A Cinical and a fundamental study of the efficacy and the safety of Transcraniol Magnetic Stimmulation on facial movement disorders.

为了对周围性面瘫患者进行早期预后诊断，我们使用磁刺激器（Dantec Mag 2）直接刺激15名正常人和108名周围性面瘫患者的面神经颅内部分。对正常人和面瘫患者经颅磁刺激引起的口轮匝肌复合肌动作电位（CMAPs）与经颅磁刺激引起的茎突乳突孔外周肌复合肌动作电位（CMAPs）进行比较，后者与神经电图（ENoG）类似，在我科常用。正常受试者磁诱发cmap潜伏期（1.0 ms, SD 0.39 ms）比电刺激cmap潜伏期长。在患者中，ENoG值在麻痹发作后第7天下降，然后趋于平稳。然而，在发病后第7天，患侧与正常侧的磁诱发cmap振幅比没有下降的趋势。因此，磁诱发cmap能否被记录必须与面瘫的预后相关讨论。将发病后第7天内能记录到磁诱发cmap的患者分为ENoG最小值大于20%组。这些患者在麻痹发作后2个月左右恢复，明显优于未记录磁诱发CMAPs的患者。面神经受磁刺激的部位仍有争议。观察外周性面瘫患者的镫骨反射、瞬目反射和磁诱发cmap的恢复情况，探讨磁刺激部位。从临床角度看，面神经在颅金属孔附近受到磁刺激，这被认为是贝尔麻痹的损伤部位。这个刺激点与正常对照的磁诱发cmap和ENoG的平均潜伏期差计算出的点几乎相同。磁刺激试验未见有害影响。因此，证明了该试验的有效性。少

For an early prognostic diagnosis of patients with peripheral facial palsy, a magnetic stimulator (Dantec Mag 2) was used to directly stimulate the intracranial portion of the facial nerve in 15 normal subjects and 108 patients with peripheral facial palsy.In normal subjects and patients with facial palsy, compound muscle action potentials (CMAPs) of the orbicularis oris muscle elicited by transcranial magnetic stimulation were compared with CMAPs elicited by electrical stimulation at the peripheral site of the stylomastoid foramen which is similar to electroneurography (ENoG) and regularly used in our department. In normal subjects, the latency of magnetically evoked CMAPs was longer (1.0 ms, SD 0.39 ms) than that of CMAPs evoked by electrical stimulation.In patients, ENoG Values declined until the seventh day after onset of palsy, and then plateaued. However, the amplitude ratio of maganetically evoked CMAPs between the affected side and normal side showed no tendency to decline unti … More l the seventh day after onset of palsy. So, whether magnetically evoked CMAPs could be recorded must be discussed in relation to the prognosis for facial palsy. The patients whom magnetically evoked CMAPs could be recorded within the seventh day after onset of palsy were classified in a group in which the minimal ENoG value was greater than 20%. Those patients recovered almost 2 months after the onset of palsy, and were significantly better than their recovery rates those of the patients in whom magnetically evoked CMAPs could not be recorded.The site at which the facial nerve is magnetically stimulated remains controversial. In patients whth peripheral facial palsy, recovery of stapedial reflex, blink reflex and magnetically evoked CMAPs were examined to investigate the site of magnetic stimulation. From the clinical perspective, the facial nerve is thought to be magnetically stimulated near the meatal foramen which is thought to be the damage site in Bell's palsy. This stimulation site was almost the same point as that calculated from the mean latency difference between magnetically evoked CMAPs and ENoG in normal controls.No harmful effects were seen during the magnetic stimulation test. Accordingly, the efficacy of this test was demonstrated. Less