Comparison of Transcranial Magnetic Stimulation and Electroneuronography Between Bell's Palsy and Ramsay Hunt Syndrome in Their Acute Stages

• Published in: Annals of rehabilitation medicine Vol. 37; no. 1; pp. 103 - 109
• Main Authors: Hur, Dong Min, Kim, Seong Hoon, Lee, Young Hee, Kim, Sung Hoon, Park, Jung Mi, Kim, Ji Hyun, Yong, Sang Yeol, Shinn, Jong Mock, Oh, Kyung Joon
• Format: Journal Article
• Language: English
• Published: Korea (South) Korean Academy of Rehabilitation Medicine 01.02.2013; 대한재활의학회
• Subjects: Original; 재활의학; Herpes zoster oticus; Prognosis; Transcranial magnetic stimulation; Bell palsy
• ISSN: 2234-0645; 2234-0653
• DOI: 10.5535/arm.2013.37.1.103

To examine the neurophysiologic status in patients with idiopathic facial nerve palsy (Bell's palsy) and Ramsay Hunt syndrome (herpes zoster oticus) within 7 days from onset of symptoms, by comparing the amplitude of compound muscle action potentials (CMAP) of facial muscles in electroneuronography (ENoG) and transcranial magnetic stimulation (TMS). The facial nerve conduction study using ENoG and TMS was performed in 42 patients with Bell's palsy and 14 patients with Ramsay Hunt syndrome within 7 days from onset of symptoms. Denervation ratio was calculated as CMAP amplitude evoked by ENoG or TMS on the affected side as percentage of the amplitudes on the healthy side. The severity of the facial palsy was graded according to House-Brackmann facial grading scale (H-B FGS). In all subjects, the denervation ratio in TMS (71.53±18.38%) was significantly greater than the denervation ratio in ENoG (41.95±21.59%). The difference of denervation ratio between ENoG and TMS was significantly smaller in patients with Ramsay Hunt syndrome than in patients with Bell's palsy. The denervation ratio of ENoG or TMS did not correlated significantly with the H-B FGS. In the electrophysiologic study for evaluation in patients with facial palsy within 7 days from onset of symptoms, ENoG and TMS are useful in gaining additional information about the neurophysiologic status of the facial nerve and may help to evaluate prognosis and set management plan.