Unified Shim-RF Coil Technology for Improved Whole-Brain Spectroscopic MRI for Neurological Disorders

项目总结/摘要 神经系统疾病影响全世界多达10亿人，并且是残疾的主要原因， 人类的苦难目前的护理成像标准（对比增强MRI）非常有限，无法检测到许多肿瘤。 神经和神经变性疾病。磁共振波谱成像（MRSI）具有很大的潜力， 补充常规临床MRI用于临床病症，包括脑肿瘤、新生儿和儿科 疾病（缺氧-缺血、遗传性代谢疾病和创伤性脑损伤），脱髓鞘疾病， 和感染性脑损伤钆造影剂清除不完全，重复使用 由于脑内积聚，对比增强成像最近收到了FDA的警告。MRSI不 使用造影剂，对患者无风险/风险极小。3D编码MRSI方法提供高灵敏度 每单位时间和单位体积。术前和放射治疗计划将大大受益于全3D 信息，理想情况下具有各向同性分辨率。基于回波平面光谱成像（EPSI）的3D全脑 MRSI已经在大多数扫描仪平台上使用，并且可能是最常用的快速MRSI技术 迄今3D MRSI的主要局限性是磁场B 0的不均匀性，这会加宽线形 并且降低了大约40%的大脑中的光谱质量（例如，内侧颞叶，下额叶皮层 内侧额回、脑干和小脑）。这限制了评估关键大脑区域的能力， 内侧颞叶（MTL）和眶额皮质（OFC），在神经系统疾病中具有关键作用。 最近，我们推出了一个全新的概念，称为统一线圈（UNIC），其中包括创新的 去耦方法，使单独的匀场和RF环路之间的距离为零毫米。RF和 匀场线圈非常接近目标器官，以最大化RF SNR和匀场。物理定律意味着 对局部非均匀场（如MTL/OFC）进行匀场的唯一有效方法是放置大小匹配的匀场 线圈，其产生相反的高阶场以抵消不均匀场。我们的假设是 UNIC将大大增加脑容量覆盖范围，并允许对整个大脑进行真正的代谢评估 使用3D MRSI。这将使更广泛的应用在患者管理与各种神经系统疾病。 拟议的研究将原型第一个UNIC头部线圈（目标1），优化匀场技术 性能和硬件复杂性（目标2），并定量评估该技术在改善大脑 3D MRSI的覆盖范围（目标3）。这项研究的成功完成将在很大程度上解决长期存在的B 0 全脑不均匀性问题。这样的线圈可以被广泛使用，以使整个MRSI社区受益， 先进的B 0匀场技术它将有助于促进MRSI的广泛临床接受。

Project Summary/Abstract Neurologic diseases affect as many as one billion people worldwide and are a major cause of disability and human suffering. Current standard of care imaging (contrast-enhanced MRI) is extremely limited to detect many neurological and neurodegenerative diseases. MR spectroscopic imaging (MRSI) has a great potential to supplement routine clinical MRI for clinical conditions including brain neoplasms, neonatal and pediatric disorders (hypoxia-ischemia, inherited metabolic diseases, and traumatic brain injury), demyelinating diseases, and infectious brain lesions. Gadolinium contrast agents have incomplete clearance, and repeated use of contrast-enhanced imaging has recently received an FDA warning due to brain accumulation. MRSI does not use contrast material and has no/minimal risk for patients. 3D encoded MRSI methods provide high sensitivity per unit time and unit volume. Presurgical and radiation treatment planning will greatly benefit from full 3D information, ideally with isotropic resolution. Echo-planar spectroscopic imaging (EPSI) based 3D whole-brain MRSI have been on most scanner platforms, and are probably the most commonly used fast MRSI techniques to date. The primary limitation of 3D MRSI has been magnetic B0 field inhomogeneity, which broadens lineshapes and diminishes spectral quality in about 40% of the brain (e.g., mesial temporal lobe, inferior frontal cortex, medial frontal gyrus, brainstem, and cerebellum). This limits the ability to evaluate critical brain regions such as mesial temporal lobe (MTL) and orbitofrontal cortex (OFC), which have pivotal roles across neurologic disorders. Recently, we introduced a radically novel concept called Unified Coil (UNIC), which includes innovative decoupling methods to bring the distance between separate shim and RF loops to zero millimeters. Both RF and shim coils are at a close proximity to the target organ for maximized RF SNR and shimming. Physical law implies that the only effective way to shim local inhomogeneous field (as in MTL/OFC) is by placing size-matched shim coils which generate opposite high-order field to counteract the inhomogeneous field. Our hypothesis is that UNIC will dramatically increase brain volume coverage and allow true metabolic evaluation of the entire brain using 3D MRSI. This will enable broader applications in patient management with various neurological disorders. The proposed study will prototype the first UNIC head coil (Aim 1), optimize the technique in shimming performance and hardware complexity (Aim 2), and assess the technique quantitatively in improving brain coverage of 3D MRSI (Aim 3). Successful completion of this study will largely resolve the longstanding B0 inhomogeneity issue in whole brain. Such coils can be widely used to benefit the entire MRSI community by advancing B0 shimming technology. It will help catalyze the widespread clinical acceptance of MRSI.