What can cause abnormal ABR?

[Nancy T]

Hi, and thanks for answering questions here!

Do you know what could possibly cause a "highly abnormal" ABR, once acoustic neuroma and MS have been ruled out?

What I'm really curious about is whether MIGRAINE can damage the nerve pathways and cause an abnormal ABR.

I am a migraineur though only mildly so; I don't get bad headaches.

My history includes long-term, low-level dizziness (I am 55, it started 30 or so years ago). In 1999 it got worse and I finally started seeing doctors about it; have had normal ENGs, various medications tried, even PLF exploration, but never got a diagnosis for my dizziness. I finally "diagnosed" myself with migraine-related dizziness.

In 1999 I had sneezed and lost the hearing in my left ear in frequencies above 750 Hz (severe to profound loss).

After a normal MRI, the otoneurologist ordered an ABR and the results (in my normal-hearing ear, and in my bad ear in the frequencies which could be tested) were "highly abnormal." Some of the values are more than twice the normal, even in my good ear.

But no one ever explained to me what could cause this. I assume there is some kind of damage to my 8th nerves on both sides (and the acoustic reflex decay was also highly abnormal on the left at 500 Hz, I think), but what could cause this?

Thanks for any ideas!

Nancy

[Nancy T]

Thank you VERY much for your reply. It is extremely interesting to hear that there may be a relation between migraines and abnormal ABR.

I do know about the common relation between migraines and vertigo/dizziness.  Since migraine is a CNS disorder, it does not seem surprising they could affect the auditory nerves/pathways as well.

In the past I did try searching for any info on a migraine-ABR connection and found nothing--but when I searched on some of the terms you used, up popped the 2008 study in India and a couple of other articles! I am VERY excited to find this information, as it gives me at least a plausible explanation for those abnormalities.

I do have some other strange symptoms, e.g. I once had some very strange BPPV as described in this thread:

http://www.medhelp.org/posts/Hearing-Loss/Strange-BPPV-episode/show/724078

and a long history of electric shocks in my face, so perhaps migraine has really done a number on my cranial nerves--even though my headaches are truly minimal and my dizziness is very mild compared to what some migraineurs suffer.

Your reply and finding confirmation of a link between abnormal ABR and migraine is somehow a huge relief to me. It was so frustrating to see doctors, get no answers, and eventually be made to feel that you can't ask questions anymore. Thanks again!! :)

Nancy

[Cindy Beyer, Au.D.]

This sounds like a complex case and I can understand why you still have questions.  It may not be possible to be specific in the diagnosis due to the some of the complexities of the auditory and neural pathways.  There are several articles on migraines and vertigo and also the effects on the audiovestibular system which I found through internet searches.   One article reports a high incidence of vertigo and tinnitus with migraines, and suggests that ABR evoked abnormalities may be an early indicator of impending auditory involvement in migraines.  So it seems that the answer to your question about migraines causing abnormal ABR is that yes, it appears possible.