Perman W H, Turski P A, Houston L W, Glover G H, Hayes C E
Radiology. 1986 Sep;160(3):811-20. doi: 10.1148/radiology.160.3.3737922.
The methodology of sodium-23 (Na-23) imaging is reported in relationship to the physiological factors that determine the chemical environment of the Na-23 nucleus. Contrast resolution is given as a function of imaging time and spatial resolution. Data showing the optimal relaxation time for sodium imaging are given, and the linear quantitative relationship between sodium concentration and voxel intensity for our imaging system is confirmed. The major problem facing in vivo sodium imaging is the ability to differentiate intracellular sodium from extracellular sodium. The sodium in blood serum (extracellular) and packed red blood cells (intracellular) both exhibit biexponential T2 decay. These results indicate that T2 measurements alone will be insufficient for discriminating extracellular from intracellular sodium. Instead, other methods based on the underlying physiological properties of in vivo sodium imaging, such as the diffusion coefficient, will be necessary to truly separate extracellular from intracellular sodium.
本文报道了钠-23（Na-23）成像方法与决定Na-23原子核化学环境的生理因素之间的关系。给出了对比分辨率与成像时间和空间分辨率的函数关系。给出了显示钠成像最佳弛豫时间的数据，并证实了我们成像系统中钠浓度与体素强度之间的线性定量关系。体内钠成像面临的主要问题是区分细胞内钠和细胞外钠的能力。血清（细胞外）和红细胞压积（细胞内）中的钠均表现出双指数T2衰减。这些结果表明，仅靠T2测量不足以区分细胞外钠和细胞内钠。相反，基于体内钠成像潜在生理特性的其他方法，如扩散系数，对于真正分离细胞外钠和细胞内钠将是必要的。
