Subject: SOAEs and tinnitus From: Brian Gygi <bgygi@xxxxxxxx> Date: Wed, 7 Oct 2009 17:11:40 +0000 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>----=_vm_0011_W352665323_32197_1254935500 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable The problem is that there are also people (e.g., myself) who have tinnitu= s but exhibit no SOAEs. Further, SOAE's don't really "sound" like tinnitu= s - there are several different "sounds" of tinnitus, suchas ringing, "cr= ickets" and very rarely a low frequency hum. I have crickets myself. This= is the problem, as perviously stated, with grouping all disorders that k= ind of behave like tinnitus under one heading, when they might have sever= al different etiologies. Brian -----Original Message----- From: Andrew Bell [mailto:andrew.bell@xxxxxxxx Sent: Wednesday, October 7, 2009 12:43 AM To: AUDITORY@xxxxxxxx Subject: Re: Technique can pinpoint tinnitus Matt and list:Thanks for pointer to Ceranic et al (1998), a paper which g= ives clearevidence that spontaneous otoacoustic emissions (SOAEs) and tin= nitus areclosely related. If SOAEs sound like tinnitus and behave like ti= nnitus,isn't it likely that they are (in some respect) tinnitus?If we are= aiming to pinpoint tinnitus, then SOAEs offer the most directtool, and C= eranic et al. support this idea. Their Table 5 shows thatpatients with he= ad injury and tinnitus displayed 4.4 SOAEs per ear, comparedto 1.7 with n= ormals and 0.25 with those having head injury without tinnitus.So did the= head injury damage the cochlea and generate a tinnitus sensation(via aff= erent pathways), or did the injury damage the brain, which respondedby se= nding a signal to the cochlea (via efferent pathways)? As you say, thatqu= estion is still very much open, but it would definitely repay someattenti= on.Andrew.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~Andrew BellResearch Schoo= l of Biology (RSB)The Australian National UniversityCanberra, ACT 0200, A= ustraliaT: +61 2 6125 5145F: +61 2 6125 3808andrew.bell@xxxxxxxx~~~~~~~= ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~> > Further, tinnitus can also be induced = by head injury [6]. In > this case, it is possible that the inner ear is = damaged and > this causes a peripheral type of tinnitus, which again is a= > cochlear amplifier dysfunction. Until we can successfully > trace this= cause and develop methods such as cellular > regeneration possibly using= stem cells - we can tinker and > experiment using all sorts of procedure= s to quash the > problem, but they will never be as sophisticated as actu= ally > repairing the biology.> > > > [6] @xxxxxxxx{ceranic:1998,> author =3D= {Ceranic, B.J. and Prasher, D.K. and Raglan, E. > and Luxon, L.M.},> tit= le =3D {{Tinnitus after head injury: evidence from > otoacoustic emission= s}},> journal =3D {Journal of Neurology, Neurosurgery \& Psychiatry},> ye= ar =3D {1998},> volume =3D {65},> pages =3D {523--529},> number =3D {4},>= publisher =3D {BMJ}> }> ----=_vm_0011_W352665323_32197_1254935500 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable <html><div> <br>The problem is that there are also people (e.g., myself) = who have tinnitus but exhibit no SOAEs. Further, SOAE's don't reall= y "sound" like tinnitus - there are several different "sounds" of tinnitu= s, suchas ringing, "crickets" and very rarely a low frequency hum. = I have crickets myself. This is the problem, as perviously stated, = with grouping all disorders that kind of behave like tinnitus under one h= eading, when they might have several different etiologies.<br><br>Brian <= br><br></div> <blockquote style=3D"border-left: 2px solid rgb(0, 0, 255); padding-left:= 5px; margin-left: 5px; margin-right: 0px;"><font face=3D"Tahoma" size=3D= "2">-----Original Message-----<br><b>From:</b> Andrew Bell [mailto:andrew= .bell@xxxxxxxx<br><b>Sent:</b> Wednesday, October 7, 2009 12:43 AM<br>= <b>To:</b> AUDITORY@xxxxxxxx<br><b>Subject:</b> Re: Technique can = pinpoint tinnitus<br><br></font>Matt and list: Thanks for pointer to Ceranic et al (1998), a paper which gives clear evidence that spontaneous otoacoustic emissions (SOAEs) and tinnitus are closely related. If SOAEs sound like tinnitus and behave like tinnitus, isn't it likely that they are (in some respect) tinnitus? If we are aiming to pinpoint tinnitus, then SOAEs offer the most direct tool, and Ceranic et al. support this idea. Their Table 5 shows that patients with head injury and tinnitus displayed 4.4 SOAEs per ear, compa= red to 1.7 with normals and 0.25 with those having head injury without tinnit= us. So did the head injury damage the cochlea and generate a tinnitus sensati= on (via afferent pathways), or did the injury damage the brain, which respon= ded by sending a signal to the cochlea (via efferent pathways)? As you say, t= hat question is still very much open, but it would definitely repay some attention. Andrew. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Andrew Bell Research School of Biology (RSB) The Australian National University Canberra, ACT 0200, Australia T: +61 2 6125 5145 F: +61 2 6125 3808 andrew.bell@xxxxxxxx ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Further, tinnitus can also be induced by head injury [6]. In > this case, it is possible that the inner ear is damaged and > this causes a peripheral type of tinnitus, which again is a > cochlear amplifier dysfunction. Until we can successfully > trace this cause and develop methods such as cellular > regeneration possibly using stem cells - we can tinker and > experiment using all sorts of procedures to quash the > problem, but they will never be as sophisticated as actually > repairing the biology. > > > > [6] @xxxxxxxx{ceranic:1998, > author =3D {Ceranic, B.J. and Prasher, D.K. and Raglan, E. > and Luxon, L.M.}, > title =3D {{Tinnitus after head injury: evidence from > otoacoustic emissions}}, > journal =3D {Journal of Neurology, Neurosurgery \& Psychiatry}= , > year =3D {1998}, > volume =3D {65}, > pages =3D {523--529}, > number =3D {4}, > publisher =3D {BMJ} > } > </blockquote></html> ----=_vm_0011_W352665323_32197_1254935500--