7T MRI of MS Cortical Lesions: Optimization of acquisition pulse sequences

描述(申请人提供)：多发性硬化症(MS)是一种年轻人常见的神经功能障碍，仅在美国就有大约40万人受到影响。它传统上被认为是一种白质疾病，但MRI对白质异常的评估与临床表现无关。最近的组织病理学研究表明，长期疾病患者存在广泛的皮质灰质损害。因此，研究皮质损伤在临床残疾和疾病进展中的作用已成为一个重要的目标。然而，由于磁共振成像对皮质损伤的敏感性较低，体内患者研究受到阻碍。新的和先进的磁共振成像技术改进了皮质病变的检测，但只有一小部分皮质病变可见。然而，很明显，超高磁场成像提供的高空间分辨率和图像对比度对于进一步提高皮质病变的可视化是必要的。在这项建议中，我们将追求两个目标。首先，我们将在7特斯拉下测量皮质和白质病变以及正常出现的皮质和白质的MRI组织参数。我们将在计算机模拟中使用这些参数来优化用于皮质病变成像的7个特斯拉MRI序列。其次，我们将用第一个目标中开发的优化序列对患有长期疾病的多发性硬化症患者以及年龄匹配的对照组进行成像。将评估图像数据的总体视觉质量、组织信噪比和对比度噪声。目前，还没有用于皮质病变定位的金标准，因此，在MRI方法开发阶段，与先前发表的组织病理学结果相当的病变计数比率和分布将被视为基准。患者皮质脱髓鞘的准确成像将构成多发性硬化症研究的突破。皮质病变成像将评估皮质对临床残疾和疾病进展的贡献，并可作为衡量疾病负担和治疗效果的替代标志物。 公共卫生相关性：多发性硬化症是一种毁灭性的中枢神经系统疾病。它同时影响灰质和白质，但对皮质灰质病变如何发展以及它们如何影响疾病进展知之甚少。我们建议改进超高场磁共振成像技术，以便更可靠地检测患者的皮质病变，并提高我们对这些病变形成机制的理解。

DESCRIPTION (provided by applicant): Multiple Sclerosis (MS) is a common neurological disability in young adults, affecting approximately 400,000 people in the United States alone. It is traditionally regarded as a white matter disease, but MRI assessment of white matter abnormalities does not correlate with clinical findings. Recent histopathologic studies suggest that extensive cortical gray matter damage is present in patients with longstanding disease. It has therefore become a critical goal to study the role of cortical lesions in clinical disability and disease progression. In vivo patient studies are, however, hampered by the low sensitivity of magnetic resonance imaging for cortical damage. New and advanced magnetic resonance imaging techniques have improved cortical lesion detection, but only a fraction of cortical lesions are visible. Nevertheless, it has become clear that the high spatial resolution and image contrast provided by ultra-high magnetic field imaging is necessary for further improvements in the visualization of cortical lesions. In this proposal, we will pursue two aims. First, we will measure MRI tissue parameters for cortical and white matter lesions and normal appearing cortex and white matter at 7 Tesla. We will use these parameters in computer simulations to optimize 7 Tesla MRI sequences for cortical lesion imaging. Secondly, we will image MS patients with longstanding disease as well as age-matched controls with the optimized sequences developed in the first goal. Image data will be assessed for their overall visual quality, tissue signal-to-noise, and contrast-to-noise. Currently, no gold standard measures for cortical lesion localization exist, thus lesion count rates and distributions comparable to previously published histopathologic findings will be considered the benchmark during the MRI method development phase. Accurate imaging of cortical demyelination in patients would constitute a breakthrough in MS research. Cortical lesion imaging will allow assessment of cortical contributions to clinical disability and disease progression, and may serve as a surrogate marker for measuring disease burden and treatment efficacy. PUBLIC HEALTH RELEVANCE: Multiple sclerosis is a devastating disease of the central nervous system. It affects both gray and white matter, however little is known about how cortical gray matter lesions develop and how they impact disease progrssion. We propose refining ultrahigh field magnetic resonance imaging technology in order to more reliably detect cortical lesions in patients, and improving our understanding of the mechanisms that drive the formation of these lesions.