Department of Clinical Laboratory, National Epilepsy Center, Shizuoka Institute of Epilepsy and Neurological Disorders, Shizuoka, Japan.
J Clin Neurophysiol. 2009 Dec;26(6):414-21. doi: 10.1097/WNP.0b013e3181c298c9.
The aims of this study were to record high-frequency oscillations (HFOs) associated with somatosensory-evoked potentials from subdural electrodes and to investigate their generators and clinical significance. Six patients who underwent long-term subdural electrode monitoring were studied. Somatosensory-evoked potentials were recorded directly from the subdural electrode after stimulation of the median nerve. Bandpass filter was 10 to 10,000 Hz for conventional somatosensory-evoked potential and 500 to 10,000 Hz for HFO. Three types of HFO were recorded. The first component was early HFO (407-926 Hz), which occurred before N20 peak. The second component was late HFO (408-909 Hz), which occurred after N20 peak. In addition, a novel component was recorded with a range from 1,235 to 2,632 Hz, and this component was termed very HFO. Early and late HFOs were recorded from relatively wide areas centering around the primary motor and primary sensory areas, whereas very HFO was localized around the primary sensory areas. In this study, at least three components of HFO could be identified. Only very HFO was localized around primary sensory areas, suggesting a possibility that very HFO may provide an effective method of identifying the central sulcus.
本研究旨在记录来自硬脑膜下电极的体感诱发电位相关的高频振荡（HFO），并研究其产生源及其临床意义。研究了 6 名接受长期硬脑膜下电极监测的患者。在刺激正中神经后，直接从硬脑膜下电极记录体感诱发电位。常规体感诱发电位的带通滤波器为 10 至 10,000 Hz，HFO 的带通滤波器为 500 至 10,000 Hz。记录了三种类型的 HFO。第一部分是早期 HFO（407-926 Hz），发生在 N20 峰之前。第二部分是晚期 HFO（408-909 Hz），发生在 N20 峰之后。此外，记录到一个范围从 1,235 到 2,632 Hz 的新型组件，该组件被称为非常 HFO。早期和晚期 HFO 记录自以主要运动和主要感觉区域为中心的较宽区域，而非常 HFO 则定位在主要感觉区域周围。在这项研究中，可以识别至少三个 HFO 组件。只有非常 HFO 定位在主要感觉区域周围，这表明非常 HFO 可能提供一种有效识别中央沟的方法。
