耳管
The Eustachian tube plays the primary role in the pathophysiology of disorders of the middle ear. Access to the proximal part (ear side) of the eustachian tube is limited since most of the existing surgical access is posteriorly through the mastoid cavity. The endoscope allows the surgeon to reach the protympanum or the bony Eustachian tube and possibly carry out interventions to maintain an open eustachian tube by inserting a dilatation balloon catheter into that area.