Post-facial Palsy Synkinesis: Electrodiagnostic Study Investigation of Facial Motor Pathway by Electrical and Magnetic Stimulation in Post-facial Palsy Synkinesis

J Korean Assoc EMG Electrodiagn Med 2001;3(1):20-26.
Published online May 10, 2001.

Abstract

Objectives : We performed to evaluate electrophysiologic properties in post-facial palsy synkinesis (PFPS) and to compare the electrophysiologic properties of PFPS with those of normal side. Methods : Electrophysiologic recordings were made from 36 patients with post-facial palsy synkinesis (10 men and 26 women) in Bong Seng Hospital from August 1995 to June 1999 and MEP study was performed in 15 patients among of them. Results : 1) The mean latencies of MEP were 6.23 msec from the mentalis, 5.89 msec from the orbicularis oculi, and 5.79msec from the nasalis, respectively, and the mean latencies of CMAP were 4.21 msec from the mentalis, 4.11msec from the orbicularis oculi, and 4.17msec from the nasalis, respectively. 2) The mean amplitudes of MEP were 2.65 mV from the mentalis, 1.65 mV from the orbicularis oculi, and 1.58 mV from the nasalis, respectively, and the mean amplitudes of CMAP were 2.84 mV from the mentalis, 2.37 mV from the orbicularis oculi, and 2.04 mV from the nasalis, respectively. 3) The measured latencies of the AMR were 12.34 msec from the mentalis and 12.15 msec from orbicularis oculi, respectively. We calculated the latencies of the AMR using the latencies of the CMAP and those of the MEP to identify the origin of the MEP. The latencies of the calculated AMR were 9.01 msec from the mentalis and 9.18 msec from orbicularis oculi, respectively. Conclusion : Patients with PFPS showed significantly prolonged distal latency and decreased amplitude of CMAP and MEP on affected side compared to the normal side.

Key Words: Post-facial palsy synkinesis, Abnormal muscle response, Motor evoked potentials, Compound muscle action potentials