Eustachian Tube Dysfunction
The eustachian tube connects the space behind the eardrum to back of the throat. It’s purpose is to prevent the build up of air pressure behind the ear. The tube is typically close, but is designed to open with yawning and swallowing. Eustachian tube dysfunction is a condition where that tube either doesn’t open properly or doesn’t close properly. It can be caused by a muscle problem or excessive mucous.
Diagnosis: Dysfunction of the eustachian tube is usually symptomatically diagnosed by a physician and can be confirmed by an audiologist using an immittance bridge.
Treatment: Eustachian tube dysfunction is usually treated by medication designed to decreased the amount of mucous in the tube. Severe cases can also be treated with pressure-equalizing tubes or severing the muscle keeping the eustachian tube open.
Otitis media is an infection of fluid in the middle ear space. If the eustachian tube remains closed (see above), significant negative pressure can build up behind the eardrum. That pressure can cause seepage from the surround tissue that may eventually fill the space behind the eardrum. The fluid prevents proper transmission of sound and can become infected if not drained.
Diagnosis: Otoscopy and tympanometry can be used to diagnose otitis media. A tympanogram tests the eardrums flexibility. If fluid is behind the eardrum, flexibility is significantly decreased.
Treatment: Otits media is often treated with antibiotics, which will treat the infection and alleviate the pain. However, antibiotics do not always permit proper drainage of the trapped fluid. In severe cases, an ENT surgeon will drain the fluid by placing a small incision in the eardrum.
Otosclerosis is a condition in which the movement of the middle ear bones is impeded. The footplate of the stapes (or stirrup) can become fixated, which prevents the proper transmission of sound. Otosclerosis often occurs gradually and is linked to family history.
Diagnosis: Otosclerosis can be diagnosed using tympanometry and the audiogram. Due to the fixation of the stapes, it affects air and bone conduction thresholds differently, which is manifested by a particular shape on the audiogram.
Treatment: Otosclerosis often warrants replacement of the stapes through surgery. In some cases surgery may be contraindicated, in which case, hearing aids can be very affective.