Middle ear myoclonus is a condition whereby
the muscles within the middle ear spasms or twitches creating a brief click sound. These irregular clicking noises like a geiger
counter are similar to the more common “eye twitching" or "facial twitching". BUT, instead
of being able to "see" the twitching, one hears the twitching instead since the muscles
are located within the ear. These irregular clicking noises should NOT be confused with
tinnitus which can be either a continuous tone or regular pulsations. Normally, sound travels through the ear canal
which then vibrates the eardrum. The eardrum in turn vibrates the malleus, then the incus,
followed by the stapes. The stapes then stimulates the cochlea which is the hearing organ resulting
in sound perception. Within the middle ear, there are two muscles
known as the tensor tympani and stapedius muscle. When either of these muscles spasm, it causes
a brief sound.
Why? The tensor tympani is a muscle located
in a bony canal above the eustachian tube and connects to the malleus bone. Its main
role is to dampen loud sounds, such as those produced from chewing, shouting, or thunder. So if the tensor tympani twitches, it pulls
on the malleus thereby resulting in movement of the middle ear bones and a sound perception. The stapedius muscle is the smallest skeletal
muscle in the human body. At just over one millimeter in length, its purpose is to
stabilize the smallest bone in the body, the stapes. But if this muscle twitches, it pulls on the
stapes bone also resulting in movement of the middle ear bones and a sound perception. Given muscles spasms always occur without
any rhythm, that’s why middle ear myoclonus produces an irregular clicking sound.
Unfortunately, there is no "test" to diagnose
this problem with absolute certainty. One can try to observe twitching of the eardrum.
However, the best way to diagnose is based purely on history and excluding palatal myoclonus
as a diagnosis. Anecdotally, this condition may be treated
with TriMagnesium supplements, muscle relaxants, and/or anticonvulsants. Definitive treatment
is to surgically cut the muscle..