In 11 of 12 patients submitted to total intratemporal surgical exposure of the seventh nerve because of idiopathic facial paralysis, morphological changes were observed proximally to the geniculate ganglion in the beginning of the fallopian canal and in the internal auditory meatus. The presence of pathology proximally to the geniculate ganglion in cases of Bell's palsy has been supported by the intra-operative electric stimulation of the exposed facial nerve in cases presenting at surgery with neuropraxia as well as by the preoperative iophendylate (Pantopaque) cisternography and the results of the lacrimal test. More material has to be collected in order to substantiate the preliminary findings. The accumulated evidence indicates, however, that the most critical part of the intratemporal course of the seventh nerve in Bell's palsy is situated proximally to the geniculate ganglion rather than towards the stylomastoid foramen.
Ugo Fisch, Erlo Esslen. Total Intratemporal Exposure of the Facial NervePathologic Findings in Bell's Palsy. Arch Otolaryngol. 1972;95(4):335–341. doi:10.1001/archotol.1972.00770080529008