Need help understanding what's possible with a certain level of loss

Hearing Loss
1

Hi, I am new to this forum. I am the mother of a wonderful little boy who is now 2 1/2. He’s had such a complicated history. I won’t go into it all, just enough to say he was born very early (23 weeks exactly) and we adopted him. He failed two hearing screenings (right ear only) in the NICU and we were referred to an audiologist. In October 2009, at the adjusted age of 2 1/2 months, he was found to have moderate to moderately severe hearing loss…pretty much a flat loss in each ear, the left one a moderate loss of 50 to 55, the right one a little worse at 55 to 65. It was across all frequencies, nothing better than 50/55. They repeated the test a couple months later with very similar results. They made sure his eardrums were turning at the time of the tests and the ENT checked for fluid in between the two tests as well. The loss was deemed sensorineural. We got his hearing aids that December.

Fast-forward to last February. I noticed my son was hearing a little better than he should have been without his aids. He couldn’t hear my whispers with his back turned, in the bath tub, but he could hear my very soft voice, maybe 35 or 40 dB. In March I was shocked when he heard the train inside our closed up house for the first time. It’s a good mile away, so not super loud. By July he was noticing the soft chimes from the church behind our home. In August I decided to check his whispers again and he could hear me well, back turned, a good eight feet away, and even somewhat at 12 feet away. Of course, our audiologist didn’t believe my tale for a long time, which I understand…sensorineural hearing loss isn’t supposed to get better. We tried to do two different booth tests last winter with him but he wouldn’t cooperate. He just cried or wouldn’t acknowledge the intern outside who was saying the same thing over and over to get him to look…after a couple looks, he was done. But probably a lot of 1 1/2-year-olds would have been too. The audiologist got a range of 60 to 70 at the time, in his better ear, even, and I told her there was no way. We finally were able to schedule an ABR during his tonsillectomy last September and the results were pretty astounding…his left ear had improved to 30 to 40 dB across the board and the right one had improved to 35 to 45 dB. The audiologist doing the testing (not his regular one) couldn’t explain it, except to say that maybe he was so sick early on that things took a while to get going, but she assured me whatever improvement had come must have happened right after that last infant ABR, at 4 months corrected, and that it hadn’t gotten better since. But I knew differently because I lived the progression last year, when my son was a toddler. Although we were very happy with the ABR results confirming his improvement, it still didn’t seem to match what I was seeing at home.

Well, just this week I decided to test him once more without his aids. I had read about the whisper test the army used to use and decided that was somewhere to start. So I turned his high chair around and measured 15 feet with a tape measure and asked him a series of 7 questions, all whispered…things like “What does a cow say?” “What does a cat say?” “What does a chicken say?” etc. He was 7/7, no problems at all differentiating even cat and cow, whispered, at 15 ft. I was shocked because I knew that meant he could possibly have normal/minimal hearing, at least at the frequency I was whispering at. The phone rang right then; it was my mom and I told her the good news. As I hung up the phone in the other room, I was walking back and wondering in my head if I had whispered softly enough, so I whispered one of the questions again, so I could hear it: “What does a sheep say?”…and lo and behold he answered me! This was way back of where I had been before. So excitedly I began asking him some things from back there, including, “Do you want to go out and play?” All whispered, and he said, “Outside pay” as he signed both. I couldn’t believe it. He got the majority, though not all, of the things I asked at that distance. Then I measured it to compare–it was 24 feet! From my own research and calculations, I found that a typical whisper is 30 dB at 3 feet, and that when you double the distance you lose 6 dB, but even more is lost if it’s high frequency. I assume whispers would count as high, but even if they didn’t, that would mean he heard and undestood quite a bit at just 12 dB. Is that even possible if his range is truly only 30 to 45? And actually 40 to 45 at the 4000, where I am going to guess whispers may be? I would totally think not, but when I called his audiologist to relay everything, she said that sometimes her children with mild losses can hear her, she’s noticed, in her little testing room, sans aids. But I am assuming she means in a talking voice, not a whisper. And I know it couldn’t be from 24 or even 15 feet, as those are cubby hole rooms! It was like she downplayed everything again (it’s been that way kind of all along).

Am I putting too much hope into this, or do my findings have merit? Can most people with mild to moderate loss (and nothing normal or slight at all in their range) hear whispered voices, with backs turned, so far away? She asked if there was background noise and I said no, but I don’t think I could undestand a whisper at that distance with background noise. She basically seemed to imply that what I witnessed, in quiet, could be possible for someone with a mostly mild level of loss. But isn’t the decibel level at each frequency supposed to be the softest sound you can hear well? Could a person who’s softest registered decibel is a single 30 at the 2000 in the left ear understand 100 percent of whispers at 15 feet and 75 percent at 24 feet with back turned? I would think it’s impossible, but I guess I am looking for confirmation on that from people who know a lot more about hearing loss and testing than I do. I need to get all the info I can before we head in for a booth test on Friday, because I am not sure what will happen even if we get good results. I am just hoping he cooperates this time, and since he’s older now, maybe he will. They will do a game version this time with him, so he may think it’s more fun. I just need some advice and encouragement, I guess. I realize that everything that’s happened so far with my son goes against everything his audiologist was taught about sensorineural hearing loss, the amount of improvement he’s shown. And here I am claiming even further improvement. I can understand how it would be hard to come to terms with, but at the same time, I want what’s best for my son. He’s going to be entering preschool this August and the last thing I want is for him to go in there with his aids blaring. He has started really fighting us on putting them in and it’s even brought tears. I asked him if they just hurt to go in or are they loud, and he said loud. His speech therapist has noticed no difference in sessions with or without his aids now either. Basically, she thinks it is just a minimal loss now too and she had the ABR level pegged right last year, so she’s good at estimating losses, it seems. And there are other things…he wakes up from his nap on the second floor anytime my husband and I talk in normal voices on the first floor, so we have to remember to talk in hushed voices only while he’s sleeping. I even wake him up occasionally when I clear my throat downstairs!

I am really nervous that he won’t perform and I will have a real dilemma on my hands about what to do with the aids. Luckily we have 6 months to get a good test in before preschool starts though. Thanks for reading and sorry it’s so long! Any advice or improvement on my math or my understanding of the different levels of hearing loss and what’s possible and what’s not at a certain level, anything at all I may be missing or need to know before our booth test, is appreciated. Also, does a booth test where the patient is found to be cooperative trump an ABR? I have heard that it should, because of the “brain factor” that is involved with hearing, but I am still unsure myself of what we’ll find.

2

No advice for you, but as the mother of a son who has worn hearing aids since 18 months I’m thrilled for you! The hearing tests are difficult at that age. Are the people doing the tests experienced with toddlers? I recall stuffed animals that lit up and moved (like a monkey playing cymbals) as a reward for when he looked at the speaker making the tones.

The first time my son was diagnosed, by the end of a long sound booth test he was falling asleep so they were able to put the probes in his ear that they use to test newborn hearing with. That would not have worked with him awake but it confirmed what they found in the sound booth with his responses. Later the ABR confirmed both.
Good luck.

3

The problem with ABR’s is as close as they can get to accurate, they are still not as precise as a hearing test where your patient can sit and raise their hand when they hear the softest sound possible.

So, I’d guess that it’s possiblethat your sons’ hearing could be slightly better than the ABR indicated and that the hearing aids are too loud which is why he’s resisting wearing them. It’s also possible that he has become very good at discerning your voice among others and that’s why he did so well on the whisper test. Also, there’s no way to know exactly how loud you were whispering or what kind of effects the acoustics of the room had on the level of the sound that was reaching him (reflective surfaces could have amplified your voice perhaps). I’m not trying to quash your hopes that his hearing is better than suspected. Every child that doesn’t have hearing loss is a happy day for me! But, I would put a little more weight in the idea that he has experienced some improvement in his hearing possibly from continued development but also because he may be starting to be a better participant during testing. All that automated testing tells you is what the system is capable of, not what the brain actually does with the sounds it receives.

My suggestion would be to see if the audiologist can/will turn the hearing aids down a little to the point where they are comfortable for him to wear but still go on the assumption that he has a mild hearing loss. Kids resist wearing hearing aids even when they have profound losses often so you can’t use that as a guide to the level of his hearing. Even mild losses have significant impacts on speech and educational development so it’s important to keep him aided even if his hearing loss is mild.

4

In my case, ABR test showed result at 80 db but my loss is around 90 db. Do ABR tests differ from standard hearing test ? I was put to sleep for ABR.

5

Yes, an ABR technically does not test your hearing which is the ability of the brain to interpret the sound it’s receiving from the ear. The ABR tests the nerve-fibers’ ability to fire in a synchronous way or it tests the ability of the ear to transmit the sound. By decreasing the intensity of the stimulus sound we see less and less synchronous firing and eventually we reach a point where we don’t see the response we are looking for. That level approximates where the cochlea ceases to transmit a loud enough sound for the nerve fibers to fire synchronously and is an estimate of the threshold for whatever stimulus is used. In children if you are trying to fit a hearing aid you should be using tone bursts which are more frequency-specific instead of a click which is a sound that is only testing higher frequencies and isn’t specific to certain high frequencies.

The test tells us nothing about what the brain is doing with the sound. It also is not as precise as a person sitting in your room raising their hand. It’s been a long time since I’ve done an ABR but I believe the level the response disappears at on an ABR can be as much as 10-15dB off…but again, that’s remembering stuff from a long time ago. I do know that it’s not the same as a behavioral threshold (raising your hand) though.

6

Thank you all for your replies. Maureen–that test sounds like of like the one they used with Andrew last year, at 1 1/2, when he didn’t want to cooperate. I am wondering if it might be better for him to have that test this time, too rather than the more complicated game test. Our speech therapist wanted to know how many pictures were on a page for him to have to scan through, as she feels too many may distract him. He loves to look for details in things, and the pictures will interest him, but maybe too much, she fears. Thanks for your kind words.

DocAudio–thanks for explaining some of the science behind it all. I didn’t even think of the acoustics that could be contributing to the scene. I was on a hard tile floor and he was in a high chair on a vinyl floor, and there was a doorway in between us. I guess when I said it was quiet, that may have been misleading because it wasn’t totally quiet like a library. There was a ceiling fan on with a slight hum, near him, and there’s minor traffic outside, but not much. The walls were just normal, drywall. I agree about the whisper loudness factor…that’s one thing that makes the test less reliable. I will say it wasn’t a faint whisper, but I tried to be average with it. Today I didn’t want to formally test (not to overdo things), but as he was eating I went as far as I could to one side, in line with his better ear (the 30 to 40 one) and later measured it and I was 8 feet away, so a closer distance. However, the set-up was different, with one ear turned toward me, and the furnace was running at the time, near him, so there was more noise than last time. I made sure this time to whisper faintly, I am guessing more of a 15 to 20 dB whisper vs. 30, but that’s just a guess. He heard me great. I did the same thing on the other side of him, then, with his 35 to 45 dB ear, but was 10 feet away. He understood me, but I could tell his reaction time was a little longer.

What you said about the ABR is what we learned too…that it leaves out the all-important brain factor, which is why they do like to get a booth test in. Our one speech therapist thinks even if he has to have just a soundfield test, if he refuses to leave the headphones on, that it will tell us more than we know now. She said we won’t get a true picture of what he can hear until he is old enough to raise his hand to respond, like at 4 or 5. I do think he’s doing more with it than what the equipment said, via the ABR. We were told a little better or worse was possible. Your 10 to 15 better is, in my head, probably where we may find his hearing truly lies.

What you said about him tuning into my voice is a possibility too. We don’t whisper all the time, but still, he’s going to be tuned in to speech more than other sounds, probably, so it wouldn’t surprise me if his speech recognition score is better than the pure tone one. I guess we’ll see. But that’s only if we do something better than last January’s test, where the intern kept saying the same thing over and over: Oh, oh, look, look, Andrew. He didn’t look too often after that initial one, but I would have tuned it out too. They have to mix things up if we do that kind of test again. I was thinking that’s where the picture one might be better, but I guess we have to see how complicated that one will be. The good news is he willingly wore some headphones here today, to listen to music, so it’s a start.

We were told that one ABR could only be at most 10 decibels better than a past one, at any spot, and that that was pushing it. So we know Andrew’s hearing progression is unusual, to have done what it did. Here are his ABR results for December 2009 (which was within 5 dB of his October 2009 one) and then for September 2011:

Dec. 2009

500 1000 2000 4000

R 55 60 60 65

L 55 50 50 55

Sept. 2011

500 1000 2000 4000

R 40 35 40 45

L 40 35 30 40

As you can see, it was quite a gain, as high as 25 dB in the right ear at the 1000. And again, no fluid was present at the time of testing…just basically the impossible happened, we were told. So nothing seems out of the realm of possibility to me now. I do think, though, that we could get these exact ABR results if he were tested with it tomorrow. This is probably a brain thing I am seeing, the hidden factor we don’t have a reading on yet for him. Plus or minus 10 (or more)…I could easily see these scores getting better by 10, even 15 dB. But then what? Do we go by the booth test results as what he’s hearing? I don’t want to get my hopes up, but if he did have a left ear that was all 15 to 25s, would that mean that ear may not need an aid anymore, because his brain was compensating for what was wrong with his hearing equipment? Would the sound booth test be the one we would look at above all else? I would think so, but I just don’t know. Our audiologist hesitated to turn down the aids after the September test, but I insisted. Like I said, I know this isn’t something she’s run into before. I could only find one other case on the net, these past months, and it was a 24-weeker who had improved by 30 decibels. I think it is definitely tied to prematurity…like the ear isn’t 100 percent set at birth and the body chose to put things on hold and concentrate on other things, like breathing. But then slowly over time the hearing has improved. I don’t know if that makes sense or not, especially that it improved even 2 years later, but that is how it’s appeared to me.

Thanks for all the tips. I will ask about turning the aids down even if he doesn’t cooperate for the test. I am hoping that won’t be a problem, though.

7

I’m not a pediatric audiologist which really is a field kinda all unto itself. But, yes, any kind of behavioral information usually trumps any physiological measurements. The only issue with soundfield testing is that when you have no headphones you can’t say which ear is the one doing the hearing. BUT, if your son was tested and he responded in the 10-15dB range then you would know that at least the hearing in the better ear is within normal limits. I’d say that if his hearing was documented to be less than about 20dB at some point then he wouldn’t need a hearing aid in that ear. I don’t want you to get your hopes up just in case it doesn’t turn out that his hearing is as good as you are hoping/suspecting. Also, if his hearing IS improving there’s nothing to say that whatever caused the improved fluctuation won’t take the fluctuation in the opposite direction at some point down the road. Don’t want to be Debbie-downer but I also want to keep all possibilities open.

I’m thrilled for his apparent improvement. Hopefully it will continue or ‘stick’.

8

Thanks for your advice. It’s good to hear an audiologist’s angle on it. I would be very surprised if we got a cooperative test in and he didn’t have some hits as low as 15 dB, at least, from what I am seeing.

They don’t call his loss fluctuating, although I know it’s gone up a lot. It’s definitely been a steady progression over a long, long time, from what I can see. Some of it’s obviously physical, and I guess my delayed finshing up of the equipment/23-weeker theory is in regards to that part of it. Beyond that, I think he’s had some tremendous growth in the brain department (including cognitively, where he gained 25 points in one year), which I think could be from a whole bunch of things, including all the DHA he’s had in his toddler years, first from toddler formula and now from a supplement. But above and beyond that, there is training to detail, listening for sound, speech therapy, and his very young age…so many things I think that might have helped him to have experienced greater neural growth than may be typical here. We’ve even been protecting him from germs since we brought him home–so 2 1/2 years. His doctor wants us to keep him away from other kids and be careful with him until he’s 3 due to his lung issues in the NICU. His immune system has only had to fight off two very minor colds in all that time. I read recently where they think it’s a combination of the immune system and stem cells that have helped (or will help) some children gain back hearing, in these stem cell trials. We don’t have the stem cell part, but could a strong immune system that’s free from weekly or monthly typical toddler infections have had a chance to work on one longterm problem? Just a theory, but that too might explain some of the ABR gains if it’s possible.

They call his loss a medicine related one, and they said that kind doesn’t get worse, so I was never concerned about it progressing, although you bring up an interesting point. I don’t feel this is all a fluke. I do think it’s something that will stick, and hopefully continue to get better. But I know we can’t be sure. However, I do have some fear of more hearing loss for him in the future, but for a very different reason. We adopted Andrew, but it’s a family adoption. My husband is biologically his great uncle. And my husband and his sister and brother (who is Andrew’s biological grandfather) all have a cookie bite loss, which is obviously genetic, that manifested itself in their teens/twenties and is progressive in nature. Interestingly, their parents do not have hearing loss, though one grandfather did. My husband’s cookie point is in the moderate range now, at the 2000. He isn’t aided yet (though he needs to be and has done some of the leg work for hearing aids), and he reads lips. At the 500 his hearing is good–5 dB in one ear. It’s not bad at the 1000 either. At the 4000 it’s sloping downward now to reach the mild range, probably work-related loss, etc. The second generation of kids in the family are all in their twenties now, and so far there are no reports of hearing loss among them, that we know about. But I do worry that could be in Andrew’s future too.

But it’s the comparison between my husband’s and Andrew’s hearing that showed me way back that my son could out hear my husband, except for the low noises. Even on the higher end, where they are now supposed to be the same, it isn’t even close. When I was whisper testing Andrew before, several times, my husband would be 3 , 4, 5 feet from me and not even have realized I said anything, while Andrew, a good 12 feet away, not only heard me but was answering my questions. There’s no way those two have equal hearing at the 4000, if that’s where a whisper is. Yet on paper right now, they are both mild there, with Andrew’s numbers somewhat worse. I got real faint with him today, barely 15-20 dB, I would say, and had background noise thrown in and he didn’t disappoint. Something’s definitely up with his ears, but we just have to hope for a good, valid booth test. I’ll keep you posted on how it goes. Still not sure of which one we’ll end up picking either…they both have their good and bad points. If it doesn’t work, at least we have 6 months until he begins preschool. I definitely want a good test in by then!

9

Yes with the family loss with an onset later in life then that is definitely something to watch for.

Have you ever thought about having a genetic work-up? If the family members with the hearing loss are identified with a specific genetic marker then if you son has the same one it would give you some idea of what to potentially expect. It’s a thought…

10

We had the genetic testing for Connexin 26 done through the ENT, but I believe that’s all they tested for. It came back negative, which doesn’t surprise me, since I don’t think the type of loss usually caused by Connexin is a cookie bite. Could someone do genetic testing on my husband to find out exactly what faulty gene he has and then look for that in our son? They saved some of the blood to use in future experiments, but I doubt we hear anything.

11

My knowledge about genetic testing beyond the Connexin gene is essentially zero. If you wanted a more thorough workup you’d probably have to contact a geneticist, perhaps the pediatric audiologist you work with knows of one?

12

Thanks, I will ask her to see what she thinks. It would be nice to know so you can plan ahead.

Tomorrow’s the big day and the little guy’s pretty stopped up. I am hoping it won’t be a factor, but if he does more poorly than we think, we will take him back in in the coming months. His one SLP was here yesterday and stood near him during our little experiements to see what the whispers sounded like. She said it sounded faint, like she was straining to hear (and she’s very young). She doesn’t think his hearing is much worse than her own, which gave me more hope. We’ll see how it goes. BTW, she did think the acoustics in the kitchen supported the sound waves more easily, so we moved out to the foyer to try some. It was neat to get another person’s opinion on it all, and she has experience with the whisper test and knows it is unreliable simply because you don’t know how loud you’re doing it.