understanding the anatomy and function of the the External, Middle and Inner Ear relative to OAEs
Posted by: Jude Liptak (ip24-254-202-245.hr.hr.c (IP Logged)
Date: May 10, 2005 10:27AM

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Re: Welcome
Posted by: Jude Liptak (ip24-254-202-245.hr.hr.cox.net)
Date: May 10, 2005 02:39AM

Hi Thierry,

I am an AuD student and have a question in one of my classes on OAEs and would like some help to get the perfect answer yawning smiley)
What do you think is the importance level of understanding the anatomy and function of the the External, Middle and Inner Ear in relation to the performance of the OAE Test and subsequent interpretation of the Test Results. Is it possible to perform testing and understand test results if in fact you do not fully understand the various anatomical sites the tests are evaluating besides the pass/fail screening? Please respond.

Thanks,
Jude

Re: understanding the anatomy and function of the the External, Middle and Inner Ear relative to OAEs
Posted by: Thierry MORLET (ip24-252-94-57.no.no. (IP Logged)
Date: May 10, 2005 10:28AM

Welcome
Posted by: Thierry MORLET (ip24-252-94-57.no.no.cox.net)
Date: May 10, 2005 05:05AM

As a diagnostician, I think it's of the utmost importance to understand the anatomy and physiology of all parts of the ear in both performing and interpreting OAEs. Of course, just about anyone can be trained to do a screening test which will render a pass or refer, but to interpret for example borderline results, absent OAEs in a child with tubes, or present OAEs in someone with a corner audiogram, one must know and understand the physiology of the ear and the mechanism of OAEs and how they are recorded. Also, in performing the test, it is crucial to be able to recognize the difference between possible stimulus artifact and a true response. I know that it is a current practice to consider that the outer and middle ears are functioning well when OAEs are present. What would you do when you have borderline OAEs (3 DPs present out of 6 for example)? If you don’t know the status of the outer and middle ears, you CAN NOT conclude anything about the supposed loss of outer hair cells in the cochlea. Your management will probably be wrong, right? Now, you have a patient with present OAEs and severe hearing loss according to a pure tone audiogram. What will you do? Some people would prescribe hearing aids…if you know the physiology of the inner ear, you would know that the amplifier in the inner ear is working absolutely fine; which means hearing aids is not the solution. To summarize, understanding WHY you are getting a Pass/Refer with the OAE test is crucial. Also, keep in mind that the OAE test tests only ONE part of the auditory system and that you need other tests to fully describe what’s going on. The best protocol to use is to test every patient starting with Tymps, Reflexes and OAEs, ABRs if necessary, followed by pure tones.
Let me know if I fully answered your question.