Question for all cochlear implant recipients

Thanks for the link. I’d be surprised if Envoy Medical were using anything other than standard testing because they’d want an apples to apples comparison with other CI manufacturers.

It might be that this cohort of participants delayed implantation for a long time and have suffered from auditory deprivation more on average than those who chose a non-fully implantable solution. We need more details about the participants.

This is all we know: "Key inclusion criteria were as follows: ≥18 years of age, good health and absence of significant morbidity, English fluency, post-lingual deafness, pure-tone thresholds indicative of at least a bilateral severe-to-profound sensorineural hearing loss with limited benefit from amplifications (defined by an aided consonant-nucleus-consonant word score of ≤40% in the ear to be implanted and ≤60% in the contralateral ear), and normal middle ear function (as detailed by exam and tympanometry (type A, AS, or AD)).

Key exclusion criteria were as follows: more than 10 years of documented severe-to-profound hearing loss; an air-bone gap greater than 10 dB at two of 500, 1000, 2000 and/or 4000 Hz; prior surgery in the middle ear, inner ear, neck, or interclavicular fossa that is anticipated to prevent proper placement of the device; a cochlear anomaly that might prevent complete electrode insertion; and diagnosed auditory neuropathy or other retrocochlear cause of hearing loss."

Source: Initial Experiences with the Envoy Acclaim® Fully Implanted Cochlear Implant - PMC2

I had an aided audiogram for pure times about a month and a half after activation. It generally put everything in the 30-35db range. That’s the only test I had with the CI and have not had another since - it’s just been testing sentences and words on annual mappings.

Let me explain with a practical example. A traditional audiometry test is performed in a quiet booth, without hearing aids and wearing headphones. You are then asked to listen to various frequencies, typically from 125 Hz to 8000 Hz, and you are then asked to indicate when the sound of a single frequency is barely perceptible. Free-field audiometry, the topic I’m currently interested in, is performed with hearing aids in place and a speaker about a meter away. Here too, you are asked to indicate when individual frequencies are barely perceptible. This allows you to determine the actual gain of the hearing aids. Is this free-field test performed on cochlear implant recipients?

Interesting. Was this test done in streaming or in a free field, that is, listening to the sounds emitted by a speaker? Did the 30/35 dB apply to all frequencies from 125 to 8000 Hz?

@lello58 said:

Is this free-field test performed on cochlear implant recipients?

Yes, I had, at physical appointments in Jan 2024 and probably today in the noon. And also remotely during RemoteChecks, however without any return reports.

Functional gain here:

HA - that was my Audéo Paradise P90-RT, 9 months before I started DIY, with awful mid-, and high frequency fitting…

However, REM is better than functional gain for assessing amplification, because it has validated ISTS speech input instead of pure tones and can assess inputs in 50, 65 and 80 dB (and OSPL90).

@garenio said:

The test was done free-field in front of a speaker with the frequency range measured from 500 to 4000hz according to thr audiogram.

I don’t know, why 6 and 8 kHz aren’t tested, regarding that range can be crucial for clarity. Frequency response on CI are pretty up to ~8500 Hz.

Thanks for posting the graph. I also don’t understand why they didn’t also test the 6000 and 8000 frequencies, which are very important for understanding dialogue.
As a movie buff, the frequencies below 250 are also very important: do you know how low your CI goes?

@lello58 said:

As a movie buff, the frequencies below 250 are also very important: do you know how low your CI goes?

CI frequency range is about 70 to 8500 hertz.

What you’ve been told doesn’t seem right to me. Thanks to the frequency transposition, I can hear the high frequencies 6000 and 8000 quite well, and that helps me a lot..

The only times I had an aided soundfield testing was when I had my CI evaluation, and at the end of my 12 month assessment.

The rest of the time it’s just my AuD’s voice doing WRS and sentences. I can’t remember having a pure tone testing on my CI ear.

for me, free-field testing was completed during CI evaluation with hearing aids (PTA and words/sentences), as well as after implantation at my 1 month (PTA and words) and 3 months post-activation (PTA and words/sentences). for PTA, we only tested from 250hz - 6khz when implanted.

as i continue my appointments for this initial year, i believe i will be tested again at 6 months and at 12 months, again with free-field. it’s given us a great baseline to work off of. i’m also doing audio-verbal therapy, and we have been doing non-clinical tests to see how well i do, since the SLP isn’t sure what else we can improve upon during our sessions.

pictured is my progress so far after our testing.

@lello58 said:

What you’ve been told doesn’t seem right to me. Thanks to the frequency transposition, I can hear the high frequencies 6000 and 8000 quite well, and that helps me a lot..

Perhaps I wrote it inaccurately: it’s not that 6-8 kHz isn’t important for hearing (it’s important). The point is that TESTING these 6-8 kHz according to the current state of science does not bring any benefits, but only extends the time of the patient’s visit, limits something that is referred to as “appointments streamliness”.

This is like testing extended-range audiometry. Perhaps one day in the future it will be clinically beneficial to perform it in all patients, but current state of science does not confirm this so far.

Perhaps, with the advent of xMEMS receivers with frequency response up to 20 kHz, that measurement in all patients will make more clinical sense.