Expert: Harriet B Jacobster, Au.D. - 10/15/2008

Question
Dr Jacobster,
I just wanted to follow up with you and ask you some more questions. If you recall, I was injured in Baghdad by an explosion, that knocked me out for a few seconds and ended up damaging both more eardrums.(My ENT and I both agree I perforated both and they had begun to heal back). Worse, I have had a terrible time with pressurization (diagnosed as ETD) and had ear tubes inserted.

Since I last posted, my ETD has been off and on...ears still don't feel like they are equalizing like they should. I also keep accumulating scar tissue and wax on my eardrums that the ENT keeps having to scrape off. Worse, my tinnitus is getting worse and I feel my hearing is getting worse. (I also suffer from migraines, vision problems, and cognitive effects from the TBI but I'll leave that alone).

Here's what I wanted to ask you about. The military has tested my hearing twice and concluded my hearing is just fine. I'm told my hearing is at the 10-20 dB level(all frequencies) and I guess anything below 20 dB is normal. In my latest test...they had to warble the tone b/c the tinnitus got in the way...but I could hear the beeps. But I don't feel right. I hear people talking...but it sounds like they are mumbling so I have to ask them to repeat all the time.I've asked the military about this and I keep getting the answer that if I'm above 20 dB "everything is normal". This really concerns me....my wife has noticed it too. In noisy restraunts...I have a tough time picking out conversation from clutter. I'm very frustrated...the problem seems to be getting worse, not better.

I found my old medical records and I scored 0 dB at all freq except 6000hz on the rt where I was 10 dB in 1999. ( I had good hearing). Is there any reason my hearing would degrade like that....I just turned 32..so I was 23 in 1999.

Help.

Nate  

Answer
Hi Nate,
I am sorry to hear you are still having so many problems.  There are essentially two basic parts to "understanding" speech.  The ear, the peripheral organ, is the conveyor of sound to the brain, but it is truly the brain, the central organ, that decodes sounds and words.  So it is entirely possible to have normal peripheral hearing yet still not be able to understand.  This is known as an Auditory Processing Disorder (APD).  An APD will not show up on a basic auditory evaluation; there are special tests for it.  With a history of TBI, it is very possible that it is indeed your brain, and not your ears, that is causing your difficulties.  I am listing two websites for you to check on:  http://www.ncapd.org/php/  and  http://www.ncapd.org/links.htm  The second site deals a lot with children; do not be put off by this as most research deals with APD in children.  However, it is very prevalent in adults as well.
My advice is to speak to your audiologist and find out about being tested for APD.
Hope this helps.
Harriet B. Jacobster, AuD
Board Certified in Audiology