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Cao Y, Liu Y, Tang L, Jiang Z, Liu Z, Zhou L, Yang B. Quantitative assessment of brain injury and concussion induced by an unintentional soccer ball impact. Injury 2024; 55:111658. [PMID: 38879923 DOI: 10.1016/j.injury.2024.111658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 05/21/2024] [Accepted: 06/03/2024] [Indexed: 06/18/2024]
Abstract
BACKGROUND Accidental impact on a player's head by a powerful soccer ball may lead to brain injuries and concussions during games. It is crucial to assess these injuries promptly and accurately on the field. However, it is challenging for referees, coaches, and even players themselves to accurately recognize potential injuries and concussions following such impacts. Therefore, it is necessary to establish a list of minimum ball velocity thresholds that can result in concussions at different impact locations on the head. Additionally, it is important to identify the affected brain regions responsible for impairments in brain function and potential clinical symptoms. METHODS By using a full human finite element model, dynamic responses and brain injuries caused by unintentional soccer ball impacts on six distinct head locations (forehead, tempus, crown, occiput, face, and jaw) at varying ball velocities (10, 15, 20, 25, 30, 35, 40, and 60 m/s) were simulated and investigated. Intracranial pressure, Von-Mises stress, and first principal strain were analyzed, the ball velocity thresholds resulting in concussions at different impact locations were evaluated, and the damage evolution patterns in the brain tissue were analyzed. RESULTS The impact on the occiput is most susceptible to induce brain injuries compared to all other impact locations. For a conservative assessment, the risk of concussion is present once the soccer ball reaches 17.2 m/s in a frontal impact, 16.6 m/s in a parietal impact, 14.0 m/s in an occipital impact, 17.8 m/s in a temporal impact, 18.5 m/s in a facial impact or 19.2 m/s in a mandibular impact. The brain exhibits the most significant dynamic responses during the initial 10-20 ms, and the damaged regions are primarily concentrated in the medial temporal lobe and the corpus callosum, potentially causing impairments in brain functions. CONCLUSIONS This work offers a framework for quantitatively assessing brain injuries and concussions induced by an unintentional soccer ball impact. Determining the ball velocity thresholds at various impact locations provides a benchmark for evaluating the risks of concussion. The examination of brain tissue damage evolution introduces a novel approach to linking biomechanical responses with possible clinical symptoms.
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Affiliation(s)
- Yangjian Cao
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China
| | - Yiping Liu
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China.
| | - Liqun Tang
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China
| | - Zhenyu Jiang
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China
| | - Zejia Liu
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China
| | - Licheng Zhou
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China
| | - Bao Yang
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China
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Balart-Sánchez SA, Bittencourt M, van der Naalt J, Maurits NM. Lower cognitive reserve is related to worse working memory performance in older adults after mTBI. An ERP study. Brain Inj 2024; 38:550-558. [PMID: 38481123 DOI: 10.1080/02699052.2024.2328307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 03/05/2024] [Indexed: 05/15/2024]
Abstract
OBJECTIVE Older adults (OA) after mild traumatic brain injury (mTBI) have a high risk of developing persistent post-injury cognitive impairments. Lower pre-morbid cognitive reserve (CR) is increasingly investigated as a risk factor for cognitive dysfunction in OA. However, how CR protects against effects of mTBI at the brain level remains largely understudied. METHODS We examined 22 OA who sustained mTBI (mean 67.69 years, SD 5.11) in the sub-acute phase and 15 age- and CR-matched healthy OA (mean 68 years, SD 5.55) performing a three-level visual N-back task using electroencephalography. We calculated inverse efficiency scores of performance from accuracy and reaction times. Event-related potentials served as neurocognitive correlates of attentional (P2) and working memory (P3) processing. RESULTS Overall, mTBI OA performed worse than healthy OA (p = 0.031). Lower CR generally decreased performance (p < 0.001). Furthermore, with increasing task difficulty, task performance was more affected by CR (p = 0.004). At the brain level, P2 amplitude was lower in mTBI OA than in healthy OA (p = 0.05). There was no clear effect of CR on P2 or P3 measures. CONCLUSION As mTBI OA with lower CR performed worse on a working-memory task, lower CR may be a risk factor for worse recovery after mTBI in this group.
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Affiliation(s)
- S A Balart-Sánchez
- Department of Neurology, University of Groningen, University Medical Center Groningen (UMCG), Groningen, The Netherlands
- Research School of Behavioural and Cognitive Neurosciences (BCN), University of Groningen, Groningen, The Netherlands
| | - M Bittencourt
- Department of Neurology, University of Groningen, University Medical Center Groningen (UMCG), Groningen, The Netherlands
- Research School of Behavioural and Cognitive Neurosciences (BCN), University of Groningen, Groningen, The Netherlands
| | - J van der Naalt
- Department of Neurology, University of Groningen, University Medical Center Groningen (UMCG), Groningen, The Netherlands
- Research School of Behavioural and Cognitive Neurosciences (BCN), University of Groningen, Groningen, The Netherlands
| | - N M Maurits
- Department of Neurology, University of Groningen, University Medical Center Groningen (UMCG), Groningen, The Netherlands
- Research School of Behavioural and Cognitive Neurosciences (BCN), University of Groningen, Groningen, The Netherlands
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Abadie A, McKeag I, Springer D, Hale MH, Fernández JR. Differences in Volatile Organic Compounds Between Concussed and Non-concussed Division I Athletes. Cureus 2024; 16:e61241. [PMID: 38939283 PMCID: PMC11210574 DOI: 10.7759/cureus.61241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2024] [Indexed: 06/29/2024] Open
Abstract
Introduction Diagnosing a concussion is challenging because of complex and variable symptoms. Establishing a viable biomarker of injury may rely on physiologic measurements rather than symptomology. Volatile organic compounds (VOCs) such as breath acetone have been identified as potential physiological markers that can capture changes in the utilization of energy substrates post-concussion. Here, we aimed to explore whether differences in VOCs exist between concussed and non-concussed athletes at the initial and later stages of injury recovery. Methods Six (N=6) non-concussed athletes were enrolled as control participants prior to the competitive season. Control participants' breath acetone, heart rate, and anthropometric measures were obtained at rest and throughout a single exercise challenge by breathalyzer. Six (N=6) athletes diagnosed with concussion during the competitive season had breath acetone measured daily until cleared to return to activity or approximately four weeks following enrollment where they participated in an exit exercise challenge having breath acetone, heart rate, and anthropometric measures obtained. Comparisons were made between at-rest measures of concussed and non-concussed participants at multiple time points during the recovery period. Paired t-test comparisons with individuals serving as their own control were used to determine individual differences in recovery. Visual graphs were used to demonstrate differences in obtained measures amongst individuals and between groups during the exercise challenges. Results Results demonstrated statistically significant differences in breath acetone between concussed and control participants when the highest day measured during the first week of concussion was compared to the control participant's resting values (P=0.017). Additionally, when the concussed participants served as their own control and their highest measured day of the first week post-concussion was compared to values when cleared to return to activity or at 26 days post-concussion, there was a significant difference in breath acetone (P=0.028). Comparing breath acetone during exercise between non-concussed and cleared concussed participants or four weeks post-injury, demonstrated no significant differences throughout the challenge or at rest prior. Visual graph comparisons in a single participant before and after concussion suggest differences may appear following exercise during the recovery period. Discussion These results suggest VOCs, particularly breath acetone, have the potential to serve as diagnostic markers of concussion. However, longitudinal research within larger cohorts and with equipment able to expel VOCs other than acetone from measures are needed to make informed recommendations.
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Affiliation(s)
- Allyn Abadie
- Department of Nutrition Sciences, University of Alabama Birmingham, Birmingham, USA
| | - Ian McKeag
- Department of Family and Community Medicine, University of Alabama at Birmingham School of Medicine, Birmingham, USA
| | - Dan Springer
- Department of Athletics, University of Alabama Birmingham, Birmingham, USA
| | - Matthew H Hale
- Department of Family and Community Medicine, University of Alabama at Birmingham School of Medicine, Birmingham, USA
- Department of Athletics, University of Alabama Birmingham, Birmingham, USA
| | - José R Fernández
- Department of Nutrition Sciences, University of Alabama Birmingham, Birmingham, USA
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Janković T, Pilipović K. Single Versus Repetitive Traumatic Brain Injury: Current Knowledge on the Chronic Outcomes, Neuropathology and the Role of TDP-43 Proteinopathy. Exp Neurobiol 2023; 32:195-215. [PMID: 37749924 PMCID: PMC10569144 DOI: 10.5607/en23008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 07/18/2023] [Accepted: 08/23/2023] [Indexed: 09/27/2023] Open
Abstract
Traumatic brain injury (TBI) is one of the most important causes of death and disability in adults and thus an important public health problem. Following TBI, secondary pathophysiological processes develop over time and condition the development of different neurodegenerative entities. Previous studies suggest that neurobehavioral changes occurring after a single TBI are the basis for the development of Alzheimer's disease, while repetitive TBI is considered to be a contributing factor for chronic traumatic encephalopathy development. However, pathophysiological processes that determine the evolvement of a particular chronic entity are still unclear. Human post-mortem studies have found combinations of amyloid, tau, Lewi bodies, and TAR DNA-binding protein 43 (TDP-43) pathologies after both single and repetitive TBI. This review focuses on the pathological changes of TDP-43 after single and repetitive brain traumas. Numerous studies have shown that TDP-43 proteinopathy noticeably occurs after repetitive head trauma. A relatively small number of available preclinical research on single brain injury are not in complete agreement with the results from the human samples, which makes it difficult to draw specific conclusions. Also, as TBI is considered a heterogeneous type of injury, different experimental trauma models and injury intensities may cause differences in the cascade of secondary injury, which should be considered in future studies. Experimental and post-mortem studies of TDP-43 pathobiology should be carried out, preferably in the same laboratories, to determine its involvement in the development of neurodegenerative conditions after one and repetitive TBI, especially in the context of the development of new therapeutic options.
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Affiliation(s)
- Tamara Janković
- Department of Basic and Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Rijeka, Rijeka 51000, Croatia
| | - Kristina Pilipović
- Department of Basic and Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Rijeka, Rijeka 51000, Croatia
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Naumenko Y, Yuryshinetz I, Zabenko Y, Pivneva T. Mild traumatic brain injury as a pathological process. Heliyon 2023; 9:e18342. [PMID: 37519712 PMCID: PMC10372741 DOI: 10.1016/j.heliyon.2023.e18342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 07/10/2023] [Accepted: 07/13/2023] [Indexed: 08/01/2023] Open
Abstract
Traumatic brain injury (TBI) is defined as dysfunction or other evidence of brain pathology caused by external physical force. More than 69 million new cases of TBI are registered worldwide each year, 80% of them - mild TBI. Based on the physical mechanism of induced trauma, we can separate its pathophysiology into primary and secondary injuries. Many literature sources have confirmed that mechanically induced brain injury initiates ionic, metabolic, inflammatory, and neurovascular changes in the CNS, which can lead to acute, subacute, and chronic neurological consequences. Despite the global nature of the disease, its high heterogeneity, lack of a unified classification system, rapid fluctuation of epidemiological trends, and variability of long-term consequences significantly complicate research and the development of new therapeutic strategies. In this review paper, we systematize current knowledge of biomechanical and molecular mechanisms of mild TBI and provide general information on the classification and epidemiology of this complex disorder.
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Affiliation(s)
- Yana Naumenko
- Bogomoletz Institute of Physiology, Department of Sensory Signalization, Kyiv, Ukraine
| | - Irada Yuryshinetz
- Bogomoletz Institute of Physiology, Department of Sensory Signalization, Kyiv, Ukraine
| | - Yelyzaveta Zabenko
- Bogomoletz Institute of Physiology, Department of Sensory Signalization, Kyiv, Ukraine
| | - Tetyana Pivneva
- Bogomoletz Institute of Physiology, Department of Sensory Signalization, Kyiv, Ukraine
- Kyiv Academic University, Kyiv, Ukraine
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White MR, VandeVord PJ. Regional variances depict a unique glial-specific inflammatory response following closed-head injury. Front Cell Neurosci 2023; 17:1076851. [PMID: 36909284 PMCID: PMC9996631 DOI: 10.3389/fncel.2023.1076851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 01/27/2023] [Indexed: 02/17/2023] Open
Abstract
Mild traumatic brain injuries (mTBI) constitute a significant health concern with clinical symptoms ranging from headaches to cognitive deficits. Despite the myriad of symptoms commonly reported following this injury, there is still a lack of knowledge on the various pathophysiological changes that occur. Preclinical studies are at the forefront of discovery delineating the changes that occur within this heterogeneous injury, with the emergence of translational models such as closed-head impact models allowing for further exploration of this injury mechanism. In the current study, male rats were subjected to a closed-head controlled cortical impact (cCCI), producing a concussion (mTBI). The pathological effects of this injury were then evaluated using immunoflourescence seven days following. The results exhibited a unique glial-specific inflammatory response, with both the ipsilateral and contralateral sides of the cortex and hippocampus showing pathological changes following impact. Overall these findings are consistent with glial changes reported following concussions and may contribute to subsequent symptoms.
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Affiliation(s)
- Michelle R White
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States
| | - Pamela J VandeVord
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States.,Salem VA Medical Center, Salem, VA, United States
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Chaychi S, Valera E, Tartaglia MC. Sex and gender differences in mild traumatic brain injury/concussion. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2022; 164:349-375. [PMID: 36038209 DOI: 10.1016/bs.irn.2022.07.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The high incidence of concussions/mild traumatic brain injury and the significant number of people with persisting concussion symptoms as well as the concern for delayed, neurodegenerative effects of concussions makes them a major public health concern. There is much to learn on concussions with respect to pathophysiology as well as vulnerability and resiliency factors. The heterogeneity in outcome after a concussion warrants a more personalized approach to better understand the biological and psychosocial factors that may affect outcome. In this chapter we address biological sex and gender as they impact different aspects of concussion including incidence, risk factors and outcome. As well, this chapter will provide a more fulsome overview of intimate partner violence, an often-overlooked cause of concussion in women. Applying the sex and gender lens to concussion/mild traumatic brain injury is imperative for discovery of its pathophysiology and moving closer to treatments.
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Affiliation(s)
- Samaneh Chaychi
- Memory Clinic, Krembil Brain Institute, University Health Network, Toronto, ON, Canada; Canadian Concussion Centre, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
| | - Eve Valera
- Department of Psychiatry, Harvard Medical School, Boston, MA, United States; Department of Psychiatry, Massachusetts General Hospital, Charlestown, MA, United States
| | - Maria Carmela Tartaglia
- Memory Clinic, Krembil Brain Institute, University Health Network, Toronto, ON, Canada; Canadian Concussion Centre, Krembil Brain Institute, University Health Network, Toronto, ON, Canada; Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada.
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Aderman MJ, Brett BL, Malvasi SR, McGinty G, Jackson JC, Svoboda SJ, McCrea M, Broglio SP, McAllister TW, Pasquina PF, Cameron KL, Houston MN. Association Between Symptom Burden at Initiation of a Graduated Return to Activity Protocol and Time to Return to Unrestricted Activity After Concussion in Service Academy Cadets. Am J Sports Med 2022; 50:823-833. [PMID: 35006034 DOI: 10.1177/03635465211067551] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Current consensus and position statements recommend that concussed patients be asymptomatic upon the initiation of the graduated return to activity (RTA) protocol. However, a significant number of concussed patients are beginning their RTA protocols while endorsing symptoms. PURPOSE To characterize symptom endorsement at the beginning of the RTA protocol and examine the association between symptom endorsement and RTA protocol duration in service academy cadets. STUDY DESIGN Cohort study; Level of evidence, 2. METHODS A prospective cohort study was conducted with cadets at 3 US service academies. Postconcussion symptom inventories were recorded upon the initiation of an RTA protocol. The Sport Concussion Assessment Tool Symptom Inventory was used to classify participants into 3 groups (0 symptoms, 1 symptom, and ≥2 symptoms) upon the initiation of the RTA protocol. The primary outcome of interest was RTA protocol duration. Kaplan-Meier survival estimates were calculated to estimate RTA protocol duration by symptom endorsement, sex, varsity status, academic break, and time to graduated RTA initiation. Univariate and multivariable Cox proportional hazards models were used to estimate the association between symptom endorsement at the initiation of the RTA protocol and RTA protocol duration (α < .05). RESULTS Data were analyzed from 966 concussed cadets (36% women). Headache (42%) and faintness/dizziness (44%) were the most commonly endorsed symptoms on the Sport Concussion Assessment Tool-Third Edition and the Brief Symptom Inventory-18, respectively. Univariate results revealed a significant association between endorsing ≥2 symptoms and RTA protocol duration. In the multivariable model, endorsing ≥2 symptoms maintained a statistically significant association with RTA protocol duration. Significant associations were observed between RTA protocol duration and nonvarsity status (27% longer), women (15% longer), academic breaks (70% longer), and time to the initiation of the RTA protocol (1.1% longer daily incremental increase) after controlling for covariates. CONCLUSION Symptom endorsement at the initiation of an RTA protocol was associated with RTA protocol duration. Cadets who had returned to preinjury baseline symptom burden or improved from baseline symptom burden and endorsed ≥2 symptoms at the initiation of the RTA protocol took longer to RTA.
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Affiliation(s)
| | | | | | - Gerald McGinty
- United States Air Force Academy, Colorado Springs, Colorado, USA
| | | | | | | | - Steven P Broglio
- Michigan Concussion Center, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Paul F Pasquina
- Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Kenneth L Cameron
- Keller Army Hospital, West Point, New York, USA.,Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
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Mira RG, Lira M, Cerpa W. Traumatic Brain Injury: Mechanisms of Glial Response. Front Physiol 2021; 12:740939. [PMID: 34744783 PMCID: PMC8569708 DOI: 10.3389/fphys.2021.740939] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 09/20/2021] [Indexed: 11/17/2022] Open
Abstract
Traumatic brain injury (TBI) is a heterogeneous disorder that involves brain damage due to external forces. TBI is the main factor of death and morbidity in young males with a high incidence worldwide. TBI causes central nervous system (CNS) damage under a variety of mechanisms, including synaptic dysfunction, protein aggregation, mitochondrial dysfunction, oxidative stress, and neuroinflammation. Glial cells comprise most cells in CNS, which are mediators in the brain’s response to TBI. In the CNS are present astrocytes, microglia, oligodendrocytes, and polydendrocytes (NG2 cells). Astrocytes play critical roles in brain’s ion and water homeostasis, energy metabolism, blood-brain barrier, and immune response. In response to TBI, astrocytes change their morphology and protein expression. Microglia are the primary immune cells in the CNS with phagocytic activity. After TBI, microglia also change their morphology and release both pro and anti-inflammatory mediators. Oligodendrocytes are the myelin producers of the CNS, promoting axonal support. TBI causes oligodendrocyte apoptosis, demyelination, and axonal transport disruption. There are also various interactions between these glial cells and neurons in response to TBI that contribute to the pathophysiology of TBI. In this review, we summarize several glial hallmarks relevant for understanding the brain injury and neuronal damage under TBI conditions.
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Affiliation(s)
- Rodrigo G Mira
- Laboratorio de Función y Patología Neuronal, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Matías Lira
- Laboratorio de Función y Patología Neuronal, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Waldo Cerpa
- Laboratorio de Función y Patología Neuronal, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.,Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile
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Aberrant Static and Dynamic Functional Network Connectivity in Acute Mild Traumatic Brain Injury with Cognitive Impairment. Clin Neuroradiol 2021; 32:205-214. [PMID: 34463779 DOI: 10.1007/s00062-021-01082-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 07/31/2021] [Indexed: 10/20/2022]
Abstract
PURPOSE This study aimed to investigate differences in static and dynamic functional network connectivity (FNC) and explore their association with neurocognitive performance in acute mild traumatic brain injury (mTBI). METHODS A total of 76 patients with acute mTBI and 70 age-matched and sex-matched healthy controls were enrolled (age 43.79 ± 10.22 years vs. 45.63 ± 9.49 years; male/female: 34/42 vs. 38/32; all p > 0.05) and underwent resting-state functional magnetic resonance imaging (fMRI) scan (repetition time/echo time = 2000/30 ms, 230 volumes). Independent component analysis was conducted to evaluate static and dynamic FNC patterns on the basis of nine resting-state networks, namely, auditory network (AUDN), dorsal attention network (dAN), ventral attention network (vAN), default mode network (DMN), left frontoparietal network (LFPN), right frontoparietal network (RFPN), somatomotor network (SMN), visual network (VN), and salience network (SN). Spearman's correlation among aberrances in FNC values, and Montreal cognitive assessment (MoCA) scores was further measured in mTBI. RESULTS Compared with controls, patients with mTBI showed wide aberrances of static FNC, such as reduced FNC in DMN-vAN and VN-vAN pairs. The mTBI patients exhibited aberrant dynamic FNC in state 2, involving reduced FNC aberrance in the vAN with AUDN, VN with DMN and dAN, and SN with SMN and vAN. Reduced dFNC in the SN-vAN pair was negatively correlated with the MoCA score. CONCLUSION Our findings suggest that aberrant static and dynamic FNC at the acute stage may contribute to cognitive symptoms, which not only may expand knowledge regarding FNC cognition relations from the static perspective but also from the dynamic perspective.
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Zurlinden T, Savransky A, Everhart DE. Utilizing the BAT-LQ to assess TBI incidence in a college student population. Brain Inj 2021; 35:1229-1234. [PMID: 34436938 DOI: 10.1080/02699052.2021.1972140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
OBJECTIVE Although the annual number of traumatic brain injuries (TBIs) reported in the US exceeds two million, data suggests that this is an underestimate. The goal of this study was to understand lifetime TBI incidence among a sample of college students. Additionally, this study examined whether a single yes/no question regarding TBI history was sufficient to gather accurate information about TBI incidence in college students. DESIGN Participants were asked a single TBI question and administered the BAT-LQ. MAIN MEASURES The BAT-LQ is a screening tool designed to assess for probable lifetime TBIs. RESULTS Data from 121 participants were analyzed for this study. On the single-question, 24.8% of participants reported experiencing a TBI. However, upon further prompting, 76.8% of all participants reported experiencing a blow to the head accompanied by at least one diagnostic symptom of a TBI, suggesting a probable TBI based on best-practice diagnosis guidelines. CONCLUSION The results of this study suggest that increased education about TBI is warranted to ensure that individuals receive care for probable TBIs, as many individuals likely lack knowledge about what constitutes a TBI diagnosis. Additionally, the results suggest that a single question may not be sufficient to capture true lifetime TBI incidence.
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Affiliation(s)
- Taylor Zurlinden
- Department of Psychology, East Carolina University, Rawl Building, Greenville, North Carolina, USA
| | - Anya Savransky
- Department of Psychology, East Carolina University, Rawl Building, Greenville, North Carolina, USA
| | - D Erik Everhart
- Department of Psychology, East Carolina University, Rawl Building, Greenville, North Carolina, USA
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12
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Maintaining Medical Resources to Treat Paediatric Injuries during COVID-19 Lockdown Is Essential-An Epidemiological Analysis of a Level 1 Trauma Centre in Central Europe. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18115829. [PMID: 34071610 PMCID: PMC8198406 DOI: 10.3390/ijerph18115829] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 05/14/2021] [Accepted: 05/26/2021] [Indexed: 11/30/2022]
Abstract
Background: This study examined the effect of the COVID-19 pandemic and the resulting decrease in the incidence of various categories of injuries, with the main focus on fractures and mild traumatic brain injuries in a paediatric population. Methods: This retrospective cohort study evaluated all children from 0 to 18 years of age presenting with an injury at the level 1 trauma centre of the University Clinic of Orthopaedics and Trauma Surgery in Vienna during the lockdown from 16 March to 29 May 2020 compared to records over the same timeframe from 2015 to 2019. Results: In total, 14,707 patients with injuries were included. The lockdown did not lead to a significant decrease in fractures but, instead, yielded a highly significant increase in mild traumatic brain injuries when compared to all injuries that occurred (p = 0.082 and p = 0.0001) as well as acute injuries (excluding contusions, distortions and miscellaneous non-acute injuries) (p = 0.309 and p = 0.034). Conclusions: The percentage of paediatric fractures did not decrease at the level 1 trauma centre, and a highly significant proportional increase in paediatric patients with mild traumatic brain injuries was observed during the COVID-19 lockdown. Therefore, medical resources should be maintained to treat paediatric trauma patients and provide neurological monitoring during pandemic lockdowns.
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A new open-access platform for measuring and sharing mTBI data. Sci Rep 2021; 11:7501. [PMID: 33820939 PMCID: PMC8021549 DOI: 10.1038/s41598-021-87085-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 03/15/2021] [Indexed: 11/08/2022] Open
Abstract
Despite numerous research efforts, the precise mechanisms of concussion have yet to be fully uncovered. Clinical studies on high-risk populations, such as contact sports athletes, have become more common and give insight on the link between impact severity and brain injury risk through the use of wearable sensors and neurological testing. However, as the number of institutions operating these studies grows, there is a growing need for a platform to share these data to facilitate our understanding of concussion mechanisms and aid in the development of suitable diagnostic tools. To that end, this paper puts forth two contributions: (1) a centralized, open-access platform for storing and sharing head impact data, in collaboration with the Federal Interagency Traumatic Brain Injury Research informatics system (FITBIR), and (2) a deep learning impact detection algorithm (MiGNet) to differentiate between true head impacts and false positives for the previously biomechanically validated instrumented mouthguard sensor (MiG2.0), all of which easily interfaces with FITBIR. We report 96% accuracy using MiGNet, based on a neural network model, improving on previous work based on Support Vector Machines achieving 91% accuracy, on an out of sample dataset of high school and collegiate football head impacts. The integrated MiG2.0 and FITBIR system serve as a collaborative research tool to be disseminated across multiple institutions towards creating a standardized dataset for furthering the knowledge of concussion biomechanics.
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14
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Considerations for Pediatric Retirement from Athletics Following Repetitive Concussive Traumatic Brain Injury: Incorporating the Right to an Open Future. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18052266. [PMID: 33668858 PMCID: PMC7956642 DOI: 10.3390/ijerph18052266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 02/19/2021] [Indexed: 11/17/2022]
Abstract
Guidance regarding the decision to remove an adolescent from athletic competition immediately following an acute concussive injury and the safe return of play in the short term is widely accepted and supported by clinical evidence, local institutional policies, and state and federal laws. There is considerably less guidance regarding the decision to permanently retire an adolescent athlete for medical reasons due to concussive injuries. In this article, we discuss the clinical and non-clinical considerations that should guide clinicians in discussions regarding the adolescent athlete’s permanent retirement by emphasizing the ethical obligation to protect the child’s right to an open future as possibly determinative in otherwise ambiguous cases.
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15
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Kratz SV. Case report: Manual therapies promote resolution of persistent post-concussion symptoms in a 24-year-old athlete. SAGE Open Med Case Rep 2021; 9:2050313X20952224. [PMID: 33628444 PMCID: PMC7829464 DOI: 10.1177/2050313x20952224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 07/30/2020] [Indexed: 12/24/2022] Open
Abstract
This case report illustrates the treatment outcomes of a collegiate athlete presenting with an 18-month history of post-concussion syndrome who received a series of mixed manual therapies in isolation of other therapy. Persistent symptoms were self-reported as debilitating, contributing to self-removal from participation in school, work, and leisure activities. Patient and parent interviews captured the history of multiple concussions and other sports-related injuries. Neurological screening and activities of daily living were baseline measured. Post-Concussion Symptom Checklist and Headache Impact Test-6™ were utilized to track symptom severity. Treatments applied included craniosacral therapy, manual lymphatic drainage, and glymphatic techniques. Eleven treatment sessions were administered over 3 months. Results indicated restoration of oxygen saturation, normalized pupil reactivity, and satisfactory sleep. Post-concussion syndrome symptom severity was reduced by 87% as reflected by accumulative Post-Concussion Symptom Checklist scores. Relief from chronic headaches was achieved, reflected by Headache Impact Test-6 scores. Restoration of mood and quality of life were reported. A 6-month follow-up revealed symptoms remained abated with full re-engagement of daily activities. The author hypothesized that post-concussion syndrome symptoms were related to compression of craniosacral system structures and lymphatic fluid stagnation that contributed to head pressure pain, severe sleep deprivation, and multiple neurological and psychological symptoms. Positive outcomes over a relatively short period of time without adverse effects suggest these therapies may offer viable options for the treatment of post-concussion syndrome.
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Affiliation(s)
- Susan Vaughan Kratz
- Registered Occupational Therapist,
CranioSacral Therapy—Diplomat, Special Therapies, Inc., Waukesha, WI,
USA
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16
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Abstract
After a concussion, a series of complex, overlapping, and disruptive events occur within the brain, leading to symptoms and behavioral dysfunction. These events include ionic shifts, damaged neuronal architecture, higher concentrations of inflammatory chemicals, increased excitatory neurotransmitter release, and cerebral blood flow disruptions, leading to a neuronal crisis. This review summarizes the translational aspects of the pathophysiologic cascade of postconcussion events, focusing on the role of excitatory neurotransmitters and ionic fluxes, and their role in neuronal disruption. We review the relationship between physiologic disruption and behavioral alterations, and proposed treatments aimed to restore the balance of disrupted processes.
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Affiliation(s)
- David R Howell
- Sports Medicine Center, Children's Hospital Colorado, 13123 East 16th Avenue, B060, Aurora, CO 80045, USA; Department of Orthopedics, University of Colorado School of Medicine, Aurora, CO, USA.
| | - Julia Southard
- Sports Medicine Center, Children's Hospital Colorado, 13123 East 16th Avenue, B060, Aurora, CO 80045, USA; Department of Psychology and Neuroscience, Regis University, 3333 Regis Boulevard, Denver, CO 80221, USA
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17
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Ellis MJ, Mendez I, Russell K. Preliminary clinical algorithm to optimise remote delivery of paediatric concussion care in Canada's North. Int J Circumpolar Health 2020; 79:1832390. [PMID: 33089768 PMCID: PMC7595137 DOI: 10.1080/22423982.2020.1832390] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Concussion is a form of traumatic brain injury that affects thousands of children and adolescents across Canada annually. With timely access to comprehensive medical care, the majority of patients with acute concussion will recover within 1–4 weeks. Those who develop persistent post-concussion symptoms often benefit from early recognition and referral to multi-disciplinary concussion clinics that have the personnel and resources to meet their complex needs. Youth who live in remote and isolated communities within Canada’s North, a significant proportion of whom are Indigenous, face unique barriers and obstacles to accessing primary and specialised concussion care. Although telemedicine has recently emerged as a tool that can help address these gaps in care, there are presently no clinical guidelines or tools available to assist multi-disciplinary concussion clinics in providing remote concussion care to these medically underserved patients. Here we incorporate literature from a scoping review and our early institutional experience to present an evidence-informed preliminary clinical algorithm and resources to help guide and optimise remote paediatric concussion care delivery in Canada’s North. We also discuss how innovative technologies and partnerships can be leveraged to enhance the delivery of safe, equitable, cost-effective and culturally appropriate care to these communities.
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Affiliation(s)
- Michael J Ellis
- Department of Surgery, University of Manitoba , Winnipeg, MB, Canada.,Department of Pediatrics and Child Health, University of Manitoba , Winnipeg, MB, Canada.,Section of Neurosurgery, University of Manitoba , Winnipeg, MB, Canada.,Pan Am Concussion Program , Winnipeg, MB, Canada.,Childrens Hospital Research Institute of Manitoba , Winnipeg, MB, Canada.,Excellence in Neurodevelopment and Rehabilitation Research in Child Health (ENRRICH) Theme , Winnipeg, MB, Canada
| | - Ivar Mendez
- Department of Surgery, College of Medicine, University of Saskatchewan , Saskatoon, SK, Canada
| | - Kelly Russell
- Department of Pediatrics and Child Health, University of Manitoba , Winnipeg, MB, Canada.,Childrens Hospital Research Institute of Manitoba , Winnipeg, MB, Canada.,Excellence in Neurodevelopment and Rehabilitation Research in Child Health (ENRRICH) Theme , Winnipeg, MB, Canada
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18
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A critical review of radiotracers in the positron emission tomography imaging of traumatic brain injury: FDG, tau, and amyloid imaging in mild traumatic brain injury and chronic traumatic encephalopathy. Eur J Nucl Med Mol Imaging 2020; 48:623-641. [DOI: 10.1007/s00259-020-04926-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 06/11/2020] [Indexed: 12/14/2022]
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19
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McCartney D, Benson MJ, Desbrow B, Irwin C, Suraev A, McGregor IS. Cannabidiol and Sports Performance: a Narrative Review of Relevant Evidence and Recommendations for Future Research. SPORTS MEDICINE - OPEN 2020; 6:27. [PMID: 32632671 PMCID: PMC7338332 DOI: 10.1186/s40798-020-00251-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 05/17/2020] [Indexed: 12/17/2022]
Abstract
Cannabidiol (CBD) is a non-intoxicating cannabinoid derived from Cannabis sativa. CBD initially drew scientific interest due to its anticonvulsant properties but increasing evidence of other therapeutic effects has attracted the attention of additional clinical and non-clinical populations, including athletes. Unlike the intoxicating cannabinoid, Δ9-tetrahydrocannabinol (Δ9-THC), CBD is no longer prohibited by the World Anti-Doping Agency and appears to be safe and well-tolerated in humans. It has also become readily available in many countries with the introduction of over-the-counter "nutraceutical" products. The aim of this narrative review was to explore various physiological and psychological effects of CBD that may be relevant to the sport and/or exercise context and to identify key areas for future research. As direct studies of CBD and sports performance are is currently lacking, evidence for this narrative review was sourced from preclinical studies and a limited number of clinical trials in non-athlete populations. Preclinical studies have observed robust anti-inflammatory, neuroprotective and analgesic effects of CBD in animal models. Preliminary preclinical evidence also suggests that CBD may protect against gastrointestinal damage associated with inflammation and promote healing of traumatic skeletal injuries. However, further research is required to confirm these observations. Early stage clinical studies suggest that CBD may be anxiolytic in "stress-inducing" situations and in individuals with anxiety disorders. While some case reports indicate that CBD improves sleep, robust evidence is currently lacking. Cognitive function and thermoregulation appear to be unaffected by CBD while effects on food intake, metabolic function, cardiovascular function, and infection require further study. CBD may exert a number of physiological, biochemical, and psychological effects with the potential to benefit athletes. However, well controlled, studies in athlete populations are required before definitive conclusions can be reached regarding the utility of CBD in supporting athletic performance.
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Affiliation(s)
- Danielle McCartney
- The University of Sydney, Faculty of Science, School of Psychology, Sydney, New South Wales, 2050, Australia.
- The University of Sydney, Lambert Initiative for Cannabinoid Therapeutics, Sydney, New South Wales, Australia.
- The University of Sydney, Brain and Mind Centre, Sydney, New South Wales, Australia.
| | - Melissa J Benson
- The University of Sydney, Faculty of Science, School of Psychology, Sydney, New South Wales, 2050, Australia
- The University of Sydney, Lambert Initiative for Cannabinoid Therapeutics, Sydney, New South Wales, Australia
- The University of Sydney, Brain and Mind Centre, Sydney, New South Wales, Australia
| | - Ben Desbrow
- School of Allied Health Sciences, Griffith University, Gold Coast, Queensland, Australia
| | - Christopher Irwin
- School of Allied Health Sciences, Griffith University, Gold Coast, Queensland, Australia
- Menzies Health Institute Queensland, Gold Coast, Queensland, Australia
| | - Anastasia Suraev
- The University of Sydney, Faculty of Science, School of Psychology, Sydney, New South Wales, 2050, Australia
- The University of Sydney, Lambert Initiative for Cannabinoid Therapeutics, Sydney, New South Wales, Australia
- The University of Sydney, Brain and Mind Centre, Sydney, New South Wales, Australia
| | - Iain S McGregor
- The University of Sydney, Faculty of Science, School of Psychology, Sydney, New South Wales, 2050, Australia
- The University of Sydney, Lambert Initiative for Cannabinoid Therapeutics, Sydney, New South Wales, Australia
- The University of Sydney, Brain and Mind Centre, Sydney, New South Wales, Australia
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20
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Ichkova A, Rodriguez-Grande B, Zub E, Saudi A, Fournier ML, Aussudre J, Sicard P, Obenaus A, Marchi N, Badaut J. Early cerebrovascular and long-term neurological modifications ensue following juvenile mild traumatic brain injury in male mice. Neurobiol Dis 2020; 141:104952. [PMID: 32442681 DOI: 10.1016/j.nbd.2020.104952] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 05/05/2020] [Accepted: 05/17/2020] [Indexed: 12/15/2022] Open
Abstract
Clinical evidence suggests that a mild traumatic brain injury occurring at a juvenile age (jmTBI) may be sufficient to elicit pathophysiological modifications. However, clinical reports are not adequately integrated with experimental studies examining brain changes occurring post-jmTBI. We monitored the cerebrovascular modifications and assessed the long-term behavioral and electrographic changes resulting from experimental jmTBI. In vivo photoacoustic imaging demonstrated a decrease of cerebrovascular oxygen saturation levels in the impacted area hours post-jmTBI. Three days post-jmTBI oxygenation returned to pre-jmTBI levels, stabilizing at 7 and 30 days after the injury. At the functional level, cortical arterioles displayed no NMDA vasodilation response, while vasoconstriction induced by thromboxane receptor agonist was enhanced at 1 day post-jmTBI. Arterioles showed abnormal NMDA vasodilation at 3 days post-jmTBI, returning to normality at 7 days post injury. Histology showed changes in vessel diameters from 1 to 30 days post-jmTBI. Neurological evaluation indicated signs of anxiety-like behavior up to 30 days post-jmTBI. EEG recordings performed at the cortical site of impact 30 days post-jmTBI did not indicate seizures activity, although it revealed a reduction of gamma waves as compared to age matched sham. Histology showed decrease of neuronal filament staining. In conclusion, experimental jmTBI triggers an early cerebrovascular hypo‑oxygenation in vivo and faulty vascular reactivity. The exact topographical coherence and the direct casualty between early cerebrovascular changes and the observed long-term neurological modifications remain to be investigated. A potential translational value for cerebro-vascular oxygen monitoring in jmTBI is discussed.
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Affiliation(s)
| | | | - Emma Zub
- Cerebrovascular and Glia Research Laboratory, Department of Neuroscience, Institute of Functional Genomics (UMR 5203 CNRS-U1191 INSERM, University of Montpellier), Montpellier, France
| | - Amel Saudi
- Cerebrovascular and Glia Research Laboratory, Department of Neuroscience, Institute of Functional Genomics (UMR 5203 CNRS-U1191 INSERM, University of Montpellier), Montpellier, France
| | | | | | - Pierre Sicard
- INSERM, CNRS, Université de Montpellier, PhyMedExp, IPAM, Montpellier, France
| | - André Obenaus
- CNRS UMR5287, University of Bordeaux, Bordeaux, France; Department of Pediatrics, Loma Linda University School of Medicine, Loma Linda, CA, USA; Basic Science Department, Loma Linda University School of Medicine, Loma Linda, CA, USA; Center for Glial-Neuronal Interactions, Division of Biomedical Sciences, UC Riverside, Riverside, CA, USA; Department of Pediatrics, University of California, Irvine, Irvine, CA, USA
| | - Nicola Marchi
- Cerebrovascular and Glia Research Laboratory, Department of Neuroscience, Institute of Functional Genomics (UMR 5203 CNRS-U1191 INSERM, University of Montpellier), Montpellier, France.
| | - Jerome Badaut
- CNRS UMR5287, University of Bordeaux, Bordeaux, France; Basic Science Department, Loma Linda University School of Medicine, Loma Linda, CA, USA.
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21
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Maksoud S, Lawson McLean A, Bauer J, Schwarz F, Waschke A. Penetrating traumatic brain injury resulting from a cockerel attack: case report and literature review. Childs Nerv Syst 2020; 36:1067-1070. [PMID: 31784819 DOI: 10.1007/s00381-019-04441-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 11/08/2019] [Indexed: 11/25/2022]
Abstract
Traumatic brain injury is common in children and can lead to death or considerable, long-lasting morbidity. We present the case of a 10-month-old female child who presented after being attacked by a cockerel in a chicken coop. Following a seizure, an MRI scan revealed an intracerebral haemorrhage underlying a stab-type wound inflicted by the bird. Animal bite injuries are common worldwide but they rarely cause intracranial injuries. Domestic hens are rarely dangerous but can become defensive or aggressive during breeding periods or when protecting their territory. To date, only a handful of articles have reported on wounds inflicted by chicken beaks. Those reported were largely facial or ocular injuries. Infectious complications have also been encountered post-injury. This is to our knowledge the first report of a bird attack resulting in significant penetrating traumatic brain injury. Children should be cautioned by guardians to avoid unsupervised contact with chickens, particularly during breeding. Attacks to the neurocranium when they occur must be taken seriously and not treated as humorous or insignificant. Imaging appropriate to the child's clinical condition should be pursued and appropriate intervention and antibiotic treatment should be implemented.
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Affiliation(s)
- Salah Maksoud
- Department of Neurosurgery, Jena University Hospital - Friedrich Schiller University Jena, Am Klinikum 1, 07747, Jena, Germany
| | - Aaron Lawson McLean
- Department of Neurosurgery, Jena University Hospital - Friedrich Schiller University Jena, Am Klinikum 1, 07747, Jena, Germany.
| | - Johannes Bauer
- Department of Neurosurgery, Jena University Hospital - Friedrich Schiller University Jena, Am Klinikum 1, 07747, Jena, Germany
| | - Falko Schwarz
- Department of Neurosurgery, Jena University Hospital - Friedrich Schiller University Jena, Am Klinikum 1, 07747, Jena, Germany
| | - Albrecht Waschke
- Department of Neurosurgery, Jena University Hospital - Friedrich Schiller University Jena, Am Klinikum 1, 07747, Jena, Germany
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22
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Olson A, Ellis MJ, Selci E, Russell K. Delayed Symptom Onset Following Pediatric Sport-Related Concussion. Front Neurol 2020; 11:220. [PMID: 32318012 PMCID: PMC7147522 DOI: 10.3389/fneur.2020.00220] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 03/09/2020] [Indexed: 12/22/2022] Open
Abstract
Objective: (1) To examine the prevalence of delayed symptom onset (DSO) among pediatric sport-related concussion (SRC) patients as well as the effect of symptom onset on initial symptom severity, length of recovery, and development of delayed recovery; (2) to evaluate the impact of symptom onset on sideline management. Methods: We conducted a prospective study of pediatric SRC patients (<20 years of age) evaluated at a multi-disciplinary concussion program. Patients underwent initial medical assessment by a single neurosurgeon and a structured interview by a research assistant. Patients were classified as experiencing early symptom onset (symptom onset <15 min from the time of the suspected injury; ESO) or DSO (≥15 min from the time of the suspected injury). Results: A total of 144 SRC patients (61.1% male; mean age 14.6 years, SD 1.8) evaluated a median of 5.0 days (IQR 4.0, 9.0) post-injury were included in the study. Among these patients, 120 (83.3%) reported experiencing ESO while 24 (16.7%) experienced DSO following injury. Among those that experienced DSO the median length of time from the suspected injury to symptom onset was 60.0 min (IQR 20.0, 720.0). No significant differences were observed in symptom severity at initial medical assessment (median Post-Concussion Symptom Scale score 20.0 vs. 18.0, p = 0.35), length of physician-document clinical recovery (median 22.0 vs. 24.0 days; p = 0.46) or the proportion of those who developed delayed physician-documented clinical recovery (34.4 vs. 42.1%, p = 0.52) among patients with ESO or DSO. Patients who reported experiencing ESO were significantly more likely to be immediately removed from play at the time of their suspected injury compared to those who experienced DSO (71.6% vs. 29.2%; p < 0.0001). Conclusions: This study suggests that an important proportion of children and adolescents who sustain an acute SRC experience DSO. DSO is associated with lower rates of immediate removal from play at the time of suspected injury. Secondary study findings highlight the need for improved sport stakeholder concussion education and standardized concussion protocols that mandate the immediate and permanent removal of all youth with a suspected concussion until they undergo medical assessment.
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Affiliation(s)
- Ashley Olson
- Max Rady College of Medicine Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Michael J Ellis
- Department of Surgery, University of Manitoba, Winnipeg, MB, Canada.,Pediatrics and Child Health, University of Manitoba, Winnipeg, MB, Canada.,Section of Neurosurgery, University of Manitoba, Winnipeg, MB, Canada.,Pan Am Concussion Program, Winnipeg, MB, Canada.,Childrens Hospital Research Institute of Manitoba, Winnipeg, MB, Canada.,Canada North Concussion Network, Winnipeg, MB, Canada
| | - Erin Selci
- Pediatrics and Child Health, University of Manitoba, Winnipeg, MB, Canada.,Childrens Hospital Research Institute of Manitoba, Winnipeg, MB, Canada
| | - Kelly Russell
- Pediatrics and Child Health, University of Manitoba, Winnipeg, MB, Canada.,Childrens Hospital Research Institute of Manitoba, Winnipeg, MB, Canada.,Canada North Concussion Network, Winnipeg, MB, Canada
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23
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Ellis MJ, Russell K. The Potential of Telemedicine to Improve Pediatric Concussion Care in Rural and Remote Communities in Canada. Front Neurol 2019; 10:840. [PMID: 31428043 PMCID: PMC6688625 DOI: 10.3389/fneur.2019.00840] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 07/19/2019] [Indexed: 12/15/2022] Open
Abstract
Concussion is a form of mild traumatic brain injury that affects thousands of Canadian children and adolescents annually. Despite national efforts to harmonize the recognition and management of pediatric concussion in Canada, timely access to primary and specialized care following this injury remains a challenge for many patients especially those who live in rural and remote communities. To address similar challenges facing patients with stroke and other neurological disorders, physicians have begun to leverage advances in telemedicine to improve the delivery of specialized neurological care to those living in medically underserved regions. Preliminary studies suggest that telemedicine may be a safe and cost-effective approach to assist in the medical care of select patients with acute concussion and persistent post-concussion symptoms. Here we provide an overview of telemedicine, teleneurology, the principles of concussion assessment and management, as well as the current state of concussion care in Canada. Utilizing preliminary evidence from studies of telemedicine in concussion and experience from comprehensive systems of care for stroke, we outline steps that must be taken to evaluate the potential of telemedicine-based concussion networks to improve the care of pediatric concussion patients living in underserved rural and remote communities in Canada.
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Affiliation(s)
- Michael J Ellis
- Department of Surgery, University of Manitoba, Winnipeg, MB, Canada.,Pediatrics and Child Health, University of Manitoba, Winnipeg, MB, Canada.,Section of Neurosurgery, University of Manitoba, Winnipeg, MB, Canada.,Children's Hospital Research Institute of Manitoba, Winnipeg, MB, Canada.,Pan Am Concussion Program, Winnipeg, MB, Canada
| | - Kelly Russell
- Pediatrics and Child Health, University of Manitoba, Winnipeg, MB, Canada.,Children's Hospital Research Institute of Manitoba, Winnipeg, MB, Canada
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24
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Rucker JC, Buettner-Ennever JA, Straumann D, Cohen B. Case Studies in Neuroscience: Instability of the visual near triad in traumatic brain injury-evidence for a putative convergence integrator. J Neurophysiol 2019; 122:1254-1263. [PMID: 31339793 DOI: 10.1152/jn.00861.2018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Deficits of convergence and accommodation are common following traumatic brain injury, including mild traumatic brain injury, although the mechanism and localization of these deficits have been unclear and supranuclear control of the near-vision response has been incompletely understood. We describe a patient who developed profound instability of the near-vision response with inability to maintain convergence and accommodation following mild traumatic brain injury, who was identified to have a structural lesion on brain MRI in the pulvinar of the caudal thalamus, the pretectum, and the rostral superior colliculus. We discuss the potential relationship between posttraumatic clinical near-vision response deficits and the MRI lesion in this patient. We further propose that the MRI lesion location, specifically the rostral superior colliculus, participates in neural integration for convergence holding, given its proven anatomic connections with the central mesencephalic reticular formation and C-group medial rectus motoneurons in the oculomotor nucleus, which project to extraocular muscle nontwitch fibers specialized for fatigue-resistant, slow, tonic activity such as vergence holding.NEW & NOTEWORTHY Supranuclear control of the near-vision response has been incompletely understood to date. We propose, based on clinical and anatomic evidence, functional pathways for vergence that participate in the generation of the near triad, "slow vergence," and vergence holding.
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Affiliation(s)
- Janet C Rucker
- Departments of Neurology and Ophthalmology, New York University School of Medicine, New York, New York
| | | | - Dominik Straumann
- Department of Neurology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.,Swiss Concussion Center, Zurich, Switzerland
| | - Bernard Cohen
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, New York
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25
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Exploring Sex-Based Differences in Concussion Knowledge, Attitudes and Resources in Young First Nations Hockey Players: A Cross-Sectional Survey from Ontario, Canada. BRAIN IMPAIR 2019. [DOI: 10.1017/brimp.2019.18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
AbstractObjective:Indigenous youth are vulnerable to concussion when playing hockey. A clear characterisation of sex differences among Indigenous youth could assist in tailoring future education programmes for prevention and management of concussion. The purpose of this study was to compare and contrast concussion knowledge, attitudes and resources in First Nations girls and boys playing recreational hockey.Method:The cross-sectional survey was conducted in partnership with a First Nations’ chief, other Indigenous community leaders and a tertiary care head injury clinic. In Canada, researchers engaging with Indigenous peoples are expected to adhere to principles of Ownership, Control, Access and Possessions. The study included Indigenous boys and girls between the ages of 10 and 18 years of age.Results:More girls attending the hockey tournament participated in the study as compared to boys (girlsn= 46, boysn= 29). More girls reported they had never experienced a concussion (73.9%), as compared to boys (58.6%) self-reports. Less than half of all study participants were able to identify some signs and symptoms of concussion such as vomiting/nausea, memory problems, fatigue and blurred vision and recognition of several concussion symptoms varied by sex.Conclusions:We created a unique partnership between Indigenous leaders and tertiary care clinic staff. Among Indigenous youth reasons for not reporting concussion symptoms to the coach varied by sex (although not reaching statistical significance), suggesting concussion education warrants tailoring for girls and boys.
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26
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Hiskens MI, Angoa-Pérez M, Schneiders AG, Vella RK, Fenning AS. Modeling sports-related mild traumatic brain injury in animals-A systematic review. J Neurosci Res 2019; 97:1194-1222. [PMID: 31135069 DOI: 10.1002/jnr.24472] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 04/22/2019] [Accepted: 05/07/2019] [Indexed: 12/14/2022]
Abstract
Sports-related head trauma has emerged as an important public health issue, as mild traumatic brain injuries (mTBIs) may result in neurodegenerative disorders such as chronic traumatic encephalopathy (CTE). Research into mTBI and CTE pathophysiology are difficult to undertake in athletes, with observational trials and post-mortem analysis the current mainstays. Thus, animal models play an important role in the study of mTBI, however, traditional animal models have focused on acute, severe injuries rather than the more typical mTBI's seen in sport injuries. Recently, a number of animal models have been developed that are both appropriately scaled and biomechanically relevant to the forces sustained by athletes. This review aimed to examine the literature for variables included in these animal models, and the resulting neurotrauma as evidenced by pathology and behavioral deficits. A systematic search of the literature was performed in multiple electronic databases. The inclusion criteria required mimicry of athlete mTBI conditions: freedom of head movement, lack of surgical alteration of the skull, and application of direct contact force. Studies were analyzed for variables including apparatus design features (impact force, change in animal head velocity, and kinetic energy transfer to the head), demonstrated pathology (phosphorylated tau, TDP-43 aggregation, diffuse axonal injury, gliosis, cytokine inflammation response, and genetic integrity), and behavioral changes. These studies suggested that appropriate animal models can assist in understanding the pathological and functional outcomes of athlete mTBI, and could be used as a platform for future studies of diagnostic/prognostic markers and in the development of treatment interventions.
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Affiliation(s)
- Matthew I Hiskens
- School of Health, Medical and Applied Sciences, Central Queensland University, Rockhampton, Australia
| | - Mariana Angoa-Pérez
- Research & Development Service, John D. Dingell VA Medical Center, Detroit, Michigan.,Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan
| | - Anthony G Schneiders
- School of Health, Medical and Applied Sciences, Central Queensland University, Branyan, Australia
| | - Rebecca K Vella
- School of Health, Medical and Applied Sciences, Central Queensland University, Rockhampton, Australia
| | - Andrew S Fenning
- School of Health, Medical and Applied Sciences, Central Queensland University, Rockhampton, Australia
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Zhang Y, Chopp M, Gang Zhang Z, Zhang Y, Zhang L, Lu M, Zhang T, Winter S, Brandstätter H, Mahmood A, Xiong Y. Prospective, randomized, blinded, and placebo-controlled study of Cerebrolysin dose-response effects on long-term functional outcomes in a rat model of mild traumatic brain injury. J Neurosurg 2018; 129:1295-1304. [PMID: 29303438 DOI: 10.3171/2017.6.jns171007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 06/20/2017] [Indexed: 01/30/2023]
Abstract
Using a prospective, randomized, blinded, placebo-controlled protocol, the authors demonstrated that Cerebrolysin at doses of 0.8-7.5 ml/kg, administered 4 hours after injury and then once daily for a total of 10 consecutive days, improves long-term functional outcomes in a rat model of mild closed head injury; a 2.5-ml/kg dose was identified as optimal. These findings suggest that Cerebrolysin has the potential to treat mild traumatic brain injury, the incidence of which is high without effective treatments.
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Affiliation(s)
| | - Michael Chopp
- 2Neurology, and
- 3Department of Physics, Oakland University, Rochester, Michigan; and
| | | | | | | | - Mei Lu
- 4Biostatistics and Research Epidemiology, Henry Ford Hospital, Detroit, Michigan
| | - Talan Zhang
- 4Biostatistics and Research Epidemiology, Henry Ford Hospital, Detroit, Michigan
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28
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Sullivan KA, Hills AP, Iverson GL. Graded Combined Aerobic Resistance Exercise (CARE) to Prevent or Treat the Persistent Post-concussion Syndrome. Curr Neurol Neurosci Rep 2018; 18:75. [DOI: 10.1007/s11910-018-0884-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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30
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Affiliation(s)
- Davin K Quinn
- From the Department of Psychiatry and Behavioral Sciences, the MIND Research Network, and the Department of Psychology, University of New Mexico, Albuquerque; the Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, and the Division of Orthopedics and Sports Medicine, Children's Hospital of Philadelphia, Philadelphia; and the Departments of Psychiatry and Behavioral Sciences and of Physical Medicine and Rehabilitation, University of Washington, Seattle
| | - Andrew R Mayer
- From the Department of Psychiatry and Behavioral Sciences, the MIND Research Network, and the Department of Psychology, University of New Mexico, Albuquerque; the Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, and the Division of Orthopedics and Sports Medicine, Children's Hospital of Philadelphia, Philadelphia; and the Departments of Psychiatry and Behavioral Sciences and of Physical Medicine and Rehabilitation, University of Washington, Seattle
| | - Christina L Master
- From the Department of Psychiatry and Behavioral Sciences, the MIND Research Network, and the Department of Psychology, University of New Mexico, Albuquerque; the Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, and the Division of Orthopedics and Sports Medicine, Children's Hospital of Philadelphia, Philadelphia; and the Departments of Psychiatry and Behavioral Sciences and of Physical Medicine and Rehabilitation, University of Washington, Seattle
| | - Jesse R Fann
- From the Department of Psychiatry and Behavioral Sciences, the MIND Research Network, and the Department of Psychology, University of New Mexico, Albuquerque; the Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, and the Division of Orthopedics and Sports Medicine, Children's Hospital of Philadelphia, Philadelphia; and the Departments of Psychiatry and Behavioral Sciences and of Physical Medicine and Rehabilitation, University of Washington, Seattle
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31
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Zhang BL, Fan YS, Wang JW, Zhou ZW, Wu YG, Yang MC, Sun DD, Zhang JN. Cognitive impairment after traumatic brain injury is associated with reduced long-term depression of excitatory postsynaptic potential in the rat hippocampal dentate gyrus. Neural Regen Res 2018; 13:1753-1758. [PMID: 30136690 PMCID: PMC6128047 DOI: 10.4103/1673-5374.238618] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Traumatic brain injury can cause loss of neuronal tissue, remote symptomatic epilepsy, and cognitive deficits. However, the mechanisms underlying the effects of traumatic brain injury are not yet clear. Hippocampal excitability is strongly correlated with cognitive dysfunction and remote symptomatic epilepsy. In this study, we examined the relationship between traumatic brain injury-induced neuronal loss and subsequent hippocampal regional excitability. We used hydraulic percussion to generate a rat model of traumatic brain injury. At 7 days after injury, the mean modified neurological severity score was 9.5, suggesting that the neurological function of the rats was remarkably impaired. Electrophysiology and immunocytochemical staining revealed increases in the slope of excitatory postsynaptic potentials and long-term depression (indicating weakened long-term inhibition), and the numbers of cholecystokinin and parvalbumin immunoreactive cells were clearly reduced in the rat hippocampal dentate gyrus. These results indicate that interneuronal loss and changes in excitability occurred in the hippocampal dentate gyrus. Thus, traumatic brain injury-induced loss of interneurons appears to be associated with reduced long-term depression in the hippocampal dentate gyrus.
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Affiliation(s)
- Bao-Liang Zhang
- Department of Neurosurgery, Tianjin Medical University General Hospital; Tianjin Neurological Institute; Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education; Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin, China
| | - Yue-Shan Fan
- Department of Neurosurgery, Tianjin Medical University General Hospital; Tianjin Neurological Institute; Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education; Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin, China
| | - Ji-Wei Wang
- Department of Neurosurgery, Tianjin Medical University General Hospital; Tianjin Neurological Institute; Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education; Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin, China
| | - Zi-Wei Zhou
- Department of Neurosurgery, Tianjin Medical University General Hospital; Tianjin Neurological Institute; Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education; Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin, China
| | - Yin-Gang Wu
- Department of Neurosurgery, Tianjin Medical University General Hospital; Tianjin Neurological Institute; Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education; Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin, China
| | - Meng-Chen Yang
- Department of Neurosurgery, Tianjin Medical University General Hospital; Tianjin Neurological Institute; Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education; Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin, China
| | - Dong-Dong Sun
- Department of Neurosurgery, Tianjin Medical University General Hospital; Tianjin Neurological Institute; Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education; Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin, China
| | - Jian-Ning Zhang
- Department of Neurosurgery, Tianjin Medical University General Hospital; Tianjin Neurological Institute; Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education; Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin, China
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32
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Hamblin MR. Photobiomodulation for traumatic brain injury and stroke. J Neurosci Res 2017; 96:731-743. [PMID: 29131369 DOI: 10.1002/jnr.24190] [Citation(s) in RCA: 122] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 10/04/2017] [Accepted: 10/04/2017] [Indexed: 12/12/2022]
Abstract
There is a notable lack of therapeutic alternatives for what is fast becoming a global epidemic of traumatic brain injury (TBI). Photobiomodulation (PBM) employs red or near-infrared (NIR) light (600-1100nm) to stimulate healing, protect tissue from dying, increase mitochondrial function, improve blood flow, and tissue oxygenation. PBM can also act to reduce swelling, increase antioxidants, decrease inflammation, protect against apoptosis, and modulate microglial activation state. All these mechanisms of action strongly suggest that PBM delivered to the head should be beneficial in cases of both acute and chronic TBI. Most reports have used NIR light either from lasers or from light-emitting diodes (LEDs). Many studies in small animal models of acute TBI have found positive effects on neurological function, learning and memory, and reduced inflammation and cell death in the brain. There is evidence that PBM can help the brain repair itself by stimulating neurogenesis, upregulating BDNF synthesis, and encouraging synaptogenesis. In healthy human volunteers (including students and healthy elderly women), PBM has been shown to increase regional cerebral blood flow, tissue oxygenation, and improve memory, mood, and cognitive function. Clinical studies have been conducted in patients suffering from the chronic effects of TBI. There have been reports showing improvement in executive function, working memory, and sleep. Functional magnetic resonance imaging has shown modulation of activation in intrinsic brain networks likely to be damaged in TBI (default mode network and salience network).
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Affiliation(s)
- Michael R Hamblin
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA.,Department of Dermatology, Harvard Medical School, Boston, MA.,Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA
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Namjoshi DR, Cheng WH, Bashir A, Wilkinson A, Stukas S, Martens KM, Whyte T, Abebe ZA, McInnes KA, Cripton PA, Wellington CL. Defining the biomechanical and biological threshold of murine mild traumatic brain injury using CHIMERA (Closed Head Impact Model of Engineered Rotational Acceleration). Exp Neurol 2017; 292:80-91. [DOI: 10.1016/j.expneurol.2017.03.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 02/18/2017] [Accepted: 03/03/2017] [Indexed: 01/05/2023]
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