Pediatric Tympanometry can also determine the function of the Eustachian tube. The Eustachian tube runs from the throat up to the middle ear. The Eustachian tube equals out the pressure in your middle ear with the atmospheric pressure. For example, on an airplane trip, when cabin pressure changes you may notice a “popping” sound or sensation. This is the sound of your Eustachian tube opening to equalize the pressure in your middle ear. Some individuals experience Eustachian tube dysfunction which can create positive or negative pressure in the middle ear which can lead to ear pain or discomfort.