To better understand cholesteatoma, it helps to understand the anatomy of the ear.
Sound travels through the air as waves. Sound waves are collected and focused into the ear canal by the external ear. Sound waves strike the surface of the eardrum causing it to vibrate. The vibrations are then transmitted through a system of tiny bones (ossicles) in the middle ear.
Sound vibrations eventually end up in the inner ear, where they are converted into electrical impulses and sent to the brain. This occurs in a structure known as the cochlea. The cochlea is lined by tiny hairs, which, when stimulated by sound waves, send electrical impulses to the brain.
- Pinna: the cartilage and skin of the external ear
- Ear canal: passageway that leads to the eardrum
- Tympanic membrane: the eardrum
- Ossicles: three tiny bones that vibrate when sound waves strike the eardrum
- Inner ear, or labyrinth: includes the cochlea and semi-circular canals
- Cochlea: contains fluid and hair cells
- Semi-circular canals: contains fluid and hair cells
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