Systematic Review of the Prognosis After Mild Traumatic Brain Injury in Adults: Cognitive, Psychiatric, and Mortality Outcomes: Results of the International Collaboration on Mild Traumatic Brain Injury Prognosis

A systematic literature review of psychotherapeutic treatment of prolonged symptoms after mild traumatic brain injury

BACKGROUND

Mild traumatic brain injuries (mTBI) are the most common of traumatic brain injuries and patients often experience a wide range of symptoms such as headache, fatigue, dizziness, sleep problems and subjective cognitive deficits. While most symptomatic patients recover quickly, a sub-group of ~ 10-20% of patients experience prolonged symptoms. There is currently a lack of evidence-based treatment for these patients.

OBJECTIVE

The objective of the present paper was to conduct a systematic review of the literature on psychotherapeutic interventions specifically for patients with prolonged symptoms (> 3 months after injury) after mTBI.

METHODS

With a more precise definition of psychotherapy than previous reviews, an extensive literature search was conducted that yielded 2332 hits, of which five were considered to meet the criteria. Only two of the studies were randomized controlled trials.

RESULTS AND CONCLUSIONS

Results revealed several methodological limitations in the included studies, leading to the conclusion that it is premature to make any strong recommendations on psychotherapeutic treatment of prolonged symptoms after mTBI. With in-depth methodological analyses of the included studies and comprehensive recommendations for future research, the present review aims to inform clinicians and to encourage scientists to engage in collaborative effort towards increasing the number of methodologically sound clinical trials in the field.

Neuropsychological alterations and neuroradiological findings in patients with post-traumatic concussion: Results of a pilot study

INTRODUCTION

Mild traumatic brain injury (mTBI) has traditionally been considered to cause no significant brain damage since symptoms spontaneously remit after a few days. However, this idea is facing increasing scrutiny. The purpose of this study is to demonstrate the presence of early cognitive alterations in a series of patients with mTBI and to link these findings to different markers of brain damage.

METHODS

We conducted a prospective study of a consecutive series of patients with mTBI who were evaluated over a 12-month period. Forty-one (3.7%) of the 1144 included patients had experienced a concussion. Patients underwent a routine clinical evaluation and a brain computed tomography (CT) scan, and were also administered a standardised test for post-concussion symptoms within the first 24hours of mTBI and also 1 to 2 weeks later. The second assessment also included a neuropsychological test battery. The results of these studies were compared to those of a control group of 28 healthy volunteers with similar characteristics. Twenty patients underwent an MRI scan.

RESULTS

Verbal memory and learning were the cognitive functions most affected by mTBI. Seven out of the 20 patients with normal CT findings displayed structural alterations on MR images, which were compatible with diffuse axonal injury in 2 cases.

CONCLUSIONS

Results from this pilot study suggest that early cognitive alterations and structural brain lesions affect a considerable percentage of patients with post-concussion syndrome following mTBI.

MR Imaging Applications in Mild Traumatic Brain Injury: An Imaging Update

Mild traumatic brain injury (mTBI), also commonly referred to as concussion, affects millions of Americans annually. Although computed tomography is the first-line imaging technique for all traumatic brain injury, it is incapable of providing long-term prognostic information in mTBI. In the past decade, the amount of research related to magnetic resonance (MR) imaging of mTBI has grown exponentially, partly due to development of novel analytical methods, which are applied to a variety of MR techniques. Here, evidence of subtle brain changes in mTBI as revealed by these techniques, which are not demonstrable by conventional imaging, will be reviewed. These changes can be considered in three main categories of brain structure, function, and metabolism. Macrostructural and microstructural changes have been revealed with three-dimensional MR imaging, susceptibility-weighted imaging, diffusion-weighted imaging, and higher order diffusion imaging. Functional abnormalities have been described with both task-mediated and resting-state blood oxygen level-dependent functional MR imaging. Metabolic changes suggesting neuronal injury have been demonstrated with MR spectroscopy. These findings improve understanding of the true impact of mTBI and its pathogenesis. Further investigation may eventually lead to improved diagnosis, prognosis, and management of this common and costly condition. (©) RSNA, 2016.

Prevalence of and Risk Factors for Anxiety and Depressive Disorders after Traumatic Brain Injury: A Systematic Review

This review examined pre- and post-injury prevalence of, and risk factors for, anxiety disorders and depressive disorders after traumatic brain injury (TBI), based on evidence from structured diagnostic interviews. A systematic literature search was conducted in EMBASE, MEDLINE, Cochrane Central, PubMed, PsycINFO, and Google Scholar. We identified studies in civilian adults with TBI reporting on the prevalence of anxiety and depressive disorders using structured diagnostic interviews and assessed their quality. Pooled pre- and post-injury prevalence estimates of anxiety disorders and depressive disorders were computed. A total of 34 studies described in 68 publications were identified, often assessing anxiety disorders (n = 9), depressive disorders (n = 7), or a combination of disorders (n = 6). Prevalence rates of psychiatric disorders varied widely. Pooled prevalence estimates of anxiety and depressive disorders were 19% and 13% before TBI and 21% and 17% in the first year after TBI. Pooled prevalence estimates increased over time and indicated high long-term prevalence of Axis I disorders (54%), including anxiety disorders (36%) or depressive disorders (43%). Females, those without employment, and those with a psychiatric history before TBI were at higher risk for anxiety and depressive disorders after TBI. We conclude that a substantial number of patients encounter anxiety and depressive disorders after TBI, and that these problems persist over time. All health care settings should pay attention to the occurrence of psychiatric symptoms in the aftermath of TBI to enable early identification and treatment of these disorders and to enhance the recovery and quality of life of TBI survivors.

Lipid peroxidation and tyrosine nitration in traumatic brain injury: Insights into secondary injury from redox proteomics

Traumatic brain injury (TBI) is a spontaneous event in which sudden trauma and secondary injury cause brain damage. Symptoms of TBI can range from mild to severe depending on extent of injury. The outcome can span from complete patient recovery to permanent memory loss and neurological decline. Currently, there is no known cure for TBI; however, immediate medical attention after injury is most beneficial for patient recovery. It is a well-established concept that imbalances in the production of reactive oxygen species (ROS), reactive nitrogen species (RNS), and native antioxidant mechanisms have been shown to increase oxidative stress. Over the years, proteomics has been used to identify specific biomarkers in diseases such as cancers and neurological disorders such as Alzheimer disease and Parkinson disease. As TBI is a risk factor for a multitude of neurological diseases, biomarkers for this phenomenon are a likely field of study in order to confirm diagnosis. This review highlights the current proteomics studies that investigated excessively nitrated proteins and those altered by lipid peroxidation in TBI. This review also highlights possible diagnostic measures and provides insights for future treatment strategies.

Association between traumatic brain injury and incarceration: a population-based cohort study

BACKGROUND

There is recent evidence to suggest that sustaining a traumatic brain injury (TBI) increases risk of criminal justice system involvement, including incarceration. The objective of this study was to explore the association between TBI and risk of incarceration among men and women in Ontario.

METHODS

We identified a cohort of 1.418 million young adults (aged 18-28 yr) on July 1, 1997, living in Ontario, Canada, from administrative health records; they were followed to Dec. 31, 2011. History of TBI was obtained from emergency and hospital records, and incarceration history was obtained from the Correctional Service of Canada records. We estimated the hazard of incarceration using Cox proportional hazard models, adjusting for relevant sociodemographic characteristics and medical history.

RESULTS

There were 3531 incarcerations over 18 297 508 person-years of follow-up. The incidence of incarceration was higher among participants with prior TBI compared with those without a prior TBI. In fully adjusted models, men and women who had sustained a TBI were about 2.5 times more likely to be incarcerated than men and women who had not sustained a TBI.

INTERPRETATION

Traumatic brain injury was associated with an increased risk of incarceration among men and women in Ontario. Our research highlights the importance of designing primary, secondary and tertiary prevention strategies to mitigate risk of TBI and incarceration in the population.

Postconcussion symptoms reported by Operation Enduring Freedom/Operation Iraqi Freedom veterans with and without blast exposure, mild traumatic brain injury, and posttraumatic stress disorder

OBJECTIVE

This study examined symptom reporting related to the 10th Edition of the International Statistical Classification of Diseases and Related Health Problems (ICD-10) criteria for postconcussional syndrome (PCS) in Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF) Veterans. Our aims were to: (a) examine relationships among PCS symptoms by identifying potential subscales of the British Columbia Postconcussion Symptom Inventory (BC-PSI); and (b) examine group differences in BC-PSI items and subscales in Veterans with and without blast exposure, mild traumatic brain injury (mTBI), and posttraumatic stress disorder (PTSD).

METHOD

Our sample included Veterans with blast-related mTBI history (n = 47), with blast exposure but no mTBI history (n = 20), and without blast exposure (n = 23). Overall, 37 Veterans had PTSD, and 53 did not. We conducted an exploratory factor analysis (EFA) of the BC-PSI followed by multivariate analysis of variance to examine differences in BC-PSI subscale scores by blast exposure, mTBI history, and PTSD.

RESULTS

BC-PSI factors were interpreted as cognitive, vestibular, affective, anger, and somatic. Items and factor scores were highest for Veterans with blast exposure plus mTBI, and lowest for controls. Vestibular, affective, and somatic factors were significantly higher for Veterans with blast exposure plus mTBI than for controls, but not significantly different for those with blast exposure but no mTBI. These results remained significant when PTSD symptom severity was included as a covariate. Cognitive, anger, and somatic subscales were significantly higher for Veterans with PTSD, though there was no interaction effect of PTSD and mTBI or blast history.

CONCLUSIONS

EFA-derived subscales of the BC-PSI differentiated Veterans based on blast exposure, mTBI history, and PTSD.

The potential for animal models to provide insight into mild traumatic brain injury: Translational challenges and strategies

Mild traumatic brain injury (mTBI) is a common health problem. There is tremendous variability and heterogeneity in human mTBI, including mechanisms of injury, biomechanical forces, injury severity, spatial and temporal pathophysiology, genetic factors, pre-injury vulnerability and resilience factors, and clinical outcomes. Animal models greatly reduce this variability and heterogeneity, and provide a means to study mTBI in a rigorous, controlled, and efficient manner. Rodent models, in particular, are time- and cost-efficient, and they allow researchers to measure morphological, cellular, molecular, and behavioral variables in a single study. However, inter-species differences in anatomy, morphology, metabolism, neurobiology, and lifespan create translational challenges. Although the term "mild" TBI is used often in the pre-clinical literature, clearly defined criteria for mild, moderate, and severe TBI in animal models have not been agreed upon. In this review, we introduce current issues facing the mTBI field, summarize the available research methodologies and previous studies in mTBI animal models, and discuss how a translational research approach may be useful in advancing our understanding and management of mTBI.

Brain structure alterations and cognitive impairment following repetitive mild head impact: An in vivo MRI and behavioral study in rat

Mild traumatic brain injury (mTBI) or concussion is a common health issue. Several people repeatedly experience head impact milder than that causing concussion. The present study aimed to confirm the effects of such repeated impact on the brain structure and cognitive abilities. Rat models were established by closed skull weight-drop injury. The animals were anesthetized, subjected to single (s)-sham, s-mTBI, repetitive (r)-sham, and r-mTBI, and recovery times were recorded. MRI, including T2-weighted and diffusion tensor imaging (DTI), as well as, neurological severity scores (mNSS) were assessed for the dynamics of the brain structure and neurological function. Morris water maze (MWM) was used to evaluate the cognitive function. The histological examination of r-mTBI rats revealed the basis of structural changes in the brain. There was no significant difference in the recovery time, MRI, mNSS, and MWM between the s-sham and the s-mTBI groups. Compared with r-sham, r-mTBI induced significant differences in the following aspects. The recovery time was prolonged and beam balance test (BBT) in mNSS increased from day 5. MWM performances were worse even after the BBT was recovered. The volumes of the cortex (CT), hippocampus (HP), and lateral ventricle had changed from day 5, which reached a maximum at day 14. Abnormal DTI parameters were observed in CT, corpus callosum, and HP. Histological analyses showed that both in CT and HP, neuron counts reduced at the end of the experiment. Altogether, these findings indicate that non-symptomatic head injury may result in brain atrophy and cognitive impairment when occurred repeatedly.

Early Changes in Cortical Emotion Processing Circuits after Mild Traumatic Brain Injury from Motor Vehicle Collision

Mild traumatic brain injury (mTBI) patients frequently experience emotion dysregulation symptoms, including post-traumatic stress. Although mTBI likely affects cortical activation and structure, resulting in cognitive symptoms after mTBI, early effects of mTBI on cortical emotion processing circuits have rarely been examined. To assess early mTBI effects on cortical functional and structural components of emotion processing, we assessed cortical activation to fearful faces within the first 2 weeks after motor vehicle collision (MVC) in survivors who did and did not experience mTBI. We also examined the thicknesses of cortical regions with altered activation. MVC survivors with mTBI (n = 21) had significantly less activation in left superior parietal gyrus (SPG) (-5.9, -81.8, 33.8; p = 10^-3.623), left medial orbitofrontal gyrus (mOFG) (-4.7, 36.1, -19.3; p = 10^-3.231), and left and right lateral orbitofrontal gyri (lOFG) (left: -16.0, 41.4, -16.6; p = 10^-2.573; right: 18.7, 22.7, -17.7; p = 10^-2.764) than MVC survivors without mTBI (n = 23). SPG activation in mTBI survivors within 2 weeks after MVC was negatively correlated with subsequent post-traumatic stress symptom severity at 3 months (r = -0.68, p = 0.03). Finally, the SPG region was thinner in the mTBI survivors than in the non-mTBI survivors (F = 11.07, p = 0.002). These results suggest that early differences in activation and structure in cortical emotion processing circuits in trauma survivors who sustain mTBI may contribute to the development of emotion-related symptoms.

Chronic impact of traumatic brain injury on outcome and quality of life: a narrative review

Traditionally seen as a sudden, brutal event with short-term impairment, traumatic brain injury (TBI) may cause persistent, sometimes life-long, consequences. While mortality after TBI has been reduced, a high proportion of severe TBI survivors require prolonged rehabilitation and may suffer long-term physical, cognitive, and psychological disorders. Additionally, chronic consequences have been identified not only after severe TBI but also in a proportion of cases previously classified as moderate or mild. This burden affects the daily life of survivors and their families; it also has relevant social and economic costs.

Outcome evaluation is difficult for several reasons: co-existing extra-cranial injuries (spinal cord damage, for instance) may affect independence and quality of life outside the pure TBI effects; scales may not capture subtle, but important, changes; co-operation from patients may be impossible in the most severe cases. Several instruments have been developed for capturing specific aspects, from generic health status to specific cognitive functions. Even simple instruments, however, have demonstrated variable inter-rater agreement.

The possible links between structural traumatic brain damage and functional impairment have been explored both experimentally and in the clinical setting with advanced neuro-imaging techniques. We briefly report on some fundamental findings, which may also offer potential targets for future therapies.

Better understanding of damage mechanisms and new approaches to neuroprotection-restoration may offer better outcomes for the millions of survivors of TBI.

Screening for Post-Traumatic Stress Disorder in a Civilian Emergency Department Population with Traumatic Brain Injury

Post-traumatic stress disorder (PTSD) is a condition associated with traumatic brain injury (TBI). While the importance of PTSD and TBI among military personnel is widely recognized, there is less awareness of PTSD associated with civilian TBI. We examined the incidence and factors associated with PTSD 6 months post-injury in a civilian emergency department population using measures from the National Institute of Neurological Disorders and Stroke TBI Common Data Elements Outcome Battery. Participants with mild TBI (mTBI) from the Transforming Research and Clinical Knowledge in Traumatic Brain Injury Pilot study with complete 6-month outcome batteries (n = 280) were analyzed. Screening for PTSD symptoms was conducted using the PTSD Checklist-Civilian Version. Descriptive measures are summarized and predictors for PTSD were examined using logistic regression. Incidence of screening positive for PTSD was 26.8% at 6 months following mTBI. Screening positive for PTSD was significantly associated with concurrent functional disability, post-concussive and psychiatric symptomatology, decreased satisfaction with life, and decreased performance in visual processing and mental flexibility. Multi-variable regression showed injury mechanism of assault (odds ratio [OR] 3.59; 95% confidence interval [CI] 1.69-7.63; p = 0.001) and prior psychiatric history (OR 2.56; 95% CI 1.42-4.61; p = 0.002) remained significant predictors of screening positive for PTSD, while education (per year OR 0.88; 95% CI 0.79-0.98; p = 0.021) was associated with decreased odds of PTSD. Standardized data collection and review of pre-injury education, psychiatric history, and injury mechanism during initial hospital presentation can aid in identifying patients with mTBI at risk for developing PTSD symptoms who may benefit from closer follow-up after initial injury care.

COMT and ANKK1 Genetics Interact With Depression to Influence Behavior Following Severe TBI: An Initial Assessment

OBJECTIVE

Genetic variations in the dopamine (DA) system are associated with cortical-striatal behavior in multiple populations. This study assessed associations of functional polymorphisms in the ankyrin repeat and kinase domain (ANKK1; Taq1a) and catechol-O-methyltransferase (COMT; Val158Met) genes with behavioral dysfunction following traumatic brain injury (TBI).

PARTICIPANTS

This was a prospective study of 90 survivors of severe TBI recruited from a level 1 trauma center.

MAIN MEASURES

The Frontal Systems Behavior Scale, a self- or family report questionnaire evaluating behavior associated with frontal lobe dysfunction, was completed 6 and 12 months postinjury. Depression was measured concurrently with the Patient Health Questionnaire-9. Study participants were genotyped for Val158Met and Taq1a polymorphisms.

RESULTS

No statistically significant behavioral differences were observed by Taq1a or Val158Met genotype alone. At 12 months, among those with depression, Met homozygotes (Val158Met) self-reported worse behavior than Val carriers (P = .015), and A2 homozygotes (Taq1a) self-reported worse behavior than A1 carriers (P = .028) in bivariable analysis. Multivariable models suggest an interaction between depression and genetic variation with behavior at 12 months post-TBI, and descriptive analysis suggests that carriage of both risk alleles may contribute to worse behavioral performance than carriage of either risk allele alone.

CONCLUSION

In the context of depression, Val158Met and Taq1a polymorphisms are individually associated with behavioral dysfunction 12 months following severe TBI, with preliminary evidence suggesting cumulative, or perhaps epistatic, effects of COMT and ANKK1 on behavioral dysfunction.

Trends in Sports- and Recreation-Related Traumatic Brain Injuries Treated in US Emergency Departments: The National Electronic Injury Surveillance System-All Injury Program (NEISS-AIP) 2001-2012

IMPORTANCE

Sports- and recreation-related traumatic brain injuries (SRR-TBIs) are a growing public health problem affecting persons of all ages in the United States.

OBJECTIVE

To describe the trends of SRR-TBIs treated in US emergency departments (EDs) from 2001 to 2012 and to identify which sports and recreational activities and demographic groups are at higher risk for these injuries.

DESIGN

Data on initial ED visits for an SRR-TBI from the National Electronic Injury Surveillance System-All Injury Program (NEISS-AIP) for 2001-2012 were analyzed.

SETTING

NEISS-AIP data are drawn from a nationally representative sample of hospital-based EDs.

PARTICIPANTS

Cases of TBI were identified from approximately 500,000 annual initial visits for all causes and types of injuries treated in EDs captured by NEISS-AIP.

MAIN OUTCOME MEASURE(S)

Numbers and rates by age group, sex, and year were estimated. Aggregated numbers and percentages by discharge disposition were produced.

RESULTS

Approximately 3.42 million ED visits for an SRR-TBI occurred during 2001-2012. During this period, the rates of SRR-TBIs treated in US EDs significantly increased in both males and females regardless of age (all Ps < .001). For males, significant increases ranged from a low of 45.8% (ages 5-9) to a high of 139.8% (ages 10-14), and for females, from 25.1% (ages 0-4) to 211.5% (ages 15-19) (all Ps < .001). Every year males had about twice the rates of SRR-TBIs than females. Approximately 70% of all SRR-TBIs were reported among persons aged 0 to 19 years. The largest number of SRR-TBIs among males occurred during bicycling, football, and basketball. Among females, the largest number of SRR-TBIs occurred during bicycling, playground activities, and horseback riding. Approximately 89% of males and 91% of females with an SRR-TBI were treated and released from EDs.

CONCLUSION AND RELEVANCE

The rates of ED-treated SRR-TBIs increased during 2001-2012, affecting mainly persons aged 0 to 19 years and males in all age groups. Increases began to appear in 2004 for females and 2006 for males. Activities associated with the largest number of TBIs varied by sex and age. Reasons for the reported increases in ED visits are unknown but may be associated with increased awareness of TBI through increased media exposure and from campaigns, such as the Centers for Disease Control and Prevention's Heads Up. Prevention efforts should be targeted by sports and recreational activity, age, and sex.

Relationships between risky sexual behaviour, dysexecutive problems, and mental health in the years following interdisciplinary TBI rehabilitation

Little is known about the long-term consequences of traumatic brain injury (TBI) regarding risky sexual behaviour. The objectives of the study were (1) to compare risky sexual behaviour in a sample of individuals with TBI having received interdisciplinary rehabilitation with that of healthy controls, and (2) to explore the relationships between risky sexual behaviour, executive functions, and mental health in individuals with TBI. The study group consisted of 42 individuals with TBI with a mean age of 37.9 years (SD = 9.7), 12.8 years of education (SD = 3.3), and 3.3 years post-injury (SD = 4.3). Healthy controls consisted of 47 participants, with a mean age of 37.6 years (SD = 10.7), and 13 years of education (SD = 3). Risky sexual behaviour was measured with the Sexual Risk Survey and executive function with the Dysexecutive Questionnaire. Mental health measures included the Generalised Anxiety Disorder Scale, and the Patient Health Questionnaire for depression. Compared to healthy controls, individuals with TBI reported more dysexecutive and mental health problems, without differences in risky sexual behaviour. In individuals with TBI, risky sexual behaviour was associated with behavioural, cognitive and emotional dysexecutive problems, but not with anxiety or depression. It was concluded that special attention should be given to individuals with TBI showing difficulties in executive functions given their association with risky sexual behaviour.

Word Memory Test Predicts Recovery in Claimants With Work-Related Head Injury

OBJECTIVE

To investigate the predictive validity of the Word Memory Test (WMT), a verbal memory neuropsychological test developed as a performance validity measure to assess memory, effort, and performance consistency.

DESIGN

Cohort study with 1-year follow-up.

SETTING

Workers' compensation rehabilitation facility.

PARTICIPANTS

Participants included workers' compensation claimants with work-related head injury (N=188; mean age, 44y; 161 men [85.6%]).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Outcome measures for determining predictive validity included days to suspension of wage replacement benefits during the 1-year follow-up and work status at discharge in claimants undergoing rehabilitation. Analysis included multivariable Cox and logistic regression.

RESULTS

Better WMT performance was significantly but weakly correlated with younger age (r=-.30), documented brain abnormality (r=.28), and loss of consciousness at the time of injury (r=.25). Claimants with documented brain abnormalities on diagnostic imaging scans performed better (∼9%) on the WMT than those without brain abnormalities. The WMT predicted days receiving benefits (adjusted hazard ratio, 1.13; 95% confidence interval, 1.04-1.24) and work status outcome at program discharge (adjusted odds ratio, 1.62; 95% confidence interval, 1.13-2.34).

CONCLUSIONS

Our results provide evidence for the predictive validity of the WMT in workers' compensation claimants. Younger claimants and those with more severe brain injuries performed better on the WMT. It may be that financial incentives or other factors related to the compensation claim affected the performance.

Current status of fluid biomarkers in mild traumatic brain injury

Mild traumatic brain injury (mTBI) affects millions of people annually and is difficult to diagnose. Mild injury is insensitive to conventional imaging techniques and diagnoses are often made using subjective criteria such as self-reported symptoms. Many people who sustain a mTBI develop persistent post-concussive symptoms. Athletes and military personnel are at great risk for repeat injury which can result in second impact syndrome or chronic traumatic encephalopathy. An objective and quantifiable measure, such as a serum biomarker, is needed to aid in mTBI diagnosis, prognosis, return to play/duty assessments, and would further elucidate mTBI pathophysiology. The majority of TBI biomarker research focuses on severe TBI with few studies specific to mild injury. Most studies use a hypothesis-driven approach, screening biofluids for markers known to be associated with TBI pathophysiology. This approach has yielded limited success in identifying markers that can be used clinically, additional candidate biomarkers are needed. Innovative and unbiased methods such as proteomics, microRNA arrays, urinary screens, autoantibody identification and phage display would complement more traditional approaches to aid in the discovery of novel mTBI biomarkers.

Mnesic Profiles According to the Size of Pericerebral Hematoma in Patients with Traumatic Brain Injury

OBJECTIVE

The study aims to assess mnesic performances of patients, following a head injury with pericerebral hematoma, according to the size of the hematoma.

METHODS

Cognitive performances of a group of 25 patients with large (≥10 mm) pericerebral hematomas were compared with those of a matched group of 25 patients with small (<10 mm) ones and a matched group of patient with moderate-severe traumatic brain injury with no pericerebral hematoma.

RESULTS

Executive function and information processing speed were not significantly different. Mnesic performances of the large hematomas group were more impaired: cuing effect (63.5 vs. 80% and 83%; p = 0.002; x03B7;2 = 0.183) and total recall (37.5/48 vs. 43.2 and 44.2; p = 0.022; x03B7;2 = 0.65) of the Free and Cued Recall Test.

CONCLUSION

Memory of those in the large hematomas group was impaired with probable storage/consolidation disorders. To identify specific cognitive disorders resulting from large hematomas, it is justified to systematically screen these disorders and to adapt their management.

Recovery from Mild Traumatic Brain Injury in Previously Healthy Adults

This prospective longitudinal study reports recovery from mild traumatic brain injury (MTBI) across multiple domains in a carefully selected consecutive sample of 74 previously healthy adults. The patients with MTBI and 40 orthopedic controls (i.e., ankle injuries) completed assessments at 1, 6, and 12 months after injury. Outcome measures included cognition, post-concussion symptoms, depression, traumatic stress, quality of life, satisfaction with life, resilience, and return to work. Patients with MTBI reported more post-concussion symptoms and fatigue than the controls at the beginning of recovery, but by 6 months after injury, did not differ as a group from nonhead injury trauma controls on cognition, fatigue, or mental health, and by 12 months, their level of post-concussion symptoms and quality of life was similar to that of controls. Almost all (96%) patients with MTBI returned to work/normal activities (RTW) within the follow-up of 1 year. A subgroup of those with MTBIs and controls reported mild post-concussion-like symptoms at 1 year. A large percentage of the subgroup who had persistent symptoms had a modifiable psychological risk factor at 1 month (i.e., depression, traumatic stress, and/or low resilience), and at 6 months, they had greater post-concussion symptoms, fatigue, insomnia, traumatic stress, and depression, and worse quality of life. All of the control subjects who had mild post-concussion-like symptoms at 12 months also had a mental health problem (i.e., depression, traumatic stress, or both). This illustrates the importance of providing evidence-supported treatment and rehabilitation services early in the recovery period.

Recovery of resting brain connectivity ensuing mild traumatic brain injury

Brains reveal amplified plasticity as they recover from an injury. We aimed to define time dependent plasticity changes in patients recovering from mild traumatic brain injury (mTBI). Twenty-five subjects with mild head injury were longitudinally evaluated within 36 h, 3 and 6 months using resting state functional connectivity (RSFC). Region of interest (ROI) based connectivity differences over time within the patient group and in comparison with a healthy control group were analyzed at p < 0.005. We found 33 distinct ROI pairs that revealed significant changes in their connectivity strength with time. Within 3 months, the majority of the ROI pairs had decreased connectivity in mTBI population, which increased and became comparable to healthy controls at 6 months. Within this diffuse decreased connectivity in the first 3 months, there were also few regions with increased connections. This hyper connectivity involved the salience network and default mode network within 36 h, and lingual, inferior frontal and fronto-parietal networks at 3 months. Our findings in a fairly homogenous group of patients with mTBI evaluated during the 6 month window of recovery defines time varying brain connectivity changes as the brain recovers from an injury. A majority of these changes were seen in the frontal and parietal lobes between 3 and 6 months after injury. Hyper connectivity of several networks supported normal recovery in the first 6 months and it remains to be seen in future studies whether this can predict an early and efficient recovery of brain function.

A functional magnetic resonance imaging study of cognitive control and neurosensory deficits in mild traumatic brain injury

Mild traumatic brain injury patients (mTBI) frequently report symptoms of increased distractability and sensory disturbances during mutisensory stimulation. These common post-concussive symptoms could putatively result from dysfunction within the cognitive control network (CCN; top-down) or from unisensory cortex (bottom-up) itself. Functional magnetic resonance imaging (fMRI) and high-resolution structural data were therefore prospectively collected during a multisensory (audio-visual) cognitive control task from 46 mTBI patients within 3 weeks of injury and 46 matched healthy controls (HC), with a subset of participants returning at 4 months. Multisensory stimuli were presented at two frequencies to manipulate cognitive and perceptual load. Patients self-reported more cognitive, emotional, somatic, vestibular and visual symptoms relative to HC, which improved, but did not entirely resolve, over the 4 month follow-up period. There were no group differences in behavior or functional activation during cognitive control (incongruent--congruent trials). In contrast, patients exhibited abnormal activation within different regions of visual cortex that depended on whether attention was focused on auditory or visual information streams. Patients also exhibited increased activation within bilateral inferior parietal lobules during higher cognitive/perceptual loads, suggesting a compensatory mechanism to achieve similar levels of behavioral performance. Functional abnormalities within the visual cortex and inferior parietal lobules were only partially resolved at 4 months post-injury, suggesting that neural abnormalities may take longer to resolve than behavioral measures used in most clinical settings. In summary, current results indicate that abnormalities within unisensory cortex (particularly visual areas) following mTBI, which likely contribute to deficits commonly reported during multisensory stimulation.

Should an increase in cerebral neurochemicals following head kicks in full contact karate influence return to play?

Background:

Cerebral neurochemicals are markers of traumatic brain injury (TBI).

Objectives:

The aim of the study was to determine whether kicks to the head (KTH) in full contact karate significantly increased serum concentrations of protein S-100B, and neurone specific enolase (NSE). Kicks to the body (KTB) were also quantified to asses muscle tissue injury. Muscle damage was assessed by analysis of serum total creatine kinase (CK).

Methods:

Twenty-four full contact karate practitioners were observed and filmed during actual competition and divided into two main groups post event: (1) Kicks to the head and body group (KTH): n = 12; mean ± SD; age, 30.4 ± 6.7 years; height, 1.74 ± 0.1 m; weight, 79.1 ± 2.1 kg; and (2): Kicks to the body group (KTB): n = 12; mean ± SD; age, 28.2 ± 6.5 years; height, 1.75 ± 0.1 m; weight, 79.2 ± 1.7 kg. The KTH group received direct kicks to the head, while group KTB received kicks and punches to the body. Blood samples were taken before and immediately post-combat for analysis of serum S-100B, NSE, CK and cardiac troponin.

Results:

Significant increases in serum concentrations of S-100B (0.12 ± 0.17 vs. 0.37 ± 0.26, µg.L−1) and NSE (11.8 ± 4.1 vs. 20.2 ± 9.1 ng.mL−1) were encountered after combat in the KTH group and CK (123 ± 53 vs. 184 ± 103 U.L−1) in the KTB group (all P <0.05).

Conclusions:

Head kicks in full contact karate cause elevation of neurochemical markers associated with damaged brain tissue. The severity of injury is related to the early post-traumatic release of protein S-100B and NSE. The early kinetics and appearance post injury can reflect intracranial pathology, and suggest S-100B and NSE are extremely sensitive prognostic markers of TBI.

Diagnosis, prognosis, and clinical management of mild traumatic brain injury

Concussion and mild traumatic brain injury (TBI) are interchangeable terms to describe a common disorder with substantial effects on public health. Advances in brain imaging, non-imaging biomarkers, and neuropathology during the past 15 years have required researchers, clinicians, and policy makers to revise their views about mild TBI as a fully reversible insult that can be repeated without consequences. These advances have led to guidelines on management of mild TBI in civilians, military personnel, and athletes, but their widespread dissemination to clinical management in emergency departments and community-based health care is still needed. The absence of unity on the definition of mild TBI, the scarcity of prospective data concerning the long-term effects of repeated mild TBI and subconcussive impacts, and the need to further develop evidence-based interventions to mitigate the long-term sequelae are areas for future research that will improve outcomes, reduce morbidity and costs, and alleviate delayed consequences that have only recently come to light.

Blast injury: impact on brain and internal organs

Blast trauma can kill or injure by multiple different mechanisms, not all of which may be obvious on initial presentation. Patients injured by blast effects should be treated as having multisystem trauma and managed according to Advanced Trauma Life Support guidelines. For the most severely injured patients, damage control resuscitation should be practiced until definitive hemorrhage control has been achieved. Patients with blast injuries may present in mass-casualty episodes that can overwhelm local resources. This article reviews some specific injuries, as well as the importance of mild traumatic brain injury. The importance of rehabilitation is discussed.

Summary of the findings of the International Collaboration on Mild Traumatic Brain Injury Prognosis

In 2004, the WHO Collaborating Centre for Neurotrauma, Prevention, Management and Rehabilitation Task Force published the first large systematic review and best evidence synthesis on the clinical course and prognosis for recovery after MTBI. Ten years later, the International Collaboration on Mild Traumatic Brain Injury Prognosis (ICoMP) formed to update the original WHO Task Force results. This summary review highlights important clinical findings from the full ICoMP results including the current evidence on the course and prognosis of recovery after MTBI in diverse patient populations (e.g., adults, athletes and children) and injury environments (e.g., motor vehicle collisions) as well as on the risk of long-term outcomes after MTBI, such as Parkinson's disease and dementia. Additional clinical areas of interest in MTBI are also discussed including the similarities between MTBI and other traumatic injuries and the risk of Second Impact Syndrome after sport concussion. Clinicians can use this information to help inform patients on the likely course of recovery after MTBI/concussion and guide better decision-making in the care of these patients.

Occupational needs and intervention strategies for military personnel with mild traumatic brain injury and persistent post-concussion symptoms: a review

Mild traumatic brain injury (mTBI), also known as concussion, has been labeled the "signature injury" of the wars in Iraq and Afghanistan. A subset of military personnel with mTBI experience ongoing symptoms well beyond the normal recovery window. While much research has been dedicated to understanding the etiology and severity of the symptoms, very little has assessed how long-term symptoms impact participation in daily life. A scoping study of the occupational science and occupational therapy literature was conducted to ascertain the current state of research on the impact of mTBI on participation in daily life activities, as well as occupational therapy interventions for mTBI. Although the emphasis in this article is on military personnel with mTBI, studies on civilians with mTBI were included in the review as research with military populations is extremely limited. Based on the literature reviewed, the author suggests a role for occupational science research and occupational therapy practice in meeting the occupational needs of military service members with persistent symptoms after mTBI.