Neurology Department, Atatürk Training and Research Hospital, Izmir, Turkey.
Int J Neurosci. 2009;119(11):2044-55. doi: 10.1080/00207450903139705.
Lateral spreading and synkinetic responses of blink reflex are a sign of ephaptic transmission in idiopathic hemifacial spasm (HFS). The aim of this study was to evaluate the effect of botulinum toxin A (Btx A) on ephaptic transmission in idiopathic HFS.
Thirty-three patients with idiopathic HFS were investigated. Btx A was injected only into the affected orbicularis oculi (OC) muscle. Electrophysiological studies were performed before and three weeks after the Btx A injection.
After Btx A, the latencies of motor response and blink reflexes elicited from the OC muscle were significantly increased. The lateral spreading was not obtained in the OC muscle, while the orbicularis oris muscle response was not changed. There were no significant differences in the synkinetic responses of blink reflex. During needle EMG examination, positive sharp waves and fibrilation potentials were observed due to chemodenervation only in the OC muscle.
Btx A affects only the neuromuscular junctions of the injected muscle and has no effect upon ephaptic transmission.
眨眼反射的侧扩散和协同反应是特发性面肌痉挛（HFS）中电突触传递的标志。本研究旨在评估肉毒毒素 A（Btx A）对特发性 HFS 中电突触传递的影响。
研究了 33 例特发性 HFS 患者。Btx A 仅注射到受累的眼轮匝肌（OC）中。在 Btx A 注射前和注射后 3 周进行电生理研究。
Btx A 后，OC 肌肉诱发的运动反应和眨眼反射的潜伏期显著增加。OC 肌肉中未获得侧扩散，而口轮匝肌反应未改变。眨眼反射的协同反应无显著差异。在针 EMG 检查中，由于化学去神经支配，仅在 OC 肌肉中观察到阳性锐波和纤维颤搐电位。
Btx A 仅影响注射肌肉的神经肌肉接头，对电突触传递没有影响。
