Question #532
Lesser petrosal nerve
The lesser petrosal nerve is a branch of the tympanic branch of the glossopharyngeal nerve. It arises from the tympanic plexus within the middle ear cavity and exits through its own hiatus – the lesser petrosal nerve hiatus, to enter the middle cranial fossa. From here it runs anteriorly across the floor of the middle cranial fossa before exiting through the foramen ovale to synapse at the otic ganglion.
The nerve carries parasympathetic fibres that originate from the inferior salivatory nucleus. From the otic ganglion post-ganglionic fibres pass to the parotid gland.
