Labyrinthitis - Causes of labyrinthitis

Labyrinthitis is caused by inflammation of part of the inner ear known as the labyrinth. This is caused by an infection.

How the labyrinth works

The fluid-filled channels of the labyrinth are known as the vestibular system. All the channels are connected and are at different angles.

When you move your head, the fluid inside the channels of the labyrinth also moves. This tells your brain how far, fast and in what direction your head is moving, which allows your body to balance properly.

The vestibular system works in a similar way to a stereo, with your right ear sending one signal to your brain and your left ear sending another signal. If one ear becomes infected, these signals become out of sync and the mismatch between the two signals can confuse your brain. This triggers many of the symptoms associated with labyrinthitis, such as dizziness and loss of balance.

The labyrinth also contains a small, spiral-shaped cavity called the cochlea. The cochlea sends sound waves to the language processing areas of the brain. Inflammation in and around your cochlea can disrupt this function, leading to hearing loss.

Viral labyrinthitis

Around half of all cases of viral labyrinthitis are thought to be caused when a viral infection of the chest, nose, mouth and airways – such as the common cold or flu – spreads to the inner ear.

Infections that affect the rest of the body, such as measlesmumps or glandular fever, are a less common cause of viral labyrinthitis.

Bacterial labyrinthitis

Labyrinthitis can sometimes be caused by a bacterial infection. This is rarer than a viral infection and is likely to be more serious.

Bacteria can enter the labyrinth if the thin layers of tissue that separate your middle ear from your inner ear are broken. This can happen if you have a middle ear infection or an infection of the brain lining (meningitis). Bacteria can also get into your inner ear if you have had a head injury.

© Crown Copyright 2009