Technical development of sodium magnetic resonance imaging of the human knee

在过去的25年里，硬件和软件在工程上的进步使得磁共振成像(MRI)在诊断和改善对许多人类疾病和障碍的理解方面不可或缺。常规的临床MRI测量来自水的氢核(即质子，1H)的信号，正是组织的水性质的独特差异产生了图像对比度。然而，通过适当的工程，核磁共振可以从不同的核获得信号，即体内自然丰富的钠离子(23Na)。钠与正常的细胞功能直接相关，尽管在常规MRI上表现正常，但钠可能提供组织损伤的证据。由于钠在组织中的低浓度和复杂的物理响应，钠的敏感性很低，因此MRI本身就具有很大的挑战性。因此，由于缺乏合适的电子学和专门的成像脉冲序列，钠MRI是一种非标准的成像技术，在大多数临床1.5T(即磁场强度)MRI扫描仪上是不可用的。如果核磁共振扫描仪有非常强的磁场，成像就会更敏感。这项提议将利用位于艾伯塔大学的非常强大的“三倍强度”核磁共振扫描仪(4.7T)。

Engineering advances of hardware and software over the last 25 years have made magnetic resonance imaging (MRI) indispensable for the diagnosis and improved understanding of many human diseases and disorders. Routine clinical MRI measures signal from the hydrogen nucleus (i.e. proton, 1H) of water and it is unique differences in the water properties of tissue that yields image contrast. However, with the appropriate engineering, MRI can acquire signal from a different nucleus, namely the naturally abundant sodium (23Na) ion within the body. Sodium is linked directly to proper cell function, and may provide evidence of tissue injury despite normal appearance on conventional MRI. Sodium MRI is inherently very challenging because of low sensitivity due to sodium's low concentration in tissue and complicated physics responses. Therefore, sodium MRI is a non-standard imaging technique not available on most clinical 1.5T (i.e. strength of the magnetic field) MRI scanners because of the lack of appropriate electronics and specialized imaging pulse sequences. Imaging is more sensitive if the MRI scanner has a very strong magnetic field. This proposal will take advantage of a very strong "triple strength" MRI scanner (4.7T) located at the University of Alberta.