Department of Physical Therapy, Faculty of Health Sciences, Aomori University of Health and Welfare, 58-1 Mase, Hamadate, Aomori 030-8505, Japan.
Department of Respiratory and Nervous System Science, Biomedical Laboratory Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
Clin Neurophysiol. 2023 Jan;145:129-138. doi: 10.1016/j.clinph.2022.09.018. Epub 2022 Oct 10.
To visualize impulse conduction along the brachial plexus through simultaneous electromagnetic measurements.
Neuromagnetic fields following median nerve stimulation were recorded above the clavicle with a superconducting quantum interference device biomagnetometer system in 7 healthy volunteers. Compound nerve action potentials (CNAPs) were obtained from 12 locations. Pseudocolor maps of equivalent currents reconstructed from magnetic fields and isopotential contour maps were superimposed onto X-ray images. Surface potentials and current waveforms at virtual electrodes along the brachial plexus were compared.
In magnetic field analysis, the leading axonal current followed by a trailing backward current traveled rostrally along the brachial plexus. The spatial extent of the longitudinal intra-axonal currents corresponded to the extent of the positive-negative-positive potential field reflecting transmembrane volume currents. The peaks and troughs of the intra-axonal biphasic current waveforms coincided with the zero-crossings of triphasic CNAP waveforms. The amplitudes of CNAPs and current moments were linearly correlated.
Reconstructed neural activity in magnetic field analysis visualizes not only intra-axonal currents, but also transmembrane volume currents, which are in good agreement with the surface potential field.
Magnetoneurography is a novel non-invasive functional imaging modality for the brachial plexus whose performance can surpass that of electric potential measurement.
通过同时进行电磁测量来可视化臂丛神经的冲动传导。
在 7 名健康志愿者中，使用超导量子干涉器件生物磁强计系统，在锁骨上方记录正中神经刺激后的神经磁场。从 12 个部位获得复合神经动作电位 (CNAP)。从磁场重建的等效电流的伪彩色图和等电位等高线图被叠加到 X 射线图像上。比较臂丛神经沿线虚拟电极的表面电位和电流波形。
在磁场分析中，顺行轴突电流紧随其后的是逆行后电流，沿着臂丛神经向头侧传播。纵向轴内电流的空间范围与反映跨膜容积电流的正-负-正电位场的范围相对应。双相轴内电流波形的峰和谷与三相 CNAP 波形的零交叉点一致。CNAP 的幅度和电流矩呈线性相关。
磁场分析中重建的神经活动不仅可视化了轴内电流，还可视化了跨膜容积电流，这与表面电位场非常吻合。
磁神经图是一种用于臂丛神经的新型非侵入性功能成像方式，其性能可以超过电位测量。
