Quantitative MRI and 1H-MRS in Traumatic Brain Injury

轻度创伤性脑损伤(MTBI)和脑震荡后综合征(PCS)是公认的高度 重大公共卫生问题影响着120多万美国平民和战斗军人 这些行业每年的成本超过170亿美元。因此，令人不安的是，传统的临床 计算机断层扫描(CT)和磁共振成像(MRI)等放射学工具通常 未能检测到MTBI导致的大脑异常，这些异常可以解释一系列物理、认知和 定义PCS的情绪/行为症状。由于目前还没有良好的MTBI动物模型，目前 教导是，在人类，PCS的病理是弥漫性轴索损伤(DAI)主要发生的结果。 在灰白交界处、胼胝体和中脑等陈旧部位。与此相反的是 根据普遍接受的原则，我们假设(中心假说)在 MTBI是丘脑。这一假设是基于我们收集的初步结果。此数据 支持的依据是：(1)证明该结构的神经病理损伤的文献；以及(2) 将多种脑震荡后症状归因于一个部位。丘脑损伤导致结构性和 可通过MR(扩散峰度、磁场相关性、血液)量化的代谢异常 他还负责PCS检查)和磁共振波谱(MRS)。 为了检验这一假设，我们提出了三个具体目标：具体目标1：在第一个月内建立 MTBI后，在高场(3T)进行定量MR检查，发现显微结构、血流灌注和生化的证据 与年龄/性别匹配的对照组相比，每年有20名新患者出现丘脑异常。 具体目标2：将脑震荡后症状和一系列神经心理测试与 结构和生化指标。具体目标3：每年对每位患者进行连续随访，以使 MTBI临床结局定量预测指标的识别和验证。 与健康相关：这项研究旨在：(1)提高我们的诊断敏锐度和 对MTBI“流行病”的了解；(2)提供客观指标来检测和量化MTBI；(3) 能够预测结果；以及(4)为MTBI的病理生理学提供新的见解 这可能会为这些患者带来更好的治疗。

Mild traumatic brain injury (MTBI) and post concussion syndrome (PCS) are acknowledged as highly significant public health problems affecting over 1.2 million Americans in both civilian and combat military sectors at a cost exceeding $17 billion annually. Troubling, therefore, is the fact that conventional clinical radiological tools such as computed tomography (CT) and magnetic resonance (MR) imaging (MRI) often fail, to detect brain abnormalities ensuing from MTBI that can account for the array of physical, cognitive and emotional/behavioral symptoms defining PCS. Since there are no good animal models for MTBI, the current teaching is that in humans, PCS pathology is the result of diffuse axonal injury (DAI) occurring predominantly in stereotypical locations including the gray-white junction, corpus callosum, and midbrain. Contrary to this commonly accepted principle, we hypothesize (Central Hypothesis) that the primary site of injury in MTBI is the thalamus. This hypothesis is based upon the preliminary results we have gathered. This data is supported by: (1) literature demonstrating neuropathological injury to this structure; and (2) the ability to ascribe a multitude of post concussive symptoms to one site. Thalamic damage results in structural and metabolic abnormalities that can be quantified by MR (diffusion kurtosis, magnetic field correlation, blood perfusion, and volumetric measures) and MR spectroscopy (MRS) and is responsible for PCS. To test this hypothesis we propose three Specific Aims: Specific Aim 1: to establish, within the first month after MTBI, with quantitative MR at high-field (3T), evidence of microstructural, perfusional, and biochemical thalamic abnormalities, in 20 new patients accrued annually, compared with age/sex matched controls. Specific Aim 2: to associate post concussive symptoms and a battery of neuropsychological tests with structural and biochemical metrics. Specific Aim 3: to serially follow up each patient annually to enable identification and validation of quantitative predictive metrics of clinical outcome in MTBI. Health Relevance: This research is designed to: (1) improve our diagnostic acumen and understanding of the MTBI "epidemic"; (2) provide objective metrics to detect and quantify MTBI; (3) enable the prediction of outcome; and (4) contribute new insights into the pathophysiology of MTBI that will potentially result in better treatment for these patients.