Swallowing induces contractions of the tiny muscles in the middle ear, which results in movements of the eardrum and middle ear bones. Middle ear pressure changes may also occur as the Eustachian tube is opened, permitting pressure in the middle ear to equilibrate with pressure in the pharynx. In our experiments, we have found that movements of the ossicles produce movements of the fluids of the inner ear. In a recent paper (Salt & DeMott 1999 J. Acoust Soc Amer 106, 847-856) we showed that movements of the stapes towards the cochlea, which cause pressure increase and small movements of the round window towards the middle ear, in turn induced a small movement of endolymph directed towards the apex of the cochlea. The movement was sustained for the duration of the middle ear muscle contraction (about 0.4 sec) after which endolymph returned to its original position. In view of this observation that middle ear muscle contractions can influence the cochlear fluids, we were interested how such movements affected patients with Meniere's disease.
Question asked : Normally, when the body is exposed to a pressure change, we feel the need to swallow to "clear" our ears.
How does Meniere’s disease affect your urge to swallow in these situations?
Possible Answers:
I swallow more often than I would without Meniere’s
I swallow less often than I would without Meniere’s
Meniere’s doesn’t affect the amount I swallow
A majority of respondents indicated that they swallowed more often, compared with extremely few who indicated they swallowed less often.
Question posed : Have any of the following ever made your symptoms better or worse?
1) Swallowing
2) Yawning
Possible answers to each :
(No) ( Yes - it made things better) ( Yes - it made things worse) (Don't know)
In marked contrast to the CSF pressure change activities on the previous page, it is apparent that middle ear movements are found to be beneficial in more patients than those in which symptoms are made worse. In the graph above, note that there is far more green than red, which contrasts with the summary of CSF induced pressure changes. Thus the transient fluid movements, or other effect of middle ear movements may influence fluid homeostasis in the ear
This question was answered by the 42 patients who reported that swallowing affected their symptoms
In this group, 40% found that chewing helped relieve their symptoms, while less than 10% reported adverse effects. Even in this sub-set of the entire group, approximately half of the respondents found chewing had no effect on their symptoms.
A Word of Caution : In the asymptomatic phase of Meniere's, fluid movements in the ear associated with chewing / swallowing are probably beneficial and are part of normal physiology. However, during the active phase of a vertigo attack it is possible that fluid movements could be very bad for the ear if there is damage to the boundary between endolymph and perilymph. Although we have no real evidence that chewing is harmful at this time, excessive chewing during acute attacks would not be recommend.
In the patients who did find that their symptoms were changed by chewing, the symptom most affected was that of fullness.
Question posed : Do you ever perform the Valsalva maneuver (holding your nose while blowing and simultaneously
swallowing) to help clear your ears?
Possible Answers:
1) Yes, I sometimes do this and I think it helps
2) Yes, I tried this and now avoid it because it made things worse
3) No, I have never tried this.
4) Yes, I tried this and it has no effect on my symptoms
Of the 74 respondents who answered this question, the numbers reporting good or bad effects were both fairly low (less than 20% each). Due to the large pressures that can be induced by this procedure, and the large movements of the middle ear ossicles, caution should be exercised if you ever use it.