Auditory tube

Auditory Tube

The auditory tube, also known as the Eustachian tube or pharyngotympanic tube, is a tube that links the middle ear to the nasopharynx, which is part of the upper throat and the back of the nasal cavity. It is named after the sixteenth-century anatomist Bartolomeo Eustachi who discovered it.

Function

The primary function of the auditory tube is to equalize the pressure in the middle ear with the pressure in the atmosphere. This is crucial for the proper functioning of the ear drum and the ossicles, the tiny bones in the middle ear that transmit sound vibrations to the inner ear. When the pressure in the middle ear and the outside environment is not equal, it can result in discomfort or pain, a condition known as barotrauma.

The auditory tube also drains mucus from the middle ear to the nasopharynx. This helps to prevent the buildup of fluid and bacteria in the middle ear, which can lead to otitis media, a common type of ear infection.

Structure

The auditory tube is approximately 35 to 38 millimeters in length and is made up of bone and cartilage. The portion closest to the middle ear is bony, while the part near the nasopharynx is cartilaginous. The tube is normally closed but opens when we swallow, yawn, or chew, allowing air to flow into or out of the middle ear.

Clinical significance

Problems with the auditory tube can lead to a number of health issues. If the tube becomes blocked, it can result in a buildup of fluid in the middle ear, leading to otitis media. This is particularly common in children, whose auditory tubes are shorter and more horizontal than those of adults.

Eustachian tube dysfunction is a condition where the tube does not open properly, leading to symptoms such as a feeling of fullness or pressure in the ear, hearing loss, and tinnitus, a ringing or buzzing noise in the ear.

See also

• Ear anatomy
• Otitis media
• Barotrauma
• Eustachian tube dysfunction