3-dimensional Analysis for Conduction Blocks of the Spinal Cord with Multi-channel Superconducting Quantum Interference Device.

与传统的电势测量相比，脊髓磁场测量具有高空间分辨率的理论优势。本研究的目的是利用超导量子干涉装置（SQUID）测量脊髓的磁场并检测脊髓的三维传导块。高灵敏度的SQUID被设计用于检测来自脊髓的精细磁场。为此研制了一种具有两个SQUID线圈的梯度仪系统。设计并制作了一个小型屏蔽室来拦截外部磁噪声，并在屏蔽室内放置了SQUID系统。手术台放在一个可移动的塑料架上。对猫的坐骨神经进行电刺激，并在胸腰椎处测量脊髓产生的诱发磁场。通过坐骨神经刺激，可以测量上腰椎的诱发磁场。利用SQUID测量磁场可以诊断脊髓的传导阻滞，为脊髓功能的分析提供了依据。

The magnetic filed measurement of the spinal cord has theoretical advantages of high spatial resolution compared with the conventional electric potential measurement. The purpose of this study was to measure the magnetic field of the spinal cord and to examine three-dimensional conduction blocks of the cord with superconduction quantum interference device (SQUID). The highly sensitive SQUID was designed for detection of the fine magnetic fields from the spinal cord. A gradiometer system with two SQUID coils was produced for the study. Also a small shield room was designed and produced to intercept outside magnetic noise and the SQUID system were placed within the shield room. An operation table was placed on a movable plastic gantry. The sciatic nerve of a cat was stimulated electrically and evoked magnetic fields produced in the spinal cord were measured at the thoracic and the lumbar spine. Evoked magnetic fields at the upper lumbar spine could be measured by sciatic nerve stimulation. The magnetic field measurement with the SQUID could diagnose the conduction blocks and was useful for the analysis of the spinal cord function.