The purpose of this study is to offer a basis for clinical application of the antidromically evoked facial nerve response to intratemporal facial nerve paralysis. Antidromically evoked responses were recorded from the facial nerves of thirty-nine healthy guinea pigs. Waveforms recorded from active electrodes placed on the geniculate ganglion or the horizontal segment were analyzed in regard to site of lesions. Lesions were modeled by applying 4% lidocaine solution on the facial nerve at various sites. The normally evoked triphasic wave became biphasic when the presumed lesion was closely central to the recording site. Monophasic waves were recorded when the lesions were at the recording site. The results of this study gives basis for clinical interpretation of antidromically evoked responses in cases of intratemporal facial paralysis.
