Tympanometry is a test used to detect disorders of the middle ear.

Before the test, your health care provider will look inside your ear canal to make sure there is a clear path to your eardrum.

Next, a device is placed into your ear. This device changes the air pressure in your ear and makes the eardrum move back and forth. A machine records the results on graphs called tympanograms.

You should not move, speak, or swallow during the test. Such movements can change the pressure in the middle ear and give incorrect test results.

The sounds heard during the test may be loud and potentially startling. You will need to try very hard to avoid being anxious and becoming startled during the test.

If your child is to have this test done it may be helpful to show how the test is done using a doll. The more familiar your child is with what will happen and why, the less anxiety he or she will feel.

There may be some discomfort while the probe is in the ear, but no harm will result. You will hear a loud tone as the measurements are taken.

This test measures your ear's responses to the sound and different pressures.

The pressure inside the middle ear can vary by 100 daPa (a very small amount). The eardrum should look smooth.

Tympanometry may reveal any of the following:

• A tumor in the middle ear
• Fluid in the middle ear
• Impacted ear wax
• Lack of contact between the conduction bones of the middle ear
• Perforated ear drum
• Scarring of the tympanic membrane

There are no risks.

Noble J. Textbook of Primary Care Medicine. 3rd ed. St. Louis, Mo: Mosby; 2001:1733-1735.

Cummings CW, Flint PW, Haughey BH, et al. Otolaryngology: Head & Neck Surgery. 4th ed. St Louis, Mo; Mosby; 2005:3514.