Tympanometry provides a way, along with a physical exam, for doctors to diagnose and monitor problems in the middle ear. The middle ear is located behind the tympanic membrane (eardrum).
Tympanometry can help diagnose disorders that can lead to hearing loss, especially in children. The test measures the movement of your tympanic membrane in response to changes in pressure. The tympanic membrane is a thin tissue that separates the middle and outer ear segments. The results of a tympanometry are recorded on a graph called a tympanogram.
The test can tell your doctor if you have:
- fluid in your middle ear
- otitis media (middle ear infection)
- a perforation (tear) in the eardrum
- a problem with the Eustachian tube (the tube that links the upper part of the throat and nose with the middle ear)
Your child’s doctor may perform tympanometry every few weeks for several months to chronicle how much fluid they have in their middle ear over time.
Before the test, your doctor may look inside your ear canal with an otoscope, a special instrument for looking in the ears. This is to make sure there’s no earwax or a foreign object obstructing your eardrum.
Next, they’ll place a probe-type device in your ear canal. It may feel a little uncomfortable, and you’ll hear loud tones as the device begins to take measurements. This test changes the air pressure in your ear to make the eardrum move back and forth. Measurements of the movement of your eardrum are recorded in a tympanogram.
You won’t be able to move, speak, or swallow during the test. If you do, it may give an incorrect result. If your child is having tympanometry, you may need to show them beforehand how the test will be done using a doll. This can help them prepare for loud noises and practice being still.
The test takes about two minutes for both ears. People of all ages can have tympanometry, which usually takes place in a doctor’s office. There are no risks related to the tympanometry test.
Normal results mean:
- There’s no fluid in the middle ear.
- The eardrum looks smooth.
- There’s normal pressure in the middle ear.
- There’s normal movement of the eardrum and the conduction bones (the bones that aid in hearing).
Normal pressure inside the middle ear can vary between +50 to -150 decapascals (daPa). Decapascals are a measurement of air pressure.
Abnormal results may reveal:
- fluid in the middle ear
- perforation of the tympanic membrane
- scarring of the tympanic membrane (usually from frequent ear infections)
- middle ear pressure beyond the normal range
- tumors in the middle ear
- earwax blocking the eardrum
- lack of contact between the conduction bones of the middle ear
A tympanometry only really tests for problems with the middle ear. Other tests should also be performed to diagnose a condition. If your test results are abnormal, your doctor will send you for additional testing and a follow-up appointment with a specialist.