Regional Cerebral Metabolism in Blast-Induced Mild Traumatic Brain Injury

描述（由申请人提供）： 爆炸引起的创伤性脑损伤（TBI）是最近在阿富汗和伊拉克冲突中服役的军事人员的主要损伤。脑震荡后综合征伴持续性长期认知功能障碍的情况在轻度脑外伤后也经常发生，直接影响军人的健康和安全。结构性和/或功能性脑损伤的准确诊断、评估和预后是极其重要和迫切需要的。不幸的是，目前对轻度TBI的诊断和评估主要基于自我报告的病史、主观测量和临床发现。传统的结构成像研究，如CT或MRI在评估轻度TBI中的作用非常有限。最近，一些研究表明，正电子发射断层扫描（PET）是一个可靠的工具，用于检测局部脑代谢（RCM）的变化，在轻度TBI和有可能客观地评估功能障碍的轻度TBI。PET，由于其生化灵敏度和定量测量，已被发现能够检测到细微的变化，即使没有明显的结构变化的RCM。尽管PET在轻度TBI评估中具有很好的潜力，但由于异常结果模式的变化，部分原因是其他合并症，如创伤后应激障碍（PTSD），其在临床，神经行为和成像表现中引入了混淆结果，因此既往研究的结论有限。在这个项目中，我们将评估局部脑代谢的变化，患者谁持续脑震荡后综合征，由于爆炸引起的轻度TBI。将纳入PTSD患者以了解混杂结果。本研究将招募总共210名个体，每组70名（TBI; PTSD;健康对照）。我们将测量RCM并对所有个体进行标准神经心理学评估。将采用适当的统计分析比较不同组间的RCM和认知功能/神经行为结果。我们将确定RCM和神经行为结果之间是否存在任何相关性。本研究结果有助于我们了解创伤性脑损伤的病理生理变化，尤其是代谢变化。异常RCM结果的严重程度和范围将作为临床评估的客观指标，并可能用于轻度TBI的预后。

DESCRIPTION (provided by applicant): Blast-induced traumatic brain injury (TBI) is the leading injury among military personnel who were serving in recent conflicts in Afghanistan and Iraq. Post-concussive syndrome with persistent long term cognitive impairment frequently occurs even after mild TBI, which directly impacts the health and safety of service members. Accurate diagnosis, assessment, and prognosis of structural and/or functional brain injury are extremely important and urgently needed. Unfortunately, current diagnosis and assessment for mild TBI are mainly based on self reported history, subjective measures and clinical findings. Conventional structural imaging studies such as CT or MRI have a very limited role in evaluation of mild TBI. Recently, several studies have demonstrated that Positron Emission Tomography (PET) is a reliable tool for detection of regional cerebral metabolic (RCM) changes in mild-TBI and have potential to objectively assess the functional impairment of mild TBI. PET, due to its biochemical sensitivity and quantitative measurability, has been found being able to detect subtle changes in RCM even without apparent structural changes. Despite the promising potential of PET in mild TBI evaluation, conclusion from prior studies has been limited due to variability in pattern of abnormal findings, partly due to other comorbidities such as Post Traumatic Stress Disorder (PTSD) which introduce confounding findings in clinical, neurobehavioral, and imaging presentation. In this project we will evaluate the regional cerebral metabolism changes in patients who had sustained post-concussion syndrome due to blast-induced mild TBI. PTSD patients will be included to understand the confounding findings. A total number of 210 individuals will be recruited in this study with 70 in each group (TBI; PTSD; healthy control). We will measure RCM and conduct standard neuropsychological assessments for all individuals. Appropriate statistical analyses will be applied to compare RCM and cognitive function/neurobehavioral findings among different groups. We will determine whether there is any correlation between RCM and neurobehavioral findings. The result of this study will help us understand the pathophysiological changes, especially the metabolic changes of TBI. The severity and extent of abnormal RCM findings will serve as an objective measurement for clinical evaluation, and possibly prognosis of mild TBI.