Panych L P, Wada J A, Beddoes M P
Division of Neurological Sciences, University of British Columbia, Vancouver, Canada.
Electroencephalogr Clin Neurophysiol. 1989 Mar;72(3):268-76. doi: 10.1016/0013-4694(89)90252-6.
In long-term scalp EEG monitoring of epileptic patients it is virtually impossible, in the present state of the technology, to avoid movement-related artefacts. These often obscure EEG information about the location of the seizure focus. One important example of such artefact is EMG activity. Its removal or suppression is sometimes enough to make otherwise useless EEG traces readable. Different methods of filtering have been applied towards that end. We routinely use a 15 Hz setting on our polygraph in obtaining EEG seizure printouts. We have recently examined digital filters which attenuate EMG beyond what is possible with the 15 Hz filter. A concern has been that the filters are practical in that they run in real time on a simple microprocessor and cause a minimum of confusion between smoothed artefact and actual brain activity.
在对癫痫患者进行长期头皮脑电图监测时，就目前的技术水平而言，几乎不可能避免与运动相关的伪迹。这些伪迹常常会掩盖有关癫痫发作病灶位置的脑电图信息。此类伪迹的一个重要例子就是肌电活动。去除或抑制它有时足以使原本无用的脑电图痕迹变得可读。为此已应用了不同的滤波方法。我们在获取脑电图癫痫打印输出时，通常在多道生理记录仪上设置15赫兹的频率。我们最近研究了能比15赫兹滤波器更有效地衰减肌电的数字滤波器。人们一直担心的是，这些滤波器切实可行，因为它们能在简单的微处理器上实时运行，并且在平滑后的伪迹与实际脑活动之间造成的混淆最小。
