Wideband Tympanometry in Adults with Severe to Profound Hearing Loss with and without Cochlear Implants
, Chamutal Efrat 1,3, Brian Westerberg 4, Jane Lea 4, Eytan David 4, Ofir Zavdy 5,6 and Ohad Hilly 5,6
Round 1
Reviewer 1 Report
This is another nice research work from this group that continues the research of possible inner ear changes reflected in WBT measurements.
In general, the authors compared WBT results of normal adults to adult patients on ears with and without CI. They also investigated the immediate test-retest reliability of the WBT in all 3 groups.
Results replicated previous data which showed that CI causes a reduction in absorbance of lower frequencies. Here, the difference in implanted and non-implanted of the same patient strengthens the findings.
The rationale for possible mass and stiffness changes in SNHL is reasonable and supported by previous research findings. However, the primary concern is the chosen groups' ages.
Since the normal hearing participants were relatively young (M=25.14) and the patients were much older (M=55.82), the comparison could be influenced by age and not by the SNHL factors. The authors referred to this limitation however since this is the major novelty of this study, it is difficult to rely on the current data without recruiting matched adults of the same age with no SNHL. Otherwise, it can only serve as preliminary results and finding which weakened the study's novelty.
Another concern I have is the no report of no BC thresholds; why is this data missing? It was stated that in 2 patients with BC, no ABG was found. In previous studies, Raveh et al. showed low-frequency ABG, so why wasn't it appear in this study? Moreover, in Raveh et al. a possible tactile sensation was not even mentioned in the entire manuscript. It is very common to have such an ABG because of tactile sensation and not actual middle or inner ear etiology.
Other comments:
Line 147 - 0.6-1.6ml and not 16ml
Line 147 - ipsi or contra reflexes?
Line 153 - with which DPOAE machine was it recorded?
Line 203- dB HL and not H.L.
Line - 397-398 Pressure settings (peak and ambient pressure) had insignificant effects on the results, which is not surprising given that almost all ears had normal middle-ear pressure. In normal ears,
the results lines 350-353 - The highest order of the interaction pressure by frequency by condition was significant (F(30, 1185)=6.1965, p=0.0000) and remained significant after G-G correction. This indicates that the power absorbance (P.A.) in normal ears, non-implanted ears, and implanted ears varied differently across pressure and frequency.
So there is an effect of the pressure between groups? why? The author should explain it in the discussion.
Line 380-383 and line 411- What is the reference for the middle ear resonance at 1600Hz? How was it measured? I believe that other authors found that others that used the Titan found different resonance frequencies in the normal ear:
https://www.advancedotology.org/content/files/sayilar/88/buyuk/157-1621.pdf
https://link.springer.com/article/10.1007/s00405-020-05909-9
Lines 424-430 - I don't see any reason to use a self-citation of research conducted on animals. At the same time, there is a handful of research on SSCD in living humans, cadavers and human temporal bone (Merchant, Rosowski, Roosli etc.)
Author Response
We would also like to take this opportunity to thank the reviewer for his invaluable comments and inputs. Please find below our reply to each comment of the reviewer.
We hope that now the article is suitable for publication in the journal.
Authors
Reviewer 1:
Comment 1: "However, the primary concern is the chosen groups' ages. Since the normal hearing participants were relatively young(M=25.14) and the patients were much older (M=55.82), the comparison could be influenced by age and not by the SNHL factors. The authors referred to this limitation however since this is the major novelty of this study, it is difficult to rely on the current data without recruiting matched adults of the same age with no SNHL. Otherwise, it can only serve as preliminary results and finding which weakened the study's novelty".
We have edited this section in the discussion to reflect this limitation better (lines 523-531). Moreover, we have stated in the conclusion that “In conclusion, cochlear implantation can affect middle and inner ear mechanics and absorbance patterns in WBT. Based on our study design and the use of two control groups – hearing impaired non-implanted ears and normal hearing ears – we propose that a lower significant absorbance at 400-800 Hz and higher absorbance at 1600 Hz are secondary to the implantation. Lower absorbance at high frequencies (4000-5000 Hz) can be associated with aging or SNHL.”
comment 2: Another concern I have is the no report of no BC thresholds; why is this data missing? It was stated that in 2 patients with BC, noABG was found. In previous studies, Raveh et al. showed low-frequency ABG, so why wasn't it appear in this study? Moreover, in Raveh et al. a possible tactile sensation was not even mentioned in the entire manuscript. It is very common to have such an ABG because of tactile sensation and not actual middle or inner ear etiology.
Response: Thank you for your excellent remarks. We have clarified this issue in the method section. The CI group participants were recruited from an existing pool of persons with CI at the Saint Paul’s Hospital implantation centre. Since all participants were already implanted at the time of the research, pre-operative audiograms were obtained from each patient’s file. For four of the participants, no pre-operative audiograms were available; however, even for them, there was no indication of a conductive component in their medical history, surgical reports, or imaging, as well as in their clear Otoscopy results obtained by the ENT surgeon. In all these audiograms there were no measurable BC thresholds due to the severity of the loss and instruments limitations. We have also indicated that the BC thresholds are likely due to vibrotactile sensation in the two CI participants with BC thresholds at low frequencies (lines 177-182).
Other comments:
Line 147 - 0.6-1.6ml and not 16ml
Fixed
Line 147 - ipsi or contra reflexes?
Ipsi was added
Line 153 - with which DPOAE machine was it recorded?
The system was added. Titan Interacoustics with WBT and OAE module
Line 203- dB HL and not H.L.
Fixed
Line - 397-398 Pressure settings (peak and ambient pressure) had insignificant effects on the results, which is not surprising given that almost all ears had normal middle-ear pressure. In normal ears,
We are not sure what reviewer is requesting as this is a direct quote from the manuscript
the results lines 350-353 - The highest order of the interaction pressure by frequency by condition was significant (F(30,1185)=6.1965, p=0.0000) and remained significant after G-Gcorrection. This indicates that the power absorbance (P.A.) in normal ears, non-implanted ears, and implanted ears varied differently across pressure and frequency.
So there is an effect of the pressure between groups? why? The author should explain it in the discussion.
Response: Thank you for your excellent point here. The main effect of pressure was not significant in each group likely due to minimal differences in the tympanometric peak pressure. However, the interaction between the groups frequency and pressure was significant which may indicate that while within each group the effect of pressure was not significant but between the groups, the differences in absorbance between the ambient and peak pressure across frequency was not similar. We are not sure the clinical relevance of this finding but we have indicated that in the discussion section.
Line 380-383 and line 411- What is the reference for the middle ear resonance at 1600Hz? How was it measured? I believe that other authors found that others that used the Titan found different resonance frequencies in the normal ear: https://www.advancedotology.org/content/files/sayilar/88/buyuk/157-1621.pdf
https://link.springer.com/article/10.1007/s00405-020-05909-9
It should have read significant increase in absorbance not resonant frequency and it is referring to Table 3 which is now fixed. You are absolutely right the Titan measures resonant frequency as well but was not reported or analyzed here. Furthermore, following your suggestion, we have eliminated "resonance frequency" throughout the article.
Lines 424-430 - I don't see any reason to use a self-citation of research conducted on animals. At the same time, there is a handful of research on SSCD in living humans, cadavers, and human temporal bone (Merchant, Rosowski, Roosli etc.)
Response: Thanks. Merchant. et al. (2015) findings were added. The contribution of quoting Attias' research, in this case, is that this research, for the first time, examined WBT after each and every step in the SSCD surgery.
Reviewer 2 Report
The authors studied the effect of severe to profound deafness and cochlear implant surgery in Wideband tympanometry
The study is interesting, it allows for evidence of the changes caused by hearing loss and cochlear implant surgery. It even allows identifying the frequency region of the WBT that is affected by each of the aspects mentioned above (Hearing loss and cochlear implant surgery)
The authors could assess whether the alterations found have any correlation with the performance with the CI
The conclusions agree with the investigation carried out and the results obtained. I think it would be better to create a separate section just to present the conclusions.
The figures and images are well organized and didactic for a better understanding of the text.
References are adequate and up-to-date.
On line 147, where 0.3-16 ml appears, 0.3-1.6 ml should appear
Author Response
We would also like to take this opportunity to thank the reviewer for his invaluable comments and inputs. Please find below our reply to each comment of the reviewer.
We hope that now the article is suitable for publication in the journal.
Authors
Reviewer 2
Comment: The authors could assess whether the alterations found have any correlation with the performance with the CI.
Excellent point. We have added this to the future direction (lines 513-514)
Comment: The conclusions agree with the investigation carried out and the results obtained. I think it would be better to create a separate section just to present the conclusions.
We believe the paragraph dedicated to the conclusion adequately addresses the reviewer's comment. (Lines 501-505).
On line 147, where 0.3-16 ml appears, 0.3-1.6 ml should appear
Fixed
Round 2
Reviewer 1 Report
The revised manuscript adequately addressed the issues that were raised. I believe that the article is now suitable for publication.
