What is a Tympanogram?

A tympanogram, also referred to as a tympanometry, is a testing methodology to examine how the middle ear is functioning. To perform a tympanogram, a medical care provider, usually an ear doctor, places a probe inside the ear that alters the air pressure and causes the eardrum to vibrate. Results help to determine if the eardrum is punctured, if fluid in the ear exists, and if the middle ear system is working properly. The test can be done on patients of all ages.

Results are recorded on a graph produced by a machine called a tympanometer, which examines the capacity of the eardrum to reflect sound. A person's eardrum, also known as a tympanic membrane, is flexible. The greater the ability to reflect sound usually indicates higher mobility.

While the tympanogram is being performed, a person will often be asked to remain still and refrain from talking or swallowing. Any such movement can alter the pressure in the middle ear and could result in an inaccurate result. To perform the test, a person’s ear will need to be free of debris and requires an airtight seal between the probe’s tip and the ear. During the tympanogram, a patient will hear tones that may be loud and the probe can cause discomfort. The time required to perform the test usually is less than two minutes.

A tympanometer is a hand-held probe that is placed in the ear. The probe consists of tubes that include a loudspeaker, a microphone, and a pump. When the instrument is placed in the ear, an airtight seal is created against the wall of the inner ear. Through the loudspeaker, a tone is sent as the pressure is modified within the sealed canal. The microphone records the amount of sound that is echoed back during the test and the data is recorded on a graph.

The information from the tympanogram is based on data and does not require any responses from a patient. Insights into the ear that may be learned from the test include tympanic membrane movement and middle ear pressure. The outcomes of a tympanogram are then charted on a graph and labeled as either Type A, B, or C.

If a patient's result fall into Type A, the movement of the tympanic membrane is considered normal. A Type B reading often is a sign of minimal or no tympanic membrane flexibility, which often requires medical treatment. A Type C result can indicate a tympanic membrane with negative pressure. This tympanogram reading can be the result of retraction of the tympanic membrane or obstruction in the Eustachian tube.