scholarly journals Meningeal blood–brain barrier disruption in acute traumatic brain injury

2020 ◽  
Vol 2 (2) ◽  
Author(s):  
Lisa Christine Turtzo ◽  
Neekita Jikaria ◽  
Martin R Cota ◽  
Joshua P Williford ◽  
Victoria Uche ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Contrast Enhancement ◽  
Mild Traumatic Brain Injury ◽  
Subarachnoid Space ◽  
Meningeal Enhancement ◽  
Contrast Enhanced ◽  
Acute Traumatic Brain Injury ◽  
The Brain ◽  
Contrast Enhanced Mri

Abstract The meninges serve as a functional barrier surrounding the brain, critical to the immune response, and can be compromised following head trauma. Meningeal enhancement can be detected on contrast-enhanced MRI in patients presenting with acute traumatic brain injury, even when head CT is negative. Following head trauma, gadolinium-based contrast appears to extravasate from the vasculature, enhancing the dura within minutes, and later permeates the subarachnoid space. The aims of this study were to characterize the initial kinetics of the uptake of contrast agent after injury and the delayed redistribution of contrast enhancement in the subarachnoid space in hyperacute patients. Neuroimaging was obtained prospectively in two large ongoing observational studies of patients aged 18 years or older presenting to the emergency department with suspected acute head injury. Dynamic contrast-enhanced MRI studies in a cohort of consecutively enrolling patients with mild traumatic brain injury (n = 36) determined that the kinetic half-life of dural-related meningeal enhancement was 1.3 ± 0.6 min (95% enhancement within 6 min). The extravasation of contrast into the subarachnoid space was investigated in a cohort of CT negative mild traumatic brain injury patients initially imaged within 6 h of injury (hyperacute) who subsequently underwent a delayed MRI, with no additional contrast administration, several hours after the initial MRI. Of the 32 patients with delayed post-contrast imaging, 18 (56%) had conspicuous expansion of the contrast enhancement into the subarachnoid space, predominantly along the falx and superior sagittal sinus. Patients negative for traumatic meningeal enhancement on initial hyperacute MRI continued to have no evidence of meningeal enhancement on the delayed MRI. These studies demonstrate that (i) the initial enhancement of the traumatically injured meninges occurs within minutes of contrast injection, suggesting highly permeable meningeal vasculature, and that (ii) contrast in the meninges redistributes within the subarachnoid space over the period of hours, suggesting a compromise in the blood–brain and/or blood-cerebrospinal barriers. Data from the parent study indicate that up to one in two patients with mild traumatic brain injury have traumatic brain injury on acute (<48 h) MRI, with a higher prevalence seen in patients with moderate or severe traumatic brain injury. The current study’s findings of traumatic meningeal enhancement and the subsequent delayed extravasation of contrast into the subarachnoid spaces indicate that a substantial percentage of patients with even mild traumatic brain injury may have a transient disruption in barriers separating the vasculature from the brain.

scholarly journals Slow blood-to-brain transport underlies enduring barrier dysfunction in American football players

Brain ◽  
2020 ◽  
Vol 143 (6) ◽  
pp. 1826-1842 ◽  
Author(s):  
Ronel Veksler ◽  
Udi Vazana ◽  
Yonatan Serlin ◽  
Ofer Prager ◽  
Jonathan Ofer ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
White Matter ◽  
Mild Traumatic Brain Injury ◽  
American Football ◽  
Football Players ◽  
Barrier Dysfunction ◽  
Dynamic Contrast Enhanced ◽  
Contrast Enhanced ◽  
Contrast Enhanced Mri

Abstract Repetitive mild traumatic brain injury in American football players has garnered increasing public attention following reports of chronic traumatic encephalopathy, a progressive tauopathy. While the mechanisms underlying repetitive mild traumatic brain injury-induced neurodegeneration are unknown and antemortem diagnostic tests are not available, neuropathology studies suggest a pathogenic role for microvascular injury, specifically blood–brain barrier dysfunction. Thus, our main objective was to demonstrate the effectiveness of a modified dynamic contrast-enhanced MRI approach we have developed to detect impairments in brain microvascular function. To this end, we scanned 42 adult male amateur American football players and a control group comprising 27 athletes practicing a non-contact sport and 26 non-athletes. MRI scans were also performed in 51 patients with brain pathologies involving the blood–brain barrier, namely malignant brain tumours, ischaemic stroke and haemorrhagic traumatic contusion. Based on data from prolonged scans, we generated maps that visualized the permeability value for each brain voxel. Our permeability maps revealed an increase in slow blood-to-brain transport in a subset of amateur American football players, but not in sex- and age-matched controls. The increase in permeability was region specific (white matter, midbrain peduncles, red nucleus, temporal cortex) and correlated with changes in white matter, which were confirmed by diffusion tensor imaging. Additionally, increased permeability persisted for months, as seen in players who were scanned both on- and off-season. Examination of patients with brain pathologies revealed that slow tracer accumulation characterizes areas surrounding the core of injury, which frequently shows fast blood-to-brain transport. Next, we verified our method in two rodent models: rats and mice subjected to repeated mild closed-head impact injury, and rats with vascular injury inflicted by photothrombosis. In both models, slow blood-to-brain transport was observed, which correlated with neuropathological changes. Lastly, computational simulations and direct imaging of the transport of Evans blue-albumin complex in brains of rats subjected to recurrent seizures or focal cerebrovascular injury suggest that increased cellular transport underlies the observed slow blood-to-brain transport. Taken together, our findings suggest dynamic contrast-enhanced-MRI can be used to diagnose specific microvascular pathology after traumatic brain injury and other brain pathologies.

Providing Care of Mild Traumatic Brain Injury by the Family Practice/Primary Care Optometrist

2018 ◽  
pp. 110-119
Keyword(s):  
Primary Care ◽  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Mild Traumatic Brain Injury ◽  
Family Practice ◽  
Advanced Training ◽  
Entry Level ◽  
The Family ◽  
Basic Understanding ◽  
The Brain

Primary Objectives: By extending the scope of knowledge of the primary care optometrist, the brain injury population will have expanded access to entry level neurooptometric care by optometric providers who have a basic understanding of their neurovisual problems, be able to provide some treatment and know when to refer to their colleagues who have advanced training in neuro-optometric rehabilitation.

scholarly journals What are the strongest indicators of intracerebral hemorrhage in mild traumatic brain injury?

2021 ◽  
Vol 6 (1) ◽  
pp. e000717
Author(s):  
Panu Teeratakulpisarn ◽  
Phati Angkasith ◽  
Thanakorn Wannakul ◽  
Parichat Tanmit ◽  
Supatcha Prasertcharoensuk ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
High Risk ◽  
Ct Scan ◽  
Mild Traumatic Brain Injury ◽  
Skull Fracture ◽  
Brain Ct ◽  
Baseline Characteristics ◽  
Gcs Score ◽  
The Brain

BackgroundAlthough there are eight factors known to indicate a high risk of intracranial hemorrhage (ICH) in mild traumatic brain injury (TBI), identification of the strongest of these factors may optimize the utility of brain CT in clinical practice. This study aimed to evaluate the predictors of ICH based on baseline characteristics/mode of injury, indications for brain CT, and a combination of both to determine the strongest indicator.MethodsThis was a descriptive, retrospective, analytical study. The inclusion criteria were diagnosis of mild TBI, high risk of ICH, and having undergone a CT scan of the brain. The outcome of the study was any type of ICH. Stepwise logistic regression analysis was used to find the strongest predictors according to three models: (1) injury pattern and baseline characteristics, (2) indications for CT scan of the brain, and (3) a combination of models 1 and 2.ResultsThere were 100 patients determined to be at risk of ICH based on indications for CT of the brain in patients with acute head injury. Of these, 24 (24.00%) had ICH. Model 1 found that injury due to motor vehicle crash was a significant predictor of ICH, with an adjusted OR (95% CI) of 11.53 (3.05 to 43.58). Models 2 and 3 showed Glasgow Coma Scale (GCS) score of 13 to 14 after 2 hours of observation and open skull or base of skull fracture to be independent predictors, with adjusted OR (95% CI) of 11.77 (1.32 to 104.96) and 5.88 (1.08 to 31.99) according to model 2.DiscussionOpen skull or base of skull fracture and GCS score of 13 to 14 after 2 hours of observation were the two strongest predictors of ICH in mild TBI.Level of evidenceIII.

scholarly journals GPR110 ligands reduce chronic optic tract gliosis and visual deficit following repetitive mild traumatic brain injury in mice

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Huazhen Chen ◽  
Karl Kevala ◽  
Elma Aflaki ◽  
Juan Marugan ◽  
Hee-Yong Kim
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Mild Traumatic Brain Injury ◽  
Visual Evoked Potential ◽  
Evoked Potential ◽  
Optic Tract ◽  
Primary Microglia ◽  
Visual Dysfunction ◽  
The Brain

Abstract Background Repetitive mild traumatic brain injury (mTBI) can result in chronic visual dysfunction. G-protein receptor 110 (GPR110, ADGRF1) is the target receptor of N-docosahexaenoylethanolamine (synaptamide) mediating the anti-neuroinflammatory function of synaptamide. In this study, we evaluated the effect of an endogenous and a synthetic ligand of GPR110, synaptamide and (4Z,7Z,10Z,13Z,16Z,19Z)-N-(2-hydroxy-2-methylpropyl) docosa-4,7,10,13,16,19-hexaenamide (dimethylsynaptamide, A8), on the mTBI-induced long-term optic tract histopathology and visual dysfunction using Closed-Head Impact Model of Engineered Rotational Acceleration (CHIMERA), a clinically relevant model of mTBI. Methods The brain injury in wild-type (WT) and GPR110 knockout (KO) mice was induced by CHIMERA applied daily for 3 days, and GPR110 ligands were intraperitoneally injected immediately following each impact. The expression of GPR110 and proinflammatory mediator tumor necrosis factor (TNF) in the brain was measured by using real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) in an acute phase. Chronic inflammatory responses in the optic tract and visual dysfunction were assessed by immunostaining for Iba-1 and GFAP and visual evoked potential (VEP), respectively. The effect of GPR110 ligands in vitro was evaluated by the cyclic adenosine monophosphate (cAMP) production in primary microglia isolated from adult WT or KO mouse brains. Results CHIMERA injury acutely upregulated the GPR110 and TNF gene level in mouse brain. Repetitive CHIMERA (rCHIMERA) increased the GFAP and Iba-1 immunostaining of glia cells and silver staining of degenerating axons in the optic tract with significant reduction of N1 amplitude of visual evoked potential at up to 3.5 months after injury. Both GPR110 ligands dose- and GPR110-dependently increased cAMP in cultured primary microglia with A8, a ligand with improved stability, being more effective than synaptamide. Intraperitoneal injection of A8 at 1 mg/kg or synaptamide at 5 mg/kg significantly reduced the acute expression of TNF mRNA in the brain and ameliorated chronic optic tract microgliosis, astrogliosis, and axonal degeneration as well as visual deficit caused by injury in WT but not in GPR110 KO mice. Conclusion Our data demonstrate that ligand-induced activation of the GPR110/cAMP system upregulated after injury ameliorates the long-term optic tract histopathology and visual impairment caused by rCHIMERA. Based on the anti-inflammatory nature of GPR110 activation, we suggest that GPR110 ligands may have therapeutic potential for chronic visual dysfunction associated with mTBI.

scholarly journals Neuromodulation for Mild Traumatic Brain Injury Rehabilitation: A Systematic Review

2020 ◽  
Vol 14 ◽  
Author(s):  
Francesca Buhagiar ◽  
Melinda Fitzgerald ◽  
Jason Bell ◽  
Fiona Allanson ◽  
Carmela Pestell
Keyword(s):  
Quality Of Life ◽  
Systematic Review ◽  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Mild Traumatic Brain Injury ◽  
Post Intervention ◽  
Persistent Symptoms ◽  
Positive Effects ◽  
The Brain

Background: Mild traumatic brain injury (mTBI) results from an external force to the head or body causing neurophysiological changes within the brain. The number and severity of symptoms can vary, with some individuals experiencing rapid recovery, and others having persistent symptoms for months to years, impacting their quality of life. Current rehabilitation is limited in its ability to treat persistent symptoms and novel approaches are being sought to improve outcomes following mTBI. Neuromodulation is one technique used to encourage adaptive neuroplasticity within the brain.Objective: To systematically review the literature on the efficacy of neuromodulation in the mTBI population.Method: A systematic review was conducted using Medline, Embase, PsycINFO, PsycARTICLES and EBM Review. Preferred Reporting Items for Systematic Reviews and the Synthesis Without Meta-analysis reporting guidelines were used and a narrative review of the selected studies was completed. Fourteen articles fulfilled the inclusion criteria which were published in English, investigating an adult sample and using a pre- and post-intervention design. Studies were excluded if they included non-mild TBI severities, pediatric or older adult populations.Results: Thirteen of fourteen studies reported positive reductions in mTBI symptomatology following neuromodulation. Specifically, improvements were reported in post-concussion symptom ratings, headaches, dizziness, depression, anxiety, sleep disturbance, general disability, cognition, return to work and quality of life. Normalization of working memory activation patterns, vestibular field potentials, hemodynamics of the dorsolateral prefrontal cortex and excessive delta wave activity were also seen. The studies reviewed had several methodological limitations including small, heterogenous samples and varied intervention protocols, limiting generalisability. Further research is required to understand the context in which neuromodulation may be beneficial.Conclusions: While these positive effects are observed, limitations included unequal representation of neuromodulation modalities in the literature, and lack of literature describing the efficacy of neuromodulation on the development or duration of persistent mTBI symptoms. Better clarity regarding neuromodulation efficacy could have a significant impact on mTBI patients, researchers, clinicians, and policy makers, facilitating a more productive post-mTBI population. Despite the limitations, the literature indicates that neuromodulation warrants further investigation. PROSPERO registration number: CRD42020161279.

Practical Challenges in Collecting Head Impact Biomechanics Data in Real-World Scenarios via a Helmet-Based Accelerometer System

2013 ◽  
Author(s):  
Mari A. Allison ◽  
Yun Seok Kang ◽  
Matthew R. Maltese ◽  
John H. Bolte ◽  
Kristy B. Arbogast
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Mild Traumatic Brain Injury ◽  
Real World ◽  
Head Impact ◽  
Permanent Damage ◽  
Head Impact Biomechanics ◽  
Impact Biomechanics ◽  
The Brain

Recent studies have shown that mild traumatic brain injury (mTBI) can have long-term neurological consequences and may cause permanent damage to the brain [1,2]. Given estimates that millions of these injuries occur each year [3], this knowledge has created a demand for countermeasures to prevent mTBI. In order to create countermeasures, the biomechanical inputs leading to mTBI, which are still a matter of debate, must be better understood in both children and adults.

Serendipity and the Subdural Hematoma

Biofeedback ◽  
2009 ◽  
Vol 37 (3) ◽  
pp. 108-111
Author(s):  
Jay Gunkelman
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Mild Traumatic Brain Injury ◽  
Subdural Hematoma ◽  
Imaging Studies ◽  
Word Finding ◽  
Life Threatening ◽  
The Individual ◽  
The Brain ◽  
Effect Of Age

Abstract Mild traumatic brain injury is often missed in the course of treating other injuries. This failure to identify the brain injury can be critically important, even life threatening. This report shows one such case in which the brain injury was overlooked, possibly because of the differential effect of age on the severity of the damage incurred from what appeared to be a mild trauma. Distant to the time of the injury, deficits in speech fluency and word finding led the individual to seek further evaluation, and imaging studies revealed a large subdural hematoma. CT scan images are included.

Resveratrol decreases inflammation in the brain of mice with mild traumatic brain injury

2013 ◽  
Vol 74 (2) ◽  
pp. 470-475 ◽  
Author(s):  
Joshua W. Gatson ◽  
Ming-Mei Liu ◽  
Kareem Abdelfattah ◽  
Jane G. Wigginton ◽  
Scott Smith ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Mild Traumatic Brain Injury ◽  
The Brain

Multiple mild traumatic brain injury in the rat produces persistent pathological alterations in the brain

2017 ◽  
Vol 297 ◽  
pp. 62-72 ◽  
Author(s):  
Diane M. Brooks ◽  
Sarjubhai A. Patel ◽  
Eric D. Wohlgehagen ◽  
Erin O. Semmens ◽  
Alan Pearce ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Mild Traumatic Brain Injury ◽  
The Brain
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