Magnetic Resonance Elastography

我们正在开发在人脑中进行磁共振弹性成像的临床方案。众所周知，在某些疾病状态下，如急性中风，由于局部压力增加导致健康组织进一步受损，脑水肿显著改变脑组织的弹性特性。众所周知，磁共振成像（MRI）信号中的相位分量包含有关组织运动的信息。如果在组织中建立了已知频率的驻波模式，并与磁梯度同步，则有可能获得3-D波模式，然后可以将其倒置以获得组织的机械性能的3-D图。这样的方案可以有显著的诊断价值，除了中风的一些情况下。我们已经开发并测试了用于激发大脑振动的机械换能器，结果表明，这可以安全实现，并且患者的不适最小。我们目前正在开发IRB批准的人体实验方案的应用。

We are in the process of developing a clinical protocol for performing Magnetic Resonance Elastography in the human brain. It is known that in some disease states, such as acute stroke, brain edema changes the elastic properties of brain tissue significantly as a result of increased local pressure leading to further damage of healthy tissue. It is also known that the phase component in the Magnetic Resonance Imaging (MRI) signal contains information about tissue movement. If a standing vibration wave pattern of known frequency is established in the tissue and in synchrony with the magnetic gradients, it is possible to obtain the 3-D wave pattern, which may then be inverted to obtain a 3-D map of mechanical properties of the tissue. Such a protocol could have significant diagnostic value for a number of cases beyond that of stroke. We have already developed and tested the mechanical transducer that will be used to excite vibration in the brain and it was shown that this can be achieved safely and with minimal patient discomfort. We are currently developing the application of the IRB approved protocol using human subjects.