Compliance in tympanometry is how well the eardrum and middle ear moves in response to air pressure changes.
Normal compliance indicates healthy middle ear function. Reduced compliance can suggest problems such as fluid buildup, eardrum stiffness, or other issues. High compliance, on the other hand, may indicate a perforation in the eardrum or other abnormalities.
As a result, tympanometry is an important factor in assessing middle ear health, function and possible hearing loss. It is also a good tool to indicate the status/health of the ear when performing diagnostic audiology.
What is the compliance of the tympanic membrane?
Typically, we measure tympanic membrane compliance by air volume change. This is often expressed in milliliters (ml) or cubic centimeters (cc or cm3).
The compliance of the tympanic membrane varies depending on factors such as its size, thickness, and tension. Generally, a healthy tympanic membrane will exhibit normal compliance within a certain range when subjected to tympanometry testing. This is shown by the height of the “peak”.
Typically, tympanograms are classified in the following manner:
| Type A tympanograms |
Type C tympanograms |
Type B tympanograms |
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These represent normal middle ear pressure with a peak between +50 daPa to -200 daPa.
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These indicate abnormally low middle ear pressure with a peak that is less than -200daPa.
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No pressure peak.
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Normal compliance values for the tympanic membrane typically fall within the range of 0.3 to 1.6 ml or cc. However, this can vary depending on the individual and the specific equipment used for testing.
Compliance values can indicate issues with the middle ear. These issues may include stiffness or holes in the eardrum, as well as fluid in the middle ear. Higher or lower compliance values and volumes (ECV) can be a sign of these problems.
What is the normal range for tympanometry compliance?
The normal range for tympanometry compliance can vary slightly depending on the specific equipment used and individual factors. Normal compliance values (according to BSA UK) are usually between 0.3 and 1.6 ml or cc.
Other factors can also influence compliance values. This includes age, ear canal volume, and the presence of any middle ear abnormalities. Therefore, it's essential to interpret the results of tympanometry in conjunction with other clinical findings and patient history.
Industry-leading tympanometers
We have a wide range of handheld and desktop tympanometers for fast and accurate middle ear measurements, catering for all age groups, including neonates.
Test progress and result information is displayed during and after the automatic test on large LCD displays, allowing for easy results interpretation. All methods can easily process this information to support the efficient delivery of patient care.
Our tympanometers also offer single-click integration to many third-party Electronic Medical Record (EMR) systems. Such as Noah, Auditbase, and OtoAccess® for seamless results and data transfer.
For more information on our range of screening and diagnostic tympanometers, please visit our tympanometers webpage. Or contact our customer support team on +44 (0)1865 880 846 or email.
References
British Society of Audiology, Recommended Procedure: Tympanometry and Acoustic Reflex Thresholds (Feb 2024). Accessed at: https://www.thebsa.org.uk/wp-content/uploads/2013/10/OD104-35-BSA-Recommended-Procedure-Tympanometry-and-ART.pdf