EUSTACHIAN TUBE

EUSTACHIAN TUBE

Eustachian tube is a tube that connects the middle ear cavity to the nasopharynx. It plays a crucial role in equalizing the pressure in the middle ear and drainage of the mucus from the middle ear to the nasopharynx.

Parts of the auditory tube:

• Lateral wall: It has a cartilaginous part and a bony part.
• Cartilaginous part: It is made up of hyaline cartilage and is attached to the pharyngeal wall.
• Bony part: It is made up of thin plate of bone.
• Medial wall: It forms the posterior wall of the middle ear.
• Lumen: It is narrow and tortuous.

Relations of the auditory tube:

• It is situated between the nasopharynx and the middle ear cavity.
• It is related to the pharynx, the pterygopalatine fossa and the Eustachian cartilage.
• The cartilaginous part is related to the pharyngeal wall and the bony part is related to the sphenoid bone and the temporal bone.

Blood and nerve supply:

• Arterial supply: It is supplied by the pharyngeal branch of the maxillary artery and the ascending pharyngeal artery.
• Venous drainage: It drains into the pharyngeal venous plexus.
• Nerve supply: It is supplied by the pharyngeal branch of the trigeminal nerve (cranial nerve V) and the tympanic nerve (cranial nerve IX).

Clinical anatomy:

• It is an important structure for the drainage of the mucus from the middle ear to the nasopharynx.
• It is also involved in the equalization of the pressure in the middle ear.
• It is a common site for infections and is responsible for the development of otitis media.
• Dysfunction of the Eustachian tube can lead to various ear problems including hearing loss and tinnitus.