The middle ear

middle-ear

When sound waves hit the eardrum, they cause it to vibrate, sending the sound on to the delicate machinery of the middle ear. Here, the body’s three tiniest bones mechanically advance and organize the sound to further amplify it and facilitate its passage into the inner ear.

The middle ear is an air-filled chamber that lies behind the eardrum. Pressure in the middle ear changes to match air pressure outside of the eardrum. When inside and outside pressures are balanced, the eardrum is flexible and normal hearing is more likely. Problems occur when air pressure in the middle ear drops. This is usually due to a block in the Eustachian tube, the narrow channel connecting the ear with the back of the throat.

As the link between the middle ear and the throat, the Eustachian tube has two roles. It helps drain normal, cleansing moisture from the middle ear. It also controls air pressure inside the middle ear chamber. When you swallow, the Eustachian tube opens. This balances the air pressure in the middle ear with the pressure outside the eardrum.

What are middle ear infections?

Middle ear infections occur behind the eardrum. These infections are usually due to bacteria or viruses, which are often related to a recent cold or allergy problem.

In many cases, both ears are affected. Middle ear infections are most common in young children, whose ear anatomy is not yet fully developed.

Children under age 5, bottle-fed infants, and children in day-care run the greatest risk of infection. Although much less common, middle ear infections can also occur in older children and adults. I'll cover this in more depth now as I know many of you are concerned about your children and grandchildren in this area.

Infections of the middle ear are particularly common in children aged 6 to 24 months. They are what the doctors call otitis media and are characterised by fluid build-up in the middle ear, behind the eardrum.

The middle ear normally produces fluid in small amounts. In healthy individuals, this reaches the nose through the Eustachian tubes and is easily eliminated. However, in individuals with a viral or bacterial respiratory infection, the process is impaired, leading to drain blockage and fluid build-up. From the throat, viruses and bacteria reach the middle ear, where they multiply causing its swelling, as well as that of the area around the Eustachian tube.

otitis-media

Rarely an emergency

Ear infections are very rarely an emergency. However, you need to see a doctor, if your child:

does not improve after a few days;
gets worse; and/or
has blood and/or pus in their ears.

Ruptured eardrum: is it bad?

Pus or blood discharge may suggest a ruptured eardrum. Although this requires medical attention, you can safely see your doctor within 24 to 48 hours.

Remember, a ruptured eardrum often means less pain, because the fluid that built up in the middle ear no longer presses against the eardrum. Also, the latter usually heals on its own. So, if your doctor says your child has a ruptured eardrum, keep in mind that, in most cases, this is not as alarming as it may sound.