The pharyngeal end of eustachean tube is normally closed. It usually opens temporarily during swallowing and yawning during which time middle ear drainage and pressure equalisation takes place. Abnormalities involving this opening mechanism may lead to middle ear pathologies like otitis media with effusion.
Patulous eustachean tube is a difficult entity to treat. The phenomenon of autophony which is caused by this condition is a difficult entity to treat.
Patients have been driven to sucide because of this problem.