Otitis

Middle ear

The middle ear is also known as the tympanic cavity and, as one may suppose, is situated between the external ear and the inner ear.

In fact, we could say that it is a chamber that is connected with the throat via the Eustachian tube, which acts like a valve regulating the pressure inside the middle ear and which connects up with the external auditory canal via the tympanic membrane or eardrum.

The eardrum is a very fine membrane that separates the external ear from the inner ear, and just behind it lie three tiny little bones known as the malleus, incus and stapes. This last one, the stapes, is the smallest bone in the whole body.

Altogether, the ear structures are very delicate and their functioning is very complicated, because the sound reaching the membrane (eardrum) has to be adapted and conducted through to the inner ear.

A large part of the work done by the middle ear consists in regulating the pressure. That's why the Eustachian tube is so important. This tube-like structure is usually closed, except when we yawn or swallow, when it opens. If you've ever been in an aeroplane or up a mountain you've probably felt your ears go "pop". That's nothing more than the Eustachian tube opening up to make sure the air pressure is the same on both sides of the eardrum, that is, inside and outside the ear.

If this pressure were not kept regulated ... our ears might burst!!