Visualization of the electrical activity of the cauda equina using a magnetospinography system in healthy subjects

• Published in: Clinical neurophysiology Vol. 130; no. 1; pp. 1 - 11
• Main Authors: Ushio, Shuta, Hoshino, Yuko, Kawabata, Shigenori, Adachi, Yoshiaki, Sekihara, Kensuke, Sumiya, Satoshi, Ukegawa, Dai, Sakaki, Kyohei, Watanabe, Taishi, Hasegawa, Yuki, Okawa, Atsushi
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.01.2019
• Subjects: Cauda equina; Conduction velocity; Evoked magnetic field; Magnetospinography; Peroneal nerve; Visualization of neural activity; MSG; Peroneal nerve; Magnetospinography; Evoked magnetic field; SQUID; Cauda equina; Conduction velocity; CECT; DSSP; SNAP; CEAP; UGRENS; CV; Visualization of neural activity; CEAF; SN; SEP
• ISSN: 1388-2457; 1872-8952; 1872-8952
• DOI: 10.1016/j.clinph.2018.11.001

•Magnetospinography visualized the electrical activity in the cauda equina.•The conduction velocities were obtained from reconstructed currents in the cauda equina.•Magnetospinography is expected to become a noninvasive functional examination technique for lumbar disease. To establish a method to measure cauda equina action fields (CEAFs) and visualize the electrical activities of the cauda equina in a broadly aged group of healthy adults. Using a 124-channel magnetospinography (MSG) system with superconducting interference devices, the CEAFs of 43 healthy volunteers (22–64 years of age) were measured after stimulation of the peroneal nerve at the knee. Reconstructed currents were obtained from the CEAFs and superimposed on the X-ray image. Conduction velocities were also calculated from the waveform of the reconstructed currents. The reconstructed currents were successfully visualized. They flowed into the L5/S1 foramen about 8.25–8.95 ms after the stimulation and propagated cranially along the spinal canal. In 32 subjects (74%), the conduction velocities of the reconstructed currents in the cauda equina could be calculated from the peak latency at the L2–L5 level. MSG visualized the electrical activity of the cauda equina after peroneal nerve stimulation in healthy adults. In addition, the conduction velocities of the reconstructed currents in the cauda equina could be calculated, despite previously being difficult to measure. MSG has the potential to be a novel and noninvasive functional examination for lumbar spinal disease.