Tympanic nerve
The tympanic nerve is a branch of the glossopharyngeal nerve (cranial nerve IX) that plays a crucial role in the innervation of the middle ear. It is involved in the sensory supply to the tympanic cavity and contributes to the formation of the tympanic plexus.
Anatomy[edit]
The tympanic nerve arises from the glossopharyngeal nerve shortly after it exits the jugular foramen. It enters the middle ear through the tympanic canaliculus, a small canal in the petrous part of the temporal bone.
Tympanic Plexus[edit]
Within the middle ear, the tympanic nerve forms the tympanic plexus on the promontory of the cochlea. This plexus provides sensory innervation to the mucous membrane of the tympanic cavity, the mastoid air cells, and the auditory tube.
Lesser Petrosal Nerve[edit]
Fibers from the tympanic plexus converge to form the lesser petrosal nerve, which carries preganglionic parasympathetic fibers to the otic ganglion. These fibers are involved in the innervation of the parotid gland.
Function[edit]
The primary function of the tympanic nerve is to supply sensory innervation to the mucosa of the middle ear. It also plays a role in the parasympathetic innervation of the parotid gland via the lesser petrosal nerve.
Clinical Significance[edit]
Damage to the tympanic nerve can result in loss of sensation in the middle ear and may affect the function of the parotid gland. Conditions such as glossopharyngeal neuralgia can involve the tympanic nerve, leading to pain in the ear and throat.
Images[edit]
Related Pages[edit]
References[edit]
- Standring, S. (2020). Gray's Anatomy: The Anatomical Basis of Clinical Practice. 42nd Edition. Elsevier.
- Moore, K. L., Dalley, A. F., & Agur, A. M. R. (2018). Clinically Oriented Anatomy. 8th Edition. Wolters Kluwer.
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Tympanic nerve illustration from Gray's Anatomy
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Tympanic nerve pathway
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Updated diagram of the tympanic nerve
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Tympanic nerve and surrounding structures
