Re: pressure/deafness

[David Mountain <dcm@xxxxxx>]

I don't understand your statement "it is possible to see a direct
link between action of the stapedius muscle on the stapes and
intracochlear pressure." A static displacement of the stapes would not be
expected to cause a change in intracochlear pressure because the
helicotrema and round window act as a pressure release system.


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David C. Mountain, Ph.D.
Professor of Biomedical Engineering
Boston University
44 Cummington St.
Boston, MA 02215

Email:   dcm@bu.edu
Website: http://earlab.bu.edu/dcm/
Phone:   (617) 353-4343
FAX:     (617) 353-6766
Office:  ERB 413

On Fri, 20 Jun 2003, Andrew Bell wrote:

> Susan Allen asked:
>
> >>> susan allen <susie@shoko.calarts.edu> 11:51:56 am Friday, 20 June 2003
> >>>
> >I'm not a specialist, but is it then possible that elevated blood
> >pressure could contribute to deafness?
>
>
> Indeed, blood pressure can affect hearing.
>
> Although the effect is not normally a major one, in people suffering
> Meniere's disease an increase in pressure can trigger a full-blown attack.
> They tend to suffer low-tone fluctuating deafness, and significantly, the
> pitch is perceived higher in the affected ear. Subjectively, most patients
> report a feeling of "fullness" or pressure in their ears.
>
> Menieres disease can sometimes be treated successfully by placing the
> patient in a pressure chamber. Moreover, of particular interest, a recent
> paper (Franz et al., Acta Otolaryngol. 123, 2003, 133-137) reports that
> cutting the tendons of the middle ear muscles relieved symptoms in all 20
> Menieres patients studied. In this context, it is possible to see a direct
> link between action of the stapedius muscle on the stapes and intracochlear
> pressure.
>
> Again suggesting a link between pressure and deafness, there are some
> interesting cases of "sudden idiopathic deafness", an uncommon condition
> which appears to be triggered by increases in blood pressure. Simmons (Arch.
> Otolaryng, 88, 1968, 67-74) reported cases where the precipitating factor
> was coughing, stooping to pick up a golf ball, getting out of bed,
> performing a Valsalva manoeuvre, and after diving. The patient suddenly lost
> 80 dB or so of hearing sensitivity, which sometimes persisted for weeks (and
> sometimes permanently). To assist recovery, Simmons recommends that such
> patients avoid "nose blowing, swimming, sudden postural changes,
> intercourse, and more than modest amounts of alcohol."
>
> Hallberg's report on sudden deafness (Laryngoscope 66, 1956, 1237-1267) is
> also of interest because in a surprisingly large number of cases the
> deafness came on suddenly in both ears and was attributed to "vascular
> accident".
>
> More recently, Preyer (1996) studied the relationship between sudden
> deafness and the weather (Laryngorhinootologie 75, 443-446) and found that
> patients with complete recovery were characterised by the smallest changes
> of atmospheric pressure and temperature.
>
> Andrew Bell.
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Andrew Bell
> Research School of Biological Sciences
> Institute of Advanced Studies
> Australian National University
> Canberra, ACT 0200, Australia
> andrew.bell@anu.edu.au
> phone +61 2 6125 9634
> fax +61 2 6125 3808
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>