Concurrent High-Speed fMRI and Diffusion Tensor MRSI

摘要/摘要 磁共振波谱成像(MRSI)、扩散张量成像(DTI)和功能磁共振成像的研究进展 (FMRI)有可能提高术前标测的临床实用性，以帮助诊断、治疗 脑肿瘤的计划和手术切除。扩散张量光谱成像(DTSi)可以提供 关于细胞内特性的独特信息，如粘度、细胞膨胀、亚细胞结构的限制、 和细胞质流动，这可能有助于表征渗透和炎症过程。DTSi 补体公司最近开发的组织水的Q空间轨迹成像(QTI)可以测量肿瘤 微观各向异性和各向同性非均质性的特殊异常在线性编码中看不到 扩散张量成像(DTI)。静息状态fmri(Rsfmri)是一种很有前途的无任务全脑成像方法。 补充基于任务的功能磁共振成像(TfMRI)，并将口才皮层的映射扩展到功能受损的患者。 评估这些先进的磁共振成像技术的个体和关节组织和功能特异性 它们在脑肿瘤患者的术前标测中的临床应用是相当有意义的。然而， DTSI与QTI和fMRI的集成受到DTSI较长的扫描时间和运动敏感性的阻碍，这 防止常规的临床使用。 该建议的主要目标是开发一种降低DTSi运动灵敏度的方法，该方法使用 单次激发编码，将DTSI和高速fMRI集成到单个脉冲序列中，以减少长扫描 在多模式术前标测中的时间，并在健康成人和患有 脑瘤。次要目标是评估DTSI和DSI的个体和联合敏感性和特异性。 用于组织表征的QTI。质子-回声-平面光谱成像的初步结果 (百事可乐)在3Tesla展示了(A)绘制代谢物扩散的年龄依赖关系图的可行性 儿童和成人，(B)术前使用高速功能磁共振成像和快速短TE 3D MRSI进行标测 脑肿瘤，以及(C)一次扫描同时进行fMRI和MRSI的概念验证。这样做的理由是 研究表明，多模式术前标测为提高敏感性提供了互补的生物标志物 以及与口才皮质相关的表征肿瘤组织状态和肿瘤边界的特异性， 补充手术决策和对功能和肿瘤结果的预测。 如果成功，这项研究将促进将先进的磁共振成像技术整合到临床脑成像方案中，以 研究新的组织特异性生物标志物及其与病理学的关系。

Summary/Abstract Recent advances in MR spectroscopic imaging (MRSI), diffusion tensor imaging (DTI) and functional MRI (fMRI) have the potential to enhance the clinical utility of presurgical mapping to aid in the diagnosis, treatment planning and surgical resection of brain neoplasms. Diffusion tensor spectroscopic imaging (DTSI) can provide unique information on intracellular properties, such as viscosity, cell swelling, restriction in subcellular structures, and cytoplasmic streaming that may help to characterize infiltration and inflammatory processes. DTSI complements recently developed Q-space trajectory imaging (QTI) of tissue water, which can measure tumor specific abnormalities in microscopic anisotropy and isotropic heterogeneity not seen in linearly encoded diffusion tensor imaging (DTI). Resting state fMRI (rsfMRI) is a promising task-free whole brain approach complementing task-based fMRI (tfMRI) and extending mapping of eloquent cortex to patients with impairment. Evaluating the individual and joint tissue and functional specificity of these advanced MRSI technologies and their clinical utility for presurgical mapping in patients with brain tumors is of considerable interest. However, integration of DTSI with QTI and fMRI is been hampered by long scan times and motion sensitivity of DTSI, which prevents routine clinical use. The primary objective of this proposal is to develop a method to reduce motion sensitivity of DTSI using single-shot encoding, to integrate DTSI and high-speed fMRI into a single pulse sequence to reduce long scan times in multi-modal presurgical mapping, and to validate this approach in healthy adults and in patients with brain tumors. A secondary objective is to assess the individual and joint sensitivity and specificity of DTSI and QTI for tissue characterization. Our preliminary results using Proton-Echo-Planar-Spectroscopic-Imaging (PEPSI) at 3 Tesla demonstrate (a) the feasibility of mapping the age dependence of metabolite diffusion in children and adults, (b) presurgical mapping with high-speed fMRI and fast short TE 3D MRSI in patients with brain tumors, and (c) proof-of-concept of simultaneous fMRI and MRSI in a single scan. The rationale of this research is that multi-modal presurgical mapping provides complementary biomarkers for improving sensitivity and specificity of characterizing tumor tissue status and tumor boundaries in relation to eloquent cortex, complementing surgical decision making and prediction of functional and oncological outcomes. If successful, this research will promote integration of advanced MRSI into clinical brain mapping protocols to study novel tissue-specific biomarkers and their association with pathology.