exposure need higher than conventional PCL cut points and those with PTSD have more severe postconcussive-type symptoms than those without PTSD.

Lifetime Prevalence and Factors Associated with Head Injury among Older People in Low and Middle Income Countries: A 10/66 Study

Introduction

Traumatic brain injury (TBI) is a growing public health problem around the world, yet there is little information on the prevalence of head injury in low and middle income countries (LMICs). We utilised data collected by the 10/66 research group to investigate the lifetime prevalence of head injury in defined sites in low and middle income countries, its risk factors and its relationship with disability.

Methods

We analysed data from one-phase cross-sectional surveys of all residents aged 65 years and older (n = 16430) distributed across twelve sites in eight low and middle income countries (China, Cuba, Dominican Republic, India, Venezuela, Mexico, Peru, and Puerto Rico). Self-reported cases of head injury with loss of consciousness were identified during the interview. A sensitivity analysis including data provided by informants of people with dementia was also used to estimate the impact of this information on the estimates. Prevalence ratios (PR) from Poisson regressions were used to identify associated risk factors.

Results

The standardised lifetime prevalence of TBI ranged from 0.3% in China to 14.6% in rural Mexico and Venezuela. Being male (PR: 1.6, 95% CI: 1.29–1.82), younger (PR: 0.95, 95% CI: 0.92–0.99), with lower education (PR 0.91, 95% CI: 0.86–0.96), and having fewer assets (PR 0.92, 95% CI: 0.88–0.96), was associated with a higher prevalence of TBI when pooling estimates across sites.

Discussion

Our analysis revealed that the prevalence of TBI in LMICs is similar to that of developed nations. Considering the growing impact of TBI on health resources in these countries, there is an urgent need for further research.

Profile analyses of the Personality Assessment Inventory following military-related traumatic brain injury

Personality Assessment Inventory (PAI) profiles were examined in 160 U.S. service members (SMs) following mild-severe traumatic brain injury (TBI). Participants who sustained a mild TBI had significantly higher PAI scores than those with moderate-severe TBI on eight of the nine clinical scales examined. A two-step cluster analysis identified four PAI profiles, heuristically labeled "High Distress", "Moderate Distress", "Somatic Distress," and "No Distress". Postconcussive and posttraumatic stress symptom severity was highest for the High Distress group, followed by the Somatic and Moderate Distress groups, and the No Distress group. Profile groups differed in age, ethnicity, rank, and TBI severity. Findings indicate that meaningful patterns of behavioral and personality characteristics can be detected in active duty military SMs following TBI, which may prove useful in selecting the most efficacious rehabilitation strategies.

Minor and repetitive head injury

Traumatic brain injury (TBI) is the leading cause of death and disability in the young, active population and expected to be the third leading cause of death in the whole world until 2020. The disease is frequently referred to as the silent epidemic, and many authors highlight the "unmet medical need" associated with TBI.The term traumatically evoked brain injury covers a heterogeneous group ranging from mild/minor/minimal to severe/non-salvageable damages. Severe TBI has long been recognized to be a major socioeconomical health-care issue as saving young lives and sometimes entirely restituting health with a timely intervention can indeed be extremely cost efficient.Recently it has been recognized that mild or minor TBI should be considered similarly important because of the magnitude of the patient population affected. Other reasons behind this recognition are the association of mild head injury with transient cognitive disturbances as well as long-term sequelae primarily linked to repeat (sport-related) injuries.The incidence of TBI in developed countries can be as high as 2-300/100,000 inhabitants; however, if we consider the injury pyramid, it turns out that severe and moderate TBI represents only 25-30 % of all cases, while the overwhelming majority of TBI cases consists of mild head injury. On top of that, or at the base of the pyramid, are the cases that never show up at the ER - the unreported injuries.Special attention is turned to mild TBI as in recent military conflicts it is recognized as "signature injury."This chapter aims to summarize the most important features of mild and repetitive traumatic brain injury providing definitions, stratifications, and triage options while also focusing on contemporary knowledge gathered by imaging and biomarker research.Mild traumatic brain injury is an enigmatic lesion; the classification, significance, and its consequences are all far less defined and explored than in more severe forms of brain injury.Understanding the pathobiology and pathomechanisms may aid a more targeted approach in triage as well as selection of cases with possible late complications while also identifying the target patient population where preventive measures and therapeutic tools should be applied in an attempt to avoid secondary brain injury and late complications.

Transcranial low-level laser therapy enhances learning, memory, and neuroprogenitor cells after traumatic brain injury in mice

The use of transcranial low-level laser (light) therapy (tLLLT) to treat stroke and traumatic brain injury (TBI) is attracting increasing attention. We previously showed that LLLT using an 810-nm laser 4 h after controlled cortical impact (CCI)-TBI in mice could significantly improve the neurological severity score, decrease lesion volume, and reduce Fluoro-Jade staining for degenerating neurons. We obtained some evidence for neurogenesis in the region of the lesion. We now tested the hypothesis that tLLLT can improve performance on the Morris water maze (MWM, learning, and memory) and increase neurogenesis in the hippocampus and subventricular zone (SVZ) after CCI-TBI in mice. One and (to a greater extent) three daily laser treatments commencing 4-h post-TBI improved neurological performance as measured by wire grip and motion test especially at 3 and 4 weeks post-TBI. Improvements in visible and hidden platform latency and probe tests in MWM were seen at 4 weeks. Caspase-3 expression was lower in the lesion region at 4 days post-TBI. Double-stained BrdU-NeuN (neuroprogenitor cells) was increased in the dentate gyrus and SVZ. Increases in double-cortin (DCX) and TUJ-1 were also seen. Our study results suggest that tLLLT may improve TBI both by reducing cell death in the lesion and by stimulating neurogenesis.

The challenge of mild traumatic brain injury: role of biochemical markers in diagnosis of brain damage

During the past decade there has been an increasing recognition of the incidence of mild traumatic brain injury (mTBI) and a better understanding of the subtle neurological and cognitive deficits that may result from it. A substantial, albeit suboptimal, effort has been made to define diagnostic criteria for mTBI and improve diagnostic accuracy. Thus, biomarkers that can accurately and objectively detect brain injury after mTBI and, ideally, aid in clinical management are needed. In this review, we discuss the current research on serum biomarkers for mTBI including their rationale and diagnostic performances. Sensitive and specific biomarkers reflecting brain injury can provide important information regarding TBI pathophysiology and serve as candidate markers for predicting abnormal computed tomography findings and/or the development of residual deficits in patients who sustain an mTBI. We also outline the roles of biomarkers in settings of specific interest including pediatric TBI, sports concussions and military injuries, and provide perspectives on the validation of such markers for use in the clinic. Finally, emerging proteomics-based strategies for identifying novel markers will be discussed.

Introduction of calpain inhibitors in traumatic brain injury: a novel approach?

Traumatic brain injury (TBI) is a major cause of death and disability throughout the world. In recent years, researchers focused on the pathological significance of calcium accumulation in the brain after TBI. Neuronal calcium homeostasis disturbances may result in the activation of calpain a ubiquitous calcium-sensitive protease. The calpain family has a well-established causal role in neuronal cell death following acute brain injury: their activation has been observed to progressively increase after either contusive or diffuse brain trauma in animals, suggesting calpain to be a mediator of early neuronal damage. We hypothesize that pretreatment with the calpain inhibitors in population at objective risk (military soldiers' pre combat) in appropriate dose would open therapeutic time window expected to prevent and reduce extensive brain damage by providing optimal TBI neuroprotection. Additional therapeutic strategy for TBI, based on calpain modulating actions such as pretreatment with calpain inhibitors has been proposed. Since calpain overexpression has been well established in acute neuronal injury and further subsequent neurodegeneration, from a clinical viewpoint, we speculate that if this hypothesis proves correct pretreatment inhibitors introduction may become a therapeutic option for different brain pathologies to be approached and treated with.

The diagnosis of traumatic brain injury on the battlefield

The conflicts in Iraq and Afghanistan have placed an increased awareness on traumatic brain injury (TBI). Various publications have estimated the incidence of TBI for our deployed servicemen, however all have been based on extrapolations of data sets or subjective evaluations due to our current method of diagnosing a TBI. Therefore it has been difficult to get an accurate rate and severity of deployment related TBIs, or the incidence of multiple TBIs our service members are experiencing. As such, there is a critical need to develop a rapid objective method to diagnose TBI on the battlefield. Because of the austere environment of the combat theater the ideal diagnostic platform faces numerous logistical constraints not encountered in civilian trauma centers. Consequently, a simple blood test to diagnosis TBI represents a viable option for the military. This perspective will provide information on some of the current options for TBI biomarkers, detail concerning battlefield constraints, and a possible acquisition strategy for the military. The end result is a non-invasive TBI diagnostic platform capable of providing much needed advances in objective triage capabilities and improved clinical management of in-Theater TBI.