The cause of
Ménière's disease is unknown, but it may be related to
a fluid imbalance in the inner ear. This fluid (endolymph) is
contained in a part of the inner ear called the endolymphatic sac.
In endolymphatic sac decompression, a small amount of bone is removed
from inside the ear. This provides more room for the endolymphatic sac when it
swells with too much fluid. By providing more room for the sac to swell,
pressure inside the inner ear is avoided and vertigo does not develop.
This is considered a relatively low-risk procedure. It usually does
not cause hearing loss.