Electrophysiologic Investigation During Facial Motor Neuron Suppression in Patients With Hemifacial Spasm: Possible Pathophysiology of Hemifacial Spasm: A Pilot Study

• DOI: 10.5535/arm.2013.37.6.839
• Publication Date: 2014-01-13T05:40:20Z
• Authors: Soo In Choi; Min-Wook Kim; Dong Yoon Park; Ryoong Huh; Dae-Hyun Jang
• Keywords: Hemifacial spasm; Facial muscles; Pathophysiology; Supraorbital nerve

Objective To evaluate the pathophysiological mechanism of hemifacial spasm (HFS), we performed electrophysiological examinations, such as supraorbital nerve stimulation with orbicularis oris muscle recording and lateral spread tests, after suppressing patient's central nervous system by administering intravenous diazepam. Methods Six patients HFS were recruited. Supraorbital test performed, followed application 10 mg diazepam to achieve facial motor neuron suppression. Subsequently, repeated two experiments mentioned above at 20 minutes had received intravenously. Results Orbicularis responses observed in all tests. After injection, no response was one patient, latencies this evident a slowing tendency time remaining five patients. However, consistently test. Conclusion Our results suggest that ectopic excitation/ephaptic transmission contributes mechanisms HFS. This is because suppressed our Keywords: Hemifacial spasm, Pathophysiology, Electromyography, Blinking, Diazepam