Tympanometry

Tympanometry is a test that checks how well your middle ear is working. It measures how your eardrum moves when it reacts to a sound wave (vibration) and changes in the air pressure in your ears. An issue with your middle ear can affect how well you hear.

Your ear has three main parts: the outer ear, the middle ear and the inner ear. Sound travels into your outer ear as sound waves (vibrations). These vibrations make your eardrum move. When your eardrum moves, it sends the vibrations through your middle ear and into your inner ear. There, the vibrations change into electrical signals that your brain understands as sound, or noise.

Why would I need this test?

Tympanometry is often part of a complete hearing test. It gives your audiologist important information about whether your eardrum in your middle ear moves so sound can travel from your outer ear to your inner ear. This test is quick, safe and doesn’t hurt, making it a useful tool for both adults and children.

Your audiologist may use tympanometry to help identify conductive hearing loss, which happens when sound can’t move easily through your outer or middle ear. Issues like fluid in your ear, ear infections, a blocked ear canal, or eardrum conditions may cause this type of hearing loss.

The test can also help detect mixed hearing loss, which is a combination of conductive hearing loss and inner ear (sensorineural) hearing loss.

Your child may have this test to check for fluid in their ears. Fluid in their ears may not cause pain, but it can make sounds seem muffled. This may affect their speech and learning.

Tympanometry uses a device called a tympanometer to do the test and record the results. In the test, your audiologist places a small probe earbud into your ear. The earbud has three tiny openings (ports). Each port does different things:

• Sound port: This port sends a tone into your ear so the tympanometer can measure how your eardrum moves.
• Air pressure port: This port changes the air pressure in your ear. This shows how your eardrum reacts to different pressures.
• Measuring port: This port records how your eardrum and middle ear move. It sends that information to the tympanometer, which analyzes the results.

How do I get ready for this test?

You don’t need to do anything before the test. The situation may be different if your young child needs one. You can help your child feel comfortable about their upcoming test if you:

• Tell them that you’ll hold them on your lap during the test.
• Explain that they’ll have to sit still and not talk during the test.
• Practice touching your child’s ears at home so they get used to the feeling that the earbud in their ear will cause.

What happens during tympanometry?

You or your child will sit upright in a chair. You need to stay still and quiet because movement or noise can interfere with the test. Next:

• Your audiologist will gently place the earbud into your ear canal. It creates a seal to measure eardrum movement.
• The tympanometer changes the air pressure in your ear canal. This checks how your eardrum moves in response to different pressures.
• The earbud plays a tone. The test checks how your eardrum reacts to sound waves the tone creates.
• The tympanometer records your eardrum’s movement and the pressure of the middle ear. This helps identify issues like fluid, a ruptured eardrum or issues with your eustachian tubes.
• Your audiologist removes the earbud.

The test usually takes only a few minutes per ear.

What are the risks or side effects of this test?

Tympanometry is generally very safe and noninvasive. It doesn’t harm your hearing. Some people may feel slight pressure or fullness in their ear when the earbud changes air pressure. That feeling goes away when your audiologist removes the earbud.

What type of results will I get and what will they mean?

Your audiologist will show you a graph (tympanogram), which will show your test results. There are three types of tympanograms:

• Type A: The tympanogram will show a line that looks like it’s curving up and over a mountaintop. In this case, it will show if your middle ear works as it should.
• Type B: You may see a flat line. This result can happen if you have fluid behind your eardrum. Your audiologist or ENT may explain other possible causes.
• Type C: The line on the tympanogram looks like a smaller version of the curved line going up and over a mountaintop. The highest point doesn’t reach as high as the type A tympanogram. Issues like a sinus infection, cold or ear infection may cause this result.

What does an abnormal test result mean?

Your audiologist may say you have an abnormal test result if you have a type B or type C tympanogram. An abnormal result may mean you have:

• Fluid buildup or something blocking your middle ear
• A scarred eardrum from an infection or fluid
• Blocked or clogged eustachian tubes, which open and close to control air pressure in your ears
• Earwax blocking your middle ear
• Issues with bones (ossicles) in your middle ear
• A hole in your eardrum

Your audiologist may recommend that you see an otolaryngologist (ENT) if test results show issues with your eardrum. ENTs specialize in diagnosing and treating issues that affect your ears, nose or throat. In this case, an ENT may check for conditions that affect your middle ear, like fluid buildup, wax buildup blocking your ear or eustachian tube dysfunction.

You may have more hearing tests if you have abnormal test results and hearing issues. Your audiologist will explain the next steps, including specific tests to check your hearing.

What’s the difference between audiometry and tympanometry?

Audiometry (hearing test) checks how well you hear sounds. This includes how well you can distinguish various types of sound and how well you can hear quiet or loud sounds. Tympanometry tests how well your middle ear works by measuring eardrum movement. Both tests can help an audiologist diagnose issues related to hearing loss.