Announcer: Welcome to Episode 23 of empowEAR Audiology with Dr. Carrie Spangler.
[00:00:16] Carrie: Welcome to the empowEAR Audiology Podcast, which is part of the 3C Digital Media Network. My name is Dr. Carrie Spangler, and I am your host. I am a passionate audiologist with a lifelong journey of living with hearing challenges in this vibrant hearing world. This podcast is for professionals, parents, individuals, with hearing challenges and those who want to be inspired.
[00:00:45] Thank you for listening, and I hope you will subscribe and invite others to listen and leave me a positive review. I also wanted to invite all of you to visit and engage in the conversation on the empowEAR Audiology Facebook group. Transcripts for each episode can be found at www. 3, the number three, C digital media network .com under the empowEAR Audiology podcast tab.
[00:01:18] Now let's get started with today's episode. Hi everyone. Welcome to the empowEAR Audiology Podcast. I am really excited for this conversation today. And I'm gonna welcome our guest today, Dr. Rene Gifford. She is a professor in the department of hearing and speech sciences with a joint appointment in the department of otolaryngology.
[00:01:42] She is currently the director of the cochlear implant program at the Vanderbilt Bill Wilkenson center and the division of audiology, as well as the director of the cochlear implant research laboratory. Her current research interests include combined electric and acoustic stimulation with cochlear implants, speech and auditory perception for adults and children with hearing loss and spatial hearing abilities of individuals combining hearing aids and cochlear implants.
[00:02:13] Dr. Gifford's research has been NIH funded for nearly 20 years. She has published over 125 peer reviewed articles, multiple book chapters, and she authored a book now in its second edition and tied on cochlear implant, patient assessment, evaluation of candidacy, performance, and outcome. She was the 2015 recipient of the Louis DeCarlo award, but recent clinical achievements based on her work with hearing preservation.
[00:02:45] Implant recipient. And finally, Dr. Gifford received the 2017 Vanderbilt chancellor's award for research, which recognizes excellence on the part of faculty for published research, scholarship, or creative expression. And she is the 2021 with that being the Jerger, Research career award. [00:03:07] From the American academy of audiology. So Dr. Gifford welcome today to the podcast. I'm so excited to have you.
[00:03:15] Rene: Thanks for having me. This is going to be a lot of fun.
[00:03:18] Carrie: Yeah. So I am really excited. I know we've never met until today in person actually virtually today, but I heard your conversation or your, um, your.
[00:03:31] Presentation at the sound foundation conference, which was just in March. And I was very intrigued both personally and professionally about your research in bi-modal patients. So I'm really excited to learn more about that today. But before we go into that, I always like to ask my guests, how did you get into the field of audiology?
[00:03:55] Rene: Yes. Great question. That is, I love to hear that as well. So mine is a little bit roundabout, as I think many of ours are. I started out as a pre-med, um, GRA know undergraduate student at Arizona state university. Um, I didn't really necessarily know why I wanted to do medicine. I just knew I loved the sciences and I particularly loved physics, um, as a high school student.
[00:04:16] So I knew I wanted to go down that path. And, uh, about two years into the program, I was really struggling to identify major, to go along with all those pre-med curricula and just, I felt like I was floundering. Um, didn't really love chemistry. Didn't do super well in it. And that's such a strong component of, you know, with the medical field.
[00:04:38] So I happened to just take a course in the department. Speech and hearing science at Arizona state, because I grew up next to a speech language pathologist, and I thought, well, let's try that out. You know, it's, it's, it's science, it's interesting. It's helping patients and my intro to communication sciences and disorders class.
[00:04:56] As soon as we got to the section on hearing. I mean, I was done. I just knew immediately. That's what I wanted to do. And it's so funny that it took me that long to figure it out because now here I am. Um, I'm nearly a junior undergrad. I did not have a major. And, um, the weird thing is I was raised by my grandparents.
[00:05:15] So my grandparents, um, from the time I was one year of age and my grandfather was a world war II veteran. He was in the 82nd airborne division a paratrooper and he received a purple heart. He had actually been shot down over the battle of Sicily and due to that, he had lost nearly all of his hearing in one ear.
[00:05:35] And he had a very steeply sloping, a precipitous hearing loss in the. So, as you can imagine, um, he struggled a lot. He was told for years by, you know, ENT audiologists, that there was nothing medical or surgical that they could do to help his hearing. And they were absolutely right at the time. Um, and then, you know, you tried number, hearing aids.
[00:05:55] Doesn't work so well for that type of hearing loss. And I just remember spending my entire life from the time I was maybe two or three. I remember having to grab a chin and kind of like moving it like, oh no, listen to me. I, you know, we're, we're talking now and having to, you know, really help facilitate effective communication.
[00:06:12] And so as soon as. Found this field, which I just absolutely love. Of course I was meant to do this. And, you know, and of course when my grandfather passed away in 1993, um, actually just before I switched to this major interestingly, and so I really felt like the timing was just absolutely perfect. And, um, while I wasn't able to necessarily help him and he wasn't able to get the, you know, the benefits that he needed during his life, I really sort of feel like this is me kind of giving back to, um, to them and, uh, for everything they did for me,
[00:06:43] Carrie: Wow.
[00:06:43] That's an incredible story of how like the little seeds in your life get planted over time and then it comes to fruition. So, wow. That's so heartwarming. And then, so then you ended up switching your major about your junior year and undergrad and decided audiology is your route and where you need to end up.
[00:07:05] So what was the next step then?
[00:07:08] Rene: Yeah, so what I knew I needed to, to pack my schedule, right. Because now when you're a junior and you're switching majors, I had to take a lot of prerequisites. Um, and so I took like the full 21 credit hours every single semester to make sure I graduated in four years. And one of the things I knew of course, we'd have to go to graduate school at the time.
[00:07:26] That was the master's degree. And so I knew I needed to start doing some volunteer work. Um, which I did anyways, but I hadn't done any in this specific field. So I, um, I did some volunteering work in Michael Dorman’s lab at Arizona state university. Who many of you know is, um, someone who has a long standing career in cochlear implant research.
[00:07:46] He's a speech scientist by training. Um, and I also did some volunteering in Bacon's lab who, um, the late physician, who is a psycho auditory condition who mostly focused on individuals with mild to moderate hearing losses, but very applicable, you know, hearing scientist, um, in the field. And so the interesting thing is, you know, I spent.
[00:08:06] Two semesters working alongside Michael Dorman as an undergrad. And it still didn't occur to me that I want to work in cochlear implant research until after my PhD. So I knew from there, I want to do research. I loved, you know, getting in there and playing around with like, When you form generators and looking at a scopes and checking on stimulate, and it just, I just loved it.
[00:08:27] Um, and so I, uh, did my master's degree audiology at Vanderbilt here in Nashville. Uh, went back to Arizona state, got my PhD, um, in the laboratory of David Bacon. So basic psychoacoustics normal hearing, mild hearing impaired, you know, like I, it was very, um, basic experimental psychology essentially. And then, um, The end of my PhD studies, I was having a conversation with Michael Dorman in the hallway.
[00:08:54] And he mentioned at the time he said, you know, there's this new surgical technique and there's this new implant where they're putting cochlear implants in patients who have. Good, low frequency hearing and they're able to preserve it. And now these people are listening with hearing aids and cochlear implants.
[00:09:11] And it was, again, one of those, like your moments where I knew, of course that's what I want to do. And, um, so I had about six months left in my PhD program. So I was finishing my dissertation, wrote a proposal to, um, look, you know, study these individuals and look at how they integrate electric and acoustic hearing coming from the same year and across ears.
[00:09:32] And, you know, I've never looked. So that was 18 years ago and I am still hooked on this, this topic and, um, just dedicate it to helping people hear better. Combining hearing aids and implants.
[00:09:46] Carrie: Wow. All of your undergrad and a master's experience and the people that you got to study under it really kind of drove you to this research and still involved in.
[00:09:59] And that's why I'm so excited to ask you these questions today, because from a very personal perspective and just getting a cochlear implant in 2019 and being a bi-modal recipient. And I think it's interesting to hear. Yeah. Search and then, uh, kind of reflect on my own personal experiences too, of what you find in your own research.
[00:10:20] And I'm like, yes, that's right. That's what, that's how I feel. So could you just share a little bit for our listeners today? Who might not know? Or can you just defined What a bi-modal, what bi-modal means.
[00:10:35] Rene: Yeah. So, um, by modal, I mean, it's sort of just a made up term, just means two modalities. And so in that particular concept, it typically is referring to individuals who have a hearing aid on one side, a cochlear implant on the other, but because it's just two modalities, technically it could also apply to individuals who have acoustic hearing preservation in the implanted ear and are combining electric and acoustic hearing that way.
[00:10:58] But that's not typically, usually when you see the term bi-modal it's meaning, you know, electric only on one side. Acoustic only on the other.
[00:11:06] Carrie: And so you've said you've been doing this research for about 18 years. And so what have you seen over time from that beginning of the 18 years till now?
[00:11:19] Rene: Oh, it was just so much fun.
[00:11:20] Yeah. So, um, in the beginning, I agree, this predates me a little bit, but I remember when I was a master student at Vanderbilt and we would talk to people who were getting, you know, interested potentially in cochlear implants, which was a very small proportion of our patients at that time. Um, but the advice that was given by most centers at the time was, you know, if you have a hearing aid that you're still wearing on the other side, It's recommended that you stop wearing that because you know, the brain's not going to know what to do with these two very distinctly different signals.
[00:11:51] And we need to really strike them that auditory pathway on the newly implanted side. But people started to learn pretty. Well, I wouldn't say quickly, but you know, over a course of about a decade that there weren't any data that were really driving that clinical recommendation. And so, and a lot of people started to notice, you know, when I wear my hearing aid, I'm actually feeling like I'm hearing better.
[00:12:13] I'm utilizing that more natural sound, quality, the acoustics of, you know, the lower frequency speech that I can't necessarily get from my cochlear implant and, um, the research and bi-modal hearing. And, uh, you know, bi-modal auditory perception really started to explode in the early two thousands. And it was quite clear from that point forward that, of course, this is what we should be recommending, you know, we should absolutely be ensuring our patients are using all of the hearing technology that potentially can improve their outcomes.
[00:12:42] And of course, most of this in the early days was pre bilateral. Um, in fact, I remember in my postdoc, there was talk amongst the lab that, Hey, there's a new bilateral cochlear implant recipient in California. We should try to get them to come into the lab. Like it was, you know, like one in the world kind of thing.
[00:13:01] And, um, and then you'd hear of another and then another, and then, um, It was exciting, but, um, so I got to sort of witness the, you know, the evolution of hearing preservation, cochlear implantation, widespread adoption of bi-modal hearing, as well as the, um, the adoption of bilateral cochlear implants and the transition to that being sort of considered the standard of care.
[00:13:26] Carrie: Yeah, so that I have so many questions, but I guess my first question would be about bi-modal and bilateral. And that what point from a research perspective, a clinic perspective, are you recommending or starting to plant that seed with patients? Okay. Didn't, you know, bi-modal might be your way to go or bilateral might be a better way to go.
[00:13:51] Rene: Yeah. So are we focusing primarily on adults right now? I
[00:13:55] Carrie: would like to start with, let's start with adults.
[00:13:58] Rene: So with adults, obviously, um, it's our goal to always talk about really what's the appropriate or the recommended intervention for each individual ear, right. Because we want to make sure that we're optimizing that hearing for that individual.
[00:14:11] So, um, we typically. From the minute I see them in the cochlear implant clinic, I'm going to assess each year individually, uh, with, you know, air audiometry speech. Audiometry. And then of course, with fitting, you know, the appropriately fitting hearing aids and looking at eight at speech recognition on both sides, as well as in the bilaterally aided condition and right from there, if someone technically meets the criteria for a cochlear implant in each year, we're going to discuss that.
[00:14:37] I'm going to say, you know, to that individual, you know, look, it looks like you really do meet the criteria for both ears. However, we do often recommend unless someone has, you know, profound hearing loss across all frequencies. Um, it has an, or had a very sudden onset. We definitely in the adult population are recommending that people start with a single implant and utilize the bi-modal hearing configuration because there's tremendous amount of benefit.
[00:15:04] Um, as you know, You know, that hearing configuration, having the ability to, uh, combine what you can't get from the implant, with what the implant really does a great job, which is audibility across the entire frequency spectrum. And, you know, the brain is just a remarkable, um, it's just remarkable organ and it has it's, you know, we see this neuroplasticity that happens very rapidly following activation of the device and having.
[00:15:30] Low frequency, more natural sound quality from the hearing aid ear really helps sort of drive their ability to use that new found signal. So that's kind of what we recommend, but we also sort of make sure that they know really from day one, that technically both of your ears are considered candidates for an implant, but we're going to start with this hearing configuration and then we'll readjust, or, you know, kind of reassess in, you know, 3, 6, 12 months.
[00:15:58] Um, and then of course, many of our adult patients retain that bi-modal hearing in fact about 80% of our adult population, at least at Vanderbilt, um, does retain bi-modal hearing. They, they just do so well with that combined configuration. Um, but it's the flip side on the pediatrics, our pediatric population.
[00:16:16] It's more like 80, 85% are bilateral and then the rest are bi-modal.
[00:16:21] Carrie: Okay. So though, a point maybe going back to adults where. Maybe an adult, like after 3, 6, 12 months, do they say, you know, the hearing aid, I take it off and I don't really use it that much. Is that kind of a tipping point where you're like, maybe you might want to consider bilateral cochlear implants.
[00:16:44] Rene: Yeah. So it definitely, I would say that a lot of the times it's patient driven, which isn't necessarily a bad thing, which I'll get to in a moment. But a lot of times I can sort of almost tell what, which path someone's going to go from that one month appointment. So I'll have some people who come in and they immediately go, okay, let's start talking about when we're going to get the second implant.
[00:17:03] You know, they just, they just know like, and these are often people who were very adamantly against it in the preoperative time point. Um, whereas some people will show up, you know, for that one month appointment. And they'll say, you know, I'm just shocked at how well I'm able to, you know, use the information from these two signals.
[00:17:19] You know, on the first day it sort of felt like I was hearing these. It's almost like two different. Uh, you know, completely different sounds and now it sorta sounds more natural. And so those are the people I started to say, okay, they're really adopting this technology. They're doing really well with it.
[00:17:34] We'll continue to assess. And of course, if hearing is lost in the non implanted ear, or if that ear, you know, is the speech perception drops dramatically, we might have a different discussion, but, um, we do tend to find that our patients are. Very, um, they're very good at identifying what they need. Um, in fact, uh, Michael Dorman and I have a paper that we published in 2019.
[00:17:58] Well, we looked at, I mean, close to a hundred people, um, that were broken down into bi-modal adults and bilaterally implanted adults. And we looked at the bi-modal adults and we basically did all of these tests on them. Laboratory-based tests, spatial release from masking speech perception, all these different things, um, in an attempt to try to figure out when would it be best to recommend that someone definitely, you know, pursue that second implant.
[00:18:25] Well, we didn't really find that there was anything dramatically, um, useful, at least not on the clinical measures. We found some, you know, more laboratory-based measures that you use multiple loudspeakers. Um, however, the one thing that was very, very sensitive and, um, was really highly correlated with the laboratory measures was asking him a simple question, which was, do you think you need a second implant?
[00:18:49] Okay. If the patient said yes, I think I do. It was more likely that yeah, they were actually not showing great benefit from that bi-modal configuration. Whereas those that said, no, I think I'm doing well with my current technology. They were absolutely right. So I think that that just kind of really reinforced my, um, what I kind of thought all along.
[00:19:10] But, you know, patients really do know what's best for them, for the most part, and really want to listen to them and take their guidance.
[00:19:18] Carrie: So on the flip side, that thinking about it. Good. And kind of, you said, you know, about 80, 85% bilateral cochlear implants and only about 20% who stay bi- modal. Is there a different, I guess criteria?
[00:19:33] Yeah, a thought process when you're looking at bi-modal versus bilateral for kids. Oh, I
[00:19:39] Rene: love this. Yes, there is. So, as you mentioned with pediatrics, the indications for cochlear implantation are actually quite different than they are for adults. And so on the pediatric side, at least the FDA labeling specifies profound, bilateral sensorineural, hearing loss, um, or severe to profound for children who are two years or older
[00:20:00] So that's in contrast to the labeled indications for adults where both cochlear and Medicare specify, moderate sloping to profound for adult, um, you know, bilateral sensorineural hearing loss. So we're already dealing with a population that has much more severe hearing loss for the most part. Um, on the pediatric side.
[00:20:20] Um, now granted we do get some children that are referred in that are more kind of, non-traditional maybe a little off label, better hearing in the low frequencies. And we're certainly trying to expand that referral base because we know a lot of children in that particular category would do better with a cochlear implant.
[00:20:37] But the reality is it's. Pretty, uh, you know, small proportion of our patient population on for our children receiving implants. So that's one of the reasons that we typically the children that we see are presenting with bilateral severe to profound sensorineural hearing loss, for which we know that bilateral cochlear implants is absolutely going to be, you know, standard of care, giving them the best option for maximizing their auditory potential.
[00:21:01] Carrie: Yeah, that makes, that makes a lot of sense. It'll just be interesting with your research moving forward. And I know we kind of always start with adults and see how they do, and then it kind of trickles down to the pediatric population, but what would this conversation be? Five or 10 years from now when absolutely about pediatrics.
[00:21:20] Yeah, I, I,
[00:21:21] Rene: I really, I, I, one of the big goals of my career is to expand criteria for pediatrics, because again, we, there are, there's a growing literature base of children who are, you know, better than severe to profound in, um, in the implanted ear and who are just, you know, they're deriving tremendous benefit from this cochlear implant.
[00:21:40] And so my goal hopefully is to really, if we can't get the labeled indications changed, if we can get more and more providers, you know, ENT audiology, To refer those children in for an evaluation, because that's the thing. I think a lot of providers are really more reluctant on the pediatric side to recommend someone because they might be getting some benefit from their hearing aids, but maybe it's not going to be the amount of benefit they could get when paired with a cochlear implant
[00:22:07] Carrie: Yeah. So do you see any disadvantages that you found with bi-modal patients or here.
[00:22:17] Rene: Yeah. So there are, there are a few, um, some disadvantages for bi-modal hearing and it's primarily related to more spatial hearing in general. So, you know, I'm, I'm kind of a binaural person. That's the thing I'm really interested in, in my research and the cues of course, that we use to orient, to sounds in our environment, to, you know, for spatial abilities.
[00:22:38] Interaural level difference cues as well as interaural time difference cues. So of course, sounds are hitting our head at various different times from where they were oriented in space and we are primarily using interaural time difference cues for lower frequency sounds and interaural level difference cues for higher frequency sounds.
[00:22:59] Now, the here's the thing though, is that. interaural time differences. We need access to bilateral acoustic hearing to be able to take advantage of those because our nervous system, our neurons have this ability to sort of fire on about the same phase of an incoming stimulus and it's called neural phase locking.
[00:23:17] And that allows our system to basically, um, identify immediately what's the, uh, where the sound originated from. What's the frequency of that sound and our it's just it's like instantaneous. Okay. The sound originated from the right and it was someone. Yelling my name. So immediately when you have bilateral cochlear implants or bi-modal hearing, you don't really have access to the interaural time difference cues because the cochlear implants don't preserve that fine timing information in their envelope based signal process.
[00:23:47] Um, so what they can use is interaural difference cues, which are most robust in the higher frequency region. Now they're present in the lows, but it's, you know, a few DB in magnitude, whereas at four and eight kHz, we're talking like 20 or more DB of a difference across the ears. And so bilateral cochlear implant recipients have access to ILD because they have high frequency audibility in both.
[00:24:13] Yeah. Whereas if you're bi-modal the typical bi-modal patient has, you know, good audibility across all of the frequencies in the implanted ear, but the non implanted ear tends to have a sloping hearing loss for the most part. You know, some people have flat losses, but with those sloping losses, we're just kind of getting audibility in the non implanted ear.
[00:24:34] And so that leaves that individual without, you know, a good ILD, um, sensitivity. And so what we found is that individuals like that do tend to struggle a little bit more in us, you know, localization where a sound's coming from spatial release from masking. Um, as well as in conversations where, you know, this has been a while since we're coming out of a pandemic, but think about being like at a, you know, a holiday party or at a, you know, group dinner.
[00:25:01] This person talks and then someone across the table and the other side interjects, and then this person over here, and you'd have to sort of follow that conversation. Um, that's going to be a little bit more difficult to do in a bi-modal hearing configuration where we don't have access to those high frequencies.
[00:25:17] Um, but you know, the nice thing is we, we know, um, that where we need to kind of sit and orient ourselves in conversations to optimize the hearing abilities that we have. It's just that. It's less of a need to do that when you have bilateral cochlear implants or bilateral acoustic hearing. So, you know, for example, in cases of cochlear implantation with acoustic hearing preservation, which of course is another great love of mine.
[00:25:45] Carrie: Yeah. Well, those are some of the things that you said. I feel like I'm experiencing now as a bi-modal user. And just for example, of like being in a more noisy kind of place. Kind of situation. I noticed that I really have to focus more on, you know, okay. You need to be on my good side. Do I need to really follow the conversation in that respect too?
[00:26:11] And I think what I've noticed. The most is, I feel like I have become more of a unilateral, um, user, because my implant side, like you said, gives great audibility across all of the frequencies. So that seems to be my more, that my stronger ear. But then I love my hearing aid side, but the acoustic aspects that you were talking about, so that natural aspect of speech.
[00:26:37] Um, but yeah, I never before would like tell my husband, like, you need to walk on this side of me, not on this side. And now it's like, he's like, oh wait, like, which side is which side should I be on now? So kind of this whole other evolution, you shouldn't have a conversation that we have to go through.
[00:26:56] Rene: Yeah, that's a great, I love how you brought that in.
[00:26:58] And that's, that's the one thing, you know, we found in this paper from 2018 that, um, we looked at a group of bi-modal adults and a bilaterally implanted adults. Um, they both performed very similarly. It's just that when speech was roped randomly, you know, from like zero or plus, or minus 90, when it was over to the poor ear, which for the most part was the hearing aid ear.
[00:27:19] Right. Our bi-modal participants were at a significant disadvantage, whereas bilaterally implanted adults, it's almost like they didn't have a better ear, you know, so, you know, preferential seating and sort of organizing where I'm going to stand relative to others just is not as much of a concern when you have bilateral.
[00:27:37] Carrie: Yeah. It's like, do you give up something to gain something to trade. Which I thought I would ask? Uh, just another question that has to go along with bi-modal users. Do you feel like programming? Um, the cochlear implant and the hearing aid are the different. Techniques that you utilize, or you have found that help.
[00:28:01] I don't want to say even it out, but kind of, uh, make sure that they compliment each other.
[00:28:07] Rene: Oh, great question. Yeah. For the most part. No. So there's a lot of, um, there's been a few studies that have come out in the last few years that kind of looked at, you know, what's the best way to program the hearing aid for someone who's listening by readily.
[00:28:19] And the reality is there's no real evidence that, you know, for example, NAL and a one versus versus DSL for adults, or it's sort of like, if you can just make sure that you have audibility in the frequency region over which they have the capacity to have audibility. That's going to give them the benefits.
[00:28:38] So that's, you know, I, I sort of, don't worry too much about picking one particular, you know, target. However, one thing we have found and it's in a relative minority of individuals, but we, um, in the lab, we routinely check for cochlear dead regions and then anytime there's acoustic hearing. And so if people are not necessarily familiar with that, it's just, of course, as you know, a region of the cochlea where there's little or no surviving inner hair cells So, um, so basically if you try to provide, you know, acoustic transmission, that range, it's just not gonna make it to, uh, those primary auditory neuron, because there's no inner hair cells, which are the primary afferents, um, in the auditory system.
[00:29:17] So, um, what we have found is that when patients have a region of cochlear dead regions, but yet we still have, you know, aided or we still have unaided audiometric detection there, which is of course, for the most part due to off frequency listening. Because we're just providing a we're driving that basilar membrane, and providing a lot of a high sound level that they can hear on the tip of the tail of that traveling wave.
[00:29:42] Um, but when we, when I see someone who has a very, you know, distinct cochlear dead region, we do start to play around a little bit with maybe restricting the frequency region of the hearing aid ear. Um, and we do have a paper that came out. I don't know about five or six years ago where we looked at a group of people.
[00:29:58] And when there were a cochlear, dead regions, and we restricted the frequency region, we did see a significant improvement in their ability to combine across those two ears. Whereas if the patient didn't have a dead region, And where you restricted the frequency region. They didn't show a benefit.
[00:30:16] And in some cases they showed a detriment in their performance. So I don't recommend this as kind of a blanket thing that we do for everybody. You know, like for example, all right. Anybody who has a threshold of 80 dBHL. Don't even try to amplify it. We don't do that. So we look and see really, is there a region where there's little or no surviving inner hair cells?
[00:30:36] And if so, we do experiment with restricting that range. And I've seen in some cases where you see acute benefits, you know, so we'll restrict the hearing aid, um, frequency response, and then put them back in the sound booth and their performance goes up dramatically. We typically, you know, we don't see that all the time.
[00:30:55] Um, but often in those cases we also see dramatic reports of improved sound quality. So that's something that I think could really be value added in our clinical audiology practices.
[00:31:07] Carrie: Yeah. I was just always curious. Cause we were playing around with my different hearing aid settings too. Just to see if there is one that kind of complemented or I felt like it complimented better than the other and it was just, just trial and error.
[00:31:24] Okay.
[00:31:25] Rene: Cause I really love to hear if there was anything specific that you felt really worked well in that configuration.
[00:31:31] Carrie: Yeah. No, and I. My, I don't want to say problem, but the, you know, technology and, and growing up with hearing loss, I mean, I was initially with analog power hearing aids, so I've always been a very much of a, more of a.
[00:31:48] peak Clipping, um, analog music. So like my switch to digital hearing games was very hard. So I don't know. I think I make sense of a lot of distortion of information in order to have more clear signal that if somebody was getting hearing aids today for the first time you would program it a lot differently.
[00:32:10] Sure. Right. Yes. So, so kind of going, um, back just a little bit. I would love to hear. More about your research and your experience with hearing preservation. Yeah. So
[00:32:26] Rene: I, this is something I just feel so strongly about and love so much. And, um, so I, thankfully, you know, I'm at a center where all of our surgeons really approach every surgery as if it were hearing preservation surgery.
[00:32:40] So, I mean, the goal of that of course is minimally traumatic, you know, surgical approach. Um, for example, limited drilling and. So using the round window, if at all possible for electrode, insertion, um, and, uh, you know, really kind of picking and choosing the, the cochlear implant electro array that you would use based on the patient's own anatomy and approach.
[00:33:01] So, um, so thankfully, so I remember back when I first started my post-doc in December of 2003, you know, the, the men or people. In the world, but here in preservation, I mean, you could probably count it on, you know, your hands. Um, and at that, at that time, most of them were in Europe where, you know, they weren't sort of regulated by, um, FDA.
[00:33:23] They had their own guidelines, they could do their own thing. Um, and we have a handful in the U S particularly those coming out of the university of Iowa because they had the hybrid clinical trial there. And, um, So I went from seeing, you know, hearing preservation patients who were, you know, very, very few and far between and hearing preservation rates being pretty low, you know, because this was a new technique and this was a new way to think about, um, cochlear implantation and, and, you know, audiologic, and otologic management of our patients to the point that now we've looked and we're getting, like, seeing that, you know, up to 90 to 95% of people who have hearing going into surgery, Do you have some degree of preservation postoperatively now not everybody's going to have usable or functional acoustic hearing preservation, but it is just so exciting to see that, you know, the, the electrode arrays are less traumatic.
[00:34:15] The surgeon, you know, the surgical techniques are improving. Um, we're learning more about the use of steroids for anti-inflammatory anti-inflammatory responses and, and potentially helping. You know, that preservation and the benefits that we see from just combining that acoustic hearing in the implanted ears.
[00:34:34] And I say yours because we know about, you know, more and more people are getting two implants and have acoustic hearing preservation in both ears, but it is just such an exciting thing. And to see that all three of the FDA approved systems have integrated EAS technology. Yeah, yes. Technology, you know, which allows like a hearing aid and an implant processor in one, it's just something I would have never, ever, you know, even dreamed of when I first started working in this field, um, you know, we used to split them with its along with the behind the ear, sound processors and talk about cumbersome.
[00:35:08] Um, and, and now it's just, you know, a Ric system or an ear mold on the middle system. There you go off you go. It's it's just, I just love it.
[00:35:19] Carrie: Yeah, it's amazing. And then your point about, from a patient perspective, I love the fact that. Even though it's not per se usable speech hearing, but to have awareness of sound when I don't have a device on is really powerful, like at night and you know, I wouldn't, I can still hear the dog bark, so it's different low-frequency information.
[00:35:45] And I know that's going to be different depending on the amount of hearing that is preserved, but to have that awareness is kind of. I guess, I don't know. It just. More like a safety net for
[00:35:58] Rene: me oh, absolutely. That's I mean, that's a big deal and I can understand, especially when you go for example, to bilateral, right.
[00:36:06] Because one of the things, you know, I did mention we're up to 99 to 95% of people being able to have hearing preservation, but that's not necessarily for the longterm and it's not something that we can guarantee, you know, everyone's body and physiology has a different sort of. Uh, an inflammation, response to surgical trauma and, and, um, and that, and so we just can't, you know, reliably predict who's going to have hearing preservation.
[00:36:31] And like you said, I mean, there's definitely a safety component and, and just sort of peace of mind in general, right? Like you said, you take your processor off, you can put earbuds in, you can hear your dog barking, you can. It's just, you know, you don't have to necessarily rely on just one side and make sure you hear one.
[00:36:47] Cause you got hearing in both years. So I think that's, you know, it's something that we. Um, I definitely appreciate when we're making these, you know, clinical recommendations to our patients and something that I know myself I would want to have as well.
[00:36:59] Carrie: Yeah. I mean, that was certainly something that when I was making the decision was a plus, um, knowing that, Hey, there's a possibility that you can still have hearing in that ear.
[00:37:11] And it helped a lot with that decision too. And yeah. Yeah. So, um, one other question that I kind of had, we were talking at the beginning about how your brain is so amazing and it can integrate that acoustic signal on that electric signal. Is there anything that you, or at Vanderbilt that you are recommending and for your patients to help drive that integration a little bit quicker, uh, so that your brain adapts to those bi-modal signals?
[00:37:44] Ah,
[00:37:45] Rene: great question. Yeah. So there is actually, and it's nothing that's particularly exciting or fancy it's, um, it's just wearing the devices. And so, um, one of my colleagues, uh, Dr. Jordan Holder, who's now, um, on faculty at Vanderbilt, um, for her dissertation, she was looking at. Basically the, the causal, the potential of a causal relationship between cochlear implant, wear time, which we get from data logging with our, with our cochlear implant systems and how much benefit one would get on measures of speech understanding.
[00:38:17] And for years, you know, we, you know, as audiologists, we've told people for years, you know, you have to wear your, your devices. That's the only way you're going to get better. Eyes open ears on that sort of thing. Um, but we didn't, you know, it made sense at face value, but we didn't necessarily have evidence to support that.
[00:38:33] And then about 20 years ago, uh, hearing aids came out with data logging capabilities, and we realized that people weren't wearing the hearing aids as much as they had, you know, suggested they had been. Um, and then later on, we got data logging in, in cochlear implants and then a number of studies have come out as you know, that have shown this correlation between.
[00:38:52] You know, average daily wear time and auditory performance, but we never really knew, is this a, is this a chicken or an egg thing? You know, is it something like someone who gets their implant and does well, of course they're going to wear their implant longer or is it really, they wore their implant longer and they're doing well.
[00:39:08] So, um, as part of Jordan's dissertation, she, um, brought in a group of adults who had all been using their device for a minimum of. 12 months. So these are people, you know, experienced cochlear implant users, and they all had to be wearing their devices less than 10 hours a day, so that there was room to sort of improve, right?
[00:39:26] Because if they came in wearing the device 16 hours a day, we wouldn't want them to sacrifice sleep time, you know, just to improve their, or increase the wear time. So they were all instructed to wear their cochlear im;ant as much as possible. But the goal was for them to increase their daily wear time by a minimum of one hour.
[00:39:45] Minimum. So, um, with these 20 people, uh, she did find a significant correlation. And in fact, she saw that for every one hour you can improve or increase your daily wear time that translates it to a seven percentage point improvement for sentence recognition in noise. Which is the most difficult situation that we have.
[00:40:06] Right. So to put that into a little bit more clarity, so let's assume that someone came in wearing their implant 10 hours a day, and they were able to increase to 15 hours a day, which would be close to, you know, kind of all, all day, um, that person would be expected to improve. 35 percentage points for speech recognition in noise, which is quite dramatic.
[00:40:29] And it was also shown that it, we believe anyways that the, you know, the, the driving mechanistic factor might be their ability to, um, parse out the individual frequency components of that signal and something that's happening from like a neuroplastic, you know, compensatory, neuroplastic perspective. So, um, so Jordan Holder's going a little bit more down that road.
[00:40:52] Kind of, you know, investigating a little bit more of the causal link and I'm going in a slightly different direction and really trying to describe those neuroplastic changes that are happening from a audio and visual perspective, following cochlear implants, uh, and we're using, um, a relatively newer tool functional near infrared spectroscopy or , uh, to look at this and, um, pediatric and adult cochlear implant patient.
[00:41:17] So you have to stay tuned, but yeah. Um, where it gets your, get your hearing aids, get your cochlear implants and wear them as much as possible.
[00:41:26] Carrie: And do you ever recommend, like, even just for a therapy kind of perspective, just listening with the cochlear implant, just so that your brain is like, okay, this is what that signal is.
[00:41:37] Rene: Absolutely. Yeah. So this is one of the things another where we recommend, you know, auditory training or rehab at could, because at face value, it makes sense. Um, but similarly, we don't have a lot of, um, evidence in the peer reviewed literature anyways, that is really, you know, rigorously investigated the effectiveness.
[00:41:57] A specific or type of auditory training, at least in the adult population. Now, of course, that doesn't mean it's not a good thing to do, but I definitely think we as audiologists and hearing scientists and otologist, we really could stand to benefit from, you know, rigorous prospective studies that are looking at the effectiveness of various different types of auditory training, uh, dosage.
[00:42:20] So is once a day for an hour. Good enough. Do you need more maybe? Just a few hours a week is enough. Um, and really to identify because, um, you know, in many other areas of the world, our auditory training is just considered a given when, you know, even when adults get cochlear implants and in the US we don't really necessarily do that.
[00:42:40] For better or worse, but, um, you know, I would love to see the outcomes of, of some studies that have looked at that because it's, you know, I can say that anecdotally, at least the patients of mine who commit to doing this do tend to be my better performing patients. But again, is it a chicken or egg thing they're doing better?
[00:42:58] So they're motivated to do these exercises versus those who are struggling and they say, yeah, forget it. So,
[00:43:05] Carrie: yeah. Yeah. From my personal perspective, I think we, we definitely need more work in that area. And I think for me, at least, I was just blessed that I had a therapist who was one of my professors when I was in grad school.
[00:43:22] And I have kept in touch with her, but she was an auditory verbal therapist. So she said I would love to work with you. And so her name was Dr. Denise Wray. And so we, we have just been meeting like on kind of a weekly or biweekly every other week basis. But I think from a patient perspective, especially at the beginning, it was.
[00:43:46] Almost that coaching perspective of being like, okay, she's documenting this and she's seeing the little small changes. Again, motivated me to be like, okay, I'm going to continue this on my own. So that next time I see you, I might perform better. So it was almost for me that coaching auditory therapy was a huge component of me kind of mixing, you know, getting the signals together.
[00:44:15] That's the other thing. Yeah. The other thing that I love to do. And I just coined it, my, my own name and I call it bi-modal switching. So I like to sit outside and just kind of be mindful of what's going on in the environment and just flipping my magnet off my head and listening and just kind of taking them.
[00:44:38] You know, what's happening in the environment and I'm putting the magnet back on and seeing what sounds end up coming in. And so I don't know, it just, for example, like sitting on the porch and hearing the wind chime when I take the magnet off, the wind chime was gone when I put it back on, it comes back.
[00:44:57] So it just kind of brings in. Well, it makes you aware of what you're listening to with your hearing aid only, then what you gain with your cochlear implant in that situation. So,
[00:45:11] Rene: yeah, I mean, that's like, you're, you've sort of inventing your own like perceptual training, um, types of paradigm, right.
[00:45:17] Where you're sort of. Okay. I'm going to teach my brain that this is what I gain when I add the implant to my acoustic hearing. I love that. Is that something that you would recommend to, to patients who are, um, pursuing cochlear implantation?
[00:45:32] Carrie: I would. I call it bi-modal switching and I think it just lets you.
[00:45:38] Experience everything that you haven't heard and jotting down those different sounds that you hear and, and, um, experience on a, on a daily basis. So another motivation tool, I think
[00:45:52] Rene: too. That's great. Yeah, I might, I will, of course cite you on that, but then encourage my patients to also journal, you know, to say like, what is the additional added benefit that you get?
[00:46:02] Because you know, it really makes them more mindful of the process.
[00:46:06] Carrie: Exactly. So this was an amazing conversation. I'm so glad that we're able to have this today. Is there anything that I didn't ask you that you're like, I want to make sure that listeners hear about this.
[00:46:20] Rene: Yeah. So the only thing I think I would want to just say is that, um, we are still at, you know, on the adult side, we're still only getting about 5% of people who actually could benefit from a cochlear implant are getting them.
[00:46:33] And, um, you know, we just, as we have to do better at getting more people in and taking advantage of this really life-changing technology that could really benefit another thing. When we tend to see at least on the adult side, when someone actually initially presents for a cochlear implant evaluation, for the most part on average, that patient has been a candidate for 10 to 12 years.
[00:46:55] So again, you know, we get this one shot to do this, and I really want this. Take advantage of this and in getting these referrals in much, much more earlier than they're doing right now. Um, the second thing of course is that I want to see more and more referrals of people who have, you know, residual hearing in the lower frequency region, because as you said, you know, we can.
[00:47:16] We are actually able to preserve acoustic hearing, um, in most cases, most cases. And even if we don't, which of course is not our goal, but you can still combine that electric and acoustic hearing across ears in a bi-modal configuration. And I can tell you that I have not met a single person who has said, well, I really regret getting this.
[00:47:35] You know, it's almost like as soon as they get it, they say, why didn't I. Five 10 years earlier. So that would be my recommendation. Um, and, and then third, let's get more and more children in the door who have maybe these non-traditional, you know, hearing losses, non-traditional cochlear implant candidates. If a child is struggling to, um, for, you know, with socialization in, in school and, and understanding and various different, um, listening environments dependent on their FM or their, you know, remote microphone system, uh, and really struggling.
[00:48:05] Um, it has speech production, um, delay. I say that it's at least worth a referral. We might not necessarily recommend a cochlear implant to start, but it's, it's getting that conversation started with that family so that we can really be helping more and more people than we are.
[00:48:21] Carrie: Yeah, no, those are all great ending points.
[00:48:23] And I agree 100% that the referral process shouldn't be thought of as a last resort. And I think that's where a lot of our, especially in the adult population, if they're seeing an audiologist who is fitting for their hearing aids, maybe that audiologists doesn’t realize that the cochlear implant process continues to, uh, I guess candidacy continues to change and.
[00:48:48] It takes, I mean, I know it takes a while to make that decision. So if we don't start planting the seeds a lot earlier and having that conversation a lot earlier than that, that delays the process too, because from a patient perspective, you still need to go through all of the emotional journey that it takes to get to that decision-making process.
[00:49:08] Rene: Absolutely. I, you know, I was encouraged from the moment hearing loss is diagnosed. Start having the conversation. This is the hearing healthcare continuum. We start with hearing aids. We have additional, you know, um, FM remote microphone systems. We might transition to various different types of auditory implants.
[00:49:24] Like you said, it's not a failure. It's not a last resort. It's just one of the options on that continuum.
[00:49:31] Carrie: Well, thank you Rene for coming onto the empowEAR Audiology Podcast today. It was a great conversation and I really appreciate your time today. Thank you.
[00:49:42] Announcer: This has been a production of the 3C Digital Media Network