Transcranial magnetic stimulation of the facial nerve: intraoperative study on the effect of stimulus parameters on the excitation site in man.
Transcranial magnetic stimulation of the facial nerve: intraoperative study on the effect of stimulus parameters on the excitation site in man.
复制标题
面神经经颅磁刺激：刺激参数对人体兴奋部位影响的术中研究。
DOI：
10.1002/mus.880150712
复制
发表时间：
1992
期刊：
影响因子：
3.4
通讯作者：
Schmid,J
中科院分区：
文献类型：
--
作者：
Schmid,UD;Moller,AR;Schmid,J
颅内面神经磁刺激 (magStim) 在临床和研究环境中进行，但激活部位存在争议。因此，将鼻肌对 magStim 的反应潜伏期与通过直接电刺激面神经根出口区 (REZ) 获得的反应潜伏期进行了比较。 (b) 面管孔处； (c) 在桥小脑角 (CPA) 的微血管减压手术期间位于茎乳窝。将刺激线圈放置在头皮顶枕区时获得的鼻肌反应潜伏期测量结果表明，位于 CPA 远端 5 至 16 毫米的面神经管迷路段被激活。这与文献中报道的物理模型研究一致，该研究表明：（a）靠近神经孔的磁场产生的电流强度特别高； (b) magStim 的激励最有可能发生在感应电场随距离快速变化的地方，即在高比电阻和低比电阻介质之间的解剖边界处。这些特征出现在面神经管迷路段的末端，面神经离开低电阻的脑脊液并进入高电阻的岩骨。神经兴奋部位稳健，不受大范围刺激强度和电流方向的影响，也不受线圈位置大变化的影响。这项研究的实际意义是，经颅 magStim 不能反映面神经管近端面神经段的神经传导，面神经管约占 REZ 和茎乳突窝之间神经长度的 40%。
Magnetic stimulation (magStim) of the intracranial facial nerve is performed in clinical and research settings, but the activation site is a matter of controversy. Latencies of nasalis muscle responses to magStim were, therefore, compared with those obtained by direct electrical stimulation of the facial nerve (a) at the root exit zone (REZ); (b) at the porus of the facial canal; and (c) in the stylomastoid fossa during microvascular decompression operations in the cerebellopontine angle (CPA). Measurements of latencies of the nasalis muscle response, obtained while the stimulating coil was placed over the parieto‐occipital area of the scalp, indicated that it was the labryinthine segment of the facial canal, 5 to 16 mm distal to the CPA, that was activated. This would be in agreement with studies of physical models reported in the literature that showed (a) the strength of the electrical current generated by a magnetic field is particularly high close to a nerve foramen; and (b) excitation to magStim is most likely to occur where the induced electrical field changes rapidly over distance, i.e., at anatomical boundaries between media of high and low specific resistance. These characteristics are found at the end of the labyrinthine segment of the facial canal, where the facial nerve leaves the low‐resistance cerebrospinal fluid and enters the high‐resistance petrous bone. The site of neural excitation is robust and unaffected by stimulus intensity and current direction within a wide range, or by large changes in location of the coil. The practical implication of this study is that transcranial magStim does not reflect nerve conduction in segments of the facial nerve that are located proximal to the facial canal, which accounts for about 40% of the nerve length between the REZ and the stylomastoid fossa.