 The Eustachian tube links the middle ear to the back of the nose and is designed to open to allow the pressure in the air-filled middle ear to be equal to external atmospheric pressure. In some people this system fails to work properly leading to abnormal pressure in the middle ear, and complications such as middle ear fluid glue ear or damage to the ear drum. The abnormal function of the Eustachian tube is called Eustachian tube dysfunction. An affected person may feel pressure, pain or other symptoms in their ear, and their hearing can be temporarily or permanently reduced. 