scholarly journals Vibration direction sensitivity of the cochlea with bone conduction stimulation in guinea pigs

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mingduo Zhao ◽  
Anders Fridberger ◽  
Stefan Stenfelt
Keyword(s):  
Guinea Pig ◽  
Round Window ◽  
Bone Conduction ◽  
Three Dimensional ◽  
Hearing Threshold ◽  
Laser Doppler Vibrometer ◽  
Vibration Direction ◽  
Velocity Magnitude ◽  
Hearing Thresholds ◽  
Direction Sensitivity

AbstractSound and vibrations that cause the skull bone to vibrate can be heard as ordinary sounds and this is termed hearing by bone conduction (BC). Not all mechanisms that causes a skull vibration to result in BC hearing are known, and one such unknown is how the direction of the vibration influences BC hearing. This direction sensitivity was investigated by providing BC stimulation in five different directions at the vertex of the guinea pig skull. The hearing thresholds for BC stimulation was obtained in the frequency range of 2 to 20 kHz by measurements of compound action potential. During the stimulation by BC, the vibration of the cochlear promontory was measured with a three-dimensional laser Doppler vibrometer resulting in a set of unique three-dimensional velocity magnitude combinations for each threshold estimation. The sets of three-dimensional velocity magnitude at threshold were used to investigate nine different predictors of BC hearing based on cochlear promontory velocity magnitudes, six single direction (x, y and z directions in isolation, the normal to the stapes footplate, the oval to round window direction, and the cochlear base to apex direction), one linear combination of the three dimension velocity magnitudes, one square-rooted sum of the squared velocity magnitudes, and one sum of the weighted three dimensional velocity magnitudes based on a restricted minimum square error (MSE) estimation. The MSE gave the best predictions of the hearing threshold based on the cochlear promontory velocity magnitudes while using only a single direction gave the worst predictions of the hearing thresholds overall. According to the MSE estimation, at frequencies up to 8 kHz the vibration direction between the right and left side gave the greatest contribution to BC hearing in the guinea pig while at the highest frequencies measured, 16 and 20 kHz, the anteroposterior direction of the guinea pig head gave the greatest contribution.

scholarly journals Cutaneous and Labyrinthine Tolerance of Bioactive Glass S53P4 in Mastoid and Epitympanic Obliteration Surgery: Prospective Clinical Study

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Daniele Bernardeschi ◽  
Yann Nguyen ◽  
Francesca Yoshie Russo ◽  
Isabelle Mosnier ◽  
Evelyne Ferrary ◽  
...  
Keyword(s):  
Bioactive Glass ◽  
Inner Ear ◽  
Round Window ◽  
Bone Conduction ◽  
Hearing Threshold ◽  
Round Window Membrane ◽  
Prospective Clinical Study ◽  
Local Skin ◽  
Local Skin Reaction ◽  
Bone Conduction Hearing

Objective. To evaluate the cutaneous and the inner ear tolerance of bioactive glass S53P4 when used in the mastoid and epitympanic obliteration for chronic otitis surgery.Material and Methods. Forty-one cases have been included in this prospective study. Cutaneous tolerance was clinically evaluated 1 week, 1 month, and 3 months after surgery with a physical examination of the retroauricular and external auditory canal (EAC) skin and the presence of otalgia; the inner ear tolerance was assessed by bone-conduction hearing threshold 1 day after surgery and by the presence of vertigo or imbalance.Results. All surgeries but 1 were uneventful: all patients maintained the preoperative bone-conduction hearing threshold except for one case in which the round window membrane was opened during the dissection of the cholesteatoma in the hypotympanum and this led to a dead ear. No dizziness or vertigo was reported. Three months after surgery, healing was achieved in all cases with a healthy painless skin. No cases of revision surgery for removal of the granules occurred in this study.Conclusion. The bioactive glass S53P4 is a well-tolerated biomaterial for primary or revision chronic otitis surgery, as shown by the local skin reaction which lasted less than 3 months and by the absence of labyrinthine complications.

scholarly journals Examination of Insert Ear Interaural Attenuation (IA)Values in Audiological Evaluations

2016 ◽  
Vol 39 (6) ◽  
pp. 82
Author(s):  
Nebi M Gumus ◽  
Merve Gumus ◽  
Selim Unsal ◽  
Mustafa Yuksel ◽  
Mehmet Gunduz
Keyword(s):  
Healthy Subjects ◽  
Bone Conduction ◽  
Hearing Threshold ◽  
Hearing Thresholds ◽  
Bone Conduction Hearing ◽  
Insert Earphones ◽  
Otoscopic Examination

Purpose: The purpose of this study was to evaluate Interaural Attenuation (IA) in frequency base in the insert earphones that are used in audiological assessments. Methods: Thirty healthy subjects between 18-65 years of age (14 female and 16 male) participated in our study. Otoscopic examination was performed on all participants. Audiological evaluations were performed using the Interacoustics AC40 clinical audiometer and ER-3A insert earphones. IA value was calculated by subtracting good ear bone conduction hearing thresholds of the worst airway hearing threshold. Results: In our measuring for 0.125-8.0 kHz frequency were performed in our audiometry device separately for each frequency. IA amount in the results we found in 1000 Hz and below frequencies about 75-110 dB range avarage is 89±5dB, in above 1000 Hz frequencies in 50-95 dB range and avarage it is changed to 69±5dB. Conclusion: According to the obtained findings the quantity of melting in the transition between the ears are increasing with the insert earphones. The insert earphone should be beside supraaural earphone that is routinely used in clinics. Difficult masking applications due to the increase in the value of IA can be easily done with insert earphones.

Effects of lonomer Cement on Guinea Pig Cochleas

1997 ◽  
Vol 76 (4) ◽  
pp. 223-230 ◽  
Author(s):  
Taisuke Kobayashi ◽  
Yasuyuki Hinohira ◽  
Masamitsu Hyodo ◽  
Goran Bredberg ◽  
Edel Alsterborg
Keyword(s):  
Hearing Loss ◽  
Guinea Pig ◽  
Guinea Pigs ◽  
Morphological Study ◽  
Round Window ◽  
Cell Loss ◽  
Round Window Membrane ◽  
Hair Cell Loss ◽  
Ear Surgery ◽  
Hearing Thresholds

The inner ear toxicity of ionomeric cement (lonocem®) when used as a reconstructive material in ear surgery was evaluated in 47 guinea pigs used in a morphological study. The cement was implanted on either the promontory, the round window membrane or the stapes. There was no significant hair cell loss compared with the control ear at three weeks, two months or three months after implantation. Using electrocochleography, the hearing thresholds before, and three weeks, two and three months after the implantation were compared in an additional seven animals. No evident hearing loss was observed in any animal during the study period. No morphological or functional evidence for an ototoxic effect of the ionomeric cement was found in this study.

scholarly journals Case Report: Local Anesthesia Round Window Plugging and Simultaneous Vibrant Soundbridge Implant for Superior Semicircular Canal Dehiscence

2020 ◽  
Vol 11 ◽  
Author(s):  
Giulia Mignacco ◽  
Lorenzo Salerni ◽  
Ilaria Bindi ◽  
Giovanni Monciatti ◽  
Alfonso Cerase ◽  
...  
Keyword(s):  
Semicircular Canal ◽  
Round Window ◽  
Bone Conduction ◽  
Hearing Threshold ◽  
Vestibular Evoked Myogenic Potentials ◽  
Vibrant Soundbridge ◽  
Superior Semicircular Canal Dehiscence ◽  
Superior Semicircular Canal ◽  
The Right ◽  
Canal Dehiscence

The aim of the present study is to report the outcomes of round window reinforcement surgery performed with the application of a Vibrant Soundbridge middle ear implant (VSB; MED-EL) in a patient with superior semicircular canal dehiscence (SSCD) who presented with recurrent vertigo, Tullio phenomenon, Hennebert's sign, bone conduction hypersensitivity, and bilateral moderate to severe mixed hearing loss. Vestibular evoked myogenic potentials (VEMPs) and high-resolution computed tomography (HRCT) confirmed bilateral superior semicircular canal dehiscence while this was not seen in magnetic resonance imaging. The surgical procedure was performed in the right ear as it had worse vestibular and auditory symptoms, a poorer hearing threshold, and greatly altered HRCT and VEMPs findings. With local-assisted anesthesia, round window reinforcement surgery (plugging) with perichondrium was performed with simultaneous positioning of a VSB on the round window niche. At the one and 3 months follow-up after surgery, VSB-aided hearing threshold in the right ear improved to mild, and loud sounds did not elicit either dizziness or pain in the patient.

scholarly journals Hearing and hearing rehabilitation after obliteration of troublesome mastoid cavities

2020 ◽  
Vol 277 (12) ◽  
pp. 3307-3313
Author(s):  
Simon Geerse ◽  
Tim J. M. Bost ◽  
Samira Allagul ◽  
Maarten J. F. de Wolf ◽  
Fenna A. Ebbens ◽  
...  
Keyword(s):  
Hearing Aids ◽  
Revision Surgery ◽  
Residual Disease ◽  
Bone Conduction ◽  
Hearing Threshold ◽  
Patient Characteristics ◽  
Ossicular Chain ◽  
Mastoid Cavity ◽  
Hearing Thresholds ◽  
Ossicular Chain Reconstruction

Abstract Purpose The purpose of this study is the evaluation of post-operative hearing threshold after revision surgery and obliteration of troublesome canal wall down mastoidectomy cavities (CWDMCs). The ability to use and tolerate conventional hearing aids (CHAs) was also evaluated. Methods A retrospective chart analysis of 249 patients with chronically draining CWDMCs who underwent revision surgery including obliteration of the mastoid cavity between 2007 and 2017 at the AMC location of the Amsterdam University Medical Centers (Amsterdam UMC) was performed. Patient characteristics, pre- and post-operative Merchant grade, surgical outcomes, pre- and post-operative hearing thresholds, and the ability/necessity to use a CHA or the ability/necessity to use a Bone Conduction Device (BCD) were recorded. Results Dry ears were found in 95% of the total cohort. Residual disease was detected in 1.6% during MRI follow-up with no residual cholesteatoma in the obliterated area. In 3.2% of the patients, recurrent disease was found. A significant improvement in mean air conduction level, mean bone conduction level, and mean air-bone gap (ABG) was found post-operatively (p < 0.05). For all types of ossicular chain reconstruction, a significant improvement in mean Pure Tone Average was observed (p < 0.05). The percentage of patients with an indication for CHA was similar pre- and post-operatively (67% both pre- and post-operatively). The ability to use a CHA improved from 3% pre-operatively to 57% post-operatively (p < 0.001). Conclusion This study shows that revision surgery and obliteration of CWDMCs enable successful CHA rehabilitation post-operatively. Upon this type of surgery, hearing thresholds improve significantly, but the need for rehabilitation with a CHA remains necessary in most cases.

scholarly journals Objective Estimation of Frequency-Specific Pure-Tone Hearing Thresholds following Bone-Conduction Hearing Aid Stimulation

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Torsten Rahne ◽  
Thomas Ehelebe
Keyword(s):  
Pure Tone ◽  
Auditory Evoked Potentials ◽  
Bone Conduction ◽  
Hearing Threshold ◽  
Mixed Hearing Loss ◽  
Hearing Thresholds ◽  
Bone Conduction Hearing ◽  
Highly Correlated ◽  
Fitting In ◽  
Hearing System

Patients suffering from conductive or mixed hearing loss may benefit from bone-conduction hearing systems (BAHS). The amount of amplification provided by the hearing system is selected based on the individual’s sensorineural frequency-specific threshold. With patients who are not able to provide thresholds behaviorally, such as young children, objective methods are required to estimate the unaided and aided hearing threshold and thus the success of the hearing system fitting. In a prospective study with ten adult Baha softband users, aided and unaided frequency-specific thresholds were estimated. Aided thresholds to tone bursts via Baha stimulation were obtained behaviorally and electrophysiologically using cortical auditory evoked potentials (CAEPs) and were compared to pure-tone thresholds using routine clinical audiometry. For all stimulation frequencies, the frequency-specific electrophysiological and behavioral hearing thresholds measured with Baha stimulation were highly correlated and not different. Increased thresholds were observed only with the 0.5 kHz Baha stimulation as compared to the pure-tone audiogram. Objective measurement of frequency-specific hearing thresholds with CAEPs is applicable to BAHS users.

Sensorineural Hearing Loss After Radiotherapy and Chemoradiotherapy: A Single, Blinded, Randomized Study

2006 ◽  
Vol 24 (12) ◽  
pp. 1904-1909 ◽  
Author(s):  
Wong Kein Low ◽  
Song Tar Toh ◽  
Joseph Wee ◽  
Stephanie M.C. Fook-Chong ◽  
De Yun Wang
Keyword(s):  
Hearing Loss ◽  
Sensorineural Hearing Loss ◽  
Randomized Study ◽  
Bone Conduction ◽  
Hearing Threshold ◽  
Sensorineural Hearing ◽  
First Year ◽  
Radiotherapy Group ◽  
Hearing Thresholds ◽  
Radiotherapy Alone

Purpose The synergistic ototoxicity of radiation and cisplatin (CDDP) has not been adequately studied. This study investigated whether the use of concurrent and postradiotherapy CDDP in patients with nasopharyngeal carcinoma (NPC) resulted in a difference in postradiotherapy sensorineural hearing when compared with the use of radiotherapy alone. Patients and Methods Newly diagnosed patients were randomly assigned to the radiotherapy or chemoradiotherapy groups. Bone conduction hearing thresholds were performed before treatment and at 1 week, 6 months, 1 year, and 2 years after completion of radiotherapy. Statistical analysis was performed using the Mann-Whitney U test. Results Hearing thresholds averaged over 0.5, 1, and 2 kHz were found to be poorer in the chemoradiotherapy group (58 patients) compared with the radiotherapy group (57 patients) at 1 year (P = .001) and 2 years (P = .03) after radiotherapy. Hearing thresholds at 4 kHz were significantly worse for patients in the chemoradiotherapy arm at all of the postradiotherapy time points studied and were more severely affected than the thresholds at lower speech frequencies. In the radiotherapy group, deterioration of median hearing thresholds, which occurred in the immediate post-treatment period, improved within the first year but deteriorated again at 2 years. In the chemoradiotherapy group, median hearing threshold deterioration, which started immediately after radiotherapy, stabilized by 1 year. Conclusion Patients with NPC who received radiotherapy and concurrent/adjuvant chemotherapy using CDDP experienced greater sensorineural hearing loss compared with patients treated with radiotherapy alone, especially to high-frequency sounds in the speech range. Normal inner ear tissue tolerance, which was once defined only for radiotherapy patients alone, should be redefined in chemoradiotherapy patients.

scholarly journals Extended high-frequency audiometry in healthy adults with different age groups

2021 ◽  
Vol 50 (1) ◽  
Author(s):  
Mingming Wang ◽  
Yu Ai ◽  
Yuechen Han ◽  
Zhaomin Fan ◽  
Peng Shi ◽  
...  
Keyword(s):  
High Frequency ◽  
Pure Tone ◽  
Bone Conduction ◽  
Hearing Threshold ◽  
Healthy Population ◽  
Age Group ◽  
Hearing Ability ◽  
Hearing Thresholds ◽  
High Frequency Audiometry ◽  
Air Conduction

Abstract Background It was well-documented that extended high-frequency (EHF, above 8 kHz) hearing test could be more sensitive comparing with the conventional measurement on frequency below 8 kHz, regarding the early prediction of auditory damage in certain population. However, hardly any age-specific thresholds of EHF in population with normal hearing ability were observed. This study aims to monitor the age-dependent hearing thresholds at EHF (from 9 to 20 kHz) in healthy hearing population. Methods A total of 162 healthy participants (from 21 to 70 years) with normal conventional pure tone audiograms were recruited and separated into five groups by age. Conventional pure tone average was performed with frequencies from 0.25 to 8 kHz under air conduction and from 0.25 to 4 kHz under bone conduction. EHF audiometry from 9 to 20 kHz was determined under air conduction. Results The effects of aging on hearing were evident at frequencies above 4 kHz. The hearing thresholds of EHF were less than 26 dB HL before 30 years-olds. Hearing abilities in EHF were deteriorated starting from the 31 ~ 40 group and were most obvious in the 51 ~ 60 group and the 61 ~ 70 group with the maximum thresholds of 75 dB HL. Sensitivity of EHF was inversely proportional to the frequency within each age group, and to age among groups. Subjects under 30 years old were totally responsive up to 16 kHz, and 52.2% could respond to 20 kHz. Meanwhile, no responsiveness was recorded to 20 kHz in the 51 ~ 60 group and even to 18 kHz in the 61 ~ 70 group. No gender differences in hearing threshold was observed within each age group, except an obvious decline at frequencies of 4, 6, 8, and 9 kHz in male participants of the 41 ~ 50 group. Conclusions Hearing thresholds at EHF from 9 to 20 kHz were more sensitive than at frequencies below 8 kHz for hearing measurement, and aging inversely affected hearing ability at EHF in healthy population. Hearing thresholds at EHF deteriorated with age and raising frequency, while the upper frequency limit decreased with aging. Graphical abstract

scholarly journals Early hearing threshold changes and peculiarities of audiometric assessments among patients in a drug-resistant tuberculosis treatment center

2021 ◽  
Vol 21 (1) ◽  
pp. 230-7
Author(s):  
Olusola A Sogebi ◽  
Bolanle O Adefuye ◽  
Ebenezer A Ajayi
Keyword(s):  
Bone Conduction ◽  
Hearing Threshold ◽  
Tuberculosis Treatment ◽  
Treatment Center ◽  
Drug Resistant ◽  
Drug Resistant Tuberculosis ◽  
Resistant Tuberculosis ◽  
Hearing Thresholds ◽  
Bone Conduction Hearing ◽  
Pre Treatment

Background: Hearing threshold changes occurred relative to baseline at both one and two weeks after onset of aminogly- coside therapy. Objectives: To assess changes in audiometric hearing thresholds between pre-treatment values and two weeks into therapy. To document observed changes, and occurrence of ototoxicity within the period. Methods: Prospective analytical cohort study on drug-resistant tuberculosis patients. Basic demographic parameters were taken. Three-point audiometric assessments within two weeks into therapy were done. Percentage of patients with ototoxic- ity were calculated. Pure tone threshold changes between the three audiometric values were compared. Results: Audiograms of 53 patients comprising 56.6% males; age range was 13 to 91 years. Both air and bone conduction hearing thresholds significantly worsened between baseline and one week into therapy (p=0.011, and 0.015 respectively), and between baseline and two weeks into therapy (p=0.003 and 0.042 respectively). Minimal insignificant reduction occurred between both air and bone conduction hearing values of week 1 and week 2 of therapy (p= 1.000 and 0.856 respectively). By audiometric criteria, 4 patients (7.5%) developed ototoxicity within two weeks of treatment. Conclusion: Audiometric assessments within two weeks into therapy with anti-tuberculous therapy may not represent baseline audiometry. 7.5% of the patients developed ototoxicity within two weeks of therapy. Keywords: Early hearing threshold changes; audiometric assessments; tuberculosis treatment center.

Effect of Contraceptive Steroids on the Endometrium of Guinea Pig: SEM study

1977 ◽  
Vol 35 ◽  
pp. 668-669
Author(s):  
Mai M. Said ◽  
Ramesh K. Nayak ◽  
Randall E. McCoy
Keyword(s):  
Guinea Pig ◽  
Reproductive Tract ◽  
Three Dimensional ◽  
Female Reproductive Tract ◽  
Human Female ◽  
Surface Ultrastructure ◽  
Transmission Electron ◽  
Sem Study ◽  
Uterine Mucosa ◽  
Group 1

Burgos and Wislocki described changes in the mucosa of the guinea pig uterus, cervix and vagina during the estrous cycle investigated by transmission electron microscopy. More recently, Moghissi and Reame reported the effects of progestational agents on the human female reproductive tract. They found drooping and shortening of cilia in norgestrel and norethindrone- treated endometria. To the best of our knowledge, no studies concerning the effects of mestranol and norethindrone given concurrently on the three-dimensional surface features on the uterine mucosa of the guinea pig have been reported. The purpose of this study was to determine the effect of mestranol and norethindrone on surface ultrastructure of guinea pig uterus by SEM.Seventy eight animals were used in this study. They were allocated into two groups. Group 1 (20 animals) was injected intramuscularly 0.1 ml vegetable oil and served as controls.

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