The Anatomy of the Eustachian Tube

The eustachian tube extends from the middle ear to the upper part of the throat behind the nose. Also known as the auditory tube, it helps keep the middle ear healthy by equalizing pressure, clearing secretions, and protecting it from pathogens that might otherwise cause infections.

Anatomy

Your eustachian tube is located in the area known as parapharyngeal space. It runs from the front wall of the middle ear to the side wall of the nasopharynx. In adults, the eustachian tube slopes downward about 35 degrees; in children, the eustachian tube only slopes about 10 degrees downward.

The eustachian tube consists of bone, cartilage, and fibrous tissue. The hollow tube is lined with cilia, hair-like projections that sweep mucus away from the middle ear toward the nasopharynx. 

Six muscles contribute to the opening and closing of the eustachian tube. They are located in the ear, head, neck, soft palate, and jaw.

Function

The eustachian tube has three roles in keeping the middle ear healthy. It:

• Keeps air pressure equal on both sides of the eardrum
• Drains secretions from the middle ear
• Protects the middle ear from bacteria and viruses

The eustachian tube is usually closed but opens periodically when muscles contract during actions like yawning and swallowing. When the air pressure changes outside, your eustachian tube opens to allow air to move from the ear canal to the middle ear so the pressure can equalize on both sides of the eardrum. 

To maintain proper functioning of the middle ear, the eustachian tube space needs to be free of fluid and other debris. The cilia and mucosal folds in the eustachian tube are thought to work together to actively drain mucus produced in the middle of the ear.

Most of the time, your eustachian tubes stay closed to protect the middle ear, effectively serving as barriers to protect the area from nasopharyngeal secretions and pathogens. 

Associated Conditions

Eustachian tube dysfunction (ETD) can occur when the tubes don’t open or close properly. When the eustachian tube has a blockage, it causes unequal pressure in the ear canal and middle ear. This can cause symptoms such as fullness in the ears, reduced hearing, and ear pain. The pressure can also cause vertigo, which is a problem with balance, and tinnitus, a ringing or buzzing in the ears. 

The eustachian tubes commonly become blocked because of nasal secretions from upper respiratory tract infections, allergies, or sinusitis. These secretions can also contain bacteria or viruses, which can cause a middle ear infection, also known as otitis media.

Some people have no trouble opening their eustachian tubes when air pressure changes, such as when flying in an airplane or diving underwater. Others may have a harder time, making it harder to equalize the pressure and causing some temporary ear pain.

Patulous eustachian tube, which is less common, results from the eustachian tube remaining open longer than usual. Patients may complain of feeling pressure in their ears or hearing a distortion in their own voice or breathing. In many cases, the cause of patulous eustachian tube is not known, but some of the risk factors include weight loss, pregnancy, neurologic disorders like multiple sclerosis, anxiety, and exhaustion.

Treatment

Most ETD symptoms are mild and resolve within a few days. If your eustachian tubes are blocked, you can try some simple methods to clear them, such as swallowing, chewing gum, or yawning. You can also try a method known as the Valsalva maneuver, which involves holding your nostrils closed and closing your mouth while you exhale with force. 

If your symptoms persist or if you’re experiencing pain, visit your physician to determine what’s causing the blockage and if treatment is needed.

To help reduce nasal congestion and clear the middle ear of drainage, your doctor may recommend one or more of the following treatments:

• Nasal saline spray
• Decongestants
• Antihistamines
• Corticosteroids

If your blockage is caused by an infection, your doctor may prescribe antibiotics. 

For severe ETD symptoms that won’t go away, surgical options are available. Tympanostomy tubes, also known as ear tubes, may be inserted to help with persistent drainage and blockage in the middle ear.

Balloon dilation of the eustachian tube can also help some patients. In this procedure, a balloon catheter is placed in the eustachian tube through the nose, filled with saline, emptied, and removed. 

For Patulous Eustachian Tube

Patients with patulous eustachian tube can manage symptoms in several ways.

Your physician may recommend that you put your head down between your knees when symptoms occur. Treatment may consist of nasal sprays or topical nasal administration of medications including diluted hydrochloric acid, chlorobutanol, and benzyl alcohol.

For patients with severe cases, surgery may also be an option.