Articles: traumatic-brain-injuries.
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Journal of neurotrauma · Jul 2015
Distributions of MR Diffusion and Spectroscopy Measures with Traumatic Brain Injury.
Magnetic resonance spectroscopy (MRS) and diffusion tensor imaging (DTI) studies have demonstrated that measures of altered metabolism and axonal injury can be detected following traumatic brain injury. The aim of this study was to characterize and compare the distributions of altered image parameters obtained by these methods in subjects with a range of injury severity and to examine their relative sensitivity for diagnostic imaging in this group of subjects. DTI and volumetric magnetic resonance spectroscopic imaging data were acquired in 40 subjects that had experienced a closed-head traumatic brain injury, with a median of 36 d post-injury. ⋯ The between-group analysis revealed widespread alteration of tissue metabolites that was most strongly characterized by increased choline throughout the cerebrum and cerebellum, reaching as much as 40% increase from control values for the group with the worse cognitive assessment score. In contrast, the between-group comparison of DTI measures revealed only minor differences; however, the Z-score image analysis of individual subject DTI parameters revealed regions of altered values relative to controls throughout the major white matter tracts, but with considerable heterogeneity between subjects and with a smaller extent than the findings for altered metabolite measures. The findings of this study illustrate the complimentary nature of these neuroimaging methods.
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Journal of neurotrauma · Jul 2015
Interferon Stimulated Gene 15 upregulation precedes the development of blood brain barrier disruption and cerebral edema after traumatic brain injury in young mice.
Recent studies show that myosin light chain kinase (MLCK) plays a pivotal role in development of cerebral edema, a known complication following traumatic brain injury (TBI) in children and a contributing factor to worsened neurologic recovery. Interferon-stimulated gene 15 (ISG15) is upregulated after cerebral ischemia and is neuroprotective. The significant role of ISG15 after TBI has not been studied. ⋯ PND24 mice showed peak ISG15 expression at 6 h, and PND21 mice at 72 h. MLCK peaked in both age groups at 12 h and co-localized with ISG15 on immunohistochemistry and co-immunoprecipitation. These studies provide evidence, ISG15 is elevated following TBI in mice, preceding MLCK elevation, development of BBB disruption, and cerebral edema.
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Traumatic brain injury (TBI) often results in traumatic axonal injury and white matter (WM) damage, particularly to the corpus callosum (CC). Damage to the CC can lead to impaired performance on neurocognitive tasks, but there is a high degree of heterogeneity in impairment following TBI. Here we examined the relation between CC microstructure and function in pediatric TBI. We used high angular resolution diffusion-weighted imaging (DWI) to evaluate the structural integrity of the CC in humans following brain injury in a sample of 32 children (23 males and 9 females) with moderate-to-severe TBI (msTBI) at 1-5 months postinjury, compared with well matched healthy control children. We assessed CC function through interhemispheric transfer time (IHTT) as measured using event-related potentials (ERPs), and related this to DWI measures of WM integrity. Finally, the relation between DWI and IHTT results was supported by additional results of neurocognitive performance assessed using a single composite performance scale. Half of the msTBI participants (16 participants) had significantly slower IHTTs than the control group. This slow IHTT group demonstrated lower CC integrity (lower fractional anisotropy and higher mean diffusivity) and poorer neurocognitive functioning than both the control group and the msTBI group with normal IHTTs. Lower fractional anisotropy-a common sign of impaired WM-and slower IHTTs also predicted poor neurocognitive function. This study reveals that there is a subset of pediatric msTBI patients during the post-acute phase of injury who have markedly impaired CC functioning and structural integrity that is associated with poor neurocognitive functioning. ⋯ Traumatic brain injury (TBI) is the primary cause of death and disability in children and adolescents. There is considerable heterogeneity in postinjury outcome, which is only partially explained by injury severity. Imaging biomarkers may help explain some of this variance, as diffusion weighted imaging is sensitive to the white matter disruption that is common after injury. The corpus callosum (CC) is one of the most commonly reported areas of disruption. In this multimodal study, we discovered a divergence within our pediatric moderate-to-severe TBI sample 1-5 months postinjury. A subset of the TBI sample showed significant impairment in CC function, which is supported by additional results showing deficits in CC structural integrity. This subset also had poorer neurocognitive functioning. Our research sheds light on postinjury heterogeneity.
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Journal of neurotrauma · Jul 2015
Trends in Unintentional Fall Related Traumatic Brain Injury Death Rates in Older Adults in the United States, 1980-2010: A Joinpoint Analysis.
Unintentional fall-related traumatic brain injury (TBI) death rate is high in older adults in the United States, but little is known regarding trends of these death rates. We sought to examine unintentional fall-related TBI death rates by age and sex in older adults from 1980 through 2010 in the United States. We used multiple-cause mortality data from 1980 through 2010 (31 years of data) to identify fall-related TBI deaths. ⋯ The second joinpoint occurred in 2005 when the APC decreased to 3.8% for 2005-2010. This descriptive epidemiological study suggests increasing fall-related TBI death rates from 1992 to 2005 and then a slowdown of increasing trends between 2005 and 2010. Continued monitoring of fall-related TBI death rate trends is needed to determine the burden of this public health problem among older adults in the United States.