Bezard E, Boraud T, Nguyen J P, Velasco F, Keravel Y, Gross C
Basal Gang, Laboratoire de Neurophysiologie, Université de Bordeaux II, France.
Neurosurgery. 1999 Aug;45(2):346-50. doi: 10.1097/00006123-199908000-00030.
The recent successful development of chronic stimulation of the motor cortex as a treatment for neuropathic and central pain does not exclude the possibility of eventual side effects, such as epileptic seizure or a lowering of the epileptic threshold. This study evaluates the behavioral and electroencephalographic impact of this treatment in three normal monkeys.
None of the monkeys presented epileptic behavior or abnormal electroencephalographic activity at parameters of stimulation currently used in clinical series, i.e., frequency and pulse duration of approximately 40 Hz and 90 microseconds, respectively, and an intensity just under the threshold for inducing muscle twitch in painful areas. Higher intensities did, however, induce reversible epileptic seizure. There was, nonetheless, no modification of the epileptic threshold, because even after these seizures, intermittent light stimulation elicited no abnormal electroencephalographic activity.
It thus seems that motor cortex stimulation does not induce epileptic complications when the classic clinical criteria of stimulation are respected. Nevertheless, it would be wise to subject candidates for implantation to intermittent light stimulation before and after a period of stimulation to ascertain the innocuousness of the cortical stimulation.
运动皮层慢性刺激作为治疗神经性疼痛和中枢性疼痛的方法最近取得了成功，但这并不排除最终出现副作用的可能性，如癫痫发作或癫痫阈值降低。本研究评估了这种治疗方法对三只正常猴子的行为和脑电图的影响。
在临床系列中目前使用的刺激参数下，即频率约为40Hz、脉冲持续时间约为90微秒，且强度略低于在疼痛区域诱发肌肉抽搐的阈值时，没有一只猴子出现癫痫行为或异常脑电图活动。然而，更高的强度确实诱发了可逆性癫痫发作。尽管如此，癫痫阈值并没有改变，因为即使在这些发作之后，间歇性光刺激也没有引发异常脑电图活动。
因此，当遵循经典的临床刺激标准时，运动皮层刺激似乎不会诱发癫痫并发症。然而，明智的做法是在刺激前后对植入候选者进行间歇性光刺激，以确定皮层刺激的无害性。
