Initial lesions in Bell's palsy and Ramsay-Hunt syndrome.
CONCLUSIONS
The antidromic facial nerve response (AFNR) revealed that the initial lesion in both Bell's palsy and Hunt syndrome was mainly located around the geniculate ganglion within 1 week after onset of paralysis. The preoperative AFNR reflected the response near the initial lesion.


OBJECTIVE
To review the initial lesion in Bell's palsy and Ramsay-Hunt syndrome using intraoperative monitoring of the AFNR.


METHODS
15 patients, including 8 with Bell's palsy and 7 with Ramsay-Hunt syndrome, were checked for the AFNR before and during transmastoid decompression surgery within 1 week after onset of paralysis. The AFNR monitoring was performed at the posterosuperior part of the anulus tympanicus preoperatively and at 4 points of the facial nerve during surgery. The nerve conduction block sites were diagnosed by the AFNR waveform.


RESULTS
The monophasic wave revealing the block site was mainly observed at the geniculate ganglion in both diseases. The latencies of the preoperative responses corresponded to those recorded intraoperatively around the pyramidal segment of the facial nerve.
Nakatani
Hiroaki
H
Department of Otolaryngology, Kochi Medical School, Nankoku, Kochi, Japan. hnakatan@tcc.pref.tochigi.lg.jp
Yamakawa
Kazuhiro
K
Hamada
Masashi
M
Takeda
Taizo
T
Kakigi
Akinobu
A
Iwai
Mitsuru
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D020330:Bell Palsy / Q000503:physiopathology* / Q000601:surgery; D002648:Child; D019299:Decompression, Surgical; D004568:Electrodiagnosis; D005260:Female; D005830:Geniculate Ganglion / Q000503:physiopathology; D016697:Herpes Zoster Oticus / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D009410:Nerve Degeneration / Q000503:physiopathology; D009431:Neural Conduction