经颅短串电刺激运动诱发电位的临床应用

The clinical application of MEP elicited by short train transcranial electrical stimulation

目的 探讨在常用麻醉方案下采用经颅短串电刺激技术获得运动诱发电位 (MEP) ,从而实现运动传导通路的术中监护的可行性。方法 随机选择华山医院神经外科自 2 0 0 2年 6月至 2 0 0 3年 1月共 4 0例无明显肢体肌力减退的手术患者 ,给予异丙酚全静脉麻醉 ,采用经颅短串电刺激技术(刺激参数 :30～ 10 0mA ;单个脉冲波宽 :10 0～ 5 0 0 μs;脉冲波间隔时间 :1.2 5～ 5ms ;每串所含脉冲波个数 :2～ 5个 /串 )诱发运动诱发电位 ,记录对侧上肢前臂屈肌群 ,拇短展肌和小指展肌所获电位的波幅和潜伏期 ,考察各刺激参数对所获电位的影响及其最佳组合。结果 在 94 .6 %的患者中 ,采用 80～10 0mA ,5 0 0 μs,2ms,4个 /串的刺激参数组合能获得波幅和潜伏期均满意的MEP。 结论 选用异丙酚全静脉麻醉 ,配合使用经颅短串电刺激技术可以获得MEP 。

Objective This was a prospective study of the methodology of motor evoked potential (MEP) elicited by short train transcranial electrical stimulation(ST-TES) under usual anesthetic conditions.Methods Multisegmental recordings of MEP of the upper extremities elicited by ST-TES technique (stimulus intensity: 30～100 mA, pulse duration: 100～500 μs, interstimulus interval: 1.25～5 ms, number of pulses per train: 2～5)were conducted on 40 patients without severe motor deficit. The major anesthetic agent was propofol, while muscle relaxant and analgetic were also used. The amplitude and the latency of MEP were compared between different stimulus parameter combinations.Results The combination of 80～100 mA, 500 μs, 2 ms and 4 pulses per train was a wise choice for most patients.Conclusion Satisfactory MEP can be achieved by using ST-TES technique together with the propofol anesthesia. Therefore the motor pathway may be monitored intraoperatively.