Eustachian tube patency
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:
These can cause the eustachian tube to become blocked.
Kerschner JE, Preciado D. Otitis media. In: Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 658.
O'Reilly RC, Levi J. Anatomy and physiology of the eustachian tube. In: Flint PW, Francis HW, Haughey BH, et al, eds. Cummings Otolaryngology: Head and Neck Surgery. 7th ed. Philadelphia, PA: Elsevier; 2021:chap 130.