Eustachian Tube Function - Patulous Eustachian Tube (Extended License) - Interacoustics AA222 Instructions For Use Manual

AA222 Instructions for Use – US Page 37
3.6.10 Eustachian tube function – patulous eustachian tube (extended license)
Basically, the Patulous Eustachian Tube test is an impedance baseline test. It monitors changes in
impedance over time without applying pressure changes or acoustic stimuli. When a patulous Eustachian
tube is present you would typically expect to recognize the breathing of the patient in the tympanometry
curve. If the Eustachian tube is closed and the tympanic membrane is intact you expect to measure small
tympanometry changes which can be caused by acoustical disturbances from around the patient, accidental
displacements of the probe, or by spontaneous movements of the eardrum. Further it allows measuring
movements due to the heart beat in for example a glomus tumor. Or the test can be used to measure
reflexes where the stimulus is presented through an external device like a cochlear implant.
The default display of the Eustachian tube function test for the patulous Eustachian tube shows the graph for
the selected ear. Below is an example of a measurement in which the breathing rhythm of the patient can be
recognized due to the presence of a patulous Eustachian tube.