What is measured at peak compliance on a tympanogram?

The measurement taken at peak compliance on a tympanogram is static admittance. Static admittance reflects the maximum compliance of the middle ear system at a specific pressure, which is indicated by the peak on the tympanogram.

When conducting tympanometry, the tympanogram plots how the compliance of the tympanic membrane varies with changes in air pressure in the ear canal. At peak compliance, the pressure in the ear canal is equal to the pressure in the middle ear, allowing for optimal movement of the tympanic membrane. This results in the maximum admittance of sound energy, which is what static admittance quantifies.

Understanding static admittance is crucial for interpreting tympanometric results, as deviations from normal ranges can indicate various middle ear pathologies, such as fluid in the middle ear, eustachian tube dysfunction, or issues with the ossicular chain.