Ohkubo Harunobu, Komori Hiromichi, Kawabata Shigenori, Fukuoka Yuko, Shinomiya Kenichi
The Section of Orthopaedic Spinal Surgery, Department of Frontier Surgical Therapeutics, Division of Advanced Therapeutical Sciences Graduate School, Tokyo Medical and Dental University, Japan.
J Med Dent Sci. 2003 Jun;50(2):177-82.
Spinal cord evoked potentials (SCEPs) measurement is widely used for level diagnosis of spondylotic myelopathy. However, because of the restriction of spatial resolution, SCEPs do not distinguish the neurophysiological activities among tracts in the spinal cord without invasive methods. Magnetic field measurement has the theoretical advantage of high spatial resolution, compared with electric measurement. We recorded spinal cord evoked magnetic fields (SCEFs) in the thoracic spinal cord after stimulation to the motor area in felines, and estimated the source of the magnetic fields. SCEFs showed a quadrupolar pattern, and conducted in a cranial-to-caudal direction at 55 m/sec. According to this result, we estimated that the SCEFs after stimulation to the motor area were generated by the contralateral corticospinal tract. Furthermore, the estimated dipole of the SCEFs after stimulation to the motor area was located on the contralateral side in the spinal cord. These results correspond with the anatomical location of the corticospinal tract of felines, and suggest that magnetic field recording can detect the magnetic source localization of each tract in the spinal cord.
脊髓诱发电位（SCEPs）测量广泛用于脊髓型颈椎病的节段诊断。然而，由于空间分辨率的限制，在没有侵入性方法的情况下，SCEPs无法区分脊髓各传导束之间的神经生理活动。与电测量相比，磁场测量具有高空间分辨率的理论优势。我们在猫的运动区受到刺激后，记录了胸段脊髓的脊髓诱发磁场（SCEFs），并估计了磁场的来源。SCEFs呈现四极模式，并以55米/秒的速度从颅侧向尾侧传导。根据这一结果，我们估计运动区受到刺激后的SCEFs是由对侧皮质脊髓束产生的。此外，运动区受到刺激后的SCEFs估计偶极位于脊髓的对侧。这些结果与猫皮质脊髓束的解剖位置相符，并表明磁场记录可以检测脊髓中各传导束的磁源定位。
