Nuclear magnetic resonance: in vivo proton chemical shift imaging. Work in progress.
Nuclear magnetic resonance: in vivo proton chemical shift imaging. Work in progress.
复制标题
核磁共振：体内质子化学位移成像。
作者：
I. Pykett;B. Rosen
利用三维傅里叶变换方法，首次获得了活体质子核磁共振化学位移图像。在61.5兆赫的质子共振频率下，简单模体的化学位移分辨图像表明，即使使用不是专门为化学位移光谱设计的磁体，也很容易在图像矩阵内的所有位置实现0.7ppm的光谱分辨率。人体前臂和猫头的活体图像可以从水和脂质子中分离出信号。然而，使用简单的射频脉冲序列，我们的数据显示，来自大脑中的膜脂(例如髓鞘)的信号相对较少。文中还给出了用该技术测量磁化率的方法。在帮助阐明复杂生物系统中核磁共振响应的起源的同时，该方法在医学诊断中也有潜在的应用。该技术也适用于其他原子核的化学位移成像，例如磷(P-31)。
Using a three-dimensional Fourier transform approach, proton nuclear magnetic resonance (NMR) chemical shift images have been obtained in vivo for the first time. At a proton resonance frequency of 61.5 MHz, chemical shift-resolved images of simple phantoms indicate that a spectral resolution of 0.7 parts per million (ppm) is readily achievable at all locations within the image matrix, even when using a magnet not specifically designed for chemical shift spectroscopy. In vivo images of the human forearm and of a cat head yield separable signals from water and lipid protons. However, using simple radiofrequency pulse sequences, our data show that relatively little signal originates from membrane lipids (e.g., myelin) in the brain. The measurement of magnetic susceptibility using this technique is also demonstrated. While helping to elucidate the genesis of the NMR response in complex biological systems, this methodology also has potential applications in medical diagnosis. The technique is also applicable to the chemical shift imaging of other nuclei; for example, phosphorus (P-31).