An fMRI Study of Deployment-Related TBI in Veterans and Service Members

描述（由申请人提供）： 项目背景：创伤性脑损伤（TBI）估计发生在10%至23%的持久自由行动/伊拉克自由行动/新黎明行动（OEF/OIF/OND）战斗人员中，导致认知，神经行为和情感后遗症和残疾。慢性期的诊断是困难的，因为传统的脑成像是不敏感的，急性损伤记录可能无法获得，创伤后应激障碍（PTSD）的症状往往与TBI重叠。TBI的高级脑成像可能会在弥散张量成像（DTI）上识别白色（WM）束的破坏，在功能性磁共振成像（fMRI）期间执行认知任务时大脑激活的改变，以及从静息状态fMRI测量的功能连接（FC）的变化。基本原理：我们报告说，TBI指数的DTI与增加在退伍军人的大脑激活，而他们执行的空间冲突解决（SPCR）的任务，我们和其他人的发现，由于WM损伤神经资源的需求增加。PTSD症状的严重程度对减少与任务相关的大脑激活有相反的影响。这项研究的局限性包括局限于爆炸性TBI，缺乏PTSD的明确诊断工具，以及我们的研究结果可能是特定于SPCR任务的。我们也没有评估静息状态FC。目的：研究轻度TBI（mTBI）的冲击波和非冲击波机制，增加可能对弥漫性WM损伤更敏感的复杂注意力的fMRI任务，测量默认模式网络（DMN）的FC，探索无mTBI病史的退伍军人中冲击波暴露的影响，并进行综合分析，以检查多模态脑成像与结局指标的关系。该项目将确定WM束损伤（DTI），功能磁共振成像在SPCR和注意力任务，在静息状态功能磁共振成像，功能，情感和认知状态之间的关系，在mTBI和非TBI组。研究方法：研究SPCR和复杂的注意力相关的脑激活在60 mTBI（e 3个月后受伤）和60非TBI没有爆炸暴露，以及20退伍军人和服务成员的历史爆炸暴露，但没有TBI。DTI将测量WM完整性，静息状态fMRI将测量FC。我们将评估认知、情感和功能结局以解决目标，并将使用临床医生辅助PTSD量表识别PTSD受试者。统计分析将整合多模态脑成像，以评估mTBI和PTSD对SPCR和注意力任务以及FC的脑激活的贡献。将分析与认知、情感和功能结果相关的一系列脑成像变量。与退伍军人医疗保健的相关性：改善慢性mTBI的诊断，包括没有TBI病史的爆炸暴露的影响，将有助于治疗计划并导致早期转诊。有关机制的信息也可能建议TBI和PTSD的干预方法，并提供评估治疗反应的方法。

DESCRIPTION (provided by applicant): Project Background: Traumatic brain injury (TBI) is estimated to have occurred in 10 to 23% of Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn (OEF/OIF/OND) combatants, resulting in cognitive, neurobehavioral, and emotional sequelae and disability. Diagnosis in the chronic phase is difficult because conventional brain imaging is insensitive, acute injury records may be unavailable, and symptoms of posttraumatic stress disorder (PTSD) often overlap with those of TBI. Advanced brain imaging of TBI could potentially identify disruption of white matter (WM) tracts on diffusion tensor imaging (DTI), alterations in brain activation while performing cognitive tasks during functional magnetic resonance imaging (fMRI), and changes in functional connectivity (FC) measured from resting state fMRI. Rationale: We reported that TBI indexed by DTI was related to increases in brain activation in Veterans while they performed a spatial conflict resolution (SPCR) task, a finding that we and others have attributed to increased demand upon neural resources due to WM injury. PTSD symptom severity had the opposite effect of reducing task-related brain activation. Limitations of this study included restriction to blast TBI, lack of a definitive diagnostic instrument for PTSD, and the possibility that our findings were specific to the SPCR task. We also did not evaluate resting state FC. Objectives: Study blast and non-blast mechanisms of mild TBI (mTBI), add an fMRI task of complex attention that is likely to be more sensitive to diffuse WM injury, measure FC of the default mode network (DMN), explore the effects of blast exposure in Veterans without a history of mTBI, and perform a comprehensive analysis to examine multi-modality brain imaging in relation to outcome measures. This project will determine relationships between WM tract injury (DTI), fMRI brain activation during SPCR and attention tasks, connectivity during resting state fMRI, and functional, emotional, and cognitive status in mTBI and non-TBI groups. Methods: Study SPCR and complex attention-related brain activation in 60 mTBI (e 3 months post-injury) and 60 non-TBI without blast exposure, as well as 20 Veterans and Service Members with a history of blast exposure but not TBI. DTI will measure WM integrity and resting state fMRI will provide a measure of FC. We will assess cognitive, emotional, and functional outcome to address the Aims and the Clinician Assisted PTSD Scale will be used to identify subjects with PTSD. Statistical analyses will integrate the multimodality brain imaging to evaluate the contributions of mTBI and PTSD to brain activation on the SPCR and attention tasks, as well as FC. The array of brain imaging variables will be analyzed in relation to cognitive, emotional, and functional outcome. Relevance to Veterans' Healthcare: Improved diagnosis of chronic mTBI, including effects of blast exposure without a history of TBI, would facilitate treatment planning and lead to earlier referral. Information about mechanisms may also suggest intervention approaches for TBI and PTSD and provide methods for assessing treatment response.