Eustachian tube patency refers to how much the eustachian tube is open. The eustachian tube runs between the middle ear and the throat. It controls the pressure behind the eardrum and middle ear space. This helps keep the middle ear free of fluid.
The eustachian tube is normally open, or patent. However, some conditions can increase pressure in the ear such as:
- Ear infections
- Upper respiratory infections
- Altitude changes
These can cause the eustachian tube to become blocked.
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