The Eustachian tube is a narrow tube-like passageway that connects the thimble-sized space behind the eardrum (the middle ear) to the space behind the nose. Its purpose is to provide a way for air to move in or out of the middle ear so that the air pressure in the ear is always equal to the air pressure around us, even with changes in external air pressure. When the Eustachian tube is working perfectly, it is closed and opens only very briefly when we swallow or yawn. There is a pulley-like muscle above the roof of our mouth that pulls it open when we swallow or yawn. Some people can actually hear a “crackling” sound every time this happens. Others hear it only sometimes, while some never hear it. Almost everyone becomes aware of this air movement when their ears finally “pop” during altitude changes such as during airplane flights or while ascending or descending a mountain or high elevator shaft. During these altitude changes, before the Eustachian tube opens to equalize the pressur ...

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