Geniculate neuralgia and facial nerve sensory systems.

Although it is only a small ganglion, the geniculate ganglion subserves several different sensory systems with sensory fibers distributed to different parts of the head. The ganglion innervates chemoreceptors and phasic mechanoreceptors on the front of the tongue. In addition, the ganglion supplies mechanoreceptors of the hair follicles on the inner surface of the pinna and deep mechanoreceptors of nasal and buccal cavities. The ganglion also innervates chemoreceptors on the soft palate. No neurophysiological evidence was found for sensory innervation of the facial musculature. In considering neuralgias of geniculate ganglion origin, it is necessary to examine the loci of sensory projections of the ganglion and the possible effects of inflammation on pulse discharge patterns of sensory neurons.