Develop Multiphoton Magnetic Resonance Imaging

摘要 磁共振成像（MRI）是一种不可缺少的非侵入性成像技术， 医学和基础研究。今天的MRI假设单光子激发。更具体地说，对于每个核 自旋，单个光子伴随能量状态之间的跃迁，其产生MRI信号。该光子 必须在拉莫尔频率附近共振这个项目的目标是探索和开发一个全新的类 利用多光子激发的MRI。也就是说，代替通常的单光子共振， 技术可以通过使用多个磁场来激发多光子共振以产生用于MRI信号 频率，其中没有一个接近拉莫尔频率。只有自旋所吸收的总能量 对应于拉莫尔频率。多光子MRI是一种全新的MRI成像方法。它介绍了新的 激发、编码、对比度生成和接收的灵活性。该项目将探索和发展 临床上可行的多光子MRI的基本硬件、脉冲序列、激励和接收技术。 如果成功，多光子MRI将为许多新的途径铺平道路，以产生新的MRI图像， 有益于人类健康。

Abstract Magnetic resonance imaging (MRI) is an indispensable non-invasive imaging technology for diagnostic medicine and basic research. Today’s MRI assumes single-photon excitation. More specifically, for each nuclear spin, a single photon accompanies the transition between energy states which creates MRI signal. This photon must resonate near the Larmor frequency. The goal of this project is to explore and develop an entire new class of MRI that utilizes multiphoton excitation. That is, instead of the usual single-photon resonance, the proposed technique can excite multiphoton resonances to generate signal for MRI by using multiple magnetic field frequencies, none of which are near the Larmor frequency. Only the total energy absorbed by a spin must correspond to the Larmor frequency. Multiphoton MRI is a radical new way to perform MRI. It introduces new flexibilities for excitation, encoding, contrast generation and reception. The project will explore and develop the essential hardware, pulse sequences, excitation and receiving techniques for clinically feasible multiphoton MRI. If successful, multiphoton MRI will pave the road for many new avenues to generate novel MRI images and benefit human health.