Characterization and Enhancement of Functional T1rho Imaging

项目摘要/摘要 最近的工作表明，功能性T1ρ为研究脑功能提供了一种新的成像技术。这 信号一直存在于人类和动物的视皮层研究中。这项技术已经被证明是 与通常用于使用磁共振成像评估大脑功能的血流动力学反应分开。首字母 研究表明，这种信号比使用ASL测量的动脉和静脉血管信号反应更快 和大胆的想象。此外，T1ρ信号已被证明对新陈代谢敏感 (葡萄糖、谷氨酸和pH)以及神经电流。最后，我们证明了功能T1ρ信号 对惊恐障碍的变化很敏感，使用大胆的成像并不明显，而且显示出脱钩 从双相情感障碍的大胆信号来看。这些发现突出了这一新功能的独特功能 成像技术，这可能为精神和神经疾病提供新的见解。然而，a 在我们目前对功能T1ρ信号的理解中存在许多空白，本提案旨在 地址。该项目的目标包括：1)确定功能性T1ρ反应和 在动物模型中使用植入生物传感器的局部代谢物和神经电流；2)增强空间 使用多波段和压缩传感的功能性T1ρ成像的覆盖范围和时间采样；3) 确定T1ρ相对于BOLD和ASL的时间和空间响应函数；以及4)评估 功能性T1ρ标测的稳定性、可靠性和准确性。作为这些具体目标的一部分，我们将评估 消除测量中的血管内信号并定义规范脉冲的技术 响应函数，可用于分析未来的功能性T1ρ成像研究。最后， 目标4中提出的可靠性分析将确定以下项目采用的功能T1ρ映射的能力 并将这项技术扩展到视觉皮质以外的范例。拟议的研究将允许 美国通过了解患者群体之间的功能变化的来源来解释 功能正常的T1ρ信号。对信号源的理解也将突出许多其他精神病学和 可以应用这种功能成像技术的神经性疾病。

PROJECT SUMMARY/ABSTRACT Recent work suggests that functional T1ρ provides a novel imaging technique to study brain function. This signal has been to exist in human and animal studies of the visual cortex. This technique has been shown to be separate from the hemodynamic response typically used to assess brain function using MR imaging. Initial work has shown that this signal responds faster than arterial and venous vascular signals measured using ASL and BOLD imaging respectively. In addition, the T1ρ signal has been shown to be sensitive to metabolism (glucose, glutamate, and pH) as well as neural currents. Finally, we have shown that the functional T1ρ signal was sensitive to changes in panic disorder not evident using BOLD imaging as well as shows a decoupling from the BOLD signal in bipolar disorder. These findings highlight the unique capabilities of this new functional imaging technique, which may provide new insight into psychiatric and neurological disorders. However, a number of gaps exist in our current understanding of the functional T1ρ signal, which this proposal aims to address. The aims of this project include: 1) Determine the relationship between functional T1ρ responses and local metabolites and neural currents using implanted biosensors in animal models; 2) Enhance spatial coverage and temporal sampling of functional T1ρ imaging using multi-band and compressed-sensing; 3) Determine the temporal and spatial response functions of T1ρ relative to BOLD and ASL; and 4) Evaluate the stability, reliability, and accuracy of functional T1ρ mapping. As part of these specific aims, we will evaluate techniques to eliminate the intravascular signal from the measurements and define a canonical impulse response function that can be used in the analysis of future functional T1ρ imaging studies. Finally, the reliability analysis proposed in Aim 4 will determine the ability of functional T1ρ mapping to be adopted by other groups and extend the technique to paradigms outside of the visual cortex. The proposed study will allow us to interpret the functional changes between patient populations by understanding the source of the functional T1ρ signal. The understanding of the signal source will also highlight many other psychiatric and neurological disorders where this functional imaging technique can be applied.