Your darn ears feel plugged after a viral illness such as a
bad cold or a grueling air flight (or both) where you’d swear the pilot was
having a jolly good time doing a few stunts while landing the plane, as the
copilot with the sick sense of humor intentionally messed with the cabin
pressure controls because he was bored out of his mind.
You clear or “pop” your ears by blowing your nose vigorously
or by doing a Toynbee Maneuver, where you exhale forcefully from
your nose against tightly-closed nostrils squeezed with your fingers. You feel a “pop” and the ear fullness and
hearing improves. You do this repeatedly
for the next few days to clear your ears.
When this occurred to you in times past, the ear problem
eventually resolved and you returned to your happy state of being. Yet after one particular flight or after a
bout with a really nasty virus, you find you’re still popping your ears. You do this over and over again…ad
infinitum…but disappointedly it doesn’t “stick”—your hearing doesn’t remain
permanently improved. So what goes?
The problem could be the eustachian tubes. As the prior post explains (The
Eustachian Tube Part 1: Ear Popping and Eustachian Tube Dysfunction)
air is forced into your middle ear (ME) from your eustachian
tube (ET) to equalize ME pressure.
Things that affect the eustachian tube, causing it to collapse and close
such as swelling of the tube from a cold or the pressure difference from a
change in altitude while travelling, will cause negative ME pressure. Blowing air into the ET and into the ME helps
to restore pressure back to normal and thus improve hearing and resolution of
the ear plugging or fullness.
After a while (and it can take months…yes, months!)
the ET recovers and the ME pressure remains constantly the same as atmospheric
pressure--the normal pressure of the environment outside the ear. However, some folks continue to “pop” their
ears with the Toynbee maneuver, despite the return of the ET and ME to its
normal state of being. They still feel
the need to clear the ears, noting a brief improvement in hearing.
These folks create a temporary condition of positive
middle ear pressure, or pressure that is greater that the outside
atmospheric pressure. This is a relative
term and this condition and, like negative ME pressure, is not
normal. Both problems cause
symptoms. Both can cause alterations in
the shape and sound conducting qualities of the ear drum or tympanic
membrane (abbreviated TM).
Another problem that leaves one with a sense of ear pressure
or ear fullness arises from the cochlea. After a viral illness or a session of loud
noise exposure such as a rock concert or the deafening roar of a crazy Chinese
New Year’s celebration where scores of people light whole packs of fire
crackers all at once, one often comes away with plugged ears and muffled
hearing, and perhaps a bit of ear-ringing to boot. Popping the ears is a natural thing to do,
but the effect is not related to restoring normal ME pressure, but temporarily
changing the TM shape and thus the hearing dynamics which can improve hearing
briefly. The ME pressure was never
changed during the noise exposure. On the
contrary, there is a loss of hearing due to injury to the inner ear--the
snail-shaped organ called the cochlea--caused by loud noise or a
viral infection of the ear. In this
case, it is the cochlear hearing loss itself that causes the plugged, full or muffled
sensation (we call this phenomenon aural fullness). As the cochlea recovers (hopefully), hearing
improves along with the sensation of fullness.
However, in some cases the hearing does not return to normal and that
sense of aural fullness persists.
Popping the ears in this case temporarily increases the pressure in the
ME where it is abnormally greater than atmospheric pressure. This causes the TM to bulge out and likely
changes its vibratory character and temporarily improves hearing. However, since the ET is functioning
normally, the ME pressure quickly equalizes and returns to normal and that
sensation of improved hearing goes away.
The problem is a state of positive pressure cannot be
maintained forever, nor should it. The
process of the ear returning back to its normal state may take a long while,
such that the improvements are not noticeable, due to the rather long
recovery. And once the ME and ET do
return back to their baseline, or if cochlear hearing recovers, there could be
a habitual problem of repeated ear-popping long after the necessity for this
has passed. Only now, the person feels
improvement above his/her baseline hearing.
In other words, the Toynbee maneuver causes a noticeable but hearing
improvement that is temporarily better than that person’s “normal” (or
baseline) state of hearing. As such,
he/she repeatedly pops the ears to “clear” them.
This phenomenon of aural fullness can also occur with more
gradual permanent cochlear hearing loss, where the ear fullness is felt
chronically without an antecedent cold or travel through altitudes. The hearing loss itself is the cause of aural
fullness and not the ME or ET.
If the ENT exam and tympanograms (device that measures
middle ear pressure) is normal, I try to convince these patients to avoid
popping their ears, since the need to do so has passed. If instead they are popping their ears by
manipulating their jaw (i.e., popping their TMJ, I strongly instruct them to
avoid doing this, since they aren’t opening their ETs but creating another
problem (see the post Ear
Popping and Crackling Noises),
Patients often feel in these situations that if the pressure
could just release from the ear by popping a whole in the TM or placement of a
ventilation tube, all will be well. On
the contrary, a tube would simple equalize ME pressure; air crossing to and
from the tube will naturally keep the ME pressure normal at all times. And when the patient does a Toynbee maneuver
and blows air up into his nose, there will be little to no effect on the TM
since the air forced into the ET and into the ME will simply exit from the
tube. They’re literally blowing it out
of their ear and will notice no change in hearing.
On the flip side, there are no means to keep the ME pressure
greater than normal; this defeats the purpose of the ET. You don’t want to have continuous positive
pressure, since this will cause the TM to bulge and potentially pop a hole into
it, and resulting in no benefit. I’ve
had some people ask about plugging the ET, but this creates negative ME
pressure, leading to other things such as above, leading to more hearing loss
and ear pain.
So, in summary:
A Toynbee maneuver increases middle ear pressure and is
helpful while having an actual eustachian tube problem (which causes negative
middle ear pressure) where pressure is returned to normal atmospheric
pressure. However, this can become a
habitual process once the middle ear and eustachian tube return to normal
function, and patients continue doing the maneuver unnecessarily. Positive pressure is created instead (which
is not natural) and will temporarily improve hearing due to alteration of TM
and thus changing the hearing dynamics
briefly. When the ET does recover, this
is no longer necessary and one should avoid doing this maneuver unless flying
or travelling through altitudes.
©Randall S. Fong, M.D.
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