Magnetic Resonance Imaging in Facial Nerve Palsy: Comparison between Bell's Palsy and Herpes Zoster Oticus

Park, Shi Nae; Kim, Hyun Soo; Jung, So Lyung; Park, Kyung Ho; Kim, Bum Soo; Kwak, Bong Ki; Park, Jun Ook; Lee, Seok Eun; Yeo, Sang Won

Abstract

BACKGROUND AND OBJECTIVES
Magnetic resonance imaging (MRI) is a valuable and important tool for use in diagnosing and investigating diseases affecting the facial nerve. However, there are few reports investigating the difference in the MRI findings of Bell's palsy and Ramsay Hunt syndrome. in order to evaluate the difference in the clinical values regarding these two groups of facial nerve palsy syndrome. In this study, we observed the MRI findings to investigate the value of MRI and its clinical significance in those two different groups of facial nerve palsy. SUBJECTS AND METHOD: Fourty-eight patients of Bell's palsy or herpes zoster oticus, who were admitted to Kangnam St. Mary's Hospital from January 1998 to December 2003, were selected to assess the results of gadolinium enhanced MRI. The frequency and the site of the facial nerve enhancement and its correlation with electroneuronography (ENoG), the time interval of the palsy to MRI, and initial ESR levels were observed in both groups of facial nerve palsy. RESULTS: On gadolinium enhanced MRI, 16 of 24 patients with Bell's palsy and 22 of 24 patients with herpes zoster oticus had contrast enhancement in the meatal, labyrinthine segments and geniculate ganglion. The number of enhanced segments was significantly larger in the patients with herpes zoster oticus than in the patients with Bell's palsy (p<0.05). There has been significant correlation between the number of enhanced segment of the facial nerve and the result of ENoG in the patients with herpes zoster oticus (p<0.05). CONCLUSION: Gadolinium enhanced MRI (Gd-MRI) studies may predict the extent of lesion within the course of the facial nerve and its clinical value as a prognostic factor could be suggested in patients with herpes zoster oticus