The Inner Ear
and Ménière's Disease
The hearing and balance canals of
your inner ear consist of hard bone that is lined with a soft
membrane. An important fluid called endolymph circulates in both the
cochlea (hearing canal) and the semicircular (balance) canals. In the
cochlea, movement of endolymph caused by sound waves transmits sound
signals to the brain. In the semicircular canals, movement of
endolymph sends messages to the brain about the position of your body
in physical space.
In Ménière's Disease, excess
endolymphatic fluid accumulates in the hearing and balance canals,
causing pressure to build and the canals to swell. The swollen canals
cannot function properly, which may cause the symptoms of Ménière's
Disease. When there is pressure in the hearing canal, the brain
receives confusing sound messages that cause roaring or ringing in the
ear (tinnitus), or the brain does not receive messages at all (hearing
loss). When fluid accumulates and pressure builds in the balance
canals, the brain receives "error messages" about the
movement and position of your body, creating the sensation of vertigo.
| The Normal
Inner Ear |
 |
| A |
The endolymphatic sac
Keeps inner ear fluid at a constant level. |
| B |
The balance canals
Collect balance information. |
| C |
The hearing canal
Collects sound information. |
| D |
The hearing and balance
nerve
Carries information to the brain from both parts of the
inner ear. |
| The Abnormal
Inner Ear |
 |
| A |
The endolymphatic sac
Backed-up fluid in the sac and inner ear leads to swelling
and pressure. |
| B |
The balance canals
Swelling in the balance canals distorts balance information. |
| C |
The hearing canal
Swelling distorts or blocks sound information. |
| D |
The hearing and balance
nerve
Distorted information travels from the inner ear to the
brain.
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