Corpus: Tympanic plexus

The tympanic plexus is an autonomic nerve network that spreads within the tympanic cavity through fine bony canals on the promontory of the tympanum.

The tympanic plexus receives sensory and preganglionic parasympathetic fibers from the tympanic nerve of the glossopharyngeal nerve (cranial nerve IX) and postganglionic sympathetic fibers from the carotid tympanic nerves, which originate from the internal carotid plexus.

The following nerves arise from the tympanic plexus:

• Lesser petrosal nerve: It travels to the otic ganglion.
• Communicating branch: It connects to the greater petrosal nerve.
• Tympanic branches: They provide sensory innervation to the mucous membrane of the tympanic cavity.
• Tubal branch: It supplies the auditory tube.