The Eustachian tube is a bony-cartilagneous tube that connects the middle ear (the area behind your eardrum) to the back of the nose. The opening of this tube allows your middle ear pressure to equalise with that of the outside environment.
For example, when you are in areas of high altitude (e.g. in the plane or in an elevator going up a high floor) you may feel "blocked" in the ears because of the pressure difference between your middle ear and the outside environment. When you open the Eustachian tube (e.g. by swallowing, yawning or performing a Valsalva manoeuvre), you will hear a clicking sound and the "blocked" feeling disappear. The opening of the Eustachian tube in a high altitude environment allows air/pressure from the middle ear to escape to the back of your nose.
As the Eustachian tube opens into the back of your nose, problems with your nose and sinuses can affect the function of the Eustachian tube. In a cold/flu, the mucous or swelling of the lining of the nasal cavity may partially block the opening of the Eustachian tube. This results in inability of your middle ear pressure to equalise with that of the outside environment. Most of the time, this resolves with time after your cold/flu has settled.
You should visit an ENT Specialist to have an assessment if your symptom is persistent (e.g. a few weeks after your cold/flu). An ENT Specialist will take a full clinical history and conduct a thorough head and neck examination including examination of your ear and nose. It is quite likely that a nasoendoscopy (relatively painless scope through the nose under local anaesthesia) and a hearing test will be required. Eustachian tube disorder is a clinical diagnosis achieved by a combination of clinical history and physical examination. Sometimes one part of the hearing test to assess compliance of the eardrum (known as tympanometry) may yield a result that suggest a Eustachian tube dysfunction.
Treatment of Eustachian tube dysfunction includes treating the underlying nose conditions. Nasal steroid sprays, decongestants and Valsalva manoeuvres (blowing out against a pinched nose and closed mouth - to "pop" your ear) may be effective in relieving your symptoms. In severe cases, pressure equalisation tubes (placed through the ear drums) or ballooning of the Eustachian tube may be considered. These procedures are however not commonly required in most Eustachian tube Dysfunctions.
Hope this helps and all the best!
