Holder D S, Gardner-Medwin A R
Department of Physiology, University College, London, UK.
Clin Phys Physiol Meas. 1988;9 Suppl A:111-9. doi: 10.1088/0143-0815/9/4a/019.
The applicability of applied potential tomography (APT) to imaging neuronal discharge and spreading depression in the brain has been assessed with single channel impedance measurements. Stimulation of frog sciatic nerve, rat cortex and human subjects produced no changes in impedance measured at 50 kHz greater than 0.02%, which suggests that APT systems currently in use could not image neuronal discharge in practice. Larger changes in impedance of about 40% during spreading depression could be reproducibly measured on rat cortex, and could be simulated by a mathematical model. The signal was attenuated but detectable when measured on the dura and outside the skull. Spreading depression could provide a useful model for the development of APT in the brain, which, if achievable, could lead to applications of clinical value in neurology and neurosurgery.
已通过单通道阻抗测量评估了应用电位断层扫描（APT）在脑内神经元放电和扩散性抑制成像中的适用性。对青蛙坐骨神经、大鼠皮层和人类受试者进行刺激后，在50 kHz下测得的阻抗变化不超过0.02%，这表明目前使用的APT系统实际上无法对神经元放电进行成像。在大鼠皮层上可重复测量到扩散性抑制期间约40%的较大阻抗变化，并且可以用数学模型进行模拟。当在硬脑膜和颅骨外进行测量时，信号会衰减但仍可检测到。扩散性抑制可为脑内APT的发展提供一个有用的模型，如果能够实现，可能会在神经病学和神经外科领域带来具有临床价值的应用。
