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

描述（由申请人提供）：多发性硬化症（MS）是年轻人中常见的神经系统残疾，仅在美国就有大约40万人受到影响。传统上认为它是一种白色疾病，但MRI评估白色物质异常与临床表现无关。最近的组织病理学研究表明，广泛的皮质灰质损害是存在于长期疾病的患者。因此，研究皮质病变在临床残疾和疾病进展中的作用已成为一个关键目标。然而，由于磁共振成像对皮质损伤的敏感性低，体内患者研究受到阻碍。新的和先进的磁共振成像技术提高了皮质病变检测，但只有一小部分皮质病变是可见的。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改善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色物质病变以及正常表现的皮质和白色物质的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特斯拉MRI序列。其次，我们将使用在第一个目标中开发的优化序列对患有长期疾病的MS患者以及年龄匹配的对照进行成像。将评估图像数据的整体视觉质量、组织信噪比和对比度噪声。目前，不存在皮质病变定位的金标准测量，因此与先前发表的组织病理学结果相当的病变计数率和分布将被视为MRI方法开发阶段的基准。 对患者的皮质脱髓鞘进行精确成像将是MS研究的一个突破。皮质病变成像将允许评估皮质对临床残疾和疾病进展的贡献，并可作为测量疾病负担和治疗疗效的替代标志物。

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.