Bodurka J, Jesmanowicz A, Hyde J S, Xu H, Estkowski L, Li S J
Biophysics Research Institute, Medical College of Wisconsin, Milwaukee, Wisconsin, 53226, USA.
J Magn Reson. 1999 Mar;137(1):265-71. doi: 10.1006/jmre.1998.1680.
Electric current-induced phase alternations have been imaged by fast magnetic resonance image (MRI) technology. We measured the magnetic resonance phase images induced by pulsed current stimulation from a phantom and detected its sensitivity. The pulsed current-induced phase image demonstrated the feasibility to detect phase changes of the proton magnetic resonance signal that could mimic neuronal firing. At the present experimental setting, a magnetic field strength change of 1.7 +/- 0.3 nT can be detected. We also calculated the averaged value of the magnetic flux density BT parallel to B0 produced by electric current I inside the voxel as a function of the wire position. The results of the calculation were consistent with our observation that for the same experimental setting the current-induced phase change could vary with location of the wire inside the voxel. We discuss our findings in terms of possible direct MRI detection of neuronal activity.
电流诱导的相位交替已通过快速磁共振成像（MRI）技术进行成像。我们测量了来自体模的脉冲电流刺激所诱导的磁共振相位图像，并检测了其灵敏度。脉冲电流诱导的相位图像证明了检测质子磁共振信号相位变化的可行性，该变化可模拟神经元放电。在当前的实验设置下，可检测到1.7±0.3 nT的磁场强度变化。我们还计算了体素内由电流I产生的平行于B0的磁通密度BT的平均值作为导线位置的函数。计算结果与我们的观察结果一致，即在相同的实验设置下，电流诱导的相位变化会随体素内导线的位置而变化。我们从神经元活动的直接MRI检测可能性方面讨论了我们的发现。
