Timpanomeetria

Timpanomeetria, also called tympanometry, is a diagnostic test used to assess middle-ear function by measuring the movement of the tympanic membrane in response to controlled changes in air pressure within the external auditory canal. The test yields a tympanogram, a graphical plot of middle-ear compliance across ear-canal pressure, helping to infer middle-ear pressure, membrane mobility, and ear-canal volume.

In practice, a probe containing a loudspeaker and microphone is placed in the ear canal. The device delivers a pressure sweep from positive to negative values and records how the tympanic membrane moves. Key parameters include peak compliance, ear-canal volume, and the pressure at which the peak occurs. Tympanograms are commonly classified into types: A (normal), As (stiff), Ad (hypermobile), B (flat), and C (negative pressure).

Clinical uses include evaluation of pediatric otitis media with effusion, suspected Eustachian tube dysfunction, and monitoring middle-ear status after infections or surgery. It is often performed with audiometry to guide treatment decisions and to assess suitability for procedures such as tympanostomy tubes or tympanoplasty.

Limitations and interpretation: results depend on an adequate seal and a clear ear canal; cerumen, canal anatomy, or very small ears can yield unreliable data. Tympanometry does not identify the exact cause of middle-ear disease and should be interpreted in the context of clinical history and other tests.

Timpanometry is widely used in otology and audiology for noninvasive assessment of middle-ear function and is a routine component of hearing evaluations and pediatric screenings.