Plug-and-Play High-Order B0 Shimming for Reliable Temporal Lobe Epilepsy Magnetic Resonance Spectroscopic Imaging

摘要： 癫痫影响全球700万人，颞叶癫痫（TLE）是其最常见的形式。为 对于接受手术治疗的TLE患者，功能性神经影像学对定位至关重要 癫痫病灶，最大限度地保护未受影响的地区，并优化手术后的结果。先生 光谱成像（MRSI）是直接定位代谢物异常的有前景的方式， 癫痫病灶的神经递质到目前为止，多项临床研究已经证明， MRSI在TLE和其他神经系统疾病（如胶质母细胞瘤）术后结局中的价值， 脑外伤然而，MRSI图像的可靠性经常受到B 0场均匀性不足的影响， 大脑的某个区域。特别是，蝶窦中的空气和 颞叶（TL）导致局部B 0场失真，因此破坏了主要部分的频谱质量。 TL.尽管最先进的MRI扫描仪配备有B 0场校正能力（B 0匀场）， 只能校正缓慢变化的场，而不能校正组织/空气界面处的高阶场干扰。在 为了提供准确可靠的颞叶MRSI，一种可靠的高阶B 0匀场装置 能够适应临床工作流程的设备是非常需要的。在高阶B 0的市场上，选择有限 匀场装置现有的产品通常太重，太复杂，无法用于 常规临床设置。在这个建议中，我们提出了一个轻量级的高阶匀场线圈，提供可靠的 标准临床工作流程下的整个TL MRSI覆盖范围。采用表面匀场/射频线圈技术， 轻量化的线圈组件，以及优化的接口设计，即插即用的高阶B 0匀场线圈将 开发并集成到临床高场扫描仪中。该提案的终点将奠定 在高场临床扫描仪中实现临床高阶B 0均匀性的基础。这将有利于 最先进的MRSI用于颞叶癫痫和其他主要神经系统疾病的临床翻译。

Abstract: Epilepsy affects 7 million people globally, and the temporal lobe epilepsy (TLE) is its most common form. For TLE patients that are undergoing surgical treatment, functional neuroimaging is vitally important to localize epileptic focus, maximize the preservation of unaffected areas, and optimize post-surgical outcomes. MR spectroscopic imaging (MRSI) is a promising modality to directly localize abnormalities of metabolites and neurotransmitters in the epileptic focus. To date, multiple clinical studies have demonstrated the prognostic value of MRSI in post-surgical outcomes for TLE and other neurological disorders such as glioblastoma and brain trauma. However, the MRSI image reliability is often impaired by the insufficient B0 field homogeneity in a certain region of the brain. Particularly, the susceptibility mismatch between the air in the sphenoid sinus and temporal lobe(TL) leads to local B0 field distortion, hence disrupt the spectral quality in a major portion of the TL. Although state-of-the-art MRI scanners are equipped with B0 field correcting capability (B0 shimming), it can only correct for slow varying fields and not the higher-order field disturbance at the tissue/air interfaces. In order to provide accurate and reliable MRSI for the temporal lobe, a reliable high-order B0 shimming device that can fit into clinical workflow is highly desirable. There are limited options in the market of high-order B0 shimming devices. The available products are usually too heavy and too complicated to be adopted in a routine clinical setting. In this proposal, we propose a lightweight high-order shim coil that provides reliable whole TL MRSI coverage under standard clinical workflow. Adopting the surface shim/RF coil technology, lightweight coil components, and optimized interface design, a plug-and-play high-order B0 shim coil will be developed and integrated into a clinical high field scanner. The endpoints of this proposal will lay the foundation to enable clinical high-order B0 homogeneity in high field clinical scanners. This will facilitate the clinical translation of state-of-the-art MRSI for temporal lobe epilepsy and other major neurological diseases.