Journal of neurotrauma
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Journal of neurotrauma · Jun 2022
Brain-Derived Extracellular Vesicles Induce Vasoconstriction and Reduce Cerebral Blood Flow in Mice.
Traumatic brain injury (TBI) impairs cerebrovascular autoregulation and reduces cerebral blood flow (CBF), leading to ischemic secondary injuries. We have shown that injured brains release brain-derived extracellular vesicles (BDEVs) into circulation, where they cause a systemic hypercoagulable state that rapidly turns into consumptive coagulopathy. The BDEVs induce endothelial injury and permeability, leading to the hypothesis that they contribute to TBI-induced cerebrovascular dysregulation. ⋯ It was prevented by the calcium channel blocker nimodipine. When being separated, neither protein nor phospholipid components from the lethal number of BDEVs induced vasoconstriction, reduced CBF, and caused death. These results demonstrate a novel vasoconstrictive activity of BDEVs that depends on the structure of BDEVs and contributes to TBI-induced disseminated cerebral ischemia and sudden death.
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Journal of neurotrauma · Jun 2022
History of Mild Traumatic Brain Injury Affects Static Balance Under Complex Multisensory Manipulations.
A recent study in active-duty military in the Coast Guard suggested that lifetime experience with mild traumatic brain injury (mTBI) was associated with subtle deficits in postural control when exposed to multi-sensory discordance (i.e., rotating visual stimulation). The present study extended postural assessments to veterans recruited from the community. Service veterans completed the Defense Veteran Brain Injury Center TBI Screening Tool, Post-Traumatic Stress Disorder (PTSD) Checklist (PCL-5), and Neurobehavioral Symptom Inventory (NSI). ⋯ Increased postural sway was not related to PTSD, NSI, or balance-specific symptom expression. In summary, veterans who experienced mTBI over their lifetime exhibited dysfunction in balance control as revealed by challenging conditions with multi-sensory discordance. These balance-related signs were independent of self-reported balance-related symptoms or other symptom domains measured by the NSI, which can provide a method for exposing otherwise covert dysfunction long after the experience of mTBI.
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Journal of neurotrauma · Jun 2022
ReviewNeuroimaging correlates of depression after traumatic brain injury: A systematic review.
Depression is the most frequent neuropsychiatric complication after traumatic brain injury (TBI) and is associated with poorer outcomes. Neuroimaging has the potential to improve our understanding of the neural correlates of depression after TBI and may improve our capacity to accurately predict and effectively treat this condition. We conducted a systematic review of structural and functional neuroimaging studies that examined the association between depression after TBI and neuroimaging measures. ⋯ Findings that were replicated in more than one study included reduced gray matter in the rostral anterior cingulate cortex, pre-frontal cortex, and hippocampus, and damage in five white matter tracts (cingulum, internal capsule, superior longitudinal fasciculi, and anterior and posterior corona radiata). This systematic review found that the available data did not converge on a clear neuroimaging biomarker for depression after TBI. However, there are promising targets that warrant further study.
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Journal of neurotrauma · Jun 2022
Decompressive craniectomy practice following traumatic brain injury, in comparison with randomized trials.
High quality evidence shows decompressive craniectomy (DC) following traumatic brain injury (TBI) may improve survival but increase the number of severely disabled survivors. Contemporary international practice is unknown. We sought to describe international use of DC, and the alignment with evidence and clinical practice guidelines, by analyzing the harmonized Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) and Australia-Europe NeuroTrauma Effectiveness Research in Traumatic Brain Injury (OzENTER-TBI) core study datasets, which include patients admitted to intensive care units (ICUs) in Europe, the United Kingdom, and Australia between 2015 and 2017. ⋯ Of patients who underwent DC, 258/320 (80.6%) were ineligible for either trial: 149/320 (46.6%) underwent primary DC, 62/320 (19.4%) were outside the trials' age criteria, and 126/320 (39.4%) did not develop intracranial hypertension refractory to non-operative therapies prior to DC. Secondary DC was used infrequently in patients in whom it had been shown to increase survival with severe disability, indicating alignment between contemporaneous evidence and practice. However, most patients who underwent DC were ineligible for the key trials; whether they benefited from DC remains unknown.