131 - Clinical Evaluation and Management of the Eustachian Tube

Abstract

The eustachian tube is a conduit that connects the nasopharynx to the middle ear cavity and contains a functional valve. It acts as a dynamic, long ostium to the middle ear and mastoid, which are analogous to an accessory sinus. Its primary functions include: (1) ventilating and equalizing pressure in the middle ear space, (2) draining secretions from the middle ear cavity by gravity and mucociliary clearance, and (3) protecting the middle ear from reflux of nasopharyngeal material, pathogens, and sounds. Patients can develop difficulty in adequately opening the eustachian tube, resulting in obstructive eustachian tube dysfunction and problems with ventilating the middle ear and clearing secretions. Alternatively, they can develop difficulty closing the valve resulting in patulous eustachian tube dysfunction and problems with protecting the middle ear from sounds transmitted from the nasopharynx. These disorders occur on a spectrum of severity ranging from complete occlusion to consistently open, and some patients may transition between patulous and obstructive eustachian tube dysfunction. Although a thorough history and physical exam can help properly diagnose patients, nasopharyngoscopy has improved our ability to diagnose pathology of the eustachian tube more rigorously. For obstructive eustachian tube dysfunction, tympanostomy tubes can relieve symptoms by bypassing the eustachian tube entirely, whereas new techniques such as balloon dilation of the eustachian tube aim to address the source of pathology directly. For patulous eustachian tube dysfunction, a variety of medical and surgical management options are available. This chapter will discuss the diagnosis and management of eustachian tube pathology and novel treatments.