‘Explanation’ of CI Evaluation

As a follow-up to his disappointing Cochlear Implant evaluation last Friday, Brandt sent an e-mail to Marie, his audiologist at Dr. Awesome’s clinic.  She is the audiologist who fitted his hearing aids and who we go to every time there’s a problem with the aids, iCom, or FM system.  Marie did not think that Brandt was a CI candidate, and has recommended since we met her last summer that he wait until his hearing loss has declined further before getting the evaluation.  Even though she didn’t agree with Dr. Awesome’s decision to send Brandt for the evaluation, she was still hopeful for our sakes that we would have a more positive outcome than we did, and wanted a full report afterwards.

Since we were upset and confused from the results, Marie contacted Tiffany, the audiologist who conducted the evaluation at the separate CI clinic.  Her e-mail back to Brandt attempted to explain why he was deemed to not be a Cochlear Implant candidate:

“The reason [Tiffany] stated to me that they did the HINT [Hearing in Noise Test] in quiet only is because you did so well.  The FDA requirement to qualify for cochlear implant is that the ear to be implanted must score lower than 50% and the non-implanted ear must score lower than 60% on sentence testing. In your case, the test was done initially bilaterally (both ears).  If your scores had been lower, then [they] would have then done the exam in the individual ears to determine candidacy.  However, since you scored so well, you are not a candidate based on FDA requirements.  They could have done other testing, but you would not have been a candidate based on these scores and therefore they felt it unnecessary.”

So if I understand this correctly, Tiffany did not perform the actual test that is used to determine candidacy, but assumed that based on his high binaural score, that he would do too well when his individual ears were tested.  I can understand that this is probably the case, but I still want to know what his individual scores are and think he should have the further testing done.

Brandt asked Marie why there would be such a discrepancy between his very low Speech Discrimination score (24%) and his very high HINT in Quiet score (90%).  She explained:

1. “The testing we did here was done at a level much higher than threshold to overcome part of the hearing loss.
2. The testing we did was UNAIDED—NO Hearing Aids.
3. The testing we did was WORDS in quiet.
4. The testing done [by Tiffany] was actually a completely different kind of test…
5. The testing done [by Tiffany] was done at conversational level AIDED—WITH Hearing Aids.
6. The testing done [by Tiffany] was done BILATERALLY—Both ears at the same time.
7. The testing done [by Tiffany] was a sentence test—not single words.”

Which means:

“Based on these differences, I would fully expect that you would do better on the sentence testing because there is more context to be gained from a sentence than from single words.  In that situation, even if you misunderstood part of the words, the context of the sentence let you fill in part of the blanks.  In a single word condition, the word could be any word out of thousands.  The single word test was done UNAIDED which means we were presenting at an extremely loud level which helps to overcome some of the hearing loss.  The loud presentation level gives us a chance to see how your system functions when things are presented at a loud level (basically, how do you do with more volume).  However, sometimes the loudness actually distorts some parts of speech, so it is not a perfect test (name one that is :-) ).  Also the testing we did was in individual ears and did not give the binaural boost that the brain actually applies when you are hearing with two ears.  Basically, that means that your processing system actually gives a natural boost when you are hearing information from both sides.  Because of these circumstances (sentences vs. single word, both ears vs. single ear, loudness presentation levels, etc.) comparing the score on the HINT to the score on the single word test is like comparing apples to oranges.”

Also remember from the CI evaluation that Tiffany ran a computer test on Brandt’s hearing aids and determined that they “are not programmed correctly,” and offered to “fix them.”  Marie’s response to this was: 

“As far as the hearing aid programming is concerned, yours are fit appropriately for your specific hearing loss and environmental needs.  Unfortunately, the testing done [by Tiffany] was simulated real ear measurements and not done on your ear.  They used normative values for a 2 cc coupler ear canal volume whereas we used your actual ear canal volume to determine appropriate fit (in other words, not everyone’s ears are the same and we took in to consideration your actual size and shape of your ear canal to program the hearing aids, not a simulated, generic coupler).   Also, they are looking only at loudness for “vowel sounds” being low frequency and were not taking into consideration how your system functions in your specific listening environments with background noise present.  I fully stand behind the way your hearing aids are programmed and I would not suggest changes based on their input.  I actually am very impressed by your sentence scores and feel it verifies that your hearing aids are fit appropriately and that you are functioning at the best possible level for your abilities.”

Brandt’s upcoming semester—both teaching and trying to finish his doctorate—is going to be extremely busy, so we don’t know when exactly he’ll be able to go back for further testing.  Another audiologist at the CI Clinic, Bobbie, has already looked at Brandt’s chart and agreed to meet with him for more testing.

Stay tuned…