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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
541

Third Ventricle Width as a Metric for Fast and Efficient Detection of Atrophy in Traumatic Brain Injury

Finuf, Christopher Scott 01 December 2015 (has links) (PDF)
In an average year more than 1.7 million people will experience a traumatic brain injury (TBI) in the United States. It is known that atrophy occurs across a spectrum for TBI patients, ranging from mild to severe. Current conventional magnetic resonance imaging (MRI) methods are inconsistent in detecting this atrophy on the milder end of the spectrum. Also more contemporary imaging tools, although efficient, are too time consuming for clinical applicability. It is for these reasons that a quick and efficient measurement for detecting this atrophy is needed by clinicians. The measuring of third ventricle width had the potential to be this measurement, since it is known that ventricular dilation is an indirect measure of brain atrophy. This study used two different data sets acquired at multiple sites. A total of 152 TBI patients' MRI scans were analyzed with diagnosis ranging from mild to severe. They have been age matched with 97 orthopedic injury controls. All scans were analyzed using Freesurfer® auto-segmentation software to acquire cortical, subcortical, and ventricular volumes. These metrics were then used as a standard of efficacy which we tested the new third ventricle width protocol against. There was no statistically significant difference between the overall TBI group and OI group (Welch's F(1,238.435) = 1.091, p= .267). The complicated mild injury subgroup was significantly increased from the mild subgroup (p= .001, d= .87). The grand average third ventricle width measurement was the best prognosticator of all measures analyzed despite only predicting 35.1% of cases correctly. The findings suggest that the third ventricle width measurement is insensitive to atrophy between all groups as hypothesized.
542

Mild Traumatic Brain Injury: Are Emergency Department Providers Identifying Which Patients Are At Risk?

Stuart, Barbara Kay 15 July 2010 (has links) (PDF)
Objective: Identify patients with specific emergency department (ED) discharge diagnoses who later report symptoms associated with a mild traumatic brain injury (MTBI), compare frequency and severity of MTBI symptoms by discharge diagnoses, investigate the frequency of head injury education provided to ED patients with each diagnosis, and finally, to learn what type of changes have occurred in the lives of patients as a result of their injury. Methods: Fifty-two ED patients, aged 18 to 28 who were at least two weeks post injury, spoke English and were discharged with a diagnosis of concussion/closed head injury (CHI), head laceration, motor vehicle crash (MVC), whiplash/cervical strain, facial/jaw fractures or multiple injuries were invited to participate. Participants completed the Post Concussive Symptom Scale (PCSS), a demographic questionnaire and then a series of open-ended questions about the impact the injury had on their lives. Results: MTBI symptoms on the PCSS were reported by 84.6% (n = 44) of respondents with a range of 1 – 23 different symptoms per participant. Headache (69.2%) and fatigue (61.5%) were the most common symptoms. Males (51% of the participants) reported on average 6.76 symptoms (S.D. = 6.53) whereas females reported an average of 12.68 symptoms (S.D. = 6.32). A large percentage (83.3%, n = 10) of participants with a MVC diagnosis reported severity scores in the moderate range (mean = 3.17; S. D. = 0.27) in all four PCSS categories (physical, thinking, sleep and emotional) representing the highest severity scores reported overall. Participants diagnosed with a concussion/CHI received the most (74%) head injury education of all discharge diagnoses, but only half (51%) received written information. The most common quality of life change was that 70.3% of survey participants became more cautious. Conclusion: Participants with a discharge diagnosis not commonly associated with brain injury reported having MTBI symptoms at least two weeks post injury with females reporting twice as many symptoms as males reported. Head injury education provided in the ED was lacking for all participants and although participants involved in a MVC reported having the most severe MTBI symptoms they had the least head injury education. All health care providers, especially nurses working in the ED, need to look beyond physical complaints and recognize injuries associated with increased risk for developing MTBI symptoms. Proactive ED identification of patients with "at risk" injuries by nurses would likely promote increased MTBI education and thereby result in fewer missed MTBI diagnoses.
543

The Neural Systems of Working Memory: The Sternberg Working Memory Task in a Pediatric Traumatic Brain Injury Sample

Pertab, Jon Leroy 29 April 2010 (has links) (PDF)
Working memory tasks are associated with the activation of widely distributed neural networks. The Sternberg working memory task has been used to explore the neural correlates associated with changes in memory load and the resolution of interference. Preliminary research suggests that the integrity of the anterior cingulate is correlated with resolving load adjustments but not in resolving interference demands; the opposite pattern of associations have been observed with the right middle frontal gyrus.Participants in the present study were 28 children who had sustained moderate to severe traumatic brain injuries (TBI) and 28 children who had sustained orthopedic injuries (OI). Participants were aged between 7 and 17 years at the time of injury (mean age = 13.2, s.d.=2.3). The groups were matched on age, gender, socioeconomic level, and pre-injury measures of behavioral and emotional functioning. Participants completed the Sternberg working memory task and structural MRI scans three months post injury. Automated brain parcellation software (Freesurfer) was used to calculate volumetric data for regions of interest. Regions of interest included the anterior cingulate and right middle frontal gyrus; additionally, the volume of the corpus callosum was used as an index of overall brain integrity. There were no significant differences between the groups on percent errors on the Sternberg task. Participants in the TBI group had significantly longer reaction times overall than the OI group. Interference in the Sternberg task has the potential to either help or hinder performance. Participants in the OI group displayed the anticipated effects of interference on reaction time whereas the TBI group as a whole did not display this pattern (priming effect not observed). The TBI group had significantly lower volumes in the regions of interest than the OI group. Hypothesized correlations between the regions of interest and changes in load / interference demands were partially supported. Exploratory analyses identified positive correlations between the volume of the right middle frontal gyrus and reaction time measures that warrant further exploration.
544

Imaging and Behavioral Correlates of the Anterior Cingulate in Pediatric Traumatic Brain Injury

Merkley, Tricia L. 25 February 2012 (has links) (PDF)
The anterior cingulate has been implicated in a number of cognitive processes that are at risk following traumatic brain injury (TBI), such as executive function and emotional processing. While the cingulate is believed to play a role in the above-mentioned cognitive processes, the relative roles of gray and white matter in functional outcomes post-TBI are not fully understood. The current study investigated various quantifiable brain properties (e.g., cortical thickness and volume, volume of underlying white matter, and white matter integrity) of the caudal anterior cingulate (CAC) gyrus and their relationships with behavioral measures of cognitive control following pediatric TBI. Parent ratings at three months post-injury indicated that TBI children demonstrated greater difficulty inhibiting inappropriate behavior and effectively transitioning between tasks. Reductions of CAC white matter integrity were observed in TBI participants, in the absence of significant morphometric group differences in this region. Neither CAC morphometrics nor fractional anisotropy (FA) were associated with experimental measures of cognitive control. The current findings indicate that DTI metrics may be more sensitive to brain changes in the region of the CAC following TBI. While strong relationships were not observed between CAC properties and measures of cognitive control, it is possible that study limitations may have obscured potential findings.
545

The Relationship Between Traumatic Brain Injury and Disruptions in Heart Rate Variability and Heart Rate Variability Biofeedback: A Systematic Review

Talbert, Leah D. 08 April 2022 (has links)
Background: Traumatic brain injury is a significant public health problem. Heart rate variability is a potential modality to measure physiological dysfunction following traumatic brain injury to assist in determining recovery time and the relationship between traumatic brain injury severity and recovery. To date, a summary of the evidence across injury severities and the possible role of heart rate variability biofeedback in traumatic brain injury treatment is lacking but needed to determine potential clinical utility. Participants and Methods: We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Systematic literature searches on CINAHL, Embase, PsycINFO, SPORTDiscus, and MEDLINE were conducted in August of 2020. There were two parts to this systematic review. Part I reviewed the relationship between heart rate variability and injury severity, recovery, and cognitive and emotional functioning. Part II reviewed the relationship between heart rate variability biofeedback and traumatic brain injury. Two coders coded each article and provided quality ratings with discrepancies resolved by consensus. Results: Regarding Part I, eighty-five papers met inclusion criteria. For outcome measures, eight studies (9%) focused on HRV as a predictor of mortality following moderate-to-severe traumatic brain injury; 9 studies (10%) included a measure of post-concussive symptom improvement; 7 studies (8%) included a measure of mood disturbance/change; 3 studies (3%) assessed return to consciousness. Overall, there appears to be a positive relationship between increased heart rate variability and recovery of clinical symptoms following traumatic brain injury. For Part II, seven papers met inclusion criteria. All studies included a measure of mood; 5 studies (71%) included neuropsychological functioning as an outcome measure; 1 study (14%) included a measure of life satisfaction. On average, participants completed 14 sessions of heart rate variability biofeedback (mean = 13.5, SD = 13.5, range = 1 to 40). Biofeedback was associated with improved heart rate variability following traumatic brain injury, though the methodological quality is questionable, and more controlled studies and randomized controlled trials are needed. Conclusions: Findings to date suggest a positive relationship between increased heart rate variability and recovery of clinical symptoms, including improvements in cognitive function and physical symptoms including headaches, dizziness, and sleep problems. Literature on traumatic brain injury and heart rate variability biofeedback treatment is in the early stages, and effectiveness is unclear due to poor-to-fair study quality, though early results are promising.
546

Animal-Assisted Green Care Farming for Patients with Traumatic Brain Injury

Sargsyan, Alex 20 April 2023 (has links)
Animal-Assisted Green Care Farming for Patients with Traumatic Brain Injury Purpose To examine the effects of Animal Assisted Therapies with Farm Animals (AATF) with domesticated ducks on depression and anxiety. Aim The proposed study will use single-group time series design and collect survey data to explore the changes in anxiety and depression in patients exposed to AATF. The study will be guided by the Self-Efficacy Theory. The study will involve 30 patients with TBI living in The Crumley House Rehabilitation Center in Limestone, TN. Hypothesis. Engaging in AATF with domesticated ducks will be associated with decrease in anxiety and depression. Approach - Theoretical Framework. Bandura’s Self-Efficacy Theory will be used to guide this study examining AATF effects on anxiety and depression in patients with TBI. Salutogenesis, Social Support, and Self-Efficacy theories were compared in order to select the best theoretical framework for this study. Methods Time series Quasi-experimental design. The study will examine the effects of AATF on anxiety and depression among patients with traumatic brain injury (TBI). Because of the unique characteristics of the patient population (all patients have history of TBI) in this facility no other rehabilitation center can be utilized for comparison. Time series design will ensure that all of the participants will be exposed to the therapeutic intervention, it will not be affected by the conventional treatments the participants are receiving. Projected Results and Anticipated Limitations It is expected that AATF will be effective in reduction of Anxiety and Depression symptoms in the patient with TBI Limitations • Possibility of dropouts may compromise sample size and lead to lower statistical power. • AATF based intervention is impossible to conduct in blinded environment. That in turn may contribute to participant’s expectation of positive outcomes of the interventions in this study. This may be considered an example of subject bias. • AATF treatment cannot be completely standardized. Because the treatment is based on interaction with live animals, animal behavior may be different during each visit to the duck pen. Because of that there is a possibility that the study cannot be exactly replicated. • The participants may have different duration or complexity of treatments for anxiety and depression. This may present a confounding factor that we are not able to control in this study. Conclusion This is a pilot study to examine the effects of AATF with domesticated ducks. This study may serve as a basis in developing more research on this topic with expanding the methodology and sampling in the future.
547

The effects of shockwaves on cultured mammalian neurons and their implications for mild traumatic brain injury

Ferenc, Matthew Teague January 2012 (has links)
Thesis (Ph.D.)--Boston University / The widespread use of Improvised Explosive Devices (IEDs) in the Wars in Iraq and Afghanistan has caused a dramatic increase in shockwave-induced mild Traumatic Brain Injury (mTBI), leading mTBI to be dubbed the 'signature injury' of modern warfare. Currently, the pathology of shockwave-induced mTBI is unknown , and it is diagnosis is based on self-reported symptoms and combat history. While the etiological mechanism has not yet been determined , it is becoming increasingly accepted that shockwaves themselves are the brain-damaging agent that emanate from IEDs. To assess how mild, sub-lethal shockwaves might damage brain tissue, we developed an in vitro assay to deliver shockwaves to neuronal cells in culture, and then assayed several properties of these cells that affect their function. This assay involved exposing rat cortical and hippocampal primary neuronal cultures to shockwaves of increasing magnitude generated with a biolistic Gene Gun. The Gene Gun produces shockwaves of sufficient overpressure to cause cognitive impairment in animal models of shockwave-induced mTBI. Our results show that overpressures of ~1.0 pound per square inch (psi) caused transient membrane permeability for molecules up to ~12 nanometers in diameter. This change in membrane permeability was accompanied by a transient decrease in cellular ATP levels and synaptic densities. This synaptic degeneration correlated with changes in the level and phosphorylation state of several synaptic proteins examined. Similar results were observed in dissected rat retinas suggesting that these shockwave-induced effects can occur in complex tissues, such as the brain. Based on these findings we propose that shockwaves damage cellular membranes, leading to a decrease in intracellular ATP, and ultimately to a reduced numbers of synapses, the part of neurons most important for learning, memory and behavior. Additional experiments in whole animals will be required to ascertain whether shockwave-induced cellular damage and synaptic degeneration plays an etiological role in shockwave-induced mTBI.
548

Traumatic Brain Injury Surveillance and Research with Electronic Health Records: Building New Capacities

McFarlane, Timothy D. 03 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Between 3.2 and 5.3 million U.S. civilians live with traumatic brain injury (TBI)-related disabilities. Although the post-acute phase of TBI has been recognized as both a discrete disease process and risk factor for chronic conditions, TBI is not recognized as a chronic disease. TBI epidemiology draws upon untimely, incomplete, cross-sectional, administrative datasets. The adoption of electronic health records (EHR) may supplement traditional datasets for public health surveillance and research. Methods Indiana constructed a state-wide clinical TBI registry from longitudinal (2004-2018) EHRs. This dissertation includes three distinct studies to enhance, evaluate, and apply the registry: 1) development and evaluation of a natural language processing algorithm for identification of TBI severity within free-text notes; 2) evaluation and comparison of the performance of the ICD-9-CM and ICD-10-CM surveillance definitions; and 3) estimating the effect of mild TBI (mTBI) on the risk of post-acute chronic conditions compared to individuals without mTBI. Results Automated extraction of Glasgow Coma Scale from clinical notes was feasible and demonstrated balanced recall and precision (F-scores) for classification of mild (99.8%), moderate (100%), and severe (99.9%) TBI. We observed poor sensitivity for ICD-10-CM TBI surveillance compared to ICD-9-CM (0.212 and 0.601, respectively), resulting in potentially 5-fold underreporting. ICD-10-CM was not statistically equivalent to ICD-9-CM for sensitivity (𝑑𝑑𝑑𝑑̂=0.389, 95% CI [0.388,0.405]) or positive predictive value (𝑑𝑑𝑑𝑑̂=-0.353, 95% CI [-0.362,-0.344]). Compared to a matched cohort, individuals with mTBI were more likely to be diagnosed with mental health, substance use, neurological, cardiovascular, and endocrine conditions. Conclusion ICD-9-CM and ICD-10-CM surveillance definitions were not equivalent, and the transition resulted in a underreporting incidence for mTBI. This has direct implications on existing and future TBI registries and the Report to Congress on Traumatic Brain Injury in the United States. The supplementation of state-based trauma registries with structured and unstructured EHR data is effective for studying TBI outcomes. Our findings support the classification of TBI as a chronic disease by funding bodies, which may improve public funding to replace legacy systems to improve standardization, timeliness, and completeness of the epidemiology and post-acute outcomes of TBI.
549

FE-Modelling and Material Characterization of Ice-Hockey Helmet

Rigoni, Isotta January 2017 (has links)
The aim of this research was to produce a reliable finite element model of a helmet, that could be used to simulate approval tests as well as impacts to investigate the safety offered. A 2D and 3D mesh was generated from the CAD file of an Easton Synergy 380 with HyperWorks, and then checked referring to standard parameter values. A few specimens cut from the liner were tested with the Instron Electropuls E3000 (Instron, High Wycombe, Great Britain) machine to determine Young’s modulus, Poisson’s ratio and the density of the EPP. The numerical model was characterised with appropriate materials with Ls-PrePost, such as ABS for the shell, EPP for the liner and steel for the impact anvil. The foam was implemented both with the *063_CRUSHABLE_FOAM and the *126_MODIFIED_HONEYCOMB card, in two different configurations. The helmet model was coupled with a finite element model of a HIII head form and three impact scenarios were set up. Backward, lateral and pitched impact were simulated and results were compared with those obtained from the experimental tests carried on at the MIPS. The two configurations were tested in all the three scenarios. The correlation between numerical and experimental results was evaluated by analysing the linear and rotational acceleration, and the rotational velocity, recorded by the accelerometer positioned inside the HIII headform. The parameters used were the Pearson correlation coefficient, the peak linear acceleration score, the shape of the curves, the time occurrence of peaks and the percentage of the difference between them. The first configuration showed good correlation scores (>85%) for the backward and lateral impact, for the rotational velocity and acceleration, while lower values were recorded for the pitched impact simulation. Lower values (70.88% and 77.76%) were obtained for the peak linear acceleration score, which stress the need for modifications of the contact definition in Ls-PrePost or a more detailed material testing. Worse results were recorded for the second configuration, but the smaller computational time required suggests that more attempts should be done in this direction.
550

Persons With Histories of Traumatic Brain Injury and Problematic Sexual Behavior: An Exploratory Analysis

LeMay, Carrie C., Stinson, Jill D. 29 December 2021 (has links)
Persons with traumatic brain injuries (TBI) who have engaged in problematic or illegal sexual behavior present with complex assessment and intervention needs yet remain understudied within the empirical literature. In the current exploratory analysis, important differences in adaptive and clinical functioning, adverse childhood experiences, and criminal offense history are examined in 25 persons with previous brain injury, 118 persons with intellectual disability but no known TBI, and 103 persons with no history of brain injury or intellectual disability, all of whom have engaged in problematic sexual behavior and who were residing in secure forensic inpatient care. Group differences were examined using comparisons of means and chi-squares. Results highlight important differences in education and employment experiences, diagnostic presentation, exposure to childhood maltreatment, and justice system involvement and characteristics of their sexual offense victims. Associations with prior literature and future research directions are discussed.

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