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Sample records for ear cochlear function

  1. Middle-ear velocity transfer function, cochlear input immittance, and middle-ear efficiency in chinchilla

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    Ravicz, Michael E.; Rosowski, John J.

    2013-01-01

    The transfer function HV between stapes velocity VS and sound pressure near the tympanic membrane PTM is a descriptor of sound transmission through the middle ear (ME). The ME power transmission efficiency (MEE), the ratio of sound power entering the cochlea to power entering the middle ear, was computed from HV measured in seven chinchilla ears and previously reported measurements of ME input admittance YTM and ME pressure gain GMEP [Ravicz and Rosowski, J. Acoust. Soc. Am. 132, 2437–2454 (2012); J. Acoust. Soc. Am. 133, 2208–2223 (2013)] in the same ears. The ME was open, and a pressure sensor was inserted into the cochlear vestibule for most measurements. The cochlear input admittance YC computed from HV and GMEP is controlled by a combination of mass and resistance and is consistent with a minimum-phase system up to 27 kHz. The real part Re{YC}, which relates cochlear sound power to inner-ear sound pressure, decreased gradually with frequency up to 25 kHz and more rapidly above that. MEE was about 0.5 between 0.1 and 8 kHz, higher than previous estimates in this species, and decreased sharply at higher frequencies. PMID:24116422

  2. The Impact of a Cochlear Implant Electrode Array on the Middle Ear Transfer Function.

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    Pazen, David; Anagiotos, Andreas; Nünning, Maike; Gostian, Antoniu-Oreste; Ortmann, Magdalene; Beutner, Dirk

    As a treatment for partial deafness with residual hearing in the lower frequency range, the combined acoustic and electric stimulation of the cochlea has become widespread. Acoustic stimulation is provided by a hearing aid's airborne sound and the electric stimulation by a cochlear implant electrode array, which may be inserted through the round window or a cochleostomy. To take advantage of that concept, it is essential to preserve residual hearing after surgery. Therefore, the intracochlear electrode array should not compromise the middle ear vibration transmission. This study investigates the influence of different electrode types and insertion paths on the middle ear transfer function and the inner ear fluid dynamics. Sound-induced oval and round window net volume velocities were calculated from vibration measurements with laser vibrometers on six nonfixated human temporal bones. After baseline measurements in the "natural" condition, a cochleostomy was drilled and closed with connective tissue. Then, four different electrode arrays were inserted through the cochleostomy. Afterwards, they were inserted through the round window while the cochleostomy was patched again with connective tissue. After having drilled a cochleostomy and electrode insertion, no systematic trends in the changes of oval and round window volume velocities were observed. Nearly all changes of middle ear transfer functions, as well as oval and round window volume velocity ratios, were statistically insignificant. Intracochlear electrode arrays do not significantly increase cochlear input impedance immediately after insertion. Any changes that may occur seem to be independent of electrode array type and insertion path.

  3. Ear asymmetries in middle-ear, cochlear, and brainstem responses in human infants.

    Science.gov (United States)

    Keefe, Douglas H; Gorga, Michael P; Jesteadt, Walt; Smith, Lynette M

    2008-03-01

    In 2004, Sininger and Cone-Wesson examined asymmetries in the signal-to-noise ratio (SNR) of otoacoustic emissions (OAE) in infants, reporting that distortion-product (DP)OAE SNR was larger in the left ear, whereas transient-evoked (TE)OAE SNR was larger in the right. They proposed that cochlear and brainstem asymmetries facilitate development of brain-hemispheric specialization for sound processing. Similarly, in 2006 Sininger and Cone-Wesson described ear asymmetries mainly favoring the right ear in infant auditory brainstem responses (ABRs). The present study analyzed 2640 infant responses to further explore these effects. Ear differences in OAE SNR, signal, and noise were evaluated separately and across frequencies (1.5, 2, 3, and 4 kHz), and ABR asymmetries were compared with cochlear asymmetries. Analyses of ear-canal reflectance and admittance showed that asymmetries in middle-ear functioning did not explain cochlear and brainstem asymmetries. Current results are consistent with earlier studies showing right-ear dominance for TEOAE and ABR. Noise levels were higher in the right ear for OAEs and ABRs, causing ear asymmetries in SNR to differ from those in signal level. No left-ear dominance for DPOAE signal was observed. These results do not support a theory that ear asymmetries in cochlear processing mimic hemispheric brain specialization for auditory processing.

  4. Predictions of middle-ear and passive cochlear mechanics using a finite element model of the pediatric ear

    OpenAIRE

    Wang, Xuelin; Keefe, Douglas H.; Gan, Rong Z.

    2016-01-01

    A finite element (FE) model was developed based on histological sections of a temporal bone of a 4-year-old child to simulate middle-ear and cochlear function in ears with normal hearing and otitis media. This pediatric model of the normal ear, consisting of an ear canal, middle ear, and spiral cochlea, was first validated with published energy absorbance (EA) measurements in young children with normal ears. The model was used to simulate EA in an ear with middle-ear effusion, whose results w...

  5. Predictions of middle-ear and passive cochlear mechanics using a finite element model of the pediatric ear.

    Science.gov (United States)

    Wang, Xuelin; Keefe, Douglas H; Gan, Rong Z

    2016-04-01

    A finite element (FE) model was developed based on histological sections of a temporal bone of a 4-year-old child to simulate middle-ear and cochlear function in ears with normal hearing and otitis media. This pediatric model of the normal ear, consisting of an ear canal, middle ear, and spiral cochlea, was first validated with published energy absorbance (EA) measurements in young children with normal ears. The model was used to simulate EA in an ear with middle-ear effusion, whose results were compared to clinical EA measurements. The spiral cochlea component of the model was constructed under the assumption that the mechanics were passive. The FE model predicted middle-ear transfer functions between the ear canal and cochlea. Effects of ear structure and mechanical properties of soft tissues were compared in model predictions for the pediatric and adult ears. EA responses are predicted to differ between adult and pediatric ears due to differences in the stiffness and damping of soft tissues within the ear, and any residual geometrical differences between the adult ear and pediatric ear at age 4 years. The results have significance for predicting effects of otitis media in children.

  6. Rhesus Cochlear and Vestibular Functions Are Preserved After Inner Ear Injection of Saline Volume Sufficient for Gene Therapy Delivery.

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    Dai, Chenkai; Lehar, Mohamed; Sun, Daniel Q; Rvt, Lani Swarthout; Carey, John P; MacLachlan, Tim; Brough, Doug; Staecker, Hinrich; Della Santina, Alexandra M; Hullar, Timothy E; Della Santina, Charles C

    2017-08-01

    Sensorineural losses of hearing and vestibular sensation due to hair cell dysfunction are among the most common disabilities. Recent preclinical research demonstrates that treatment of the inner ear with a variety of compounds, including gene therapy agents, may elicit regeneration and/or repair of hair cells in animals exposed to ototoxic medications or other insults to the inner ear. Delivery of gene therapy may also offer a means for treatment of hereditary hearing loss. However, injection of a fluid volume sufficient to deliver an adequate dose of a pharmacologic agent could, in theory, cause inner ear trauma that compromises functional outcome. The primary goal of the present study was to assess that risk in rhesus monkeys, which closely approximates humans with regard to middle and inner ear anatomy. Secondary goals were to identify the best delivery route into the primate ear from among two common surgical approaches (i.e., via an oval window stapedotomy and via the round window) and to determine the relative volumes of rhesus, rodent, and human labyrinths for extrapolation of results to other species. We measured hearing and vestibular functions before and 2, 4, and 8 weeks after unilateral injection of phosphate-buffered saline vehicle (PBSV) into the perilymphatic space of normal rhesus monkeys at volumes sufficient to deliver an atoh1 gene therapy vector. To isolate effects of injection, PBSV without vector was used. Assays included behavioral observation, auditory brainstem responses, distortion product otoacoustic emissions, and scleral coil measurement of vestibulo-ocular reflexes during whole-body rotation in darkness. Three groups (N = 3 each) were studied. Group A received a 10 μL transmastoid/trans-stapes injection via a laser stapedotomy. Group B received a 10 μL transmastoid/trans-round window injection. Group C received a 30 μL transmastoid/trans-round window injection. We also measured inner ear fluid space volume via 3D

  7. Cochlear implantation in the Mondini inner ear malformation.

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    Miyamoto, R T; Robbins, A J; Myres, W A; Pope, M L

    1986-07-01

    We report the case of a profoundly deaf 4-year-old boy with congenital deafness as a result of Mondini's dysplasia. The Mondini inner ear malformation is the result of arrested labyrinthine development during embryogenesis and is characterized by both bony and membranous anomalies of the inner ear. The dysplastic cochlear anatomy does not preclude successful cochlear implantation, and electrical threshold measurements are similar to those recorded in pediatric subjects deafened as a result of other causes.

  8. Prevalence of inner ear anomalies among cochlear implant candidates.

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    Aldhafeeri, Ahmad M; Alsanosi, Abdulrahman A

    2016-10-01

    To determine the prevalence of inner ear anomalies and the frequency of different anomaly types among cochlear implant recipients. This study included a retrospective chart review of all patients who received cochlear implants between January 2009 and January 2013 in King Abdulaziz University Hospital cochlear implant program in Riyadh, Saudi Arabia. All subjects underwent thin-cut CT of the temporal bone and MRI. The collected data included age, gender, and CT and MRI findings regarding temporal bone anomalies. Patients with any identified congenital inner ear anomalies were included in the study.  In total, 316 patients' cases were reviewed. Inner ear malformations were identified in 24 patients, which represented a prevalence of 7.5%. Among these 24 patients, 8 (33.3%) presented with a large vestibular aqueduct (LVA), 8 (33.3%) semicircular canal (SCC) dysplasia, 7 (29.1%) classical Mondini deformity, and one (4.1%) cochlear hypoplasia. The prevalence of inner ear anomalies among cochlear implant recipients was 7.5%. This result is consistent with findings worldwide. The most common anomalies were LVA and SCC hypoplasia; by contrast, in other regions, the most common anomaly is either the Mondini deformity, or LVA.

  9. [Cochlear implant in patients with congenital malformation of the inner ear].

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    Wan, Liang-cai; Guo, Meng-he; Qian, Yu-hong; Liu, Shuang-xiu; Zhang, Hong-zheng; Chen, Shuai-jun; Chen, Hao; Gong, Jian

    2009-10-01

    To summarize the clinical experience with multi-channel cochlear implantation in patients with inner ear malformations and evaluate and the outcomes of speech rehabilitation. A retrospective study was conducted in 295 patients receiving cochlear implantation from 1998 to 2007, including 25 patients with large vestibular aqueduct syndrome (LVAS), 9 with Modini malformation, and 5 with common cavity deformity. All the patients received the Nucleus24 cochlear implants. In LVAS cases, 4 had Nucleus 24R (ST) implants, 8 had Contuor implants, 10 had Contuor Advance, and the remaining cases used Nucleus24(M) straight-electrode implants. Severe gusher appeared in 3 cases of LVAS, and perilymph fluctuation were seen in other 15 cases. Four patients with Mondini malformation and 2 with common cavity malformation also experienced severe gusher, but the electrodes were inserted smoothly in all the patients without postoperative facial paralysis or cerebrospinal fluid leakage. The hearing threshold in these patients was similar to that in patients with normal cochlear structure. After speech rehabilitation for over 6 months, the abilities of speech discrimination and spoken language improved in all the cases in comparison with the preoperative lingual functions. Multi-channel cochlear implantation can be performed in patients with inner ear malformation, but should not be attempted in patients with poor cochlear and cochlear nerve development. A comprehensive pre-operative radiographic and audiological evaluation is essential.

  10. [Cochlear implant in patients with congenital malformation of inner ear].

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    Han, Dong-yi; Wu, Wen-ming; Xi, Xin; Huang, De-liang; Yang, Wei-yan

    2004-02-01

    To study surgical difficulty and key of the cochlear implant in patients with congenital malformation of inner ear. The cochlear implantations were performed in our department from Jan. 2001 to Apr. 2003 for 18 patients with the malformation of inner ear. In this series, there were 11 cases of large vestibular aqueduct syndrome (LVAS), 3 cases of Waardenberg syndrome, 3 cases of Mondini malformation, and 1 case of Usher syndrome. All 18 patients accepted the Nucleus 24-channel cochlear implantations, including Nucleus straight electrode in 13 cases but Contour implantation in 5 cases of LVAS. During operations, leakage of perilymph but not cerebrospinal fluid (CSF) from the open of scala tympani occurred in 11 cases of LVAS, however, the electrode was inserted successfully. The abnormalities of round window occurred in one of 3 cases of Waardenberg syndrome and 3 cases of Mondini malformation, respectively. The cochlear implant could be conducted successfully for the LVAS, and the postoperative effect was same as the ones for the deafness persons with normal development of inner ear. However, for the patients with Mondini syndrome and common cavity, it is important to accurately assess the extent of abnormalities in the inner ear and accompanied malformation before operation, and to evaluate the full extent of difficulties of the operation in order to minimize the risk of CSF leakage and meningitis.

  11. Effects of NSAIDs on the Inner Ear: Possible Involvement in Cochlear Protection

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    Akira Hara

    2010-04-01

    Full Text Available Cyclooxygenase and lipoxygenase, two important enzymes involved in arachidonic acid metabolism, are major targets of non-steroidal anti-inflammatory drugs (NSAIDs. Recent investigations suggest that arachidonic cascades and their metabolites may be involved in maintaining inner ear functions. The excessive use of aspirin may cause tinnitus in humans and impairment of the outer hair cell functions in experimental animals. On the other hand, NSAIDs reportedly exhibit protective effects against various kinds of inner ear disorder. The present review summarizes the effects of NSAIDs on cochlear pathophysiology. NSAIDs are a useful ameliorative adjunct in the management of inner ear disorders.

  12. Air-bone gap component of inner-ear origin in audiograms of cochlear implant candidates.

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    Attias, Joseph; Ulanovski, David; Shemesh, Rafael; Kornreich, Liora; Nageris, Benny; Preis, Michal; Peled, Miriam; Efrati, Michal; Raveh, Eyal

    2012-06-01

    Experimental studies have shown that creating a window in the bony cover of the cochlea and vestibular parts of the inner ear, with preservation of membranous and middle-ear functions, induces an air-bone gap (ABG). This study sought to determine if a similar mechanism explains the ABG frequently observed in audiograms of cochlear implant candidates. The study group included 47 candidates for a cochlear implant (94 ears) attending a university-affiliated tertiary medical center who had an ABG component in the audiogram in the absence of external or middle-ear abnormalities. Air- and bone-conduction thresholds on pure-tone audiometry were analyzed for 250 to 8,000 Hz and 250 to 4,000 Hz, respectively. In the 25 patients operated on during the study period, differences in the ABG and in cerebrospinal fluid (CSF) leak were compared between those with and without anomalies on computed tomography. Imaging revealed an abnormal inner-ear structure in 46% of cases, mostly a large vestibular aqueduct, alone or combined with other cochlear or vestibular malformations. ABG was evident over high and low frequencies and was significantly larger at low frequencies and in ears with structural anomalies. A high rate of CSF leak was observed in patients with an ABG and structural anomalies imaging as well as in those with an ABG and normal imaging findings. In cochlear implant candidates, the presence of a third window could cause an ABG because of stapes motion-induced shunting of acoustic energy outside the cochlear duct in response to air-conducted stimuli while bone conduction is preserved.

  13. Ear asymmetries in middle-ear, cochlear, and brainstem responses in human infants

    OpenAIRE

    Keefe, Douglas H.; Gorga, Michael P.; Jesteadt, Walt; Smith, Lynette M.

    2008-01-01

    In 2004, Sininger and Cone-Wesson examined asymmetries in the signal-to-noise ratio (SNR) of otoacoustic emissions (OAE) in infants, reporting that distortion-product (DP)OAE SNR was larger in the left ear, whereas transient-evoked (TE)OAE SNR was larger in the right. They proposed that cochlear and brainstem asymmetries facilitate development of brain-hemispheric specialization for sound processing. Similarly, in 2006 Sininger and Cone-Wesson described ear asymmetries mainly favoring the rig...

  14. "COCHLEAR IMPLANTATION IN PATIENTS WITH INNER EAR MALFORMATIONS"

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    P. Borghei S. Abdi

    2004-08-01

    Full Text Available Performing cochlear implantation in patients with inner ear malformation has always been a matter of dispute. This study was designed to analyze the operative findings,complications, and postoperative performance of patients with inner ear anomalies who underwent cochlear implantation. Six patients with inner ear malformations underwent implantation in our academic tertiary referral center from 1997 to 2002. The average follow-up period was 27 months. Malformations included one incomplete partition, one common cavity, one narrow internal acoustic canal (IAC in a patient with Riley-Day syndrome and 3 cases of large vestibular aqueduct. All received multi-channel implants either Nucleus 22 or Clarion device. Facial nerve was anomalous in 2 cases. CSF gusher occurred in 4 patients, which was controlled with packing the cochleostomy site. In all cases, the full length of electrode array was inserted, except one with Mondini's dysplasia where insertion failed in the first operation and was referred to another center for a successful surgery on the opposite ear. No other surgical complications were encountered. In 4 cases, all the 22 electrodes could be activated. All patients showed improved hearing performance after implantation. Four showed open-set speech recognition. The one with narrow IAC showed improved awareness to environmental sounds. In the other case (common cavity, the perception tests could not be performed because of very young age. Cochlear implantation in patients with inner ear malformations is a successful way of rehabilitation, although complications should be expected and auditory responses may be highly variable and relatively moderate.

  15. Cochlear Implant Stimulation of a Hearing Ear Generates Separate Electrophonic and Electroneural Responses.

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    Sato, Mika; Baumhoff, Peter; Kral, Andrej

    2016-01-06

    Electroacoustic stimulation in subjects with residual hearing is becoming more widely used in clinical practice. However, little is known about the properties of electrically induced responses in the hearing cochlea. In the present study, normal-hearing guinea pig cochleae underwent cochlear implantation through a cochleostomy without significant loss of hearing. Using recordings of unit activity in the midbrain, we were able to investigate the excitation patterns throughout the tonotopic field determined by acoustic stimulation. With the cochlear implant and the midbrain multielectrode arrays left in place, the ears were pharmacologically deafened and electrical stimulation was repeated in the deafened condition. The results demonstrate that, in addition to direct neuronal (electroneuronal) stimulation, in the hearing cochlea excitation of the hair cells occurs ("electrophonic responses") at the cochlear site corresponding to the dominant temporal frequency components of the electrical stimulus, provided these are cochlear implants and hearing aids is becoming more widely clinically used in subjects with residual hearing. The neurophysiological characteristics underlying electroacoustic stimulation and the mechanism of its benefit remain unclear. The present study directly demonstrates that cochlear implantation does not interfere with the normal mechanical and physiological function of the cochlea. For the first time, it double-dissociates the electrical responses of hair cells (electrophonic responses) from responses of the auditory nerve fibers (electroneural responses), with separate excited cochlear locations in the same animals. We describe the condition in which these two responses spatially overlap. Finally, the study implicates that using the clinical characteristics of stimulation makes electrophonic responses unlikely in implanted subjects. Copyright © 2016 the authors 0270-6474/16/360054-11$15.00/0.

  16. The middle ear muscle reflex in the diagnosis of cochlear neuropathy.

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    Valero, Michelle D; Hancock, Kenneth E; Liberman, M Charles

    2016-02-01

    Cochlear neuropathy, i.e. the loss of auditory nerve fibers (ANFs) without loss of hair cells, may cause hearing deficits without affecting threshold sensitivity, particularly if the subset of ANFs with high thresholds and low spontaneous rates (SRs) is preferentially lost, as appears to be the case in both aging and noise-damaged cochleas. Because low-SR fibers may also be important drivers of the medial olivocochlear reflex (MOCR) and middle-ear muscle reflex (MEMR), these reflexes might be sensitive metrics of cochlear neuropathy. To test this hypothesis, we measured reflex strength and reflex threshold in mice with noise-induced neuropathy, as documented by confocal analysis of immunostained cochlear whole-mounts. To assay the MOCR, we measured contra-noise modulation of ipsilateral distortion-product otoacoustic emissions (DPOAEs) before and after the administration of curare to block the MEMR or curare + strychnine to also block the MOCR. The modulation of DPOAEs was 1) dominated by the MEMR in anesthetized mice, with a smaller contribution from the MOCR, and 2) significantly attenuated in neuropathic mice, but only when the MEMR was intact. We then measured MEMR growth functions by monitoring contra-noise induced changes in the wideband reflectance of chirps presented to the ipsilateral ear. We found 1) that the changes in wideband reflectance were mediated by the MEMR alone, and 2) that MEMR threshold was elevated and its maximum amplitude was attenuated in neuropathic mice. These data suggest that the MEMR may be valuable in the early detection of cochlear neuropathy. Published by Elsevier B.V.

  17. Determining compliance of ear CT scan with interaoperative findings in deaf children with cochlear implantation.

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    Mohammad, Ajalloueyan; Mohammad Bagher, Sadeghi; Mahdi, Mirmohammad; Zahra, Ajalloueyan

    2015-08-01

    Defecated or impaired hair cell function of the cochlea causes deafness. Cochlear implantation allows transmission of sound information through central auditory pathways using direct electric stimulation of auditory nerve dendrites. Using radiologic imaging, including CT scan is very helpful in selection of candidates and evaluation after implantation. The purpose of this study is to determine compliance of CT findings in deaf children undergoing cochlear implantation compared with the intra-operative findings. In a periodical-descriptive study, 100 patients (56 male and 44 female), 6 months to 6 years of age, who were candidates for cochlear implantation at Baqiyatallah Hospital in Tehran between January 2010 and October 2011, were studied. After getting informed consent form the parents of patients, demographic data was recorded. CT scan and surgical data were double blindly collected in the designed questionnaire which was approved by three radiologists and three ENT specialists. Finally, surgical and radiological data were compared and t-test and chi-square test was used. Atic status in 89 patients (89%) was statistically significant between radiology and surgery (P=0.06). Positive Predictive Value and Negative Predictive Value were respectively 100 and 92.8. Middle ear space was same in 85 patients (85%) in the two methods (P=0.01) (NVP=63.4). Pyramid status was similar in radiology and surgery results in 67 patients (67%) (P=0.000) and PPV and NPV were 100 and 63.4 respectively. Jugular bulb was similar in 73 patients (73%) (P=0.00). There was no significant difference between other modalities. In most cases examined in this study, compliance between the surgical and radiological findings was above 80%. In some cases, CT scan could give confidence to the surgeon, but in atic, middle ear space, pyramid and jugular bulb there might be insufficient reliance to CT findings and there would be need to more accurate observation during surgery. Copyright © 2015

  18. Cochlear aqueduct flow resistance is not constant during evoked inner ear pressure change in the guinea pig

    NARCIS (Netherlands)

    Wit, HP; Feijen, RA; Albers, FWJ

    Inner ear fluid pressure was measured during 6.25 mHz square wave middle ear pressure manipulation, with a perforated tympanic membrane. After a negative-going middle ear pressure change the calculated flow resistance of the inner ear pressure release routes (mainly the cochlear aqueduct) was

  19. [Meta-analysis of the efficacy of cochlear implantation in deaf patients with inner ear malformation].

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    Xu, Qingqing; Zhai, Suoqiang; Han, Dongyi; Yang, Shiming; Shen, Weidong

    2014-04-01

    Assess and compare the clinical efficacy and safety of cochlear implantation in deaf patients with inner ear malformation and in the ones with normal inner ear structure, so that to clarify whether it is effective to restore hearing for the deaf patients with inner ear malformation. The literature with relevant key words were retrieved in the databases including PubMed, YZ365. com, WANFANG data, CMJD, CHKD and CNKI with language limited to Chinese and English. Extracted data included author, year of publication, diagnosis, treatment, et al. The clinical efficacy of cochlear implantation was assessed by the complications, electrode impedance, behavior T-level, hearing abilities and speech discrimination. Meta-analysis was performed using random or fixed effects model according to the heterogeneity of data. There were 11 randomized control studies involving 655 patients included in this study. There was no statistically significant difference among the deaf patients in mixed inner ear-malformation group, Mondini group and large vestibular aqueduct syndrome group in the aspects of postoperative complications, electrode impedance, behavior T-level, hearing abilities and speech discrimination. Cochlear implantation could be the way of treatment and rehabilitation for deaf patients with inner ear malformation. Further controlled studies with longer follow-up periods and more multiracial cases included may help to evaluate the efficacy of cochlear implantation for deaf patients with inner ear malformation more reliably.

  20. [Effect of rehabilitation for prelingual deaf children who use cochlear implants in conjunction with hearing aids in the opposite ears].

    Science.gov (United States)

    Tian, Yanjing; Zhou, Huifang; Zhang, Jing; Yang, Dong; Xu, Yi; Guo, Yuxi

    2012-10-01

    To compare the effect of rehabilitation of prelingual deaf children who used a cochlear implant (CI) in one ear and a hearing aids in the opposite ear while the hearing level of the opposite ears are different. Hearing ability, language ability and learning ability was included in the content. The aim of this research is to investigate better style of rehabilitation, and to offer the best help to the prelingual deaf children. Accord ing to the hearing level of the ear opposite to the one wearing a cochlear implant and whether the opposite ear wear a hearing aid or not, 30 prelingual deaf children were divided into three groups, including cochlear implant with opposite severe hearing loss and hearing aid ear (CI+SHA), cochlear implant with opposite profound hearing loss and hearing aid ear (CI+PHA), cochlear implant only (CI). The effect of rehabilitation was assessed in six different times (3,6,9,12,15 and 18 months after the cochlear implants and hearing aids began to work). The longer time the rehabilitation spends, the better the hearing ability,language ability and the learning ability were. The hearing ability of CI+SHA was better than those of CI+PHA (Pdeaf children should take much more time on rehabilitation. The effect of rehabilitation for prelingual deaf children who used cochlear implant in one ear and hearing aid in the other depend on the residual hearing level of the other ear. If a prelingual deaf children still has any residual hearing level in the ear opposite to the cochlear implant ear, it is better for him/her to wear a hearing aid in the ear.

  1. Influence of cochlear implantation on peripheral vestibular receptor function.

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    Krause, Eike; Louza, Julia P R; Wechtenbruch, Juliane; Gürkov, Robert

    2010-06-01

    The objectives of this study were 1) to assess the influence of a cochlear implantation on peripheral vestibular receptor function in the inner ear in the implant and in the nonimplant side, and 2) to analyze a possible correlation with resulting vertigo symptoms. Prospective clinical study. Cochlear implant center at tertiary referral hospital. A total of 32 patients, aged 15 to 83 years, undergoing cochlear implantation were assessed pre- and postoperatively for caloric horizontal semicircular canal response and vestibular-evoked myogenic potentials of the sacculus, and postoperatively for subjective vertigo symptoms. Patients with vertigo were compared with patients without symptoms with regard to the findings of the vestibular function tests. Cochlear implantation represents a significant risk factor for horizontal semicircular canal impairment (P 0.05). Cochlear implantation is a relevant risk factor for damage of peripheral vestibular receptor function. Therefore, preservation not only of residual hearing function but also of vestibular function should be aimed for, by using minimally invasive surgical techniques. Copyright 2010 American Academy of Otolaryngology-Head and Neck Surgery Foundation. Published by Mosby, Inc. All rights reserved.

  2. Cochlear Implantation in Patients with Neurofibromatosis Type 2 and Patients with Vestibular Schwannoma in the Only Hearing Ear

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    Erika Celis-Aguilar

    2012-01-01

    Full Text Available Cochlear implants are a new surgical option in the hearing rehabilitation of patients with neurofibromatosis type 2 (NF2 and patients with vestibular schwannoma (VS in the only hearing ear. Auditory brainstem implant (ABI has been the standard surgical treatment for these patients. We performed a literature review of patients with NF2 and patients with VS in the only hearing ear. Cochlear implantation (CI provided some auditory benefit in all patients. Preservation of cochlear nerve integrity is crucial after VS resection. Results ranged from environmental sound awareness to excellent benefit with telephone use. Promontory stimulation is recommended although not crucial. MRI can be performed safely in cochlear implanted patients.

  3. Cochlear Implant Outcomes and Genetic Mutations in Children with Ear and Brain Anomalies

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    Micol Busi

    2015-01-01

    Full Text Available Background. Specific clinical conditions could compromise cochlear implantation outcomes and drastically reduce the chance of an acceptable development of perceptual and linguistic capabilities. These conditions should certainly include the presence of inner ear malformations or brain abnormalities. The aims of this work were to study the diagnostic value of high resolution computed tomography (HRCT and magnetic resonance imaging (MRI in children with sensorineural hearing loss who were candidates for cochlear implants and to analyse the anatomic abnormalities of the ear and brain in patients who underwent cochlear implantation. We also analysed the effects of ear malformations and brain anomalies on the CI outcomes, speculating on their potential role in the management of language developmental disorders. Methods. The present study is a retrospective observational review of cochlear implant outcomes among hearing-impaired children who presented ear and/or brain anomalies at neuroimaging investigations with MRI and HRCT. Furthermore, genetic results from molecular genetic investigations (GJB2/GJB6 and, additionally, in selected cases, SLC26A4 or mitochondrial-DNA mutations on this study group were herein described. Longitudinal and cross-sectional analysis was conducted using statistical tests. Results. Between January 1, 1996 and April 1, 2012, at the ENT-Audiology Department of the University Hospital of Ferrara, 620 cochlear implantations were performed. There were 426 implanted children at the time of the present study (who were <18 years. Among these, 143 patients (64 females and 79 males presented ear and/or brain anomalies/lesions/malformations at neuroimaging investigations with MRI and HRCT. The age of the main study group (143 implanted children ranged from 9 months and 16 years (average = 4.4; median = 3.0. Conclusions. Good outcomes with cochlear implants are possible in patients who present with inner ear or brain abnormalities

  4. Form and function of the mammalian inner ear.

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    Ekdale, Eric G

    2016-02-01

    The inner ear of mammals consists of the cochlea, which is involved with the sense of hearing, and the vestibule and three semicircular canals, which are involved with the sense of balance. Although different regions of the inner ear contribute to different functions, the bony chambers and membranous ducts are morphologically continuous. The gross anatomy of the cochlea that has been related to auditory physiologies includes overall size of the structure, including volume and total spiral length, development of internal cochlear structures, including the primary and secondary bony laminae, morphology of the spiral nerve ganglion, and the nature of cochlear coiling, including total number of turns completed by the cochlear canal and the relative diameters of the basal and apical turns. The overall sizes, shapes, and orientations of the semicircular canals are related to sensitivity to head rotations and possibly locomotor behaviors. Intraspecific variation, primarily in the shape and orientation of the semicircular canals, may provide additional clues to help us better understand form and function of the inner ear. © 2015 Anatomical Society.

  5. Postoperative objective detecting techniques for cochlear implant children with inner ear malformation.

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    Qiao, Xiao-Feng; Li, Xin; Zhang, Qiang-Wei; Li, Tong-Li; Wang, Dong

    2017-11-01

    This study aims to investigate the changing characteristics and rules of electrically-evoked auditory brainstem response (EABR), electrically-evoked stapedius reflex threshold (ESRT) and neural response telemetry (NRT) after cochlear implant in children with inner ear malformation, and guide postoperative equipment debug. A total of 88 children with either normal cochlea (control group) or inner ear malformation (test group) received Australian 24 multi-channel cochlear implants. The EABR, ESRT and NRT thresholds at different time points within one year postoperatively and behavioral responses (T-level and C-level) after one year were detected. Furthermore, the changing characteristics and rules of these thresholds were analyzed. The EABR, ESRT and NRT thresholds were all significantly higher at all time points in the test group than in the control group, but the general changing trends were similar. Particularly, these thresholds worsened at low frequencies and improved at high frequencies. Furthermore, EABR, ESRT and NRT thresholds gradually increased during the one year postoperative period. In addition, an extremely significant correlation was found between EABR and T-level and between ESRT and C-level, but a less significant correlation was found between NRT threshold and T-level in both groups. The postoperative changes in characteristics and rules of EABR, ESRT and NRT thresholds among cochlear implant children with inner ear malformation were all the same as those with normal cochlea. Thus, these thresholds can be used to guide the postoperative equipment debug for cochlear implants into patients with inner ear malformation. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Piezoelectric materials mimic the function of the cochlear sensory epithelium.

    Science.gov (United States)

    Inaoka, Takatoshi; Shintaku, Hirofumi; Nakagawa, Takayuki; Kawano, Satoyuki; Ogita, Hideaki; Sakamoto, Tatsunori; Hamanishi, Shinji; Wada, Hiroshi; Ito, Juichi

    2011-11-08

    Cochlear hair cells convert sound vibration into electrical potential, and loss of these cells diminishes auditory function. In response to mechanical stimuli, piezoelectric materials generate electricity, suggesting that they could be used in place of hair cells to create an artificial cochlear epithelium. Here, we report that a piezoelectric membrane generated electrical potentials in response to sound stimuli that were able to induce auditory brainstem responses in deafened guinea pigs, indicating its capacity to mimic basilar membrane function. In addition, sound stimuli were transmitted through the external auditory canal to a piezoelectric membrane implanted in the cochlea, inducing it to vibrate. The application of sound to the middle ear ossicle induced voltage output from the implanted piezoelectric membrane. These findings establish the fundamental principles for the development of hearing devices using piezoelectric materials, although there are many problems to be overcome before practical application.

  7. Magnetic resonance imaging of the inner ear and its application to cochlear implant candidates

    Energy Technology Data Exchange (ETDEWEB)

    Irimoto, Masahiro (Toranomon Hospital, Tokyo (Japan))

    1991-05-01

    Magnetic resonance (MR) images of normal and abnormal inner ear obtained with a 1.5 T unit without the use of a surface coil were analyzed to evaluate the effectiveness of this method in the screening of cochlear implant candidates. In a series with sixteen normal adult volunteers, 22 to 45 years in age, 100% of the cochleae, vestibules, and lateral and posterior semicircular canals were clearly demonstrated in T{sub 2} weighted images. Satisfactory images were not obtained for 22% of the superior semicircular canals, 22% of the cochlear aqueduct, and 81% of the vestibular aqueduct in axial images, but coronal and sagittal reconstructed images by use of a three-dimensional Fourie transformation sequence provided better detectability of these structures. In five ear surgery patients with proven obliteration of the labyrinth, decreased signal intensity was observed in the T{sub 2} weighted images. Ten cochlear implant candidates were examined by MRI prior to implantation, and the results were compared with the surgical findings. In two ears in which the cochlea showed a decrease in signal intensity, the cochlea had been obliterated by inflammatory granulations. On the other hand, the lumens of all nine cochleae which were clearly visualized by MRI were found to be patent. (author).

  8. Physiological functioning of the ear and masking

    Science.gov (United States)

    1984-01-01

    The physiological functions of the ear and the role masking plays in speech communication are examined. Topics under investigation include sound analysis of the ear, the aural reflex, and various types of noise masking.

  9. Redundant functions of Rac GTPases in inner ear morphogenesis.

    Science.gov (United States)

    Grimsley-Myers, Cynthia M; Sipe, Conor W; Wu, Doris K; Lu, Xiaowei

    2012-02-15

    Development of the mammalian inner ear requires coordination of cell proliferation, cell fate determination and morphogenetic movements. While significant progress has been made in identifying developmental signals required for inner ear formation, less is known about how distinct signals are coordinated by their downstream mediators. Members of the Rac family of small GTPases are known regulators of cytoskeletal remodeling and numerous other cellular processes. However, the function of Rac GTPases in otic development is largely unexplored. Here, we show that Rac1 and Rac3 redundantly regulate many aspects of inner ear morphogenesis. While no morphological defects were observed in Rac3(-/-) mice, Rac1(CKO); Rac3(-/-) double mutants displayed enhanced vestibular and cochlear malformations compared to Rac1(CKO) single mutants. Moreover, in Rac1(CKO); Rac3(-/-) mutants, we observed compromised E-cadherin-mediated cell adhesion, reduced cell proliferation and increased cell death in the early developing otocyst, leading to a decreased size and malformation of the membranous labyrinth. Finally, cochlear extension was severely disrupted in Rac1(CKO); Rac3(-/-) mutants, accompanied by a loss of epithelial cohesion and formation of ectopic sensory patches underneath the cochlear duct. The compartmentalized expression of otic patterning genes within the Rac1(CKO); Rac3(-/-) mutant otocyst was largely normal, however, indicating that Rac proteins regulate inner ear morphogenesis without affecting cell fate specification. Taken together, our results reveal an essential role for Rac GTPases in coordinating cell adhesion, cell proliferation, cell death and cell movements during otic development. Copyright © 2011 Elsevier Inc. All rights reserved.

  10. Limits on normal cochlear 'third' windows provided by previous investigations of additional sound paths into and out of the cat inner ear.

    Science.gov (United States)

    Rosowski, John J; Bowers, Peter; Nakajima, Hideko H

    2018-03-01

    While most models of cochlear function assume the presence of only two windows into the mammalian cochlea (the oval and round windows), a position that is generally supported by several lines of data, there is evidence for additional sound paths into and out of the inner ear in normal mammals. In this report we review the existing evidence for and against the 'two-window' hypothesis. We then determine how existing data and inner-ear anatomy restrict transmission of sound through these additional sound pathways in cat by utilizing a well-tested model of the cat inner ear, together with anatomical descriptions of the cat cochlear and vestibular aqueducts (potential additional windows to the cochlea). We conclude: (1) The existing data place limits on the size of the cochlear and vestibular aqueducts in cat and are consistent with small volume-velocities through these ducts during ossicular stimulation of the cochlea, (2) the predicted volume velocities produced by aqueducts with diameters half the size of the bony diameters match the functional data within ±10 dB, and (3) these additional volume velocity paths contribute to the inner ear's response to non-acoustic stimulation and conductive pathology. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Modelling of the Human Inner Ear Anatomy and Variability for Cochlear Implant Applications

    DEFF Research Database (Denmark)

    Kjer, Hans Martin

    This thesis takes the biomedical engineering approach to working with and understanding the anatomy and physiology of the inner ear. The purpose is to apply the acquired knowledge in the development of implantable hearing aids. The so-called Cochlear Implant (CI) is a fascinating technology...... that without underselling it provides hearing for the deaf. The technology faces a number of challenges, and a part of the solution to those is closely connected with an improved understanding of the inner ear anatomy, both with regards to the individual patient but also to the variation in the population....... The inner ear is a relatively small structure and even with modern medical scanners only the coarsest details are revealed about the specific patient anatomy. To study the anatomy it is required to work on specimens from deceased subjects scanned with for instance μCT. The anatomy is complex and presents...

  12. Electrode Impedance Fluctuations as a Biomarker for Inner Ear Pathology After Cochlear Implantation.

    Science.gov (United States)

    Choi, June; Payne, Matthew R; Campbell, Luke J; Bester, Christo W; Newbold, Carrie; Eastwood, Hayden; O'Leary, Stephen J

    2017-12-01

    Cochlear implant surgery now aims to preserve residual low frequency hearing. The current research explores whether fluctuations in the electrical impedance of cochlear implant electrodes may act as a biomarker for pathological changes that lead to the delayed loss of residual hearing. Secondary analysis of a double-blinded randomized trial, where methylprednisolone was administered intravenously before cochlear implantation with a view to preserving residual hearing. Seventy-four patients with residual hearing after cochlear implant surgery were investigated for an impedance "spike," defined as a median rise of ≥4 kΩ across all electrodes from the baseline measurements. Spikes were related to objective and subjective hearing loss, dizziness, and tinnitus. An impedance spike occurred in 14% (10/74) of enrolled patients. Three months after surgery, five patients exhibited spikes and three of these patients had a total loss of their residual hearing. 4.3% of the 69 patients without spikes lost residual hearing. At 1 year, 9 of 10 patients who exhibited spikes had lost all their residual hearing. 8.1% of the 37 patients who did not experience a spike lost their residual hearing. Seventy percent of patients exhibiting a spike also experienced vertigo. The administration of steroids at the time of surgery did not influence the occurrence of spikes. Our results suggest that there is a relationship between a spike and the loss of residual hearing. It seems that rises in impedance can reflect pathology within the inner ear and predict the future loss of residual hearing.

  13. High-resolution MR imaging of the inner ear. Usefulness in cochlear implants

    Energy Technology Data Exchange (ETDEWEB)

    Kumakawa, Kozo

    1988-09-01

    The author investigated high-resolution MR imaging (MRI) of the inner ear and evaluated its usefulness in the selection of patients for cochlear implants. MRI was performed with a 1.5 T unit with the use of the head coil. The minimum thickness of the sections was 2.5 mm. T1- and T2-weighted images were obtained. The matrix size was 256 x 256, and the field of view was 15 cm. ECG-gating was introduced to eliminate motion artifacts. T2-weighted images could clearly delineate details of liquid containing labyrinth structures, including the cochlea, the vestible, the semicircular canals, and the internal auditory canal. With the proper use of T1 and T2 sequences, tissue characterization between lymph fluid and soft tissue could be obtained. This point was considered to be one of the greatest advantages of MRI over high-resolution CT in the diagnosis of inner ear disorders. The head coil technique seems to be superior to the surface coil technique in that it can generate homogeneous signal intensity, and therefore visual comparison of cochlea signals of both sides is possible under the same conditions. The author concluded that high-resolution MRI of the inner ear is useful for the preoperative assessment of cochlear implant candidates in order to rule out soft tissue occlusion of the cochlea, which cannot be diagnosed even by high-resolution CT.

  14. Preservation of cochlear function in Cd39 deficient mice.

    Science.gov (United States)

    Vlajkovic, Srdjan M; Housley, Gary D; Thorne, Peter R; Gupta, Rita; Enjyoji, Keiichi; Cowan, Peter J; Charles Liberman, M; Robson, Simon C

    2009-07-01

    Signalling actions of extracellular nucleotides via P2 receptors influence cellular function in most tissues. In the inner ear, P2 receptor signaling is involved in many processes including the regulation of hearing sensitivity and the cochlea's response to noise stress. CD39 (NTPDase1/ENTPD1) is an ectonucleotidase (ecto-nucleoside triphosphate diphosphohydrolase) that can hydrolyse purine and pyrimidine nucleoside tri- and di-phosphates to generate monophosphate nucleosides. Mice null for Cd39 exhibit major alterations in haemostasis and profound alterations in inflammatory and thrombotic reactions. Studies in the cochlea have suggested the involvement of purinergic-type signals that could be modulated by CD39 in regulation of cochlear blood flow and also auditory neurotransmission. This study aimed to determine the auditory phenotype of adult Cd39 null mice on the C57BL6 background. Auditory brainstem responses (ABR) and distortion product otoacoustic emissions (DPOAE) were unaffected in Cd39-deficient mice across the range of test frequencies, suggesting normal neural and outer hair cell function. Mutant mice also showed little difference to wild type mice in vulnerability to acoustic trauma. Gene expression analysis of other membrane-bound NTPDases with comparable hydrolytic activity demonstrated an up-regulation of Entpd2 and Entpd8 in the cochleae of Cd39 deficient mice. These findings suggest that Cd39 deletion alone does not adversely affect cochlear function, possibly as compensatory up-regulation of other surface located NTPDases may offset predicted alterations in cochlear homeostasis.

  15. Cochlear function tests in estimation of speech dynamic range.

    Science.gov (United States)

    Han, Jung Ju; Park, So Young; Park, Shi Nae; Na, Mi Sun; Lee, Philip; Han, Jae Sang

    2016-10-01

    The loss of active cochlear mechanics causes elevated thresholds, loudness recruitment, and reduced frequency selectivity. The problems faced by hearing-impaired listeners are largely related with reduced dynamic range (DR). The aim of this study was to determine which index of the cochlear function tests correlates best with the DR to speech stimuli. Audiological data on 516 ears with pure tone average (PTA) of ≤55 dB and word recognition score of ≥70% were analyzed. PTA, speech recognition threshold (SRT), uncomfortable loudness (UCL), and distortion product otoacoustic emission (DPOAE) were explored as the indices of cochlear function. Audiometric configurations were classified. Correlation between each index and the DR was assessed and multiple regression analysis was done. PTA and SRT demonstrated strong negative correlations with the DR (r = -0.788 and -0.860, respectively), while DPOAE sum was moderately correlated (r = 0.587). UCLs remained quite constant for the total range of the DR. The regression equation was Y (DR) = 75.238 - 0.719 × SRT (R(2 )=( )0.721, p equation.

  16. Image analysis of the inner ear with CT and MR imaging; Pre-operative assessment for cochlear implant surgery

    Energy Technology Data Exchange (ETDEWEB)

    Kumakawa, Kohzoh; Takeda, Hidehiko; Mutoh, Naoko; Miyakawa, Kohichi (Toranomon Hospital, Tokyo (Japan)); Yukawa, Kumiko; Funasaka, Sohtaro

    1992-06-01

    Recent progress in magnetic resonance imaging (MRI) has made it possible to obtain detailed images of the inner ear by delineating the lymphatic fluid within the labyrinth. We analyzed CT scans and MR imaging in 70 ears manifesting profound deafness owing to inner ear lesions and compared their detective ability for inner ear lesions. The following results were obtained. CT scan examination showed slight to extensive ossification of the labyrinth in six ears (9%), whereas MRI examination revealed low to absent signal intensity of the inner ear in nine ears (13%). Therefore, it was concluded that MRI is more sensitive in detecting abnormalities of the inner ear than CT scan. MRI provided useful information as to whether the cochlear turn is filled with lymphatic fluid or obstructed. This point was one of the greatest advantages of MRI over CT scan. Abnormal findings in either or both the CT scan and the MRI were detected in suppurative labyrinthitis occurring secondary to chronic otitis media, bacterial meningitis and in inner ear trauma. However, such abnormal findings were not detected in patients with idiopathic progressive sensorineural hearing loss, ototoxity or sudden deafness. These findings should be taken into consideration in pre-operative assessment of cochlear implant candidates. (author).

  17. Evaluation of Saccular Function Pre-Post Cochlear Implant Surgery Using VEMPs

    Directory of Open Access Journals (Sweden)

    Yones Lotfi

    2015-12-01

    Full Text Available Objectives: The aim of present study was evaluation of saccule function in cochlear implant candidates with severe to profound sensory neural hearing loss Before and after cochlear implantation Methods: In this study 35 cochlear implant (CI candidates with bilateral severe to profound sensory neural hearing loss before and about 30 days after cochlear implant and 20 normal-hearing cases as a control group underwent VEMP test. Both groups were matched based on gender and age. Results: VEMP responses were absent bilaterally in 10 out of 35 patients. 4 patients were excluded from the study because they did not receive CI during present study. From 21 remaining patients, 5 cases lost VEMP responses in their implanted ear after surgery. In control group, VEMP responses were present bilaterally. Discussion: The results of present study indicate that saccule dysfunction in CI candidates is extremely probable and this is possible that saccule get impaired after CI.

  18. 3D finite element model of the chinchilla ear for characterizing middle ear functions

    OpenAIRE

    Wang, Xuelin; Gan, Rong Z.

    2016-01-01

    Chinchilla is a commonly used animal model for research of sound transmission through the ear. Experimental measurements of the middle ear transfer function in chinchillas have shown that the middle ear cavity greatly affects the tympanic membrane (TM) and stapes footplate (FP) displacements. However, there is no finite element (FE) model of the chinchilla ear available in the literature to characterize the middle ear functions with the anatomical features of the chinchilla ear. This paper re...

  19. Perception of Suprasegmental Speech Features via Bimodal Stimulation: Cochlear Implant on One Ear and Hearing Aid on the Other

    Science.gov (United States)

    Most, Tova; Harel, Tamar; Shpak, Talma; Luntz, Michal

    2011-01-01

    Purpose: The purpose of the study was to evaluate the contribution of acoustic hearing to the perception of suprasegmental features by adults who use a cochlear implant (CI) and a hearing aid (HA) in opposite ears. Method: 23 adults participated in this study. Perception of suprasegmental features--intonation, syllable stress, and word…

  20. 3D finite element model of the chinchilla ear for characterizing middle ear functions.

    Science.gov (United States)

    Wang, Xuelin; Gan, Rong Z

    2016-10-01

    Chinchilla is a commonly used animal model for research of sound transmission through the ear. Experimental measurements of the middle ear transfer function in chinchillas have shown that the middle ear cavity greatly affects the tympanic membrane (TM) and stapes footplate (FP) displacements. However, there is no finite element (FE) model of the chinchilla ear available in the literature to characterize the middle ear functions with the anatomical features of the chinchilla ear. This paper reports a recently completed 3D FE model of the chinchilla ear based on X-ray micro-computed tomography images of a chinchilla bulla. The model consisted of the ear canal, TM, middle ear ossicles and suspensory ligaments, and the middle ear cavity. Two boundary conditions of the middle ear cavity wall were simulated in the model as the rigid structure and the partially flexible surface, and the acoustic-mechanical coupled analysis was conducted with these two conditions to characterize the middle ear function. The model results were compared with experimental measurements reported in the literature including the TM and FP displacements and the middle ear input admittance in chinchilla ear. An application of this model was presented to identify the acoustic role of the middle ear septa-a unique feature of chinchilla middle ear cavity. This study provides the first 3D FE model of the chinchilla ear for characterizing the middle ear functions through the acoustic-mechanical coupled FE analysis.

  1. Congenital malformations of the ear and cochlear implantation in children: review and temporal bone report of common cavity.

    Science.gov (United States)

    Graham, J M; Phelps, P D; Michaels, L

    2000-01-01

    The objective of this review is to analyze aspects of congenital malformation of the ear in relation to cochlear implantation in children. Having briefly described the in utero development of the ear and the classification of types of external, middle and inner ear malformation, five practical aspects of these malformations are discussed. It seems likely that the combination of bilateral profound sensorineural deafness with bilateral microtia severe enough to make a surgical approach to the cochlea difficult will be extremely uncommon. No such cases have been reported, although Klippel-Feil deformity seems the syndrome most likely to produce this set of circumstances. Abnormalities in the intratympanic course of the facial nerve have been associated with cochlear malformation, emphasizing the benefit of intra-operative facial nerve monitoring, and a technique suggested for safely avoiding an abnormally placed nerve. Fistulae of cerebrospinal fluid (CSF) and perilymph can complicate surgery and are relatively common in common cavity and Mondini malformations. Strategies for facilitating surgery in the presence of 'gushers', for measuring the pressure of a gusher and for placement of the cochlear implant electrode array are reviewed, with reports of fluctuating levels of electric current when implants lie in dysplastic cochleas. The relationship of implant performance to VIIIth nerve tissue in malformed cochleas is discussed, with a description of the histological findings in a common cavity cochlea. Techniques for identifying the absence of the cochlear nerve are reviewed. Stimulation of the facial nerve by cochlear implants has been described in cases of congenital malformation of the labyrinth but is relatively uncommon. Case reports of the benefit received by implanted children with congenital cochlear malformation have appeared since 1988. Most cases reported have not yet been followed for long enough to establish a clear picture of the outcome following

  2. PCB exposure and cochlear function at age 6 years.

    Science.gov (United States)

    Palkovičová Murínová, Ľubica; Moleti, Arturo; Sisto, Renata; Wimmerová, Soňa; Jusko, Todd A; Tihányi, Juraj; Jurečková, Dana; Kováč, Ján; Koštiaková, Vladimíra; Drobná, Beata; Trnovec, Tomáš

    2016-11-01

    Epidemiological studies have documented adverse associations between exposure to polychlorinated biphenyls (PCBs) and otological outcomes. Previously, we documented decreased distortion product otoacoustic emission (DPOAE) levels in children exposed to PCBs, up to the age of 45 months, amongst a cohort of children in eastern Slovakia. The objective of the present study is to evaluate cochlear dysfunction at 72 months of age in 214 children from this same cohort and to compare the otoacoustic test sensitivity to that of pure tone audiometry (PTA). The association between DPOAE, PTA, and PCBs was estimated by means of multivariate ANOVA (MANOVA) and linear regression models. ROC curves were computed to estimate the DPOAE-test power in children. The DPOAE level at 72 months was related to PCB-153 serum levels. The DPOAE Input/Output function test at mid-frequency (2kHz) has shown instead nonmonotonic dependence on PCB exposure, for the left ears of children, over the whole growth curve. No significant association was found between PTA hearing levels and PCB-153 concentration. High diagnostic power of the DPOAE-test was found in children, similar to that found by the same authors in adults. In conclusions the DPOAE-PCB correlation obtained at 72 months is similar to that at 45 months suggesting a permanent and stable ototoxic effect of the PCB exposure. The lack of statistical significance of the PCB-PTA correlation suggests that DPOAEs are sensitive biomarkers of cochlear damage. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. [Functional model of the middle ear ossicles].

    Science.gov (United States)

    Satoda, Takahiro; Shimoe, Saiji; Makihira, Seicho; Tamamoto, Mitsuhiro; Matsumoto, Atsue; Hara, Kumiko; Noso, Maki; Niitani, Yoshie; Sugiyama, Masaru; Takemoto, Toshinobu; Murayama, Takeshi; Amano, Hideaki; Nikawa, Hiroki

    2009-06-01

    In students' dissection practice, it is very difficult to teach students the structures and functions of the middle ear ossicles. The middle ear ossicles are too small to explain their structures and functions. Models are useful in explaining these points, but there have been no models that accurately explain the movements of the middle ear ossicles and the functions of the muscles in the middle ear. This time, we have made a model of middle ear ossicles. Our ear ossicles are made of paper-mache with metal in it. The incudomalleolar and incudostapedial articulations are made of rubber. The tensor tympani and the stapedius muscles are made of wire and the two wires can be fixed by cord stoppers. Our model explains clearly the following mechanisms of the middle ear ossicles. 1. The mechanism of sound conduction system. When the sound vibrates the tympanic membrane, malleus and incus rotate together. The long process of the incus pushes the head of the stapes. The sound is amplified by leverage. 2. Attenuation of sound by contractions of tensor tympani and stapedius muscles. When a loud sound is transmitted through the ossicular system, the tensor tympani muscle pulls the malleus inward while the stapedius muscle pulls the stapes outward. These two forces oppose each other and increase rigidity of the ossicular system, thus reducing the ossicular conduction. 3. The mechanism of how paralysis of stapedius muscle, caused by an injury to the facial nerve, results in hyperacusis. 4. This model also suggests a possible reason why the pars lucida of the tympanic membrane exists.

  4. Audiological Outcomes and Map Characteristics in Children With Perimodiolar and Slim Straight Array Cochlear Implants in Opposite Ears.

    Science.gov (United States)

    Park, Lisa R; Teagle, Holly F B; Brown, Kevin D; Gagnon, Erika B; Woodard, Jennifer S; Buchman, Craig A

    2017-10-01

    To identify differences in outcomes and map characteristics in pediatric bilateral cochlear implants with modiolar conforming and lateral wall arrays in opposite ears. Retrospective case series. Tertiary care pediatric referral center. Fourteen children who received a perimodiolar array in one ear and a slim straight array in the opposite ear in sequential surgeries. None. Consonant-nucleus-consonant test (CNC) word recognition score, battery life, power levels, electrical compound action potential (ECAP) thresholds, and electrical threshold and comfort charge levels. Speech perception outcomes were poorer in the lateral wall ears than the perimodiolar ears, and scores in the bilateral condition were better than with the lateral wall device alone. Sequential placement was a factor with differences in preoperative candidacy time correlating with greater difference in speech perception. There was no difference in charge levels between ears, in spite of higher ECAP threshold values for the lateral wall devices. While bilateral speech perception was good, speech perception with the lateral wall device alone was poorer. This cannot be explained solely by the device, as differences in preoperative candidacy time were a significant factor. ECAP thresholds are significantly higher for lateral wall electrodes, but that did not translate in to higher psychophysical measurements.

  5. Bilateral sequential cochlear implantation in the congenitally deaf child: evidence to support the concept of a 'critical age' after which the second ear is less likely to provide an adequate level of speech perception on its own.

    Science.gov (United States)

    Graham, John; Vickers, Debi; Eyles, Julie; Brinton, Julie; Al Malky, Ghada; Aleksy, Wanda; Martin, Jane; Henderson, Lise; Mawman, Deborah; Robinson, Philip; Midgley, Elizabeth; Hanvey, Kate; Twomey, Tracey; Johnson, Susan; Vanat, Zebunnisa; Broxholme, Cath; McAnallen, Cecilia; Allen, Agnes; Bray, Monica

    2009-09-01

    This study attempts to answer the question of whether there is a 'critical age' after which a second contralateral cochlear implant is less likely to provide enough speech perception to be of practical use. The study was not designed to predict factors that determine successful binaural implant use, but to see if there was evidence to help determine the latest age at which the second ear can usefully be implanted, should the first side fail and become unusable.Outcome data, in the form of speech perception test results, were collected from 11 cochlear implant programmes in the UK and one centre in Australia. Forty-seven congenitally bilaterally deaf subjects who received bilateral sequential implants were recruited to the study. The study also included four subjects with congenital unilateral profound deafness who had lost all hearing in their only hearing ear and received a cochlear implant in their unilaterally congenitally deaf ear. Of those 34 subjects for whom complete sets of data were available, the majority (72%) of those receiving their second (or unilateral) implant up to the age of 13 years scored 60 per cent or above in the Bamford Kowal Bench (BKB) sentence test, or equivalent. In contrast, of those nine receiving their second or unilateral implant at the age of 15 or above, none achieved adequate levels of speech perception on formal testing: two scored 29 per cent and 30 per cent, respectively, and the rest seven per cent or less.A discriminant function analysis performed on the data suggests that it is unlikely that a second contralateral implant received after the age of 16 to 18 years will, on its own, provide adequate levels of speech perception. As more children receive sequential bilateral cochlear implants and the pool of data enlarges the situation is likely to become clearer.The results provide support for the concept of a 'critical age' for implanting the second ear in successful congenitally deaf unilateral cochlear implant users. This

  6. Middle ear function in sinonasal polyposis.

    Science.gov (United States)

    Bakhshaee, Mehdi; Ardakani, Hossein Payedar; Ghazizadeh, Amir Hossain; Movahed, Rahman; Jarahi, Lida; Rajati, Mohsen

    2016-10-01

    Nasal airway patency has long been considered a major factor in ear health. The aim of this study was to determine the effect of sinonasal polyposis on middle ear and eustachian tube (ET) functionality. Forty-four individuals with polyposis, 23 with non-polyposis nasal obstruction, and 23 healthy controls were enrolled. Demographic, clinical and imaging data of all participants were collected and ET function tests and audiologic tests were performed. Hearing loss (p = 0.02), flat tympanogram (p = 0.02), disturbed Toynbee and Valsalva tests (p = 0.01), and the prevalence of allergy (p = 0.04) and purulent nasal discharge (p polyposis group than the other groups. Regression analysis revealed that infection and allergy have more important roles in ET function than the nasal obstruction. Polyposis could impede ET function; however, it is probably not because of its obstructive nature, but because of the associated increased risk of infection.

  7. Impact of Jacobson's (tympanic) nerve sectioning on middle ear functions.

    Science.gov (United States)

    Ceylan, Alper; Göksu, Nebil; Kemaloğlu, Yusuf Kemal; Uğur, Birol; Akyürek, Nalan; Bayazit, Yildirim A

    2007-04-01

    The purpose of this study was to evaluate the influence of sectioning of the Jacobson's (tympanic) nerve on middle ear functions. Twenty-five adult New Zealand rabbits were included in this study. The Jacobson's nerve was cut in the left ear of the rabbits (study group), whereas only a small mucosal incision was performed while keeping the Jacobson's nerve intact in their right ear (control group). After the operation, the ears were assessed both otomicroscopically and histopathologically on Days 30, 60, and 90. On otomicroscopy, retraction pockets were observed in 48 and 4% of the ears in the study and control groups, respectively (p ear effusion was observed in 56 and 12%, respectively (p ear mucosa was present in all ears in the study group, whereas it was present only in 20% of the control ears (p ear chemosensory organs and are involved in the regulation of middle ear aeration. Disruption of these neural elements such as Jacobson's nerve negatively impacts on middle ear functions and may result in atelectasis.

  8. Evaluation of hearing and cochlear function by audiometric testing in patients with hyperemesis gravidarum.

    Science.gov (United States)

    Kale, Ahmet; Yavuz, Arzu; Selçuk, Adin; Demirtas, Ömer; Terzi, Hasan; Genç, Selahattin

    2015-01-01

    The aim of this study was to investigate cochlear functions in patients with hyperemesis gravidarum (HG). Twenty-nine HG patients (58 ears) and 31 healthy control subjects (62 ears) were included. Audiometry testings at 250 and 500 Hz and 1, 2, 4, 8, 10, 12, 14, 16 kHz were performed to the patients and controls. Mean age of patients with HG was 26,5 ± 4,4 years and the mean age of control group was 28,0 ± 4,2 years. At the time of the tests mean gestational age of the HG group and controls were 9 and 11 weeks respectively. No differences were observed between the groups in tympanic membrane status, or other otolaringological evaluations. No significant differences were observed in audiometric tests at any frequencies between the groups (p values for all > 0.05). There was not a difference between pregnant cases with HG and cases with normal pregnancy in terms of audimetric tests. Cochlear functions are not affected remarkably in women with HG.

  9. Improvement of cognitive function after cochlear implantation in elderly patients.

    Science.gov (United States)

    Mosnier, Isabelle; Bebear, Jean-Pierre; Marx, Mathieu; Fraysse, Bernard; Truy, Eric; Lina-Granade, Geneviève; Mondain, Michel; Sterkers-Artières, Françoise; Bordure, Philippe; Robier, Alain; Godey, Benoit; Meyer, Bernard; Frachet, Bruno; Poncet-Wallet, Christine; Bouccara, Didier; Sterkers, Olivier

    2015-05-01

    The association between hearing impairment and cognitive decline has been established; however, the effect of cochlear implantation on cognition in profoundly deaf elderly patients is not known. To analyze the relationship between cognitive function and hearing restoration with a cochlear implant in elderly patients. Prospective longitudinal study performed in 10 tertiary referral centers between September 1, 2006, and June 30, 2009. The participants included 94 patients aged 65 to 85 years with profound, postlingual hearing loss who were evaluated before, 6 months after, and 12 months after cochlear implantation. Cochlear implantation and aural rehabilitation program. Speech perception was measured using disyllabic word recognition tests in quiet and in noise settings. Cognitive function was assessed using a battery of 6 tests evaluating attention, memory, orientation, executive function, mental flexibility, and fluency (Mini-Mental State Examination, 5-word test, clock-drawing test, verbal fluency test, d2 test of attention, and Trail Making test parts A and B). Quality of life and depression were evaluated using the Nijmegen Cochlear Implant Questionnaire and the Geriatric Depression Scale-4. Cochlear implantation led to improvements in speech perception in quiet and in noise (at 6 months: in quiet, 42% score increase [95% CI, 35%-49%; P tests. One year after implant, 81% of the subgroup (30 of 37) showed improved global cognitive function (no or 1 abnormal test score). Improved mean scores in all cognitive domains were observed as early as 6 months after cochlear implantation. Cognitive performance remained stable in the remaining 19% of the participants (7 of 37). Among patients with the best cognitive performance before implantation (ie, no or 1 abnormal cognitive test score), 24% (12 of 50) displayed a slight decline in cognitive performance. Multivariate analysis to examine the association between cognitive abilities before implantation and the

  10. Probing the Xenopus laevis inner ear transcriptome for biological function

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    Powers TuShun R

    2012-06-01

    Full Text Available Abstract Background The senses of hearing and balance depend upon mechanoreception, a process that originates in the inner ear and shares features across species. Amphibians have been widely used for physiological studies of mechanotransduction by sensory hair cells. In contrast, much less is known of the genetic basis of auditory and vestibular function in this class of animals. Among amphibians, the genus Xenopus is a well-characterized genetic and developmental model that offers unique opportunities for inner ear research because of the amphibian capacity for tissue and organ regeneration. For these reasons, we implemented a functional genomics approach as a means to undertake a large-scale analysis of the Xenopus laevis inner ear transcriptome through microarray analysis. Results Microarray analysis uncovered genes within the X. laevis inner ear transcriptome associated with inner ear function and impairment in other organisms, thereby supporting the inclusion of Xenopus in cross-species genetic studies of the inner ear. The use of gene categories (inner ear tissue; deafness; ion channels; ion transporters; transcription factors facilitated the assignment of functional significance to probe set identifiers. We enhanced the biological relevance of our microarray data by using a variety of curation approaches to increase the annotation of the Affymetrix GeneChip® Xenopus laevis Genome array. In addition, annotation analysis revealed the prevalence of inner ear transcripts represented by probe set identifiers that lack functional characterization. Conclusions We identified an abundance of targets for genetic analysis of auditory and vestibular function. The orthologues to human genes with known inner ear function and the highly expressed transcripts that lack annotation are particularly interesting candidates for future analyses. We used informatics approaches to impart biologically relevant information to the Xenopus inner ear transcriptome

  11. Which ear should we choose for cochlear implantation in the elderly: The poorer or the better? Audiometric outcomes, quality of sound, and quality-of-life results.

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    Lassaletta, Luis; Calvino, Miryam; Sánchez-Cuadrado, Isabel; Pérez-Mora, Rosa M; Gavilán, Javier

    2015-01-01

    Cochlear implantation in the poorer ear of an elderly patient does not predict poorer post-operative audiological, quality-of-life (QoL), and quality of sound results. To determine whether choosing the 'better' or the 'poorer' ear for cochlear implantation impacts performance outcome in an elderly population. Forty-two out of 73 elderly (≥ 60 years) cochlear implant users with some residual hearing in at least one ear were selected. Three criteria were used to group the patients as 'better' or 'poorer' ear implanted; (C1) based on previous use of hearing aid, (C2) pre-operative PTA, and (C3) pre-operative speech discrimination. The Glasgow Benefit Inventory (GBI) and the Hearing Implant Sound Quality Index (HISQUI) were used to measure QoL and quality of sound, respectively. The mean post-operative PTA was 38.7 ± 7.2 dBHL. In quiet, the mean disyllabic SDS at 65dBSPL was 75.4 ± 18.5, whereas the discrimination of sentences was 95.0% ± 6.9. The mean total GBI score was 30.9 ± 21.8, 92.9% of patients reporting a positive score. The mean HISQUI score was 111.3 ± 36.0, which corresponds to 'moderate' sound quality. No significant differences were found between both groups in terms of audiological outcomes, HISQUI scores or GBI scores when considering each of the three criteria.

  12. Off the ear with no loss in speech understanding: comparing the RONDO and the OPUS 2 cochlear implant audio processors.

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    Dazert, Stefan; Thomas, Jan Peter; Büchner, Andreas; Müller, Joachim; Hempel, John Martin; Löwenheim, Hubert; Mlynski, Robert

    2017-03-01

    The RONDO is a single-unit cochlear implant audio processor, which omits the need for a behind-the-ear (BTE) audio processor. The primary aim was to compare speech perception results in quiet and in noise with the RONDO and the OPUS 2, a BTE audio processor. Secondary aims were to determine subjects' self-assessed levels of sound quality and gather subjective feedback on RONDO use. All speech perception tests were performed with the RONDO and the OPUS 2 behind-the-ear audio processor at 3 test intervals. Subjects were required to use the RONDO between test intervals. Subjects were tested at upgrade from the OPUS 2 to the RONDO and at 1 and 6 months after upgrade. Speech perception was determined using the Freiburg Monosyllables in quiet test and the Oldenburg Sentence Test (OLSA) in noise. Subjective perception was determined using the Hearing Implant Sound Quality Index (HISQUI 19 ), and a RONDO device-specific questionnaire. 50 subjects participated in the study. Neither speech perception scores nor self-perceived sound quality scores were significantly different at any interval between the RONDO and the OPUS 2. Subjects reported high levels of satisfaction with the RONDO. The RONDO provides comparable speech perception to the OPUS 2 while providing users with high levels of satisfaction and comfort without increasing health risk. The RONDO is a suitable and safe alternative to traditional BTE audio processors.

  13. Notch ligands with contrasting functions: Jagged1 and Delta1 in the mouse inner ear.

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    Brooker, Rachael; Hozumi, Katsuto; Lewis, Julian

    2006-04-01

    Each of the sensory patches in the epithelium of the inner ear is a mosaic of hair cells and supporting cells. Notch signalling is thought to govern this pattern of differentiation through lateral inhibition. Recent experiments in the chick suggest, however, that Notch signalling also has a prior function - inductive rather than inhibitory - in defining the prosensory patches from which the differentiated cells arise. Several Notch ligands are expressed in each patch, but their individual roles in relation to the two functions of Notch signalling are unclear. We have used a Cre-LoxP approach to knock out two of these ligands, Delta1 (Dll1) and Jagged1 (Jag1), in the mouse ear. In the absence of Dll1, auditory hair cells develop early and in excess, in agreement with the lateral inhibition hypothesis. In the absence of Jag1, by contrast, the total number of these cells is strongly reduced, with complete loss of cochlear outer hair cells and some groups of vestibular hair cells, indicating that Jag1 is required for the prosensory inductive function of Notch. The number of cochlear inner hair cells, however, is almost doubled. This correlates with loss of expression of the cell cycle inhibitor p27(Kip1) (Cdkn1b), suggesting that signalling by Jag1 is also needed to limit proliferation of prosensory cells, and that there is a core part of this population whose prosensory character is established independently of Jag1-Notch signalling. Our findings confirm that Notch signalling in the ear has distinct prosensory and lateral-inhibitory functions, for which different ligands are primarily responsible.

  14. Inverse solution of ear-canal area function from reflectance.

    Science.gov (United States)

    Rasetshwane, Daniel M; Neely, Stephen T

    2011-12-01

    A number of acoustical applications require the transformation of acoustical quantities, such as impedance and pressure that are measured at the entrance of the ear canal, to quantities at the eardrum. This transformation often requires knowledge of the shape of the ear canal. Previous attempts to measure ear-canal area functions were either invasive, non-reproducible, or could only measure the area function up to a point mid-way along the canal. A method to determine the area function of the ear canal from measurements of acoustic impedance at the entrance of the ear canal is described. The method is based on a solution to the inverse problem in which measurements of impedance are used to calculate reflectance, which is then used to determine the area function of the canal. The mean ear-canal area function determined using this method is similar to mean ear-canal area functions measured by other researchers using different techniques. The advantage of the proposed method over previous methods is that it is non- invasive, fast, and reproducible. © 2011 Acoustical Society of America

  15. Inverse solution of ear-canal area function from reflectance

    OpenAIRE

    Rasetshwane, Daniel M.; Neely, Stephen T.

    2011-01-01

    A number of acoustical applications require the transformation of acoustical quantities, such as impedance and pressure that are measured at the entrance of the ear canal, to quantities at the eardrum. This transformation often requires knowledge of the shape of the ear canal. Previous attempts to measure ear-canal area functions were either invasive, non-reproducible, or could only measure the area function up to a point mid-way along the canal. A method to determine the area function of the...

  16. The kidney and ear: emerging parallel functions.

    Science.gov (United States)

    Torban, Elena; Goodyer, Paul

    2009-01-01

    The association between renal dysplasia and minor malformations of the external ear is weak. However, there is a remarkable list of syndromes that link the kidney to the inner ear. To organize these seemingly disparate syndromes, we cluster representative examples into three groups: (a) syndromes that share pathways regulating development; (b) syndromes involving dysfunction of the primary cilium, which normally provides critical information to epithelial cells about the fluid in which they are bathed; (c) syndromes arising from dysfunction of specialized proteins that transport ions and drugs in and out of the extracellular fluid or provide structural support.

  17. The dolphin cochlear nucleus: topography, histology and functional implications.

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    Malkemper, E P; Oelschläger, H H A; Huggenberger, S

    2012-02-01

    Despite the outstanding auditory capabilities of dolphins, there is only limited information available on the cytology of the auditory brain stem nuclei in these animals. Here, we investigated the cochlear nuclei (CN) of five brains of common dolphins (Delphinus delphis) and La Plata dolphins (Pontoporia blainvillei) using cell and fiber stain microslide series representing the three main anatomical planes. In general, the CN in dolphins comprise the same set of subnuclei as in other mammals. However, the volume ratio of the dorsal cochlear nucleus (DCN) in relation to the ventral cochlear nucleus (VCN) of dolphins represents a minimum among the mammals examined so far. Because, for example, in cats the DCN is necessary for reflexive orientation of the head and pinnae towards a sound source, the massive restrictions in head movability in dolphins and the absence of outer ears may be correlated with the reduction of the DCN. Moreover, the same set of main neuron types were found in the dolphin CN as in other mammals, including octopus and multipolar cells. Because the latter two types of neurons are thought to be involved in the recognition of complex sounds, including speech, we suggest that, in dolphins, they may be involved in the processing of their communication signals. Comparison of the toothed whale species studied here revealed that large spherical cells were present in the La Plata dolphin but absent in the common dolphin. These neurons are known to be engaged in the processing of low-frequency sounds in terrestrial mammals. Accordingly, in the common dolphin, the absence of large spherical cells seems to be correlated with a shift of its auditory spectrum into the high-frequency range above 20 kHz. The existence of large spherical cells in the VCN of the La Plata dolphin, however, is enigmatic asthis species uses frequencies around 130 kHz. Copyright © 2011 Wiley Periodicals, Inc.

  18. In vivo analysis of Lrig genes reveals redundant and independent functions in the inner ear.

    Science.gov (United States)

    Del Rio, Tony; Nishitani, Allison M; Yu, Wei-Ming; Goodrich, Lisa V

    2013-01-01

    Lrig proteins are conserved transmembrane proteins that modulate a variety of signaling pathways from worm to humans. In mammals, there are three family members - Lrig1, Lrig2, and Lrig3--that are defined by closely related extracellular domains with a similar arrangement of leucine rich repeats and immunoglobulin domains. However, the intracellular domains show little homology. Lrig1 inhibits EGF signaling through internalization and degradation of ErbB receptors. Although Lrig3 can also bind ErbB receptors in vitro, it is unclear whether Lrig2 and Lrig3 exhibit similar functions to Lrig1. To gain insights into Lrig gene functions in vivo, we compared the expression and function of the Lrigs in the inner ear, which offers a sensitive system for detecting effects on morphogenesis and function. We find that all three family members are expressed in the inner ear throughout development, with Lrig1 and Lrig3 restricted to subsets of cells and Lrig2 expressed more broadly. Lrig1 and Lrig3 overlap prominently in the developing vestibular apparatus and simultaneous removal of both genes disrupts inner ear morphogenesis. This suggests that these two family members act redundantly in the otic epithelium. In contrast, although Lrig1 and Lrig2 are frequently co-expressed, Lrig1(-/-);Lrig2(-/-) double mutant ears show no enhanced structural abnormalities. At later stages, Lrig1 expression is sustained in non-sensory tissues, whereas Lrig2 levels are enhanced in neurons and sensory epithelia. Consistent with these distinct expression patterns, Lrig1 and Lrig2 mutant mice exhibit different forms of impaired auditory responsiveness. Notably, Lrig1(-/-);Lrig2(-/-) double mutant mice display vestibular deficits and suffer from a more severe auditory defect that is accompanied by a cochlear innervation phenotype not present in single mutants. Thus, Lrig genes appear to act both redundantly and independently, with Lrig2 emerging as the most functionally distinct family member.

  19. In vivo analysis of Lrig genes reveals redundant and independent functions in the inner ear.

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    Tony Del Rio

    Full Text Available Lrig proteins are conserved transmembrane proteins that modulate a variety of signaling pathways from worm to humans. In mammals, there are three family members - Lrig1, Lrig2, and Lrig3--that are defined by closely related extracellular domains with a similar arrangement of leucine rich repeats and immunoglobulin domains. However, the intracellular domains show little homology. Lrig1 inhibits EGF signaling through internalization and degradation of ErbB receptors. Although Lrig3 can also bind ErbB receptors in vitro, it is unclear whether Lrig2 and Lrig3 exhibit similar functions to Lrig1. To gain insights into Lrig gene functions in vivo, we compared the expression and function of the Lrigs in the inner ear, which offers a sensitive system for detecting effects on morphogenesis and function. We find that all three family members are expressed in the inner ear throughout development, with Lrig1 and Lrig3 restricted to subsets of cells and Lrig2 expressed more broadly. Lrig1 and Lrig3 overlap prominently in the developing vestibular apparatus and simultaneous removal of both genes disrupts inner ear morphogenesis. This suggests that these two family members act redundantly in the otic epithelium. In contrast, although Lrig1 and Lrig2 are frequently co-expressed, Lrig1(-/-;Lrig2(-/- double mutant ears show no enhanced structural abnormalities. At later stages, Lrig1 expression is sustained in non-sensory tissues, whereas Lrig2 levels are enhanced in neurons and sensory epithelia. Consistent with these distinct expression patterns, Lrig1 and Lrig2 mutant mice exhibit different forms of impaired auditory responsiveness. Notably, Lrig1(-/-;Lrig2(-/- double mutant mice display vestibular deficits and suffer from a more severe auditory defect that is accompanied by a cochlear innervation phenotype not present in single mutants. Thus, Lrig genes appear to act both redundantly and independently, with Lrig2 emerging as the most functionally distinct

  20. Wideband acoustic transfer functions predict middle-ear effusion.

    Science.gov (United States)

    Ellison, John C; Gorga, Michael; Cohn, Edward; Fitzpatrick, Denis; Sanford, Chris A; Keefe, Douglas H

    2012-04-01

    Compare the accuracy of wideband acoustic transfer functions (WATFs) measured in the ear canal at ambient pressure to methods currently recommended by clinical guidelines for predicting middle-ear effusion (MEE). Cross-sectional validating diagnostic study among young children with and without MEE to investigate the ability of WATFs to predict MEE. WATF measures were obtained in an MEE group of 44 children (53 ears; median age, 1.3 years) scheduled for middle-ear ventilation tube placement and a normal age-matched control group of 44 children (59 ears; median age, 1.2 years) with normal pneumatic otoscopic findings and no history of ear disease or middle-ear surgery. An otolaryngologist judged whether MEE was present or absent and rated tympanic-membrane (TM) mobility via pneumatic otoscopy. A likelihood-ratio classifier reduced WATF data (absorbance, admittance magnitude and phase) from 0.25 to 8 kHz to a single predictor of MEE status. Absorbance was compared to pneumatic otoscopy classifications of TM mobility. Absorbance was reduced in ears with MEE compared to ears from the control group. Absorbance and admittance magnitude were the best single WATF predictors of MEE, but a predictor combining absorbance, admittance magnitude, and phase was the most accurate. Absorbance varied systematically with TM mobility based on data from pneumatic otoscopy. Results showed that absorbance is sensitive to middle-ear stiffness and MEE, and WATF predictions of MEE in young children are as accurate as those reported for methods recommended by the clinical guidelines. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

  1. Vestibular Function After Cochlear Implantation: A Comparison of Three Types of Electrodes.

    Science.gov (United States)

    Frodlund, Jonas; Harder, Henrik; Mäki-Torkko, Elina; Ledin, Torbjörn

    2016-12-01

    To investigate the vestibular function after cochlear implantation with different types of electrode arrays. Retrospective cohort study. Academic tertiary referral center. Forty three adults underwent first cochlear implantation. Three consecutive series of patients: Group 1 (n = 13) implanted with a precurved electrode, Group 2 (n = 15) implanted with a straight electrode, Group 3 (n = 15) implanted with a flexible electrode. Patient's vestibular functions were assessed with pre- and postoperative caloric testing using videonystagmography (VNG). The postoperative reduction of the maximum slow phase velocity (MSPV) in the implanted ear was evaluated. Medical charts were reviewed to evaluate the occurrence of late onset of postoperative vestibular symptoms. Mean reduction of MSPV was 7.6/s (standard deviation [SD] 8.0) in Group 1, 23.1/s (SD 16.6) in Group 2, and 0.1/s (SD 18.5) in Group 3. Significant difference was found between Group 1 and 2 (p < 0.030) and between Group 2 and 3 (p < 0.001). Group 2 showed a higher prevalence of late onset of clinical vertigo (28.6%) than Group 1 (7.7%) and 3 (6.7%). In this prospective study, significantly larger reductions of caloric responses were found in subjects implanted with a straight electrode compared with subjects implanted with a precurved or flexible electrode. These findings seem to correlate to a higher prevalence of postoperative vertigo.

  2. Cochlear impairment and autoimmune ear disorder in a patient with breast cancer

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    Alessandra Fioretti

    2017-03-01

    Full Text Available The purpose of this study was to consider the possible role of autoimmune diseases and paraneoplastic syndrome in the genesis of tinnitus. The incidence of autoimmune inner ear disease (AIED is rare, accounting for <1% of all cases of hearing impairment and dizziness. In presence of auditory and vestibular deficit in oncological patients, a paraneoplastic syndrome with cochleovestibulopathy should be considered. We described a 50-year-old Caucasian woman came to our attention with complaints of severe disabling bilateral tinnitus (Tinnitus Handicap Inventory, THI: 96, ear fullness and headache. The onset of tinnitus was associated to the last breast implant and prolonged antibiotic therapy. Serological autoimmunity tests were positive and a diagnosis of mixed connective tissue disease with notes of fibromyalgia was made. Pure tone audiometry testing revealed bilateral fluctuating mild hearing loss on high frequencies. The tinnitus was successfully treated with bilateral wideband sound generators (listening 8-9 hours for day regulated at the mixing point. At 12 months follow up THI has shrunk considerably (THI: 4 and the patient has continued treatment only with the sound pillow. In conclusion significant progress is needed to better understand the role of autoantibodies in the pathogenesis and diagnosis of paraneoplastic cochleovestibulopathy. To our knowledge, our study is the first in which hearing loss and tinnitus is considered as a manifestation of a paraneoplastic syndrome.

  3. The ear region of Latimeria chalumnae: functional and evolutionary implications.

    Science.gov (United States)

    Bernstein, Peter

    2003-01-01

    The anatomy of Latimeria chalumnae has figured prominently in discussions about tetrapod origins. While the gross anatomy of Latimeria is well documented, relatively little is known about its otic anatomy and ontogeny. To examine the inner ear and the otoccipital part of the cranium, a serial-sectioned juvenile coelacanth was studied in detail and a three-dimensional reconstruction was made. The ear of Latimeria shows a derived condition compared to other basal sarcopterygians in having a connection between left and right labyrinths. This canalis communicans is perilymphatic in nature and originates at the transition point of the saccule and the lagena deep in the inner ear, where a peculiar sense end organ can be found. In most gnathostomes the inner ears are clearly separated from each other. A connection occurs in some fishes, e.g. within the Ostariophysi. In the sarcopterygian lineage no connections between the inner ears are known except in the Actinistia. Some fossil actinistians show a posteriorly directed duct lying between the foramen magnum and the notochordal canal, similar to the condition in the ear of Latimeria, so this derived character complex probably developed early in actinistian history. Because some features of the inner ear of Latimeria have been described as having tetrapod affinities, the problem of hearing and the anatomy of the otical complex in the living coelacanth has been closely connected to the question of early tetrapod evolution. It was assumed in the past that the structure found in Latimeria could exemplify a transitional stage in otic evolution between the fishlike sarcopterygians and the first tetrapods in a functional or even phylogenetic way. Here the possibility is considered that the canalis communicans does not possess any auditory function but rather is involved in sensing pressure changes during movements involving the intracranial joint. Earlier hypotheses of a putative tympanic ear are refuted.

  4. Cochlear Impairment and Autoimmune Ear Disorder in a Patient with Breast Cancer.

    Science.gov (United States)

    Fioretti, Alessandra; Di Rubbo, Vittoria; Peri, Giorgia; Vitti, Elisa; Cisternino, Sara; Varakliotis, Theodoros; Eibenstein, Alberto

    2017-02-01

    The purpose of this study was to consider the possible role of autoimmune diseases and paraneoplastic syndrome in the genesis of tinnitus. The incidence of autoimmune inner ear disease (AIED) is rare, accounting for autoimmunity tests were positive and a diagnosis of mixed connective tissue disease with notes of fibromyalgia was made . Pure tone audiometry testing revealed bilateral fluctuating mild hearing loss on high frequencies. The tinnitus was successfully treated with bilateral wideband sound generators (listening 8-9 h for day) regulated at the mixing point. At 12 months follow up THI has shrunk considerably (THI: 4) and the patient has continued treatment only with the sound pillow. In conclusion significant progress is needed to better understand the role of autoantibodies in the pathogenesis and diagnosis of paraneoplastic cochleovestibulopathy. To our knowledge, our study is the first in which hearing loss and tinnitus is considered as a manifestation of a paraneoplastic syndrome.

  5. Chronic Conductive Hearing Loss Leads to Cochlear Degeneration.

    Science.gov (United States)

    Liberman, M Charles; Liberman, Leslie D; Maison, Stéphane F

    2015-01-01

    Synapses between cochlear nerve terminals and hair cells are the most vulnerable elements in the inner ear in both noise-induced and age-related hearing loss, and this neuropathy is exacerbated in the absence of efferent feedback from the olivocochlear bundle. If age-related loss is dominated by a lifetime of exposure to environmental sounds, reduction of acoustic drive to the inner ear might improve cochlear preservation throughout life. To test this, we removed the tympanic membrane unilaterally in one group of young adult mice, removed the olivocochlear bundle in another group and compared their cochlear function and innervation to age-matched controls one year later. Results showed that tympanic membrane removal, and the associated threshold elevation, was counterproductive: cochlear efferent innervation was dramatically reduced, especially the lateral olivocochlear terminals to the inner hair cell area, and there was a corresponding reduction in the number of cochlear nerve synapses. This loss led to a decrease in the amplitude of the suprathreshold cochlear neural responses. Similar results were seen in two cases with conductive hearing loss due to chronic otitis media. Outer hair cell death was increased only in ears lacking medial olivocochlear innervation following olivocochlear bundle cuts. Results suggest the novel ideas that 1) the olivocochlear efferent pathway has a dramatic use-dependent plasticity even in the adult ear and 2) a component of the lingering auditory processing disorder seen in humans after persistent middle-ear infections is cochlear in origin.

  6. The Human Cochlear Mechanical Nonlinearity Inferred via Psychometric Functions

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    Nizami Lance

    2013-12-01

    Extension of the model of Schairer and colleagues results in credible cochlear nonlinearities in man, suggesting that forward-masking provides a non-invasive way to infer the human mechanical cochlear nonlinearity.

  7. Across-site patterns of electrically evoked compound action potential amplitude-growth functions in multichannel cochlear implant recipients and the effects of the interphase gap.

    Science.gov (United States)

    Schvartz-Leyzac, Kara C; Pfingst, Bryan E

    2016-11-01

    Electrically evoked compound action potential (ECAP) measures of peak amplitude, and amplitude-growth function (AGF) slope have been shown to reflect characteristics of cochlear health (primarily spiral ganglion density) in anesthetized cochlear-implanted guinea pigs. Likewise, the effect of increasing the interphase gap (IPG) in each of these measures also reflects SGN density in the implanted guinea pig. Based on these findings, we hypothesize that suprathreshold ECAP measures, and also how they change as the IPG is increased, have the potential to be clinically applicable in human subjects. However, further work is first needed in order to determine the characteristics of these measures in humans who use cochlear implants. The current study examined across-site patterns of suprathreshold ECAP measures in 10 bilaterally-implanted, adult cochlear implant users. Results showed that both peak amplitude and slope of the AGF varied significantly from electrode to electrode in ear-specific patterns across the subjects' electrode arrays. As expected, increasing the IPG on average increased the peak amplitude and slope. Across ears, there was a significant, negative correlation between the slope of the ECAP AGF and the duration of hearing loss. Across-site patterns of ECAP peak amplitude and AGF slopes were also compared with common ground impedance values and significant correlations were observed in some cases, depending on the subject and condition. The results of this study, coupled with previous studies in animals, suggest that it is feasible to measure the change in suprathreshold ECAP measures as the IPG increases on most electrodes. Further work is needed to investigate the relationship between these measures and cochlear implant outcomes, and determine how these measures might be used when programming a cochlear-implant processor. Published by Elsevier B.V.

  8. Alteration of distortion product otoacoustic emission input/output functions in subjects with a previous history of middle ear dysfunction.

    Science.gov (United States)

    De P Campos, Ualace; Sanches, Seisse G; Hatzopoulos, Stavros; Carvallo, Renata M M; Kochanek, Krzysztof; Skarżyński, Henryk

    2012-04-01

    The aim of this study was to investigate the effects of sub-clinical alterations on the amplitudes and slopes of the DPOAE input-output responses from subjects with previous history of middle ear dysfunction. The study included 15 subjects with and 15 subjects without a history of otitis media in the last 10 years. All participants were assessed with acoustic immittance, pure-tone audiometry, and DPOAEs. For the later, I/O functions and I/O slopes were estimated at 1501, 2002, 3174, 4004 and 6384 Hz. No statistically significant differences were found between the 2 groups in terms of behavioral thresholds. The group with a previous history of middle ear dysfunction presented significantly lower mean DPOAE amplitudes at 2002, 3174 and 4004 Hz. In terms of DPOAE slopes, no statistically significant differences were observed at the tested frequencies, except at 3174 Hz. Middle ear pathologies can produce subclinical alterations that are undetectable with traditional pure-tone audiometry. The data from the present study show that reduced amplitude DPOAEs are associated with a previous history of middle ear complications. The corresponding DPOAE slopes were affected at only 1 tested frequency, suggesting that the cochlear non-linearity is preserved. Considering these results, it remains to be elucidated to what degree the DPOAE amplitude attenuation interferes with higher-order auditory tasks.

  9. Mouse Models for Pendrin-Associated Loss of Cochlear and Vestibular Function

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    Philine Wangemann

    2013-12-01

    Full Text Available The human gene SLC26A4 and the mouse ortholog Slc26a4 code for the protein pendrin, which is an anion exchanger expressed in apical membranes of selected epithelia. In the inner ear, pendrin is expressed in the cochlea, the vestibular labyrinth and the endolymphatic sac. Loss-of-function and hypo-functional mutations cause an enlargement of the vestibular aqueduct (EVA and sensorineural hearing loss. The relatively high prevalence of SLC26A4 mutations provides a strong imperative to develop rational interventions that delay, ameliorate or prevent pendrin-associated loss of cochlear and vestibular function. This review summarizes recent studies in mouse models that have been developed to delineate the role of pendrin in the physiology of hearing and balance and that have brought forward the concept that a temporally and spatially limited therapy may be sufficient to secure a life-time of normal hearing in children bearing mutations of SLC26A4.

  10. Origin of inner ear hair cells: morphological and functional differentiation from ciliary cells into hair cells in zebrafish inner ear.

    Science.gov (United States)

    Tanimoto, Masashi; Ota, Yukiko; Inoue, Maya; Oda, Yoichi

    2011-03-09

    Auditory and vestibular functions in vertebrates depend on the transduction of sound vibration or head acceleration into electrical responses in inner ear hair cells. Mechanoelectrical transduction occurs at the tip of stereocilia, which are polarized to form an orientational arrangement that determines directional sensitivity. It remains to be clarified when and how premature hair cells acquire their specialized structure and function in living animals. The developmental origin of inner ear hair cells has been studied in vivo in zebrafish embryos. Tether cells, a small number of ciliated cells associated with an "ear stone" (or otolith) in the embryonic zebrafish inner ear, are believed to be precocious hair cells. However, whether or not tether cells acquire hair bundles and mechanosensitivity remains unknown. In the present study, we investigated the morphological and functional development of tether cells. Immunohistochemical examination revealed that stereocilia appeared on the tether cell apex in a polarized arrangement at 22 h postfertilization (hpf). Labeling with FM1-43, a marker of functional mechanotransduction channels, and the in vivo electrophysiological recording of mechanotransducer responses in the developing inner ear demonstrated that tether cells acquired direction-selective mechanosensitivity at 23 hpf. These results revealed that tether cells begin to function as hair cells within an hour after the appearance of a polarized array of stereociliary bundles. Thus, the ciliary cells morphologically and functionally differentiate into the first sensory hair cells in the inner ear of the zebrafish.

  11. Brazilian adaptation of the Functioning after Pediatric Cochlear Implantation (FAPCI: comparison between normal hearing and cochlear implanted children

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    Trissia M.F. Vassoler

    2015-04-01

    Full Text Available OBJECTIVE: Enabling development of the ability to communicate effectively is the principal objective of cochlear implantation (CI in children. However, objective and effective metrics of communication for cochlear-implanted Brazilian children are lacking . The Functioning after Pediatric Cochlear Implantation (FAPCI, a parent/caregiver reporting instrument developed in the United States, is the first communicative performance scale for evaluation of real-world verbal communicative performance of 2-5-year-old children with cochlear implants. The primary aim was to cross-culturally adapt and validate the Brazilian-Portuguese version of the FAPCI. The secondary aim was to conduct a trial of the adapted Brazilian-Portuguese FAPCI (FAPCI-BP in normal hearing (NH and CI children. METHODS: The American-English FAPCI was translated by a rigorous forward-backward process. The FAPCI-BP was then applied to the parents of children with NH (n = 131 and CI (n = 13, 2-9 years of age. Test-retest reliability was verified. RESULTS: The FAPCI-BP was confirmed to have excellent internal consistency (Cronbach's alpha > 0.90. The CI group had lower FAPCI scores (58.38 ± 22.6 than the NH group (100.38 ± 15.2; p < 0.001, Wilcoxon test. CONCLUSION: The present results indicate that the FAPCI-BP is a reliable instrument. It can be used to evaluate verbal communicative performance in children with and without CI. The FAPCI is currently the only psychometrically-validated instrument that allows such measures in cochlear-implanted children.

  12. Assessment of Cochlear Function during Cochlear Implantation by Extra- and Intracochlear Electrocochleography

    Science.gov (United States)

    Dalbert, Adrian; Pfiffner, Flurin; Hoesli, Marco; Koka, Kanthaiah; Veraguth, Dorothe; Roosli, Christof; Huber, Alexander

    2018-01-01

    Objective: The aims of this study were: (1) To investigate the correlation between electrophysiological changes during cochlear implantation and postoperative hearing loss, and (2) to detect the time points that electrophysiological changes occur during cochlear implantation. Material and Methods: Extra- and intracochlear electrocochleography (ECoG) were used to detect electrophysiological changes during cochlear implantation. Extracochlear ECoG recordings were conducted through a needle electrode placed on the promontory; for intracochlear ECoG recordings, the most apical contact of the cochlear implant (CI) electrode itself was used as the recording electrode. Tone bursts at 250, 500, 750, and 1000 Hz were used as low-frequency acoustic stimuli and clicks as high-frequency acoustic stimuli. Changes of extracochlear ECoG recordings after full insertion of the CI electrode were correlated with pure-tone audiometric findings 4 weeks after surgery. Results: Changes in extracochlear ECoG recordings correlated with postoperative hearing change (r = −0.44, p = 0.055, n = 20). Mean hearing loss in subjects without decrease or loss of extracochlear ECoG signals was 12 dB, compared to a mean hearing loss of 22 dB in subjects with a detectable decrease or a loss of ECoG signals (p = 0.0058, n = 51). In extracochlear ECoG recordings, a mean increase of the ECoG signal of 4.4 dB occurred after opening the cochlea. If a decrease of ECoG signals occurred during insertion of the CI electrode, the decrease was detectable during the second half of the insertion. Conclusion: ECoG recordings allow detection of electrophysiological changes in the cochlea during cochlear implantation. Decrease of extracochlear ECoG recordings during surgery has a significant correlation with hearing loss 4 weeks after surgery. Trauma to cochlear structures seems to occur during the final phase of the CI electrode insertion. Baseline recordings for extracochlear ECoG recordings should be conducted

  13. Perception of Music and Speech in Adolescents with Cochlear Implants – A Pilot Study on Effects of Intensive Musical Ear Training

    DEFF Research Database (Denmark)

    Petersen, Bjørn; Sørensen, Stine Derdau; Pedersen, Ellen Raben

    BACKGROUND Sparse information is available about the new generation of congenitally deaf children, who have grown up with the assistance of cochlear implants (CIs) and have now become teenagers. However, recent studies indicate that to keep pace with their normal hearing (NH) peers, supplementary...... measures of rehabilitation are important throughout adolescence. Music training may provide a beneficial method of strengthening not only music perception, but also linguistic skills, particularly prosody. The purpose of this study was to examine perception of music and speech and music engagement...... of adolescent CI users and the potential effects of an intensive musical ear training program. METHODS Eleven adolescent CI users participated in a short intensive training program involving music making activities and computer based listening exercises. Ten NH agemates formed a reference group, who followed...

  14. Reestablishing speech understanding through musical ear training after cochlear implantation: a study of the potential cortical plasticity in the brain

    DEFF Research Database (Denmark)

    Petersen, Bjørn; Mortensen, Malene V; Gjedde, Albert

    2009-01-01

    Cochlear implants (CIs) provide impressive speech perception for persons with severe hearing loss, but many CI recipients fail in perceiving speech prosody and music. Successful rehabilitation depends on cortical plasticity in the brain and postoperative measures. The present study evaluates...... and children with CIs....

  15. Sensory integration functions of children with cochlear implants.

    Science.gov (United States)

    Koester, AnjaLi Carrasco; Mailloux, Zoe; Coleman, Gina Geppert; Mori, Annie Baltazar; Paul, Steven M; Blanche, Erna; Muhs, Jill A; Lim, Deborah; Cermak, Sharon A

    2014-01-01

    OBJECTIVE. We investigated sensory integration (SI) function in children with cochlear implants (CIs). METHOD. We analyzed deidentified records from 49 children ages 7 mo to 83 mo with CIs. Records included Sensory Integration and Praxis Tests (SIPT), Sensory Processing Measure (SPM), Sensory Profile (SP), Developmental Profile 3 (DP-3), and Peabody Developmental Motor Scales (PDMS), with scores depending on participants' ages. We compared scores with normative population mean scores and with previously identified patterns of SI dysfunction. RESULTS. One-sample t tests revealed significant differences between children with CIs and the normative population on the majority of the SIPT items associated with the vestibular and proprioceptive bilateral integration and sequencing (VPBIS) pattern. Available scores for children with CIs on the SPM, SP, DP-3, and PDMS indicated generally typical ratings. CONCLUSION. SIPT scores in a sample of children with CIs reflected the VPBIS pattern of SI dysfunction, demonstrating the need for further examination of SI functions in children with CIs during occupational therapy assessment and intervention planning. Copyright © 2014 by the American Occupational Therapy Association, Inc.

  16. An Investigation of Spatial Hearing in Children with Normal Hearing and with Cochlear Implants and the Impact of Executive Function

    Science.gov (United States)

    Misurelli, Sara M.

    The ability to analyze an "auditory scene"---that is, to selectively attend to a target source while simultaneously segregating and ignoring distracting information---is one of the most important and complex skills utilized by normal hearing (NH) adults. The NH adult auditory system and brain work rather well to segregate auditory sources in adverse environments. However, for some children and individuals with hearing loss, selectively attending to one source in noisy environments can be extremely challenging. In a normal auditory system, information arriving at each ear is integrated, and thus these binaural cues aid in speech understanding in noise. A growing number of individuals who are deaf now receive cochlear implants (CIs), which supply hearing through electrical stimulation to the auditory nerve. In particular, bilateral cochlear implants (BICIs) are now becoming more prevalent, especially in children. However, because CI sound processing lacks both fine structure cues and coordination between stimulation at the two ears, binaural cues may either be absent or inconsistent. For children with NH and with BiCIs, this difficulty in segregating sources is of particular concern because their learning and development commonly occurs within the context of complex auditory environments. This dissertation intends to explore and understand the ability of children with NH and with BiCIs to function in everyday noisy environments. The goals of this work are to (1) Investigate source segregation abilities in children with NH and with BiCIs; (2) Examine the effect of target-interferer similarity and the benefits of source segregation for children with NH and with BiCIs; (3) Investigate measures of executive function that may predict performance in complex and realistic auditory tasks of source segregation for listeners with NH; and (4) Examine source segregation abilities in NH listeners, from school-age to adults.

  17. Finite element analysis of the middle ear transfer functions and related pathologies.

    Science.gov (United States)

    Zhao, Fei; Koike, Takuji; Wang, Jie; Sienz, Hans; Meredith, Rhys

    2009-10-01

    With developments in software and micro-measurement technology, a three-dimensional middle ear finite element (FE) model can now be more easily constructed to study sound transfer function. Many FE models of the middle ear have been constructed to date, and each has its own particular advantages and disadvantages. In this article, we review the latest developments and technologies in the field of the FE models of the middle ear, and the use of FE in the study of middle ear pathology. Proposals are made for future developments in the field of finite element analysis of middle ear transfer function.

  18. Forward and reverse transfer functions of the middle ear based on pressure and velocity DPOAEs with implications for differential hearing diagnosis.

    Science.gov (United States)

    Dalhoff, Ernst; Turcanu, Diana; Gummer, Anthony W

    2011-10-01

    Recently it was shown that distortion product otoacoustic emissions (DPOAEs) can be measured as vibration of the human tympanic membrane in vivo, and proposed to use these vibration DPOAEs to support a differential diagnosis of middle-ear and cochlear pathologies. Here, we investigate how the reverse transfer function (r-TF), defined as the ratio of DPOAE-velocity of the umbo to DPOAE-pressure in the ear canal, can be used to diagnose the state of the middle ear. Anaesthetized guinea pigs served as the experimental animal. Sound was delivered free-field and the vibration of the umbo measured with a laser Doppler vibrometer (LDV). Sound pressure was measured 2-3 mm from the tympanic membrane with a probe-tube microphone. The forward transfer function (f-TF) of umbo velocity relative to ear-canal pressure was obtained by stimulating with multi-tone pressure. The r-TF was assembled from DPOAE components generated in response to acoustic stimulation with two stimulus tones of frequencies f(1) and f(2); f(2)/f(1) was constant at 1.2. The r-TF was plotted as function of DPOAE frequencies; they ranged from 1.7 kHz to 23 kHz. The r-TF showed a characteristic shape with an anti-resonance around 8 kHz as its most salient feature. The data were interpreted with the aid of a middle-ear transmission-line model taken from the literature for the cat and adapted to the guinea pig. Parameters were estimated with a three-step fitting algorithm. Importantly, the r-TF is governed by only half of the 15 independent, free parameters of the model. The parameters estimated from the r-TF were used to estimate the other half of the parameters from the f-TF. The use of r-TF data - in addition to f-TF data - allowed robust estimates of the middle-ear parameters to be obtained. The results highlight the potential of using vibration DPOAEs for ascertaining the functionality of the middle ear and, therefore, for supporting a differential diagnosis of middle-ear and cochlear pathologies

  19. Comparative Auditory Neuroscience: Understanding the Evolution and Function of Ears.

    Science.gov (United States)

    Manley, Geoffrey A

    2017-02-01

    Comparative auditory studies make it possible both to understand the origins of modern ears and the factors underlying the similarities and differences in their performance. After all lineages of land vertebrates had independently evolved tympanic middle ears in the early Mesozoic era, the subsequent tens of millions of years led to the hearing organ of lizards, birds, and mammals becoming larger and their upper frequency limits higher. In extant species, lizard papillae remained relatively small (70 mm (made possible by coiling), as do their upper frequency limits (from 12 to >200 kHz). The auditory organs of the three amniote groups differ characteristically in their cellular structure, but their hearing sensitivity and frequency selectivity within their respective hearing ranges hardly differ. In the immediate primate ancestors of humans, the cochlea became larger and lowered its upper frequency limit. Modern humans show an unusual trend in frequency selectivity as a function of frequency. It is conceivable that the frequency selectivity patterns in humans were influenced in their evolution by the development of speech.

  20. Usher proteins in inner ear structure and function.

    Science.gov (United States)

    Ahmed, Zubair M; Frolenkov, Gregory I; Riazuddin, Saima

    2013-11-01

    Usher syndrome (USH) is a neurosensory disorder affecting both hearing and vision in humans. Linkage studies of families of USH patients, studies in animals, and characterization of purified proteins have provided insight into the molecular mechanisms of hearing. To date, 11 USH proteins have been identified, and evidence suggests that all of them are crucial for the function of the mechanosensory cells of the inner ear, the hair cells. Most USH proteins are localized to the stereocilia of the hair cells, where mechano-electrical transduction (MET) of sound-induced vibrations occurs. Therefore, elucidation of the functions of USH proteins in the stereocilia is a prerequisite to understanding the exact mechanisms of MET.

  1. Vestibular Dysfunctions in Cochlear Implant Patients; A Vestibular Evoked Myogenic Potential Study

    Directory of Open Access Journals (Sweden)

    Masoud Motasaddi Zarandy

    2011-12-01

    Full Text Available Background and Aim: Vestibular evoked myogenic potential in response to click or short tone burst stimuli have been used as a clinical test for distinguish saccule and inferior vestibular nerve diseases. Different studies show that cochlear implant could have inverse effects on vestibular structures. We aimed to investigate vestibular evoked myogenic potential in unilateral cochlear implanted individuals in compare to normal individuals.Methods: Thirty-three unilateral cochlear implanted patients (mean age 19.96 years and 30 normal hearing individuals (mean age 24-27 years as control group were enrolled in this cross- sectional study. Absolute latencies and amplitudes of myogenic potential responses were measured and compared in both groups.Results: Myogenic potential recorded in both ears of all controls were normal. No response could be recorded in 16 patients (48.48% from both ears. In three patients, responses were recorded in both ears though the amplitude of waves was reduced in implanted ear. Unilateral response could be recorded in 14 patients only in their non-implanted ear.Conclusion: Vestibular evoked myogenic potential test is a useful tool for assessing saccular function in cochlear implant patients. Damages of osseous spiral lamina and basilar membrane after cochlear implantation could result in dysfunctions of vestibular organs specially saccule. It seems that saccule could be easily damaged after cochlear implantation. This would cause absence or reduced amplitudes in myogenic potential.

  2. Dissecting the frog inner ear with Gaussian noise .2. Temperature dependence of inner ear function

    NARCIS (Netherlands)

    vanDijk, P; Wit, HP; Segenhout, JM

    1997-01-01

    The temperature dependence of the response of single primary auditory nerve fibers (n = 31) was investigated in the European edible frog, Rana esculenta (seven ears). Nerve fiber responses were analyzed with Wiener kernel analysis and polynomial correlation. The responses were described with a

  3. Assessment of auditory cortical function in cochlear implant patients using 15O PET

    International Nuclear Information System (INIS)

    Young, J.P.; O'Sullivan, B.T.; Gibson, W.P.; Sefton, A.E.; Mitchell, T.E.; Sanli, H.; Cervantes, R.; Withall, A.; Royal Prince Alfred Hospital, Sydney,

    1998-01-01

    Full text: Cochlear implantation has been an extraordinarily successful method of restoring hearing and the potential for full language development in pre-lingually and post-lingually deaf individuals (Gibson 1996). Post-lingually deaf patients, who develop their hearing loss later in life, respond best to cochlear implantation within the first few years of their deafness, but are less responsive to implantation after several years of deafness (Gibson 1996). In pre-lingually deaf children, cochlear implantation is most effect in allowing the full development language skills when performed within a critical period, in the first 8 years of life. These clinical observations suggest considerable neural plasticity of the human auditory cortex in acquiring and retaining language skills (Gibson 1996, Buchwald 1990). Currently, electrocochleography is used to determine the integrity of the auditory pathways to the auditory cortex. However, the functional integrity of the auditory cortex cannot be determined by this method. We have defined the extent of activation of the auditory cortex and auditory association cortex in 6 normal controls and 6 cochlear implant patients using 15 O PET functional brain imaging methods. Preliminary results have indicated the potential clinical utility of 15 O PET cortical mapping in the pre-surgical assessment and post-surgical follow up of cochlear implant patients. Copyright (1998) Australian Neuroscience Society

  4. Language and Psychosocial Functioning among Deaf Learners with and without Cochlear Implants

    Science.gov (United States)

    Marschark, Marc; Machmer, Elizabeth; Spencer, Linda J.; Borgna, Georgianna; Durkin, Andreana; Convertino, Carol

    2018-01-01

    Various studies have examined psychosocial functioning and language abilities among deaf children with and without cochlear implants (CIs). Few, however, have explored how relations among those abilities might change with age and setting. Most relevant studies also have failed to consider that psychosocial functioning among both CI users and…

  5. Comparative Auditory Neuroscience: Understanding the Evolution and Function of Ears

    OpenAIRE

    Manley, Geoffrey A.

    2016-01-01

    Comparative auditory studies make it possible both to understand the origins of modern ears and the factors underlying the similarities and differences in their performance. After all lineages of land vertebrates had independently evolved tympanic middle ears in the early Mesozoic era, the subsequent tens of millions of years led to the hearing organ of lizards, birds, and mammals becoming larger and their upper frequency limits higher. In extant species, lizard papillae remained relatively s...

  6. Pax3 function is required specifically for inner ear structures with melanogenic fates.

    Science.gov (United States)

    Kim, Hongkyung; Ankamreddy, Harinarayana; Lee, Dong Jin; Kong, Kyoung-Ah; Ko, Hyuk Wan; Kim, Myoung Hee; Bok, Jinwoong

    2014-03-14

    Pax3 mutations result in malformed inner ears in Splotch mutant mice and hearing loss in humans with Waardenburg's syndrome type I. In the inner ear, Pax3 is thought to be involved mainly in the development of neural crest. However, recent studies have shown that Pax3-expressing cells contribute extensively to multiple inner ear structures, some of which were considered to be derived from the otic epithelium. To examine the specific functions of Pax3 during inner ear development, fate mapping of Pax3 lineage was performed in the presence or absence of functional Pax3 proteins using Pax3(Cre) knock-in mice bred to Rosa26 reporter (R26R) line. β-gal-positive cells were widely distributed in Pax3(Cre/+); R26R inner ears at embryonic day (E) 15.5, including the endolymphatic duct, common crus, cristae, maculae, cochleovestibular ganglion, and stria vascularis. In the absence of Pax3 in Pax3(Cre/Cre); R26R inner ears, β-gal-positive cells disappeared from regions with melanocytes such as the stria vascularis of the cochlea and dark cells in the vestibule. Consistently, the expression of Dct, a melanoblast marker, was also absent in the mutant inner ears. However, when examined at E11.5, β-gal positive cells were present in Pax3(Cre/Cre) mutant otocysts, whereas Dct expression was absent, suggesting that Pax3 lineage with a melanogenic fate migrated to the inner ear, yet failed to differentiate and survive without Pax3 function. Gross inner ear morphology was generally normal in Pax3(Cre/Cre) mutants, unless neural tube defects extended to the cranial region. Taken together, these results suggest that despite the extensive contribution of Pax3-expressing cells to multiple inner ear tissues, Pax3 function is required specifically for inner ear components with melanogenic fates. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Assessment of morphological-functional state of children with cochlear implants

    Directory of Open Access Journals (Sweden)

    V.M. Pysanko

    2016-10-01

    Full Text Available Purpose: assessment of morphological-functional state of pre-school age children with cochlear implants and substantiation of need in post-operative rehabilitation in period of preparation for comprehensive school. Material: we tested weakly hearing children with cochlear implants (n=127, age - 5.6±0.6 years. They were the main group. Control group consisted of children with normal hearing (n=70, age - 5.7±0.4 years. Morphological-functional state was assessed by indicators of physical and biological condition, visual analyzer, posture parameters and foot arch, muscular system and level of coordination. We calculated index of integral morphological-functional state assessment. Results: Morphological functional state of most of children (with cochlear implants was characterized by low physical condition indicators and disharmony. We observed delay in biological development. Index of morphological-functional state integral assessment witnesses, that such child can not study in comprehensive school. Rehabilitation program can reduce the gap between children with normal hearing and those with cochlear implants. Conclusions: Rehabilitation program facilitates quicker domestic and social rehabilitation of children at the account of widening the circle of communication, learning new actions and conceptions. It can permit for such children to study at school together with their healthy peers.

  8. Occurrence of NaK-ATPase isoforms during rat inner ear development and functional implications.

    NARCIS (Netherlands)

    Peters, T.A.; Kuijpers, W.; Curfs, J.H.A.J.

    2001-01-01

    This study examined the presence of NaK-ATPase isoforms in the developing inner ear of the rat and studied the importance of functional subunit combinations in endolymph homeostasis. The findings were: (a) the combination alpha 1 beta 1 is found in epithelial, mesenchymal, and neural inner ear cells

  9. Verbal Processing Speed and Executive Functioning in Long-Term Cochlear Implant Users

    Science.gov (United States)

    AuBuchon, Angela M.; Pisoni, David B.; Kronenberger, William G.

    2015-01-01

    Purpose: The purpose of this study was to report how "verbal rehearsal speed" (VRS), a form of covert speech used to maintain verbal information in working memory, and another verbal processing speed measure, perceptual encoding speed, are related to 3 domains of executive function (EF) at risk in cochlear implant (CI) users: verbal…

  10. Neurod1 regulates survival and formation of connections in mouse ear and brain.

    Science.gov (United States)

    Jahan, Israt; Kersigo, Jennifer; Pan, Ning; Fritzsch, Bernd

    2010-07-01

    The developing sensory neurons of the mammalian ear require two sequentially activated bHLH genes, Neurog1 and Neurod1, for their development. Neurons never develop in Neurog1 null mice, and most neurons die in Neurod1 null mutants, a gene upregulated by Neurog1. The surviving neurons of Neurod1 null mice are incompletely characterized in postnatal mice because of the early lethality of mutants and the possible compromising effect of the absence of insulin on peripheral neuropathies. Using Tg(Pax2-cre), we have generated a conditional deletion of floxed Neurod1 for the ear; this mouse is viable and allows us to investigate ear innervation defects of Neurod1 absence only in the ear. We have compared the defects in embryos and show an ear phenotype in conditional Neurod1 null mice comparable with the systemic Neurod1 null mouse. By studying postnatal animals, we show that Neurod1 not only is necessary for the survival of most spiral and many vestibular neurons, but is also essential for a segregated central projection of vestibular and cochlear afferents. In the absence of Neurod1 in the ear, vestibular and cochlear afferents enter the cochlear nucleus as a single mixed nerve. Neurites coming from vestibular and cochlear sensory epithelia project centrally to both cochlear and vestibular nuclei, in addition to their designated target projections. The peripheral innervation of the remaining sensory neurons is disorganized and shows collaterals of single neurons projecting to multiple endorgans, displaying no tonotopic organization of the organ of Corti or the cochlear nucleus. Pending elucidation of the molecular details for these Neurod1 functions, these data demonstrate that Neurod1 is not only a major factor for the survival of neurons but is crucial for the development of normal ear connections, both in the ear and in the central nervous system.

  11. Correlation between middle-ear pressure-regulation functions and outcome of type-I tympanoplasty.

    Science.gov (United States)

    Takahashi, Haruo; Sato, Hiroaki; Nakamura, Hajime; Naito, Yasushi; Umeki, Hiroshi

    2007-06-01

    To examine the correlation between the middle-ear pressure-regulation functions including active eustachian tube (ET) functions and transmucosal gas exchange function, and outcome of tympanoplasty. Seventy five patients (78 ears) with non-cholesteatomatous chronic otitis media with eardrum perforation but without ossicular damage or middle-ear anomaly participated in this study. Before surgery, patency of the ET was examined by applying positive pressure to the middle ear through the eardrum perforation, and then the ET pressure-regulation functions were examined using the inflation-deflation test. Also their transmucosal gas exchange function was evaluated by examining the presence or absence of aeration in the mastoid on the CT before surgery or through the microscope during the surgery. All of them underwent type-I tympanoplasty, and their postoperative conditions including the hearing were followed for more than 6 months. The outcome of the surgery was judged as poor outcome when they had any of the following conditions; more than 20 dB of mean air-bone gap, spontaneous perforation within 6 months, or persistent wet condition including recurrent otorrhea. First, the outcome of all the four ears of which ETs were considered mechanically obstructed was poor. Next, among the remaining 74 ears, none of the three individual parameters, including positive and negative middle-ear pressure-equalizing functions and mastoid aeration, showed significantly positive correlation with the outcome of the surgery, but significantly higher incidence of poor outcome was seen only when all the three parameters were poor. These results indicated that impairment of all the middle-ear pressure-regulation functions was likely to cause poor outcome of tympanoplasty, and also allowed us reconfirm that ears with mechanically obstructed ETs were contraindicated for tympanoplasty. Therefore, assessment of mastoid condition is important as well as the ET function before tympanoplasty.

  12. Change in cochlear response in an animal model of otitis media with effusion.

    Science.gov (United States)

    Dai, Chenkai; Gan, Rong Z

    2010-01-01

    Our previous studies confirm that middle ear mobility is reduced in the presence of otitis media with effusion (OME). Variations in middle ear function may result in changes in cochlear response in OME ears. With the long-term goal of evaluating cochlear function in OME ears, the aim of this study was to measure the displacement of the basilar membrane (BM) in guinea pig ears with OME. Vibrations of the BM at the apex and basal turn were measured in an in vitro preparation extracted 3 and 14 days after injection of lipopolysaccharide in the middle ear of guinea pigs. The results show that the displacement sensitivity of the BM at the apex and the basal turn to sound pressure in the ear canal was reduced up to 25 dB at their characteristic frequencies, respectively. Cochlear gain with respect to umbo movement was also changed in ears with OME in both groups. This study provides data for analysis of the change of BM vibration in a guinea pig OME model. 2009 S. Karger AG, Basel.

  13. Does systemic steroid deficiency affect inner ear functions?

    Science.gov (United States)

    Dogan, Remzi; Merıc, Ayşenur; Gedık, Ozge; Tugrul, Selahattin; Eren, Sabri Baki; Ozturan, Orhan

    2015-01-01

    Today corticosteroids are employed for the treatment of various inner ear disorders. In this study we have investigated probable changes in hearing functions resulting from a deficiency of systemic steroid secretions. Twenty four healthy female rats were used in our study, allocated into three groups (medical adrenalectomy, medical adrenalectomy+dexamethasone, no treatment). Audiological evaluations were conducted at the beginning of the study and on days 7, 14 and 21. Blood samples were taken at the beginning and at the end of the study and blood corticosterone levels were determined. While there were no significant differences between the basal, 7th, 14th and 21st day DPOAE values of group 1, their ABR threshold values showed significant increases. In group 2, there were no significant differences between the basal, 7th, 14th and 21st day DPOAE values. ABR thresholds of group 2 showed significant increases on days 7 and 14 as compared to their basal values, but there were no significant differences between the 21st day and basal ABR threshold values. There were no significant differences between the basal cortisol levels of the three groups. The mean cortisol level of group 1 on day 21 was found to be significantly lower than those of groups 2 and 3. The results of the study demonstrated that there were no significant changes in DPOAE values with the cessation of cortisol secretion, while there was a progressive increase in ABR thresholds, which could be overcome with cortisone replacement. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Neuroradiological imaging in patients with sensorineural hearing loss prior to cochlear implantation; Neuroradiologische Diagnostik bei Patienten mit sensorineuralem Hoerverlust vor Cochlea-Implantation

    Energy Technology Data Exchange (ETDEWEB)

    Biller, A.; Bartsch, A.; Solymosi, L.; Bendszus, M. [Abteilung fuer Neuroradiologie, Universitaet Wuerzburg (Germany); Knaus, C.; Mueller, J. [Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenkranke, Universitaet Wuerzburg (Germany)

    2007-09-15

    Cochlear implantation (CI) is an established technique for enabling speech perception in patients suffering from severe bilateral sensorineural hearing loss (SNHL). Thorough preoperative radiological assessment is essential for correctly evaluating the indication for surgery and safely performing cochlear implantation. CT and conventional and functional MRI are available for radiological assessment. Therefore, knowledge of the most frequent congenital syndromal, non-syndromal, and acquired malformations of inner ear structures is fundamental. This article provides information about imaging techniques prior to CI and relevant malformations of the inner ear. Safety aspects for patients with a cochlear implant undergoing MR imaging are also discussed. (orig.)

  15. Endoscopic cochlear implantation: Call for caution.

    Science.gov (United States)

    Tarabichi, Muaaz; Nazhat, Omar; Kassouma, Jamal; Najmi, Murtaza

    2016-03-01

    To assess whether transcanal endoscopic access to the basal turn of the cochlea for cochlear implantation is appropriate. Case series study. We reviewed 100 consecutive computed tomographic studies of the sinuses and temporal bone in our institution. We excluded studies that demonstrated evidence of congenital anomalies, chronic ear disease, or inadequate visualization of the cochlea. On axial sections, the angles of the basal turn of the cochlea and of the ear canal in reference to the sagittal plane were recorded as a function of age. Eighty-four studies were included and 16 were excluded. There was significant variability in the relationship between the ear canal and the basal turn of the cochlea in reference to the sagittal plane. A clear majority of images demonstrated the basal turn of the cochlea to align with a more posterior angle than that of the ear canal. The trajectory provided by posterior tympanotomy aligns more favorably with the basal turn of the cochlea than transcanal access. Endoscopic technique, primarily an ear canal intervention, may not be useful in cochlear implant surgery. 4. Laryngoscope, 126:689-692, 2016. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  16. Induction of Functional Hair-Cell-Like Cells from Mouse Cochlear Multipotent Cells

    Directory of Open Access Journals (Sweden)

    Quanwen Liu

    2016-01-01

    Full Text Available In this paper, we developed a two-step-induction method of generating functional hair cells from inner ear multipotent cells. Multipotent cells from the inner ear were established and induced initially into progenitor cells committed to the inner ear cell lineage on the poly-L-lysine substratum. Subsequently, the committed progenitor cells were cultured on the mitotically inactivated chicken utricle stromal cells and induced into hair-cell-like cells containing characteristic stereocilia bundles. The hair-cell-like cells exhibited rapid permeation of FM1-43FX. The whole-cell patch-clamp technique was used to measure the membrane currents of cells differentiated for 7 days on chicken utricle stromal cells and analyze the biophysical properties of the hair-cell-like cells by recording membrane properties of cells. The results suggested that the hair-cell-like cells derived from inner ear multipotent cells were functional following differentiation in an enabling environment.

  17. Functions of the inner ear in psoriatic arthritis.

    Science.gov (United States)

    Gunes, Akif; Gundogdu, Ibrahim; Mutlu, Murad; Ozturk, Erhan Arif; Cakci, Aytul; Akin, Istemihan

    2016-12-01

    This study aimed to investigate whether there is a negative impact as a result of psoriatic arthritis disease of the inner ear function. Twenty-four successive patients and 38 healthy volunteers, younger than 60 years of age, who were followed up for at least for one year in the outpatient clinics of physical therapy and rehabilitation with the diagnosis of PsA according to CASPAR criteria (17) and who did not complain of any hearing impairment were included in the study. Distortion-product otoacoustic emission (DPOAE) values between 1kHz and 4kHz, tympanometric examination results, stapes reflex values, speech reception threshold (SRT) and speech discrimination (SD) values, pure-tone values between 250 and 8000Hz and high-frequency values between 10,000, 12,500 and 16,000Hz were analyzed. Statistical comparisons between both groups were performed using chi-square test and Mann-Whitney U test. p<0.05 was accepted as the level of statistical significance. Our study population consisted of 24 [9 male (37.5%) and 15 female (62.5%)] patients with a mean age of 47.21±11.28 (range, 28-59) years and 38 [16 male (42.1%) and 22 female (57.9%)] healthy volunteers with a mean age of 44.39±8.12 (range, 29-59) years as the control group. Mean duration of arthritis was 7.62±4.88 years. In the evaluation of hearing frequencies of the patients between 4000 and 6000Hz, a statistically significant difference was found relative to the control group (p<005). DPOAE values of the patients were analyzed within the 1000-4000Hz interval. When compared with the control group, a statistically significant difference was found at 3000 and 4000Hz (p<005). Our study provides strong evidence suggesting the necessity of monitorization of these patients regarding sensorineural hearing loss so as to take measures against the development of hearing loss during early stage, which may be another disability in patients with PsA, which is itself a potential cause of severe disability. Copyright

  18. CT evaluation of preoperative cochlear implantation cochlear implantation

    International Nuclear Information System (INIS)

    Tan Xiuzhong; Zhong Lansheng; Lan Bowen; Huang Yaosheng; Du Baowen; Zhu Jian

    2004-01-01

    Objective: To evaluate CT scan as a preoperative evaluation for cochlear implantation candidates. Methods: Axial high-resolution temporal bone CT and three-dimensional reconstruction of inner ear were performed in 93 patients with sensorineural hearing loss. results: Among 81 patients with congenital sensorineural deafness, Mondini malformation was seen in 7 case (13 ears); large vestibular aqueduct syndrome (LVAS) was revealed in 5 cases (8 ears); and inner ear ossification was found in 1 case (2 ears). In 1 case (2 ears) of inner ear fibrosis, reduced cochlear signal was noted on MRI but no unremarkable findings was shown on CT scan, however, in the operation, the device could not inserted into the basal circle of the cochlea, due to fibrous obliteration. In 12 patients with post-speech deafness, chronic suppurative tympanitis was seen in 2 cases (4 ears), and inner ear ossification was revealed in 1 case (2 ears). Conclusion: CT plays an indispensable role in the pre-operative evaluation of cochlear implantation. T 2 -weighted FSE-MRI of the inner ear is a useful complementary to CT scan. (authors)

  19. Ear Infection (Middle Ear)

    Science.gov (United States)

    ... back of the nose believed to play a role in immune system activity. This function may make them particularly vulnerable to infection, inflammation and swelling. Because adenoids are near the ... likely to play a role in ear infections in children because children have ...

  20. Functional near-infrared spectroscopy for neuroimaging in cochlear implant recipients

    Science.gov (United States)

    Saliba, Joe; Bortfeld, Heather; Levitin, Daniel J.; Oghalai, John S.

    2016-01-01

    Functional neuroimaging can provide insight into the neurobiological factors that contribute to the variations in individual hearing outcomes following cochlear implantation. To date, measuring neural activity within the auditory cortex of cochlear implant (CI) recipients has been challenging, primarily because the use of traditional neuroimaging techniques is limited in people with CIs. Functional near-infrared spectroscopy (fNIRS) is an emerging technology that offers benefits in this population because it is non-invasive, compatible with CI devices, and not subject to electrical artifacts. However, there are important considerations to be made when using fNIRS to maximize the signal to noise ratio and to best identify meaningful cortical responses. This review considers these issues, the current data, and future directions for using fNIRS as a clinical application in individuals with CIs. PMID:26883143

  1. Cochlear implantation in Mondini dysplasia.

    Science.gov (United States)

    Daneshi, Ahmad; Hassanzadeh, Saeid; Abasalipour, Parvaneh; Emamdjomeh, Hessamaddin; Farhadi, Mohammad

    2003-01-01

    The use of cochlear implantation to treat patients with inner ear malformations such as Mondini dysplasia has been increasingly successful. Until now, conventional hearing aids in these patients have not performed well. Consequently, the hearing problem for patients with this condition has been somewhat improved with the use of cochlear implants. Various results of cochlear implantation have been reported in these patients so far. This is a report of 5 patients with Mondini malformation who have undergone cochlear implant surgery. Copyright 2003 S. Karger AG, Basel

  2. Hyperbaric oxygen upregulates cochlear constitutive nitric oxide synthase

    Directory of Open Access Journals (Sweden)

    Kao Ming-Ching

    2011-02-01

    Full Text Available Abstract Background Hyperbaric oxygen therapy (HBOT is a known adjuvant for treating ischemia-related inner ear diseases. Controversies still exist in the role of HBOT in cochlear diseases. Few studies to date have investigated the cellular changes that occur in inner ears after HBOT. Nitric oxide, which is synthesized by nitric oxide synthase (NOS, is an important signaling molecule in cochlear physiology and pathology. Here we investigated the effects of hyperbaric oxygen on eardrum morphology, cochlear function and expression of NOS isoforms in cochlear substructures after repetitive HBOT in guinea pigs. Results Minor changes in the eardrum were observed after repetitive HBOT, which did not result in a significant hearing threshold shift by tone burst auditory brainstem responses. A differential effect of HBOT on the expression of NOS isoforms was identified. Upregulation of constitutive NOS (nNOS and eNOS was found in the substructures of the cochlea after HBOT, but inducible NOS was not found in normal or HBOT animals, as shown by immunohistochemistry. There was no obvious DNA fragmentation present in this HBOT animal model. Conclusions The present evidence indicates that the customary HBOT protocol may increase constitutive NOS expression but such upregulation did not cause cell death in the treated cochlea. The cochlear morphology and auditory function are consequently not changed through the protocol.

  3. A genome-wide linkage and association study of musical aptitude identifies loci containing genes related to inner ear development and neurocognitive functions

    Science.gov (United States)

    Oikkonen, J.; Huang, Y.; Onkamo, P.; Ukkola-Vuoti, L.; Raijas, P.; Karma, K.; Vieland, V. J.; Järvelä, I.

    2014-01-01

    Humans have developed the perception, production and processing of sounds into the art of music. A genetic contribution to these skills of musical aptitude has long been suggested. We performed a genome-wide scan in 76 pedigrees (767 individuals) characterized for the ability to discriminate pitch (SP), duration (ST) and sound patterns (KMT), which are primary capacities for music perception. Using the Bayesian linkage and association approach implemented in program package KELVIN, especially designed for complex pedigrees, several SNPs near genes affecting the functions of the auditory pathway and neurocognitive processes were identified. The strongest association was found at 3q21.3 (rs9854612) with combined SP, ST and KMT test scores (COMB). This region is located a few dozen kilobases upstream of the GATA binding protein 2 (GATA2) gene. GATA2 regulates the development of cochlear hair cells and the inferior colliculus (IC), which are important in tonotopic mapping. The highest probability of linkage was obtained for phenotype SP at 4p14, located next to the region harboring the protocadherin 7 gene, PCDH7. Two SNPs rs13146789 and rs13109270 of PCDH7 showed strong association. PCDH7 has been suggested to play a role in cochlear and amygdaloid complexes. Functional class analysis showed that inner ear and schizophrenia related genes were enriched inside the linked regions. This study is the first to show the importance of auditory pathway genes in musical aptitude. PMID:24614497

  4. A genome-wide linkage and association study of musical aptitude identifies loci containing genes related to inner ear development and neurocognitive functions.

    Science.gov (United States)

    Oikkonen, J; Huang, Y; Onkamo, P; Ukkola-Vuoti, L; Raijas, P; Karma, K; Vieland, V J; Järvelä, I

    2015-02-01

    Humans have developed the perception, production and processing of sounds into the art of music. A genetic contribution to these skills of musical aptitude has long been suggested. We performed a genome-wide scan in 76 pedigrees (767 individuals) characterized for the ability to discriminate pitch (SP), duration (ST) and sound patterns (KMT), which are primary capacities for music perception. Using the Bayesian linkage and association approach implemented in program package KELVIN, especially designed for complex pedigrees, several single nucleotide polymorphisms (SNPs) near genes affecting the functions of the auditory pathway and neurocognitive processes were identified. The strongest association was found at 3q21.3 (rs9854612) with combined SP, ST and KMT test scores (COMB). This region is located a few dozen kilobases upstream of the GATA binding protein 2 (GATA2) gene. GATA2 regulates the development of cochlear hair cells and the inferior colliculus (IC), which are important in tonotopic mapping. The highest probability of linkage was obtained for phenotype SP at 4p14, located next to the region harboring the protocadherin 7 gene, PCDH7. Two SNPs rs13146789 and rs13109270 of PCDH7 showed strong association. PCDH7 has been suggested to play a role in cochlear and amygdaloid complexes. Functional class analysis showed that inner ear and schizophrenia-related genes were enriched inside the linked regions. This study is the first to show the importance of auditory pathway genes in musical aptitude.

  5. Prenatal and postnatal serum PCB concentrations and cochlear function in children at 45 months of age.

    Science.gov (United States)

    Jusko, Todd A; Sisto, Renata; Iosif, Ana-Maria; Moleti, Arturo; Wimmerová, Sonˇa; Lancz, Kinga; Tihányi, Juraj; Sovčiková, Eva; Drobná, Beata; Palkovičová, L'ubica; Jurečková, Dana; Thevenet-Morrison, Kelly; Verner, Marc-André; Sonneborn, Dean; Hertz-Picciotto, Irva; Trnovec, Tomáš

    2014-11-01

    Some experimental and human data suggest that exposure to polychlorinated biphenyls (PCBs) may induce ototoxicity, though results of previous epidemiologic studies are mixed and generally focus on either prenatal or postnatal PCB concentrations exclusively. Our aim was to evaluate the association between pre- and postnatal PCB concentrations in relation to cochlear status, assessed by distortion product otoacoustic emissions (DPOAEs), and to further clarify the critical periods in development where cochlear status may be most susceptible to PCBs. A total of 351 children from a birth cohort in eastern Slovakia underwent otoacoustic testing at 45 months of age. Maternal pregnancy, cord, and child 6-, 16-, and 45-month blood samples were collected and analyzed for PCB concentrations. At 45 months of age, DPOAEs were assessed at 11 frequencies in both ears. Multivariate, generalized linear models were used to estimate the associations between PCB concentrations at different ages and DPOAEs, adjusting for potential confounders. Maternal and cord PCB-153 concentrations were not associated with DPOAEs at 45 months. Higher postnatal PCB concentrations at 6-, 16-, and 45-months of age were associated with lower (poorer) DPOAE amplitudes. When all postnatal PCB exposures were considered as an area-under-the-curve metric, an increase in PCB-153 concentration from the 25th to the 75th percentile was associated with a 1.6-dB SPL (sound pressure level) decrease in DPOAE amplitude (95% CI: -2.6, -0.5; p = 0.003). In this study, postnatal rather than maternal or cord PCB concentrations were associated with poorer performance on otoacoustic tests at age 45 months.

  6. The relationship of theory of mind and executive functions in normal, deaf and cochlear-implanted children

    Directory of Open Access Journals (Sweden)

    Farideh Nazarzadeh

    2014-08-01

    Full Text Available Background and Aim : Theory of mind refers to the ability to understand the others have mental states that can be different from one's own mental states or facts. This study aimed to investigate the relationship of theory of mind and executive functions in normal hearing, deaf, and cochlear-implanted children.Methods: The study population consisted of normal, deaf and cochlear-implanted girl students in Mashhad city, Iran. Using random sampling, 30 children (10 normal, 10 deaf and 10 cochlear-implanted in age groups of 8-12 years old were selected. To measure the theoty of mind, theory of mind 38-item scale and to assess executive function, Coolidge neuropsychological and personality test was used. Research data were analyzed using the Spearman correlation coefficient, analysis of variance and Kruskal-Wallis tests.Results: There was a significant difference between the groups in the theory of mind and executive function subscales, organization, planning-decision-making, and inhibition. Between normal and deaf groups (p=0.01, as well as cochlear-implanted and deaf groups (p=0.01, there was significant difference in planning decision-making subscale. There was not any significant relationship between the theory of mind and executive functions generally or the theory of mind and executive function subscales in these three groups independently.Conclusion: Based on our findings, cochlear-implanted and deaf children have lower performance in theory of mind and executive function compared with normal hearing children.

  7. In vivo visualized endolymphatic hydrops and inner ear functions in patients with electrocochleographically confirmed Ménière's disease.

    Science.gov (United States)

    Gürkov, Robert; Flatz, Wilhelm; Louza, Julia; Strupp, Michael; Ertl-Wagner, Birgit; Krause, Eike

    2012-08-01

    To study the correlation between the degree of endolymphatic hydrops as detected in vivo by magnetic resonance (MR) imaging and the auditory and vestibular function in patients with definite Ménière's disease. Prospective observational study. Tertiary referral center for balance disorders. In this prospective study, 41 patients who fulfilled the criteria for definite unilateral Ménière's disease according to the American Association of Otolaryngology-Head and Neck Surgery and who showed a summating potential-to-action potential ratio of greater than 0.4 on electrocochleography were included. Intratympanic contrast-enhanced 3 Tesla MR imaging of the inner ear was performed using a 3D Inversion Recovery Turbo Spin Echo sequence. The degree of endolymphatic hydrops was graded on a Likert scale (0-3) in the cochlea and by vestibular endolymph space ratio in the vestibulum. The degree of hydrops was then analyzed with respect to its correlation with audiometric hearing levels, interaural amplitude ratios of vestibular evoked myogenic potentials, degree of horizontal semicircular canal paresis on caloric irrigation, and disease duration. The degree of hearing loss and the disease duration correlated significantly with cochlear hydrops (r = 0.85; r = 0.34). Sacculus dysfunction was significantly correlated with vestibular hydrops (r = -0.47). There was no significant correlation between horizontal semicircular canal paresis and vestibular hydrops. In patients with clinically and electrocochleographically confirmed definite Ménière's disease, the degree of MR morphological hydrops severity correlates significantly with impairment of hearing function and sacculus function.

  8. A 3D-printed functioning anatomical human middle ear model.

    Science.gov (United States)

    Kuru, Ismail; Maier, Hannes; Müller, Mathias; Lenarz, Thomas; Lueth, Tim C

    2016-10-01

    The middle ear is a sophisticated and complex structure with a variety of functions, yet a delicate organ prone to injuries due to various reasons. Both, understanding and reconstructing its functions has always been an important topic for researchers from medical and technical background. Currently, human temporal bones are generally used as model for tests, experiments and validation of the numerical results. However, fresh human preparations are not always easily accessible and their mechanical properties vary with time and between individuals. Therefore we have built an anatomically based and functional middle ear model to serve as a reproducible test environment. Our middle ear model was manufactured with the aid of 3D-printing technology. We have segmented the essential functional elements from micro computed tomography data (μCT) of a single temporal bone. The ossicles were 3D-printed by selective laser melting (SLM) and the soft tissues were casted with silicone rubber into 3D-printed molds. The ear canal, the tympanic cavity and the inner ear were artificially designed, but their design ensured the anatomically correct position of the tympanic membrane, ossicular ligaments and the oval window. For the determination of their auditory properties we have conducted two kinds of tests: measurement of the stapes footplate response to sound and tympanometry of the model. Our experiments regarding the sound transmission showed that the model has a similar behavior to a human middle ear. The transfer function has a resonance frequency at around 1 kHz, the stapes' response is almost constant for frequencies below the resonance and a roll-off is observed above the resonance. The tympanometry results show that the compliance of the middle ear model is similar to the compliance of a healthy human middle ear. We also present that we were able to manipulate the transmission behavior, so that healthy or pathological scenarios can be created. For this purpose we have

  9. Development, function and test of a static test bench for UHF-RFID ear tags

    Directory of Open Access Journals (Sweden)

    Felix Adrion

    2015-05-01

    Full Text Available Ultra-high-frequency radio frequency identification systems (UHF-RFID systems offer multiple application possibilities for animal identification. In a present joint project, UHF transponder ear tags and readers are currently being developed especially for use with cattle and pigs. An automatic test bench was developed for measuring the detection area and signal strength of various transponders, the aim being to enable with this test bench comparison of different types of UHF-transponder ear tags in different orientations to reader antennas. Described in this paper is the constructional development and functionality of the test bench as well as trials to determine reproducibility, influence of two trial parameters and suitability of the test bench for the required purpose. The results demonstrate that the test bench fulfilled all the stipulated requirements and enabled a preliminary selection of suitable types of UHF ear tags for use in practice.

  10. Musical experience sharpens human cochlear tuning.

    Science.gov (United States)

    Bidelman, Gavin M; Nelms, Caitlin; Bhagat, Shaum P

    2016-05-01

    The mammalian cochlea functions as a filter bank that performs a spectral, Fourier-like decomposition on the acoustic signal. While tuning can be compromised (e.g., broadened with hearing impairment), whether or not human cochlear frequency resolution can be sharpened through experiential factors (e.g., training or learning) has not yet been established. Previous studies have demonstrated sharper psychophysical tuning curves in trained musicians compared to nonmusicians, implying superior peripheral tuning. However, these findings are based on perceptual masking paradigms, and reflect engagement of the entire auditory system rather than cochlear tuning, per se. Here, by directly mapping physiological tuning curves from stimulus frequency otoacoustic emissions (SFOAEs)-cochlear emitted sounds-we show that estimates of human cochlear tuning in a high-frequency cochlear region (4 kHz) is further sharpened (by a factor of 1.5×) in musicians and improves with the number of years of their auditory training. These findings were corroborated by measurements of psychophysical tuning curves (PTCs) derived via simultaneous masking, which similarly showed sharper tuning in musicians. Comparisons between SFOAE and PTCs revealed closer correspondence between physiological and behavioral curves in musicians, indicating that tuning is also more consistent between different levels of auditory processing in trained ears. Our findings demonstrate an experience-dependent enhancement in the resolving power of the cochlear sensory epithelium and the spectral resolution of human hearing and provide a peripheral account for the auditory perceptual benefits observed in musicians. Both local and feedback (e.g., medial olivocochlear efferent) mechanisms are discussed as potential mechanisms for experience-dependent tuning. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Serving Deaf Students Who Have Cochlear Implants. PEPNet Tipsheet

    Science.gov (United States)

    Searls, J. Matt, Comp.

    2010-01-01

    Cochlear implants (CIs) are complex electronic devices surgically implanted under the skin behind the ear. These devices utilize electrodes placed in the inner ear (the cochlea) to stimulate the auditory nerve of individuals with significant permanent hearing loss. Cochlear implants may not be suitable for everyone. They are designed to provide…

  12. The preoperative imaging evaluation for cochlear implantation

    International Nuclear Information System (INIS)

    Liu Zhonglin; Wang Zhenchang; Fu Lin; Li Yong; Xian Junfang; Yang Bentao; Lan Baosen; Li Yongxin; Zheng Jun; Song Yan; Liu Bo; Chen Xueqing; He Haili

    2006-01-01

    Objective: To analyze CT and MRI findings of temporal bone and to evaluate preoperative diagnostic value for cochlear implantation. Methods: One hundred and sixty candidates for cochlear implantation were examined with axial CT scan, 64 of them also with coronal CT scan, and 119 patients with MRI. Results: All of 320 ears were well-aerated, and 206 ears had mastoid cavities extended posteriorly to the sigmoid sinus. The length from posterior-lateral tympanic wall to the outer cortex was (2.34±0.42) mm (left side) and (2.25±0.40) mm (right side) (U=1.887, P 1 and T 2 signal on MRI. The congenital malformations of inner ear occurred in 67 ears, including complete dysplasia in 1 ear, cochlear hypodysplasia in 6 ears, Mondini deformation in 5 ears, enlarged vestibular aqueduct in 40 ears, dysplastic semicircular canal and the vestibulae in 10 ears, and narrowing of internal auditory canal in 5 ears. Conclusion: Preoperative imaging examinations can provide critical information to ensure successful cochlear' implantation. (authors)

  13. The Effects of Age at Cleft Palate Repair on Middle Ear Function and Hearing Level.

    Science.gov (United States)

    Lou, Qun; Zhu, Hongping; Luo, Yi; Zhou, Zhibo; Ma, Lian; Ma, Xiaoran; Fu, Yuan

    2018-05-01

    To investigate the age effects of cleft palate repair on middle ear function and hearing level in patients who underwent cleft palate repair at different ages by audiologic examination. Medical histories were gathered in detail, and audiologic tests (ie, tympanometry and pure tone hearing threshold) were conducted in 126 patients after palatoplasty. The patients were divided into the following 4 groups according to their ages when they underwent cleft palate repair: group I (0-3 years, 73 patients), group II (4-7 years, 29 patients), group III (8-11 years, 16 patients), and group IV (12 years and older, 8 patients). The data regarding tympanograms, hearing levels, and the average hearing thresholds of each group were analyzed using chi-square tests. The prevalence of middle ear dysfunction and hearing loss in the patients who underwent palatoplasty before 3 years old (27.4% and 2.0% respectively) was significantly lower than that in patients who underwent palatopalsty at 12 years or older (75.0% and 43.7%, respectively). Linear-by-linear association revealed that the prevalences of middle ear dysfunction and hearing loss among the 4 groups were significantly different ( P cleft palate repair. From an audiologist's perspective, palatoplasty at an early age is very beneficial in helping children with cleft palates acquire better middle ear function and hearing level.

  14. Cochlear implant assessment: imaging issues

    Energy Technology Data Exchange (ETDEWEB)

    Marsot-Dupuch, K. E-mail: kathlyn.marsot-dupuch@bct.ap-hop-paris.fr; Meyer, B

    2001-11-01

    Cochlear implants are electronic auditory prostheses used to rehabilitate deafened persons who have lost their hair cells. They are partly worn externally and partly implanted in the ear. They provide a direct stimulation of the spiral ganglion cells of the cochlear nerve by bypassing the destroyed hair cells. The objectives of this article are to summarise what head and neck surgeons need to know before cochlear implantation and to describe the imaging study protocol used and anomalies to look for. A few explanations are resumed about placement of a brainstem implant.

  15. Deriving cochlear delays in humans using otoacoustic emissions and auditory evoked potentials

    DEFF Research Database (Denmark)

    Pigasse, Gilles

    A great deal of the processing of incoming sounds to the auditory system occurs within the cochlear. The organ of Corti within the cochlea has differing mechanical properties along its length that broadly gives rise to frequency selectivity. Its stiffness is at maximum at the base and decreases...... relation between frequency and travel time in the cochlea defines the cochlear delay. This delay is directly associated with the signal analysis occurring in the inner ear and is therefore of primary interest to get a better knowledge of this organ. It is possible to estimate the cochlear delay by direct...... and ASSR latency estimates demonstrated similar rates of latency decrease as a function of frequency. It was further concluded, in this thesis, that OAE measurements are the most appropriate to estimate cochlear delays, since they had the best repeatability and the shortest recording time. Preliminary...

  16. Cochlear infrastructure for electrical hearing

    Science.gov (United States)

    Pfingst, Bryan E.; Bowling, Sara A.; Colesa, Deborah J.; Garadat, Soha N.; Raphael, Yehoash; Shibata, Seiji B.; Strahl, Stefan B.; Su, Gina L.; Zhou, Ning

    2011-01-01

    Although the cochlear implant is already the world's most successful neural prosthesis, opportunities for further improvement abound. Promising areas of current research include work on improving the biological infrastructure in the implanted cochlea to optimize reception of cochlear implant stimulation and on designing the pattern of electrical stimulation to take maximal advantage of conditions in the implanted cochlea. In this review we summarize what is currently known about conditions in the cochlea of deaf, implanted humans and then review recent work from our animal laboratory investigating the effects of preserving or reinnervating tissues on psychophysical and electrophysiological measures of implant function. Additionally we review work from our human laboratory on optimizing the pattern of electrical stimulation to better utilize strengths in the cochlear infrastructure. Histological studies of human temporal bones from implant users and from people who would have been candidates for implants show a range of pathologic conditions including spiral ganglion cell counts ranging from approximately 2% to 92% of normal and partial hair cell survival in some cases. To duplicate these conditions in a guinea pig model, we use a variety of deafening and implantation procedures as well as post1-deafening therapies designed to protect neurons and/or regenerate neurites. Across populations of human patients, relationships between nerve survival and functional measures such as speech have been difficult to demonstrate, possibly due to the numerous subject variables that can affect implant function and the elapsed time between functional measures and postmortem histology. However, psychophysical studies across stimulation sites within individual human subjects suggest that biological conditions near the implanted electrodes contribute significantly to implant function, and this is supported by studies in animal models comparing histological findings to psychophysical

  17. Sparc (Osteonectin) functions in morphogenesis of the pharyngeal skeleton and inner ear.

    Science.gov (United States)

    Rotllant, Josep; Liu, Dong; Yan, Yin-Lin; Postlethwait, John H; Westerfield, Monte; Du, Shao-Jun

    2008-07-01

    Sparc (Osteonectin), a matricellular glycoprotein expressed by many differentiated cells, is a major non-collagenous constituent of vertebrate bones. Recent studies indicate that Sparc expression appears early in development, although its function and regulation during embryogenesis are largely unknown. We cloned zebrafish sparc and investigated its role during development, using a mo rpholino antisense oligonucleotide-based knockdown approach. Consistent with its strong expression in the otic vesicle and developing pharyngeal cartilages, knockdown of Sparc function resulted in specific inner ear and cartilage defects that are highlighted by changes in gene expression, morphology and behavior. We rescued the knockdown phenotypes by co-injecting sparc mRNA, providing evidence that the knockdown phenotype is due specifically to impairment of Sparc function. A comparison of the phenotypes of Sparc knockdown and known zebrafish mutants with similar defects places Sparc downstream of sox9 in the genetic network that regulates development of the pharyngeal skeleton and inner ear of vertebrates.

  18. Lead roles for supporting actors: critical functions of inner ear supporting cells.

    Science.gov (United States)

    Monzack, Elyssa L; Cunningham, Lisa L

    2013-09-01

    Many studies that aim to investigate the underlying mechanisms of hearing loss or balance disorders focus on the hair cells and spiral ganglion neurons of the inner ear. Fewer studies have examined the supporting cells that contact both of these cell types in the cochlea and vestibular end organs. While the roles of supporting cells are still being elucidated, emerging evidence indicates that they serve many functions vital to maintaining healthy populations of hair cells and spiral ganglion neurons. Here we review recent studies that highlight the critical roles supporting cells play in the development, function, survival, death, phagocytosis, and regeneration of other cell types within the inner ear. Many of these roles have also been described for glial cells in other parts of the nervous system, and lessons from these other systems continue to inform our understanding of supporting cell functions. This article is part of a Special Issue entitled "Annual Reviews 2013". Published by Elsevier B.V.

  19. Executive Functioning Skills in Preschool-Age Children With Cochlear Implants

    Science.gov (United States)

    Beer, Jessica; Kronenberger, William G.; Castellanos, Irina; Colson, Bethany G.; Henning, Shirley C.; Pisoni, David B.

    2014-01-01

    Purpose The purpose of this study was to determine whether deficits in executive functioning (EF) in children with cochlear implants (CIs) emerge as early as the preschool years. Method Two groups of children ages 3 to 6 years participated in this cross-sectional study: 24 preschoolers who had CIs prior to 36 months of age and 21 preschoolers with normal hearing (NH). All were tested on normed measures of working memory, inhibition-concentration, and organization-integration. Parents completed a normed rating scale of problem behaviors related to EF. Comparisons of EF skills of children with CIs were made to peers with NH and to published nationally representative norms. Results Preschoolers with CIs showed significantly poorer performance on inhibition-concentration and working memory compared with peers with NH and with national norms. No group differences were found in visual memory or organization-integration. When data were controlled for language, differences in performance measures of EF remained, whereas differences in parent-reported problems with EF were no longer significant. Hearing history was generally unrelated to EF. Conclusions This is the first study to demonstrate that EF deficits found in older children with CIs begin to emerge as early as preschool years. The ability to detect these deficits early has important implications for early intervention and habilitation after cochlear implantation. PMID:24686747

  20. From ear to uncertainty: Vestibular contributions to cognitive function.

    Directory of Open Access Journals (Sweden)

    Paul eSmith

    2013-11-01

    Full Text Available In addition to the deficits in the vestibulo-ocular and vestibulo-spinal reflexes that occur following vestibular dysfunction, there is substantial evidence that vestibular loss also causes cognitive disorders, some of which may be due to the reflexive deficits and some of which are related to the role that ascending vestibular pathways to the limbic system and cortex play in spatial orientation. In this review we summarise the evidence that vestibular loss causes cognitive disorders, especially spatial memory deficits, in animals and humans and critically evaluate the evidence that these deficits are not due to hearing loss, problems with motor control, oscillopsia or anxiety and depression. We review the evidence that vestibular lesions affect head direction and place cells as well as the emerging evidence that artificial activation of the vestibular system, using galvanic vestibular stimulation, can modulate cognitive function.

  1. Magnetically induced behaviour of ferritin corpuscles in avian ears: can cuticulosomes function as magnetosomes?

    Science.gov (United States)

    Jandacka, Petr; Burda, Hynek; Pistora, Jaromir

    2015-01-01

    Magnetoreception is an enigmatic, poorly understood sensory ability, described mainly on the basis of behavioural studies in animals of diverse taxa. Recently, corpuscles containing superparamagnetic iron-storage protein ferritin were found in the inner ear hair cells of birds, a predominantly single ferritin corpuscle per cell. It was suggested that these corpuscles might represent magnetosomes and function as magnetosensors. Here we determine ferritin low-field paramagnetic susceptibility to estimate its magnetically induced intracellular behaviour. Physical simulations show that ferritin corpuscles cannot be deformed or rotate in weak geomagnetic fields, and thus cannot provide magnetoreception via deformation of the cuticular plate. Furthermore, we reached an alternative hypothesis that ferritin corpuscle in avian ears may function as an intracellular electromagnetic oscillator. Such an oscillator would generate additional cellular electric potential related to normal cell conditions. Though the phenomenon seems to be weak, this effect deserves further analyses. PMID:25551148

  2. Age and Gender Effects on Wideband Absorbance in Adults with Normal Outer and Middle Ear Function

    Science.gov (United States)

    Mazlan, Rafidah; Kei, Joseph; Ya, Cheng Li; Yusof, Wan Nur Hanim Mohd; Saim, Lokman; Zhao, Fei

    2015-01-01

    Purpose: This study examined the effects of age and gender on wideband energy absorbance in adults with normal middle ear function. Method: Forty young adults (14 men, 26 women, aged 20-38 years), 31 middle-aged adults (16 men, 15 women, aged 42-64 years), and 30 older adults (20 men, 10 women, aged 65-82 years) were assessed. Energy absorbance…

  3. From shared lineage to distinct functions: the development of the inner ear and epibranchial placodes.

    Science.gov (United States)

    Ladher, Raj K; O'Neill, Paul; Begbie, Jo

    2010-06-01

    The inner ear and the epibranchial ganglia constitute much of the sensory system in the caudal vertebrate head. The inner ear consists of mechanosensory hair cells, their neurons, and structures necessary for sound and balance sensation. The epibranchial ganglia are knots of neurons that innervate and relay sensory signals from several visceral organs and the taste buds. Their development was once thought to be independent, in line with their independent functions. However, recent studies indicate that both systems arise from a morphologically distinct common precursor domain: the posterior placodal area. This review summarises recent studies into the induction, morphogenesis and innervation of these systems and discusses lineage restriction and cell specification in the context of their common origin.

  4. [Biomaterials in cochlear implants].

    Science.gov (United States)

    Stöver, T; Lenarz, T

    2009-05-01

    Cochlear implants (CI) represent the "gold standard" for the treatment of congenitally deaf children and postlingually deafened adults. Thus, cochlear implantation is a success story of new bionic prosthesis development. Owing to routine application of cochlear implants in adults but also in very young children (below the age of one), high demands are placed on the implants. This is especially true for biocompatibility aspects of surface materials of implant parts which are in contact with the human body. In addition, there are various mechanical requirements which certain components of the implants must fulfil, such as flexibility of the electrode array and mechanical resistance of the implant housing. Due to the close contact of the implant to the middle ear mucosa and because the electrode array is positioned in the perilymphatic space via cochleostomy, there is a potential risk of bacterial transferral along the electrode array into the cochlea. Various requirements that have to be fulfilled by cochlear implants, such as biocompatibility, electrode micromechanics, and although a very high level of technical standards has been carried out there is still demand for the improvement of implants as well as of the materials used for manufacturing, ultimately leading to increased implant performance. General considerations of material aspects related to cochlear implants as well as potential future perspectives of implant development will be discussed.

  5. Transcanal labyrinthectomy for intractable vertigo after unilateral cochlear implantation.

    Science.gov (United States)

    Heidenreich, Katherine D; Basura, Gregory J; Zwolan, Teresa A; El-Kashlan, Hussam K; Telian, Steven A

    2011-10-01

    Document the use of transcanal labyrinthectomy to treat disabling attacks of vertigo after unilateral cochlear implantation. A 46-year-old woman with severe-profound bilateral sensorineural hearing loss secondary to enlarged vestibular aqueducts underwent cochlear implantation for her right ear with a Nucleus Freedom device. The surgery was uneventful, and postoperative imaging confirmed that the electrode was positioned properly. She developed episodic vertigo 10 to 14 days after the implant surgery, which failed to improve with aggressive vestibular rehabilitation therapy. Plugging of the round window for possible perilymphatic fistula did not relieve her symptoms. Right transcanal labyrinthectomy supplemented by filling the vestibule with gentamicin-soaked Gelfoam and then a customized vestibular rehabilitation program. Comparison of vestibular symptoms and cochlear implant performance before and after transcanal labyrinthectomy. The patient had immediate relief of symptoms, and the function of the cochlear implant was not adversely affected. Transcanal labyrinthectomy may be an effective method to ablate the vestibular end organ after unilateral cochlear implantation. It can offer relief of disabling vertigo without adversely affecting the performance of the implant.

  6. Evidence for a functional subdivision of Premotor Ear-Eye Field (Area 8B.

    Directory of Open Access Journals (Sweden)

    Marco eLanzilotto

    2015-01-01

    Full Text Available The Supplementary Eye Field (SEF and the Frontal Eye Field (FEF have been described as participating in gaze shift control. Recent evidence suggests, however, that other areas of the dorsomedial prefrontal cortex also influence gaze shift. Herein, we have investigated electrically evoked ear- and eye movements from the Premotor Ear-Eye Field, or PEEF (area 8B of macaque monkeys. We stimulated PEEF during spontaneous condition (outside the task performance and during the execution of a visual fixation task (VFT. In the first case, we functionally identified two regions within the PEEF: a core and a belt. In the core region, stimulation elicited forward ear movements; regarding the evoked eye movements, in some penetrations, stimulation elicited contraversive fixed-vectors with a mean amplitude of 5.14°; while in other penetrations, we observed prevalently contralateral goal-directed eye movements having end-points that fell within 15° in respect to the primary eye position. On the contrary, in the belt region, stimulation elicited backward ear movements; regarding the eye movements, in some penetrations stimulation elicited prevalently contralateral goal-directed eye movements having end-points that fell within 15° in respect to the primary eye position, while in the lateral edge of the investigated region, stimulation elicited contralateral goal-directed eye movements having end-points that fell beyond 15° in respect to the primary eye position. Stimulation during VFT either did not elicit eye movements or evoked saccades of only a few degrees. Finally, even though no head rotation movements were observed during the stimulation period, we viewed a relationship between the duration of stimulation and the neck forces exerted by the monkey’s head. We propose an updated vision of the PEEF composed of two functional regions, core and belt, which may be involved in integrating auditory and visual information important to the programming of gaze

  7. Impaired Vestibular Function After Cochlear Implantation in Children: Role of Static Posturography.

    Science.gov (United States)

    Nair, Satish; Gupta, Atul; Nilakantan, Ajith; Mittal, Ruchika; Dahiya, Ruchi; Saini, Sachin; Prasad, Rachana; Vajpayee, Deepika

    2017-06-01

    To identify vestibular dysfunction in children after cochlear implant surgery and to study the utility of static posturography in evaluating vestibular function in children. A prospective study was carried out on 25 children between 2 and 7 years of age with sensorineural hearing loss with no overt vestibular dysfunction. All children underwent static posturography using Synapsis Posturographic System (SPS) software (Version 3.0, REV C) using a static platform with foam. The centre of pressure (COP) shift was recorded as statokinesiogram on the software and the mean vestibular, visual and somesthetic scores were obtained. Cochlear implantation (CI) surgery was done with insertion of Med-El Pulsar standard cochlear implant with 12 twin electrodes. Children were evaluated again after 4 weeks of CI surgery (2 weeks after switch on) with static posturography on the same SPS software. The scores obtained were compared with pre op value and data analyzed statistically by paired t tests on SPSS 18 software. The mean age was 4.6 years with range 2-7 years. All the children in the study were able to complete the test with no difficulty and the mean time required for each child was 10.2 min. The mean pre op somesthetic score was 95.16 (SD 1.52) and post op score was 94.06 (SD 1.79). The mean pre op visual score was 86.64 (SD 2.24) and post op score was 82.55 (2.89). The mean pre op vestibular score was 84.11 (SD 2.20) and post op score was 73.66 (SD 4.25). Correlation and statistical analysis of the pre and post values of each score revealed statistically significant reduction in vestibular scores post CI. The vestibular system is at high risk of injury leading to vestibular dysfunction in children during CI. Our study found the static posturography as a simple, fast and efficient tool to screen children for vestibular dysfunction post CI. Identifying the dysfunction early can help in initiating early rehabilitation measures.

  8. [Cochlear implantation through the middle fossa approach].

    Science.gov (United States)

    Szyfter, W; Colletti, V; Pruszewicz, A; Kopeć, T; Szymiec, E; Kawczyński, M; Karlik, M

    2001-01-01

    The inner part of cochlear implant is inserted into inner ear during surgery through mastoid and middle ear. It is a classical method, used in the majority cochlear centers in the world. This is not a suitable method in case of chronic otitis media and middle ear malformation. In these cases Colletti proposed the middle fossa approach and cochlear implant insertion omitting middle ear structures. In patient with bilateral chronic otitis media underwent a few ears operations without obtaining dry postoperative cavity. Cochlear implantation through the middle fossa approach was performed in this patient. The bone fenster was cut, temporal lobe was bent and petrosus pyramid upper surface was exposed. When the superficial petrosal greater nerve, facial nerve and arcuate eminence were localised, the cochlear was open in the basal turn and electrode were inserted. The patient achieves good results in the postoperative speech rehabilitation. It confirmed Colletti tesis that deeper electrode insertion in the cochlear implantation through the middle fossa approach enable use of low and middle frequencies, which are very important in speech understanding.

  9. Evolution and development of hair cell polarity and efferent function in the inner ear.

    Science.gov (United States)

    Sienknecht, Ulrike J; Köppl, Christine; Fritzsch, Bernd

    2014-01-01

    The function of the inner ear critically depends on mechanoelectrically transducing hair cells and their afferent and efferent innervation. The first part of this review presents data on the evolution and development of polarized vertebrate hair cells that generate a sensitive axis for mechanical stimulation, an essential part of the function of hair cells. Beyond the cellular level, a coordinated alignment of polarized hair cells across a sensory epithelium, a phenomenon called planar cell polarity (PCP), is essential for the organ's function. The coordinated alignment of hair cells leads to hair cell orientation patterns that are characteristic of the different sensory epithelia of the vertebrate inner ear. Here, we review the developmental mechanisms that potentially generate molecular and morphological asymmetries necessary for the control of PCP. In the second part, this review concentrates on the evolution, development and function of the enigmatic efferent neurons terminating on hair cells. We present evidence suggestive of efferents being derived from motoneurons and synapsing predominantly onto a unique but ancient cholinergic receptor. A review of functional data shows that the plesiomorphic role of the efferent system likely was to globally shut down and protect the peripheral sensors, be they vestibular, lateral line or auditory hair cells, from desensitization and damage during situations of self-induced sensory overload. The addition of a dedicated auditory papilla in land vertebrates appears to have favored the separation of vestibular and auditory efferents and specializations for more sophisticated and more diverse functions. © 2014 S. Karger AG, Basel.

  10. Thrombospondins 1 and 2 are important for afferent synapse formation and function in the inner ear.

    Science.gov (United States)

    Mendus, Diana; Sundaresan, Srividya; Grillet, Nicolas; Wangsawihardja, Felix; Leu, Rose; Müller, Ulrich; Jones, Sherri M; Mustapha, Mirna

    2014-04-01

    Thrombospondins (TSPs) constitute a family of secreted extracellular matrix proteins that have been shown to be involved in the formation of synapses in the central nervous system. In this study, we show that TSP1 and TSP2 are expressed in the cochlea, and offer the first description of their putative roles in afferent synapse development and function in the inner ear. We examined mice with deletions of TSP1, TSP2 and both (TSP1/TSP2) for inner ear development and function. Immunostaining for synaptic markers indicated a significant decrease in the number of formed afferent synapses in the cochleae of TSP2 and TSP1/TSP2 knockout (KO) mice at postnatal day (P)29. In functional studies, TSP2 and TSP1/TSP2 KO mice showed elevated auditory brainstem response (ABR) thresholds as compared with wild-type littermates, starting at P15, with the most severe phenotype being seen for TSP1/TSP2 KO mice. TSP1/TSP2 KO mice also showed reduced wave I amplitudes of ABRs and vestibular evoked potentials, suggesting synaptic dysfunction in both the auditory and vestibular systems. Whereas ABR thresholds in TSP1 KO mice were relatively unaffected at early ages, TSP1/TSP2 KO mice showed the most severe phenotype among all of the genotypes tested, suggesting functional redundancy between the two genes. On the basis of the above results, we propose that TSPs play an important role in afferent synapse development and function of the inner ear. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  11. Congenital malformation of inner ear, single cavity

    International Nuclear Information System (INIS)

    Torres Pazmino, Julio Cesar; Marrugo Pardo, Gilberto Eduardo

    2010-01-01

    Congenital malformations of the inner ear are rare conditions, but their detection requires high diagnostic accuracy. In this report we describe the case of a patient with single or common cavity, discuss the corresponding radiological images, describe the treatment of this patient with a cochlear implant, and review the classification and differential diagnosis of the other anomalies of the inner ear.

  12. Function of the sexually dimorphic ear of the American bullfrog, Rana catesbeiana: brief review and new insight.

    Science.gov (United States)

    Werner, Y L; Pylka, J; Schneider, H; Seifan, M; Walkowiak, W; Werner-Reiss, U

    2009-07-01

    The dimorphic ear of the bullfrog, Rana catesbeiana, has long been enigmatic. The male's tympanic membrane (TM) area approximates twice the area of the female's; however, similar size differences in the area of the columellar footplate were not observed between the sexes. Hence, the male's hearing is expected to be more sensitive than the female's but this is not the case. Asking what offsets the advantage of the large TM, we applied a series of experiments to the auditory system. Male and female audiograms based on stimulation with airborne sound and on both multi-unit responses from the brain and alternating cochlear potentials ('microphonics') showed equal sensitivity and a small difference in frequency response; at low frequencies the male was more sensitive than the female. Amputating the columella and stimulating the stump with mechanical vibration showed that for an equal microphonic response, the male's footplate vibrated with lower amplitude than the female's footplate. Mechanically stimulating the TM of the intact ear replicated this result, excluding the involvement of the mechanical lever. The TM of the male weighs five times the TM of the female, and artificial loading of the TM of either sex greatly reduced the ear's sensitivity. Hence, the male's excessive area ratio (TM to columellar footplate) is offset by the heavier cartilage cushion on the male's TM, damping the TM's response to sound. This is corroborated by experimentally artificially loading the TM. The product of area ratio and footplate vibration amplitude would result in similar stimulation of the inner ear in the two sexes.

  13. CT study of 17 cases of congenital cochlear abnormality. Embryologic and anatomo-functional relationship

    OpenAIRE

    Maurício, JC; Biscoito, L; Branco, G

    1993-01-01

    In this review of cochlear malformations, 17 cases were studied by CT scan (high resolution-target program) including 10 males and 7 females. The anomaly was bilateral in 12 cases and unilateral in 7 (the latter included 2 Mondini type aplasias and one Michel). The cochlear malformation (whose most frequent expression was the cochlear hypoplasia with 1 or 1 1/2 spires-65% of the cases) was associated to semicircular canals and/or vestibular aqueduct anomaly in 82% of the patients; it was excl...

  14. The cochlear nerve canal and internal auditory canal in children with normal cochlea but cochlear nerve deficiency

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Fei; Li, Jianhong; Xian, Junfang; Wang, Zhenchang [Dept. of Radiology, Beijing Tongren Hospital, Capital Medical Univ., Beijing (China)], e-mail: cjr.wzhch@vip.163.com; Mo, Lingyan [Dept. of Otorhinolaryngology, Beijing Tongren Hospital, Capital Medical Univ., Beijing (China)

    2013-04-15

    Background: There is an increasing frequency of requests for cochlear implantation (CI) in deaf children and more detailed image information is necessary for selecting appropriate candidates. Cochlear nerve deficiency (CND) is a contraindication to CI. Magnetic resonance imaging (MRI) has been used to evaluate the integrity of the cochlear nerve. The abnormalities of the cochlear nerve canal (CNC) and internal auditory canal (IAC) have been reported to be associated with CND. Purpose: To correlate CNC manifestation, size, and IAC diameter on high-resolution CT (HRCT) with CND diagnosed by MRI in children. Material and Methods: HRCT images from 35 sensorineurally deaf children who had normal cochlea but bilateral or unilateral CND diagnosed by MRI were studied retrospectively. The CNC and IAC manifestation and size were assessed and correlated with CND. Results: CND was diagnosed by MRI in 54/70 ears (77.1%). Thirty-two ears had an absent cochlear nerve (59.3%), while 22 ears had a small cochlear nerve (40.7%). The CNC diameter was <1.5 mm in 36 ears (66.7%). The CNC diameter ranged between 1.5 and 2.0 mm in seven ears (13.0%) and was >2.0 mm in 11 ears (20.4%). The IAC diameter was <3.0 mm in 25 ears (46.3%) and >3.0 mm in 29 ears (53.7%). Conclusion: The hypoplastic CNC might be more highly indicative of CND than that of a narrow IAC.

  15. Finding an analytic description of the resolution function for n_TOF-EAR2 at CERN

    CERN Document Server

    Eriksson, John Benjamin

    2017-01-01

    At CERN's neutron time-of-flight facility n_TOF a high intensity pulsed neutron source is used to measure energy-dependent neutron-induced reaction cross sections of isotopes relevant to various fields of research such as nuclear astrophysics, -technology or -medicine. Neutron kinetic energies are determined using the time-of-flight (ToF) technique. A correct ToF to energy conversion is essential and is influenced by many factors, one of which is the so-called resolution function (RF). The RF is a characteristic unique to each experimental facility and can only be determined through simulations using Monte Carlo codes. The goal of this project is to find an analytic description of the RF for n_TOF-EAR2. Two functions for two different energy ranges were found, each a combination of linear, polynomial and exponential functions. Furthermore, the energy dependence of the function's parameters was investigated.

  16. Reduction in noise-induced functional loss of the cochleae in mice with pre-existing cochlear dysfunction due to genetic interference of prestin.

    Science.gov (United States)

    Cai, Qunfeng; Wang, Bo; Coling, Donald; Zuo, Jian; Fang, Jie; Yang, Shiming; Vera, Krystal; Hu, Bo Hua

    2014-01-01

    Various cochlear pathologies, such as acoustic trauma, ototoxicity and age-related degeneration, cause hearing loss. These pre-existing hearing losses can alter cochlear responses to subsequent acoustic overstimulation. So far, the knowledge on the impacts of pre-existing hearing loss caused by genetic alteration of cochlear genes is limited. Prestin is the motor protein expressed exclusively in outer hair cells in the mammalian cochlea. This motor protein contributes to outer hair cell motility. At present, it is not clear how the interference of prestin function affects cochlear responses to acoustic overstimulation. To address this question, a genetic model of prestin dysfunction in mice was created by inserting an internal ribosome entry site (IRES)-CreERT2-FRT-Neo-FRT cassette into the prestin locus after the stop codon. Homozygous mice exhibit a threshold elevation of auditory brainstem responses with large individual variation. These mice also display a threshold elevation and a shift of the input/output function of the distortion product otoacoustic emission, suggesting a reduction in outer hair cell function. The disruption of prestin function reduces the threshold shifts caused by exposure to a loud noise at 120 dB (sound pressure level) for 1 h. This reduction is positively correlated with the level of pre-noise cochlear dysfunction and is accompanied by a reduced change in Cdh1 expression, suggesting a reduction in molecular responses to the acoustic overstimulation. Together, these results suggest that prestin interference reduces cochlear stress responses to acoustic overstimulation.

  17. Reduction in noise-induced functional loss of the cochleae in mice with pre-existing cochlear dysfunction due to genetic interference of prestin.

    Directory of Open Access Journals (Sweden)

    Qunfeng Cai

    Full Text Available Various cochlear pathologies, such as acoustic trauma, ototoxicity and age-related degeneration, cause hearing loss. These pre-existing hearing losses can alter cochlear responses to subsequent acoustic overstimulation. So far, the knowledge on the impacts of pre-existing hearing loss caused by genetic alteration of cochlear genes is limited. Prestin is the motor protein expressed exclusively in outer hair cells in the mammalian cochlea. This motor protein contributes to outer hair cell motility. At present, it is not clear how the interference of prestin function affects cochlear responses to acoustic overstimulation. To address this question, a genetic model of prestin dysfunction in mice was created by inserting an internal ribosome entry site (IRES-CreERT2-FRT-Neo-FRT cassette into the prestin locus after the stop codon. Homozygous mice exhibit a threshold elevation of auditory brainstem responses with large individual variation. These mice also display a threshold elevation and a shift of the input/output function of the distortion product otoacoustic emission, suggesting a reduction in outer hair cell function. The disruption of prestin function reduces the threshold shifts caused by exposure to a loud noise at 120 dB (sound pressure level for 1 h. This reduction is positively correlated with the level of pre-noise cochlear dysfunction and is accompanied by a reduced change in Cdh1 expression, suggesting a reduction in molecular responses to the acoustic overstimulation. Together, these results suggest that prestin interference reduces cochlear stress responses to acoustic overstimulation.

  18. Inner ear pressure changes following square wave intracranial or ear canal pressure manipulation in the same guinea pig

    NARCIS (Netherlands)

    Thalen, E; Wit, H; Segenhout, H; Albers, F

    Inner ear pressure was measured in scala tympani with a micropipette during square wave pressure manipulation of the intracranial compartment and, subsequently, of the external ear canal (EEC) in the same guinea pig. As expected, the combination of the cochlear aqueduct and the inner ear behaves as

  19. Temporal modulation transfer functions in cochlear implantees using a method that limits overall loudness cues

    Science.gov (United States)

    Fraser, Matthew; McKay, Colette M.

    2012-01-01

    Temporal modulation transfer functions (TMTFs) were measured for six users of cochlear implants, using different carrier rates and levels. Unlike most previous studies investigating modulation detection, the experimental design limited potential effects of overall loudness cues. Psychometric functions (percent correct discrimination of modulated from unmodulated stimuli versus modulation depth) were obtained. For each modulation depth, each modulated stimulus was loudness balanced to the unmodulated reference stimulus, and level jitter was applied in the discrimination task. The loudness-balance data showed that the modulated stimuli were louder than the unmodulated reference stimuli with the same average current, thus confirming the need to limit loudness cues when measuring modulation detection. TMTFs measured in this way had a low-pass characteristic, with a cut-off frequency (at comfortably loud levels) similar to that for normal-hearing listeners. A reduction in level caused degradation in modulation detection efficiency and a lower-cut-off frequency (i.e. poorer temporal resolution). An increase in carrier rate also led to a degradation in modulation detection efficiency, but only at lower levels or higher modulation frequencies. When detection thresholds were expressed as a proportion of dynamic range, there was no effect of carrier rate for the lowest modulation frequency (50 Hz) at either level. PMID:22146425

  20. Relations Between Self-reported Executive Functioning and Speech Perception Skills in Adult Cochlear Implant Users.

    Science.gov (United States)

    Moberly, Aaron C; Patel, Tirth R; Castellanos, Irina

    2018-02-01

    As a result of their hearing loss, adults with cochlear implants (CIs) would self-report poorer executive functioning (EF) skills than normal-hearing (NH) peers, and these EF skills would be associated with performance on speech recognition tasks. EF refers to a group of high order neurocognitive skills responsible for behavioral and emotional regulation during goal-directed activity, and EF has been found to be poorer in children with CIs than their NH age-matched peers. Moreover, there is increasing evidence that neurocognitive skills, including some EF skills, contribute to the ability to recognize speech through a CI. Thirty postlingually deafened adults with CIs and 42 age-matched NH adults were enrolled. Participants and their spouses or significant others (informants) completed well-validated self-reports or informant-reports of EF, the Behavior Rating Inventory of Executive Function - Adult (BRIEF-A). CI users' speech recognition skills were assessed in quiet using several measures of sentence recognition. NH peers were tested for recognition of noise-vocoded versions of the same speech stimuli. CI users self-reported difficulty on EF tasks of shifting and task monitoring. In CI users, measures of speech recognition correlated with several self-reported EF skills. The present findings provide further evidence that neurocognitive factors, including specific EF skills, may decline in association with hearing loss, and that some of these EF skills contribute to speech processing under degraded listening conditions.

  1. Benefits and detriments of unilateral cochlear implant use on bilateral auditory development in children who are deaf

    Directory of Open Access Journals (Sweden)

    Karen A. Gordon

    2013-10-01

    Full Text Available We have explored both the benefits and detriments of providing electrical input through a cochlear implant in one ear to the auditory system of young children. A cochlear implant delivers electrical pulses to stimulate the auditory nerve, providing children who are deaf with access to sound. The goals of implantation are to restrict reorganization of the deprived immature auditory brain and promote development of hearing and spoken language. It is clear that limiting the duration of deprivation is a key factor. Additional considerations are the onset, etiology, and use of residual hearing as each of these can have unique effects on auditory development in the pre-implant period. New findings show that many children receiving unilateral cochlear implants are developing mature-like brainstem and thalamo-cortical responses to sound with long term use despite these sources of variability; however, there remain considerable abnormalities in cortical function. The most apparent, determined by implanting the other ear and measuring responses to acute stimulation, is a loss of normal cortical response from the deprived ear. Recent data reveal that this can be avoided in children by early implantation of both ears simultaneously or with limited delay. We conclude that auditory development requires input early in development and from both ears.

  2. Benefits and detriments of unilateral cochlear implant use on bilateral auditory development in children who are deaf

    Science.gov (United States)

    Gordon, Karen A.; Jiwani, Salima; Papsin, Blake C.

    2013-01-01

    We have explored both the benefits and detriments of providing electrical input through a cochlear implant in one ear to the auditory system of young children. A cochlear implant delivers electrical pulses to stimulate the auditory nerve, providing children who are deaf with access to sound. The goals of implantation are to restrict reorganization of the deprived immature auditory brain and promote development of hearing and spoken language. It is clear that limiting the duration of deprivation is a key factor. Additional considerations are the onset, etiology, and use of residual hearing as each of these can have unique effects on auditory development in the pre-implant period. New findings show that many children receiving unilateral cochlear implants are developing mature-like brainstem and thalamo-cortical responses to sound with long term use despite these sources of variability; however, there remain considerable abnormalities in cortical function. The most apparent, determined by implanting the other ear and measuring responses to acute stimulation, is a loss of normal cortical response from the deprived ear. Recent data reveal that this can be avoided in children by early implantation of both ears simultaneously or with limited delay. We conclude that auditory development requires input early in development and from both ears. PMID:24137143

  3. [Cochlear Implant - State of the Art].

    Science.gov (United States)

    Lenarz, Thomas

    2017-04-01

    Cochlear implants are the treatment of choice for the auditory rehabilitation of patients with sensory deafness. They restore the missing function of inner hair cells by transforming the acoustic signal into electrical stimuli for activation of auditory nerve fibers. Due to the very fast technology development cochlear implants provide open-set speech understanding in the majority of patients including the use of the telephone. Children can achieve a near to normal speech and language development provided their deafness is detected early after onset and implantation is performed quickly thereafter. The diagnostic procedure as well as the surgical techniques have been standardized and can be adapted to the individual anatomical and physiological needs both in children and adults. Special cases such as cochlear obliteration or malformations can be addressed. Device failures and medical complications might require special measures and reimplantation which can be done in most cases in a straight forward way. Technology upgrades count for better performance.Future developments will focus on better electrode nerve interfaces by improving electrode technology. An increased number of electrical contacts as well as the biological treatment with regeneration of the dendrides growing onto the electrode will increase the number of electrical channels. This will give room for improved speech coding strategies in order to create the bionic ear, i. e. to restore the process of natural hearing by means of technology. The robot assisted surgery will allow for high precision surgery and reliable hearing preservation. Biological therapies will support the bionic ear. Methods are biohybrid electrodes which are coded by stem cells transplanted into the inner ear to enhance autoproduction of neurotrophins. Local drug delivery will focus on suppression of trauma reaction and local regeneration. Gene therapy by nanoparticles will hopefully lead to the preservation of residual hearing in

  4. Cochlear implant - state of the art.

    Science.gov (United States)

    Lenarz, Thomas

    2017-01-01

    Cochlear implants are the treatment of choice for auditory rehabilitation of patients with sensory deafness. They restore the missing function of inner hair cells by transforming the acoustic signal into electrical stimuli for activation of auditory nerve fibers. Due to the very fast technology development, cochlear implants provide open-set speech understanding in the majority of patients including the use of the telephone. Children can achieve a near to normal speech and language development provided their deafness is detected early after onset and implantation is performed quickly thereafter. The diagnostic procedure as well as the surgical technique have been standardized and can be adapted to the individual anatomical and physiological needs both in children and adults. Special cases such as cochlear obliteration might require special measures and re-implantation, which can be done in most cases in a straight forward way. Technology upgrades count for better performance. Future developments will focus on better electrode-nerve interfaces by improving electrode technology. An increased number of electrical contacts as well as the biological treatment with regeneration of the dendrites growing onto the electrode will increase the number of electrical channels. This will give room for improved speech coding strategies in order to create the bionic ear, i.e. to restore the process of natural hearing by means of technology. The robot-assisted surgery will allow for high precision surgery and reliable hearing preservation. Biological therapies will support the bionic ear. Methods are bio-hybrid electrodes, which are coded by stem cells transplanted into the inner ear to enhance auto-production of neurotrophins. Local drug delivery will focus on suppression of trauma reaction and local regeneration. Gene therapy by nanoparticles will hopefully lead to the preservation of residual hearing in patients being affected by genetic hearing loss. Overall the cochlear implant

  5. Cochlear implant – state of the art

    Science.gov (United States)

    Lenarz, Thomas

    2018-01-01

    Cochlear implants are the treatment of choice for auditory rehabilitation of patients with sensory deafness. They restore the missing function of inner hair cells by transforming the acoustic signal into electrical stimuli for activation of auditory nerve fibers. Due to the very fast technology development, cochlear implants provide open-set speech understanding in the majority of patients including the use of the telephone. Children can achieve a near to normal speech and language development provided their deafness is detected early after onset and implantation is performed quickly thereafter. The diagnostic procedure as well as the surgical technique have been standardized and can be adapted to the individual anatomical and physiological needs both in children and adults. Special cases such as cochlear obliteration might require special measures and re-implantation, which can be done in most cases in a straight forward way. Technology upgrades count for better performance. Future developments will focus on better electrode-nerve interfaces by improving electrode technology. An increased number of electrical contacts as well as the biological treatment with regeneration of the dendrites growing onto the electrode will increase the number of electrical channels. This will give room for improved speech coding strategies in order to create the bionic ear, i.e. to restore the process of natural hearing by means of technology. The robot-assisted surgery will allow for high precision surgery and reliable hearing preservation. Biological therapies will support the bionic ear. Methods are bio-hybrid electrodes, which are coded by stem cells transplanted into the inner ear to enhance auto-production of neurotrophins. Local drug delivery will focus on suppression of trauma reaction and local regeneration. Gene therapy by nanoparticles will hopefully lead to the preservation of residual hearing in patients being affected by genetic hearing loss. Overall the cochlear implant

  6. Value of high-resolution MR in patients scheduled for cochlear implantation

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, J.; Held, P. [Univ. Hospital, Regensburg (Germany). Dept of Diagnostic Radiology; Waldeck, A. [Univ. Hospital, Regensburg (Germany). Dept of Otorhinolaryngology; Strotzer, M. [Univ. Hospital, Regensburg (Germany). Dept of Diagnostic Radiology; Voelk, J.; Strutz, J. [Univ. Hospital, Regensburg (Germany). Dept of Otorhinolaryngology; Feuerbach, S. [Univ. Hospital, Regensburg (Germany). Dept of Diagnostic Radiology

    2001-11-01

    Objective: To determine sensitivity and specificity of high-resolution MR imaging and of high-resolution axial CT (HRCT) and to compare the two modalities in predicting the surgical and functional success of cochlear implantation. Material and Methods: The presurgical MR images (2D T2W TSE, 3D T2*W CISS, plain and contrast-enhanced 3D T1W MP-RAGE) and axial HRCT findings of 26 patients were evaluated with regard to the predictive value concerning the success of cochlear implantation. Results: We found a high correlation between MR and HRCT and the success of cochlear implantation. In all 26 patients, the MR-based predictions concerning the success of cochlear implantation were correct. In 10 patients, MR gave additional information to HRCT. In all patients, MR gave sufficient information about the status of the inner ear, inner auditory canal and cochlear nerve to aid the surgeon during the operation. Conclusion: A high-resolution MR protocol consisting of coronal 2D T2W TSE, 3D T2*W axial CISS, plain and contrast-enhanced sagittal T1W 3D MP-RAGE is recommended for the evaluation of candidates scheduled for cochlear implantation. It provides information which cannot be obtained by HRCT.

  7. Your Ears

    Science.gov (United States)

    ... Outer Ear: Catch the Wave The Middle Ear: Good Vibrations The Inner Ear: Nerve Signals Start Here Day or Night, Ears Keep You Upright Three Cheers for the Ears! en español Tus oídos Did you hear something? Maybe the sound you heard was as quiet as your cat licking her paws. Or maybe it was loud, ...

  8. Perception of Music and Speech in Adolescents with Cochlear Implants – A Pilot Study on Effects of Intensive Musical Ear Training

    DEFF Research Database (Denmark)

    Petersen, Bjørn; Sørensen, Stine Derdau; Pedersen, Ellen Raben

    measures of rehabilitation are important throughout adolescence. Music training may provide a beneficial method of strengthening not only music perception, but also linguistic skills, particularly prosody. The purpose of this study was to examine perception of music and speech and music engagement...... of adolescent CI users and the potential effects of an intensive musical ear training program. METHODS Eleven adolescent CI users participated in a short intensive training program involving music making activities and computer based listening exercises. Ten NH agemates formed a reference group, who followed...... their standard school schedule and received no music training. Before and after the intervention period, both groups completed a set of tests for perception of music, speech and emotional prosody. In addition, the participants filled out a questionnaire which examined music listening habits and enjoyment...

  9. The role of MRI in suspected inner ear malformations

    International Nuclear Information System (INIS)

    Koesling, S.; Juettemann, S.; Amaya, B.; Rasinski, C.; Bloching, M.; Koenig, E.

    2003-01-01

    Purpose: This is a prospective analysis of the value of MRI in suspected inner ear malformations. Materials and Methods: In 50 patients (43 children and young adults, 7 adults) with suspected inner ear malformation MRI (1.5 T) was performed. In addition, 42 of these patients underwent CT. For the analysis of the inner ear structures, the constructive interference in steady state (CISS) sequence with 0.7 mm slice thickness was used. Functional tests revealed a sensorineural hearing loss or deafness in 82 temporal bones (TB) and a combined hearing loss in 4 TB. The hearing loss was unilateral in 14 patients. MRI and CT findings were compared. Results: Imaging findings were normal in 58 TB. The pathological findings included inner ear malformations (35 TB), inflammatory changes (4 TB), partial obliteration of labyrinth (2 TB) and congenital aural atresia (1 TB). An isolated absence of the cochlear nerve (1 TB) could only be found by MRI. In the remaining cases, an inner ear malformation was diagnosed by MRI and CT with the same confidence but MRI was superior in displaying the fine details. Conclusions: MRI will become the method of choice in the diagnosis of inner ear malformations. (orig.) [de

  10. Cooperative and independent functions of FGF and Wnt signaling during early inner ear development.

    Science.gov (United States)

    Wright, Kevin D; Mahoney Rogers, Amanda A; Zhang, Jian; Shim, Katherine

    2015-10-06

    In multiple vertebrate organisms, including chick, Xenopus, and zebrafish, Fibroblast Growth Factor (FGF) and Wnt signaling cooperate during formation of the otic placode. However, in the mouse, although FGF signaling induces Wnt8a expression during induction of the otic placode, it is unclear whether these two signaling pathways functionally cooperate. Sprouty (Spry) genes encode intracellular antagonists of receptor tyrosine kinase signaling, including FGF signaling. We previously demonstrated that the Sprouty1 (Spry1) and Sprouty2 (Spry2) genes antagonize FGF signaling during induction of the otic placode. Here, we investigate cross talk between FGF/SPRY and Wnt signaling during otic placode induction and assess whether these two signaling pathways functionally cooperate during early inner ear development in the mouse. Embryos were generated carrying combinations of a Spry1 null allele, Spry2 null allele, β-catenin null allele, or a Wnt reporter transgene. Otic phenotypes were assessed by in situ hybridization, semi-quantitative reverse transcriptase PCR, immunohistochemistry, and morphometric analysis of sectioned tissue. Comparison of Spry1, Spry2, and Wnt reporter expression in pre-otic and otic placode cells indicates that FGF signaling precedes and is active in more cells than Wnt signaling. We provide in vivo evidence that FGF signaling activates the Wnt signaling pathway upstream of TCF/Lef transcriptional activation. FGF regulation of Wnt signaling is functional, since early inner ear defects in Spry1 and Spry2 compound mutant embryos can be genetically rescued by reducing the activity of the Wnt signaling pathway. Interestingly, we find that although the entire otic placode increases in size in Spry1 and Spry2 compound mutant embryos, the size of the Wnt-reporter-positive domain does not increase to the same extent as the Wnt-reporter-negative domain. This study provides genetic evidence that FGF and Wnt signaling cooperate during early inner ear

  11. Cochlear synaptopathy in acquired sensorineural hearing loss: Manifestations and mechanisms.

    Science.gov (United States)

    Liberman, M Charles; Kujawa, Sharon G

    2017-06-01

    Common causes of hearing loss in humans - exposure to loud noise or ototoxic drugs and aging - often damage sensory hair cells, reflected as elevated thresholds on the clinical audiogram. Recent studies in animal models suggest, however, that well before this overt hearing loss can be seen, a more insidious, but likely more common, process is taking place that permanently interrupts synaptic communication between sensory inner hair cells and subsets of cochlear nerve fibers. The silencing of affected neurons alters auditory information processing, whether accompanied by threshold elevations or not, and is a likely contributor to a variety of perceptual abnormalities, including speech-in-noise difficulties, tinnitus and hyperacusis. Work described here will review structural and functional manifestations of this cochlear synaptopathy and will consider possible mechanisms underlying its appearance and progression in ears with and without traditional 'hearing loss' arising from several common causes in humans. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Sudden sensorineural hearing loss: Is there a connection with inner ear electrolytic disorders? A literature review.

    Science.gov (United States)

    Ciorba, Andrea; Corazzi, Virginia; Bianchini, Chiara; Aimoni, Claudia; Skarzynski, Henryk; Skarzynski, Piotr Henryk; Hatzopoulos, Stavros

    2016-12-01

    Electrolytic disorders of the inner ear represent a model that could be implicated in partially explaining the pathogenesis of sudden sensorineural hearing loss (SSNHL). Different types of electrolytes and different inner-ear loci are involved in cochlear homeostasis physiologically, to ensure the maintenance of an ion-balanced cochlear environment allowing a normal hair cell function. It has been hypothesized that a sudden loss of endocochlear potential, due to a rapid disruption of the inner ear fluid osmolality, could be responsible for a deterioration of the hearing function caused by damaged hair cells. The aim of this paper was to review the current literature and identify sources which might validate/fortify the hypothesis that inner ear electrolytic disorders have a role in the etiopathogenesis of SSNHL. The data in the literature underline the importance of ionic homeostasis in the inner ear, but they do not support a direct link between SSNHL and electrolyte disorders/imbalances. There is marginal evidence from otoacoustic emissions research that an indirect link might be present. © The Author(s) 2016.

  13. Right-ear advantage drives the link between olivocochlear efferent 'antimasking' and speech-in-noise listening benefits.

    Science.gov (United States)

    Bidelman, Gavin M; Bhagat, Shaum P

    2015-05-27

    The mammalian cochlea receives feedback from the brainstem medial olivocochlear (MOC) efferents, whose putative 'antimasking' function is to adjust cochlear amplification and enhance peripheral signal detection in adverse listening environments. Human studies have been inconsistent in demonstrating a clear connection between this corticofugal system and behavioral speech-in-noise (SIN) listening skills. To elucidate the role of brainstem efferent activity in SIN perception, we measured ear-specific contralateral suppression of transient-evoked otoacoustic emissions (OAEs), a proxy measure of MOC activation linked to auditory learning in noisy environments. We show that suppression of cochlear emissions is stronger with a more basal cochlear bias in the right ear compared with the left ear. Moreover, a strong negative correlation was observed between behavioral SIN performance and right-ear OAE suppression magnitudes, such that lower speech reception thresholds in noise were predicted by larger amounts of MOC-related activity. This brain-behavioral relation was not observed for left ear SIN perception. The rightward bias in contralateral MOC suppression of OAEs, coupled with the stronger association between physiological and perceptual measures, is consistent with left-hemisphere cerebral dominance for speech-language processing. We posit that corticofugal feedback from the left cerebral cortex through descending MOC projections sensitizes the right cochlea to signal-in-noise detection, facilitating figure-ground contrast and improving degraded speech analysis. Our findings demonstrate that SIN listening is at least partly driven by subcortical brain mechanisms; primitive stages of cochlear processing and brainstem MOC modulation of (right) inner ear mechanics play a critical role in dictating SIN understanding.

  14. Error Patterns Analysis of Hearing Aid and Cochlear Implant Users as a Function of Noise.

    Science.gov (United States)

    Chun, Hyungi; Ma, Sunmi; Han, Woojae; Chun, Youngmyoung

    2015-12-01

    Not all impaired listeners may have the same speech perception ability although they will have similar pure-tone threshold and configuration. For this reason, the present study analyzes error patterns in the hearing-impaired compared to normal hearing (NH) listeners as a function of signal-to-noise ratio (SNR). Forty-four adults participated: 10 listeners with NH, 20 hearing aids (HA) users and 14 cochlear implants (CI) users. The Korean standardized monosyllables were presented as the stimuli in quiet and three different SNRs. Total error patterns were classified into types of substitution, omission, addition, fail, and no response, using stacked bar plots. Total error percent for the three groups significantly increased as the SNRs decreased. For error pattern analysis, the NH group showed substitution errors dominantly regardless of the SNRs compared to the other groups. Both the HA and CI groups had substitution errors that declined, while no response errors appeared as the SNRs increased. The CI group was characterized by lower substitution and higher fail errors than did the HA group. Substitutions of initial and final phonemes in the HA and CI groups were limited by place of articulation errors. However, the HA group had missed consonant place cues, such as formant transitions and stop consonant bursts, whereas the CI group usually had limited confusions of nasal consonants with low frequency characteristics. Interestingly, all three groups showed /k/ addition in the final phoneme, a trend that magnified as noise increased. The HA and CI groups had their unique error patterns even though the aided thresholds of the two groups were similar. We expect that the results of this study will focus on high error patterns in auditory training of hearing-impaired listeners, resulting in reducing those errors and improving their speech perception ability.

  15. Changes in Tinnitus after Cochlear Implantation and Its Relation with Psychological Functioning

    NARCIS (Netherlands)

    Kloostra, Francka J. J.; Arnold, Rosemarie; Hofman, Rutger; Van Dijk, Pim

    2015-01-01

    This study retrospectively assessed the prevalence of tinnitus in cochlear implant patients and the changes after implantation in 212 patients implanted between 2000 and 2009. Patients were included at least 6 months after implantation and received 2 sets of questionnaires, one about the situation

  16. Speech Intelligibility and Psychosocial Functioning in Deaf Children and Teens with Cochlear Implants

    Science.gov (United States)

    Freeman, Valerie; Pisoni, David B.; Kronenberger, William G.; Castellanos, Irina

    2017-01-01

    Deaf children with cochlear implants (CIs) are at risk for psychosocial adjustment problems, possibly due to delayed speech-language skills. This study investigated associations between a core component of spoken-language ability--speech intelligibility--and the psychosocial development of prelingually deaf CI users. Audio-transcription measures…

  17. Characteristics of the Cochlear Symptoms and Functions in Meniere′s Disease

    Directory of Open Access Journals (Sweden)

    Yi Zhang

    2016-01-01

    Conclusions: Patients with definite Meniere′s disease always have a moderate to severe sensorineural hearing loss before diagnosis. Cochlear symptoms are the most common initial presentation. With the progression of the duration, the hearing impairment becomes more severe and the distribution of the audiometric pattern is distinctive between stages.

  18. Tbx1 and Brn4 regulate retinoic acid metabolic genes during cochlear morphogenesis

    Directory of Open Access Journals (Sweden)

    Braunstein Evan M

    2009-05-01

    Full Text Available Abstract Background In vertebrates, the inner ear is comprised of the cochlea and vestibular system, which develop from the otic vesicle. This process is regulated via inductive interactions from surrounding tissues. Tbx1, the gene responsible for velo-cardio-facial syndrome/DiGeorge syndrome in humans, is required for ear development in mice. Tbx1 is expressed in the otic epithelium and adjacent periotic mesenchyme (POM, and both of these domains are required for inner ear formation. To study the function of Tbx1 in the POM, we have conditionally inactivated Tbx1 in the mesoderm while keeping expression in the otic vesicle intact. Results Conditional mutants (TCre-KO displayed malformed inner ears, including a hypoplastic otic vesicle and a severely shortened cochlear duct, indicating that Tbx1 expression in the POM is necessary for proper inner ear formation. Expression of the mesenchyme marker Brn4 was also lost in the TCre-KO. Brn4-;Tbx1+/-embryos displayed defects in growth of the distal cochlea. To identify a potential signal from the POM to the otic epithelium, expression of retinoic acid (RA catabolizing genes was examined in both mutants. Cyp26a1 expression was altered in the TCre-KO, while Cyp26c1 showed reduced expression in both TCre-KO and Brn4-;Tbx1+/- embryos. Conclusion These results indicate that Tbx1 expression in the POM regulates cochlear outgrowth potentially via control of local retinoic acid activity.

  19. Swimmer's Ear

    Science.gov (United States)

    ... Body Mind Sexual Health Food & Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español Swimmer's Ear KidsHealth / ... español Otitis del nadador What Is Swimmer's Ear? Swimmer's ear is an infection of the ear canal . If you stick your ...

  20. Longitudinal functional performance among children with cochlear implants and disabilities: a prospective study using the Pediatric Evaluation of Disability Inventory.

    Science.gov (United States)

    Wiley, Susan; Meinzen-Derr, Jareen; Grether, Sandra; Choo, Daniel I; Hughes, Michelle L

    2012-05-01

    Functional outcomes are important in children with cochlear implants (CI) and additional disabilities as studies on auditory skill and speech/language development may not identify functional benefits from implantation. This study sought to measure functional performance skills of young children with developmental disabilities post-CI. Eight children with cognitive disabilities undergoing cochlear implantation were enrolled in a prospective study of language and functional abilities; 6 with 1 year follow-up were included in the analysis. Functional performance was measured using Pediatric Evaluation of Disability Inventory (PEDI), providing standardized (mean: 50) and scaled scores (range: 0-100) of functional domains: Self-Care, Mobility and Social Function. The PEDI was administered pre-implant, 6 and 12 months post-implantation along with language testing at the same intervals. All children had cognitive disability; 5 also had motor delay. The ages at CI ranged from 13.8 to 134 months. For functional abilities, children did not make significant changes in domain-specific standard scores over 1 year. Children made progress in scaled scores by 1-year post-implant. The largest increase for all domains occurred in the first 6 months (7-11.5 point increase). For language abilities, children made a median 5.5-month increase in receptive language age (p=0.06) and 5-month increase in expressive language age (p=0.03) in the first year post-CI with no change in language quotients. Receptive language level was significantly (pchildren with implants and disabilities using a standardized tool. Although our small group of complex children did not have an increase in standard scores (gap-closing trajectories), they made progress in skill development on scaled scores. Receptive language appears to play a key role in social functioning in this population. Functional assessments are informative for treatment planning and identifying specific areas to target intervention. Copyright

  1. Cochlear implantation in patients with bilateral cochlear trauma.

    Science.gov (United States)

    Serin, Gediz Murat; Derinsu, Ufuk; Sari, Murat; Gergin, Ozgül; Ciprut, Ayça; Akdaş, Ferda; Batman, Cağlar

    2010-01-01

    Temporal bone fracture, which involves the otic capsule, can lead to complete loss of auditory and vestibular functions, whereas the patients without fractures may experience profound sensorineural hearing loss due to cochlear concussion. Cochlear implant is indicated in profound sensorineural hearing loss due to cochlear trauma but who still have an intact auditory nerve. This is a retrospective review study. We report 5 cases of postlingually deafened patients caused by cochlear trauma, who underwent cochlear implantation. Preoperative and postoperative hearing performance will be presented. These patients are cochlear implanted after the cochlear trauma in our department between 2001 and 2006. All patients performed very well with their implants, obtained open-set speech understanding. They all became good telephone users after implantation. Their performance in speech understanding was comparable to standard postlingual adult patients implanted. Cochlear implantation is an effective aural rehabilitation in profound sensorineural hearing loss caused by temporal bone trauma. Preoperative temporal bone computed tomography, magnetic resonance imaging, and promontorium stimulation testing are necessary to make decision for the surgery and to determine the side to be implanted. Surgery could be challenging and complicated because of anatomical irregularity. Moreover, fibrosis and partial or total ossification within the cochlea must be expected. Copyright 2010. Published by Elsevier Inc.

  2. Cochlear Implants

    Science.gov (United States)

    A cochlear implant is a small, complex electronic device that can help to provide a sense of sound. People who are ... of-hearing can get help from them. The implant consists of two parts. One part sits on ...

  3. Assessment of Middle Ear Function during the Acoustic Reflex Using Laser-Doppler Vibrometry

    Science.gov (United States)

    2017-08-07

    probe stimulus. Using a surgical microscope (Zeiss POMI-1), the laser beam was focused on the light reflex near the umbo of the TM in the right ear...a surgical microscope and focused on the TM near the umbo. A continuous probe tone of varying frequencies was delivered to the ear measured by the...the Doppler Effect, sensing the frequency shift of back scattered light from a moving surface. Briefly, LDV works by comparing the frequency of the

  4. Deterioration of hearing in a cochlear implantee with relapsing polychondritis.

    Science.gov (United States)

    Patrizia, Mancini; Giuseppe, Attanasio; Marika, Viccaro; Roberto, Filipo

    2011-06-01

    We report on a rare case of cochlear implantation in a patient affected by relapsing polychondritis (RP), which over time induced cochlear fibrosis/ossification and deterioration of previously excellent hearing performance. The clinical course was determined by CT scan, electrophysiology, and speech perception data. We conclude that RP is a severe autoimmune connective disorder that can cause profound sensorineural hearing loss. Cochlear implantation in these patients can provide excellent performance. Continuation of therapy may improve prognosis, but relapses involving inner ear structures can determine fibrosis/ossification of the modiolus and interfere with cochlear implant use.

  5. Direct measurement flow resistance of cochlear aqueduct in guinea pigs

    NARCIS (Netherlands)

    Laurens-Thalen, EO; Wit, HP; Segenhout, JM; Albers, FWJ

    Objective - The cochlear aqueduct connects the scala tympani to the subarachnoid space and is the main pressure equalization canal for the inner ear. Increases in inner ear volume and pressure are thought to cause clinical symptoms such as vertigo, tinnitus and fluctuating hearing loss. In this

  6. Pierced Ears

    Science.gov (United States)

    ... how they do things is to watch another customer get his or her ears pierced. Without these precautions, you run the risk of getting infected ears. Metal Matters Your first earrings should have gold posts (the ...

  7. Usefulness of Electrical Auditory Brainstem Responses to Assess the Functionality of the Cochlear Nerve Using an Intracochlear Test Electrode.

    Science.gov (United States)

    Lassaletta, Luis; Polak, Marek; Huesers, Jan; Díaz-Gómez, Miguel; Calvino, Miryam; Varela-Nieto, Isabel; Gavilán, Javier

    2017-12-01

    To use an intracochlear test electrode to assess the integrity and the functionality of the auditory nerve in cochlear implant (CI) recipients and to compare electrical auditory brainstem responses (eABR) via the test electrode with the eABR responses with the CI. Otolaryngology department, tertiary referral hospital. Ten subjects (age at implantation 55 yr, range, 19-72) were subsequently implanted with a MED-EL CONCERTO CI on the side without any useful residual hearing. Following identification of the round window (RW), the test electrode was inserted in the cochlea previous to cochlear implantation. To assess the quality of an eABR waveform, scoring criteria from Walton et al. (2008) were chosen. The waveforms in each session were classified by detecting waves III and V by the algorithm and visual assessment of the waveform. Speech performance was evaluated with monosyllables, disyllables, and sentence recognition tests. It was possible to evoke electrical stimulation responses along with both the test electrode and the CI in all subjects. No significant differences in latencies or amplitudes after stimulation were found between the test electrode and the CI. All subjects obtained useful hearing with their CI and use their implants daily. The intracochlear test electrode may be suitable to test the integrity of the auditory nerve by recording eABR signals. This allows for further research on the status of the auditory nerve after tumor removal and correlation with auditory performance.

  8. Airplane Ear

    Science.gov (United States)

    ... your flight. If you're prone to severe airplane ear and must fly often, your doctor may surgically place tubes in your eardrums to aid fluid drainage, ventilate your middle ear, and equalize the ... prevent airplane ear These additional tips can help young children ...

  9. Ear Tubes

    Science.gov (United States)

    ... of the ear drum or eustachian tube, Down Syndrome, cleft palate, and barotrauma (injury to the middle ear caused by a reduction of air pressure, ... specialist) may be warranted if you or your child has experienced repeated ... fluid in the middle ear, barotrauma, or have an anatomic abnormality that ...

  10. Functional Near-Infrared Spectroscopy Brain Imaging Investigation of Phonological Awareness and Passage Comprehension Abilities in Adult Recipients of Cochlear Implants

    Science.gov (United States)

    Bisconti, Silvia; Shulkin, Masha; Hu, Xiaosu; Basura, Gregory J.; Kileny, Paul R.; Kovelman, Ioulia

    2016-01-01

    Purpose: The aim of this study was to examine how the brains of individuals with cochlear implants (CIs) respond to spoken language tasks that underlie successful language acquisition and processing. Method: During functional near-infrared spectroscopy imaging, CI recipients with hearing impairment (n = 10, mean age: 52.7 ± 17.3 years) and…

  11. COCHLEAR IMPLANTATION PREVALENCE IN ELDERLY

    Directory of Open Access Journals (Sweden)

    A. V. Starokha

    2014-01-01

    Full Text Available Current paper describes an experience of cochlear implantation in elderly. Cochlear implantation has become a widely accepted intervention in the treatment of individuals with severe-to-profound sensorineural hearing loss. Cochlear implants are now accepted as a standard of care to optimize hearing and subsequent speech development in children and adults with deafness. But cochlear implantation affects not only hearing abilities, speech perception and speech production; it also has an outstanding impact on the social life, activities and self-esteem of each patient. The aim of this study was to evaluate the cochlear implantation efficacy in elderly with severe to profound sensorineural hearing loss. There were 5 patients under our observation. Surgery was performed according to traditional posterior tympanotomy and cochleostomy for cochlear implant electrode insertion for all observed patients. The study was conducted in two stages: before speech processor’s activation and 3 months later. Pure tone free field audiometry was performed to each patient to assess the efficiency of cochlear implantation in dynamics. The aim of the study was also to evaluate quality of life in elderly with severe to profound sensorineural hearing loss after unilateral cochlear implantation. Each patient underwent questioning with 36 Item Short Form Health Survey (SF-36. SF-36 is a set of generic, coherent, and easily administered quality-of-life measures. The SF-36 consists of eight scaled scores, which are the weighted sums of the questions in their section. Each scale is directly transformed into a 0-100 scale on the assumption that each question carries equal weight. The eight sections are: physical functioning; physical role functioning; emotional role functioning; vitality; emotional well-being; social role functioning; bodily pain; general health perceptions. Our results demonstrate that cochlear implantation in elderly consistently improved quality of life

  12. Ear-canal wideband acoustic transfer functions of adults and two- to nine-month-old infants.

    Science.gov (United States)

    Werner, Lynne A; Levi, Ellen C; Keefe, Douglas H

    2010-10-01

    Wideband acoustic transfer functions (WATF) measured in the ear canal have been shown to be effective in the diagnosis of middle ear dysfunction in adults and in newborn infants. Although these measures would be diagnostically useful in older infants, normative data on a large number of older infants are lacking. The goal of this study was to provide such normative data. The WATF of 458 infants aged 2 to 9 mos and of 210 adults were obtained. Wideband reactance (X), resistance (R), and energy reflectance (ER) were measured in third-octave bands between 250 and 8000 Hz. The effects of age and gender on the WATF were examined, and the WATF in the left and right ears were compared. Test-retest reliability was assessed, and the relationship between the 226-Hz tympanogram and the WATF was examined. The results agreed well with previous reports testing fewer subjects, which documented age-related change in these measures during infancy and between infancy and adulthood. Test-retest correlations within third octaves were 0.5 to 0.7 at best, but did not vary systematically with age. Infants' test-retest absolute differences within third octaves for R and ER were similar to those of adults. The shape of the WATF on retest was highly repeatable, and the shapes of the WATF in the ears of the same individual were qualitatively similar. The wideband impedance results were not different in the left and right ears, but ER was slightly, but significantly, lower in the left ear than that in the right ear. Resistance and reactance magnitude were greater for females than males, but there was no effect of gender on ER. Infants whose 226-Hz tympanogram indicated reduced peak admittance (Types As and B) had greater resistance and reactance magnitude than those with normal peak admittance (Types A and C), but no tympanometry group differences were evident in ER. Age-graded norms are essential to the successful clinical application of WATF. However, the effects of gender and laterality on

  13. Spatiotemporal expression patterns of clusterin in the mouse inner ear.

    Science.gov (United States)

    Lee, Seokwon; Shin, Jeong-Oh; Sagong, Borum; Kim, Un-Kyung; Bok, Jinwoong

    2017-10-01

    Clusterin (CLU) is an extracellular chaperone protein that is implicated in diverse physiological and pathophysiological cellular processes. CLU expression is upregulated in response to cellular stress and under certain conditions, such as neurodegenerative disease and cancer. CLU primarily functions as a chaperone that exerts cytoprotective effects by removing cellular debris and misfolded proteins and also acts as a signaling molecule that regulates pro-survival pathways. Deafness is caused by genetic factors and various extrinsic insults, including ototoxic drugs, exposure to loud sounds and aging. Considering its cytoprotectivity, CLU may also mediate cellular defense mechanisms against hearing loss due to cellular stresses. To understand the function of CLU in the inner ear, we analyze CLU expression patterns in the mouse inner ear during development and in the adult stage. Results of quantitative real-time polymerase chain reaction analysis showed that Clu mRNA levels in the inner ear were increased during embryogenesis and were constantly expressed in the adult. Detailed spatial expression patterns of Clu both in the mRNA and protein levels were analyzed throughout various developmental stages via in situ hybridization and immunofluorescence staining. Clu expression was found in specific domains of developing inner ear starting from the otocyst stage, mainly adjacent to the prosensory domain of the cochlear epithelium. In the mature inner ear, Clu expression was observed in Deiter's cells and pillar cells of the organ of Corti, outer sulcus and in basal cells of the stria vascularis in the cochlea. These specific spatiotemporal expression patterns suggest the possible roles of CLU in inner ear development and in maintaining proper hearing function.

  14. Modeling microstructure of incudostapedial joint and the effect on cochlear input

    Science.gov (United States)

    Gan, Rong Z.; Wang, Xuelin

    2015-12-01

    The incudostapedial joint (ISJ) connects the incus to stapes in human ear and plays an important role for sound transmission from the tympanic membrane (TM) to cochlea. ISJ is a synovial joint composed of articular cartilage on the lenticular process and stapes head with the synovial fluid between them. However, there is no study on how the synovial ISJ affects the middle ear and cochlear functions. Recently, we have developed a 3-dimensinal finite element (FE) model of synovial ISJ and connected the model to our comprehensive FE model of the human ear. The motions of TM, stapes footplate, and basilar membrane and the pressures in scala vestibule and scala tympani were derived over frequencies and compared with experimental measurements. Results show that the synovial ISJ affects sound transmission into cochlea and the frequency-dependent viscoelastic behavior of ISJ provides protection for cochlea from high intensity sound.

  15. Clinical review of inner ear malformation

    International Nuclear Information System (INIS)

    Kokai, Hiromi; Oohashi, Masami; Ishikawa, Kazuo; Harada, Kouji; Hiratsuka, Hitoshi; Ogasawara, Makoto; Miyashita, Souji; Terayama, Yoshihiko

    2003-01-01

    We had 126 patients with inner ear malformation diagnosed with temporal bone computed tomography (CT) scans at Azabu Triology Hospital between 1996 and 2002. We classified cases of inner ear malformation according to Jackler et al. The incidence of inner ear malformation in our series was as follows; labyrinthine anomalies 61% (isolated lateral semicircular canal dysplasia 56%, compound semicircular canal dysplasia 4%, semicircular canal aplasia 1%), cochlear anomalies 24%, enlargement of the vestibular aqueduct 12%, narrow internal auditory canal 2%, complete labyrinthine aplasia 1%, enlargement of the cochlear aqueduct 0%. The most frequent anomaly was isolated lateral semicircular canal dysplasia. We did not detect any significant clinical features in this anomaly. There were 2 patients with cochlear anomalies who had past histories of meningitis. Some patients with enlargement of the vestibular aqueduct had frequent attacks of fluctuating hearing. Clinically it is important to detect patients with inner ear malformation such as cochlear anomalies and enlargement of the vestibular aqueduct usually accompanied by congenital sensorineural hearing loss. For patients with congenital sensorineural hearing loss, we recommend temporal bone CT scan. (author)

  16. The effect of thyroid autoantibody positivity on the functions of internal ear.

    Science.gov (United States)

    Gunes, Akif; Karakus, Mehmet Fatih; Telli, Tugba Akin; Gunes, Nurcan Akbas; Mutlu, Murad

    2017-11-01

    The objective of the study is to investigate if any significant difference exists in hearing thresholds and tympanometric examination results among patients whose thyroid antibody positivity was detected approximately 1 year or at least 5 years ago. Study population aged less than 40 years consisted of 17 patients who had thyroid antibody positivities for an average of 1 year (first group), 15 patients who were followed up for at least 5 years for thyroid antibody positivity (second group), and 18 volunteers (third group). Tympanometric examination results, stapes reflex, SRT, SD, and pure tone values were examined. When the second group and the third group were compared, significant results were obtained at hearing frequencies between 500 and 4000 Hz. When the first group and the third group were compared, only at 1000 Hz threshold significant results were obtained. During evaluation of hearing frequencies between 250 and 8000 Hz, significant results were not observed between the second group and the first group. When the first and the second groups were compared with the control group, significant results were obtained as for tympanometric examination findings and significant results were not observed between the second group and the first group. A significant difference was not detected as for the results of stapes reflex. Since thyroid antibody positivity affects the functions of internal ear, these patients should be more closely monitored. Since these effects become deeper in line with increased exposure to autoantibody positivity, variations in auditory responses should be more attentively monitored.

  17. Auditory function and hearing loss in children and adults with Williams syndrome: cochlear impairment in individuals with otherwise normal hearing.

    Science.gov (United States)

    Marler, Jeffrey A; Sitcovsky, Jessica L; Mervis, Carolyn B; Kistler, Doris J; Wightman, Frederic L

    2010-05-15

    Hearing loss is common in school-age individuals with Williams syndrome (WS) and extensive in adults. Prior studies with relatively small sample sizes suggest that hearing loss in WS has an early onset and may be progressive, yet the auditory phenotype and the scope of the hearing loss have not been adequately characterized. We used standard audiometric tools: Otoscopy, tympanometry, air-conduction (bone conduction when available) behavioral testing, and distortion product otoacoustic emissions (DPOAEs) to measure hearing sensitivity and outer hair cell function. We tested 81 individuals with WS aged 5.33-59.50 years. Sixty-three percent of the school-age and 92% of the adult participants had mild to moderately-severe hearing loss. The hearing loss in at least 50% was sensorineural. DPOAE testing corroborated behavioral results. Strikingly, 12 of 14 participants with hearing within normal limits bilaterally had 4,000-Hz DPOAE input/output (DPOAE IO) functions indicative of outer hair cell damage and impaired cochlear compression. Our results indicate that hearing loss is very common in WS. Furthermore, individuals with WS who have "normal" hearing as defined by behavioral thresholds may actually have sub-clinical impairments or undetected cochlear pathology. Our findings suggest outer hair cell dysfunction in otherwise normal hearing individuals. The DPOAE IO in this same group revealed growth functions typically seen in groups with noise-induced damage. Given this pattern of findings, individuals with WS may be at increased risk of noise-induced hearing loss. Recommendations regarding audiological testing for individuals with WS and accommodations for these individuals in both academic and nonacademic settings are provided.

  18. CT and MR imaging for pediatric cochlear implantation: emphasis on the relationship between the cochlear nerve canal and the cochlear nerve

    Energy Technology Data Exchange (ETDEWEB)

    Miyasaka, Mikiko; Nosaka, Shunsuke; Masaki, Hidekazu [National Center for Child Health and Development, Department of Radiology, Tokyo (Japan); Morimoto, Noriko; Taiji, Hidenobu [National Center for Child Health and Development, Department of Otolaryngology, Tokyo (Japan)

    2010-09-15

    Cochlear implantation has become an accepted treatment for deafness. As the frequency of cochlear implantation has increased, requests for images have also increased in the work-up for candidates. An absent cochlear nerve (CN) is a contraindication to cochlear implantation. Therefore, MRI is performed to evaluate the CN in patients with sensorineural hearing loss. Recently, some authors have reported the relationship between cochlear nerve canal (CNC) stenosis and CN hypoplasia. To review the relationship between CNC and CN. During a period of 78 months, 21 children (42 ears) with unilateral or bilateral sensorineural hearing loss underwent both HRCT and MRI of the cochlear nerve. We retrospectively reviewed two factors: the evaluation of inner ear malformations and the relationship between CNC stenosis and CN hypoplasia. Inner ear malformations were recognized in ten ears. The mean CNC diameter was approximately 2 mm (ranging from 0.6 to 2.7 mm). CN hypoplasia was seen in eight of the 42 ears; all eight were associated with CNC stenosis ({<=}1.5 mm). Of the 34 ears with normal CN, 32 had CNC >1.5 mm in diameter and the remaining two ears, with incomplete partition type I, had CNC stenosis. Children with CNC stenosis had a high incidence of CN hypoplasia. CNC stenosis ({<=}1.5 mm) suggests CN hypoplasia. On the other hand, CN hypoplasia was not seen in children with CNC diameter >1.5 mm. Therefore, we conclude that children with CNC stenosis or malformations on HRCT should receive MR imaging of the CN. (orig.)

  19. Interleaved Processors Improve Cochlear Implant Patients' Spectral Resolution.

    Science.gov (United States)

    Aronoff, Justin M; Stelmach, Julia; Padilla, Monica; Landsberger, David M

    2016-01-01

    Cochlear implant patients have difficulty in noisy environments, in part, because of channel interaction. Interleaving the signal by sending every other channel to the opposite ear has the potential to reduce channel interaction by increasing the space between channels in each ear. Interleaving still potentially provides the same amount of spectral information when the two ears are combined. Although this method has been successful in other populations such as hearing aid users, interleaving with cochlear implant patients has not yielded consistent benefits. This may be because perceptual misalignment between the two ears, and the spacing between stimulation locations must be taken into account before interleaving. Eight bilateral cochlear implant users were tested. After perceptually aligning the two ears, 12-channel maps were made that spanned the entire aligned portions of the array. Interleaved maps were created by removing every other channel from each ear. Participants' spectral resolution and localization abilities were measured with perceptually aligned processing strategies both with and without interleaving. There was a significant improvement in spectral resolution with interleaving. However, there was no significant effect of interleaving on localization abilities. The results indicate that interleaving can improve cochlear implant users' spectral resolution. However, it may be necessary to perceptually align the two ears and/or use relatively large spacing between stimulation locations.

  20. Student Musicians' Ear-Playing Ability as a Function of Vernacular Music Experiences

    Science.gov (United States)

    Woody, Robert H.; Lehmann, Andreas C.

    2010-01-01

    This study explored the differences in ear-playing ability between formal "classical" musicians and those with vernacular music experience (N = 24). Participants heard melodies and performed them back, either by singing or playing on their instruments. The authors tracked the number of times through the listen-then-perform cycle that each…

  1. [Otoacoustic emissions as cochlear function analyser in children with language disorders].

    Science.gov (United States)

    Aguilera-Tello, Silvia A; Gutiérrez-Farfán, Ileana; Chamlati-Aguirre, Laura E; Alatorre-Miguel, Efrén; Durand-Rivera, Alfredo

    2015-01-01

    Speech perception that takes place in the cochlea is involved in the process of language. The objective was to describe the findings in transient otoacoustic emissions in children with language problems before and after 6 months of speech therapy. There were 17 children with language problems between 3 and 6 years of age diagnosed with anarthric language delay (expressive and mixed language disorder). They underwent medical history, otoscopy, intelligence level testing, initial language test, tympanometry of 226Hz, audiometry and transient otoacoustic emission test. We evaluated the 17 patients again after 6 months of attending speech therapy. The percentage of overall reproducibility of transient otoacoustic emissions in both ears was adequate to perform frequency analysis. We found a statistically significant difference (P≤0.01) in the frequency of 1kHz reproducibility when comparing results before and after therapy in the right ear. There was a significant difference (P≤0.05) when comparing the results of audiometry at frequencies of 0.5, 1.5, 2, 4 and 8kHz in the right ear and a highly significant difference (P=0.001) in the frequency of 3kHz in the left ear. The analysis of sound through the cochlea is involved in the process of language acquisition. A poor processing of speech sounds in the peripheral system could result in poor processing at the central level. Consequently, it is important to consider our results when making a diagnosis and carrying out rehabilitation treatment in children with language disorders. Copyright © 2014 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

  2. Grhl1 deficiency affects inner ear development in zebrafish.

    Science.gov (United States)

    Liu, Fei; Yang, Fan; Wen, Danping; Xia, Wenjun; Hao, Lili; Hu, JiongJiong; Zong, Jie; Shen, Xiaofang; Ma, Jing; Jiang, Nan; Sun, Shaoyang; Zhang, Jin; Wang, Huijun; Wang, Xu; Ma, Zhaoxin; Ma, Duan

    2015-01-01

    Many genes that have been found to contribute to deafness are currently being studied. Some 87 non-syndromic hereditary deafness genes have been confirmed. Proteins associated with cochlear development have also been confirmed. Some of these proteins have important relationships with gap junctions (GJ) and tight junctions (TJ). However, the desmosome junction has received little attention due to controversy over whether it could be detected in the inner ear. GRHL1 is a conserved transcriptional regulator, and it is key to vertebrate desmosome formation. GRHL2 has been confirmed as a deafness gene at the DFNA28 locus. These two homologous proteins have similar sequences and functions. Here, a grhl1 down-regulated zebrafish model exhibited inner ear developmental malformations, including missing otoliths, disordered and abnormal numbers of hair cells in the inner ear and lateral line, and sound insensitivity. The mutant zebrafish swam in circles. Hair cell apoptosis was evident. Under electron microscopy, desmosomes in the otic sensory epithelium were found to be damaged. These defects were partially rescued by treatment with either GRHL1 or its target gene, DSG1. Collectively, these data are the first to indicate that grhl1 is important to the developing inner ear epithelia in zebrafish and that it acts via desmosome junction regulation.

  3. Cochlear Implants

    Science.gov (United States)

    ... For young children who are deaf or severely hard-of-hearing, using a cochlear implant while they are young exposes them to sounds during an optimal period to develop speech and language skills. Research has shown that when these children receive ...

  4. The candidate splicing factor Sfswap regulates growth and patterning of inner ear sensory organs.

    Directory of Open Access Journals (Sweden)

    Yalda Moayedi

    2014-01-01

    Full Text Available The Notch signaling pathway is thought to regulate multiple stages of inner ear development. Mutations in the Notch signaling pathway cause disruptions in the number and arrangement of hair cells and supporting cells in sensory regions of the ear. In this study we identify an insertional mutation in the mouse Sfswap gene, a putative splicing factor, that results in mice with vestibular and cochlear defects that are consistent with disrupted Notch signaling. Homozygous Sfswap mutants display hyperactivity and circling behavior consistent with vestibular defects, and significantly impaired hearing. The cochlea of newborn Sfswap mutant mice shows a significant reduction in outer hair cells and supporting cells and ectopic inner hair cells. This phenotype most closely resembles that seen in hypomorphic alleles of the Notch ligand Jagged1 (Jag1. We show that Jag1; Sfswap compound mutants have inner ear defects that are more severe than expected from simple additive effects of the single mutants, indicating a genetic interaction between Sfswap and Jag1. In addition, expression of genes involved in Notch signaling in the inner ear are reduced in Sfswap mutants. There is increased interest in how splicing affects inner ear development and function. Our work is one of the first studies to suggest that a putative splicing factor has specific effects on Notch signaling pathway members and inner ear development.

  5. Microanatomy of the cochlear hook

    Science.gov (United States)

    Kwan, Changyow Claire; Tan, Xiaodong; Stock, Stuart R.; Soriano, Carmen; Xiao, Xianghui; Richter, Claus-Peter

    2017-09-01

    Communication among humans occurs through coding and decoding of acoustic information. The inner ear or cochlea acts as a frequency analyzer and divides the acoustic signal into small frequency bands, which are processed at different sites along the cochlea. The mechano-electrical conversion is accomplished by the soft tissue structures in the cochlea. While the anatomy for most of the cochlea has been well described, a detailed description of the very high frequency and vulnerable cochlear hook region is missing. To study the cochlear hook, mice cochleae were imaged with synchrotron radiation and high-resolution reconstructions have been made from the tomographic scans. This is the first detailed description of the bony and soft tissues of the hook region of the mammalian cochlea.

  6. Expression and function of FGF10 in mammalian inner ear development

    Science.gov (United States)

    Pauley, Sarah; Wright, Tracy J.; Pirvola, Ulla; Ornitz, David; Beisel, Kirk; Fritzsch, Bernd

    2003-01-01

    We have investigated the expression of FGF10 during ear development and the effect of an FGF10 null mutation on ear development. Our in situ hybridization data reveal expression of FGF10 in all three canal crista sensory epithelia and the cochlea anlage as well as all sensory neurons at embryonic day 11.5 (E11.5). Older embryos (E18.5) displayed strong graded expression in all sensory epithelia. FGF10 null mutants show complete agenesis of the posterior canal crista and the posterior canal. The posterior canal sensory neurons form initially and project rather normally by E11.5, but they disappear within 2 days. FGF10 null mutants have no posterior canal system at E18.5. In addition, these mutants have deformations of the anterior and horizontal cristae, reduced formation of the anterior and horizontal canals, as well as altered position of the remaining sensory epithelia with respect to the utricle. Hair cells form but some have defects in their cilia formation. No defects were detected in the organ of Corti at the cellular level. Together these data suggest that FGF10 plays a major role in ear morphogenesis. Most of these data are consistent with earlier findings on a null mutation in FGFR2b, one of FGF10's main receptors. Copyright 2003 Wiley-Liss, Inc.

  7. Cross-Modal Functional Reorganization of Visual and Auditory Cortex in Adult Cochlear Implant Users Identified with fNIRS.

    Science.gov (United States)

    Chen, Ling-Chia; Sandmann, Pascale; Thorne, Jeremy D; Bleichner, Martin G; Debener, Stefan

    2016-01-01

    Cochlear implant (CI) users show higher auditory-evoked activations in visual cortex and higher visual-evoked activation in auditory cortex compared to normal hearing (NH) controls, reflecting functional reorganization of both visual and auditory modalities. Visual-evoked activation in auditory cortex is a maladaptive functional reorganization whereas auditory-evoked activation in visual cortex is beneficial for speech recognition in CI users. We investigated their joint influence on CI users' speech recognition, by testing 20 postlingually deafened CI users and 20 NH controls with functional near-infrared spectroscopy (fNIRS). Optodes were placed over occipital and temporal areas to measure visual and auditory responses when presenting visual checkerboard and auditory word stimuli. Higher cross-modal activations were confirmed in both auditory and visual cortex for CI users compared to NH controls, demonstrating that functional reorganization of both auditory and visual cortex can be identified with fNIRS. Additionally, the combined reorganization of auditory and visual cortex was found to be associated with speech recognition performance. Speech performance was good as long as the beneficial auditory-evoked activation in visual cortex was higher than the visual-evoked activation in the auditory cortex. These results indicate the importance of considering cross-modal activations in both visual and auditory cortex for potential clinical outcome estimation.

  8. Cross-Modal Functional Reorganization of Visual and Auditory Cortex in Adult Cochlear Implant Users Identified with fNIRS

    Directory of Open Access Journals (Sweden)

    Ling-Chia Chen

    2016-01-01

    Full Text Available Cochlear implant (CI users show higher auditory-evoked activations in visual cortex and higher visual-evoked activation in auditory cortex compared to normal hearing (NH controls, reflecting functional reorganization of both visual and auditory modalities. Visual-evoked activation in auditory cortex is a maladaptive functional reorganization whereas auditory-evoked activation in visual cortex is beneficial for speech recognition in CI users. We investigated their joint influence on CI users’ speech recognition, by testing 20 postlingually deafened CI users and 20 NH controls with functional near-infrared spectroscopy (fNIRS. Optodes were placed over occipital and temporal areas to measure visual and auditory responses when presenting visual checkerboard and auditory word stimuli. Higher cross-modal activations were confirmed in both auditory and visual cortex for CI users compared to NH controls, demonstrating that functional reorganization of both auditory and visual cortex can be identified with fNIRS. Additionally, the combined reorganization of auditory and visual cortex was found to be associated with speech recognition performance. Speech performance was good as long as the beneficial auditory-evoked activation in visual cortex was higher than the visual-evoked activation in the auditory cortex. These results indicate the importance of considering cross-modal activations in both visual and auditory cortex for potential clinical outcome estimation.

  9. A new entropy function for feature extraction with the refined scores as a classifier for the unconstrained ear verification

    Directory of Open Access Journals (Sweden)

    Mamta Bansal

    2017-05-01

    Full Text Available For high end security like surveillance there is a need for a robust system capable of verifying a person under the unconstrained conditions. This paper presents the ear based verification system using a new entropy function that changes not only the information gain function but also the information source values. This entropy function displays peculiar characteristics such as splitting into two modes. Two types of entropy features: Effective Gaussian Information source value and Effective Exponential Information source value functions are derived using the entropy function. To classify the entropy features we have devised refined scores (RS method that refines the scores generated using the Euclidean distance. The experimental results vindicate the superiority of proposed method over literature.

  10. Wideband acoustic immittance for assessing middle ear functioning for preterm neonates in the neonatal intensive care unit

    Directory of Open Access Journals (Sweden)

    Nandel Gouws

    2017-06-01

    Full Text Available Background: The primary aim of newborn hearing screening is to detect permanent hearing loss. Because otoacoustic emissions (OAEs and automated auditory brainstem response (AABR are sensitive to hearing loss, they are often used as screening tools. On the other hand, false-positive results are most often because of transient outer- and middle ear conditions. Wideband acoustic immittance (WAI, which includes physical measures known as reflectance and absorbance, has shown potential for accurate assessment of middle ear function in young infants. Objective: The main objective of this study was to determine the feasibility of WAI as a diagnostic tool for assessing middle ear functioning in preterm neonates in the neonatal intensive care unit (NICU designed for premature and ill neonates. A further objective was to indicate the difference between the reflectance values of tones and click stimuli. Method: Fifty-six at-risk neonates (30 male and 26 female, with a mean age at testing of 35.6 weeks (range: 32–37 weeks and a standard deviation of 1.6 from three private hospitals, who passed both the distortion product otoacoustic emission (DPOAE and AABR tests, were evaluated prior to discharge from the NICU. Neonates who presented with abnormal DPOAE and AABR results were excluded from the study. WAI was measured by using chirp and tone stimuli. In addition to reflectance, the reflectance area index (RAI values were calculated. Results: Both tone and chirp stimuli indicated high-power reflectance values below a frequency of 1.5 kHz. Median reflectance reached a minimum of 0.67 at 1 kHz – 2 kHz but increased to 0.7 below 1 kHz and 0.72 above 2 kHz for the tone stimuli. For chirp stimuli, the median reflectance reached a minimum of 0.51 at 1 kHz – 2 kHz but increased to 0.68 below 1 kHz and decreased to 0.5 above 2 kHz. A comparison between the present study and previous studies on WAI indicated a substantial variability across all frequency ranges

  11. Cochlear implant

    Science.gov (United States)

    ... made up of a microphone/receiver, a speech processor, and an antenna. This part of the implant ... ear. This sound is sent to a speech processor, which is most often connected to the microphone ...

  12. Using Balance Function to Screen for Vestibular Impairment in Children With Sensorineural Hearing Loss and Cochlear Implants.

    Science.gov (United States)

    Oyewumi, Modupe; Wolter, Nikolaus E; Heon, Elise; Gordon, Karen A; Papsin, Blake C; Cushing, Sharon L

    2016-08-01

    1) To determine if bilateral vestibular dysfunction can be predicted by performance on standardized balance tasks in children with sensorineural hearing loss (SNHL) and cochlear implants (CI). 2) To provide clinical recommendations for screening for vestibular impairment in children with SNHL. Retrospective cohort study. Tertiary care pediatric implant center. Pediatric patients (4.8-18.6 years) with profound SNHL using CIs. Vestibular end-organ (horizontal canal and otoliths), and balance assessment. Comparison of balance skills, measured by the Bruininks Oseretsky Test of Motor Proficiency II (BOT-2), was performed between two groups of children with SNHL and CI: 1) total bilateral vestibular loss (TBVL) (n = 45), and 2) normal bilateral vestibular function (n = 20). Sensitivity, specificity, and suitability of each task as a screening tool for the detection of TBVL were assessed. Balance as measured by the BOT-2 balance subtest was significantly poorer in children with TBVL then those with normal vestibular function (p balance function using one of the BOT-2 balance subtest tasks, one-foot standing eyes closed, is able to identify children at risk of TBVL with excellent sensitivity and specificity and should be used to screen for TBVL in all children presenting with SNHL.

  13. Sirviendo a los estudiantes sordos que tienen Los implantes cocleares. Hoja de consejos de PEPNet (Serving Deaf Students Who Have Cochlear Implants. PEPNet Tipsheet)

    Science.gov (United States)

    Clark, Catherine

    2010-01-01

    This version of "Serving Deaf Students Who Have Cochlear Implants. PEPNet Tipsheet," written in Spanish, describes how cochlear implants (CIs) work. CIs are complex electronic devices surgically implanted under the skin behind the ear. These devices utilize electrodes placed in the inner ear (the cochlea) to stimulate the auditory nerve of…

  14. Cochlear Implant Rate Pitch and Melody Perception as a Function of Place and Number of Electrodes

    Science.gov (United States)

    Marimuthu, Vijay; Mannell, Robert

    2016-01-01

    Six Nucleus cochlear implant recipients participated in a study investigating the effect of place of stimulation on melody perception using rate-pitch cues. Each stimulus was a pulse train delivered on either a single electrode or multiple electrodes sequentially. Four spatial stimulation patterns were used: a single apical electrode, a single mid electrode, a pair of electrodes (apical and mid), and 11 electrodes (from apical to mid). Within one block of trials, all stimuli had the same spatial stimulation pattern, with pulse rate varying from 131 to 262 pps. An additional pulse rate range of 262 to 523 pps was tested with the single-electrode stimuli. Two experimental procedures were used: note ranking; and a modified melodies test with backwards and warp modification. In each trial of the modified melodies test, a familiar melody and a version with modified pitch were presented (in random order), and the subject’s task was to select the unmodified melody. There were no significant differences in performance for stimulation on 1, 2, or 11 electrodes, implying that recipients were unable to combine temporal information from different places in the cochlea to give a stronger pitch cue. No advantage of apical electrodes was found: at the lower pulse rates, there were no significant differences between electrodes; and at the higher pulse rates, scores on the apical electrode dropped more than those on the mid electrode. PMID:27094028

  15. Pattern of hearing loss in a rat model of cochlear implantation trauma.

    Science.gov (United States)

    Eshraghi, Adrien A; Polak, Marek; He, Jiao; Telischi, Fred F; Balkany, Thomas J; Van De Water, Thomas R

    2005-05-01

    Trauma caused by cochlear implant electrode insertion is attributable to the combination of direct physical trauma and the delayed cell death of oxidative stress-injured auditory sensory cells. Histologic evaluation of cochlear implant electrode trauma has demonstrated that the extent of sensory cell losses is proportional to the degree of injury. However, the impact of delayed oxidative stress within injured cochlear tissues and the progressive loss of injured hair cells by way of apoptosis are at present unknown. Laboratory rats were evaluated for hearing acuity before and after electrode insertion, before and after round window membrane incision only. Hearing was measured before trauma or incision and over the next 7 days. Objective measurements of hearing function were distortion products of otoacoustic emissions (DPOAEs) in the frequency range of 2 to 32 kHz and tone-burst (i.e., 4-32 kHz) evoked auditory brain stem responses (ABRs). For the experimental cochleae, there were progressive increases in ABR thresholds and decreases in ABR amplitudes. The amplitude of the DPOAEs in the experimental cochleae also showed progressive decreases. For the contralateral control and round window membrane surgical control ears, there were no significant changes in either DPOAE or ABR thresholds. These results document a progressive loss of hearing acuity postimplantation and strongly suggest that electrode insertion trauma generated oxidative stress within injured cochlear tissues.

  16. Perspectives for the treatment of sensorineural hearing loss by cellular regeneration of the inner ear.

    Science.gov (United States)

    Almeida-Branco, Mario S; Cabrera, Sonia; Lopez-Escamez, Jose A

    2015-01-01

    Sensorineural hearing loss is a caused by the loss of the cochlear hair cells with the consequent deafferentation of spiral ganglion neurons. Humans do not show endogenous cellular regeneration in the inner ear and there is no exogenous therapy that allows the replacement of the damaged hair cells. Currently, treatment is based on the use of hearing aids and cochlear implants that present different outcomes, some difficulties in auditory discrimination and a limited useful life. More advanced technology is hindered by the functional capacity of the remaining spiral ganglion neurons. The latest advances with stem cell therapy and cellular reprogramming have developed several possibilities to induce endogenous regeneration or stem cell transplantation to replace damaged inner ear hair cells and restore hearing function. With further knowledge of the cellular and molecular biology of the inner ear and its embryonic development, it will be possible to use induced stem cells as in vitro models of disease and as replacement cellular therapy. Investigation in this area is focused on generating cellular therapy with clinical use for the treatment of profound sensorineural hearing loss. Copyright © 2014 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

  17. Meningitis as cochlear implant complication

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    Kosanović Rade

    2009-01-01

    Full Text Available Over the last several decades, cochlear implantation has been fully proven as the treatment for profound hearing losses. The direct electrical stimulation of the spiral ganglion hair cells through the electrode inserted in the cochlear scala tympani is the essence of the cochlear implant (CI functioning. Modern technological development has introduced unexpected technical quality possibilities of the device itself, as well as coding strategies, which further enable improved patients' rehabilitation results. Nevertheless, in spite of cochlear implantation becoming a routine surgical procedure, which has been changing lives of thousands of profoundly deaf adults and children, it has possible complications. Though rare, these complications could lead to severe, even fatal consequences. Bacterial meningitis represents one of the most severe postoperative complications. In this article, our five-year experience with cochlear implantation is shown, compared to other, much bigger, experiences. Despite severity and a potentially fatal outcome of meningitis, it has rarely been seen, and the precise connection between surgical procedure and this complication is not yet clear. Do cochlear implants increase the risk of bacterial meningitis? Are deafness-associated factors predisposing the bacterial meningitis occurrence, independently from the implant? These are the questions that the Centers for Disease Control and Prevention (CDC, the Food and Drug Administration (FDA and the CI surgeons have been facing, as well as manufacturers and patients with their families.

  18. Quantitative polarized light microscopy of unstained mammalian cochlear sections

    Science.gov (United States)

    Kalwani, Neil M.; Ong, Cheng Ai; Lysaght, Andrew C.; Haward, Simon J.; McKinley, Gareth H.; Stankovic, Konstantina M.

    2013-02-01

    Hearing loss is the most common sensory deficit in the world, and most frequently it originates in the inner ear. Yet, the inner ear has been difficult to access for diagnosis because of its small size, delicate nature, complex three-dimensional anatomy, and encasement in the densest bone in the body. Evolving optical methods are promising to afford cellular diagnosis of pathologic changes in the inner ear. To appropriately interpret results from these emerging technologies, it is important to characterize optical properties of cochlear tissues. Here, we focus on that characterization using quantitative polarized light microscopy (qPLM) applied to unstained cochlear sections of the mouse, a common animal model of human hearing loss. We find that the most birefringent cochlear materials are collagen fibrils and myelin. Retardance of the otic capsule, the spiral ligament, and the basilar membrane are substantially higher than that of other cochlear structures. Retardance of the spiral ligament and the basilar membrane decrease from the cochlear base to the apex, compared with the more uniform retardance of other structures. The intricate structural details revealed by qPLM of unstained cochlear sections ex vivo strongly motivate future application of polarization-sensitive optical coherence tomography to human cochlea in vivo.

  19. Cochlear implants: system design, integration, and evaluation.

    Science.gov (United States)

    Zeng, Fan-Gang; Rebscher, Stephen; Harrison, William; Sun, Xiaoan; Feng, Haihong

    2008-01-01

    As the most successful neural prosthesis, cochlear implants have provided partial hearing to more than 120000 persons worldwide; half of which being pediatric users who are able to develop nearly normal language. Biomedical engineers have played a central role in the design, integration and evaluation of the cochlear implant system, but the overall success is a result of collaborative work with physiologists, psychologists, physicians, educators, and entrepreneurs. This review presents broad yet in-depth academic and industrial perspectives on the underlying research and ongoing development of cochlear implants. The introduction accounts for major events and advances in cochlear implants, including dynamic interplays among engineers, scientists, physicians, and policy makers. The review takes a system approach to address critical issues in cochlear implant research and development. First, the cochlear implant system design and specifications are laid out. Second, the design goals, principles, and methods of the subsystem components are identified from the external speech processor and radio frequency transmission link to the internal receiver, stimulator and electrode arrays. Third, system integration and functional evaluation are presented with respect to safety, reliability, and challenges facing the present and future cochlear implant designers and users. Finally, issues beyond cochlear implants are discussed to address treatment options for the entire spectrum of hearing impairment as well as to use the cochlear implant as a model to design and evaluate other similar neural prostheses such as vestibular and retinal implants.

  20. Adjustments of the amplitude mapping function: Sensitivity of cochlear implant users and effects on subjective preference and speech recognition.

    Science.gov (United States)

    Theelen-van den Hoek, Femke L; Boymans, Monique; van Dijk, Bas; Dreschler, Wouter A

    2016-11-01

    In sound processors of cochlear implant (CI) users, input sound signals are analysed in multiple frequency channels. The amplitude mapping function (AMF) is the output compression function dictating the conversion from (acoustical) channel output levels to (electrical) current levels used for electrode stimulation. This study focused on the detectability of AMF adjustments by CI users and the effects of detectable AMF adjustments on subjective preference and performance. Just noticeable differences (JNDs) for AMF settings were measured for pre-processed sentences at 60 dB SPL in quiet and noise. Three AMF settings, ranging twice the JND, were used during a take-home trial period of 12 days. Subjective ratings were collected and speech recognition in quiet and noise was measured. JND measurements: 17 CI users. Field experiment: 15 CI users. JNDs for AMF settings varied among subjects and were similar in quiet and noise. A steeper AMF in the lower part was advantageous for speech recognition in quiet at soft levels. Subjective ratings showed limited agreement with speech recognition, both in quiet and noise. CI users may benefit from different AMF settings in different listening situations regarding subjective preference and speech perception, especially for speech in quiet.

  1. The Hearing Outcomes of Cochlear Implantation in Waardenburg Syndrome.

    Science.gov (United States)

    Koyama, Hajime; Kashio, Akinori; Sakata, Aki; Tsutsumiuchi, Katsuhiro; Matsumoto, Yu; Karino, Shotaro; Kakigi, Akinobu; Iwasaki, Shinichi; Yamasoba, Tatsuya

    2016-01-01

    Objectives. This study aimed to determine the feasibility of cochlear implantation for sensorineural hearing loss in patients with Waardenburg syndrome. Method. A retrospective chart review was performed on patients who underwent cochlear implantation at the University of Tokyo Hospital. Clinical classification, genetic mutation, clinical course, preoperative hearing threshold, high-resolution computed tomography of the temporal bone, and postoperative hearing outcome were assessed. Result. Five children with Waardenburg syndrome underwent cochlear implantation. The average age at implantation was 2 years 11 months (ranging from 1 year 9 months to 6 years 3 months). Four patients had congenital profound hearing loss and one patient had progressive hearing loss. Two patients had an inner ear malformation of cochlear incomplete partition type 2. No surgical complication or difficulty was seen in any patient. All patients showed good hearing outcome postoperatively. Conclusion. Cochlear implantation could be a good treatment option for Waardenburg syndrome.

  2. The Hearing Outcomes of Cochlear Implantation in Waardenburg Syndrome

    Directory of Open Access Journals (Sweden)

    Hajime Koyama

    2016-01-01

    Full Text Available Objectives. This study aimed to determine the feasibility of cochlear implantation for sensorineural hearing loss in patients with Waardenburg syndrome. Method. A retrospective chart review was performed on patients who underwent cochlear implantation at the University of Tokyo Hospital. Clinical classification, genetic mutation, clinical course, preoperative hearing threshold, high-resolution computed tomography of the temporal bone, and postoperative hearing outcome were assessed. Result. Five children with Waardenburg syndrome underwent cochlear implantation. The average age at implantation was 2 years 11 months (ranging from 1 year 9 months to 6 years 3 months. Four patients had congenital profound hearing loss and one patient had progressive hearing loss. Two patients had an inner ear malformation of cochlear incomplete partition type 2. No surgical complication or difficulty was seen in any patient. All patients showed good hearing outcome postoperatively. Conclusion. Cochlear implantation could be a good treatment option for Waardenburg syndrome.

  3. The relationship between binaural benefit and difference in unilateral speech recognition performance for bilateral cochlear implant users.

    Science.gov (United States)

    Yoon, Yang-Soo; Li, Yongxin; Kang, Hou-Yong; Fu, Qian-Jie

    2011-08-01

    The full benefit of bilateral cochlear implants may depend on the unilateral performance with each device, the speech materials, processing ability of the user, and/or the listening environment. In this study, bilateral and unilateral speech performances were evaluated in terms of recognition of phonemes and sentences presented in quiet or in noise. Speech recognition was measured for unilateral left, unilateral right, and bilateral listening conditions; speech and noise were presented at 0° azimuth. The 'binaural benefit' was defined as the difference between bilateral performance and unilateral performance with the better ear. Nine adults with bilateral cochlear implants participated. On average, results showed a greater binaural benefit in noise than in quiet for all speech tests. More importantly, the binaural benefit was greater when unilateral performance was similar across ears. As the difference in unilateral performance between ears increased, the binaural advantage decreased; this functional relationship was observed across the different speech materials and noise levels even though there was substantial intra- and inter-subject variability. The results indicate that subjects who show symmetry in speech recognition performance between implanted ears in general show a large binaural benefit.

  4. Ear Problems

    Science.gov (United States)

    ... Infants and Children Chest Pain, Acute Chest Pain, Chronic Cold and Flu Cough Diarrhea Ear Problems Elimination Problems Elimination Problems in Infants and Children Eye Problems Facial Swelling Feeding Problems in Infants ...

  5. Ear examination

    Science.gov (United States)

    ... to the side, or the child's head may rest against an adult's chest. Older children and adults may sit with the head tilted toward the shoulder opposite the ear being examined. The provider will ...

  6. Role of prostaglandin E receptor subtypes EP2 and EP4 in autocrine and paracrine functions of vascular endothelial growth factor in the inner ear

    Directory of Open Access Journals (Sweden)

    Hamaguchi Kiyomi

    2010-03-01

    Full Text Available Abstract Background The physiological effects of prostaglandin E1 (PGE1 and prostaglandin E2 (PGE2 are mediated by the prostaglandin E receptor subtypes EP1, EP2, EP3, and EP4, and the respective agonists have been purified. PGE1 and PGE2 can increase the production of vascular endothelial growth factor (VEGF, particularly through EP2 and EP4. The biological effects of VEGF are mediated by the phosphotyrosine kinase receptors fms-related tyrosine kinase-1 (Flt-1 and fetal liver kinase-1 (Flk-1. Here we examined the effects of EP2 and EP4 agonists on the production of VEGF proteins and VEGF messenger RNAs (mRNAs in the inner ear, using an enzyme-linked immunosorbent assay and the real-time quantitative reverse transcription-polymerase chain reaction, respectively. We also examined the localization of EP2, VEGF, Flt-1, and Flk-1 in the cochlea by immunohistochemistry. Results The expression of EP2 occurred in the cochlea, and the local application of an EP2 or EP4 agonist increased VEGF protein and VEGF mRNA levels in the inner ear. Furthermore, the intensity of the VEGF immunoreactivity in the spiral ganglion appeared to be increased by the local EP2 or EP4 agonist treatment. Immunoreactivity for Flt-1, and Flk-1 was found in the cochlear sensory epithelium, spiral ganglion, spiral ligament, and stria vascularis. Conclusions These findings demonstrate that EP2 and EP4 agonists stimulate VEGF production in the inner ear, particularly in the spiral ganglions. Moreover, the Flt-1 and Flk-1 expression observed in the present study suggests that VEGF has autocrine and paracrine actions in the cochlea. Thus, EP2 and EP4 might be involved in the mechanisms underlying the therapeutic effects of PGE1 on acute sensorineural hearing loss via VEGF production.

  7. Role of prostaglandin E receptor subtypes EP2 and EP4 in autocrine and paracrine functions of vascular endothelial growth factor in the inner ear.

    Science.gov (United States)

    Hori, Ryusuke; Nakagawa, Takayuki; Yamamoto, Norio; Hamaguchi, Kiyomi; Ito, Juichi

    2010-03-11

    The physiological effects of prostaglandin E1 (PGE1) and prostaglandin E2 (PGE2) are mediated by the prostaglandin E receptor subtypes EP1, EP2, EP3, and EP4, and the respective agonists have been purified. PGE1 and PGE2 can increase the production of vascular endothelial growth factor (VEGF), particularly through EP2 and EP4. The biological effects of VEGF are mediated by the phosphotyrosine kinase receptors fms-related tyrosine kinase-1 (Flt-1) and fetal liver kinase-1 (Flk-1). Here we examined the effects of EP2 and EP4 agonists on the production of VEGF proteins and VEGF messenger RNAs (mRNAs) in the inner ear, using an enzyme-linked immunosorbent assay and the real-time quantitative reverse transcription-polymerase chain reaction, respectively. We also examined the localization of EP2, VEGF, Flt-1, and Flk-1 in the cochlea by immunohistochemistry. The expression of EP2 occurred in the cochlea, and the local application of an EP2 or EP4 agonist increased VEGF protein and VEGF mRNA levels in the inner ear. Furthermore, the intensity of the VEGF immunoreactivity in the spiral ganglion appeared to be increased by the local EP2 or EP4 agonist treatment. Immunoreactivity for Flt-1, and Flk-1 was found in the cochlear sensory epithelium, spiral ganglion, spiral ligament, and stria vascularis. These findings demonstrate that EP2 and EP4 agonists stimulate VEGF production in the inner ear, particularly in the spiral ganglions. Moreover, the Flt-1 and Flk-1 expression observed in the present study suggests that VEGF has autocrine and paracrine actions in the cochlea. Thus, EP2 and EP4 might be involved in the mechanisms underlying the therapeutic effects of PGE1 on acute sensorineural hearing loss via VEGF production.

  8. Multislice spiral computed tomography imaging in congenital inner ear malformations.

    Science.gov (United States)

    Ma, Hui; Han, Ping; Liang, Bo; Tian, Zhi-liang; Lei, Zi-qiao; Kong, Wei-jia; Feng, Gan-sheng

    2008-01-01

    The purpose of this study is to evaluate the usefulness of multislice spiral computed tomography (CT) in the diagnosis of congenital inner ear malformations. Forty-four patients with sensorineural hearing loss were examined on a Somatom Sensation 16 (Siemens) CT scanner. The 3-dimensional reconstructions and multiplanar reformation (MPR) were performed using the volume-rendering technique (VRT) on the workstation. Of the 44 patients examined for this study, 25 patients were found to be normal and 19 patients (36 ears) were diagnosed with congenital inner ear malformations. Of the malformations, the axial, MPR, and VRT images can all display the site and degree in 33 of the ears. Volume-rendering technique images were superior to the axial images in displaying the malformations in 3 ears with small lateral semicircular canal malformations. The common malformations were Michel deformity (1 ear), common cavity deformity (3 ears), incomplete partition I (3 ears), incomplete partition II (Mondini deformity) (5 ears), vestibular and semicircular canal malformations (14 ears), enlarged vestibular aqueduct (16 ears, 6 of which had other malformations), and internal auditory canal malformation (8 ears, all accompanied by other malformations). Multislice spiral CT allows a comprehensively assessment of various congenital inner ear malformations through high-quality MPR and VRT reconstructions. Volume-rendering technique images can display the site and degree of the malformation 3-dimensionally and intuitionisticly. This is very useful to the cochlear implantation.

  9. Cochlear Implant

    Directory of Open Access Journals (Sweden)

    Mehrnaz Karimi

    1993-03-01

    Full Text Available People with profound hearing loss are not able to use some kinds of conventional amplifiers due to the nature of their loss. In these people, hearing sense is stimulated only when the auditory nerve is activated via electrical stimulation. This stimulation is possible through cochlear implant. In fact, for the deaf people who have good mental health and can not use surgical and medical treatment and also can not benefit from air and bone conduction hearing aids, this device is used if they have normal central auditory system. The basic parts of the device included: Microphone, speech processor, transmitter, stimulator and receiver, and electrode array.

  10. Cochlear Implant

    Directory of Open Access Journals (Sweden)

    Mehrnaz Karimi

    1992-04-01

    Full Text Available People with profound hearing loss are not able to use some kinds of conventional amplifiers due to the nature of their loss . In these people, hearing sense is stimulated only when the auditory nerve is activated via electrical stimulation. This stimulation is possible through cochlear implant. In fact, for the deaf people who have good mental health and can not use surgical and medical treatment and also can not benefit from air and bone conduction hearing aids, this device is used if they have normal central auditory system. The basic parts of the device included: Microphone, speech processor, transmitter, stimulator and receiver, and electrode array.

  11. Investigation of the vestibular aqueduct and the cochlear aqueduct by temboral bone CT scan

    International Nuclear Information System (INIS)

    Shimizu, Ryuichi; Kamei, Tamio; Ito, Fumihide

    1984-01-01

    The visualization of the vestibular aqueduct and the cochlear aqueduct was investigated by temporal bone CT scan. The vestibular aqueduct was visualized in horizontal CT sections of 70.0% of normal ears, 61.5% of ears with chronic otitis media, 58.3% of ears with combined hearing impairment, 66.7% of ears in cases of sudden deafness, 70.8% of ears of patients with sensorineural hearing impairment without sudden deafness, 71.4% of cases of vertigo without hearing impairment and 12.5% of both diseased and contralateral ears of patients with Meniere's disease. Only in Meniere's disease was the vestibular aqueduct less visible in the diseased than in the normal ear (P<0.01). The cochlear aqueduct was visible in coronal sections of 50.0% of normal ears, 76.9% of those with chronic otitis media, 58.3% of those with combined hearing impairment, 66.7% of those with sudden deafness 41.7% of those with sensorineural hearing impairment without sudden deafness, 50.0% of the diseased ears of patients with Meniere's disease, 37.5% of the contralateral ears of those with Meniere's disease and 64.3% of those with vertigo without hearing impairment. Although the cochlear aqueduct was thus highly demonstrable in patients with chronic otitis media or sudden deafness, the difference between the percentage of visualization in these diseased and in normal ears was not statistically significant. (author)

  12. Is All Human Hearing Cochlear?

    Directory of Open Access Journals (Sweden)

    Seyede Faranak Emami

    2013-01-01

    Full Text Available The objective of this cross-sectional study was to investigate the possibility that the saccule may contribute to human hearing. The forty participants included twenty healthy people and twenty other subjects selected from patients who presented with benign paroxysmal positional vertigo to Audiology Department of Hazrat Rasoul Akram hospital (Tehran, Iran. Assessments comprised of audiological evaluations, cervical vestibular evoked myogenic potentials (cVEMPs, recognition of spoken phonemes in white noise (Rsp in wn, and auditory brainstem response to 500 Hz tone burst (ABR500 HZ. Twenty affected ears with decreased vestibular excitability as detected by abnormal cVEMPs revealed decreased scores of Rsp in wn and abnormal findings of ABR500 HZ. Both unaffected and normal ears had normal results. Multiple comparisons of mean values of cVEMPs and ABR500 HZ between three groups were significant (P<0.05, ANOVA. The correlation between RSP in wn and p13 latencies was significant. The peak-to-peak amplitudes showed significant correlation to RSP in wn. The correlation between RSP in wn and the latencies of n23 was significant. In high-level of noisy competing situations, healthy human saccular sensation can mediate the detection of low frequencies and possibly help in cochlear hearing for frequency and intensity discrimination. So, all human hearing is not cochlear.

  13. Characteristics and application of inner ear CT in 20 cases of sensorineural hearing loss in children.

    Science.gov (United States)

    Huo, Liang; Wang, Hua

    2012-12-01

    This study shows that a number of children with sensorineural hearing loss (SNHL) have inner ear malformations demonstrated by multi-slice spiral computed tomography (MSCT). MSCT allows a comprehensive assessment of various congenital inner ear malformations through high quality multiplanar reformation (MPR) and can display the site and degree of the malformation three-dimensionally and intuitively. This is very useful for cochlear implantation. To evaluate the feasibility and usability of MSCT in pediatric SNHL with inner ear malformations. Sixty-five patients were diagnosed with SNHL by brainstem auditory evoked response (BAER). Inner ear MSCT scan and coronal MPR reconstruction were performed in all cases. This study demonstrated 20 cases (33 ears) with inner ear malformations, which included 10 ears with cochlear malformations, 7 with vestibular malformations, 5 with semicircular canal malformations, 8 with internal auditory canal (IAC) malformations, and 15 with vestibular malformations. Cochlear malformations included one ear with Michel deformity, two ears with common cavity deformity, one with cochlear aplasia, one with hypoplastic cochlea, two with incomplete partition type I, and three with incomplete partition type II (Mondini deformity).

  14. Rare case of bilateral aural atresia and cochlear dysplasia: when cochlear implantation is not the answer.

    Science.gov (United States)

    Svrakic, Maja

    2018-02-17

    Reports of patients with concurrent middle and inner ear anomalies are rare. These patients present a surgical challenge for cochlear implantation. The surgical risk must be weighed against the predicted benefit of the patient's hearing outcome and subsequent development of speech and language as well as their quality of life. Thirteen-year-old boy presented to the Otology clinic for auditory rehabilitation options. He has mild developmental delay, is non-verbal and communicates via American Sign Language. He was born with bilateral aural atresia and never wore amplification. On exam he has grade 1 microtia and complete ear canal atresia bilaterally. His behavioural hearing test shows profound sensorineural hearing loss of both ears. The computed tomography scan shows bilateral underdeveloped and completely opacified mastoid and middle ear, complete bony atresia of the ear canals, and an under-partitioned cochlea with poorly defined modiolus, among other abnormalities. The patient and his family were counselled on the available options as well as the need for any further studies. Counselling of patient and family. While there have been reports in the literature of performing cochlear implantations in patients with a concurrent atresia and cochlear dysplasia, these were patients whose degree of inner ear anomalies was relatively minor and their prognosis of a good audiological outcome was favourable. The presented case is that of a patient for whom the surgical approach to the cochlea alone would be difficult. More importantly, his quality of life would not significantly improve in light of the predicted limited hearing and language development outcomes, given the severity of his inner ear abnormalities, limited communication abilities, prolonged period of deafness and developmental delays.

  15. In vivo areal modulus of elasticity estimation of the human tympanic membrane system: modelling of middle ear mechanical function in normal young and aged ears

    DEFF Research Database (Denmark)

    Gaihede, Michael Lyhne; Donghua, Liao; Gregersen, H.

    2007-01-01

    The quasi-static elastic properties of the tympanic membrane system can be described by the areal modulus of elasticity determined by a middle ear model. The response of the tympanic membrane to quasi-static pressure changes is determined by its elastic properties. Several clinical problems are r...... finite element analyses. In vivo estimates of Young's modulus in this study were a factor 2-3 smaller than previously found in vitro. No significant age-related differences were found in the elastic properties as expressed by the areal modulus.......The quasi-static elastic properties of the tympanic membrane system can be described by the areal modulus of elasticity determined by a middle ear model. The response of the tympanic membrane to quasi-static pressure changes is determined by its elastic properties. Several clinical problems...... are related to these, but studies are few and mostly not comparable. The elastic properties of membranes can be described by the areal modulus, and these may also be susceptible to age-related changes reflected by changes in the areal modulus. The areal modulus is determined by the relationship between...

  16. Change of guinea pig inner ear pressure by square wave middle ear cavity pressure variation

    NARCIS (Netherlands)

    Feijen, RA; Segenhout, JM; Albers, FWJ; Wit, HP

    The inner ear fluid pressure of guinea pigs was measured during square wave middle ear cavity pressure variation. Time constants were derived for the slopes of the inner ear pressure recovery curves after middle ear pressure change. A "single exponential" function did not fit well and therefore more

  17. Music Perception with Cochlear Implants: A Review

    Science.gov (United States)

    McDermott, Hugh J.

    2004-01-01

    The acceptance of cochlear implantation as an effective and safe treatment for deafness has increased steadily over the past quarter century. The earliest devices were the first implanted prostheses found to be successful in compensating partially for lost sensory function by direct electrical stimulation of nerves. Initially, the main intention was to provide limited auditory sensations to people with profound or total sensorineural hearing impairment in both ears. Although the first cochlear implants aimed to provide patients with little more than awareness of environmental sounds and some cues to assist visual speech-reading, the technology has advanced rapidly. Currently, most people with modern cochlear implant systems can understand speech using the device alone, at least in favorable listening conditions. In recent years, an increasing research effort has been directed towards implant users’ perception of nonspeech sounds, especially music. This paper reviews that research, discusses the published experimental results in terms of both psychophysical observations and device function, and concludes with some practical suggestions about how perception of music might be enhanced for implant recipients in the future. The most significant findings of past research are: (1) On average, implant users perceive rhythm about as well as listeners with normal hearing; (2) Even with technically sophisticated multiple-channel sound processors, recognition of melodies, especially without rhythmic or verbal cues, is poor, with performance at little better than chance levels for many implant users; (3) Perception of timbre, which is usually evaluated by experimental procedures that require subjects to identify musical instrument sounds, is generally unsatisfactory; (4) Implant users tend to rate the quality of musical sounds as less pleasant than listeners with normal hearing; (5) Auditory training programs that have been devised specifically to provide implant users with

  18. Preoperative vestibular assessment protocol of cochlear implant surgery: an analytical descriptive study

    Directory of Open Access Journals (Sweden)

    Roseli Saraiva Moreira Bittar

    Full Text Available Abstract Introduction: Cochlear implants are undeniably an effective method for the recovery of hearing function in patients with hearing loss. Objective: To describe the preoperative vestibular assessment protocol in subjects who will be submitted to cochlear implants. Methods: Our institutional protocol provides the vestibular diagnosis through six simple tests: Romberg and Fukuda tests, assessment for spontaneous nystagmus, Head Impulse Test, evaluation for Head Shaking Nystagmus and caloric test. Results: 21 patients were evaluated with a mean age of 42.75 ± 14.38 years. Only 28% of the sample had all normal test results. The presence of asymmetric vestibular information was documented through the caloric test in 32% of the sample and spontaneous nystagmus was an important clue for the diagnosis. Bilateral vestibular areflexia was present in four subjects, unilateral arreflexia in three and bilateral hyporeflexia in two. The Head Impulse Test was a significant indicator for the diagnosis of areflexia in the tested ear (p = 0.0001. The sensitized Romberg test using a foam pad was able to diagnose severe vestibular function impairment (p = 0.003. Conclusion: The six clinical tests were able to identify the presence or absence of vestibular function and function asymmetry between the ears of the same individual.

  19. Speech Perception in Tones and Noise via Cochlear Implants Reveals Influence of Spectral Resolution on Temporal Processing

    Directory of Open Access Journals (Sweden)

    Andrew J. Oxenham

    2014-09-01

    Full Text Available Under normal conditions, human speech is remarkably robust to degradation by noise and other distortions. However, people with hearing loss, including those with cochlear implants, often experience great difficulty in understanding speech in noisy environments. Recent work with normal-hearing listeners has shown that the amplitude fluctuations inherent in noise contribute strongly to the masking of speech. In contrast, this study shows that speech perception via a cochlear implant is unaffected by the inherent temporal fluctuations of noise. This qualitative difference between acoustic and electric auditory perception does not seem to be due to differences in underlying temporal acuity but can instead be explained by the poorer spectral resolution of cochlear implants, relative to the normally functioning ear, which leads to an effective smoothing of the inherent temporal-envelope fluctuations of noise. The outcome suggests an unexpected trade-off between the detrimental effects of poorer spectral resolution and the beneficial effects of a smoother noise temporal envelope. This trade-off provides an explanation for the long-standing puzzle of why strong correlations between speech understanding and spectral resolution have remained elusive. The results also provide a potential explanation for why cochlear-implant users and hearing-impaired listeners exhibit reduced or absent masking release when large and relatively slow temporal fluctuations are introduced in noise maskers. The multitone maskers used here may provide an effective new diagnostic tool for assessing functional hearing loss and reduced spectral resolution.

  20. [HRCT imaging characterized of congenital abnormalities of the inner ear in 45 cases].

    Science.gov (United States)

    Wang, Jinling; Meng, Meijuan; Huan, Yi; Zhang, Jinsong

    2003-10-01

    To explore the high resolution CT (HRCT) image characterized of congenital abnormalities of the inner ear(CAIE), and its value in the diagnosis and treatment of CAIE. The clinic data and axial HRCT scans of CAIE in 45 cases were analyzed. In 45 CAIE patients, most of them were frequently associated with slowly progressive sensorineural hearing loss in childhood, 15 ears were fluctuating hearing loss. Seventeen ears were unilateral semicircular canal paralysis. HRCT showed that Michel type 3 cases(4 ears), Mondini type 25 cases(39 ears). Large vestibular aqueduct malformation not associated with anomalies of inner ears 13 cases(23 ears), anomalies of internal auditory canal 4 cases (5 ears). Thirteen ears were associated with outer and middle ear malformation. HRCT image has the important value in the diagnosis and treatment of CAIE, especially for the excerpt of indication of cochlear implantation.

  1. Functional results of Vibrant Soundbridge middle ear implants in conductive and mixed hearing losses.

    Science.gov (United States)

    Bernardeschi, Daniele; Hoffman, Caroline; Benchaa, Tarek; Labassi, Samia; Beliaeff, Michel; Sterkers, Olivier; Grayeli, Alexis Bozorg

    2011-01-01

    Our purpose was to evaluate the results of Vibrant Soundbridge (VSB) in conductive or mixed hearing loss. Twenty-five adult patients (29 ears) with a mixed or conductive hearing loss and various etiologies were included in this retrospective study. The preoperative ipsilateral pure tone average was 71 ± 3.0 dB, and the average bone conduction threshold was 42 ± 2.8 dB (n = 29). The transducer was placed on the long apophysis of the incus (n = 16), in the round window (n = 10) or on the stapes (n = 3). No complications were noted. The bone conduction threshold remained unchanged. VSB was activated in all cases. The postoperative pure tone average without VSB was 63 ± 3.9 dB (n = 24) and with VSB in free-field condition 24 ± 2.1 dB (n = 22). VSB is safe and efficacious for auditory rehabilitation in conductive and mixed hearing losses. Copyright © 2011 S. Karger AG, Basel.

  2. Gentamicin Pharmacokinetics in the Chicken Inner Ear

    OpenAIRE

    Bunting, Eric C.; Park, Debra L.; Durham, Dianne; Girod, Douglas A.

    2004-01-01

    Avians have the unique ability to regenerate cochlear hair cells that are lost due to ototoxins or excessive noise. Many methodological techniques are available to damage the hair cells for subsequent scientific study. A recent method utilizes topical application of an ototoxic drug to the round window membrane. The current study examines the pharmacokinetics of gentamicin in the inner ear of chickens following topical application to the round window membrane or a single system...

  3. In vivo areal modulus of elasticity estimation of the human tympanic membrane system: modelling of middle ear mechanical function in normal young and aged ears

    International Nuclear Information System (INIS)

    Gaihede, Michael; Liao Donghua; Gregersen, Hans

    2007-01-01

    The quasi-static elastic properties of the tympanic membrane system can be described by the areal modulus of elasticity determined by a middle ear model. The response of the tympanic membrane to quasi-static pressure changes is determined by its elastic properties. Several clinical problems are related to these, but studies are few and mostly not comparable. The elastic properties of membranes can be described by the areal modulus, and these may also be susceptible to age-related changes reflected by changes in the areal modulus. The areal modulus is determined by the relationship between membrane tension and change of the surface area relative to the undeformed surface area. A middle ear model determined the tension-strain relationship in vivo based on data from experimental pressure-volume deformations of the human tympanic membrane system. The areal modulus was determined in both a younger (n = 10) and an older (n = 10) group of normal subjects. The areal modulus for lateral and medial displacement of the tympanic membrane system was smaller in the older group (mean = 0.686 and 0.828 kN m -1 , respectively) compared to the younger group (mean = 1.066 and 1.206 kN m -1 , respectively), though not significantly (2p = 0.10 and 0.11, respectively). Based on the model the areal modulus was established describing the summated elastic properties of the tympanic membrane system. Future model improvements include exact determination of the tympanic membrane area accounting for its shape via 3D finite element analyses. In vivo estimates of Young's modulus in this study were a factor 2-3 smaller than previously found in vitro. No significant age-related differences were found in the elastic properties as expressed by the areal modulus

  4. Changes in microvascular permeability of the middle ear mucosa following the occulsion of the eustachian tube of rabbits. The functional investigation using radioisotope

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Yasutaka

    1988-12-01

    Serial changes in submucosal microvascular permeability of the middle ear and the response to histamine after occlusion of the eustachian tube were functionally investigated using radioisotope in rabbits with experimentally induced otitis media with effusion. Tritium water was administered through intravenous injection and transference of tritium water into the middle ear cavity was measured by radioactivity of the middle ear perfusate. Morphological changes were concurrently examined for comparison. Vascular permeability, as measured one, 7, and 14 days after occlusion of the eustachian tube, increased with time. A histological study showed an edematous hypertrophy of the submucosal tissue of the middle ear, suggesting a noticeable increase in microvascular permeability. The response of the middle ear mucosa to histamine, which was added to the fluid for perfusion, gradually decreased after occlusion of the eustachian tube, although the effect of histamine tended to persist for a long time, irrespective of the amount of administration. The results indicated that the mucosal membrane of the middle ear has a noticeable permeability at least up to 14 days after occlusion, and that histamine may be responsible for the increase of submucosal microvascular permeability not only in the normal middle ear cavity but also in otitis media with effusion which results in the persistance of the disease. The presence of factors permeable to the blood, other than histamine, caused microvascular peameability to increase, probably resulting in chronic or irreversible inflammation. This may be explained by markedly proliferative or parenchymatous connective tissues observed 7 and l0 weeks after occlusion. It should be noted that surgical treatment be performed as early as possible in the case of otitis media with effusion. (Namekawa, K) 80 refs.

  5. Cochlear Patency After Transmastoid Labyrinthectomy for Ménière's Syndrome.

    Science.gov (United States)

    Sargent, Eric W; Liao, Eric; Gonda, Roger L

    2016-08-01

    Labyrinthectomy is considered the "gold standard" in the treatment of intractable vertigo attacks because of Ménière's Disease (MD) but sacrifices all residual hearing. Interest in auditory rehabilitation has lead to cochlear implantation in some patients. Concern remains that the cochlear lumen may fill with tissue or bone after surgery. This study sought to determine the incidence of obliteration of the cochlea after transmastoid labyrinthectomy. Retrospective observational study. Tertiary referral center. Eighteen patients with intractable vertigo from MD who underwent surgery. Transmastoid labyrinthectomy between 2008 and 2013. Cochleas were imaged with unenhanced, heavily T2-weighted magnetic resonance imaging (MRI). Presence of symmetrical cochlear fluid signals on MRI. There was no loss of fluid signal in the cochleas of operated ear compared with the contralateral, unoperated ear in any subject an average of 3 years (standard deviation [SD]: 1.2) after surgery. Five of 18 patients had the vestibule blocked with bone wax at the time of surgery. Blocking the vestibule with bone wax did not change the cochlear fluid signal. The risk of cochlear obstruction after labyrinthectomy for MD is very low. The significance of this finding is that patients with MD who undergo labyrinthectomy will likely remain candidates for cochlear implantation in the labyrinthectomized ear long after surgery if this becomes needed. Immediate cochlear implantation or placement of a cochlear lumen keeper during labyrinthectomy for MD is probably not necessary.

  6. Pure-Tone Masking Patterns for Monopolar and Phantom Electrical Stimulation in Cochlear Implants.

    Science.gov (United States)

    Saoji, Aniket A; Koka, Kanthaiah; Litvak, Leonid M; Finley, Charles C

    Monopolar stimulation of the most apical electrode produces the lowest pitch sensation in cochlear implants clinically. A phantom electrode that uses out-of-phase electrical stimulation between the most apical and the neighboring basal electrode can produce a lower pitch sensation than that associated with the most apical electrode. However, because of the absence of contacts beyond the apical tip of the array, the ability to assess the spread of electrical excitation associated with phantom stimulation is limited in the typical cochlear implant subject with no residual hearing. In the present study, the spread of electrical excitation associated with monopolar and phantom stimulation of the most apical electrode was assessed using electrical masking of acoustic thresholds in cochlear implant subjects with residual, low-frequency, acoustic hearing. Eight subjects with an Advanced Bionics cochlear implant and residual hearing in the implanted ear participated in this study (nine ears in total). Unmasked and masked thresholds for acoustic pure tones were measured at 125, 250, 500, 750, 1000, and 2000 Hz in the presence of monopolar and phantom electrode stimulation presented at the apical-most end of the array. The current compensation for phantom electrode stimulation was fixed at 50%. The two electrical maskers were loudness balanced. Differences between the unmasked and masked acoustic thresholds can be attributed to (1) the electrical stimulus-induced interference in the transduction/conduction of the acoustic signal through cochlear periphery and the auditory nerve and/or (2) masking at the level of the central auditory system. The results show a significant elevation in pure-tone thresholds in the presence of the monopolar and phantom electrical maskers. The unmasked thresholds were subtracted from the masked thresholds to derive masking patterns as a function of the acoustic probe frequency. The masking patterns show that phantom stimulation was able to

  7. Ear Infections

    Science.gov (United States)

    ... can cause your child’s eardrum to rupture or pop, leaving a hole in the ear. The initial pop hurts, but actually relieves the pressure and pain. ... turns up the volume of the TV or music, is not responding to softer sounds or is ...

  8. Infectious complications of pediatric cochlear implants are highly influenced by otitis media.

    Science.gov (United States)

    Vila, Peter M; Ghogomu, Nsangou T; Odom-John, Audrey R; Hullar, Timothy E; Hirose, Keiko

    2017-06-01

    Determine the incidence of ear infections in cochlear implant patients, evaluate the contribution of otitis media to complications, describe the bacteriology of otitis media in the cochlear implant population, the treatment provided at our center, and the long term outcome. Data collected included age at implantation, history of otitis media or ear tubes, etiology of hearing loss, inner ear anatomy, postoperative infections, time to infection, route of antibiotic administration, and interventions for infections. Categories of infection were acute otitis media, otitis media with effusion, tube otorrhea, meningitis, scalp cellulitis, and infection at the implant site. Middle ear infections were diagnosed in 37% of implanted ears. Extension of middle ear infections into the implant site occurred in 2.8% of all implants (n = 16). Of the 16 infected devices, 10 were successfully treated with antibiotic therapy and did not require explantation. The retained implant group and explanted group both included some middle ear microbes such as Haemophilus influenzae and Streptococcus pneumoniae, as well as skin flora such as Staphylococcus aureus. Otitis media in pediatric cochlear implant patients is a common event and usually does not lead to complications of the cochlear implant. However, when the ear infection spreads to the scalp and the implant site, it is still possible to eliminate the infection using antibiotic therapy, particularly when treatment is directed to the specific organism that is recovered from the infected space and the duration and route of antibiotic treatment is carefully considered. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Long-term asymmetric hearing affects cochlear implantation outcomes differently in adults with pre- and postlingual hearing loss.

    Science.gov (United States)

    Boisvert, Isabelle; McMahon, Catherine M; Dowell, Richard C; Lyxell, Björn

    2015-01-01

    In many countries, a single cochlear implant is offered as a treatment for a bilateral hearing loss. In cases where there is asymmetry in the amount of sound deprivation between the ears, there is a dilemma in choosing which ear should be implanted. In many clinics, the choice of ear has been guided by an assumption that the reorganisation of the auditory pathways caused by longer duration of deafness in one ear is associated with poorer implantation outcomes for that ear. This assumption, however, is mainly derived from studies of early childhood deafness. This study compared outcomes following implantation of the better or poorer ear in cases of long-term hearing asymmetries. Audiological records of 146 adults with bilateral hearing loss using a single hearing aid were reviewed. The unaided ear had 15 to 72 years of unaided severe to profound hearing loss before unilateral cochlear implantation. 98 received the implant in their long-term sound-deprived ear. A multiple regression analysis was conducted to assess the relative contribution of potential predictors to speech recognition performance after implantation. Duration of bilateral significant hearing loss and the presence of a prelingual hearing loss explained the majority of variance in speech recognition performance following cochlear implantation. For participants with postlingual hearing loss, similar outcomes were obtained by implanting either ear. With prelingual hearing loss, poorer outcomes were obtained when implanting the long-term sound-deprived ear, but the duration of the sound deprivation in the implanted ear did not reliably predict outcomes. Contrary to an apparent clinical consensus, duration of sound deprivation in one ear has limited value in predicting speech recognition outcomes of cochlear implantation in that ear. Outcomes of cochlear implantation are more closely related to the period of time for which the brain is deprived of auditory stimulation from both ears.

  10. Children With Cochlear Implants and Their Parents: Relations Between Parenting Style and Children's Social-Emotional Functioning.

    Science.gov (United States)

    Ketelaar, Lizet; Wiefferink, Carin H; Frijns, Johan H M; Rieffe, Carolien

    Parenting a child who has a severe or profound hearing loss can be challenging and at times stressful, and might cause parents to use more adverse parenting styles compared with parents of hearing children. Parenting styles are known to impact children's social-emotional development. Children with a severe to profound hearing loss may be more reliant on their parents in terms of their social-emotional development when compared with their hearing peers who typically have greater opportunities to interact with and learn from others outside their family environment. Identifying the impact which parenting styles pertain on the social-emotional development of children who have cochlear implants (CIs) could help advance these children's well-being. Therefore, the authors compared parenting styles of parents with hearing children and of parents with children who have a CI, and examined the relations between parenting styles and two key aspects of children's social-emotional functioning: emotion regulation and empathy. Ninety-two hearing parents and their children (aged 1 to 5 years old), who were either hearing (n = 46) or had a CI (n = 46), participated in this cross-sectional study. Parents completed questionnaires concerning their parenting styles (i.e., positive, negative and uninvolved), and regarding the extent to which their children expressed negative emotions (i.e., anger and sadness) and empathy. Furthermore, an emotion-regulation task measuring negative emotionality was administered to the children. No differences in reported parenting styles were observed between parents of hearing children and parents of children with a CI. In addition, negative and uninvolved parenting styles were related to higher levels of negative emotionality in both groups of children. No relation was found between positive parenting and children's social-emotional functioning. Hearing status did not moderate these relationships. Language mediated the relationship between parenting

  11. In vitro and in vivo evaluation of a hydrogel reservoir as a continuous drug delivery system for inner ear treatment.

    Directory of Open Access Journals (Sweden)

    Mareike Hütten

    Full Text Available Fibrous tissue growth and loss of residual hearing after cochlear implantation can be reduced by application of the glucocorticoid dexamethasone-21-phosphate-disodium-salt (DEX. To date, sustained delivery of this agent to the cochlea using a number of pharmaceutical technologies has not been entirely successful. In this study we examine a novel way of continuous local drug application into the inner ear using a refillable hydrogel functionalized silicone reservoir. A PEG-based hydrogel made of reactive NCO-sP(EO-stat-PO prepolymers was evaluated as a drug conveying and delivery system in vitro and in vivo. Encapsulating the free form hydrogel into a silicone tube with a small opening for the drug diffusion resulted in delayed drug release but unaffected diffusion of DEX through the gel compared to the free form hydrogel. Additionally, controlled DEX release over several weeks could be demonstrated using the hydrogel filled reservoir. Using a guinea-pig cochlear trauma model the reservoir delivery of DEX significantly protected residual hearing and reduced fibrosis. As well as being used as a device in its own right or in combination with cochlear implants, the hydrogel-filled reservoir represents a new drug delivery system that feasibly could be replenished with therapeutic agents to provide sustained treatment of the inner ear.

  12. Cosmetic ear surgery

    Science.gov (United States)

    Otoplasty; Ear pinning; Ear surgery - cosmetic; Ear reshaping; Pinnaplasty ... Cosmetic ear surgery may be done in the surgeon's office, an outpatient clinic, or a hospital. It can be performed under ...

  13. Establishing the standard method of cochlear implant in Rongchang pig.

    Science.gov (United States)

    Chen, Wei; Yi, Haijin; Zhang, Liang; Ji, Fei; Yuan, Shuolong; Zhang, Yue; Ren, Lili; Li, Jianan; Chen, Lei; Guo, Weiwei; Yang, Shiming

    2017-05-01

    In this investigation, a large mammal, Rongchang pigs were used to successfully establish a research platform for cochlear implant study on the routine use of it in clinic. The aim of this study was to establish a standard method of cochlear implant in a large mammal-pig. Rongchang pigs were selected, then divided into two groups: normal-hearing group (Mitf +/+) and mutation group with hearing loss (Mitf -/-). Cochlear implants were used and ABR and EABR were recorded. The implanted electrodes were observed by X-ray and HE stains. The success with cochlear implant and the best electrode position could be defined in all animals, the coiling of the cochlea reached 1.5-1.75 turns. Immediately after the operation of cochlear implants, the ABR threshold of the operated ear (right) could not be derived for each frequency at 120 dB SPL. Moreover, 7 days after surgery, the low-frequency ABR threshold of the operated ear (right) could be derived partly at 100 dB SPL, but the high-frequency ABR threshold could not be derived at 120 dB SPL. Immediately or 1 week after cochlear implants, the EABR threshold was 90 CL in the Mitf +/+ group. This was obviously lower than the 190 CL in the Mitf -/- group.

  14. The Effect of Ethnicity on Wideband Absorbance of Neonates with Healthy Middle Ear Functions in Malaysia: A Preliminary Study.

    Science.gov (United States)

    Wali, Hamzah A; Mazlan, Rafidah

    2018-01-01

    Although ethnicity effect on wideband absorbance (WBA) findings was evident for adults, its effect on neonates has not been established yet. This study aimed to investigate the influence of ethnicity on WBA measured at 0 daPa from neonates with healthy middle ear functions. Participants were 99 normal, healthy, full-term newborn babies with chronological age between 11 and 128 hours of age (mean=46.73, standard deviation=26.36). A cross-sectional study design was used to measure WBA at 16 one-third octave frequency points from 99 neonates comprising of three ethnic groups: Malays (n=58), Chinese (n=13) and Indians (n=28). A total of 165 ears (83.3%) that passed a battery of tests involving distortion product otoacoustic emissions, 1 kHz tympanometry and acoustic stapedial reflex were further tested using WBA. Moreover, body size measurements were recorded from each participant. The Malays and Indians neonates showed almost identical WBA response across the frequency range while the Chinese babies showed lower absorbance values between 1.25 kHz and 5 kHz. However, the differences observed in WBA between the three ethnic groups were not statistically significant ( p =0.23). Additionally, there were no statistically significant difference in birth weight, height and head circumference among the three ethnic groups. This study showed that Malays, Chinese and Indians neonates were not significantly different in their WBA responses. In conclusion, to apply for the ethnic-specific norms is not warranted when testing neonates from population constitute of these three ethnicities.

  15. Suggestions for a Guideline for Cochlear Implantation in CHARGE Syndrome

    NARCIS (Netherlands)

    Vesseur, Annemarie; Free, Rolien; Langereis, Margreet; Snels, Chantal; Snik, Ad; Ravenswaaij-Arts, van Conny; Mylanus, Emmanuel

    2016-01-01

    Objective:Identifying aspects for establishing cochlear implantation guidelines for patients with ocular coloboma, heart defects, atresia of the choanae, retardation (of growth and/or of development), genital anomalies, and ear anomalies (CHARGE) syndrome (CS).Study Design:Explorative retrospective

  16. The Notch ligand JAG1 is required for sensory progenitor development in the mammalian inner ear.

    Directory of Open Access Journals (Sweden)

    Amy E Kiernan

    2006-01-01

    Full Text Available In mammals, six separate sensory regions in the inner ear are essential for hearing and balance function. Each sensory region is made up of hair cells, which are the sensory cells, and their associated supporting cells, both arising from a common progenitor. Little is known about the molecular mechanisms that govern the development of these sensory organs. Notch signaling plays a pivotal role in the differentiation of hair cells and supporting cells by mediating lateral inhibition via the ligands Delta-like 1 and Jagged (JAG 2. However, another Notch ligand, JAG1, is expressed early in the sensory patches prior to cell differentiation, indicating that there may be an earlier role for Notch signaling in sensory development in the ear. Here, using conditional gene targeting, we show that the Jag1 gene is required for the normal development of all six sensory organs within the inner ear. Cristae are completely lacking in Jag1-conditional knockout (cko mutant inner ears, whereas the cochlea and utricle show partial sensory development. The saccular macula is present but malformed. Using SOX2 and p27kip1 as molecular markers of the prosensory domain, we show that JAG1 is initially expressed in all the prosensory regions of the ear, but becomes down-regulated in the nascent organ of Corti by embryonic day 14.5, when the cells exit the cell cycle and differentiate. We also show that both SOX2 and p27kip1 are down-regulated in Jag1-cko inner ears. Taken together, these data demonstrate that JAG1 is expressed early in the prosensory domains of both the cochlear and vestibular regions, and is required to maintain the normal expression levels of both SOX2 and p27kip1. These data demonstrate that JAG1-mediated Notch signaling is essential during early development for establishing the prosensory regions of the inner ear.

  17. Effect of cochlear implant technology in sequentially bilaterally implanted adults.

    Science.gov (United States)

    Budenz, Cameron L; Roland, J Thomas; Babb, James; Baxter, Peter; Waltzman, Susan B

    2009-09-01

    Bilateral sequential cochlear implantation outcomes are dependent on many different factors. Newer technology in the second implanted ear may also contribute to outcome. This study examines the effect of cochlear implant technology on speech recognition outcomes in a population of adult patients who have undergone bilateral sequential implantation using different technologies in each ear. Retrospective chart review. Tertiary referral center. Twenty adults who underwent bilateral sequential cochlear implantation with different technologies and processing strategies in each ear were patients for this study. Control Group A included patients (n = 8) who were simultaneously implanted, and Control Group B (n = 3) were patients who were sequentially implanted with the same technology. Bilateral sequential cochlear implantation. The outcome measure was the Consonant-Nucleus-Consonant monosyllabic word test administered in each implanted ear and in the binaural condition before and 1 year after operation. A multivariate analysis was performed to account for factors including duration of deafness, length of device usage, and severity of deafness. There was significant improvement from before to 1 year after the operation in word scores for the individual ears and in the binaural condition for all groups. All patients were consistent users of both devices, and the use of different technology in the second implanted ear did not affect the patients' ability to benefit from bilateral implantation despite the use of different devices and processing strategies. Bilateral sequential implantation with newer and/or differing technology in the second implanted ear did not reduce the benefits of bilateral stimulation and should not be considered a deterrent to second-sided implantation.

  18. Biomaterials in cochlear implants

    Science.gov (United States)

    Stöver, Timo; Lenarz, Thomas

    2011-01-01

    The cochlear implant (CI) represents, for almost 25 years now, the gold standard in the treatment of children born deaf and for postlingually deafened adults. These devices thus constitute the greatest success story in the field of ‘neurobionic’ prostheses. Their (now routine) fitting in adults, and especially in young children and even babies, places exacting demands on these implants, particularly with regard to the biocompatibility of a CI’s surface components. Furthermore, certain parts of the implant face considerable mechanical challenges, such as the need for the electrode array to be flexible and resistant to breakage, and for the implant casing to be able to withstand external forces. As these implants are in the immediate vicinity of the middle-ear mucosa and of the junction to the perilymph of the cochlea, the risk exists – at least in principle – that bacteria may spread along the electrode array into the cochlea. The wide-ranging requirements made of the CI in terms of biocompatibility and the electrode mechanism mean that there is still further scope – despite the fact that CIs are already technically highly sophisticated – for ongoing improvements to the properties of these implants and their constituent materials, thus enhancing the effectiveness of these devices. This paper will therefore discuss fundamental material aspects of CIs as well as the potential for their future development. PMID:22073103

  19. Probing cochlear tuning and tonotopy in the tiger using otoacoustic emissions.

    Science.gov (United States)

    Bergevin, Christopher; Walsh, Edward J; McGee, JoAnn; Shera, Christopher A

    2012-08-01

    Otoacoustic emissions (sound emitted from the ear) allow cochlear function to be probed noninvasively. The emissions evoked by pure tones, known as stimulus-frequency emissions (SFOAEs), have been shown to provide reliable estimates of peripheral frequency tuning in a variety of mammalian and non-mammalian species. Here, we apply the same methodology to explore peripheral auditory function in the largest member of the cat family, the tiger (Panthera tigris). We measured SFOAEs in 9 unique ears of 5 anesthetized tigers. The tigers, housed at the Henry Doorly Zoo (Omaha, NE), were of both sexes and ranged in age from 3 to 10 years. SFOAE phase-gradient delays are significantly longer in tigers--by approximately a factor of two above 2 kHz and even more at lower frequencies--than in domestic cats (Felis catus), a species commonly used in auditory studies. Based on correlations between tuning and delay established in other species, our results imply that cochlear tuning in the tiger is significantly sharper than in domestic cat and appears comparable to that of humans. Furthermore, the SFOAE data indicate that tigers have a larger tonotopic mapping constant (mm/octave) than domestic cats. A larger mapping constant in tiger is consistent both with auditory brainstem response thresholds (that suggest a lower upper frequency limit of hearing for the tiger than domestic cat) and with measurements of basilar-membrane length (about 1.5 times longer in the tiger than domestic cat).

  20. Ear, Hearing and Speech

    DEFF Research Database (Denmark)

    Poulsen, Torben

    2000-01-01

    An introduction is given to the the anatomy and the function of the ear, basic psychoacoustic matters (hearing threshold, loudness, masking), the speech signal and speech intelligibility. The lecture note is written for the course: Fundamentals of Acoustics and Noise Control (51001)...

  1. Cochlear implantation in Pendred syndrome and non-syndromic enlarged vestibular aqueduct – clinical challenges, surgical results, and complications

    DEFF Research Database (Denmark)

    Mey, Kristianna; Bille, Michael; Cayé-Thomasen, Per

    2016-01-01

    or on populations with mixed cochlear malformations. PS/NSEVA accounts for up to 10% of congenital SNHL, rendering this a large group of cochlear implant candidates. The abnormal inner ear anatomy of these patients may be associated with a lower surgical success rate and a higher rate of complications. STUDY DESIGN...

  2. Localization ability with bimodal hearing aids and bilateral cochlear implants

    Science.gov (United States)

    Seeber, Bernhard U.; Baumann, Uwe; Fastl, Hugo

    2004-09-01

    After successful cochlear implantation in one ear, some patients continue to use a hearing aid at the contralateral ear. They report an improved reception of speech, especially in noise, as well as a better perception of music when the hearing aid and cochlear implant are used in this bimodal combination. Some individuals in this bimodal patient group also report the impression of an improved localization ability. Similar experiences are reported by the group of bilateral cochlear implantees. In this study, a survey of 11 bimodally and 4 bilaterally equipped cochlear implant users was carried out to assess localization ability. Individuals in the bimodal implant group were all provided with the same type of hearing aid in the opposite ear, and subjects in the bilateral implant group used cochlear implants of the same manufacturer on each ear. Subjects adjusted the spot of a computer-controlled laser-pointer to the perceived direction of sound incidence in the frontal horizontal plane by rotating a trackball. Two subjects of the bimodal group who had substantial residual hearing showed localization ability in the bimodal configuration, whereas using each single device only the subject with better residual hearing was able to discriminate the side of sound origin. Five other subjects with more pronounced hearing loss displayed an ability for side discrimination through the use of bimodal aids, while four of them were already able to discriminate the side with a single device. Of the bilateral cochlear implant group one subject showed localization accuracy close to that of normal hearing subjects. This subject was also able to discriminate the side of sound origin using the first implanted device alone. The other three bilaterally equipped subjects showed limited localization ability using both devices. Among them one subject demonstrated a side-discrimination ability using only the first implanted device.

  3. Statistical shape model with random walks for inner ear segmentation

    DEFF Research Database (Denmark)

    Pujadas, Esmeralda Ruiz; Kjer, Hans Martin; Piella, Gemma

    2016-01-01

    Cochlear implants can restore hearing to completely or partially deaf patients. The intervention planning can be aided by providing a patient-specific model of the inner ear. Such a model has to be built from high resolution images with accurate segmentations. Thus, a precise segmentation is requ...

  4. Computed tomographic features of the bony canal of the cochlear nerve in pediatric patients with unilateral sensorineural hearing loss

    International Nuclear Information System (INIS)

    Kono, Tatsuo

    2008-01-01

    The aim of this study was to evaluate the diameters of the various bony canals of the inner ear in patients with sensorineural hearing loss (SNHL) and establish criteria for detecting hypoplasia of the bony canal of the cochlear nerve. Measurements obtained in 118 patients without inner ear malformations among 160 patients with unilateral SNHL were analyzed. The diameters of the internal auditory canal and the bony canals of the cochlear, vestibular, and facial nerves were measured on transverse or coronal computed tomographic images. Mean values (±standard deviation (SD)) were compared between the affected and unaffected ears, and statistical analysis was done. The diameter of the bony canal of the cochlear nerve was significantly smaller in affected ears than in unaffected ears (P<0.01). The affected ears could be divided into groups with (72 ears) and without (46 ears) bony canal stenosis. Most (60%) of the patients with unilateral SNHL showed a significant difference in the diameters of the bony canals of the cochlear nerve between the affected and unaffected sides; moreover, the mean value was significantly smaller in affected ears. The diameter of <1.7 mm on transverse images or <1.8 mm on coronal images suggests hypoplasia. (author)

  5. Inner ear dysfunction in caspase-3 deficient mice

    Directory of Open Access Journals (Sweden)

    Woo Minna

    2011-10-01

    Full Text Available Abstract Background Caspase-3 is one of the most downstream enzymes activated in the apoptotic pathway. In caspase-3 deficient mice, loss of cochlear hair cells and spiral ganglion cells coincide closely with hearing loss. In contrast with the auditory system, details of the vestibular phenotype have not been characterized. Here we report the vestibular phenotype and inner ear anatomy in the caspase-3 deficient (Casp3-/- mouse strain. Results Average ABR thresholds of Casp3-/- mice were significantly elevated (P Casp3+/- mice and Casp3+/+ mice at 3 months of age. In DPOAE testing, distortion product 2F1-F2 was significantly decreased (P Casp3-/- mice, whereas Casp3+/- and Casp3+/+ mice showed normal and comparable values to each other. Casp3-/- mice were hyperactive and exhibited circling behavior when excited. In lateral canal VOR testing, Casp3-/- mice had minimal response to any of the stimuli tested, whereas Casp3+/- mice had an intermediate response compared to Casp3+/+ mice. Inner ear anatomical and histological analysis revealed gross hypomorphism of the vestibular organs, in which the main site was the anterior semicircular canal. Hair cell numbers in the anterior- and lateral crista, and utricle were significantly smaller in Casp3-/- mice whereas the Casp3+/- and Casp3+/+ mice had normal hair cell numbers. Conclusions These results indicate that caspase-3 is essential for correct functioning of the cochlea as well as normal development and function of the vestibule.

  6. Utility of bilateral acoustic hearing in combination with electrical stimulation provided by the cochlear implant.

    Science.gov (United States)

    Plant, Kerrie; Babic, Leanne

    2016-01-01

    The aim of the study was to quantify the benefit provided by having access to amplified acoustic hearing in the implanted ear for use in combination with contralateral acoustic hearing and the electrical stimulation provided by the cochlear implant. Measures of spatial and non-spatial hearing abilities were obtained to compare performance obtained with different configurations of acoustic hearing in combination with electrical stimulation. In the combined listening condition participants had access to bilateral acoustic hearing whereas the bimodal condition used acoustic hearing contralateral to the implanted ear only. Experience was provided with each of the listening conditions using a repeated-measures A-B-B-A experimental design. Sixteen post-linguistically hearing-impaired adults participated in the study. Group mean benefit was obtained with use of the combined mode on measures of speech recognition in coincident speech in noise, localization ability, subjective ratings of real-world benefit, and musical sound quality ratings. Access to bilateral acoustic hearing after cochlear implantation provides significant benefit on a range of functional measures.

  7. Successful outcomes of cochlear implantation in long-term unilateral deafness: brain plasticity?

    Science.gov (United States)

    Távora-Vieira, Dayse; Boisvert, Isabelle; McMahon, Catherine M; Maric, Vesna; Rajan, Gunesh P

    2013-09-11

    To investigate the implications of duration of deafness in the rehabilitation of unilateral deafness utilizing cochlear implantation. From the ongoing prospective cochlear implantation in unilateral deafness study, we looked at five adults who received a cochlear implant for long-term unilateral deafness. Speech perception in noise and subjective evaluation of the benefits of cochlear implantation were measured at 3, 6, and 12 months after implantation. The results were analyzed and compared with published data from normal hearing individuals and adults using cochlear implants bilaterally. Analysis of speech perception in noise showed significant improvement for three spatial configurations: speech and noise from the front (S0/N0; P=0.003), speech from the front and noise from the normal hearing ear (S0/NHE; P=0.001), speech from the implanted ear, and noise from the normal hearing ear (SCI/NHE; Pdeafness obtained scores in speech perception testing and in subjective evaluation that are similar to those attained by individuals with normal hearing and/or those with bilateral cochlear implants. Therefore, patients with postlingual unilateral deafness should not be excluded as cochlear implant candidates on the basis of a long duration of deafness.

  8. The Modified Rambo Transcanal Approach for Cochlear Implantation in CHARGE Syndrome.

    Science.gov (United States)

    Wick, Cameron C; Moore, Amy M; Killeen, Daniel E; Isaacson, Brandon

    2017-10-01

    CHARGE syndrome is associated with a variety of temporal bone anomalies and deafness. The lack of surgical landmarks and facial nerve irregularities make cochlear implantation in this population a challenging endeavor. This study aims to describe a safe and efficacious transcanal approach for cochlear implantation that obviates the need to perform a mastoidectomy and facial recess. Three children with profound hearing loss secondary to CHARGE syndrome. Transcanal cochlear implantation with closure of the ear canal via a modified Rambo meatoplasty. Retrospective chart review of temporal bone anomalies associated with CHARGE syndrome, technical nuances of this transcanal approach, and cochlear implant outcomes. The mean patient age was 2.5 years (range 1.5-3.8 yr). Two were male and two were left ears. All patients had a hypoplastic mastoid, semicircular canal aplasia, and had some degree of cochlear dysplasia. A full cochlear implant insertion was achieved in all cases, even in the presence of grossly abnormal middle ear and facial nerve anatomy. There were no intraoperative or postoperative complications. The mean follow-up was 12.4 months (range, 3.9-25.2 mo). All three patients use their device daily. Their guardians report improved vocalization and environmental awareness. The modified Rambo transcanal approach provides a safe corridor for cochlear implantation in patients with CHARGE syndrome. This approach minimizes the anatomical variations associated with the syndrome and may reduce the risk of electrode extrusion. Implant outcomes in this patient population remain highly variable based on the patient's global cognitive capacity.

  9. Can they dig it? Functional morphology and semifossoriality among small-eared shrews, genus Cryptotis (Mammalia, Soricidae).

    Science.gov (United States)

    Woodman, Neal; Gaffney, Sarah A

    2014-07-01

    Small-eared shrews (Mammalia: Soricidae: Cryptotis), exhibit modifications of the forelimb skeleton that have been interpreted as adaptations for semifossoriality. Most species inhabit remote regions, however, and their locomotory and foraging behaviors remain mostly speculative. To better understand the morphological modifications in the absence of direct observations, we quantified variation in these species by measuring 151 individuals representing 18 species and populations of Cryptotis and two species of moles (Talpidae) for comparison. From our measurements, we calculated 22 indices, most of which have been used previously to characterize substrate use among rodents and other taxa. We analyzed the indices using 1) average percentile ranks, 2) principal components analysis, and 3) cluster analysis. From these analyses, we determined that three basic modes of substrate adaptation are present within Cryptotis: 1) a primarily terrestrial mode, with species that are capable of burrowing, but lack adaptations to increase digging efficiency, 2) a semifossorial mode, with species whose forelimbs bones show strong muscle attachment areas and increased mechanical advantage, and 3) an intermediate mode. In addition to identifying new morphological characters and contributing to our understanding of the functional morphology of soricids, these analyses provide additional insight into the ecology of the species of interest. © 2014 Wiley Periodicals, Inc.

  10. Electrophysiological and Histopathological Evaluation of Effects of Sodium-2 Mercaptoethanesulfonate Used for Middle Ear Surgery on Facial Nerve Functions.

    Science.gov (United States)

    Eğilmez, Oğuz Kadir; Kökten, Numan; Baran, Mustafa; Kalcıoğlu, M Tayyar; Doğan Ekici, Işın; Tekin, Muhammet

    2017-12-14

    Sodium-2-mercaptoethanesulfonate (MESNA) is widely used in medicine because of its antioxidant and mucolytic effects. In recent years, it has been used in otologic surgery. Because it cleaves disulfide bonds, it is used to easily dissect the epithelial matrix in cholesteatoma and atelectasis. In this study, we hypothesized that MESNA does not have any toxic effect on the facial nerve, and the effects of MESNA on the facial nerve were examined histologically and electrophysiologically. Twenty Wistar albino rats were used. Groups A and B were designated as the control and sham groups, respectively. The animals in groups C and D were administered 20% and 50% of MESNA solution, respectively, after the facial nerve was exposed in the parotid region. Electromyography (EMG) measurements were performed preoperatively and postoperatively at 4 weeks. The animals were subsequently euthanized; facial nerve samples were taken for histopathological examination. When EMG parameters were compared within and between each group, preoperative and postoperative results were not statistically significantly different. Histopathological examination showed that MESNA did not cause any inflammation, granulation tissue, or foreign body reaction. To the best of our knowledge, the effects of MESNA on facial nerve functions have not been investigated. In this study, the effects of MESNA after direct application to the facial nerve were examined electrophysiologically and histologically, and it was determined that MESNA did not cause any toxic effects. It was concluded that MESNA can, therefore, be safely used during middle ear surgery.

  11. Inner-ear sound pressures near the base of the cochlea in chinchilla: Further investigation

    Science.gov (United States)

    Ravicz, Michael E.; Rosowski, John J.

    2013-01-01

    The middle-ear pressure gain GMEP, the ratio of sound pressure in the cochlear vestibule PV to sound pressure at the tympanic membrane PTM, is a descriptor of middle-ear sound transfer and the cochlear input for a given stimulus in the ear canal. GMEP and the cochlear partition differential pressure near the cochlear base ΔPCP, which determines the stimulus for cochlear partition motion and has been linked to hearing ability, were computed from simultaneous measurements of PV, PTM, and the sound pressure in scala tympani near the round window PST in chinchilla. GMEP magnitude was approximately 30 dB between 0.1 and 10 kHz and decreased sharply above 20 kHz, which is not consistent with an ideal transformer or a lossless transmission line. The GMEP phase was consistent with a roughly 50-μs delay between PV and PTM. GMEP was little affected by the inner-ear modifications necessary to measure PST. GMEP is a good predictor of ΔPCP at low and moderate frequencies where PV ⪢ PST but overestimates ΔPCP above a few kilohertz where PV ≈ PST. The ratio of PST to PV provides insight into the distribution of sound pressure within the cochlear scalae. PMID:23556590

  12. Cochlear Implant Using Neural Prosthetics

    Science.gov (United States)

    Gupta, Shweta; Singh, Shashi kumar; Dubey, Pratik Kumar

    2012-10-01

    This research is based on neural prosthetic device. The oldest and most widely used of these electrical, and often computerized, devices is the cochlear implant, which has provided hearing to thousands of congenitally deaf people in this country. Recently, the use of the cochlear implant is expanding to the elderly, who frequently suffer major hearing loss. More cutting edge are artificial retinas, which are helping dozens of blind people see, and ìsmartî artificial arms and legs that amputees can maneuver by thoughts alone, and that feel more like real limbs.Research, which curiosity led to explore frog legs dancing during thunderstorms, a snail shapedorgan in the inner ear, and how various eye cells react to light, have fostered an understanding of how to ìtalkî to the nervous system. That understanding combined with the miniaturization of electronics and enhanced computer processing has enabled prosthetic devices that often can bridge the gap in nerve signaling that is caused by disease or injury.

  13. [Cochlear implant treatment in Germany].

    Science.gov (United States)

    Jacob, R; Stelzig, Y

    2013-01-01

    Restoration of impaired auditory function through cochlear implant is possible, with high reliably and great success. Nevertheless, there are regular disputes between patients and insurance companies due to high costs. In Germany, approx. 1.9 Mio. people are severely hearing impaired. It can be estimated that for adequate hearing rehabilitation about 30,000 cochlear implants/year are necessary. Currently, less than 10% of those affected are offered cochlear implant. A handicap is defined if there is deviation from normal hearing for more than 6 months. This sets a time frame for the supply with cochlear implant after sudden deafness. The professional code requires to advice all medical options to a person seeking help for hearing loss. This includes benefit-risk consideration. At this point, the economic aspect plays no role. The indication for medical treatment is only subject to the treating physician and should not be modified by non-physicians or organizations. It should be noted that a supply of hearing aids is qualitatively different to the help from a cochlear implant, which provides a restoration of lost function. In social law (SGB V and IX) doctors are requested to advise and recommend all measures which contribute to normal hearing (both sides). This indicates that doctors may be prosecuted for not offering help when medically possible, just because health insurance employees did not approve the cost balance. The current situation, with insufficient medical care for the hearing impaired, needs clarifying. To do this, patients, health insurance companies, the political institutions, legislation and professional societies need to accept their responsibilities.

  14. Retrolabyrinthine approach for cochlear nerve preservation in neurofibromatosis type 2 and simultaneous cochlear implantation

    Directory of Open Access Journals (Sweden)

    Bento, Ricardo Ferreira

    2014-01-01

    Full Text Available Introduction: Few cases of cochlear implantation (CI in neurofibromatosis type 2 (NF2 patients had been reported in the literature. The approaches described were translabyrinthine, retrosigmoid or middle cranial fossa. Objectives: To describe a case of a NF2- deafened-patient who underwent to vestibular schwannoma resection via RLA with cochlear nerve preservation and CI through the round window, at the same surgical time. Resumed Report: A 36-year-old woman with severe bilateral hearing loss due to NF2 was submitted to vestibular schwannoma resection and simultaneous CI. Functional assessment of cochlear nerve was performed by electrical promontory stimulation. Complete tumor removal was accomplishment via RLA with anatomic and functional cochlear and facial nerve preservation. Cochlear electrode array was partially inserted via round window. Sound field hearing threshold improvement was achieved. Mean tonal threshold was 46.2 dB HL. The patient could only detect environmental sounds and human voice but cannot discriminate vowels, words nor do sentences at 2 years of follow-up. Conclusion: Cochlear implantation is a feasible auditory restoration option in NF2 when cochlear anatomic and functional nerve preservation is achieved. The RLA is adequate for this purpose and features as an option for hearing preservation in NF2 patients.

  15. Relationship between multipulse integration and speech recognition with cochlear implants.

    Science.gov (United States)

    Zhou, Ning; Pfingst, Bryan E

    2014-09-01

    Comparisons of performance with cochlear implants and postmortem conditions in the cochlea in humans have shown mixed results. The limitations in those studies favor the use of within-subject designs and non-invasive measures to estimate cochlear conditions. One non-invasive correlate of cochlear health is multipulse integration, established in an animal model. The present study used this measure to relate neural health in human cochlear implant users to their speech recognition performance. The multipulse-integration slopes were derived based on psychophysical detection thresholds measured for two pulse rates (80 and 640 pulses per second). A within-subject design was used in eight subjects with bilateral implants where the direction and magnitude of ear differences in the multipulse-integration slopes were compared with those of the speech-recognition results. The speech measures included speech reception threshold for sentences and phoneme recognition in noise. The magnitude of ear difference in the integration slopes was significantly correlated with the magnitude of ear difference in speech reception thresholds, consonant recognition in noise, and transmission of place of articulation of consonants. These results suggest that multipulse integration predicts speech recognition in noise and perception of features that use dynamic spectral cues.

  16. Distribution and possible function of lysosomal enzymes in the inner ear under normal and pathophysiological conditions.

    Science.gov (United States)

    Schätzle, W

    1976-05-31

    The normal distribution of several lysosomal enzymes was studied in 20 guinea pigs. In the outer hair cells lysosomal enzymes are mainly localized at the apical cell pole, while in inner hair cells the distribution was uniform. Nonlysosomal enzymes like alcaline phosphatase are of predominantly basal localization. The concentration of some lysosomal enzymes like N-acetyl-beta-glucosaminidase was higher in outer than in inner hair cells while others like acid phosphatase, beta-glucuronidase and sulfatase showed a stronger reaction in the inner hair cells. After 10 days of sound overstimulation with 120 dB for 1 h a day, there was an increase of lysosomal enzyme content namely in the outer hair cells. There was no change of non-lysosomal enzymes. Under these conditions there might be a partial destruction of cellular organelles eliminated by lysosomal activity without loss of a total cell. In addition the distribution and possible function of lysosomal enzymes in other labyrinthine tissues was discussed.

  17. Cochlear implant; Sharecropping discoveries vs surgical

    International Nuclear Information System (INIS)

    Mantilla M, Maria T; Pachon L, Francisco; Garcia, Juan M; Penaranda, Augusto

    1997-01-01

    Computed tomography (CT) of the ear is an important tool to decide if a patient is a candidate for cochlear implant. CT is a keystone in planning the surgery. Our purpose was to find out the incidence of anormalities and aetiologies in 84 patients with neuro sensorial hearing loss, submitted to a cochlear implant; establishing a correlation between the pre-implant high resolution computed tomography (HRTC) scans and the surgical findings. The most common causes of hearing loss were idiopathic (37/84), rubella (16/84), congenital anomaly (8/84), ototoxic medication (7/84), meningitis (6/84) and trauma (6/84). Sixteen abnormalities or anatomical features relevant for surgery were found in the 84 HRCT. Most of these findings were detected in the cochlea (11/84) and the vestibular aqueduct (6/84); the former related to labyrinthitis ossificans and Mondini anomaly, and the latter secondary to a large vestibular aqueduct

  18. Meningitis after cochlear implantation in Mondini malformation.

    Science.gov (United States)

    Page, E L; Eby, T L

    1997-01-01

    Although the potential for CSF leakage and subsequent meningitis after cochlear implantation in the malformed cochlea has been recognized, this complication has not been previously reported. We report a case of CSF otorhinorrhea and meningitis after minor head trauma developing 2 years after cochlear implantation in a child with Mondini malformation. Leakage of CSF was identified from the cochleostomy around the electrode of the implant, and this leak was sealed with a temporalis fascia and muscle plug. Although this complication appears to be rare, care must be taken to seal the cochleostomy in children with inner ear malformations at the initial surgery, and any episode of meningitis after surgery must be thoroughly investigated to rule out CSF leakage from the labyrinth.

  19. Ear infection - chronic

    Science.gov (United States)

    Middle ear infection - chronic; Otitis media - chronic; Chronic otitis media; Chronic ear infection ... blocked, fluid can build up. When this happens, infection can occur. A chronic ear infection develops when ...

  20. Ear infection - acute

    Science.gov (United States)

    ... Family history of ear infections Not being breastfed Pacifier use Recent ear infection Recent illness of any ... lead to fewer ear infections. DO NOT use pacifiers. Breastfeed -- this makes a child much less prone ...

  1. Gfi1 and Gfi1b act equivalently in haematopoiesis, but have distinct, non-overlapping functions in inner ear development.

    Science.gov (United States)

    Fiolka, Katharina; Hertzano, Ronna; Vassen, Lothar; Zeng, Hui; Hermesh, Orit; Avraham, Karen B; Dührsen, Ulrich; Möröy, Tarik

    2006-03-01

    Gfi1 is a transcriptional repressor essential for haematopoiesis and inner ear development. It shares with its paralogue Gfi1b an amino-terminal SNAG repressor domain and six carboxy-terminal zinc-finger motifs, but differs from Gfi1b in sequences separating these domains. Here, we describe two knock-in mouse models, in which the N-terminal SNAG repressor domain was mutated or in which the Gfi1 coding region was replaced by Gfi1b. Mouse mutants without an intact SNAG domain show the full phenotype of Gfi1 null mice. However, Gfi1:Gfi1b knock-in mice show almost normal pre-T-cell and neutrophil development, but lack properly formed inner ear hair cells. Hence, our findings show that an intact SNAG domain is essential for all functions of Gfi1 and that Gfi1b can replace Gfi1 functionally in haematopoiesis but, surprisingly, not in inner ear hair cell development, demonstrating that Gfi1 and Gfi1b have equivalent and domain-dependent, cell type-specific functions.

  2. Speech recognition outcomes following bilateral cochlear implantation in adults aged over 50 years old.

    Science.gov (United States)

    Boisvert, Isabelle; McMahon, Catherine M; Dowell, Richard C

    2016-01-01

    To examine the speech recognition benefit of bilateral cochlear implantation over unilateral implantation in adults aged over 50 years old, and to identify potential predictors of successful bilateral implantation in this group. Retrospective cohort study using data collected during standard clinical practice. Bilateral performance was compared to the unilateral performance with the first and second implanted ear and examined in relation to potential predictive variables. Sixty-seven cochlear implant users who received a second implant after the age of 50 years old. Participants obtained significantly greater speech recognition scores with the use of bilateral cochlear implants compared to the use of each individual implant. The score obtained with the first implanted ear was the most reliable predictor of the score obtained with the second and with bilateral implants. Older adults can obtain speech recognition benefits from sequential bilateral cochlear implantation.

  3. Phylogenetic and functional implications of the ear region anatomy of Glossotherium robustum (Xenarthra, Mylodontidae) from the Late Pleistocene of Argentina

    Science.gov (United States)

    Boscaini, Alberto; Iurino, Dawid A.; Billet, Guillaume; Hautier, Lionel; Sardella, Raffaele; Tirao, German; Gaudin, Timothy J.; Pujos, François

    2018-04-01

    Several detailed studies of the external morphology of the ear region in extinct sloths have been published in the past few decades, and this anatomical region has proved extremely helpful in elucidating the phylogenetic relationships among the members of this mammalian clade. Few studies of the inner ear anatomy in these peculiar animals were conducted historically, but these are increasing in number in recent years, in both the extinct and extant representatives, due to wider access to CT-scanning facilities, which allow non-destructive access to internal morphologies. In the present study, we analyze the extinct ground sloth Glossotherium robustum and provide a description of the external features of the ear region and the endocranial side of the petrosal bone, coupled with the first data on the anatomy of the bony labyrinth. Some features observable in the ear region of G. robustum (e.g., the shape and size of the entotympanic bone and the morphology of the posteromedial surface of the petrosal) are highly variable, both intraspecifically and intraindividually. The form of the bony labyrinth of G. robustum is also described, providing the first data from this anatomical region for the family Mylodontidae. The anatomy of the bony labyrinth of the genus Glossotherium is here compared at the level of the superorder Xenarthra, including all available extant and extinct representatives, using geometric morphometric methods. In light of the new data, we discuss the evolution of inner ear anatomy in the xenarthran clade, and most particularly in sloths, considering the influence of phylogeny, allometry, and physiology on the shape of this highly informative region of the skull. These analyses show that the inner ear of Glossotherium more closely resembles that of the extant anteaters, and to a lesser extent those of the giant ground sloth Megatherium and euphractine armadillos, than those of the extant sloths Bradypus and Choloepus, further demonstrating the striking

  4. Cochlear implantation feasibility in rhesus macaque monkey: anatomic and radiologic results.

    Science.gov (United States)

    Marx, Mathieu; Girard, Pascal; Escudé, Bernard; Barone, Pascal; Fraysse, Bernard; Deguine, Olivier

    2013-09-01

    Large animal models of implantable hearing devices are needed to assess innovative technologies before using them in humans. The rhesus macaque has cognitive abilities close to humans and has been used in the past but with noncommercial implants or no detailed radiologic descriptions of the surgical procedures. The aim of this study was to evaluate the feasibility of cochlear implantation in this animal model. We present detailed radiologic data (CT scan and Cone beam computed tomography) from 7 heads of rhesus macaque monkeys coming from autopsy materials. Several comparative measurements were performed with 10 human temporal bones to emphasize similarities and differences between the macaque and the human inner ear. The radiologic analyses helped planning the surgical approach for cochlear implant insertion in the macaque. We managed to perform one full (720 degrees) and 3 partial insertions (190-330 degrees) of cochlear implants in 4 rhesus macaque cochleae, documented by cone beam computed tomography reconstructions. We confirm that the procedure is facilitated in this animal because the cochlea dimensions are close to humans. However, marked differences in the orientation of the external auditory canal and the basal turn must be taken into account. We suggest that the removal of the inferior wall of tympanal bone provides the optimal axis for electrode array insertion. The rhesus macaque monkey is a valid and close-to-human animal model for cochlear implants insertion. Because this species is widely used in both behavioral and physiologic studies, we expect that functional implants can be coupled with electrophysiologic recordings to study the mechanisms of auditory compensation.

  5. Ototoxicidade e otoproteção em orelha interna de cobaias utilizando gentamicina e amicacina: aspectos ultra-estruturais e funcionais Ototoxicity and otoprotection in the inner ear of guinea pigs using gentamicin and amikacin: ultrastructural and functional aspects

    Directory of Open Access Journals (Sweden)

    Thomaz José Marra de Aquino

    2008-12-01

    Full Text Available A ototoxicidade ainda é um desafio para medicina. A descoberta dos mecanismos endógenos autoprotetores das células ciliadas externas associados a métodos de avaliação funcional e ultra-estrutural das mesmas abriu nova perspectiva no entendimento e controle destes mecanismos. OBJETIVO: O trabalho objetivou determinar se subdoses de gentamicina protegia contra ototoxicidade da amicacina baseado nestes mecanismos e determinar se a amplitude das emissões otoacústicas teria correlação com grau de integridade das células ciliadas. MATERIAL E MÉTODO: Estudo experimental. Utilizando 31 cobaias, administrou-se soro fisiológico, gentamicina e amicacina, isoladamente e associadas, via intramuscular, por 12, 30 e 42 dias. Pesquisa de emissões otoacústicas foi realizada no início e final do experimento, comparado com estudo da integridade coclear, por microscopia eletrônica. RESULTADOS: Subdoses de gentamicina não protegeram a orelha interna contra toxicidade da amicacina; diminuições da amplitude das emissões otoacústicas apresentaram forte correlação com aumento de lesões das células ciliadas. CONCLUSÃO: Os achados contribuem para o entendimento dos mecanismos de ototoxicidade e otoproteção da orelha interna. A determinação da correlação entre amplitude de emissões e integridade celular tem grande importância no acompanhamento das lesões de células ciliadas, com possível aplicação no monitoramento de ototoxicidade por drogas em humanos.Ototoxicity is still a challenge to medicine. The discovery of self-protecting endogenous mechanisms of the outer hair cells associated with their functional and ultra-structural assessment methods has opened new horizons in the understanding and controlling of these mechanisms. AIM: this paper aimed at establishing whether or not underdoses of gentamicin could protect the inner ear against the harmful effects of amikacin, based on these protection mechanisms and determine if the

  6. Ear-to-Ear On-Body Channel Fading in the ISM-band for Tangentially-Polarized Antennas

    DEFF Research Database (Denmark)

    Kvist, Søren Helstrup; Thaysen, Jesper; Jakobsen, Kaj Bjarne

    2011-01-01

    The ear-to-ear on-body channel fading has been studied in the ISM-band. The ear-to-ear path gain was measured on six persons in an indoor environment for a duration of 200 s. The channel fading has been characterized in terms of empirical cumulative distribution functions (CDF), average fade...

  7. [European Portuguese EARS test battery adaptation].

    Science.gov (United States)

    Alves, Marisa; Ramos, Daniela; Oliveira, Graça; Alves, Helena; Anderson, Ilona; Magalhães, Isabel; Martins, Jorge H; Simões, Margarida; Ferreira, Raquel; Fonseca, Rita; Andrade, Susana; Silva, Luís; Ribeiro, Carlos; Ferreira, Pedro Lopes

    2014-01-01

    The use of adequate assessment tools in health care is crucial for the management of care. The lack of specific tools in Portugal for assessing the performance of children who use cochlear implants motivated the translation and adaptation of the EARS (Evaluation of Auditory Responses to Speech) test battery into European Portuguese. This test battery is today one of the most commonly used by (re)habilitation teams of deaf children who use cochlear implants worldwide. The goal to be achieved with the validation of EARS was to provide (re)habilitation teams an instrument that enables: (i) monitoring the progress of individual (re)habilitation, (ii) managing a (re)habilitation program according to objective results, comparable between different (re)habilitation teams, (iii) obtaining data that can be compared with the results of international teams, and (iv) improving engagement and motivation of the family and other professionals from local teams. For the test battery translation and adaptation process, the adopted procedures were the following: (i) translation of the English version into European Portuguese by a professional translator, (ii) revision of the translation performed by an expert panel, including doctors, speech-language pathologists and audiologists, (iii) adaptation of the test stimuli by the team's speechlanguage pathologist, and (iv) further review by the expert panel. For each of the tests that belong to the EARS battery, the introduced adaptations and adjustments are presented, combining the characteristics and objectives of the original tests with the linguistic and cultural specificities of the Portuguese population. The difficulties that have been encountered during the translation and adaptation process and the adopted solutions are discussed. Comparisons are made with other versions of the EARS battery. We defend that the translation and the adaptation process followed for the EARS test battery into European Portuguese was correctly conducted

  8. Image Registration of Cochlear µCT Data Using Heat Distribution Similarity

    DEFF Research Database (Denmark)

    Kjer, Hans Martin; Vera, Sergio; Fagertun, Jens

    2015-01-01

    Better understanding of the anatomical variability of the human cochlear is important for the design and function of Cochlear Implants. Good non-rigid alignment of high-resolution cochlear μCT data is a challenging task. In this paper we study the use of heat distribution similarity between sampl...

  9. Communication outcomes following cochlear implantation in a child with cystic cochleovestibular anomaly

    OpenAIRE

    Banumathy, N.; Panda, Naresh

    2016-01-01

    Cochlear implantation is one of the best amongst the various management options available for children and adults with severe to profound sensorineural hearing loss. Inner ear and internal auditory canal (IAC) malformations accounts to approximately 25% of congenital sensorineural hearing loss in children. The primary goal of this report was to evaluate the communication outcomes after cochlear implantation in a child with cystic cochleovestibular anomaly (CCVA). The child was evaluated throu...

  10. [Cochlear implantation in patients with Waardenburg syndrome type II].

    Science.gov (United States)

    Wan, Liangcai; Guo, Menghe; Chen, Shuaijun; Liu, Shuangriu; Chen, Hao; Gong, Jian

    2010-05-01

    To describe the multi-channel cochlear implantation in patients with Waardenburg syndrome including surgeries, pre and postoperative hearing assessments as well as outcomes of speech recognition. Multi-channel cochlear implantation surgeries have been performed in 12 cases with Waardenburg syndrome type II in our department from 2000 to 2008. All the patients received multi-channel cochlear implantation through transmastoid facial recess approach. The postoperative outcomes of 12 cases were compared with 12 cases with no inner ear malformation as a control group. The electrodes were totally inserted into the cochlear successfully, there was no facial paralysis and cerebrospinal fluid leakage occurred after operation. The hearing threshold in this series were similar to that of the normal cochlear implantation. After more than half a year of speech rehabilitation, the abilities of speech discrimination and spoken language of all the patients were improved compared with that of preoperation. Multi-channel cochlear implantation could be performed in the cases with Waardenburg syndrome, preoperative hearing and images assessments should be done.

  11. Investigating Science Student Teachers' Ideas about Function and Anatomical Form of Two Human Sensory Organs, the Eye and the Ear

    Science.gov (United States)

    Kunt, Halil

    2016-01-01

    The purpose of this research was to determine science student teachers' level of knowledge about the anatomical structure of two sensory organs, the eye and the ear, in addition to vision and hearing processes. Conducted with 86 science student teachers, research utilized drawing methods and open-ended questions as data collection instruments. The…

  12. Functional Ear (A)Symmetry in Brainstem Neural Activity Relevant to Encoding of Voice Pitch: A Precursor for Hemispheric Specialization?

    Science.gov (United States)

    Krishnan, Ananthanarayan; Gandour, Jackson T.; Ananthakrishnan, Saradha; Bidelman, Gavin M.; Smalt, Christopher J.

    2011-01-01

    Pitch processing is lateralized to the right hemisphere; linguistic pitch is further mediated by left cortical areas. This experiment investigates whether ear asymmetries vary in brainstem representation of pitch depending on linguistic status. Brainstem frequency-following responses (FFRs) were elicited by monaural stimulation of the left and…

  13. Measurement of acoustic impedance and reflectance in the human ear canal.

    Science.gov (United States)

    Voss, S E; Allen, J B

    1994-01-01

    The pressure reflectance R (omega) is the transfer function which may be defined for a linear one-port network by the ratio of the reflected complex pressure divided by the incident complex pressure. The reflectance is a function that is closely related to the impedance of the 1-port. The energy reflectance R (omega) is defined as magnitude of [R]2. It represents the ratio of reflected to incident energy. In the human ear canal the energy reflectance is important because it is a measure of the inefficiency of the middle ear and cochlea, and because of the insight provided by its simple frequency domain interpretation. One may characterize the ear canal impedance by use of the pressure reflectance and its magnitude, sidestepping the difficult problems of (a) the unknown canal length from the measurement point to the eardrum, (b) the complicated geometry of the drum, and (c) the cross-sectional area changes in the canal as a function of distance. Reported here are acoustic impedance measurements, looking into the ear canal, measured on ten young adults with normal hearing (ages 18-24). The measurement point in the canal was approximately 0.85 cm from the entrance of the canal. From these measurements, the pressure reflectance in the canal is computed and impedance and reflectance measurements from 0.1 to 15.0 kHz are compared among ears. The average reflectance and the standard deviation of the reflectance for the ten subjects have been determined. The impedance and reflectance of two common ear simulators, the Brüel & Kjaer 4157 and the Industrial Research Products DB-100 (Zwislocki) coupler are also measured and compared to the average human measurements. All measurements are made using controls that assure a uniform accuracy in the acoustic calibration across subjects. This is done by the use of two standard acoustic resistors whose impedances are known. From the experimental results, it is concluded that there is significant subject variability in the magnitude

  14. Play it by Ear

    DEFF Research Database (Denmark)

    Kammersgaard, Nikolaj Peter Iversen; Kvist, Søren Helstrup; Thaysen, Jesper

    2014-01-01

    The first antenna for ear-to-ear communication with a standard Bluetooth chip has the potential to improve hearing aid technology.......The first antenna for ear-to-ear communication with a standard Bluetooth chip has the potential to improve hearing aid technology....

  15. A Case of Cochlear Implantation in Bromate-Induced Bilateral Sudden Deafness.

    Science.gov (United States)

    Eom, Tae-Ho; Lee, Sungsu; Cho, Hyong-Ho; Cho, Yong-Beom

    2015-04-01

    Despite the well-established nature of bromate-induced ototoxicity, cochlear implantation after bromate intoxication has been rarely documented. We hereby present a case of a 51-year-old female deafened completely after bromate ingestion. Her hearing was not restored by systemic steroid treatment and hearing aids were of no use. A cochlear implantation was performed on her right ear 3 months after the bromate ingestion. In bromate intoxication cases, early monitoring of hearing level is necessary and other drugs with potential ototoxicity should be avoided. The outcome of cochlear implantation was excellent in this case of bromate-induced deafness.

  16. Simultaneous Bilateral Cochlear Implantation for a 6-Month Child with a History of Meningitis

    Directory of Open Access Journals (Sweden)

    Kh. M. Diab

    2015-01-01

    Full Text Available The article presents the first case of simultaneous bilateral cochlear implantation for a 6-month child with IV degree sensorineural hearing loss after meningocephalitis in Russia. Despite partial ossification of the cochlear basal turns, the early timing of implantation allowed to fully implant active electrodes to both ears. The simultaneous bilateral cochlear implantation in young children, who had meningitis, is a minimally invasive and highly efficient procedure with good long-term results of oral-aural after-care.

  17. Hearing Preservation Outcomes for 139 Cochlear Implant Recipients Using a Thin Straight Electrode Array.

    Science.gov (United States)

    Moran, Michelle; Dowell, Richard C; Iseli, Claire; Briggs, Robert J S

    2017-06-01

    To assess the hearing preservation outcomes in a large group of adult cochlear implant recipients implanted with a thin straight electrode array using atraumatic surgical techniques. Factors affecting hearing preservation will be investigated. Prospective cohort study undertaken at the Royal Victorian Eye and Ear Hospital in Melbourne, Australia from December 2010 to May 2015. Tertiary academic hospital. One hundred thirty-nine adults undergoing cochlear implantation (CI). Primary outcome measure of interest was pre and postoperative pure-tone audiometry. Median low-frequency hearing change for the whole group of 139 recipients was -22.5 dB at the 3 months postop point. Eighty-six participants had functional preoperative low-frequency hearing (≤70 dB average at 250 and 500 Hz). Of these, 90.7% retained measureable hearing at 3 months postimplant. 39.5% of this original 86 participants retained functional hearing at 3 months postimplant. At 12 months postimplant, those who retained functional hearing at 3 months had no significant change in hearing. The group who lost functional hearing continued to have a significant deterioration in low-frequency hearing. Degree of hearing loss preimplant was identified as a predictor for the preservation of hearing postoperatively. Preservation of hearing is possible following atraumatic cochlear implant surgery with a thin straight electrode array. The amount of hearing preserved seems to be variable, and factors related to this variability are not yet known. The results of the present study suggest preoperative low-frequency hearing at or better than 45 dB may be related to preservation of functional hearing.

  18. Autoimmune Inner Ear Disease- A Clinical Viewpoint

    Directory of Open Access Journals (Sweden)

    Amirala Khalessi

    2010-10-01

    Full Text Available Recent developments in medicine have given us a better insight into a group of disorders known as autoimmune diseases. In particular, advances have occurred in our understanding of the Autoimmune Inner Ear Disease (AIED. In this article, the authors review the different postulated theories in the pathogenesis of this disease. The clinical presentation, the available para-clinical diagnostic tools, and the important differential diagnoses will be summarized. The management methods, including steroid therapy, immunosuppressive medications, other biological agents and intra-tympanic injections, will be addressed. Cochlear implantation as a final solution to the advanced stages of the disease, causing total deafness, will also be discussed.

  19. Development and function of the voltage-gated sodium current in immature mammalian cochlear inner hair cells.

    Directory of Open Access Journals (Sweden)

    Tobias Eckrich

    Full Text Available Inner hair cells (IHCs, the primary sensory receptors of the mammalian cochlea, fire spontaneous Ca(2+ action potentials before the onset of hearing. Although this firing activity is mainly sustained by a depolarizing L-type (Ca(V1.3 Ca(2+ current (I(Ca, IHCs also transiently express a large Na(+ current (I(Na. We aimed to investigate the specific contribution of I(Na to the action potentials, the nature of the channels carrying the current and whether the biophysical properties of I(Na differ between low- and high-frequency IHCs. We show that I(Na is highly temperature-dependent and activates at around -60 mV, close to the action potential threshold. Its size was larger in apical than in basal IHCs and between 5% and 20% should be available at around the resting membrane potential (-55 mV/-60 mV. However, in vivo the availability of I(Na could potentially increase to >60% during inhibitory postsynaptic potential activity, which transiently hyperpolarize IHCs down to as far as -70 mV. When IHCs were held at -60 mV and I(Na elicited using a simulated action potential as a voltage command, we found that I(Na contributed to the subthreshold depolarization and upstroke of an action potential. We also found that I(Na is likely to be carried by the TTX-sensitive channel subunits Na(V1.1 and Na(V1.6 in both apical and basal IHCs. The results provide insight into how the biophysical properties of I(Na in mammalian cochlear IHCs could contribute to the spontaneous physiological activity during cochlear maturation in vivo.

  20. Threshold shift: effects of cochlear implantation on the risk of pneumococcal meningitis.

    Science.gov (United States)

    Wei, Benjamin P C; Shepherd, Robert K; Robins-Browne, Roy M; Clark, Graeme M; O'Leary, Stephen J

    2007-04-01

    The study goals were to examine whether cochlear implantation increases the risk of meningitis in the absence of other risk factors and to understand the pathogenesis of pneumococcal meningitis post cochlear implantation. Four weeks following surgery, 54 rats (18 of which received a cochleostomy alone, 18 of which received a cochleostomy and acute cochlear implantation using standard surgical techniques, and 18 of which received a cochlear implant) were infected with Streptococcus pneumoniae via three different routes of bacterial inoculation (middle ear, inner ear, and intraperitoneal) to represent all potential routes of bacterial infection from the upper respiratory tract to the meninges. The presence of a cochlear implant reduced the threshold of bacteria required to cause pneumococcal meningitis from all routes of infection in healthy animals. The presence of a cochlear implant increases the risk of pneumococcal meningitis regardless of the route of bacterial infection. Early detection and treatment of pneumococcal infection such as otitis media may be required, as cochlear implantation may lead to a reduction of infectious threshold for meningitis.

  1. Bacterial Invasion of the Inner Ear in Association With Pneumococcal Meningitis

    DEFF Research Database (Denmark)

    Møller, Martin Nue; Brandt, Christian; Østergaard, Christian

    2014-01-01

    OBJECTIVE: To examine the pathways of bacterial invasion and subsequent spreading in the inner ear during pneumococcal meningitis. STUDY DESIGN: A well-established adult rat model of Streptococcus pneumoniae meningitis was used. METHODS: Thirty rats were inoculated intrathecally with S. pneumoniae...... spreading were found within the inner ear. Bacterial elimination was evidenced by engulfment by macrophages within the inner ear. CONCLUSION: From the meninges, pneumococci invade the inner ear through the cochlear aqueduct during the first days of infection, whereas hematogenous invasion via the spiral...

  2. Delivery of Adeno-Associated Virus Vectors in Adult Mammalian Inner-Ear Cell Subtypes Without Auditory Dysfunction.

    Science.gov (United States)

    Tao, Yong; Huang, Mingqian; Shu, Yilai; Ruprecht, Adam; Wang, Hongyang; Tang, Yong; Vandenberghe, Luk H; Wang, Qiuju; Gao, Guangping; Kong, Wei-Jia; Chen, Zheng-Yi

    2018-01-22

    Hearing loss, including genetic hearing loss, is one of the most common forms of sensory deficits in humans with limited options of treatment. Adeno-associated virus (AAV)-mediated gene transfer has been shown to recover auditory functions effectively in mouse models of genetic deafness when delivered at neonatal stages. However, the mouse cochlea is still developing at those time points, whereas in humans, the newborn inner ears are already fully mature. For effective gene therapy to treat genetic deafness, it is necessary to determine whether AAV-mediated therapy can be equally effective in the fully mature mouse inner ear without causing damage to the inner ear. This study tested several AAV serotypes by canalostomy in adult mice. It is shown that most AAVs transduce the sensory inner hair cells efficiently, but are less efficient at transducing outer hair cells. A subset of AAVs also transduces non-sensory cochlear cell types. Neither the surgical procedure of canalostomy nor the AAV serotypes damage hair cells or impair normal hearing. The studies indicate that canalostomy can be a viable route for safe and efficient gene delivery, and they expand the repertoire of AAVs to target diverse cell types in the adult inner ear.

  3. Congenital inner ear malformations without sensorineural hearing loss.

    Science.gov (United States)

    Yukawa, Kumiko; Horiguchi, Satoshi; Suzuki, Mamoru

    2008-03-01

    It has been reported that normal hearing is rare in patients with severe inner ear vestibular malformations [Kokai H, Oohashi M, Ishikawa K, Harada K, Hiratsuka H, Ogasawara M et al. Clinical review of inner ear malformation. J Otolaryngol Jpn 2003;106(10):1038-44; Schuknecht HF. Mondini dysplasia. A clinical pathological study. Ann Otol Rhinol Laryngol 1980;89(Suppl. 65):1-23; Jackler RK, Luxford WM, House WF. Congenital malformations of the inner ear: a classification based on embryogenesis. Laryngoscope 1987;97:2-14; Phelps PD. Congenital lesions of the inner ear, demonstrated by tomography. Arch Otolaryngol 1974;100:11-8]. A 37-year-old woman had combined dysplasia of the posterior and lateral semicircular canals (PSCC, LSCC) with normal cochlear development and normal hearing in both ears. She had complained of dizziness for 8 months. High resolution computed tomography (CT) showed hypogenesis of the bony labyrinth in both ears. Bilateral PSCC and LSCC dysplasia and dilatation of the vestibule were detected. Magnetic resonant imaging (MRI) revealed that the deformity of the PSCC was more severe than the LSCC. Although the caloric test of the left ear elicited no nystagmus and there was reduced response in the right ear, the horizontal vestibulo-occular reflex (VOR) was present. Her dizzy sensation disappeared within 3 months without special treatment. The dizziness attack might have been caused by a temporary breakdown of her peripheral vestibular system.

  4. Hearing Preservation in Cochlear Implant Surgery

    Directory of Open Access Journals (Sweden)

    Priscila Carvalho Miranda

    2014-01-01

    Full Text Available In the past, it was thought that hearing loss patients with residual low-frequency hearing would not be good candidates for cochlear implantation since insertion was expected to induce inner ear trauma. Recent advances in electrode design and surgical techniques have made the preservation of residual low-frequency hearing achievable and desirable. The importance of preserving residual low-frequency hearing cannot be underestimated in light of the added benefit of hearing in noisy atmospheres and in music quality. The concept of electrical and acoustic stimulation involves electrically stimulating the nonfunctional, high-frequency region of the cochlea with a cochlear implant and applying a hearing aid in the low-frequency range. The principle of preserving low-frequency hearing by a “soft surgery” cochlear implantation could also be useful to the population of children who might profit from regenerative hair cell therapy in the future. Main aspects of low-frequency hearing preservation surgery are discussed in this review: its brief history, electrode design, principles and advantages of electric-acoustic stimulation, surgical technique, and further implications of this new treatment possibility for hearing impaired patients.

  5. Molecular Mechanisms of Inner Ear Development

    OpenAIRE

    Wu, Doris K.; Kelley, Matthew W.

    2012-01-01

    The inner ear is a structurally complex vertebrate organ built to encode sound, motion, and orientation in space. Given its complexity, it is not surprising that inner ear dysfunction is a relatively common consequence of human genetic mutation. Studies in model organisms suggest that many genes currently known to be associated with human hearing impairment are active during embryogenesis. Hence, the study of inner ear development provides a rich context for understanding the functions of gen...

  6. Tyrosine Hydroxylase Expression in Type II Cochlear Afferents in Mice.

    Science.gov (United States)

    Vyas, Pankhuri; Wu, Jingjing Sherry; Zimmerman, Amanda; Fuchs, Paul; Glowatzki, Elisabeth

    2017-02-01

    Acoustic information propagates from the ear to the brain via spiral ganglion neurons that innervate hair cells in the cochlea. These afferents include unmyelinated type II fibers that constitute 5 % of the total, the majority being myelinated type I neurons. Lack of specific genetic markers of type II afferents in the cochlea has been a roadblock in studying their functional role. Unexpectedly, type II afferents were visualized by reporter proteins induced by tyrosine hydroxylase (TH)-driven Cre recombinase. The present study was designed to determine whether TH-driven Cre recombinase (TH-2A-CreER) provides a selective and reliable tool for identification and genetic manipulation of type II rather than type I cochlear afferents. The "TH-2A-CreER neurons" radiated from the spiral lamina, crossed the tunnel of Corti, turned towards the base of the cochlea, and traveled beneath the rows of outer hair cells. Neither the processes nor the somata of TH-2A-CreER neurons were labeled by antibodies that specifically labeled type I afferents and medial efferents. TH-2A-CreER-positive processes partially co-labeled with antibodies to peripherin, a known marker of type II afferents. Individual TH-2A-CreER neurons gave off short branches contacting 7-25 outer hair cells (OHCs). Only a fraction of TH-2A-CreER boutons were associated with CtBP2-immunopositive ribbons. These results show that TH-2A-CreER provides a selective marker for type II versus type I afferents and can be used to describe the morphology and arborization pattern of type II cochlear afferents in the mouse cochlea.

  7. Inner ear dysplasia is common in children with Down syndrome (trisomy 21).

    Science.gov (United States)

    Blaser, Susan; Propst, Evan J; Martin, Daniel; Feigenbaum, Annette; James, Adrian L; Shannon, Patrick; Papsin, Blake C

    2006-12-01

    Middle and external ear anomalies are well recognized in Down syndrome (DS, trisomy 21). Inner ear anomalies are much less frequently described. This study reviews inner ear morphology on imaging to determine the prevalence of cochlear and vestibular anomalies in children with DS. The authors conducted a retrospective review of imaging features of (DS) inner ear structures. Fifty-nine sequential patients with DS with imaging of the inner ear were identified by a radiology report text search program. Quantitative biometric assessment of the inner ear was performed on patients with high-resolution computed tomography or magnetic resonance images of the petrous bone. Petrous imaging was performed for evaluation of inflammatory disease or hearing loss. Spinal imaging, which included petrous views, was performed in most cases to exclude C1 to 2 dislocation, a potential complication of DS. Measurements were compared with normative data. Inner ear dysplasia is much more common in DS than previously reported. Inner ear structures are universally hypoplastic. Vestibular malformations are particularly common and a small bony island of the lateral semicircular canal (vestibule into a single cavity, vestibular aqueduct and endolymphatic sac fossa enlargement, cochlear nerve canal hypoplasia, and stenosis or duplication of the internal auditory canal. Stenosis of the external meatus, poor mastoid pneumatization, middle ear and mastoid opacification, and cholesteatoma were common, as expected.

  8. To Have an Ear: Music and the Otological Experience.

    Science.gov (United States)

    Sattar, Atia

    2016-09-01

    This essay analyzes the historical development of otology in relation to music. It illustrates the integral role of music perception and appreciation in the study of hearing, where hearing operates not simply as a scientific phenomenon but signifies particular meaningful experiences in society. The four historical moments considered-Helmholtz's piano-keyed cochlea, the ear phonautograph, the hearing aid, and the cochlear implant-show how the sounds, perceptions, and instruments of music have mediated and continue to mediate our relationships with hearing. To have an ear, one does not just bear a physiological hearing mechanism; one experiences the aesthetics of musical sound.

  9. [Clinical analysis of 102 patients with congenital inner ear malformation].

    Science.gov (United States)

    Zhu, X; Lian, N; Cai, Z

    1995-01-01

    Hearing loss and CT findings of 200 ears from 102 cases with congenital malformation of inner ear were included in our study. Hearing loss was typically bilateral severe, or total deafness. 75 percent of them were found deaf within one-year-old. In addition, 47 patients' (46%) mothers were noted to have caught a cold in first trimester of pregnancy. Temporal bone abnormalties were described as five types: 1. Michel malformation, 2. Mondini malformation, 3. enlargement of the vestibular aqueducts, 4. developmental deformity of cochlear aqueduct, 5. developmental deformity of internal acoustic meatus. Most cases showed malformations of vestibule or vestibular aqueducts.

  10. 3D printed bionic ears.

    Science.gov (United States)

    Mannoor, Manu S; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A; Soboyejo, Winston O; Verma, Naveen; Gracias, David H; McAlpine, Michael C

    2013-06-12

    The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing.

  11. Effect of ambient temperature and energy demands on digestive functions in leaf-eared mice (Phyllotis darwini) from central Chile

    Science.gov (United States)

    Bozinovic, F.; Nespolo, Roberto F.

    The leaf-eared mouse, Phyllotis darwini, is a nocturnal rodent inhabiting the semiarid and Mediterranean habitats of northern and central Chile. Previous observations suggested that in the field, individuals may change food intake according to seasonal changes in ambient temperature. We therefore anticipated that P. darwini should increase food intake in response to lower ambient temperature. As predicted, results of food trials and digestive measurements demonstrated that P. darwini increases food intake and assimilation at lower ambient temperatures but does not increase food mean retention time. At lower ambient temperatures, individuals increase digestive tract size thus improving body mass maintenance and perhaps survival during winter.

  12. Protective role of hydrogen sulfide against noise-induced cochlear damage: a chronic intracochlear infusion model.

    Directory of Open Access Journals (Sweden)

    Xu Li

    Full Text Available BACKGROUND: A reduction in cochlear blood flow plays an essential role in noise-induced hearing loss (NIHL. The timely regulation of cochlear perfusion determines the progression and prognosis of NIHL. Hydrogen sulfide (H(2S has attracted increasing interest as a vasodilator in cardiovascular systems. This study identified the role of H(2S in cochlear blood flow regulation and noise protection. METHODOLOGY/PRINCIPAL FINDINGS: The gene and protein expression of the H(2S synthetase cystathionine-γ-lyase (CSE in the rat cochlea was examined using immunofluorescence and real-time PCR. Cochlear CSE mRNA levels varied according to the duration of noise exposure. A chronic intracochlear infusion model was built and artificial perilymph (AP, NaHS or DL-propargylglycine (PPG were locally administered. Local sodium hydrosulfide (NaHS significantly increased cochlear perfusion post-noise exposure. Cochlear morphological damage and hearing loss were alleviated in the NaHS group as measured by conventional auditory brainstem response (ABR, cochlear scanning electron microscope (SEM and outer hair cell (OHC count. The highest percentage of OHC loss occurred in the PPG group. CONCLUSIONS/SIGNIFICANCE: Our results suggest that H(2S plays an important role in the regulation of cochlear blood flow and the protection against noise. Further studies may identify a new preventive and therapeutic perspective on NIHL and other blood supply-related inner ear diseases.

  13. A new computed tomography method to identify meningitis-related cochlear ossification and fibrosis before cochlear implantation.

    Science.gov (United States)

    Ichikawa, Kazunori; Kashio, Akinori; Mori, Harushi; Ochi, Atushi; Karino, Shotaro; Sakamoto, Takashi; Kakigi, Akinobu; Yamasoba, Tatsuya

    2014-04-01

    To develop a new method to determine the presence of intracochlear ossification and/or fibrosis in cochlear implantation candidates with bilateral profound deafness following meningitis. Diagnostic test assessment. A university hospital. This study involved 15 ears from 13 patients with profound deafness following meningitis who underwent cochlear implantation. These ears showed normal structures, soft tissue, partial bony occlusion, and complete bony occlusion in 4, 3, 2, and 6 ears, respectively. We measured radiodensity in Hounsfield units (HU) using 0.5-mm-thick axial high-resolution computed tomography image slices at 3 different levels in the basal turn, the fenestration, and inferior and ascending segment sites, located along the electrode-insertion path. Pixel-level analysis on the DICOM viewer yielded actual computed tomography values of intracochlear soft tissues by eliminating the partial volume effect. The values were compared with the intraoperative findings. Values for ossification (n = 12) ranged from +547 HU to +1137 HU; for fibrosis (n = 11), from +154 HU to +574 HU; and for fluid (n = 22), from -49 HU to +255 HU. From these values, we developed 2 presets of window width (WW) and window level (WL): (1) WW: 1800, WL: 1100 (200 HU to 2000 HU) and (2) WW: 1500, WL: 1250 (500 HU to 2000 HU). The results using these 2 presets corresponded well to the intraoperative findings. Our new method is easy and feasible for preoperative determination of the presence of cochlear ossification and/or fibrosis that develops following meningitis.

  14. Molecular mechanisms of inner ear development.

    Science.gov (United States)

    Wu, Doris K; Kelley, Matthew W

    2012-08-01

    The inner ear is a structurally complex vertebrate organ built to encode sound, motion, and orientation in space. Given its complexity, it is not surprising that inner ear dysfunction is a relatively common consequence of human genetic mutation. Studies in model organisms suggest that many genes currently known to be associated with human hearing impairment are active during embryogenesis. Hence, the study of inner ear development provides a rich context for understanding the functions of genes implicated in hearing loss. This chapter focuses on molecular mechanisms of inner ear development derived from studies of model organisms.

  15. Fourteen-years experience with cochlear implantation in Ramathibodi Hospital.

    Science.gov (United States)

    Kasemsuwan, Lalida; Cheewaruangroj, Wichit; Tungkeeratichai, Jumroon; Bhongmakapat, Thongchai; Thawin, Cheamchit; Lertsukprasert, Krisna; Tiravanitchakul, Rattinan; Dara, Rada; Laothamatas, Jiraporn

    2010-12-01

    To review the cochlear implant program in Ramathibodi Hospital and share experience of cochlear implantation emphasized on clinical and surgical outcomes. Retrospective review of 143 ears (140 patients) operated with cochlear implant between 1995 and 2009. The demographic data including etiology of deafness and findings from temporal bone CTscans were reviewed. The authors' experience with cochlear implant surgery in terms of patient selection, patient advisory clinic, necessary equipment, pre- and postoperative evaluations, surgical techniques and complications were discussed. Most congenital origin was unknown etiology and congenital rubella was the most common known cause. From the CT scans of congenital deafness, vestibular aqueduct dilatation was the most common and found in 29.31% while Mondini malformation was shown to be 16.37%. The authors' surgical technique of using the pocket method and designed bony ridge at cortical mastoid rim had helped stabilizing the implant and electrode fancoil. During the last two years, no complication or revision surgery was detected. Cochlear implant surgery in both children and adults can result in good surgical outcome and fewer complications under experienced surgeons and a good team.

  16. Ear Infection and Vaccines

    Science.gov (United States)

    ... an ENT Doctor Near You Ear Infection and Vaccines Ear Infection and Vaccines Patient Health Information News ... or may need reinsertion over time. What about vaccines? A vaccine is a preparation administered to stimulate ...

  17. External Otitis (Swimmer's Ear)

    Science.gov (United States)

    ... Abbreviations Weights & Measures ENGLISH View Professional English Deutsch Japanese Espaniol Find information on medical topics, symptoms, drugs, ... A doctor's examination of the ear canal Sometimes culture of a sample from the ear canal The ...

  18. COCHLEAR IMPLANTATION: MY EXPERIENCE

    OpenAIRE

    Shankar

    2015-01-01

    Cochlear implant is a small, surgically implanted complex electronic device that can help to provide a sense of sound to a person with severe to profound sensorineural hearing loss. This type of hearing loss, typically involves damage to hair cells in the cochlea, as a result sound cannot reach the auditory nerve which usually receives information from hair cells. A cochlear implant skips the damaged hair cells and to stimulate the auditory nerve directly. An implant does not rest...

  19. NANOCI-Nanotechnology Based Cochlear Implant With Gapless Interface to Auditory Neurons.

    Science.gov (United States)

    Senn, Pascal; Roccio, Marta; Hahnewald, Stefan; Frick, Claudia; Kwiatkowska, Monika; Ishikawa, Masaaki; Bako, Peter; Li, Hao; Edin, Fredrik; Liu, Wei; Rask-Andersen, Helge; Pyykkö, Ilmari; Zou, Jing; Mannerström, Marika; Keppner, Herbert; Homsy, Alexandra; Laux, Edith; Llera, Miguel; Lellouche, Jean-Paul; Ostrovsky, Stella; Banin, Ehud; Gedanken, Aharon; Perkas, Nina; Wank, Ute; Wiesmüller, Karl-Heinz; Mistrík, Pavel; Benav, Heval; Garnham, Carolyn; Jolly, Claude; Gander, Filippo; Ulrich, Peter; Müller, Marcus; Löwenheim, Hubert

    2017-09-01

    : Cochlear implants (CI) restore functional hearing in the majority of deaf patients. Despite the tremendous success of these devices, some limitations remain. The bottleneck for optimal electrical stimulation with CI is caused by the anatomical gap between the electrode array and the auditory neurons in the inner ear. As a consequence, current devices are limited through 1) low frequency resolution, hence sub-optimal sound quality and 2), large stimulation currents, hence high energy consumption (responsible for significant battery costs and for impeding the development of fully implantable systems). A recently completed, multinational and interdisciplinary project called NANOCI aimed at overcoming current limitations by creating a gapless interface between auditory nerve fibers and the cochlear implant electrode array. This ambitious goal was achieved in vivo by neurotrophin-induced attraction of neurites through an intracochlear gel-nanomatrix onto a modified nanoCI electrode array located in the scala tympani of deafened guinea pigs. Functionally, the gapless interface led to lower stimulation thresholds and a larger dynamic range in vivo, and to reduced stimulation energy requirement (up to fivefold) in an in vitro model using auditory neurons cultured on multi-electrode arrays. In conclusion, the NANOCI project yielded proof of concept that a gapless interface between auditory neurons and cochlear implant electrode arrays is feasible. These findings may be of relevance for the development of future CI systems with better sound quality and performance and lower energy consumption. The present overview/review paper summarizes the NANOCI project history and highlights achievements of the individual work packages.

  20. Three challenges for future research on cochlear implants

    Directory of Open Access Journals (Sweden)

    David B. Pisoni

    2017-12-01

    which specific biological and neurocognitive factors are responsible for individual differences or understanding the underlying sensory and neurocognitive basis for variability in performance, it is impossible to select a specific approach to habilitation after a deaf adult or child receives a CI. Deaf adults and children who are performing poorly with their CIs are not a homogeneous group and may differ in many different ways from each other, reflecting the dysfunction of multiple brain systems associated with both congenital and acquired deafness. Hearing loss is not only an ear issue, it is also a brain issue too reflecting close links between perception and action and brain, body and world working together as a functionally integrated information processing system to support robust speech recognition and spoken language processing after implantation. Keywords: Hearing loss, Cochlear implants, Outcomes following implantation

  1. Evaluation of the Slope of Amplitude Growth Function Changes of the Electrically Evoked Action Potential in Three Months after Receiving the Device in Children with Cochlear Implant

    Directory of Open Access Journals (Sweden)

    Ali Reza Pourjavid

    2012-04-01

    Full Text Available Objective: In neural response telemetry, intracochlear electrodes stimulate the auditory nerve and record the neural responses. The electrical stimulation is sent to the auditory nerve by an electrode and the resulted response, called electrically evoked compound action potential, is recorded by an adjacent electrode. The most important clinical applications of this test are evaluation and monitoring the intra and postoperative responses of auditory nerve and help to primary setting of speech processor. The aim of this study was evaluating the potential's slope of amplitude growth function changes three monthes after receiving the devise in pediatric cochlear implant recipients. Materials & Methods: This longitudinal study evaluated the potentials' slope of amplitude growth function changes in four given electrodes in four sessions after receiving the devise by approximately one month's intervals in all of the children who implanted in Amir Alam and Hazrat-e-Rasoul hospitals in 2007, July to December. Friedman test was used to analyse the results. Results: Electrically evoked compound action potential's mean slope of each electrode was more in later sessions relative to first session, while there was significant difference between the 1st and the other electrodes’ responses in every session (P<0.05. Conclusion: The reliabiliy of the responses results in more assurance of clinician to fit the speech processor for along time. Better responses in apical electrodes may lead to develope an effective coding strategy.

  2. A COMPARISON OF TWO DIFFERENT DOSES OF DEXMEDETOMIDINE INFUSION DURING MAINTENANCE OF GENERAL ANAESTHESIA IN PATIENTS UNDERGOING SPINE SURGERIES, FUNCTIONAL ENDOSCOPIC SINUS SURGERY AND MIDDLE EAR SURGERIES

    Directory of Open Access Journals (Sweden)

    Bijay

    2016-03-01

    Full Text Available BACKGROUND This study is undertaken to compare the hemodynamic effects and reduction in the doses of volatile anaesthetics and muscle relaxants using two different doses of dexmedetomidine infusion during maintenance of anaesthesia in spine, functional endoscopic sinus surgery and middle ear surgeries. METHODS Sixty patients are randomly divided into 2 groups of 30 each. After shifting to the operation theatre baseline vitals were recorded. Anesthesia induced with thiopentone sodium and intubation done with the help of succinylcholine and maintained with oxygen, nitrous oxide and isoflurane. After 1 min of intubation, maintenance infusion of dexmedetomidine (0.4 mcg/kg/hr and 0.7 mcg/kg/hr for patients allotted in 2 separate groups was started and stopped 15 min before end of surgery. Hemodynamic parameters and any reduction in the doses of volatile anaesthetics and muscle relaxants was noted. RESULTS Dexmedetomidine infusion (0.4 mcg/kg/hr and 0.7 mcg/kg/hr in both groups reduced the requirements of muscle relaxants and volatile anaesthetics. Hemodynamic stability was better in the group receiving 0.4 mcg/kg/hr. Patients receiving 0.7 mcg/kg/hr had higher incidence of hypotension, bradycardia and delayed emergence from anaesthesia. CONCLUSION Dexmedetomidine infusion at 0.4 mcg/kg/hr during maintenance of anaesthesia in spine surgery, FESS and middle ear surgery would be good option to reduce the requirements of volatile anaesthetics, muscle relaxants and for better hemodynamic stability. OBJECTIVE OF STUDY: Primary Objective To compare and evaluate the hemodynamic effects and reduction in requirements of volatile anaesthetics and muscle relaxants with two different doses of dexmedetomidine infusion during maintenance of general anaesthesia in patients undergoing spine, FESS and middle ear surgeries.

  3. Swimmer's Ear (External Otitis)

    Science.gov (United States)

    ... Body Mind Sexual Health Food & Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español ... español Otitis del nadador (otitis externa) What Is Swimmer's Ear? Swimmer's ear is an infection of the ear canal, the tubular opening that ...

  4. Benefits and detriments of unilateral cochlear implant use on bilateral auditory development in children who are deaf

    OpenAIRE

    Karen A. Gordon; Karen A. Gordon; Karen A. Gordon; Salima eJiwani; Salima eJiwani; Blake ePapsin; Blake ePapsin

    2013-01-01

    We have explored both the benefits and detriments of providing electrical input through a cochlear implant in one ear to the auditory system of young children. A cochlear implant delivers electrical pulses to stimulate the auditory nerve, providing children who are deaf with access to sound. The goals of implantation are to restrict reorganization of the deprived immature auditory brain and promote development of hearing and spoken language. It is clear that limiting the duration of deprivati...

  5. Interaural Place-Mismatch Estimation With Two-Formant Vowels in Unilateral Cochlear- Implant Users

    DEFF Research Database (Denmark)

    Guérit, François; Santurette, Sébastien; Chalupper, Josef

    Background: For patients with one cochlear implant (CI) and residual hearing in the opposite ear, a default frequency-to-electrode map is typically used despite large individual differences in electrode-array insertion depth. This non-individualized fitting rationale might partly explain the vari...

  6. Contrast enhancement of the cochlear aqueduct in MR imaging: its frequency and clinical significance

    International Nuclear Information System (INIS)

    Nakamura, T.; Naganawa, S.; Fukatsu, H.; Sakurai, Y.; Ishigaki, T.; Aoki, I.; Ninomiya, A.; Nakashima, T.

    2003-01-01

    There have been no previous reports on contrast enhancement of the cochlear aqueduct in magnetic resonance imaging. The purpose of the present study was to evaluate the frequency and significance of this finding. Thirty-one patients (15 men and 16 women; age range 18-81 years) with otologic symptoms (sudden sensorineural hearing loss, vertigo, or tinnitus) were examined using contrast-enhanced imaging on a 1.5-T MR scanner. The normal ear served as the control. Two radiologists evaluated contrast enhancement in the area of the cochlear aqueduct. Forty-eight of 62 ears (77.4%) showed contrast enhancement of the cochlear aqueduct, but no significant differences in the frequency of contrast enhancement were observed between patients with and patients without vertigo, tinnitus, sensorineural hearing loss, cerebellopontine angle tumors, or a high-riding jugular bulb. In addition, no gender- or age-related differences were noted. Contrast enhancement of the cochlear aqueduct was frequently observed, but the frequency of enhancement in symptomatic ears was not significantly higher than in control ears. The results of this study may prove helpful in avoiding unnecessary examinations and potential diagnostic confusion. (orig.)

  7. Contrast enhancement of the cochlear aqueduct in MR imaging: its frequency and clinical significance

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, T.; Naganawa, S.; Fukatsu, H.; Sakurai, Y.; Ishigaki, T. [Department of Radiology, Nagoya University School of Medicine, 65 Tsurumai-cho, 466-8550, Shouwa-ku, Nagoya (Japan); Aoki, I.; Ninomiya, A. [Medical Systems Company, Toshiba Corporation, Nasu Operations, Otawara-shi, Tochigi (Japan); Nakashima, T. [Department of Otorhinolaryngology, Nagoya University School of Medicine, Shouwa-ku, Nagoya (Japan)

    2003-09-01

    There have been no previous reports on contrast enhancement of the cochlear aqueduct in magnetic resonance imaging. The purpose of the present study was to evaluate the frequency and significance of this finding. Thirty-one patients (15 men and 16 women; age range 18-81 years) with otologic symptoms (sudden sensorineural hearing loss, vertigo, or tinnitus) were examined using contrast-enhanced imaging on a 1.5-T MR scanner. The normal ear served as the control. Two radiologists evaluated contrast enhancement in the area of the cochlear aqueduct. Forty-eight of 62 ears (77.4%) showed contrast enhancement of the cochlear aqueduct, but no significant differences in the frequency of contrast enhancement were observed between patients with and patients without vertigo, tinnitus, sensorineural hearing loss, cerebellopontine angle tumors, or a high-riding jugular bulb. In addition, no gender- or age-related differences were noted. Contrast enhancement of the cochlear aqueduct was frequently observed, but the frequency of enhancement in symptomatic ears was not significantly higher than in control ears. The results of this study may prove helpful in avoiding unnecessary examinations and potential diagnostic confusion. (orig.)

  8. Analog Integrated Circuit and System Design for a Compact, Low-Power Cochlear Implant

    NARCIS (Netherlands)

    Ngamkham, W.

    2015-01-01

    Cochlear Implants (CIs) are prosthetic devices that restore hearing in profoundly deaf patients by bypassing the damaged parts of the inner ear and directly stimulating the remaining auditory nerve fibers in the cochlea with electrical pulses. This thesis describs the electronic circuit design of

  9. Semiautomatic Cochleostomy Target and Insertion Trajectory Planning for Minimally Invasive Cochlear Implantation

    Directory of Open Access Journals (Sweden)

    Wilhelm Wimmer

    2014-01-01

    Full Text Available A major component of minimally invasive cochlear implantation is atraumatic scala tympani (ST placement of the electrode array. This work reports on a semiautomatic planning paradigm that uses anatomical landmarks and cochlear surface models for cochleostomy target and insertion trajectory computation. The method was validated in a human whole head cadaver model (n=10 ears. Cochleostomy targets were generated from an automated script and used for consecutive planning of a direct cochlear access (DCA drill trajectory from the mastoid surface to the inner ear. An image-guided robotic system was used to perform both, DCA and cochleostomy drilling. Nine of 10 implanted specimens showed complete ST placement. One case of scala vestibuli insertion occurred due to a registration/drilling error of 0.79 mm. The presented approach indicates that a safe cochleostomy target and insertion trajectory can be planned using conventional clinical imaging modalities, which lack sufficient resolution to identify the basilar membrane.

  10. A Binaural Cochlear Implant Sound Coding Strategy Inspired by the Contralateral Medial Olivocochlear Reflex.

    Science.gov (United States)

    Lopez-Poveda, Enrique A; Eustaquio-Martín, Almudena; Stohl, Joshua S; Wolford, Robert D; Schatzer, Reinhold; Wilson, Blake S

    2016-01-01

    In natural hearing, cochlear mechanical compression is dynamically adjusted via the efferent medial olivocochlear reflex (MOCR). These adjustments probably help understanding speech in noisy environments and are not available to the users of current cochlear implants (CIs). The aims of the present study are to: (1) present a binaural CI sound processing strategy inspired by the control of cochlear compression provided by the contralateral MOCR in natural hearing; and (2) assess the benefits of the new strategy for understanding speech presented in competition with steady noise with a speech-like spectrum in various spatial configurations of the speech and noise sources. Pairs of CI sound processors (one per ear) were constructed to mimic or not mimic the effects of the contralateral MOCR on compression. For the nonmimicking condition (standard strategy or STD), the two processors in a pair functioned similarly to standard clinical processors (i.e., with fixed back-end compression and independently of each other). When configured to mimic the effects of the MOCR (MOC strategy), the two processors communicated with each other and the amount of back-end compression in a given frequency channel of each processor in the pair decreased/increased dynamically (so that output levels dropped/increased) with increases/decreases in the output energy from the corresponding frequency channel in the contralateral processor. Speech reception thresholds in speech-shaped noise were measured for 3 bilateral CI users and 2 single-sided deaf unilateral CI users. Thresholds were compared for the STD and MOC strategies in unilateral and bilateral listening conditions and for three spatial configurations of the speech and noise sources in simulated free-field conditions: speech and noise sources colocated in front of the listener, speech on the left ear with noise in front of the listener, and speech on the left ear with noise on the right ear. In both bilateral and unilateral listening

  11. Development of the inner ear.

    Science.gov (United States)

    Whitfield, Tanya T

    2015-06-01

    The vertebrate inner ear is a sensory organ of exquisite design and sensitivity. It responds to sound, gravity and movement, serving both auditory (hearing) and vestibular (balance) functions. Almost all cell types of the inner ear, including sensory hair cells, sensory neurons, secretory cells and supporting cells, derive from the otic placode, one of the several ectodermal thickenings that arise around the edge of the anterior neural plate in the early embryo. The developmental patterning mechanisms that underlie formation of the inner ear from the otic placode are varied and complex, involving the reiterative use of familiar signalling pathways, together with roles for transcription factors, transmembrane proteins, and extracellular matrix components. In this review, I have selected highlights that illustrate just a few of the many recent discoveries relating to the development of this fascinating organ system. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Dynamic changes in the inner ear function and vestibular neural pathway related to the progression of labyrinthine infarction in patient with an anterior inferior cerebellar artery infarction.

    Science.gov (United States)

    Kim, Duk Rim; Lee, Hyo-Jeong; Kim, Hyung-Jong; Hong, Sung Kwang

    2011-12-01

    To describe changes in the inner ear function and the vestibular neural pathway according to the progression of a labyrinthine infarction in a patient with an anterior inferior cerebellar artery (AICA) infarction. A 58-year-old woman with hypertension who presented with isolated inner ear symptoms similar to those of endolymphatic hydrops but finally progressed to an AICA infarction. Serial neurotologic testing according to progression to an AICA infarction and antiplatelet therapy. Radiologic findings and neurotologic parameters, including pure tone audiogram thresholds, spontaneous nystagmus, summating potentials/action potentials on electrocochleography, interaural amplitude difference on the vestibular-evoked myogenic potential test, canal paresis and fixation index on the bithermal caloric test, and gain on oculomotor tests. Our patient initially presented with sudden hearing loss and was diagnosed with an acute AICA infarction on a follow up MRI. Dynamic change in neurotologic testing was observed during disease progression. The vertigo and motion intolerance improved gradually after antiplatelet therapy. Changes in the clinical profile, which were documented during a transition from isolated labyrinthine ischemia to an AICA infarction, suggest that sensitivity to an ischemic injury is variable in different components of the labyrinthine organs in addition to providing a new insight into the response of vestibular neural pathway to ischemic injury.

  13. Mechanics of the frog ear

    NARCIS (Netherlands)

    Van Dijk, Pim; Mason, Matthew J.; Schoffelen, Richard L. M.; Narins, Peter M.; Meenderink, Sebastiaan W. F.

    The frog inner ear contains three regions that are sensitive to airborne sound and which are functionally distinct. (1) The responses of nerve fibres innervating the low-frequency, rostral part of the amphibian papilla (AP) are complex. Electrical tuning of hair cells presumably contributes to the

  14. cGMP-Prkg1 signaling and Pde5 inhibition shelter cochlear hair cells and hearing function.

    Science.gov (United States)

    Jaumann, Mirko; Dettling, Juliane; Gubelt, Martin; Zimmermann, Ulrike; Gerling, Andrea; Paquet-Durand, François; Feil, Susanne; Wolpert, Stephan; Franz, Christoph; Varakina, Ksenya; Xiong, Hao; Brandt, Niels; Kuhn, Stephanie; Geisler, Hyun-Soon; Rohbock, Karin; Ruth, Peter; Schlossmann, Jens; Hütter, Joachim; Sandner, Peter; Feil, Robert; Engel, Jutta; Knipper, Marlies; Rüttiger, Lukas

    2012-01-22

    Noise-induced hearing loss (NIHL) is a global health hazard with considerable pathophysiological and social consequences that has no effective treatment. In the heart, lung and other organs, cyclic guanosine monophosphate (cGMP) facilitates protective processes in response to traumatic events. We therefore analyzed NIHL in mice with a genetic deletion of the gene encoding cGMP-dependent protein kinase type I (Prkg1) and found a greater vulnerability to and markedly less recovery from NIHL in these mice as compared to mice without the deletion. Prkg1 was expressed in the sensory cells and neurons of the inner ear of wild-type mice, and its expression partly overlapped with the expression profile of cGMP-hydrolyzing phosphodiesterase 5 (Pde5). Treatment of rats and wild-type mice with the Pde5 inhibitor vardenafil almost completely prevented NIHL and caused a Prkg1-dependent upregulation of poly (ADP-ribose) in hair cells and the spiral ganglion, suggesting an endogenous protective cGMP-Prkg1 signaling pathway that culminates in the activation of poly (ADP-ribose) polymerase. These data suggest vardenafil or related drugs as possible candidates for the treatment of NIHL.

  15. Dynamics of inner ear pressure change caused by intracranial pressure manipulation in the guinea pig

    NARCIS (Netherlands)

    Thalen, EO; Wit, HP; Segenhout, JM; Albers, FWJ

    Previous studies have shown that pressure changes in the cerebrospinal fluid compartment are transmitted to the inner ear. The main route for pressure transfer is the cochlear aqueduct, about which little is known with regard to its dynamic properties. In the present study, sudden intracranial

  16. Inner ear malformations in siblings presenting with vestibular ...

    African Journals Online (AJOL)

    Although the association between inner ear abnormalities and progressive sensorineural hearing loss is well known, vestibular signs or loss of vestibular function in these ... We provide a brief overview of the latest classification of these inner ear defects as well as a review of the literature pertaining to children with inner ear ...

  17. Thyroid Hormone Receptors Control Developmental Maturation of the Middle Ear and the Size of the Ossicular Bones

    OpenAIRE

    Cordas, Emily A.; Ng, Lily; Hernandez, Arturo; Kaneshige, Masahiro; Cheng, Sheue-Yann; Forrest, Douglas

    2012-01-01

    Thyroid hormone is critical for auditory development and has well-known actions in the inner ear. However, less is known of thyroid hormone functions in the middle ear, which contains the ossicles (malleus, incus, stapes) that relay mechanical sound vibrations from the outer ear to the inner ear. During the later stages of middle ear development, prior to the onset of hearing, middle ear cavitation occurs, involving clearance of mesenchyme from the middle ear cavity while the immature cartila...

  18. Bone-anchored hearing aid (BAHA: indications, functional results, and comparison with reconstructive surgery of the ear

    Directory of Open Access Journals (Sweden)

    Bento, Ricardo Ferreira

    2012-01-01

    Full Text Available Introduction: The bone-anchored hearing aid (BAHA is a bone conduction hearing device that transmits sound directly into the inner ear. It is mainly used in patients with conductive hearing loss associated with aural atresia, but it is also used in those with mixed and sensorineural hearing loss. Goals: To review the main indications for BAHA, to analyze the audiometric results and its benefits for patients and compare them with other treatment modalities, and to compare the literature data with our sample of 13 patients. Method: The research was performed using a database covering works in English, Spanish, and Portuguese, with no limitations in the years when the procedures were performed. We compared the literature data with our results for the 13 patients who underwent BAHA implantation between the years 2000 and 2009. Results: Most of the studies showed that BAHA has great advantages over reconstructive surgery in terms of hearing results, complications, and disease recurrence. The postoperative results for our 13 patients were satisfactory and comparable with the results from the literature, with closure of the air-bone gap in 7 patients and achieving an air-bone gap of 10 dB in 6 patients. No postoperative complications were observed. Conclusion: BAHA is a better treatment option than reconstructive surgery for patients with bilateral deafness. It is a relatively simple surgical procedure with few complications and good hearing results. Recent studies have examined its use in conductive and unilateral sensorineural hearing loss.

  19. Bone-anchored hearing aid (BAHA): indications, functional results, and comparison with reconstructive surgery of the ear.

    Science.gov (United States)

    Bento, Ricardo Ferreira; Kiesewetter, Alessandra; Ikari, Liliane Satomi; Brito, Rubens

    2012-07-01

     The bone-anchored hearing aid (BAHA) is a bone conduction hearing device that transmits sound directly into the inner ear. It is mainly used in patients with conductive hearing loss associated with aural atresia, but it is also used in those with mixed and sensorineural hearing loss.  To review the main indications for BAHA, to analyze the audiometric results and its benefits for patients and compare them with other treatment modalities, and to compare the literature data with our sample of 13 patients.  The research was performed using a database covering works in English, Spanish, and Portuguese, with no limitations in the years when the procedures were performed. We compared the literature data with our results for the 13 patients who underwent BAHA implantation between the years 2000 and 2009.  Most of the studies showed that BAHA has great advantages over reconstructive surgery in terms of hearing results, complications, and disease recurrence. The postoperative results for our 13 patients were satisfactory and comparable with the results from the literature, with closure of the air-bone gap in 7 patients and achieving an air-bone gap of 10 dB in 6 patients. No postoperative complications were observed.  BAHA is a better treatment option than reconstructive surgery for patients with bilateral deafness. It is a relatively simple surgical procedure with few complications and good hearing results. Recent studies have examined its use in conductive and unilateral sensorineural hearing loss.

  20. Bioinformatic Integration of Molecular Networks and Major Pathways Involved in Mice Cochlear and Vestibular Supporting Cells.

    Science.gov (United States)

    Requena, Teresa; Gallego-Martinez, Alvaro; Lopez-Escamez, Jose A

    2018-01-01

    Background : Cochlear and vestibular epithelial non-hair cells (ENHCs) are the supporting elements of the cellular architecture in the organ of Corti and the vestibular neuroepithelium in the inner ear. Intercellular and cell-extracellular matrix interactions are essential to prevent an abnormal ion redistribution leading to hearing and vestibular loss. The aim of this study is to define the main pathways and molecular networks in the mouse ENHCs. Methods : We retrieved microarray and RNA-seq datasets from mouse epithelial sensory and non-sensory cells from gEAR portal (http://umgear.org/index.html) and obtained gene expression fold-change between ENHCs and non-epithelial cells (NECs) against HCs for each gene. Differentially expressed genes (DEG) with a log2 fold change between 1 and -1 were discarded. The remaining genes were selected to search for interactions using Ingenuity Pathway Analysis and STRING platform. Specific molecular networks for ENHCs in the cochlea and the vestibular organs were generated and significant pathways were identified. Results : Between 1723 and 1559 DEG were found in the mouse cochlear and vestibular tissues, respectively. Six main pathways showed enrichment in the supporting cells in both tissues: (1) "Inhibition of Matrix Metalloproteases"; (2) "Calcium Transport I"; (3) "Calcium Signaling"; (4) "Leukocyte Extravasation Signaling"; (5) "Signaling by Rho Family GTPases"; and (6) "Axonal Guidance Si". In the mouse cochlea, ENHCs showed a significant enrichment in 18 pathways highlighting "axonal guidance signaling (AGS)" ( p = 4.37 × 10 -8 ) and "RhoGDI Signaling" ( p = 3.31 × 10 -8 ). In the vestibular dataset, there were 20 enriched pathways in ENHCs, the most significant being "Leukocyte Extravasation Signaling" ( p = 8.71 × 10 -6 ), "Signaling by Rho Family GTPases" ( p = 1.20 × 10 -5 ) and "Calcium Signaling" ( p = 1.20 × 10 -5 ). Among the top ranked networks, the most biologically significant network contained the

  1. Comparison of f2/f1 ratio functions in rabbit and gerbil: Ear-canal DPOAEs vs noninvasively inferred intracochlear DPs

    Science.gov (United States)

    Martin, Glen K.; Stagner, Barden B.; Dong, Wei; Lonsbury-Martin, Brenda L.

    2015-12-01

    The properties of distortion product otoacoustic emissions (DPOAEs), i.e., distortion products (DPs) measured in the ear canal, have been thoroughly described. However, considerably less is known about the behavior of intracochlear DPs (iDPs). Detailed comparisons of DPOAEs to iDPs would provide valuable insights on the extent to which ear-canal DPOAEs mirror iDPs. Prior studies described a technique whereby the behavior of iDPs could be inferred by interacting a probe tone (f3) with the iDP of interest to produce a `secondary' DPOAE (DPOAÉ). The behavior of DPOAÉ was then used to deduce the characteristics of the iDP. In the present study, this method was used in rabbits and gerbils to simultaneously compare DPOAE f2/f1-ratio functions to their iDP counterparts. The 2f1-f2 and 2f2-f1 DPOAEs were collected with f1 and f2 primary-tone levels varied from 35-75 dB SPL, and with a 50-dB SPL f3 placed at a DP/f3 ratio of 1.25 to evoke a DPOAÉ at 2f3-(2f1-f2) or 2f3-(2f2-f1). Control experiments demonstrated little effect of the f3-probe tone on DPOAE-ratio functions. Substitution experiments were performed to determine any suppressive effects of the f1 and f2 primaries on the generation of DPOAÉ, as well as to infer the intracochlear level of the iDP once the DPOAÉ was corrected for suppression. Results showed that at low primary-tone levels, 2f1-f2 DPOAE f2/f1-ratio functions peaked around f2/f1=1.25, and exhibited an inverted U-shaped function. In contrast, simultaneously measured 2f1-f2 iDP-ratio functions peaked at f2/f1≈1. Similar growth of the inferred iDP was obtained for higher-level primaries when the ratio functions were corrected for suppressive effects. At these higher levels, DPOAE-ratio functions leveled off and no longer showed the steep reduction at narrow f2/f1 ratios. Overall, noninvasive estimates of 2f1-f2 iDP-ratio functions agreed with reports of similar functions directly measured for 2f1-f2 DPs on the basilar membrane (BM) or in

  2. Round window closure affects cochlear responses to suprathreshold stimuli.

    Science.gov (United States)

    Cai, Qunfeng; Whitcomb, Carolyn; Eggleston, Jessica; Sun, Wei; Salvi, Richard; Hu, Bo Hua

    2013-12-01

    The round window acts as a vent for releasing inner ear pressure and facilitating basilar membrane vibration. Loss of this venting function affects cochlear function, which leads to hearing impairment. In an effort to identify functional changes that might be used in clinical diagnosis of round window atresia, the current investigation was designed to examine how the cochlea responds to suprathreshold stimuli following round window closure. Prospective, controlled, animal study. A rat model of round window occlusion (RWO) was established. With this model, the thresholds of auditory brainstem responses (ABR) and the input/output (IO) functions of distortion product otoacoustic emissions (DPOAEs) and acoustic startle responses were examined. Round window closure caused a mild shift in the thresholds of the auditory brainstem response (13.5 ± 9.1 dB). It also reduced the amplitudes of the distortion product otoacoustic emissions and the slope of the input/output functions. This peripheral change was accompanied by a significant reduction in the amplitude, but not the threshold, of the acoustic startle reflex, a motor response to suprathreshold sounds. In addition to causing mild increase in the threshold of the auditory brainstem response, round window occlusion reduced the slopes of both distortion product otoacoustic emissions and startle reflex input/output functions. These changes differ from those observed for typical conductive or sensory hearing loss, and could be present in patients with round window atresia. However, future clinical observations in patients are needed to confirm these findings. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

  3. [Diagnostic significance of multi-slice computed tomography imaging in congenital inner ear malformations].

    Science.gov (United States)

    Ma, Hui; Han, Ping; Liang, Bo; Liu, Fang; Tian, Zhi-Liang; Lei, Zi-Qiao; Li, You-Lin; Kong, Wei-Jia

    2005-04-01

    To evaluate the feasibility and usability of multi-slice computed tomography (MSCT) in congenital inner ear malformations. Fourty-four patients with sensorineural hearing loss (SNHL) were examined by a Somatom Sensation 16 (siemens, Germany) CT scanner with following parameters: 120 kV, 100 mAs, 0.75 mm collimation, 1 mm reconstruction increment, a pitch factor of 1 and a field of view of 100 mm. The axial images of interested ears were reconstructed with 0.1 mm reconstruction increment, and a field of view of 50 mm. The 3D reconstructions were done with volume rendering technique (VRT) on the workstation (3D Virtuoso and Wizard,siemens). Twenty-five patients were normal and 19 patients (36 ears) were congenital inner ear malformations among 44 patients scanned with MSCT. Of the malformations, all the axial, MPR and VRT images can display the site and degree in 33 ears. VRT images were superior to the axial images in displaying the malformations in 3 ears with the small lateral semicircular canal malformations. The malformations were Michel deformity (1 ear), common cavity deformity (3 ears), incomplete partition I (3 ears), incomplete partition II (Mondini deformity, 5 ears), vestibular and semicircular canal malformations( 14 ears), vestibular aqueduct dilate( 16 ears, of which 6 ears accompanied by other malformations), the internal auditory canal malformation(8 ears, all accompanied by other malformations). MSCT allows a comprehensively assessing various congenital ear malformations through high quality MPR and VRT reconstructions. VRT images can display the site and degree of the malformations three-dimensionally and intuitionisticly. It is very useful to the cochlear implantation.

  4. Middle Ear Infections (For Parents)

    Science.gov (United States)

    ... happen when viruses or bacteria get into the middle ear, the space behind the eardrum. When a child has an ear infection (also called otitis media ), ... down can cause painful pressure changes in the middle ear. Older kids can complain about ear pain, but a younger child might just tug at the ear or be ...

  5. Pneumococcal meningitis post-cochlear implantation: preventative measures.

    Science.gov (United States)

    Wei, Benjamin P C; Shepherd, Robert K; Robins-Browne, Roy M; Clark, Graeme M; O'Leary, Stephen J

    2010-11-01

    Both clinical data and laboratory studies demonstrated the risk of pneumococcal meningitis post-cochlear implantation. This review examines strategies to prevent post-implant meningitis. Medline/PubMed database; English articles after 1980. Search terms: cochlear implants, pneumococcus meningitis, streptococcus pneumonia, immunization, prevention. Narrative review. All articles relating to post-implant meningitis without any restriction in study designs were assessed and information extracted. The presence of inner ear trauma as a result of surgical technique or cochlear implant electrode array design was associated with a higher risk of post-implant meningitis. Laboratory data demonstrated the effectiveness of pneumococcal vaccination in preventing meningitis induced via the hematogenous route of infection. Fibrous sealing around the electrode array at the cochleostomy site, and the use of antibiotic-coated electrode array reduced the risk of meningitis induced via an otogenic route. The recent scientific data support the U.S. Food and Drug Administration recommendation of pneumococcal vaccination for the prevention of meningitis in implant recipients. Nontraumatic cochlear implant design, surgical technique, and an adequate fibrous seal around the cochleostomy site further reduce the risk of meningitis. Copyright © 2010 American Academy of Otolaryngology–Head and Neck Surgery Foundation. Published by Mosby, Inc. All rights reserved.

  6. Benefits and Risks of Cochlear Implants

    Science.gov (United States)

    ... music. Some enjoy the sound of certain instruments (piano or guitar, for example) and certain voices. Others ... in Cochlear Implants What is a Cochlear Implant? Benefits and Risks of Cochlear Implants Frequently Asked Questions ...

  7. A Tool for Assessing Functional Use of Audition in Children: Results in Children with the MED-EL COMBI 40+ Cochlear Implant System

    Science.gov (United States)

    Franz, Darla C.; Caleffe-Schenck, Nancy; Kirk, Karen Iler

    2004-01-01

    An instrument for measuring and tracking changes in auditory skill development over time was developed for use with a group of children with profound deafness who received a MED-EL COMBI 40+ cochlear implant. The aim of this paper is to describe the use of this instrument, the "Checklist of Auditory Communication Skills", and to present results…

  8. Inner ear anatomy in Waardenburg syndrome: radiological assessment and comparison with normative data.

    Science.gov (United States)

    Kontorinis, Georgios; Goetz, Friedrich; Lanfermann, Heinrich; Luytenski, Stefan; Giesemann, Anja M

    2014-08-01

    As patients with Waardenburg syndrome (WS) represent potential candidates for cochlear implantation, their inner ear anatomy is of high significance. There is an ongoing debate whether WS is related to any inner ear dysplasias. Our objective was to evaluate radiologically the inner ear anatomy in patients with WS and identify any temporal bone malformations. A retrospective case review was carried out in a tertiary, referral center. The high resolution computed tomography (HRCT) scans of the temporal bone from 20 patients (40 ears) with WS who were managed for deafness in a tertiary referral center from 1995 to 2012 were retrospectively examined. Measurements of 15 different inner ear dimensions, involving the cochlea, the vestibule, the semicircular canals and the internal auditory meatus, as well as measurements of the vestibular aqueduct, were performed independently by two neuroradiologists. Finally, we compared the results from the WS group with a control group consisting of 50 normal hearing subjects (100 ears) and with previously reported normative values. Inner ear malformations were not found in any of the patients with WS. All measured inner ear dimensions were within the normative values compiled by our study group as well as by others. Inner ear malformations are not characteristic for all types of WS; however, certain rare subtypes might be related to inner ear deformities. Normative cochleovestibular dimensions that can help in assessing the temporal bone anatomy are provided. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  9. The role of MRI in suspected inner ear malformations; Stellenwert der MRT bei Verdacht auf Innenohrmissbildung

    Energy Technology Data Exchange (ETDEWEB)

    Koesling, S.; Juettemann, S.; Amaya, B. [Halle-Wittenberg Univ., Halle (Germany). Klinik fuer Diagnostische Radiologie; Rasinski, C.; Bloching, M. [Halle-Wittenberg Univ., Halle (Germany). Klinik fuer Hals-, Nasen-, Ohrenkrankheiten; Koenig, E. [Leipzig Univ. (Germany). Klinik fuer Hals-, Nasen-, Ohrenkrankheiten

    2003-12-01

    Purpose: This is a prospective analysis of the value of MRI in suspected inner ear malformations. Materials and Methods: In 50 patients (43 children and young adults, 7 adults) with suspected inner ear malformation MRI (1.5 T) was performed. In addition, 42 of these patients underwent CT. For the analysis of the inner ear structures, the constructive interference in steady state (CISS) sequence with 0.7 mm slice thickness was used. Functional tests revealed a sensorineural hearing loss or deafness in 82 temporal bones (TB) and a combined hearing loss in 4 TB. The hearing loss was unilateral in 14 patients. MRI and CT findings were compared. Results: Imaging findings were normal in 58 TB. The pathological findings included inner ear malformations (35 TB), inflammatory changes (4 TB), partial obliteration of labyrinth (2 TB) and congenital aural atresia (1 TB). An isolated absence of the cochlear nerve (1 TB) could only be found by MRI. In the remaining cases, an inner ear malformation was diagnosed by MRI and CT with the same confidence but MRI was superior in displaying the fine details. Conclusions: MRI will become the method of choice in the diagnosis of inner ear malformations. (orig.) [German] Ziel: Das Ziel der Arbeit bestand in einer prospektiven Analyse des Stellenwertes der MRT bei Verdacht auf eine Innenohrmissbildung. Material und Methodik: 50 Patienten (43 Kinder und Jugendliche, 7 Erwachsene) mit dringendem Verdacht auf eine Innenohrmissbildung erhielten eine MRT-Untersuchung (1,5 T), bei 42 dieser Patienten wurde auch eine CT durchgefuehrt. Bei der Beurteilung der Innenohrstrukturen kam die CISS-Sequenz mit einer Schichtdicke von 0,7 mm zur Anwendung. Durch Funktionstests wurde an 82 Schlaefenbeinen (SB) eine Innenohrhoerstoerung und an 4 SB eine kombinierte Hoerstoerung diagnostiziert. 14 Patienten hatten eine einseitige Hoerstoerung. MRT- und CT-Ergebnisse wurden verglichen. Ergebnisse: Einen bildgebenden Normalbefund wiesen 58 SB auf. Folgende

  10. Bioinformatic Integration of Molecular Networks and Major Pathways Involved in Mice Cochlear and Vestibular Supporting Cells

    Directory of Open Access Journals (Sweden)

    Teresa Requena

    2018-04-01

    Full Text Available Background: Cochlear and vestibular epithelial non-hair cells (ENHCs are the supporting elements of the cellular architecture in the organ of Corti and the vestibular neuroepithelium in the inner ear. Intercellular and cell-extracellular matrix interactions are essential to prevent an abnormal ion redistribution leading to hearing and vestibular loss. The aim of this study is to define the main pathways and molecular networks in the mouse ENHCs.Methods: We retrieved microarray and RNA-seq datasets from mouse epithelial sensory and non-sensory cells from gEAR portal (http://umgear.org/index.html and obtained gene expression fold-change between ENHCs and non-epithelial cells (NECs against HCs for each gene. Differentially expressed genes (DEG with a log2 fold change between 1 and −1 were discarded. The remaining genes were selected to search for interactions using Ingenuity Pathway Analysis and STRING platform. Specific molecular networks for ENHCs in the cochlea and the vestibular organs were generated and significant pathways were identified.Results: Between 1723 and 1559 DEG were found in the mouse cochlear and vestibular tissues, respectively. Six main pathways showed enrichment in the supporting cells in both tissues: (1 “Inhibition of Matrix Metalloproteases”; (2 “Calcium Transport I”; (3 “Calcium Signaling”; (4 “Leukocyte Extravasation Signaling”; (5 “Signaling by Rho Family GTPases”; and (6 “Axonal Guidance Si”. In the mouse cochlea, ENHCs showed a significant enrichment in 18 pathways highlighting “axonal guidance signaling (AGS” (p = 4.37 × 10−8 and “RhoGDI Signaling” (p = 3.31 × 10−8. In the vestibular dataset, there were 20 enriched pathways in ENHCs, the most significant being “Leukocyte Extravasation Signaling” (p = 8.71 × 10−6, “Signaling by Rho Family GTPases” (p = 1.20 × 10−5 and “Calcium Signaling” (p = 1.20 × 10−5. Among the top ranked networks, the most biologically

  11. Cochlear-Meningitis Vaccination

    Science.gov (United States)

    ... not routinely recommended for those 5 years of age or older, since most older children and adults are already immune to Hib. Available information does not suggest that older children and adults with cochlear implants require the Hib vaccine. However, the Hib vaccine ...

  12. Cochlear Implant Electrode Effect on Sound Energy Transfer Within the Cochlea During Acoustic Stimulation.

    Science.gov (United States)

    Greene, Nathaniel T; Mattingly, Jameson K; Jenkins, Herman A; Tollin, Daniel J; Easter, James R; Cass, Stephen P

    2015-09-01

    Cochlear implants (CIs) designed for hearing preservation will not alter mechanical properties of the middle and inner ears as measured by intracochlear pressure (P(IC)) and stapes velocity (Vstap). CIs designed to provide combined electroacoustic stimulation are now available. To maintain functional acoustic hearing, it is important to know if a CI electrode can alter middle or inner ear mechanics because any alteration could contribute to elevated low-frequency thresholds in electroacoustic stimulation patients. Seven human cadaveric temporal bones were prepared, and pure-tone stimuli from 120 Hz to 10 kHz were presented at a range of intensities up to 110 dB sound pressure level. P(IC) in the scala vestibuli (P(SV)) and tympani (PST) were measured with fiber-optic pressure sensors concurrently with VStap using laser Doppler vibrometry. Five CI electrodes from two different manufacturers with varying dimensions were inserted via a round window approach at six different depths (16-25 mm). The responses of P(IC) and VStap to acoustic stimulation were assessed as a function of stimulus frequency, normalized to sound pressure level in the external auditory canal, at baseline and electrode-inserted conditions. Responses measured with electrodes inserted were generally within approximately 5 dB of baseline, indicating little effect of CI electrode insertion on P(IC) and VStap. Overall, mean differences across conditions were small for all responses, and no substantial differences were consistently visible across electrode types. Results suggest that the influence of a CI electrode on middle and inner ear mechanics is minimal despite variation in electrode lengths and configurations.

  13. Measurement of cochlear length using the 'A' value for cochlea basal diameter: A feasibility study.

    Science.gov (United States)

    Deep, Nicholas L; Howard, Brittany E; Holbert, Sarah O; Hoxworth, Joseph M; Barrs, David M

    2017-07-01

    To determine whether the cochlea basal diameter (A value) measurement can be consistently and precisely obtained from high-resolution temporal bone imaging for use in cochlear length estimation. A feasibility study at a tertiary referral center was performed using the temporal bone CTs of 40 consecutive patients. The distance from the round window to the lateral wall was measured for each cochlea by two independent reviewers, a neuroradiologist and an otolaryngologist. The interrater reliability was calculated using the intraclass correlation coefficient (ICC) and the Bland-Altman plot. Forty patients (19 males, 21 females) for a total of 80 cochleae were included. Interrater reliability on the same ear had a high level of agreement by both the ICC and the Bland-Altman plot. ICCs were 0.90 (95% CI: 0.82, 0.94) for the left ear and 0.96 (95% CI: 0.92, 0.98) for the right ear. Bland-Altman plot confirmed interrater reliability with all 96% of measurements falling within the 95% limits of agreement. Measurement between the round window and lateral cochlear wall can be consistently and reliably obtained from high-resolution temporal bone CT scans. Thus, it is feasible to utilize this method to estimate the cochlear length of patients undergoing cochlear implantation.

  14. Cochlear neuropathy in human presbycusis: Confocal analysis of hidden hearing loss in post-mortem tissue.

    Science.gov (United States)

    Viana, Lucas M; O'Malley, Jennifer T; Burgess, Barbara J; Jones, Dianne D; Oliveira, Carlos A C P; Santos, Felipe; Merchant, Saumil N; Liberman, Leslie D; Liberman, M Charles

    2015-09-01

    Recent animal work has suggested that cochlear synapses are more vulnerable than hair cells in both noise-induced and age-related hearing loss. This synaptopathy is invisible in conventional histopathological analysis, because cochlear nerve cell bodies in the spiral ganglion survive for years, and synaptic analysis requires special immunostaining or serial-section electron microscopy. Here, we show that the same quadruple-immunostaining protocols that allow synaptic counts, hair cell counts, neuronal counts and differentiation of afferent and efferent fibers in mouse can be applied to human temporal bones, when harvested within 9 h post-mortem and prepared as dissected whole mounts of the sensory epithelium and osseous spiral lamina. Quantitative analysis of five "normal" ears, aged 54-89 yrs, without any history of otologic disease, suggests that cochlear synaptopathy and the degeneration of cochlear nerve peripheral axons, despite a near-normal hair cell population, may be an important component of human presbycusis. Although primary cochlear nerve degeneration is not expected to affect audiometric thresholds, it may be key to problems with hearing in noise that are characteristic of declining hearing abilities in the aging ear. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. 'Outrunning' the running ear

    African Journals Online (AJOL)

    Chantel

    acute purulent otitis media should be considered when evaluating a patient with a running ear.These are listed in Table I. To outrun the running ear all these facts should be kept in mind when evaluating a patient. HISTORY. Some important questions to ask, are: • Family history. • cystic fibrosis. • allergies — nasal, chest and.

  16. External Otitis (Swimmer's Ear)

    Science.gov (United States)

    ... an otoscope for redness, swelling, and pus. Debris removal, antibiotic ear drops, keeping water out of the ear, and pain relievers are ... cleaning it (using cotton-tipped swabs) or getting water or irritants, such as hair spray or hair dye, in the canal often leads to external otitis. ...

  17. Cochlear implant tailored imaging protocol: What clinicians need to know

    Directory of Open Access Journals (Sweden)

    Tougan Taha

    2015-03-01

    Clinical relevance/application: SNHL is a malfunction of the inner ear, vestibulocochlear nerve or central auditory pathway. Imaging helps to establish treatment regimens that improve auditory function.

  18. Deafness: Cross-modal plasticity and cochlear implants

    Science.gov (United States)

    Lee, Dong Soo; Lee, Jae Sung; Oh, Seung Ha; Kim, Seok-Ki; Kim, Jeung-Whoon; Chung, June-Key; Lee, Myung Chul; Kim, Chong Sun

    2001-01-01

    Hearing in profoundly deaf people can be helped by inserting an implant into the inner ear to stimulate the cochlear nerve. This also boosts the low metabolic activity of the auditory cortex, the region of the brain normally used for hearing. Other sensory modalities, such as sign language, can also activate the auditory cortex, a phenomenon known as cross-modal plasticity. Here we show that when metabolism in the auditory cortex of prelingually deaf children (whose hearing was lost before they learned to talk) has been restored by cross-modal plasticity, the auditory cortex can no longer respond to signals from a cochlear implant installed afterwards. Neural substrates in the auditory cortex might therefore be routed permanently to other cognitive processes in prelingually deaf patients.

  19. "Swimmer's Ear" (Otitis Externa) Prevention

    Science.gov (United States)

    ... drops. Is there a difference between a childhood middle ear infection and swimmer's ear? Yes. Swimmer’s ear ... WASH-related Emergencies & Outbreaks Water, Sanitation, & Environmentally-related Hygiene Get Email Updates To receive email updates about ...

  20. UK and Ireland experience of cochlear implants in children with Down syndrome.

    Science.gov (United States)

    Hans, P S; England, R; Prowse, S; Young, E; Sheehan, P Z

    2010-03-01

    Down Syndrome (DS) is associated with a high incidence of hearing loss. The majority of hearing loss is conductive, but between 4 and 20% is sensorineural, which in the main is mild or moderate and is managed with conventional behind-the-ear hearing aids. Cochlear implantation is an elective invasive procedure, performed to provide some form of hearing rehabilitation in individuals with severe to profound sensorineural hearing loss, and initially candidacy criteria were strict--excluding patients with additional disabilities. With good results and expanding experience, more candidates with additional disabilities are now being implanted. A survey of UK and Ireland Cochlear Implant Programmes sought to identify the number of individuals with DS who have been implanted with a cochlear implant (CI) and to provide relevant information on outcomes of implantation in these individuals. E-mail survey of all programmes within the British Cochlear Implant Group (BCIG). Postal questionnaire to programmes identified to have implanted a child with Down Syndrome, with data collection on pre-operative assessment, surgical and post-operative outcomes. Case series review. Three of 23 BCIG programmes have implanted a child with Down Syndrome. Four children have received implants. No intraoperative or post-operative surgical complications were encountered. All children had middle ear disease, but no problems with implantation were associated with their middle ear condition. All children remain implant users, 12 months to 4 years post-implantation. Cochlear implantation is an option for a child with Down Syndrome and associated severe to profound sensorineural hearing loss. Clinicians caring for these children and their families should consider referral for assessment by a Cochlear Implant Programme. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

  1. Prenatal and postnatal development of the mammalian ear.

    Science.gov (United States)

    Powles-Glover, Nicola; Maconochie, Mark

    2018-02-15

    The ear can be subdivided into three distinct parts, each with significantly distinct structural and functional differences, the outer, middle, and inner ear, the latter housing the specialized sensory hair cells that act as transducers. There are numerous manuscripts documenting the anatomical development of the inner, middle, and outer ear in humans, rodents, chick, and zebrafish, dating back to the early 20th Century, and these developmental processes of these components are further compared in a number of review articles (Anthwal & Thompson, ; Basch, Brown, Jen, & Groves, ; Sai & Ladher, ). This article presents a review of both pre- and postnatal development of the inner ear, discusses recent molecular genetic advances toward our understanding of hair cells responsible for the sensory functions of the inner ear. Finally, a survey of comparative ear biology is used to pull together our understanding of the species differences, similarities, and key time points of definitive organ development of the ear. © 2017 Wiley Periodicals, Inc.

  2. Cochlear compression estimates from measurements of distortion-product otoacoustic emissions.

    Science.gov (United States)

    Neely, Stephen T; Gorga, Michael P; Dorn, Patricia A

    2003-09-01

    Evidence of the compressive growth of basilar-membrane displacement can be seen in distortion-product otoacoustic emission (DPOAE) levels measured as a function of stimulus level. When the levels of the two stimulus tones (f1 and f2) are related by the formula L1 = 39 dB + 0.4 x L2 [Kummer et al., J. Acoust. Soc. Am. 103, 3431-3444 (1998)] the shape of the function relating DPOAE level to L2 is similar (up to an L2 of 70 dB SPL) to the classic Fletcher and Munson [J. Acoust. Soc. Am. 9, 1-10 (1933)] loudness function when plotted on a logarithmic scale. Explicit estimates of compression have been derived based on recent DPOAE measurements from the laboratory. If DPOAE growth rate is defined as the slope of the DPOAE I/O function (in dB/dB), then a cogent definition of compression is the reciprocal of the growth rate. In humans with normal hearing, compression varies from about 1 at threshold to about 4 at 70 dB SPL. With hearing loss, compression is still about 1 at threshold, but grows more slowly above threshold. Median DPOAE I/O data from ears with normal hearing, mild loss, and moderate loss are each well fit by log functions. When the I/O function is logarithmic, then the corresponding compression is a linear function of stimulus level. Evidence of cochlear compression also exists in DPOAE suppression tuning curves, which indicate the level of a third stimulus tone (f3) that reduces DPOAE level by 3 dB. All three stimulus tones generate compressive growth within the cochlea; however, only the relative compression (RC) of the primary and suppressor responses is observable in DPOAE suppression data. An RC value of 1 indicates that the cochlear responses to the primary and suppressor components grow at the same rate. In normal ears, RC rises to 4, when f3 is an octave below f2. The similarities between DPOAE and loudness compression estimates suggest the possibility of predicting loudness growth from DPOAEs; however, intersubject variability makes such

  3. Cochlear Implants (For Parents)

    Science.gov (United States)

    ... the programming process, the user attends speech and language therapy sessions to help identify and interpret the new ... Kids Teens Hearing Evaluation in Children Ears Speech-Language Therapy Auditory Processing Disorder Delayed Speech or Language Development ...

  4. Complications Requiring Cochlear Reimplantation

    Directory of Open Access Journals (Sweden)

    Hajar Bahrani fard

    2011-01-01

    Full Text Available Introduction: Otalgia is one of the complaints which may occur at any age. The etiology of the pain may be in the ear, structures around the ear or other head and neck structures. This is caused by the complex nervous connections in the head and neck areas, the ear, the pharynx and the nose. Since understanding the etiologies of referred otalgia can help in the assessment and treatment of the disease, this research was conducted to identify the etiologies of referred otalgia in patients visiting the ENT Clinic in Gorgan, Iran.   Materials and Methods: This prospective research was conducted on patients who visited the ENT Clinic with an earache, but in initial assessments the ear was normal. Patients’ data consisting of sex, age, complaint, the inflicted side, physical findings in the ear, the nose, the throat and head and neck were recorded in a questionnaire. These data were then analyzed with SPSS software.   Results: Of 770 patients with otalgia, 94 patients (12.2% had referred otalgia. Of these patients 27.7% were men and 72.3% were women. The most common etiology of referred otalgia was dental problems (62.8%, and one patient who was being treated for pharyngitis had carcinoma of the base of the tongue. In 47.8% of cases the pain was in the left ear, in 43.4% in the right ear, and in 8.7% it was bilateral.   Conclusion:  In view of the fact that a significant proportion of the patients who complained of otalgia had no pathologies in the ear, thorough physical examination in adjacent structures especially teeth should be performed and malignancies should be considered as a possible etiology of otalgia.

  5. Ear Problems in Swimmers

    Directory of Open Access Journals (Sweden)

    Mao-Che Wang

    2005-08-01

    Full Text Available Acute diffuse otitis externa (swimmer's ear, otomycosis, exostoses, traumatic eardrum perforation, middle ear infection, and barotraumas of the inner ear are common problems in swimmers and people engaged in aqua activities. The most common ear problem in swimmers is acute diffuse otitis externa, with Pseudomonas aeruginosa being the most common pathogen. The symptoms are itching, otalgia, otorrhea, and conductive hearing loss. The treatment includes frequent cleansing of the ear canal, pain control, oral or topical medications, acidification of the ear canal, and control of predisposing factors. Swimming in polluted waters and ear-canal cleaning with cotton-tip applicators should be avoided. Exostoses are usually seen in people who swim in cold water and present with symptoms of accumulated debris, otorrhea and conductive hearing loss. The treatment for exostoses is transmeatal surgical removal of the tumors. Traumatic eardrum perforations may occur during water skiing or scuba diving and present with symptoms of hearing loss, otalgia, otorrhea, tinnitus and vertigo. Tympanoplasty might be needed if the perforations do not heal spontaneously. Patients with chronic otitis media with active drainage should avoid swimming, while patients who have undergone mastoidectomy and who have no cavity problems may swim. For children with ventilation tubes, surface swimming is safe in a clean, chlorinated swimming pool. Sudden sensorineural hearing loss and some degree of vertigo may occur after diving because of rupture of the round or oval window membrane.

  6. Commissioning of n_TOF EAR2

    CERN Multimedia

    The construction of the second beam line and experiment area (EAR2) of the n_TOF facility is currently ongoing and scheduled to be completed by July 2014. An extensive series of measurements is planned in order to determine the beam characteristics like the neutron flux, the spatial beam profile and the resolution function, as well as the response of several detectors considered for use in future measurements at EAR2. A rigorous study of backgrounds will be undertaken in various conditions.

  7. Use of CT in the evaluation of cochlear otosclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Mafee, M.F.; Valvassori, G.E.; Deitch, R.L.; Norouzi, P.; Henrikson, G.C.; Capek, V.; Applebaum, E.L.

    1985-09-01

    Otosclerosis (otospongiosis) occurs when the hard endochondral bone of the otic capsule is replaced by spongy vascular foci of haversian bone. Using computed tomography (CT), the authors studied the ears of 32 selected patients with mixed or sensorineural hearing loss; 24 were suspected of having otosclerosis. CT proved valuable in detecting cochlear otosclerosis, foci of demineralization, and changes in bony texture and enables the easy recognition of subtle radiographic findings. This paper also reports the CT findings of temporal bones in osteogenesis imperfecta and Paget disease.

  8. Cochlear otosclerosis (otospongiosis): CT analysis with audiometric correlation

    Energy Technology Data Exchange (ETDEWEB)

    Swartz, J.D.; Mandell, D.W.; Berman, S.E.; Wolfson, R.J.; Marlowe, F.I.; Popky, G.L.

    1985-04-01

    Ninety patients who had suspected or confirmed fenestral or cochlear otosclerosis underwent CT examination. Foci of demineralization in the otic capsule were discovered in 20 ears (12 patients). Audiometric studies of the 12 patients revealed sensorineural hearing loss (SNHL) with distinct correlation of CT findings with progressivity and with involvement of the frequency level subtended by the specific area of the cochlea involved. Foci of abnormal increased density, presumably representing the healed phase of this disorder, were found less frequently than expected. There was a predilection for the basilar turn. All patients had static SNHL in the higher frequencies. The healed phase of this disorder is probably not consistently diagnosable with CT.

  9. Efter cochlear implant

    DEFF Research Database (Denmark)

    Højen, Anders

    2007-01-01

      Dit barn har netop fået et cochlear implant. Hvad nu? Skal barnet fokusere udelukkende på at lære talt sprog, eller skal det også lære/fortsætte med tegnsprog eller støttetegn? Det er et vanskeligt spørgsmål, og før valget foretages, er det vigtigt at vurdere hvilke konsekvenser valget har, dels...... for den sproglige udvikling isoleret set, og dels for barnets udvikling ud fra en helhedsbetragtning. Dette indlæg fokuserer på, hvilke forventninger man kan have til cochlear implant-brugeres sproglige udvikling med talt sprog alene, hhv. med to sprog (tale og tegn). Disse forventninger er baseret på...

  10. Efter cochlear implant

    DEFF Research Database (Denmark)

    Højen, Anders

    Dit barn har netop fået et cochlear implant. Hvad nu? Skal barnet fokusere udelukkende på at lære talt sprog, eller skal det også lære/fortsætte med tegnsprog eller støttetegn? Det er et vanskeligt spørgsmål, og før valget foretages, er det vigtigt at vurdere hvilke konsekvenser valget har, dels...... for den sproglige udvikling isoleret set, og dels for barnets udvikling ud fra en helhedsbetragtning. Dette indlæg fokuserer på, hvilke forventninger man kan have til cochlear implant-brugeres sproglige udvikling med talt sprog alene, hhv. med to sprog (tale og tegn). Disse forventninger er baseret på...

  11. From hearing with a cochlear implant and a contralateral hearing aid (CI/HA) to hearing with two cochlear implants (CI/CI): a within-subject design comparison.

    Science.gov (United States)

    Luntz, Michal; Egra-Dagan, Dana; Attias, Joseph; Yehudai, Noam; Most, Tova; Shpak, Talma

    2014-12-01

    To compare within-subject bilateral-binaural and bimodal complementary abilities between bimodal (cochlear implant and hearing aid; CI/HA) and bilateral CI hearing (CI/CI), thereby enabling better-informed counseling of experienced CI/HA users contemplating contralateral implantation. Comparative within-subject case review. Outpatient hearing clinic. Ten experienced adult CI/HA users with severe-to-profound hearing loss in the HA ear, who converted to CI/CI between 2 and 11 years after initial implantation. Task-specific testing of bilateral-binaural hearing (sound lateralization, binaural summation/redundancy/unmasking, head-shadow effect), bimodal complementary benefit (contribution of low-frequency information), and a self-report Speech, Spatial, and Qualities of Hearing (SSQ) questionnaire, all before and 1 year after contralateral cochlear implantation. Test result differences between CI/HA and CI/CI conditions. CI/CI hearing was better than CI/HA for speech lateralization and for perception of semantically unpredictable sentences in speech noise with speech at 0 degrees and noise at +90 degrees azimuth on the old CI side. CI/HA was better than CI/CI only for differences between perception of natural prosody speech and of speech with flattened fundamental frequency (F0) contour with speech and noise in front (at 0 degrees azimuth). Total scores on the SSQ questionnaire were higher in CI/CI than in CI/HA users. Counseling regarding contralateral implantation for CI/HA users with severe-to-profound hearing loss in the HA ear, though generally positive, should consider individual functional needs, and cover expectations about the expected trade-off between gaining improved understanding and speech lateralization in challenging listening conditions and losing some low-frequency cues still available with CI/HA hearing.

  12. Music enjoyment with cochlear implantation.

    Science.gov (United States)

    Prevoteau, Charlotte; Chen, Stephanie Y; Lalwani, Anil K

    2018-03-05

    Since the advent of cochlear implant (CI) surgery in the 1960s, there have been remarkable technological and surgical advances enabling excellent speech perception in quiet with many CI users able to use the telephone. However, many CI users struggle with music perception, particularly with the pitch-based and melodic elements of music. Yet remarkably, despite poor music perception, many CI users enjoy listening to music based on self-report questionnaires, and prospective studies have suggested a disassociation between music perception and enjoyment. Music enjoyment is arguably a more functional measure of one's listening experience, and thus enhancing one's listening experience is a worthy goal. Recent studies have shown that re-engineering music to reduce its complexity may enhance enjoyment in CI users and also delineate differences in musical preferences from normal hearing listeners. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Blood circulation of the inner ear under the influence of medications. Radiotracer experiments using guinea pig cochlea

    International Nuclear Information System (INIS)

    Neumeier, A.

    1987-01-01

    The dependence of the blood circulation in the inner ear on various medications is discussed. By means of a radiotracer clearance technique the cochlear clearance curves for the guinea pig cochlea after the administration of various circulation stimulants were determined. (MBC) [de

  14. 78 FR 63225 - Ear, Nose and Throat Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Science.gov (United States)

    2013-10-23

    ... HUMAN SERVICES Food and Drug Administration Ear, Nose and Throat Devices Panel of the Medical Devices... Federal Register about last minute modifications that impact a previously announced advisory committee... for the Nucleus Hybrid TM L24 Implant System sponsored by Cochlear Americas. The proposed Indications...

  15. Ear Infections - Multiple Languages

    Science.gov (United States)

    ... Ear Infection in Children - 简体中文 (Chinese, Simplified (Mandarin dialect)) Bilingual PDF Health Information Translations Chinese, Traditional (Cantonese dialect) (繁體中文) Expand Section Middle ...

  16. Ear tube insertion

    Science.gov (United States)

    ... mastoiditis) or the brain, or that damages nearby nerves Injury to the ear after sudden changes in ... does not heal after the tube falls out. Most of the time, these problems DO NOT last long. They also ...

  17. Developmental Changes of ENaC Expression and Function in the Inner Ear of Pendrin Knock-Out Mice as a Perspective on the Development of Endolymphatic Hydrops

    Science.gov (United States)

    Kim, Bo Gyung; Kim, Jin Young; Kim, Hee Nam; Bok, Jinwoong; Namkung, Wan

    2014-01-01

    Pendrin mutations cause enlarged vestibular aqueducts and various degrees of sensorineural hearing loss. The selective abolition of pendrin causes dilation of the membranous labyrinth known as endolymphatic hydrops, loss of the endocochlear potential, and consequently loss of hearing function. Because Na+ transport is one of the most important driving forces for fluid transport, the epithelial Na+ channel (ENaC) is believed to play an important role in fluid volume regulation in the inner ear. Therefore, the dysfunction of Na+ transport through ENaC by the acidification of endolymph in Pendred syndrome is one of the potential causes of endolymphatic hydrops. We investigated the changes of ENaC expression and function during the development of the pendrin knock-out mouse. In the cochlea, the expression of β and γENaC was significantly increased at P56 in Pds−/− mice compared with Pds+/+ mice. In the vestibule, the expression of βENaC was significantly increased at P56, and γENaC expression significantly increased from P6 to P56 in Pds−/− mice. The ENaC-dependent trans-epithelial current was not significantly different between Pds+/+ and Pds−/− mice in Reissner’s membrane or the saccular extramacular roof epithelium at P0, but the current was significantly increased in Pds−/− mice at P56 compared with Pds+/+ mice. These findings indicate that the expression and function of ENaC were enhanced in Pds−/− mice after the development of endolymphatic hydrops as a compensatory mechanism. This result provides insight into the role of Na+ transport in the development and regulation of endolymphatic hydrops due to pendrin mutations. PMID:24752462

  18. Developmental changes of ENaC expression and function in the inner ear of pendrin knock-out mice as a perspective on the development of endolymphatic hydrops.

    Directory of Open Access Journals (Sweden)

    Bo Gyung Kim

    Full Text Available Pendrin mutations cause enlarged vestibular aqueducts and various degrees of sensorineural hearing loss. The selective abolition of pendrin causes dilation of the membranous labyrinth known as endolymphatic hydrops, loss of the endocochlear potential, and consequently loss of hearing function. Because Na+ transport is one of the most important driving forces for fluid transport, the epithelial Na+ channel (ENaC is believed to play an important role in fluid volume regulation in the inner ear. Therefore, the dysfunction of Na+ transport through ENaC by the acidification of endolymph in Pendred syndrome is one of the potential causes of endolymphatic hydrops. We investigated the changes of ENaC expression and function during the development of the pendrin knock-out mouse. In the cochlea, the expression of β and γENaC was significantly increased at P56 in Pds-/- mice compared with Pds+/+ mice. In the vestibule, the expression of βENaC was significantly increased at P56, and γENaC expression significantly increased from P6 to P56 in Pds-/- mice. The ENaC-dependent trans-epithelial current was not significantly different between Pds+/+ and Pds-/- mice in Reissner's membrane or the saccular extramacular roof epithelium at P0, but the current was significantly increased in Pds-/- mice at P56 compared with Pds+/+ mice. These findings indicate that the expression and function of ENaC were enhanced in Pds-/- mice after the development of endolymphatic hydrops as a compensatory mechanism. This result provides insight into the role of Na+ transport in the development and regulation of endolymphatic hydrops due to pendrin mutations.

  19. Visualization of normal and abnormal inner ear with volume rendering technique using multislice spiral CT

    International Nuclear Information System (INIS)

    Ma Hui; Han Ping; Liang Bo; Lei Ziqiao; Liu Fang; Tian Zhiliang

    2006-01-01

    Objective: To evaluate the ability of the volume rendering technique to display the normal and abnormal inner ear structures. Methods: Forty normal earand 61 abnormal inner ears (40 congenital inner ear malformations, 7 labyrinthitis ossificans, and 14 inner ear erosion caused by cholesteatomas) were examined with a MSCT scanner. Axial imaging were performed using the following parameters: 120 kV, 100 mAs, 0.75 mm slice thickness, a pitch factor of 1. The axial images of interested ears were reconstructed with 0.1 mm reconstruction increment and a FOV of 50 mm. The 3D reconstructions were done with volume rendering technique on the workstation. Results: In the subjects without ear disorders a high quality 3D visualization of the inner ear could be achieved. In the patients with inner ear' disorders all inner ear malformations could be clearly displayed on 3D images as follows: (1) Michel deformity (one ear): There was complete absence of all cochlear and vestibular structures. (2) common cavity deformity (3 ears): The cochlea and vestibule were represented by a cystic cavity and couldn't be differentiated from each other. (3)incomplete partition type I (3 ears): The cochlea lacked the entire modiolus and cribriform area, resulting in a cystic appearance. (4) incomplete partition type II (Mondini deformity) (5 ears): The cochlea consisted of 1.5 turns, in which the middle and apical turns coalesced to form a cystic apex. (5) vestibular and semicircular canal malformations (14 ears): Cochlea was normal, vestibule dilated, semicircular canals were absent, hypoplastic or enlarged. (6) dilated vestibular aqueduct (14 ears): The vestibular aqueduct was bell-mouthed. In 7 patients with labyrinthifis ossificans, 3D images failed to clearly show the completeinner ears in 4 ears because of too high ossifications in the membranous labyrinth. In the other 3 ears volume rendering could display the thin cochlea basal turn and the intermittent semicircular canals. In the patients

  20. Contribution of Family Environment to Pediatric Cochlear Implant Users' Speech and Language Outcomes: Some Preliminary Findings

    Science.gov (United States)

    Holt, Rachael Frush; Beer, Jessica; Kronenberger, William G.; Pisoni, David B.; Lalonde, Kaylah

    2012-01-01

    Purpose: To evaluate the family environments of children with cochlear implants and to examine relationships between family environment and postimplant language development and executive function. Method: Forty-five families of children with cochlear implants completed a self-report family environment questionnaire (Family Environment Scale-Fourth…

  1. Exploiting decellularized cochleae as scaffolds for inner ear tissue engineering.

    Science.gov (United States)

    Mellott, Adam J; Shinogle, Heather E; Nelson-Brantley, Jennifer G; Detamore, Michael S; Staecker, Hinrich

    2017-02-28

    Use of decellularized tissues has become popular in tissue engineering applications as the natural extracellular matrix can provide necessary physical cues that help induce the restoration and development of functional tissues. In relation to cochlear tissue engineering, the question of whether decellularized cochlear tissue can act as a scaffold and support the incorporation of exogenous cells has not been addressed. Investigators have explored the composition of the cochlear extracellular matrix and developed multiple strategies for decellularizing a variety of different tissues; however, no one has investigated whether decellularized cochlear tissue can support implantation of exogenous cells. As a proof-of-concept study, human Wharton's jelly cells were perfused into decellularized cochleae isolated from C57BL/6 mice to determine if human Wharton's jelly cells could implant into decellularized cochlear tissue. Decellularization was verified through scanning electron microscopy. Cocheae were stained with DAPI and immunostained with Myosin VIIa to identify cells. Perfused cochleae were imaged using confocal microscopy. Features of the organ of Corti were clearly identified in the native cochleae when imaged with scanning electron microscopy and confocal microscopy. Acellular structures were identified in decellularized cochleae; however, no cellular structures or lipid membranes were present within the decellularized cochleae when imaged via scanning electron microscopy. Confocal microscopy revealed positive identification and adherence of cells in decellularized cochleae after perfusion with human Wharton's jelly cells. Some cells positively expressed Myosin VIIa after perfusion. Human Wharton's jelly cells are capable of successfully implanting into decellularized cochlear extracellular matrix. The identification of Myosin VIIa expression in human Wharton's jelly cells after implantation into the decellularized cochlear extracellular matrix suggest that

  2. Drug delivery to the inner ear

    Science.gov (United States)

    Wise, Andrew K.; Gillespie, Lisa N.

    2012-12-01

    Bionic devices electrically activate neural populations to partially restore lost function. Of fundamental importance is the functional integrity of the targeted neurons. However, in many conditions the ongoing pathology can lead to continued neural degeneration and death that may compromise the effectiveness of the device and limit future strategies to improve performance. The use of drugs that can prevent nerve cell degeneration and promote their regeneration may improve clinical outcomes. In this paper we focus on strategies of delivering neuroprotective drugs to the auditory system in a way that is safe and clinically relevant for use in combination with a cochlear implant. The aim of this approach is to prevent neural degeneration and promote nerve regrowth in order to improve outcomes for cochlear implant recipients using techniques that can be translated to the clinic.

  3. Development of a phase-sensitive Fourier domain optical coherence tomography system to measure mouse organ of Corti vibrations in two cochlear turns

    Energy Technology Data Exchange (ETDEWEB)

    Ramamoorthy, Sripriya [Oregon Hearing Research Center, Oregon Health & Science University, Portland, Oregon (United States); Zhang, Yuan; Jacques, Steven [Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon (United States); Petrie, Tracy; Wang, Ruikang [Department of Bioengineering, University of Washington, Seattle, Washington (United States); Nuttall, Alfred L. [Oregon Hearing Research Center, Oregon Health & Science University, Portland, Oregon (United States); Kresge Hearing Research Institute, The University of Michigan, Ann Arbor, Michigan (United States)

    2015-12-31

    In this study, we have developed a phase-sensitive Fourier-domain optical coherence tomography system to simultaneously measure the in vivo inner ear vibrations in the hook area and second turn of the mouse cochlea. This technical development will enable measurement of intra-cochlear distortion products at ideal locations such as the distortion product generation site and reflection site. This information is necessary to un-mix the complex mixture of intra-cochlear waves comprising the DPOAE and thus leads to the non-invasive identification of the local region of cochlear damage.

  4. Mouse middle ear ion homeostasis channels and intercellular junctions.

    Directory of Open Access Journals (Sweden)

    Lisa M Morris

    Full Text Available The middle ear contains homeostatic mechanisms that control the movement of ions and fluids similar to those present in the inner ear, and are altered during inflammation.The normal middle ear cavity is fluid-free and air-filled to allow for effective sound transmission. Within the inner ear, the regulation of fluid and ion movement is essential for normal auditory and vestibular function. The same ion and fluid channels active in the inner ear may have similar roles with fluid regulation in the middle ear.Middle and inner ears from BALB/c mice were processed for immunohistochemistry of 10 specific ion homeostasis factors to determine if similar transport and barrier mechanisms are present in the tympanic cavity. Examination also was made of BALB/c mice middle ears after transtympanic injection with heat-killed Haemophilus influenza to determine if these channels are impacted by inflammation.The most prominent ion channels in the middle ear included aquaporins 1, 4 and 5, claudin 3, ENaC and Na(+,K(+-ATPase. Moderate staining was found for GJB2, KCNJ10 and KCNQ1. The inflamed middle ear epithelium showed increased staining due to expected cellular hypertrophy. Localization of ion channels was preserved within the inflamed middle ear epithelium.The middle ear epithelium is a dynamic environment with intrinsic mechanisms for the control of ion and water transport to keep the middle ear clear of fluids. Compromise of these processes during middle ear disease may underlie the accumulation of effusions and suggests they may be a therapeutic target for effusion control.

  5. Bilateral Sequential Cochlear Implantation in Patients With Enlarged Vestibular Aqueduct (EVA) Syndrome.

    Science.gov (United States)

    Manzoor, Nauman F; Wick, Cameron C; Wahba, Marian; Gupta, Amit; Piper, Robin; Murray, Gail S; Otteson, Todd; Megerian, Cliff A; Semaan, Maroun T

    2016-02-01

    To analyze audiometric outcomes after bilateral cochlear implantation in patients with isolated enlarged vestibular aqueduct (EVA) syndrome and associated incomplete partition (IP) malformations. Secondary objective was to analyze rate of cerebrospinal fluid (CSF) gusher in patients with IP-EVA spectrum deformities and compare this with the existing literature. Retrospective chart review. Thirty-two patients with EVA syndrome who received unilateral or bilateral cochlear implants between June 1999 and January 2014 were identified in the University Hospitals Case Medical Center cochlear implant database. Isolated EVA (IEVA) and Incomplete Partition Type II (IP-II) malformations were identified by reviewing high-resolution computed tomography (HRCT) imaging. Demographic information, age at implantation, surgical details, postimplantation audiometric data including speech reception thresholds (SRT), word, and sentence scores were reviewed and analyzed. Intra- and postoperative complications were analyzed as well and compared with the literature. Seventeen patients (32 implanted ears) had pediatric cochlear implantation for EVA-associated hearing loss. Data from 16 controls (32 implanted ears) were used to compare audiometric and speech outcomes of EVA cohort. Mean age at implantation was 6.8 years for EVA cohort and 6.0 years for controls. There was no statistically significant difference in long-term postoperative SRT, monaurally aided word scores, and binaurally tested word scores between pediatric EVA group and controls. The EVA patients had a long-term mean sentence score of 85.92%. A subset of EVA patients implanted at mean age of 3.18 years (n = 15 ears) had similar audiometric outcomes to another control group with Connexin 26 mutations (n = 20 ears) implanted at a similar age. Further subset analysis revealed no significant differences in age at implantation, SRT, and word scores in patients with IEVA and IP-II malformation. There was no significant

  6. Audiological findings after multichannel cochlear implantation in patients with Mondini dysplasia.

    Science.gov (United States)

    Munro, K J; George, C R; Haacke, N P

    1996-12-01

    Mondini dysplasia is a congenital malformation of the inner ear. To date, five individuals with this malformation have received cochlear implants at the South of England Cochlear Implant Centre. The aim of this study was to review the audiological findings of these individuals after implantation. The soundfield thresholds after implantation are in the region of 30-40 dB (A). The results of suprathreshold speech recognition tasks show substantial variability in performance but this is no greater than that obtained from implant users with no malformation. All individuals were able to detect and recognize a variety of environmental sounds that would previously have been inaudible. These findings, along with the reported improvement in quality of life, mean that Mondini dysplasia is not a contra-indication for multichannel cochlear implantation. This information will be useful to other centres when considering implantation in similar patients.

  7. Congenital cholesteatoma of the middle ear - uncommon clinical presentation

    Directory of Open Access Journals (Sweden)

    Bukurov Bojana

    2014-01-01

    Full Text Available Introduction. Congenital cholesteatoma of the middle ear is un uncommon and yet not well-defined disease. Only few cases of cholesteatoma in the fossa ovalis with unusual clinical presentation have been reported in medical literature. Case report. We reported a 16-year-old girl with congenital cholesteatoma in the fossa ovalis with minimal clinical presentation. A small mass was found occluding the fossa ovalis and mimicking otosclerotic process within tympanic cavity. The operation started as stapedotomy, and when the process was confirmed it converted to mastoidectomy via the retroauricular approach. Conclusion. The diagnosis of congenital cholesteatoma in children should always be considered, even if the clinical symptoms imitate other ear disorders, in our case otosclerosis. [Projekat Ministarstva nauke Republike Srbije, br. 179055: Cochlear implantation impact on education of deaf and hearing-impaired

  8. A study on the cochlear view in multichannel cochlear implantees

    Energy Technology Data Exchange (ETDEWEB)

    Kweon, Dae Cheol; Kim, Jeong Hee; Kim, Seong Lyong; Kim, Hae Seong; Lee, Yong Woo [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

    1999-04-01

    Cochlear implant poses a contraindication to the magnetic resonance imaging(MRI) process, because MRI generates artifacts, inducing an electrical current and causing device magnetization. CT is relatively expensive and the metal electrodes scatter the image. Post-implantation radiological studies using anterior-posterior transorbital, submental-vertex and lateral views, the intracochlear electrodes are not well displayed. Therefore, the authors developed a special view, which we call the cochlear view. The patient is sitting in front of a vertical device. Then the midsagittal plane is adjusted to form an angle of 15 .deg. , 30 .deg. , and 45 .deg. with the film. The flexion of the neck is adjusted to make the infraorbitomeatal line(IOML) is parallel with the transverse axis of the film. The central ray is directed to exit from the skull at point which is 3.0 cm anterior and 2.0 cm superior to the EAM(external auditory meatus). Results have shown that single radiography of the cochlear view provides sufficient information to demonstrate the position of the electrodes array and the depth of insertion in cochlear. Radiography of the cochlear view in angle of 45 .deg. is an excellent image. The cochlear view gives the greatest amount of medical information with the least radiation and lowest medical cost. It can be widely used in all cochlear implant clinics.

  9. Characterization of Cochlear, Vestibular and Cochlear-Vestibular Electrically Evoked Compound Action Potentials in Patients with a Vestibulo-Cochlear Implant

    Directory of Open Access Journals (Sweden)

    T. A. K. Nguyen

    2017-11-01

    Full Text Available The peripheral vestibular system is critical for the execution of activities of daily life as it provides movement and orientation information to motor and sensory systems. Patients with bilateral vestibular hypofunction experience a significant decrease in quality of life and have currently no viable treatment option. Vestibular implants could eventually restore vestibular function. Most vestibular implant prototypes to date are modified cochlear implants to fast-track development. These use various objective measurements, such as the electrically evoked compound action potential (eCAP, to supplement behavioral information. We investigated whether eCAPs could be recorded in patients with a vestibulo-cochlear implant. Specifically, eCAPs were successfully recorded for cochlear and vestibular setups, as well as for mixed cochlear-vestibular setups. Similarities and slight differences were found for the recordings of the three setups. These findings demonstrated the feasibility of eCAP recording with a vestibulo-cochlear implant. They could be used in the short term to reduce current spread and avoid activation of non-targeted neurons. More research is warranted to better understand the neural origin of vestibular eCAPs and to utilize them for clinical applications.

  10. The cochlear nuclei of snakes.

    Science.gov (United States)

    Miller, M R

    1980-08-15

    The cochlear nuclei of three burrowing snakes (Xenopeltis unicolor, Cylindrophis rufus, and Eryx johni) and three non-burrowing snakes (Epicrates cenchris, Natrix sipedon, and Pituophis catenifer) were studied. The posterior branch of the statoacoustic nerve and its posterior ganglion were destroyed and the degenerated nerve fibers and terminals traced to primary cochlear nuclei in 13 specimens of Pituophis catenifer. All these snake species possess three primary and one secondary cochlear nuclei. The primary cochlear nuclei consist of a small nucleus angularis located at the cerebello-medullary junction and a fairly large nucleus magnocellularis forming a dorsal cap over the cephalic end of the alar eminence. Nucleus magnocellularis may be subdivided into a medially placed group of rounder cells, nucleus magnocellularis medialis, and a laterally placed group of more ovate and paler-staining cells, nucleus magnocellularis lateralis. A small but well-defined secondary nucleus which showed no degenerated nerve terminals after nerve root section, nucleus laminaris, underlies the cephalic part of both nucleus magnocellularis medialis and nucleus magnocellularis lateralis. Larger and better-developed cochlear nuclei were found in burrowing species than in non-burrowing species of snakes. Of the three burrowing species studied, Xenopeltis showed the greatest development of cochlear nuclei; Eryx cochlear nuclei were not quite as large but were better differentiated than in Xenopeltis; and Cylindrophis cochlear nuclei were fairly large but not as well developed nor as well differentiated as in either Xenopeltis or Eryx. The cochlear nuclei of the three non-burrowing snakes, Epicrates, Natrix, and Pituophis, were not as large nor as well developed as those of the burrowing snakes. There is some, but not complete, correlation between cochlear development and papilla basilaris length and number of hair cells. Thus, Xenopeltis and Eryx, with well-developed cochlear nuclei

  11. BAAV Mediated GJB2 Gene Transfer Restores Gap Junction Coupling in Cochlear Organotypic Cultures from Deaf Cx26Sox10Cre Mice

    Science.gov (United States)

    Crispino, Giulia; Di Pasquale, Giovanni; Scimemi, Pietro; Rodriguez, Laura; Galindo Ramirez, Fabian; De Siati, Romolo Daniele; Santarelli, Rosa Maria; Arslan, Edoardo; Bortolozzi, Mario; Chiorini, John A.; Mammano, Fabio

    2011-01-01

    The deafness locus DFNB1 contains GJB2, the gene encoding connexin26 and GJB6, encoding connexin30, which appear to be coordinately regulated in the inner ear. In this work, we investigated the expression and function of connexin26 and connexin30 from postnatal day 5 to adult age in double transgenic Cx26Sox10Cre mice, which we obtained by crossing connexin26 floxed mice with a deleter Sox10–Cre line. Cx26Sox10Cre mice presented with complete connexin26 ablation in the epithelial gap junction network of the cochlea, whereas connexin30 expression was developmentally delayed; immunolabeling patterns for both connexins were normal in the cochlear lateral wall. In vivo electrophysiological measurements in Cx26Sox10Cre mice revealed profound hearing loss accompanied by reduction of endocochlear potential, and functional experiments performed in postnatal cochlear organotypic cultures showed impaired gap junction coupling. Transduction of these cultures with a bovine adeno associated virus vector restored connexin26 protein expression and rescued gap junction coupling. These results suggest that restoration of normal connexin levels by gene delivery via recombinant adeno associated virus could be a way to rescue hearing function in DFNB1 mouse models and, in future, lead to the development of therapeutic interventions in humans. PMID:21876744

  12. BAAV mediated GJB2 gene transfer restores gap junction coupling in cochlear organotypic cultures from deaf Cx26Sox10Cre mice.

    Directory of Open Access Journals (Sweden)

    Giulia Crispino

    Full Text Available The deafness locus DFNB1 contains GJB2, the gene encoding connexin26 and GJB6, encoding connexin30, which appear to be coordinately regulated in the inner ear. In this work, we investigated the expression and function of connexin26 and connexin30 from postnatal day 5 to adult age in double transgenic Cx26(Sox10Cre mice, which we obtained by crossing connexin26 floxed mice with a deleter Sox10-Cre line. Cx26(Sox10Cre mice presented with complete connexin26 ablation in the epithelial gap junction network of the cochlea, whereas connexin30 expression was developmentally delayed; immunolabeling patterns for both connexins were normal in the cochlear lateral wall. In vivo electrophysiological measurements in Cx26(Sox10Cre mice revealed profound hearing loss accompanied by reduction of endocochlear potential, and functional experiments performed in postnatal cochlear organotypic cultures showed impaired gap junction coupling. Transduction of these cultures with a bovine adeno associated virus vector restored connexin26 protein expression and rescued gap junction coupling. These results suggest that restoration of normal connexin levels by gene delivery via recombinant adeno associated virus could be a way to rescue hearing function in DFNB1 mouse models and, in future, lead to the development of therapeutic interventions in humans.

  13. A novel inner ear monitoring system for evaluating ototoxicity of gentamicin eardrops in guinea pigs.

    Science.gov (United States)

    Yang, Ting-Hua; Liu, Shing-Hwa; Young, Yi-Ho

    2010-06-01

    Although most studies have identified damage in the cochlea and semicircular canals as the primary sites of aminoglycoside toxicity, little attention has been devoted to the toxic effects on the otolithic organs. This study aimed to assess the toxic effect of gentamicin eardrops on the inner ear end organs via a novel inner ear monitoring system combined with morphological examination. Prospective study. Guinea pigs were treated with 50 microL saline (n = 10) and 50 microL gentamicin (40 mg/mL; n = 10) on the right and left round window membranes, respectively. An inner ear monitoring system, including auditory brainstem response (ABR), caloric, ocular vestibular-evoked myogenic potential (oVEMP), and cervical VEMP (cVEMP) tests, was used to assess ototoxicity in guinea pigs at 2 weeks after treatment. The animals were then sacrificed for morphological study via confocal microscopy. Normal results in ABR, caloric, cVEMP, and oVEMP tests were shown in all saline-treated ears, whereas elevated ABR threshold and absent responses in caloric, oVEMP, and cVEMP tests were noted in all gentamicin-treated ears. The cochlear and vestibular explants harvested from the gentamicin-treated ears revealed substantial loss of hair cells. The inner ear monitoring system, including ABR, caloric, oVEMP, and cVEMP tests, might help to evaluate toxicity information of the topical eardrops or agents on the inner ear end organs, including cochlea, semicircular canals, utricle, and saccule.

  14. [SOX10 mutation is relevant to inner ear malformation in patients with Waardenburg syndrome].

    Science.gov (United States)

    Xu, G Y; Hao, Q Q; Zhong, L L; Ren, W; Yan, Y; Liu, R Y; Li, J N; Guo, W W; Zhao, H; Yang, S M

    2016-11-07

    Objective: To determine the relevance between the SOX 10 mutation and Waardenburg syndrome (WS) accompanied with inner ear abnormality by analyzing the inner ear imaging results and molecular and genetic results of the WS patients with the SOX 10 mutation. Methods: This study included 36 WS in patients during 2001 and 2015 in the department of otorhinolaryngology head and neck surgery, Chinese Peoples's Liberation Army General Hospital. The condition of the inner ear of each patient was assessed by analyzing HRCT scans of the temporal bone and MRI scans of the brain and internal auditory canal. Meanwhile, the possible pathogenic genes of WS, including SOX10, MITF , and PAX 3, were also screened. Patients were divided into two groups according to SOX 10 mutation.The Fisher accuracy test was used to determine statistical difference of inner ear deformation incidence between the two groups. Results: Among all 36 patients, 12 were found to have inner ear abnormality. Most abnormalities were posterior semicircular canal deformations, some accompanied with cochlear deformation and an enlarged vestibule. Among all patients, 9 patients were SOX 10 heterozygous mutation carriers, among which six showed bilateral inner ear abnormality. Fisher accuracy test results suggested a significant correlation between the SOX 10 mutation and inner ear abnormality in WS patients ( P =0.036). Conclusion: This study found that WS patients with the SOX 10 mutation are more likely to have deformed inner ears when compared to WS patients without the SOX 10 mutation.

  15. Mouse Panx1 Is Dispensable for Hearing Acquisition and Auditory Function.

    Science.gov (United States)

    Zorzi, Veronica; Paciello, Fabiola; Ziraldo, Gaia; Peres, Chiara; Mazzarda, Flavia; Nardin, Chiara; Pasquini, Miriam; Chiani, Francesco; Raspa, Marcello; Scavizzi, Ferdinando; Carrer, Andrea; Crispino, Giulia; Ciubotaru, Catalin D; Monyer, Hannah; Fetoni, Anna R; M Salvatore, Anna; Mammano, Fabio

    2017-01-01

    Panx1 forms plasma membrane channels in brain and several other organs, including the inner ear. Biophysical properties, activation mechanisms and modulators of Panx1 channels have been characterized in detail, however the impact of Panx1 on auditory function is unclear due to conflicts in published results. To address this issue, hearing performance and cochlear function of the Panx1 -/- mouse strain, the first with a reported global ablation of Panx1 , were scrutinized. Male and female homozygous ( Panx1 -/-), hemizygous ( Panx1 +/-) and their wild type (WT) siblings ( Panx1 +/+) were used for this study. Successful ablation of Panx1 was confirmed by RT-PCR and Western immunoblotting in the cochlea and brain of Panx1 -/- mice. Furthermore, a previously validated Panx1-selective antibody revealed strong immunoreactivity in WT but not in Panx1 -/- cochleae. Hearing sensitivity, outer hair cell-based "cochlear amplifier" and cochlear nerve function, analyzed by auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) recordings, were normal in Panx1 +/- and Panx1 -/- mice. In addition, we determined that global deletion of Panx1 impacts neither on connexin expression, nor on gap-junction coupling in the developing organ of Corti. Finally, spontaneous intercellular Ca 2+ signal (ICS) activity in organotypic cochlear cultures, which is key to postnatal development of the organ of Corti and essential for hearing acquisition, was not affected by Panx1 ablation. Therefore, our results provide strong evidence that, in mice, Panx1 is dispensable for hearing acquisition and auditory function.

  16. Semicircular canal morphogenesis in the zebrafish inner ear requires the function of gpr126 (lauscher), an adhesion class G protein-coupled receptor gene

    Science.gov (United States)

    Geng, Fan-Suo; Abbas, Leila; Baxendale, Sarah; Holdsworth, Celia J.; Swanson, A. George; Slanchev, Krasimir; Hammerschmidt, Matthias; Topczewski, Jacek; Whitfield, Tanya T.

    2013-01-01

    Morphogenesis of the semicircular canal ducts in the vertebrate inner ear is a dramatic example of epithelial remodelling in the embryo, and failure of normal canal development results in vestibular dysfunction. In zebrafish and Xenopus, semicircular canal ducts develop when projections of epithelium, driven by extracellular matrix production, push into the otic vesicle and fuse to form pillars. We show that in the zebrafish, extracellular matrix gene expression is high during projection outgrowth and then rapidly downregulated after fusion. Enzymatic disruption of hyaluronan in the projections leads to their collapse and a failure to form pillars: as a result, the ears swell. We have cloned a zebrafish mutant, lauscher (lau), identified by its swollen ear phenotype. The primary defect in the ear is abnormal projection outgrowth and a failure of fusion to form the semicircular canal pillars. Otic expression of extracellular matrix components is highly disrupted: several genes fail to become downregulated and remain expressed at abnormally high levels into late larval stages. The lau mutations disrupt gpr126, an adhesion class G protein-coupled receptor gene. Expression of gpr126 is similar to that of sox10, an ear and neural crest marker, and is partially dependent on sox10 activity. Fusion of canal projections and downregulation of otic versican expression in a hypomorphic lau allele can be restored by cAMP agonists. We propose that Gpr126 acts through a cAMP-mediated pathway to control the outgrowth and adhesion of canal projections in the zebrafish ear via the regulation of extracellular matrix gene expression. PMID:24067352

  17. The hearing benefit of cochlear implantation for individuals with unilateral hearing loss, but no tinnitus.

    Science.gov (United States)

    Skarzynski, Henryk; Lorens, Artur; Kruszynska, Marika; Obrycka, Anita; Pastuszak, Dorota; Skarzynski, Piotr Henryk

    2017-07-01

    Cochlear implants improve the hearing abilities of individuals with unilateral hearing loss and no tinnitus. The benefit is no different from that seen in patients with unilateral hearing loss and incapacitating tinnitus. To evaluate hearing outcomes after cochlear implantation in individuals with unilateral hearing loss and no tinnitus and compare them to those obtained in a similar group who had incapacitating tinnitus. Six cases who did not experience tinnitus before operation and 15 subjects with pre-operative tinnitus were evaluated with a structured interview, a monosyllabic word test under difficult listening situations, a sound localization test, and an APHAB (abbreviated profile of hearing aid benefit) questionnaire. All subjects used their cochlear implant more than 8 hours a day, 7 days a week. In 'no tinnitus' patients, mean benefit of cochlear implantation was 19% for quiet speech, 15% for speech in noise (with the same signal-to-noise ratio in the implanted and non-implanted ear), and 16% for a more favourable signal-to-noise ratio at the implanted ear. Sound localization error improved by an average of 19°. The global score of APHAB improved by 16%. The benefits across all evaluations did not differ significantly between the 'no tinnitus' and 'tinnitus' groups.

  18. Experience with cochlear implants in Greenlanders with profound hearing loss living in Greenland

    DEFF Research Database (Denmark)

    Homøe, Preben; Andersen, Ture; Grøntved, Aksel

    2013-01-01

    Cochlear implant (CI) treatment was introduced to the world in the 1980s and has become a routine treatment for congenital or acquired severe-to-profound hearing loss. CI treatment requires access to a highly skilled team of ear, nose and throat specialists, audiologists and speech......-language pathologists for evaluation, surgery and rehabilitation. In particular, children treated with CI are in need of long-term post-operative auditory training and other follow-up support....

  19. Paediatric cochlear implantation

    African Journals Online (AJOL)

    Chantel

    sensations. The electrodes stimu- late the nerve fibres via a con- trolled electrical current which is recognised by the brain as sound. Electrical stimulation of the .... tion, and middle ear status. Magnetic resonance imaging. (MRI) is particularly useful for. Age. Hearing level. Speech. Other. (years). (dB) perception score. 1-2.

  20. Complications Requiring Cochlear Reimplantation

    Directory of Open Access Journals (Sweden)

    Seied Basir Hashemi

    2011-01-01

    Conclusion:  In view of the fact that a significant proportion of the patients who complained of otalgia had no pathologies in the ear, thorough physical examination in adjacent structures especially teeth should be performed and malignancies should be considered as a possible etiology of otalgia.

  1. Recent advances in laser microprobe mass analysis (LAMMA) of inner ear tissue

    International Nuclear Information System (INIS)

    Meyer zum Gottesberge-Orsulakova, A.; Kaufmann, R.

    1985-01-01

    Maintenance of ionic gradients within the various fluids compartments of the inner ear requires transport active cellular systems at different locations. LAMMA analysis is ideally suited for detection of ions in microquantity on cellular levels overcoming many technical difficulties. The present paper summarizes the results of microprobe analysis obtained with laser induced mass spectrometry (LAMMA) supplemented by X-ray microprobe analysis of epithelial cell layers adjacent to the endolymphatic space in the cochlear duct, in the vestibular organ and in the endolymphatic sac. The possible role of inner ear as well as ocular melanin in the mechanisms of active ion transport is discussed

  2. [Constitute, imaging and auditory characteristics of pediatric patients with congenital malformations of inner ear in sensorineural hearing loss].

    Science.gov (United States)

    Li, Youjin; Yang, Jun; Li, Yun

    2011-01-01

    To analyze the constitute, imaging and auditory characteristics of pediatric patients with congenital malformations of inner ear in sensorineural hearing loss(SNHL). Imaging and auditory data of 125 cases (225 ears) in 860 pediatric patients with congenital SNHL who referred to ENT department of Shanghai Children Medical Center from February 2005 to January 2010 were retrospectively studied. Congenital malformations of inner ear accounted for 14.5% in 860 pediatric patients with congenital SNHL. Bilateral ear was involved in 98 cases (78.4%), unilateral in 27 cases (21.6%). One hundred and sixty-seven ears (74.2%) were identified as profound deafness, 36 ears (16%) severe deafness and 22 ears (9.8%) moderate deafness in 225 ears, respectively. In present group, large vestibular aqueduct (75.6%) was the most common and next was vestibular deformity (32%), then cochleovestibular deformity (23.1%). Mondini deformity (55.8%) was the most common and common cavity deformity (28.9%) next in cochleovestibular deformity. Profound deafness in cochlea involved congenital malformations of inner ear was significantly more than those in no cochlea involved malformations. The results are of importance for understanding the constitute of congenital malformations of inner ear in pediatric patients with congenital SNHL in China, for etiological diagnosis of congenital SNHL, for intervention including hearing aids or cochlear implant and prognosis.

  3. Cochlear implantation in autistic children with profound sensorineural hearing loss.

    Science.gov (United States)

    Lachowska, Magdalena; Pastuszka, Agnieszka; Łukaszewicz-Moszyńska, Zuzanna; Mikołajewska, Lidia; Niemczyk, Kazimierz

    2016-11-19

    Cochlear implants have become the method of choice for the treatment of severe-to-profound hearing loss in both children and adults. Its benefits are well documented in the pediatric and adult population. Also deaf children with additional needs, including autism, have been covered by this treatment. The aim of this study was to assess the benefits from cochlear implantation in deafened children with autism as the only additional disability. This study analyzes data of six children. The follow-up time was at least 43 months. The following data were analyzed: medical history, reaction to music and sound, Ling's six sounds test, onomatopoeic word test, reaction to spoken child's name, response to requests, questionnaire given to parents, sound processor fitting sessions and data. After cochlear implantation each child presented other communication skills. In some children, the symptoms of speech understanding were observed. No increased hyperactivity associated with daily use cochlear implant was observed. The study showed that in autistic children the perception is very important for a child's sense of security and makes contact with parents easier. Our study showed that oral communication is not likely to be a realistic goal in children with cochlear implants and autism. The implantation results showed benefits that varied among those children. The traditional methods of evaluating the results of cochlear implantation in children with autism are usually insufficient to fully assess the functional benefits. These benefits should be assessed in a more comprehensive manner taking into account the limitations of communication resulting from the essence of autism. It is important that we share knowledge about these complex children with cochlear implants. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  4. Cochlear implantation in autistic children with profound sensorineural hearing loss

    Directory of Open Access Journals (Sweden)

    Magdalena Lachowska

    Full Text Available Abstract Introduction Cochlear implants have become the method of choice for the treatment of severe-to-profound hearing loss in both children and adults. Its benefits are well documented in the pediatric and adult population. Also deaf children with additional needs, including autism, have been covered by this treatment. Objective The aim of this study was to assess the benefits from cochlear implantation in deafened children with autism as the only additional disability. Methods This study analyzes data of six children. The follow-up time was at least 43 months. The following data were analyzed: medical history, reaction to music and sound, Ling's six sounds test, onomatopoeic word test, reaction to spoken child's name, response to requests, questionnaire given to parents, sound processor fitting sessions and data. Results After cochlear implantation each child presented other communication skills. In some children, the symptoms of speech understanding were observed. No increased hyperactivity associated with daily use cochlear implant was observed. The study showed that in autistic children the perception is very important for a child's sense of security and makes contact with parents easier. Conclusion Our study showed that oral communication is not likely to be a realistic goal in children with cochlear implants and autism. The implantation results showed benefits that varied among those children. The traditional methods of evaluating the results of cochlear implantation in children with autism are usually insufficient to fully assess the functional benefits. These benefits should be assessed in a more comprehensive manner taking into account the limitations of communication resulting from the essence of autism. It is important that we share knowledge about these complex children with cochlear implants.

  5. Roles of the Contralateral Efferent Reflex in Hearing Demonstrated with Cochlear Implants.

    Science.gov (United States)

    Lopez-Poveda, Enrique A; Eustaquio-Martín, Almudena; Stohl, Joshua S; Wolford, Robert D; Schatzer, Reinhold; Wilson, Blake S

    2016-01-01

    Our two ears do not function as fixed and independent sound receptors; their functioning is coupled and dynamically adjusted via the contralateral medial olivocochlear efferent reflex (MOCR). The MOCR possibly facilitates speech recognition in noisy environments. Such a role, however, is yet to be demonstrated because selective deactivation of the reflex during natural acoustic listening has not been possible for human subjects up until now. Here, we propose that this and other roles of the MOCR may be elucidated using the unique stimulus controls provided by cochlear implants (CIs). Pairs of sound processors were constructed to mimic or not mimic the effects of the contralateral MOCR with CIs. For the non-mimicking condition (STD strategy), the two processors in a pair functioned independently of each other. When configured to mimic the effects of the MOCR (MOC strategy), however, the two processors communicated with each other and the amount of compression in a given frequency channel of each processor in the pair decreased with increases in the output energy from the contralateral processor. The analysis of output signals from the STD and MOC strategies suggests that in natural binaural listening, the MOCR possibly causes a small reduction of audibility but enhances frequency-specific inter-aural level differences and the segregation of spatially non-overlapping sound sources. The proposed MOC strategy could improve the performance of CI and hearing-aid users.

  6. Middle Ear Infections and Ear Tube Surgery (For Parents)

    Science.gov (United States)

    ... ears.) Infection Bacteria or viruses can enter the middle ear through the eustachian tube and cause an infection — this often happens when a child has had a cold or other respiratory infection. ...

  7. Aspects of temporal bone anatomy and pathology in conjunction with cochlear implant surgery

    Energy Technology Data Exchange (ETDEWEB)

    Stjernholm, Christina [Karolinska Inst., Stockholm (Sweden). Soedersjukhuset

    2003-07-01

    Cochlear implantation is a treatment for patients with severe sensorineural hearing loss/deafness, who get no help from ordinary hearing aids. The cochlear implant is surgically placed under the skin near the ear and a very thin electrode array is introduced into the cochlea of the inner ear, where it stimulates the remaining nerve fibers. The operation is complicated; it is performed with the aid of a microscope, and involves drilling very close to vital vessels and important nerves. High resolution computed tomography (CT) of the temporal bone is a part of the preoperative evaluation preceding cochlear implantation. It is a method for visualizing the bony structures of the middle and inner ear - to diagnose pathology and to describe the anatomy. The first work concerns CT of the temporal bone and cochlear implant surgery in children with CHARGE association. This is a rare condition with multiple congenital abnormalities, sometimes lethal. Children with CHARGE have different combinations of disabilities, of which impairments of vision and hearing, as well as balance problems and facial palsy can lead to developmental delay. There have been few reports of radiological temporal bone changes and none of cochlear implant surgery for this group. The work includes a report of the findings on preoperative CT and at surgery, as well as postimplant results in two children. A review of the latest diagnostic criteria of CHARGE and the temporal bone changes found in international literature is also included. The conclusion was that certain combinations of temporal bone changes in CHARGE are, if not specific, at least extremely rare in other materials. CT can visualize these changes and be used as a diagnostic tool. This is important, since some of the associated disabilities are not so obvious from the start. Early treatment is vital for the child's development. This work also shows that cochlear implantation may help some of these often very isolated children to

  8. Aspects of temporal bone anatomy and pathology in conjunction with cochlear implant surgery

    International Nuclear Information System (INIS)

    Stjernholm, Christina

    2003-01-01

    Cochlear implantation is a treatment for patients with severe sensorineural hearing loss/deafness, who get no help from ordinary hearing aids. The cochlear implant is surgically placed under the skin near the ear and a very thin electrode array is introduced into the cochlea of the inner ear, where it stimulates the remaining nerve fibers. The operation is complicated; it is performed with the aid of a microscope, and involves drilling very close to vital vessels and important nerves. High resolution computed tomography (CT) of the temporal bone is a part of the preoperative evaluation preceding cochlear implantation. It is a method for visualizing the bony structures of the middle and inner ear - to diagnose pathology and to describe the anatomy. The first work concerns CT of the temporal bone and cochlear implant surgery in children with CHARGE association. This is a rare condition with multiple congenital abnormalities, sometimes lethal. Children with CHARGE have different combinations of disabilities, of which impairments of vision and hearing, as well as balance problems and facial palsy can lead to developmental delay. There have been few reports of radiological temporal bone changes and none of cochlear implant surgery for this group. The work includes a report of the findings on preoperative CT and at surgery, as well as postimplant results in two children. A review of the latest diagnostic criteria of CHARGE and the temporal bone changes found in international literature is also included. The conclusion was that certain combinations of temporal bone changes in CHARGE are, if not specific, at least extremely rare in other materials. CT can visualize these changes and be used as a diagnostic tool. This is important, since some of the associated disabilities are not so obvious from the start. Early treatment is vital for the child's development. This work also shows that cochlear implantation may help some of these often very isolated children to communicate

  9. Otic ablation of smoothened reveals direct and indirect requirements for Hedgehog signaling in inner ear development

    OpenAIRE

    Brown, Alexander S.; Epstein, Douglas J.

    2011-01-01

    In mouse embryos lacking sonic hedgehog (Shh), dorsoventral polarity within the otic vesicle is disrupted. Consequently, ventral otic derivatives, including the cochlear duct and saccule, fail to form, and dorsal otic derivatives, including the semicircular canals, endolymphatic duct and utricle, are malformed or absent. Since inner ear patterning and morphogenesis are heavily dependent on extracellular signals derived from tissues that are also compromised by the loss of Shh, the extent to w...

  10. Data Descriptor: A multiscale imaging and modelling dataset of the human inner ear

    DEFF Research Database (Denmark)

    Gerber, Nicolas; Reyes, Mauricio; Barazzetti, Livia

    2017-01-01

    Understanding the human inner ear anatomy and its internal structures is paramount to advance hearing implant technology. While the emergence of imaging devices allowed researchers to improve understanding of intracochlear structures, the difficulties to collect appropriate data has resulted...... of the cochlea used to leverage scientific hypotheses. It is of relevance to anatomists, audiologists, computer scientists in the different domains of image analysis, computer simulations, imaging formation, and for biomedical engineers designing new strategies for cochlear implantations, electrode design...

  11. Measuring directional characteristics of in-ear recording devices

    DEFF Research Database (Denmark)

    Christensen, Flemming; Hoffmann, Pablo F.; Hammershøi, Dorte

    2013-01-01

    . The pinna and thereby also the natural sound transmission are altered by the inserted device. This paper presents a methodology for accurately measuring the directional dependent transfer functions of such in-ear devices. Pilot measurements on a commercial available device are presented and possibilities......With the availability of small in-ear headphones and miniature microphones it is possible to construct combined in-ear devices for binaural recording and playback. When mounting a microphone on the outside of an insert earphone the microphone position deviates from ideal positions in the ear canal...

  12. Audiometric evaluation short and medium term in cochlear implants.

    Science.gov (United States)

    Alonso-Luján, Laura R; Gutiérrez-Farfán, Ileana; Luna-Reyes, Francisco A; Chamlati-Aguirre, Laura E; Durand Rivera, Alfredo

    2014-01-01

    Our purpose is report the results of cochlear implant program in this Institute, since our first surgery from November 2007, until December 2012. A cross-sectional study, observational, descriptive, analyzing the information about thresholds before and after implantation, using patients files (diagnosis, onset of hearing loss, brainstem auditory evoked potential (BAEP), computed tomography (CT), magnetic resonance imaging (MRI), implanted ear, brand and model of cochlear implants (CI) and audiometric studies before and after the CI. We report the evolution of 68 patients, age ranged 1 year 8 months to 39 years 3 months old. 94% patients (n = 64) had pre-lingual hearing loss being hereditary non-syndromic hearing loss the most common etiology (29.4%). 100% patients had auditory brainstem responses showing bilateral profound hearing loss, in the 77.9% type A tympanograms were obtained (Jerger's classification), and 100% had absence of stapedial reflexes and otoacoustic emissions with low reproducibility. CT reported as normal in 85.2% of patients, the findings: 5.8% had chronic mastoiditis changes, other findings reported in 1.4% of patients were: digastric right facial nerve, facial nerve canal dehiscence, enlarged vestibular aqueduct, occupation and poor pneumatization of mastoid air cells, lateral semicircular canals agenesis, incomplete partition of the cochlea with wide vestibular and vestibular aqueduct dilatation. Most frequent MR findings of skull with cerebellopontine angle approach were vascular loops of internal auditory canals unilaterally. In 10.2%, 55.8% of patients (n = 38) were implanted in the right ear, 56 (82.3%) with a CI from Advanced Bionics, HiRes 90K model, the remaining with Cochlear, Freedom and Nucleus 5 models. Developments in CI results by audiometric tests: prior to placement was 106.2 dB averages at frequencies assessed, one month later 62.4 dB, at 6 months 44 dB, and with satisfactory threshold 32.9 dB. 55.8% of patients (n = 38) with

  13. The effect of early auditory experience on the spatial listening skills of children with bilateral cochlear implants.

    Science.gov (United States)

    Killan, Catherine F; Royle, Nicola; Totten, Catherine L; Raine, Christopher H; Lovett, Rosemary E S

    2015-12-01

    Both electrophysiological and behavioural studies suggest that auditory deprivation during the first months and years of life can impair listening skills. Electrophysiological studies indicate that 3½ years may be a critical age for the development of symmetrical cortical responses in children using bilateral cochlear implants. This study aimed to examine the effect of auditory experience during the first 3½ years of life on the behavioural spatial listening abilities of children using bilateral cochlear implants, with reference to normally hearing children. Data collected during research and routine clinical testing were pooled to compare the listening skills of children with bilateral cochlear implants and different periods of auditory deprivation. Children aged 4-17 years with bilateral cochlear implants were classified into three groups. Children born profoundly deaf were in the congenital early bilateral group (received bilateral cochlear implants aged ≤3½ years, n=28) or congenital late bilateral group (received first implant aged ≤3½ years and second aged >3½ years, n=38). Children with some bilateral acoustic hearing until the age of 3½ years, who subsequently became profoundly deaf and received bilateral cochlear implants, were in the acquired/progressive group (n=16). There were 32 children in the normally hearing group. Children completed tests of sound-source localization and spatial release from masking (a measure of the ability to use both ears to understand speech in noise). The acquired/progressive group localized more accurately than both groups of congenitally deaf children (p<0.05). All three groups of children with cochlear implants showed similar spatial release from masking. The normally hearing group localized more accurately than all groups with bilateral cochlear implants and displayed more spatial release from masking than the congenitally deaf groups on average (p<0.05). Children with bilateral cochlear implants and early

  14. Complications in cochlear implantation at the Clinical Center of Vojvodina

    Directory of Open Access Journals (Sweden)

    Dankuc Dragan

    2015-01-01

    Full Text Available Introduction. The first modern cochlear implantation in Serbia was performed on November 26, 2002 at the Center for Cochlear Implantation of the Clinic for Ear, Nose and Throat Diseases, Clinical Center of Vojvodina. Objective. The aim of the paper is the analysis of intraoperative and postoperative complications. Major complications include those resulting in the necessity for revision surgery, explantation, reimplantation, severe disease or even lethal outcomes. Minor complications resolve spontaneously or can be managed by conservative therapy and do not require any prolonged hospitalization of the patient. Methods. In the 2002-2013 period, 99 patients underwent surgical procedures and 100 cochlear implants were placed. Both intraoperative and postoperative complications were analyzed in the investigated patient population. Results. The analysis encompassed 99 patients, the youngest and the oldest ones being one year old and 61 years old, respectively. The complications were noticed in 11 patients, i.e. in 10.5% of 105 surgical procedures. The majority of procedures (89.5% were not accompanied by any post-surgical complications. Unsuccessful implantation in a single-step procedure (4.04% and transient facial nerve paralysis can be considered most frequent among our patients, whereas cochlear ossification (1.01% and transient ataxia (2.02% occurred rarely. Stimulation of the facial nerve (1.01%, intraoperative perilymph liquid gusher (1.01%, device failure and late infections (1.01% were recorded extremely rarely. Conclusion. Complications such as electrode extrusion, skin necrosis over the implant or meningitis, which is considered the most severe postoperative complication, have not been recorded at our Center since the very beginning. Absence of postoperative meningitis in patients treated at the Center can be attributed to timely pneumococcal vaccination of children.

  15. From Ear to Brain

    Science.gov (United States)

    Kimura, Doreen

    2011-01-01

    In this paper Doreen Kimura gives a personal history of the "right-ear effect" in dichotic listening. The focus is on the early ground-breaking papers, describing how she did the first dichotic listening studies relating the effects to brain asymmetry. The paper also gives a description of the visual half-field technique for lateralized stimulus…

  16. Middle Ear Infections

    Science.gov (United States)

    ... to develop a serious illness. What if a child with a middle ear infection is in great pain and discomfort? The mainstay of pain management for AOM is medications such as acetominophen ... before the child's bedtime. Fortunately, by 24 hours about 60 percent ...

  17. Middle ear implants

    Directory of Open Access Journals (Sweden)

    K S Gangadhara Somayaji

    2013-01-01

    Full Text Available Hearing loss is becoming more common in the society living in cities with lot of background noise around, and frequent use of gadgets like mobile phones, MP3s, and IPods are adding to the problem. The loss may involve the conductive or perceptive pathway. Majority of the patients with conductive hearing loss will revert back to normal hearing levels with medical and/or surgical treatment. However, in sensorineural hearing loss, many factors are involved in the management. Though traditionally hearing aids in various forms are the most commonly used modality in managing these patients, there are some drawbacks associated with them. Implantable middle ear amplifiers represent the most recent breakthrough in the management of hearing loss. Middle ear implants are surgically implanted electronic devices that aim to correct hearing loss by stimulating the ossicular chain or middle ear. Of late, they are also being used in the management of congenital conductive hearing loss and certain cases of chronic otitis media with residual hearing loss. The article aims to provide general information about the technology, indications and contraindications, selection of candidates, available systems, and advantages of middle ear implants. (MEI

  18. Middle ear effusion

    African Journals Online (AJOL)

    NJSR

    Abstract. Carcinoma of the breast can metastasise to many organs. Metastasis to the temporal bone is rare and even when it does, it would usually spread to other parts of the body. This is a report of isolated metastasis to the temporal bone with middle ear effusion. Key words: Carcinoma, breast, metastasis, temporal bone, ...

  19. Noise-induced cochlear synaptopathy: Past findings and future studies.

    Science.gov (United States)

    Kobel, Megan; Le Prell, Colleen G; Liu, Jennifer; Hawks, John W; Bao, Jianxin

    2017-06-01

    For decades, we have presumed the death of hair cells and spiral ganglion neurons are the main cause of hearing loss and difficulties understanding speech in noise, but new findings suggest synapse loss may be the key contributor. Specifically, recent preclinical studies suggest that the synapses between inner hair cells and spiral ganglion neurons with low spontaneous rates and high thresholds are the most vulnerable subcellular structures, with respect to insults during aging and noise exposure. This cochlear synaptopathy can be "hidden" because this synaptic loss can occur without permanent hearing threshold shifts. This new discovery of synaptic loss opens doors to new research directions. Here, we review a number of recent studies and make suggestions in two critical future research directions. First, based on solid evidence of cochlear synaptopathy in animal models, it is time to apply molecular approaches to identify the underlying molecular mechanisms; improved understanding is necessary for developing rational, effective therapies against this cochlear synaptopathy. Second, in human studies, the data supporting cochlear synaptopathy are indirect although rapid progress has been made. To fully identify changes in function that are directly related this hidden synaptic damage, we argue that a battery of tests including both electrophysiological and behavior tests should be combined for diagnosis of "hidden hearing loss" in clinical studies. This new approach may provide a direct link between cochlear synaptopathy and perceptual difficulties. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Exploring the experiences of teenagers with cochlear implants.

    Science.gov (United States)

    Watson, Victoria; Verschuur, Carl; Lathlean, Judith

    2016-11-01

    Teenage cochlear implant users' perceptions of deafness, surgery, fitting of the device and life as a cochlear implant wearer were explored in order to gain a more comprehensive understanding of teenagers' experiences of living with the device. Semi-structured in-depth interviews were undertaken and analysed using thematic analysis. Ten teenagers aged 14-16 years with at least one cochlear implant were interviewed. Seven teenagers experienced great pre-operative anxiety and two reported significant post-operative pain. Four of the teenagers described a mismatch between their expectations and the disappointing reality of adjusting to the device. However, all the teenagers reported an enhanced sense of well-being as a result of being able to interact more easily with their world around them. The teenagers differed in the extent to which they identified with the hearing and deaf world. Despite the early challenges, over time the teenagers experienced many functional and psychosocial benefits. Most felt their lives were now easier as a result of the cochlear implant(s). They described complex, flexible identities. By giving prominence to the teenagers' voices this study has added new knowledge concerning their experience of surgery. The findings also more fully revealed the challenges of adjusting to the device and the impact of having a cochlear implant on the teenagers' identities. Clinical recommendations are made to address the gaps in service highlighted by these findings.

  1. Cochlear injury and adaptive plasticity of the auditory cortex

    Directory of Open Access Journals (Sweden)

    ANNA R. eFETONI

    2015-02-01

    Full Text Available Growing evidence suggests that cochlear stressors as noise exposure and aging can induce homeostatic/maladaptive changes in the central auditory system from the brainstem to the cortex. Studies centered on such changes have revealed several mechanisms that operate in the context of sensory disruption after insult (noise trauma, drug- or age-related injury. The oxidative stress is central to current theories of induced sensory neural hearing loss and aging, and interventions to attenuate the hearing loss are based on antioxidant agent. The present review addresses the recent literature on the alterations in hair cells and spiral ganglion neurons due to noise-induced oxidative stress in the cochlea, as well on the impact of cochlear damage on the auditory cortex neurons. The emerging image emphasizes that noise-induced deafferentation and upward spread of cochlear damage is associated with the altered dendritic architecture of auditory pyramidal neurons. The cortical modifications may be reversed by treatment with antioxidants counteracting the cochlear redox imbalance. These findings open new therapeutic approaches to treat the functional consequences of the cortical reorganization following cochlear damage.

  2. Cochlear implanted children: Linguistic outcomes

    OpenAIRE

    Lynce, Sofia; Marques, Sofia; Paço, João; Mineiro, Ana

    2017-01-01

    The present exploratory study aims at exploring expressive linguistics abilities of cochlear-implanted children by testing spontaneous speech samples. For this purpose, Mean Length of Utterance in words will be measured and the productive use of single grammatical morphemes will be analysed. We analysed the spontaneous speech of three deaf Portuguese children with cochlear implants and three normal-hearing children paired case by case, taking into account the chronological age, gender and par...

  3. Comparison of electrically evoked compound action potential thresholds and loudness estimates for the stimuli used to program the Advanced Bionics cochlear implant.

    Science.gov (United States)

    Jeon, Eun Kyung; Brown, Carolyn J; Etler, Christine P; O'Brien, Sara; Chiou, Li-Kuei; Abbas, Paul J

    2010-01-01

    In the mid-1990s, Cochlear Corporation introduced a cochlear implant (CI) to the market that was equipped with hardware that made it possible to record electrically evoked compound action potentials (ECAPs) from CI users of all ages. Over the course of the next decade, many studies were published that compared ECAP thresholds with levels used to program the speech processor of the Nucleus CI. In 2001 Advanced Bionics Corporation introduced the Clarion CII cochlear implant (the Clarion CII internal device is also known as the CII Bionic Ear). This cochlear implant was also equipped with a system that allowed measurement of the ECAP. While a great deal is known about how ECAP thresholds compare with the levels used to program the speech processor of the Nucleus CI, relatively few studies have reported comparisons between ECAP thresholds and the levels used to program the speech processor of the Advanced Bionics CI. To explore the relationship between ECAP thresholds and behavioral measures of perceptual dynamic range for the range of stimuli commonly used to program the speech processor of the Advanced Bionics CI. This prospective and experimental study uses correlational and descriptive statistics to define the relationship between ECAP thresholds and perceptual dynamic range measures. Twelve postlingually deafened adults participated in this study. All were experienced users of the Advanced Bionics CI system. ECAP thresholds were recorded using the commercially available SoundWave software. Perceptual measures of threshold (T-level), most comfortable level (M-level), and maximum comfortable level (C-level) were obtained using both "tone bursts" and "speech bursts." The relationship between these perceptual and electrophysiological variables was defined using paired t-tests as well as correlation and linear regression. ECAP thresholds were significantly correlated with the perceptual dynamic range measures studied; however, correlations were not strong. Analysis of

  4. Continued expression of GATA3 is necessary for cochlear neurosensory development.

    Directory of Open Access Journals (Sweden)

    Jeremy S Duncan

    Full Text Available Hair cells of the developing mammalian inner ear are progressively defined through cell fate restriction. This process culminates in the expression of the bHLH transcription factor Atoh1, which is necessary for differentiation of hair cells, but not for their specification. Loss of several genes will disrupt ear morphogenesis or arrest of neurosensory epithelia development. We previously showed in null mutants that the loss of the transcription factor, Gata3, results specifically in the loss of all cochlear neurosensory development. Temporal expression of Gata3 is broad from the otic placode stage through the postnatal ear. It therefore remains unclear at which stage in development Gata3 exerts its effect. To better understand the stage specific effects of Gata3, we investigated the role of Gata3 in cochlear neurosensory specification and differentiation utilizing a LoxP targeted Gata3 line and two Cre lines. Foxg1(Cre∶Gata3(f/f mice show recombination of Gata3 around E8.5 but continue to develop a cochlear duct without differentiated hair cells and spiral ganglion neurons. qRT-PCR data show that Atoh1 was down-regulated but not absent in the duct whereas other hair cell specific genes such as Pou4f3 were completely absent. In addition, while Sox2 levels were lower in the Foxg1(Cre:Gata3(f/f cochlea, Eya1 levels remained normal. We conclude that Eya1 is unable to fully upregulate Atoh1 or Pou4f3, and drive differentiation of hair cells without Gata3. Pax2-Cre∶Gata3(f/f mice show a delayed recombination of Gata3 in the ear relative to Foxg1(Cre:Gata3(f/f . These mice exhibited a cochlear duct containing patches of partially differentiated hair cells and developed only few and incorrectly projecting spiral ganglion neurons. Our conditional deletion studies reveal a major role of Gata3 in the signaling of prosensory genes and in the differentiation of cochlear neurosenory cells. We suggest that Gata3 may act in combination with Eya1, Six1, and

  5. Sub-clinical middle ear malfunctions in elderly patients; prevalence ...

    African Journals Online (AJOL)

    Abstract: Background: Little is known about functioning of the middle ear with advancing age. Objectives: To estimate the prevalence and describe tympanometric patterns of sub-clinical middle ear malfunctions,( S-MEM) in elderly patients. It also assessed clinical factors that could predict S-MEM. Methods: Cross-sectional ...

  6. Transfection using hydroxyapatite nanoparticles in the inner ear via an intact round window membrane in chinchilla

    Energy Technology Data Exchange (ETDEWEB)

    Wu Xuewen; Ding Dalian [Central South University, Department of Otolaryngology Head and Neck Surgery, The Third Xiangya Hospital (China); Jiang Haiyan [State University of New York at Buffalo, Center for Hearing and Deafness (United States); XingXiaowei [Central South University, Department of Otolaryngology Head and Neck Surgery, The Third Xiangya Hospital (China); Huang, Suping [Central South University, State Key Laboratory of Powder Metallurgy (China); Liu Hong [Central South University, Department of Otolaryngology Head and Neck Surgery, The Third Xiangya Hospital (China); Chen Zhedong [Central South University, State Key Laboratory of Powder Metallurgy (China); Sun Hong, E-mail: shjhaj@vip.163.com [Central South University, Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital (China)

    2012-01-15

    Hydroxyapatite nanoparticles (nHAT) are known to have excellent biocompatibility, and have attracted increasing attention as new candidates of non-viral vectors for gene therapy. In our previous studies, nHAT carrying a therapeutic gene and a reporter gene were successfully transfected into the spiral ganglion neurons in the inner ear of guinea pigs in vivo as well as in the cultured cell lines, although the transfection efficiencies were never higher than 30%. In this study, the surface modification of nHAT with polyethylenimine (PEI) was made (PEI-nHAT, diameter = 73.09 {+-} 27.32 nm) and a recombinant plasmid carrying enhanced green fluorescent protein (EGFP) gene and neurotrophin-3 (NT-3) gene was constructed as pEGFPC2-NT3. The PEI modified nHAT and the recombinant plasmid was then connected to form the nHAT-based vector-gene complex (PEI-nHAT-pEGFPC2-NT3). This complex was then placed onto the intact round window membranes of the chinchillas for inner ear transfection. Auditory brainstem response (ABR) was tested to evaluate auditory function. Green fluorescence of EGFP was observed using confocal microscopy 48 h after administering vector-gene complexes. There was no significant threshold shift in tone burst-evoked ABR at any tested frequency. Abundant, condensed green fluorescence was found in dark cells on both sides of the crista and around the macula of the utricle. Scattered EGFP signals were also detected in vestibular hair cells, some Schwann cells in the cochlear spiral ganglion region, some outer pillar cells in the organ of Corti, and a few cells in the stria vascularis. The density of green fluorescence-marked cells was obviously higher in the vestibular dark cell area than in other areas of the inner ear, suggesting that vestibular dark cells may have the ability to actively engulf the nHAT-based vector-gene complexes. Considering the high transfection efficiency in the vestibular system, PEI-nHAT may be a potential vector for gene therapy of

  7. Transfection using hydroxyapatite nanoparticles in the inner ear via an intact round window membrane in chinchilla

    International Nuclear Information System (INIS)

    Wu Xuewen; Ding Dalian; Jiang Haiyan; XingXiaowei; Huang, Suping; Liu Hong; Chen Zhedong; Sun Hong

    2012-01-01

    Hydroxyapatite nanoparticles (nHAT) are known to have excellent biocompatibility, and have attracted increasing attention as new candidates of non-viral vectors for gene therapy. In our previous studies, nHAT carrying a therapeutic gene and a reporter gene were successfully transfected into the spiral ganglion neurons in the inner ear of guinea pigs in vivo as well as in the cultured cell lines, although the transfection efficiencies were never higher than 30%. In this study, the surface modification of nHAT with polyethylenimine (PEI) was made (PEI–nHAT, diameter = 73.09 ± 27.32 nm) and a recombinant plasmid carrying enhanced green fluorescent protein (EGFP) gene and neurotrophin-3 (NT-3) gene was constructed as pEGFPC2–NT3. The PEI modified nHAT and the recombinant plasmid was then connected to form the nHAT-based vector–gene complex (PEI–nHAT–pEGFPC2–NT3). This complex was then placed onto the intact round window membranes of the chinchillas for inner ear transfection. Auditory brainstem response (ABR) was tested to evaluate auditory function. Green fluorescence of EGFP was observed using confocal microscopy 48 h after administering vector–gene complexes. There was no significant threshold shift in tone burst-evoked ABR at any tested frequency. Abundant, condensed green fluorescence was found in dark cells on both sides of the crista and around the macula of the utricle. Scattered EGFP signals were also detected in vestibular hair cells, some Schwann cells in the cochlear spiral ganglion region, some outer pillar cells in the organ of Corti, and a few cells in the stria vascularis. The density of green fluorescence-marked cells was obviously higher in the vestibular dark cell area than in other areas of the inner ear, suggesting that vestibular dark cells may have the ability to actively engulf the nHAT-based vector–gene complexes. Considering the high transfection efficiency in the vestibular system, PEI–nHAT may be a potential vector for

  8. Bringing Hearing to the Deaf - Cochlear Implants: A Technical and Personal Account

    Energy Technology Data Exchange (ETDEWEB)

    Shipsey, Ian (Purdue University)

    2003-12-17

    Cochlear implants are the first device to successfully restore neural function. They have instigated a popular but controversial revolution in the treatment of deafness and they serve as a model for research in neuroscience and biomedical engineering. In this talk the physiology of natural hearing will be reviewed from the perspective of a physicist, and the function of cochlear implants will be described in the context of historical treatments, electrical engineering, psychophysics, clinical evaluation of efficacy and personal experience. The social implications of cochlear implantation and the future outlook for auditory prostheses will also be discussed.

  9. Inner ear anomalies seen on CT images in people with Down syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Intrapiromkul, Jarunee; Aygun, Nafi; Yousem, David M. [The Johns Hopkins Medical Institutions, The Russell H. Morgan Department of Radiology and Radiological Sciences, Baltimore, MD (United States); Tunkel, David E. [The Johns Hopkins Medical Institutions, Department of Otolaryngology-Head and Neck Surgery, Baltimore, MD (United States); Carone, Marco [University of California, Division of Biostatistics, School of Public Health, Berkeley, CA (United States)

    2012-12-15

    Although dysplasia of inner ear structures in Down syndrome has been reported in several histopathological studies, the imaging findings have not been widely studied. To evaluate the prevalence and clinical significance of inner ear anomalies detected on CT images in patients with Down syndrome. The temporal bone CT images of patients with Down syndrome were assessed for inner ear anomalies; clinical notes and audiograms were reviewed for hearing loss. Logistic regression models were employed to identify which CT findings were associated with sensorineural hearing loss (SNHL). Inner ear anomalies were observed in 74.5% (38/51) of patients. Malformed bone islands of lateral semicircular canal (LSCC), narrow internal auditory canals (IACs), cochlear nerve canal stenoses, semicircular canal dehiscence (SCCD), and enlarged vestibular aqueducts were detected in 52.5% (53/101), 24.5% (25/102), 21.4% (21/98), 8.8% (9/102) and 2% (2/101) of patients' ears, respectively. IAC stenosis had the highest odds ratio (OR = 5.37, 95% CI: 1.0-28.9, P = 0.05) for SNHL. Inner ear anomalies occurred in 74.5% of our population, with malformed (<3 mm) bone island of LSCC being the most common (52.5%) anomaly. Narrow IAC was seen in 24.5% of patients with Down syndrome and in 57.1% of ears with SNHL. High-resolution CT is a valuable for assessing the cause of hearing loss in people with Down syndrome. (orig.)

  10. Inner ear anomalies seen on CT images in people with Down syndrome

    International Nuclear Information System (INIS)

    Intrapiromkul, Jarunee; Aygun, Nafi; Yousem, David M.; Tunkel, David E.; Carone, Marco

    2012-01-01

    Although dysplasia of inner ear structures in Down syndrome has been reported in several histopathological studies, the imaging findings have not been widely studied. To evaluate the prevalence and clinical significance of inner ear anomalies detected on CT images in patients with Down syndrome. The temporal bone CT images of patients with Down syndrome were assessed for inner ear anomalies; clinical notes and audiograms were reviewed for hearing loss. Logistic regression models were employed to identify which CT findings were associated with sensorineural hearing loss (SNHL). Inner ear anomalies were observed in 74.5% (38/51) of patients. Malformed bone islands of lateral semicircular canal (LSCC), narrow internal auditory canals (IACs), cochlear nerve canal stenoses, semicircular canal dehiscence (SCCD), and enlarged vestibular aqueducts were detected in 52.5% (53/101), 24.5% (25/102), 21.4% (21/98), 8.8% (9/102) and 2% (2/101) of patients' ears, respectively. IAC stenosis had the highest odds ratio (OR = 5.37, 95% CI: 1.0-28.9, P = 0.05) for SNHL. Inner ear anomalies occurred in 74.5% of our population, with malformed (<3 mm) bone island of LSCC being the most common (52.5%) anomaly. Narrow IAC was seen in 24.5% of patients with Down syndrome and in 57.1% of ears with SNHL. High-resolution CT is a valuable for assessing the cause of hearing loss in people with Down syndrome. (orig.)

  11. Conductive Hearing Loss Caused by Third-Window Lesions of the Inner Ear

    Science.gov (United States)

    Merchant, Saumil N.; Rosowski, John J.

    2008-01-01

    Background Various authors have described conductive hearing loss (CHL), defined as an air-bone gap on audiometry, in patients without obvious middle ear pathologic findings. Recent investigations have suggested that many of these cases are due to disorders of the inner ear, resulting in pathologic third windows. Objective To provide an overview of lesions of the inner ear resulting in a CHL due to a third-window mechanism. The mechanism of the CHL is explained along with a classification scheme for these disorders. We also discuss methods for diagnosis of these disorders. Data Sources The data were compiled from a review of the literature and recent published research on middle and inner ear mechanics from our laboratory. Conclusion A number of disparate disorders affecting the labyrinth can produce CHL by acting as a pathologic third window in the inner ear. The common denominator is that these conditions result in a mobile window on the scala vestibuli side of the cochlear partition. The CHL results by the dual mechanism of worsening of air conduction thresholds and improvement of bone conduction thresholds. Such lesions may be anatomically discrete or diffuse. Anatomically discrete lesions may be classified by location: semicircular canals (superior, lateral, or posterior canal dehiscence), bony vestibule (large vestibular aqueduct syndrome, other inner ear malformations), or the cochlea (carotid-cochlear dehiscence, X-linked deafness with stapes gusher, etc.). An example of an anatomically diffuse lesion is Paget disease, which may behave as a distributed or diffuse third window. Third-window lesions should be considered in the differential diagnosis of CHL in patients with an intact tympanic membrane and an aerated, otherwise healthy, middle ear. Clues to suspect such a lesion include a low-frequency air-bone gap with supranormal thresholds for bone conduction, and presence of acoustic reflexes, vestibular evoked myogenic responses, or otoacoustic emission

  12. Aspects of Music with Cochlear Implants – Music Listening Habits and Appreciation in Danish Cochlear Implant Users

    DEFF Research Database (Denmark)

    Petersen, Bjørn; Hansen, Mads; Sørensen, Stine Derdau

    Cochlear implant users differ significantly from their normal hearing peers when it comes to perception of music. Several studies have shown that structural features – such as rhythm, timbre, and pitch – are transmitted less accurately through an implant. However, we cannot predict personal...... enjoyment of music solely as a function of accuracy of perception. But can music be pleasant with a cochlear implant at all? Our aim here was to gather information of both music enjoyment and listening habits before the onset of hearing loss and post-operation from a large, representative sample of Danish...... recipients. A hundred and sixty three adult cochlear implant users (101 females, 62 males) completed a survey containing questions about musical background, listening habits, and music enjoyment. The results indicate a wide range of success with music, but in general, the results show that the CI users enjoy...

  13. Anatomy, Physiology and Function of the Auditory System

    Science.gov (United States)

    Kollmeier, Birger

    The human ear consists of the outer ear (pinna or concha, outer ear canal, tympanic membrane), the middle ear (middle ear cavity with the three ossicles malleus, incus and stapes) and the inner ear (cochlea which is connected to the three semicircular canals by the vestibule, which provides the sense of balance). The cochlea is connected to the brain stem via the eighth brain nerve, i.e. the vestibular cochlear nerve or nervus statoacusticus. Subsequently, the acoustical information is processed by the brain at various levels of the auditory system. An overview about the anatomy of the auditory system is provided by Figure 1.

  14. Hydrogel coated and dexamethasone releasing cochlear implants: quantification of fibrosis in guinea pigs and evaluation of insertion forces in a human cochlea model.

    Science.gov (United States)

    Wrzeszcz, Antonina; Steffens, Melanie; Balster, Sven; Warnecke, Athanasia; Dittrich, Barbara; Lenarz, Thomas; Reuter, Günter

    2015-01-01

    The insertion of cochlear implants (CIs) often causes fibrous tissue growth around the electrode, which leads to attenuation of function of CIs. Inhibition of fibrosis in vivo using dexamethasone (Dex) released from the implant base material (polydimethylsiloxane [PDMS]) coated with a protein repelling hydrogel (star-shaped polyethylene glycol prepolymer, sPEG) was, therefore, the aim of the study. PDMS filaments with Dex or sPEG were implanted into guinea pigs. The hearing status after implantation did not differ significantly in the treated groups. Using confocal laser scanning microscopy in transparent whole mount preparations, Dex, Dex/sPEG, as well as sPEG showed a tendency toward reduced formation of connective tissue around the implant. To apply such coatings for glass fibers for optical stimulation of the inner ear, insertion forces were measured into a human scala tympani model using fibers with sPEG coating. The results show that the hydrogel did not reduce insertion forces compared to the uncoated samples. However, PDMS-embedded fibers provide comparable insertion forces and depth to those measured with conventional CI electrodes, demonstrating the suitability of laser fibers for a minimal traumatic cochlear implantation. © 2014 Wiley Periodicals, Inc.

  15. Forbigående tab af balancefunktionen efter cochlear implantation

    DEFF Research Database (Denmark)

    Hviid Korsager, Leise Elisabeth; Schmidt, Jesper; Faber, Christian

    2017-01-01

    Loss of vestibular function is a common side effect to cochlear implant (CI) surgery. We present a patient who experienced balance problems and showed a reduced vestibulo-ocular reflex (VOR) gain (0.47 ± 0.10) combined with saccades in the horizontal semicircular canals demonstrated by the video...

  16. Patient Specific Simulation for Planning of Cochlear Implantation Surgery

    DEFF Research Database (Denmark)

    Vera, Sergio; Perez, Frederic; Balust, Clara

    2014-01-01

    Cochlear implantation is a surgical procedure that can restore the hearing capabilities to patients with severe or complete functional loss. However, the level of restoration varies highly between subjects and depends on patient-specific factors. This paper presents a software application for pla...

  17. Fgf3 and Fgf16 expression patterns define spatial and temporal domains in the developing chick inner ear.

    Science.gov (United States)

    Olaya-Sánchez, Daniel; Sánchez-Guardado, Luis Óscar; Ohta, Sho; Chapman, Susan C; Schoenwolf, Gary C; Puelles, Luis; Hidalgo-Sánchez, Matías

    2017-01-01

    The inner ear is a morphologically complex sensory structure with auditory and vestibular functions. The developing otic epithelium gives rise to neurosensory and non-sensory elements of the adult membranous labyrinth. Extrinsic and intrinsic signals manage the patterning and cell specification of the developing otic epithelium by establishing lineage-restricted compartments defined in turn by differential expression of regulatory genes. FGF3 and FGF16 are excellent candidates to govern these developmental events. Using the chick inner ear, we show that Fgf3 expression is present in the borders of all developing cristae. Strong Fgf16 expression was detected in a portion of the developing vertical and horizontal pouches, whereas the cristae show weaker or undetected Fgf16 expression at different developmental stages. Concerning the rest of the vestibular sensory elements, both the utricular and saccular maculae were Fgf3 positive. Interestingly, strong Fgf16 expression delimited these Fgf16-negative sensory patches. The Fgf3-negative macula neglecta and the Fgf3-positive macula lagena were included within weakly Fgf16-expressing areas. Therefore, different FGF-mediated mechanisms might regulate the specification of the anterior (utricular and saccular) and posterior (neglecta and lagena) maculae. In the developing cochlear duct, dynamic Fgf3 and Fgf16 expression suggests their cooperation in the early specification and later cell differentiation in the hearing system. The requirement of Fgf3 and Fgf16 genes in endolymphatic apparatus development and neurogenesis are discussed. Based on these observations, FGF3 and FGF16 seem to be key signaling pathways that control the inner ear plan by defining epithelial identities within the developing otic epithelium.

  18. Identification of mRNA transcripts and immunohistochemical localization of Na/H exchanger isoforms in gerbil inner ear.

    Science.gov (United States)

    Bond, B R; Ng, L L; Schulte, B A

    1998-09-01

    Recent physiological and pharmacological studies have implicated involvement of the Na/H exchanger (NHE) in regulating inner ear ion homeostasis, but the cellular distribution of this membrane transporter remains unknown. Here reverse transcription and the polymerase chain reaction (RT-PCR) were employed to screen adult gerbil inner ears for mRNA transcripts encoding the four best characterized isoforms of NHE. PCR products spanning selected segments of NHE mRNAs were cloned and sequenced. The putative housekeeping gene NHE-1 was found to be expressed and the 459 bp product shared 98.7% amino acid homology with rat sequence. NHE-2, NHE-3 and NHE-4 cDNA transcripts likewise were detected and the PCR products shared 100, 99.4 and 88.9% amino acid homology, respectively, with their rat counterparts. In addition, the cellular distribution of NHE isoforms 1 and 3 was mapped in the gerbil inner ear by immunostaining with polyclonal antisera against rat antigens. In the cochlea, the antiserum against NHE-1 reacted strongly at the basolateral membrane of strial marginal cells as well as with inner and outer hair cells and spiral ganglion neurons. Less intense staining for NHE-1 was present in subpopulations of fibrocytes in the spiral limbus and in inferior and superior areas of the spiral ligament. In the vestibular system dark and transitional cells expressed abundant NHE-1 as did hair cells and vestibular ganglia neurons. Immunostaining with the antiserum against NHE-3 was limited to the apical surface of marginal cells in the stria vascularis. Based on these data, NHE-1 likely functions primarily to maintain intracellular pH levels in cells where it is found in high abundance. NHE-3, on the other hand, possibly participates in the vectorial transcellular movement of Na+ by strial marginal cells thus helping to maintain the extremely low Na+ level in cochlear endolymph.

  19. Cochlear implantation in a bilateral Mondini dysplasia.

    Science.gov (United States)

    Turrini, M; Orzan, E; Gabana, M; Genovese, E; Arslan, E; Fisch, U

    1997-01-01

    We report the speech perception progress and programming procedures of a case of congenital profound deafness and bilateral Mondini dysplasia implanted with a Nucleus 20 + 2 cochlear implant at the age of six. Unclear relations between electrodes array and cochlear partition made implant programming difficult and non-standard procedures were set. Cochlear implantation may give excellent rehabilitative results also in cochleae with malformation.

  20. Balance in children following cochlear implantation.

    Science.gov (United States)

    Kelly, Andrew; Liu, Zhaobo; Leonard, Shanna; Toner, Fearghal; Adams, Mark; Toner, Joseph

    2018-01-01

    To assess the vestibular function of children who had unilateral and bilateral cochlear implants compared with a control group of otherwise healthy children who had not been implanted. Observational case-control study. Posturography was carried out in the form of a Modified Clinical Test of Sensory Interaction on Balance using a Wii Balance Board and the Vestio App on an iPod Touch. Thirty children in total were tested, 10 children in each cohort. Results in the form of root mean square calculations were available for each child. Results showed a significant difference in the vestibular function of implanted children and the non-implanted control group (P < 0.05). As expected, children in all groups had more difficulty maintaining posture with their eyes closed on a compliant surface (P < 0.05). Thirty per cent of children with bilateral and 10% with unilateral cochlear implants were unable to complete testing. Our study demonstrates posturography as an inexpensive, easily operated tool that can be used to assess paediatric vestibular function. It showed a significant difference between the control group and the implanted groups. Further work prompted by this study will include interval post-operative testing to more accurately assess the effect that implantation has on vestibular function.

  1. The development of auditory skills in young children with Mondini dysplasia after cochlear implantation.

    Directory of Open Access Journals (Sweden)

    Xueqing Chen

    Full Text Available The aim of this study is to survey and compare the development of auditory skills in young children with Mondini dysplasia and profoundly-deaf young children with radiologically normal inner ears over a period of 3 years after cochlear implantation. A total of 545 young children (age 7 to 36 months with prelingual, severe to profound hearing loss participated in this study. All children received cochlear implantation. Based on whether or not there was a Mondini dysplasia as diagnosed with CT scanning, the subjects were divided into 2 groups: (A 514 young children with radiologically normal inner ears and (B 31 young children with Mondini dysplasia. The Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS was used to assess the children's auditory skills that include vocalization changes, spontaneous alerting to sounds in everyday living environments, and the ability to derive meaning from sounds. The assessment was performed prior to surgery and at 1, 3, 6, 9, 12, 24, and 36 months after implant device switch-on. The mean scores for overall auditory skills were not significantly different between groups A and B at pre-surgery, 1, 12, 24, and 36 months post-surgery, but were significantly different at 3, 6, and 9 months post-surgery. The mean scores for all auditory skills in children with Mondini dysplasia showed significant improvement over time. The mean scores for the three subcategories of auditory skills in children with Mondini dysplasia also showed significant differences at pre-surgery, 1, 3, 6, and 9 months, however, there were no significant differences at 12, 24, and 36 months. Overall, the auditory skills of young children with Mondini dysplasia developed rapidly after cochlear implantation, in a similar manner to that of young children with radiologically normal inner ears. Cochlear implantation is an effective intervention for young children with Mondini dysplasia.

  2. Development of a multichannel vestibular prosthesis prototype by modification of a commercially available cochlear implant.

    Science.gov (United States)

    Valentin, Nicolas S; Hageman, Kristin N; Dai, Chenkai; Della Santina, Charles C; Fridman, Gene Y

    2013-09-01

    No adequate treatment exists for individuals who remain disabled by bilateral loss of vestibular (inner ear inertial) sensation despite rehabilitation. We have restored vestibular reflexes using lab-built multichannel vestibular prostheses (MVPs) in animals, but translation to clinical practice may be best accomplished by modification of a commercially available cochlear implant (CI). In this interim report, we describe preliminary efforts toward that goal. We developed software and circuitry to sense head rotation and drive a CI's implanted stimulator (IS) to deliver up to 1 K pulses/s via nine electrodes implanted near vestibular nerve branches. Studies in two rhesus monkeys using the modified CI revealed in vivo performance similar to our existing dedicated MVPs. A key focus of our study was the head-worn unit (HWU), which magnetically couples across the scalp to the IS. The HWU must remain securely fixed to the skull to faithfully sense head motion and maintain continuous stimulation. We measured normal and shear force thresholds at which HWU-IS decoupling occurred as a function of scalp thickness and calculated pressure exerted on the scalp. The HWU remained attached for human scalp thicknesses from 3-7.8 mm for forces experienced during routine daily activities, while pressure on the scalp remained below capillary perfusion pressure.

  3. Development of a Multichannel Vestibular Prosthesis Prototype by Modification of a Commercially Available Cochlear Implant

    Science.gov (United States)

    Valentin, Nicolas S.; Hageman, Kristin; Dai, Chenkai; Santina, Charles C. Della; Fridman, Gene Y.

    2014-01-01

    No adequate treatment exists for individuals who remain disabled by bilateral loss of vestibular (inner ear inertial) sensation despite rehabilitation. We have restored vestibular reflexes using lab-built multichannel vestibular prostheses (MVPs) in animals, but translation to clinical practice may be best accomplished by modification of a commercially available cochlear implant (CI). We developed software and circuitry to sense head rotation and drive a CI's implanted stimulator (IS) to deliver up to 1Kpulses/s via 9 electrodes implanted near vestibular nerve branches. Studies in two rhesus monkeys using the modified CI (MCI) revealed in vivo performance similar to our existing dedicated MVPs. Like commercially available CIs, our design uses an external head-worn unit (HWU) that is magnetically coupled across the scalp to the IS. The HWU must remain securely fixed to the skull to faithfully sense head motion with gyroscopes and maintain continuous stimulation. We measured normal and shear force thresholds at which HWU-IS decoupling occurred as a function of scalp thickness and calculated pressure exerted on the scalp. The HWU remained attached across the human scalp thicknesses from 3mm to 7.8mm for forces experienced during routine daily activities, with magnets exerting pressure on the scalp that remains below capillary perfusion pressure. PMID:23649285

  4. Magnetic stem cell targeting to the inner ear

    Science.gov (United States)

    Le, T. N.; Straatman, L.; Yanai, A.; Rahmanian, R.; Garnis, C.; Häfeli, U. O.; Poblete, T.; Westerberg, B. D.; Gregory-Evans, K.

    2017-12-01

    Severe sensorineural deafness is often accompanied by a loss of auditory neurons in addition to injury of the cochlear epithelium and hair cell loss. Cochlear implant function however depends on a healthy complement of neurons and their preservation is vital in achieving optimal results. We have developed a technique to target mesenchymal stem cells (MSCs) to a deafened rat cochlea. We then assessed the neuroprotective effect of systematically delivered MSCs on the survival and function of spiral ganglion neurons (SGNs). MSCs were labeled with superparamagnetic nanoparticles, injected via the systemic circulation, and targeted using a magnetized cochlea implant and external magnet. Neurotrophic factor concentrations, survival of SGNs, and auditory function were assessed at 1 week and 4 weeks after treatments and compared against multiple control groups. Significant numbers of magnetically targeted MSCs (>30 MSCs/section) were present in the cochlea with accompanied elevation of brain-derived neurotrophic factor and glial cell-derived neurotrophic factor levels (p stem cells release neurotrophic factors which results in improved SGN survival and hearing recovery. Combining magnetic cell-based therapy and cochlear implantation may improve cochlear implant function in treating deafness.

  5. Small yet effective: The Ethylene-responsive element binding factor-associated Amphiphilic Repression (EAR) motif

    OpenAIRE

    Kagale, Sateesh; Rozwadowski, Kevin

    2010-01-01

    The Ethylene-responsive element binding factor-associated Amphiphilic Repression (EAR) motif is a small yet distinct regulatory motif that is conserved in many plant transcriptional regulator (TR) proteins associated with diverse biological functions. We have previously established a list of high-confidence Arabidopsis EAR repressors, the EAR repressome, comprising 219 TRs belonging to 21 different TR families. This class of proteins and the sequence context of the EAR motif exhibited a high ...

  6. Gentamicin pharmacokinetics in the chicken inner ear.

    Science.gov (United States)

    Bunting, Eric C; Park, Debra L; Durham, Dianne; Girod, Douglas A

    2004-06-01

    Avians have the unique ability to regenerate cochlear hair cells that are lost due to ototoxins or excessive noise. Many methodological techniques are available to damage the hair cells for subsequent scientific study. A recent method utilizes topical application of an ototoxic drug to the round window membrane. The current study examines the pharmacokinetics of gentamicin in the inner ear of chickens following topical application to the round window membrane or a single systemic high dose given intraperitoneally. Chickens were given gentamicin topically or systemically and survived for 1, 4, 12, 24, or 120 h (controls at 4 and 120 h). Serum and perilymph samples were obtained prior to sacrifice and measured for gentamicin levels. Results revealed higher levels of gentamicin in the perilymph of topically treated chickens than systemically treated chickens, with significant amounts of gentamicin still present in both at the latest survival time of 5 days. As expected, systemically treated chickens had much higher levels of gentamicin in the serum than topically treated chickens. Advantages and disadvantages to each method of drug administration are discussed.

  7. Ear recognition: a complete system

    Science.gov (United States)

    Abaza, Ayman; Harrison, Mary Ann F.

    2013-05-01

    Ear Recognition has recently received significant attention in the literature. Even though current ear recognition systems have reached a certain level of maturity, their success is still limited. This paper presents an efficient complete ear-based biometric system that can process five frames/sec; Hence it can be used for surveillance applications. The ear detection is achieved using Haar features arranged in a cascaded Adaboost classifier. The feature extraction is based on dividing the ear image into several blocks from which Local Binary Pattern feature distributions are extracted. These feature distributions are then fused at the feature level to represent the original ear texture in the classification stage. The contribution of this paper is three fold: (i) Applying a new technique for ear feature extraction, and studying various optimization parameters for that technique; (ii) Presenting a practical ear recognition system and a detailed analysis about error propagation in that system; (iii) Studying the occlusion effect of several ear parts. Detailed experiments show that the proposed ear recognition system achieved better performance (94:34%) compared to other shape-based systems as Scale-invariant feature transform (67:92%). The proposed approach can also handle efficiently hair occlusion. Experimental results show that the proposed system can achieve about (78%) rank-1 identification, even in presence of 60% occlusion.

  8. Cochlear implantation in X-linked deafness - How to manage the surgical challenges.

    Science.gov (United States)

    Saeed, Haroon; Powell, Harry R F; Saeed, Shakeel R

    2016-07-01

    In children with X-linked deafness, cochlear malformations challenge the implant surgeon to avoid electrode insertion into the internal auditory meatus and prevent a continuous cerebrospinal fluid (CSF) leak. We describe our experience of cochlear implantation (CI) in two children with profound hearing loss secondary to X-linked deafness, highlighting safer operative techniques to avoid potential complications. Descriptive cases of two children with X-linked deafness (patient 1 and patient 2) undergoing CI. Peri-operative imaging and work-up to surgery are discussed. Specific operative considerations, post-operative complications and subsequent audiological performance are highlighted. In each case, intra-operative fluoroscopic imaging ensured intra-cochlear insertion of electrodes. Expected CSF gusher was seen in each case which was initially controlled by packing around the cochleostomy and array with temporalis muscle and fascia. Patient 1 developed post-operative meningitis secondary to continuous CSF leak. We avoided further significant CSF leak by planning staged procedures for patient 2, with obliteration of the middle ear cleft and external ear canal (EAC) at the time of implantation. In both patients, bilateral implantation successfully provided hearing thresholds of less than 35 dB in both ears at routine follow up. When planning for CI in children with radiological features of X-linked deafness, intra-operative imaging should be utilized to ensure correct electrode positioning. Traditional methods of stopping a CSF gusher may not suffice. We therefore encourage additional surgical obliteration of the middle ear space and EAC to avoid persistent CSF leak and its associated complications.

  9. Dose-dependent cochlear and vestibular toxicity of trans-tympanic cisplatin in the rat.

    Science.gov (United States)

    Callejo, Angela; Durochat, Amandine; Bressieux, Stéphanie; Saleur, Aurélie; Chabbert, Christian; Domènech Juan, Ivan; Llorens, Jordi; Gaboyard-Niay, Sophie

    2017-05-01

    In vivo studies are needed to study cisplatin ototoxicity and to evaluate candidate protective treatments. Rats and mice are the preferred species for toxicological and pharmacological pre-clinical research, but systemic administration of cisplatin causes high morbidity in these species. We hypothesized that trans-tympanic administration of cisplatin would provide a good model for studying its auditory and vestibular toxicity in the rat. Cisplatin was administered by the trans-tympanic route in one ear (50μl, 0.5-2mg/ml) of rats of both sexes and two different strains. Cochlear toxicity was corroborated by histological means. Vestibular toxicity was demonstrated by behavioral and histological analysis. Cisplatin concentrations were assessed in inner ear after trans-tympanic and i.v. administration. In all experiments, no lethality and only scant body weight loss were recorded. Cisplatin caused dose-dependent cochlear toxicity, as demonstrated by hair cell counts in the apical and middle turns of the cochlea, and vestibular toxicity, as demonstrated by behavioral analysis and hair cell counts in utricles. High concentrations of cisplatin were found in the inner ear after trans-tympanic administration. In comparison, i.v. administration resulted in lower inner ear concentrations. We conclude that trans-tympanic administration provides an easy, reproducible and safe model to study the cochlear and vestibular toxicity of cisplatin in the rat. This route of exposure may be useful to address particular questions on cisplatin induced ototoxicity and to test candidate protective treatments. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Hair cell bundles: flexoelectric motors of the inner ear.

    Directory of Open Access Journals (Sweden)

    Kathryn D Breneman

    Full Text Available Microvilli (stereocilia projecting from the apex of hair cells in the inner ear are actively motile structures that feed energy into the vibration of the inner ear and enhance sensitivity to sound. The biophysical mechanism underlying the hair bundle motor is unknown. In this study, we examined a membrane flexoelectric origin for active movements in stereocilia and conclude that it is likely to be an important contributor to mechanical power output by hair bundles. We formulated a realistic biophysical model of stereocilia incorporating stereocilia dimensions, the known flexoelectric coefficient of lipid membranes, mechanical compliance, and fluid drag. Electrical power enters the stereocilia through displacement sensitive ion channels and, due to the small diameter of stereocilia, is converted to useful mechanical power output by flexoelectricity. This motor augments molecular motors associated with the mechanosensitive apparatus itself that have been described previously. The model reveals stereocilia to be highly efficient and fast flexoelectric motors that capture the energy in the extracellular electro-chemical potential of the inner ear to generate mechanical power output. The power analysis provides an explanation for the correlation between stereocilia height and the tonotopic organization of hearing organs. Further, results suggest that flexoelectricity may be essential to the exquisite sensitivity and frequency selectivity of non-mammalian hearing organs at high auditory frequencies, and may contribute to the "cochlear amplifier" in mammals.

  11. Hair cell bundles: flexoelectric motors of the inner ear.

    Science.gov (United States)

    Breneman, Kathryn D; Brownell, William E; Rabbitt, Richard D

    2009-01-01

    Microvilli (stereocilia) projecting from the apex of hair cells in the inner ear are actively motile structures that feed energy into the vibration of the inner ear and enhance sensitivity to sound. The biophysical mechanism underlying the hair bundle motor is unknown. In this study, we examined a membrane flexoelectric origin for active movements in stereocilia and conclude that it is likely to be an important contributor to mechanical power output by hair bundles. We formulated a realistic biophysical model of stereocilia incorporating stereocilia dimensions, the known flexoelectric coefficient of lipid membranes, mechanical compliance, and fluid drag. Electrical power enters the stereocilia through displacement sensitive ion channels and, due to the small diameter of stereocilia, is converted to useful mechanical power output by flexoelectricity. This motor augments molecular motors associated with the mechanosensitive apparatus itself that have been described previously. The model reveals stereocilia to be highly efficient and fast flexoelectric motors that capture the energy in the extracellular electro-chemical potential of the inner ear to generate mechanical power output. The power analysis provides an explanation for the correlation between stereocilia height and the tonotopic organization of hearing organs. Further, results suggest that flexoelectricity may be essential to the exquisite sensitivity and frequency selectivity of non-mammalian hearing organs at high auditory frequencies, and may contribute to the "cochlear amplifier" in mammals.

  12. Immune-Mediated Inner Ear Disease: Diagnostic and therapeutic approaches.

    Science.gov (United States)

    Penêda, José Ferreira; Lima, Nuno Barros; Monteiro, Francisco; Silva, Joana Vilela; Gama, Rita; Condé, Artur

    2018-03-07

    Immune Mediated Inner Ear Disease (IMIED) is a rare form of sensorineural bilateral hearing loss, usually progressing in weeks to months and responsive to immunosuppressive treatment. Despite recent advances, there is no consensus on diagnosis and optimal treatment. A review of articles on IMIED from the last 10 years was conducted using PubMed ® database. IMIED is a rare disease, mostly affecting middle aged women. It may be a primary ear disease or secondary to autoimmune systemic disease. A dual immune response (both cellular and humoral) seems to be involved. Cochlin may be the inner ear protein targeted in this disease. Distinction from other (core common) forms of neurosensory hearing loss is a challenge. Physical examination is mandatory for exclusion of other causes of hearing loss; audiometry identifies characteristic hearing curves. Laboratory and imaging studies are controversial since no diagnostic marker is available. Despite recent research, IMIED diagnosis remains exclusive. Steroids are the mainstay treatment; other therapies need further investigation. For refractory cases, cochlear implantation is an option and with good relative outcome. Copyright © 2018 Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. Publicado por Elsevier España, S.L.U. All rights reserved.

  13. Inner ear decompression sickness in compressed-air diving.

    Science.gov (United States)

    Klingmann, Christoph

    2012-01-01

    Inner ear decompression sickness (IEDCS) has become more frequently reported in recreational diving. We examined 34 divers after IEDCS and analyzed their dive profiles, pattern of symptoms, time of symptom onset and the association with a right-to left shunt (r/l shunt). Four divers used mixed gas and were excluded from the analysis. Of the remaining 30 divers, 25 presented with isolated IEDCS alone, while five divers had additional skin and neurological symptoms. All divers presented with vertigo (100%), and 12 divers reported additional hearing loss (40%). All symptoms occurred within 120 minutes (median 30 minutes) of ascent. Twenty-two of 30 divers (73.3%) showed a r/l shunt. A possible explanation for the frequent association of a r/l shunt and the dominance of vestibular rather than cochlear symptoms could be attributed to the different blood supply of the inner ear structures and the different size of the labyrinthine compartments. The cochlea has a blood supply up to four times higher than the vestibular part of the inner ear, whereas the vestibular fluid space is 30% larger. The higher prevalence of symptoms referrable to the less well-perfused vestibular organ provides further evidence that persistent local inert gas supersaturation may cause growth of incoming arterial bubbles and may therefore be an important pathophysiological factor in IEDCS.

  14. Aging, Cognitive Decline and Hearing Loss: Effects of Auditory Rehabilitation and Training with Hearing Aids and Cochlear Implants on Cognitive Function and Depression among Older Adults.

    Science.gov (United States)

    Castiglione, Alessandro; Benatti, Alice; Velardita, Carmelita; Favaro, Diego; Padoan, Elisa; Severi, Daniele; Pagliaro, Michela; Bovo, Roberto; Vallesi, Antonino; Gabelli, Carlo; Martini, Alessandro

    2016-01-01

    A growing interest in cognitive effects associated with speech and hearing processes is spreading throughout the scientific community essentially guided by evidence that central and peripheral hearing loss is associated with cognitive decline. For the present research, 125 participants older than 65 years of age (105 with hearing impairment and 20 with normal hearing) were enrolled, divided into 6 groups according to their degree of hearing loss and assessed to determine the effects of the treatment applied. Patients in our research program routinely undergo an extensive audiological and cognitive evaluation protocol providing results from the Digit Span test, Stroop color-word test, Montreal Cognitive Assessment and Geriatric Depression Scale, before and after rehabilitation. Data analysis was performed for a cross-sectional and longitudinal study of the outcomes for the different treatment groups. Each group demonstrated improvement after auditory rehabilitation or training on short- and long-term memory tasks, level of depression and cognitive status scores. Auditory rehabilitation by cochlear implants or hearing aids is effective also among older adults (median age of 74 years) with different degrees of hearing loss, and enables positive improvements in terms of social isolation, depression and cognitive performance. © 2016 The Author(s) Published by S. Karger AG, Basel.

  15. The future of cochlear implants.

    Science.gov (United States)

    Wilson, B S

    1997-08-01

    Remarkable progress has been made in recent years in the design and application of processing strategies for cochlear implants. Most notably, use of the new spectral peak (SPEAK) and continuous interleaved sampling (CIS) strategies have provided large improvements in speech reception performance compared with prior strategies (NIH Consensus Statement, 1995; Skinner et al., 1994a; Wilson et al., 1991). All major manufacturers of multichannel implant systems, including Advanced Bionics Corp., Bionic Systems, Cochlear Pty. Ltd., and Med El, now offer CIS or CIS-like strategies in their speech processors. The SPEAK strategy was developed by Cochlear Pty. Ltd and continues to be one of the options available in that company's devices. The principal purpose of this editorial is to present some of the many possibilities for further improvements in performance. To the extent that such possibilities are realized, implant systems of the future may be quite different from present systems, with different processing strategies, electrode designs, telemetry features, and fitting procedures.

  16. Congenitally Deafblind Children and Cochlear Implants

    DEFF Research Database (Denmark)

    Dammeyer, Jesper Herup

    2008-01-01

    There has been much research conducted demonstrating the positive benefits of cochlear implantation (CI) in children who are deaf. Research on cochlear implantation in children who are both deaf and blind, however, is lacking. The purpose of this article is to present a study of 5 congenitally...... deafblind children who received cochlear implants between 2.2 and 4.2 years of age.  Ratings of video observations were used to measure the children's early communication development with and without the use of their cochlear implants. In addition, parental interviews were used to assess the benefits...... parents perceived regarding their children's cochlear implants. Two examples are included in this article to illustrate the parents' perspectives about cochlear implantation in their deafblind children. Benefits of cochlear implantation in this cohort of children included improved attention and emotional...

  17. Overexpression of SK2 channels enhances efferent suppression of cochlear responses without enhancing noise resistance.

    Science.gov (United States)

    Maison, Stéphane F; Parker, Lisan L; Young, Lucy; Adelman, John P; Zuo, Jian; Liberman, M Charles

    2007-04-01

    Cochlear hair cells express SK2, a small-conductance Ca(2+)-activated K(+) channel thought to act in concert with Ca(2+)-permeable nicotinic acetylcholine receptors (nAChRs) alpha9 and alpha10 in mediating suppressive effects of the olivocochlear efferent innervation. To probe the in vivo role of SK2 channels in hearing, we examined gene expression, cochlear function, efferent suppression, and noise vulnerability in mice overexpressing SK2 channels. Cochlear thresholds, as measured by auditory brain stem responses and otoacoustic emissions, were normal in overexpressers as was overall cochlear morphology and the size, number, and distribution of efferent terminals on outer hair cells. Cochlear expression levels of SK2 channels were elevated eightfold without striking changes in other SK channels or in the alpha9/alpha10 nAChRs. Shock-evoked efferent suppression of cochlear responses was significantly enhanced in overexpresser mice as seen previously in alpha9 overexpresser mice; however, in contrast to alpha9 overexpressers, SK2 overexpressers were not protected from acoustic injury. Results suggest that efferent-mediated cochlear protection is mediated by other downstream effects of ACh-mediated Ca(2+) entry different from those involving SK2-mediated hyperpolarization and the associated reduction in outer hair cell electromotility.

  18. Outcomes and Time to Emergence of Auditory Skills After Cochlear Implantation of Children With Charge Syndrome.

    Science.gov (United States)

    Young, Nancy M; Tournis, Elizabeth; Sandy, Jenelle; Hoff, Stephen R; Ryan, Maura

    2017-09-01

    Review perioperative complications, benefits, and the timeframe over which auditory skills develop in children with CHARGE syndrome who receive a cochlear implant (CI). IRB-approved retrospective chart review of children with CHARGE syndrome who had at least 12 months of cochlear implant use. Tertiary care children's hospital. Twelve children, seven males and five females. Mean age implant = 3.5 years (1.7-8.2 yr); mean duration follow-up = 4.7 years (1.5-10.1 yr). Cochlear implantation. Auditory skills categorized into four levels, temporal bone imaging findings, perioperative complications, time to emergence of speech perception, expressive communication mode. All children imaged with magnetic resonance imaging had cochlear nerve deficiency in at least one ear. Speech awareness threshold improved with the CI compared with aided preoperative in 83% of children, with means of 51.7 dB SAT preoperative and 27.1 dB with the CI (p ≤ 0.002). Overall, four children improved to auditory Level 2 (improved detection), three obtained Level 3 (closed-set speech perception), and three had open-set speech perception with their CIs (Level 4) that was first evident at 3.5, 3.3, and 0.8 years postimplant testing. Two children had minimal or limited improvement. One child with hypoplasia of the cochlear nerve obtained open-set levels. Auditory skills may develop slowly in children with CHARGE syndrome who receive a CI but most can achieve at least improved detection. In our series, half acquired some speech perception ability. Cochlear nerve deficiency is frequent, but should not be a contraindication to implantation.

  19. The relation between auditory-nerve temporal responses and perceptual rate integration in cochlear implants.

    Science.gov (United States)

    Hughes, Michelle L; Baudhuin, Jacquelyn L; Goehring, Jenny L

    2014-10-01

    The purpose of this study was to examine auditory-nerve temporal response properties and their relation to psychophysical threshold for electrical pulse trains of varying rates ("rate integration"). The primary hypothesis was that better rate integration (steeper slope) would be correlated with smaller decrements in ECAP amplitude as a function of stimulation rate (shallower slope of the amplitude-rate function), reflecting a larger percentage of the neural population contributing more synchronously to each pulse in the train. Data were obtained for 26 ears in 23 cochlear-implant recipients. Electrically evoked compound action potential (ECAP) amplitudes were measured in response to each of 21 pulses in a pulse train for the following rates: 900, 1200, 1800, 2400, and 3500 pps. Psychophysical thresholds were obtained using a 3-interval, forced-choice adaptive procedure for 300-ms pulse trains of the same rates as used for the ECAP measures, which formed the rate-integration function. For each electrode, the slope of the psychophysical rate-integration function was compared to the following ECAP measures: (1) slope of the function comparing average normalized ECAP amplitude across pulses versus stimulation rate ("adaptation"), (2) the rate that produced the maximum alternation depth across the pulse train, and (3) rate at which the alternating pattern ceased (stochastic rate). Results showed no significant relations between the slope of the rate-integration function and any of the ECAP measures when data were collapsed across subjects. However, group data showed that both threshold and average ECAP amplitude decreased with increased stimulus rate, and within-subject analyses showed significant positive correlations between psychophysical thresholds and mean ECAP response amplitudes across the pulse train. These data suggest that ECAP temporal response patterns are complex and further study is required to better understand the relative contributions of adaptation

  20. [Endoscopy of the middle ear].

    Science.gov (United States)

    Ayache, Stéphane

    2010-12-20

    The otoscopy is a major point in a daily practice. The otoscope is usually used. In an ENT practice, the microscope is the main instrument but presents limits. The use of rigid endoscopes allows to refine considerably this otoscopy. In ear surgery, the endoscopy of the middle ear for ear chronic diseases has evolved, from an additional tool to the microscope towards an exclusive surgical procedure with its own indications, advantages and limits.

  1. Cochlear Implantation in Patients with Keratitis-Ichthyosis-Deafness Syndrome: A Report of Two Cases

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    Birgul Gumus

    2017-01-01

    Full Text Available Background. Keratitis-ichthyosis-deafness (KID syndrome is a syndrome which presents with hearing loss and visual and keratinization disorders. In such patients, hearing aids cannot be effectively used in the rehabilitation of hearing loss because of the frequent blockage of the external ear canal with epithelial debris and due to dry and tense skin of the external ear canal. Moreover, severe or profound hearing loss also limits the benefits gained from the conventional hearing aids. On the other hand, cochlear implantation is a method that has been used in limited cases in the literature. Case Report. This study presents the results of cochlear implantation applied in our clinic to two children who had been diagnosed with KID. Audiological assessments before and after the cochlear implant operation were performed using pure-tone audiometry, immittance audiometry, and auditory brainstem response (ABR, and the postoperative follow-up was conducted using pure-tone audiometry. Conclusion. Skin problems, visual disturbances, and other additional problems complicate the short-term and long-term rehabilitation after implantation in individuals with KID syndrome. Close monitoring should be exercised due to possible skin complications that may develop during the postoperative period. The families and rehabilitation teams should be warned about the possible visual disturbances and skin complications.

  2. Signal Processing Strategies for Cochlear Implants Using Current Steering

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    Waldo Nogueira

    2009-01-01

    Full Text Available In contemporary cochlear implant systems, the audio signal is decomposed into different frequency bands, each assigned to one electrode. Thus, pitch perception is limited by the number of physical electrodes implanted into the cochlea and by the wide bandwidth assigned to each electrode. The Harmony HiResolution bionic ear (Advanced Bionics LLC, Valencia, CA, USA has the capability of creating virtual spectral channels through simultaneous delivery of current to pairs of adjacent electrodes. By steering the locus of stimulation to sites between the electrodes, additional pitch percepts can be generated. Two new sound processing strategies based on current steering have been designed, SpecRes and SineEx. In a chronic trial, speech intelligibility, pitch perception, and subjective appreciation of sound were compared between the two current steering strategies and standard HiRes strategy in 9 adult Harmony users. There was considerable variability in benefit, and the mean results show similar performance with all three strategies.

  3. Selective attention reduces physiological noise in the external ear canals of humans. I: Auditory attention

    Science.gov (United States)

    Walsh, Kyle P.; Pasanen, Edward G.; McFadden, Dennis

    2014-01-01

    In this study, a nonlinear version of the stimulus-frequency OAE (SFOAE), called the nSFOAE, was used to measure cochlear responses from human subjects while they simultaneously performed behavioral tasks requiring, or not requiring, selective auditory attention. Appended to each stimulus presentation, and included in the calculation of each nSFOAE response, was a 30-ms silent period that was used to estimate the level of the inherent physiological noise in the ear canals of our subjects during each behavioral condition. Physiological-noise magnitudes were higher (noisier) for all subjects in the inattention task, and lower (quieter) in the selective auditory-attention tasks. These noise measures initially were made at the frequency of our nSFOAE probe tone (4.0 kHz), but the same attention effects also were observed across a wide range of frequencies. We attribute the observed differences in physiological-noise magnitudes between the inattention and attention conditions to different levels of efferent activation associated with the differing attentional demands of the behavioral tasks. One hypothesis is that when the attentional demand is relatively great, efferent activation is relatively high, and a decrease in the gain of the cochlear amplifier leads to lower-amplitude cochlear activity, and thus a smaller measure of noise from the ear. PMID:24732069

  4. Pharmacokinetic Properties of Adenosine Amine Congener in Cochlear Perilymph after Systemic Administration

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    Hao Chang

    2017-01-01

    Full Text Available Noise-induced hearing loss (NIHL is a global health problem affecting over 5% of the population worldwide. We have shown previously that acute noise-induced cochlear injury can be ameliorated by administration of drugs acting on adenosine receptors in the inner ear, and a selective A1 adenosine receptor agonist adenosine amine congener (ADAC has emerged as a potentially effective treatment for cochlear injury and resulting hearing loss. This study investigated pharmacokinetic properties of ADAC in rat perilymph after systemic (intravenous administration using a newly developed liquid chromatography-tandem mass spectrometry detection method. The method was developed and validated in accordance with the USA FDA guidelines including accuracy, precision, specificity, and linearity. Perilymph was sampled from the apical turn of the cochlea to prevent contamination with the cerebrospinal fluid. ADAC was detected in cochlear perilymph within two minutes following intravenous administration and remained in perilymph above its minimal effective concentration for at least two hours. The pharmacokinetic pattern of ADAC was significantly altered by exposure to noise, suggesting transient changes in permeability of the blood-labyrinth barrier and/or cochlear blood flow. This study supports ADAC development as a potential clinical otological treatment for acute sensorineural hearing loss caused by exposure to traumatic noise.

  5. Parental mode of communication is essential for speech and language outcomes in cochlear implanted children.

    Science.gov (United States)

    Percy-Smith, Lone; Cayé-Thomasen, Per; Breinegaard, Nina; Jensen, Jørgen Hedegaard

    2010-06-01

    The present study demonstrates a very strong effect of the parental communication mode on the auditory capabilities and speech/language outcome for cochlear implanted children. The children exposed to spoken language had higher odds of scoring high in all tests applied and the findings suggest a very clear benefit of spoken language communication with a cochlear implanted child. The aim of the study was to identify factors associated with speech and language outcomes for cochlear implanted children and also to estimate the effect-related odds ratio for each factor in relation to the children's speech and language performances. Data relate to 155 prelingually deafened children with cochlear implant (CI). A test battery consisting of six different speech and language tests/assessments was used. Seven different factors were considered, i.e. hearing age, implantation age, gender, educational placement, ear of implantation, CI center, and communication mode. Logistic regression models and proportional odds models were used to analyze the relationship between the considered factors and test responses. The communication mode at home proved essential to speech and language outcome, as children exposed to spoken language had markedly better odds of performing well in all tests, compared with children exposed to a mixture of spoken language and sign support, or sign language.

  6. Neural Response Telemetry Thresholds in Patients with Cochlear Nerve Canal Stenosis.

    Science.gov (United States)

    Han, Shuguang; Wang, Line; Zhang, Daoxing; Peng, Kevin

    2015-09-01

    To explore neural response telemetry (NRT) thresholds in patients with stenotic versus normal cochlear nerve canals. Case series with chart review. Tertiary referral center. Thirty pediatric patients with profound sensorineural hearing loss in at least 1 ear and no benefit from amplification underwent computed tomography imaging of the temporal bones. They were divided into 3 groups according to the diameter of the cochlear nerve canal: group A, <1.5 mm; group B, 1.5 to 1.7 mm; group C, 1.8 to 2.1 mm. All patients underwent cochlear implantation with full insertion of all electrodes. NRT was performed both intraoperatively and 6 months postoperatively in all patients; thresholds of electrodes 1, 11, and 22 were compared. Per analysis of variance, intraoperative and 6-month postoperative NRT thresholds were both significantly different among groups A, B, and C at electrodes 1 and 22 but not at electrode 11. On intergroup analysis, group A showed statistically higher thresholds than those of groups B and C; however, no difference was found between groups B and C. Cochlear nerve canal stenosis, defined as a canal diameter <1.5 mm, is associated with significantly increased NRT thresholds, which may play a role in postimplant performance. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.

  7. Age at implantation and auditory memory in cochlear implanted children.

    Science.gov (United States)

    Mikic, B; Miric, D; Nikolic-Mikic, M; Ostojic, S; Asanovic, M

    2014-05-01

    Early cochlear implantation, before the age of 3 years, provides the best outcome regarding listening, speech, cognition an memory due to maximal central nervous system plasticity. Intensive postoperative training improves not only auditory performance and language, but affects auditory memory as well. The aim of this study was to discover if the age at implantation affects auditory memory function in cochlear implanted children. A total of 50 cochlear implanted children aged 4 to 8 years were enrolled in this study: early implanted (1-3y) n = 27 and late implanted (4-6y) n = 23. Two types of memory tests were used: Immediate Verbal Memory Test and Forward and Backward Digit Span Test. Early implanted children performed better on both verbal and numeric tasks of auditory memory. The difference was statistically significant, especially on the complex tasks. Early cochlear implantation, before the age of 3 years, significantly improve auditory memory and contribute to better cognitive and education outcomes.

  8. Reading skills after cochlear implantation

    NARCIS (Netherlands)

    Vermeulen, A.M.

    2007-01-01

    It has frequently been found that profoundly deaf children with conventional hearing aids have difficulties with the comprehension of written text. Cochlear Implants (CIs) were expected to enhance the reading comprehension of these profoundly deaf children because they provide auditory access to

  9. Alterations in cochlear function during induced acute hyperinsulinemia in an animal model Alterações na função coclear durante a indução aguda de hiperinsulinismo em um modelo animal

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    Roberto Dihl Angeli

    2009-10-01

    Full Text Available Hyperinsulinism secondary to peripheral insulin resistance has been described as the most frequent etiologic factor in cochlear and vestibular syndromes. AIM: This experimental study recorded and analyzed evoked auditory potential changes using transtympanic electrocochleography (EcochG during induced acute hyperinsulinism in an animal model. MATERIALS AND METHODS: Six adult male sheep were randomly divided into 2 groups. The animals were submitted to EcochG under general anesthesia, and a peripheral blood sample was collected to measure glycemia and insulinemia. Animals in the intervention group (n=3 received regular human insulin IV (0.1 U/kg. The control group (n=3 received saline solution. Glycemia and insulinemia were measured simultaneously with the recording of evoked potentials at 10-minute intervals during 90 minutes. RESULTS: The intervention group experienced a progressive suppression in action potential amplitude when compared to the control group (p=0.001. CONCLUSION: Data strongly suggest that acute induced hyperinsulinism suppresses cochlear function. Results may be attributed to loss of Na+K+ATPase activity in the stria vascularis, leading to loss of endocochlear potential and subsequent depolarization of cochlear hair cells as well as of neural cells in the auditory portion of cranial nerve VIII.O hiperinsulinismo secundário à resistência periférica à insulina tem sido apontado como o fator etiológico mais frequente de síndromes tanto vestibulares como cocleares. OBJETIVO: Este estudo experimental registrou e analisou as alterações dos potenciais evocados auditivos através da eletrococleografia (ECoG transtimpânica durante o hiperinsulinismo agudo induzido em um modelo animal. MATERIAL E MÉTODO: 6 ovelhas macho adultas foram divididas randomicamente em 2 grupos. Os animais submeteram-se ao exame de ECoG sob anestesia geral, e sangue periférico foi coletado para determinação de glicemia e hiperinsulinemia. Os

  10. A comparative study on efficiency of middle ear pressure equalization techniques in healthy volunteers.

    Science.gov (United States)

    Hidir, Yusuf; Ulus, Sergül; Karahatay, Serdar; Satar, Bulent

    2011-08-01

    To compare success rates of middle ear inflation device (Ear Popper (©)), Valsalva maneuver and Toynbee maneuver in middle ear pressure equalization in healthy adults. Adult volunteers with otoscopically healthy ears were enrolled to the study. In a prospective setting, 60 ears of 35 volunteers were divided into two groups according to eustachian tube (ET) functions tested using the nine step inflation deflation test. Group A: good eustachian tube function at nine step inflation deflation test (30 ears), Group B: possible dysfunction of the ET at nine step inflation deflation test (30 ears). All the volunteers performed Valsalva maneuver, Toynbee maneuver and Ear Popper(©) application, respectively. The efficiencies of all the three techniques were statistically compared first overall, then paired-wise between the two groups. There was no statistical difference in success rates of middle ear pressure equalization techniques in 60 ears, regardless of ET function results (Valsalva and Toynbee maneuvers 51.7% effective, Ear Popper(©) 43.3% effective). There was also no statistical difference among the middle ear pressure shifts obtained by these three techniques. In almost half of the subjects in whom at least one technique was unsuccessful, the other two was effective. When the groups were separately compared; there was no significant difference between Valsalva and Toynbee maneuvers, whereas Ear Popper(©) was found more effective in Group A (56.7% vs. 30%, p=0.037). No statistical difference in equalization of the middle ear pressure was found among Valsalva maneuvers, Toynbee maneuvers and Ear Popper(©) in healthy adults under physiological conditions. Using alternative techniques may improve the success individually when a technique fails. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  11. THE EARLY INTERVENTION TENDENCY OF CHINESE CHILDREN WITH COCHLEAR IMPLANTS

    OpenAIRE

    Wu, Jiaojiao; Xie, Yuhan

    2016-01-01

    From the change of adult unilateral cochlear implantation into young children even under the age of six implant cochlear, sequential bilateral cochlear implantation, which benefit by early hearing screening and technological development of cochlear implants. It is a worldwide trend that simultaneous bilateral cochlear implantation for hearing impaired children under the age of three. Cochlear implants bring changes of education opportunities and choices for children with hearing impairment. F...

  12. Spatial hearing of normally hearing and cochlear implanted children.

    Science.gov (United States)

    Murphy, John; Summerfield, A Quentin; O'Donoghue, Gerard M; Moore, David R

    2011-04-01

    Spatial hearing uses both monaural and binaural mechanisms that require sensitive hearing for normal function. Deaf children using either bilateral (BCI) or unilateral (UCI) cochlear implants would thus be expected to have poorer spatial hearing than normally hearing (NH) children. However, the relationship between spatial hearing in these various listener groups has not previously been extensively tested under ecologically valid conditions using a homogeneous group of children who are UCI users. We predicted that NH listeners would outperform BCI listeners who would, in turn, outperform UCI listeners. We tested two methods of spatial hearing to provide norms for NH and UCI using children and preliminary data for BCI users. NH children (n=40) were age matched (6-15 years) to UCI (n=12) and BCI (n=6) listeners. Testing used a horizontal ring of loudspeakers within a booth in a hospital outpatient clinic. In a 'lateral release' task, single nouns were presented frontally, and masking noises were presented frontally, or 90° left or right. In a 'localization' task, allowing head movements, nouns were presented from loudspeakers separated by 30°, 60° or 120° about the midline. Normally hearing children improved with age in speech detection in noise, but not in quiet or in lateral release. Implant users performed more poorly on all tasks. For frontal signals and noise, UCI and BCI listeners did not differ. For lateral noise, BCI listeners performed better on both sides (within ~2 dB of NH), whereas UCI listeners benefited only when the noise was opposite the unimplanted ear. Both the BCI and, surprisingly, the UCI listeners performed better than chance at all loudspeaker separations on the ecologically valid, localization task. However, the BCI listeners performed about twice as well and, in two cases, approached the performance of NH children. Children using either UCI or BCI have useful spatial hearing. BCI listeners gain benefits on both sides, and localize better

  13. Persistent Thalamic Sound Processing Despite Profound Cochlear Denervation

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    Anna R. Chambers

    2016-08-01

    Full Text Available Neurons at higher stages of sensory processing can partially compensate for a sudden drop in input from the periphery through a homeostatic plasticity process that increases the gain on weak afferent inputs. Even after a profound unilateral auditory neuropathy where > 95% of synapses between auditory nerve fibers and inner hair cells have been eliminated with ouabain, central gain can restore the cortical processing and perceptual detection of basic sounds delivered to the denervated ear. In this model of profound auditory neuropathy, cortical processing and perception recover despite the absence of an auditory brainstem response (ABR or brainstem acoustic reflexes, and only a partial recovery of sound processing at the level of the inferior colliculus (IC, an auditory midbrain nucleus. In this study, we induced a profound cochlear neuropathy with ouabain and asked whether central gain enabled a compensatory plasticity in the auditory thalamus comparable to the full recovery of function previously observed in the auditory cortex (ACtx, the partial recovery observed in the IC, or something different entirely. Unilateral ouabain treatment in adult mice effectively eliminated the ABR, yet robust sound-evoked activity persisted in a minority of units recorded from the contralateral medial geniculate body (MGB of awake mice. Sound-driven MGB units could decode moderate and high-intensity sounds with accuracies comparable to sham-treated control mice, but low-intensity classification was near chance. Pure tone receptive fields and synchronization to broadband pulse trains also persisted, albeit with significantly reduced quality and precision, respectively. MGB decoding of temporally modulated pulse trains and speech tokens were both greatly impaired in ouabain-treated mice. Taken together, the absence of an ABR belied a persistent auditory processing at the level of the MGB that was likely enabled through increased central gain. Compensatory

  14. What Is an Ear Infection?

    Science.gov (United States)

    ... your ear with a special flashlight called an otoscope (say: OH-te-skope). With the otoscope, the doctor can see your eardrum , the thin ... and middle ear. The doctor may use the otoscope to blow a little puff of air in ...

  15. Endoscopic Ear Surgery: Critical Review of Anatomy and Physiology of Normal and Reconstructive Middle Ear.

    Science.gov (United States)

    Udagatti, Vithal D; Dinesh Kumar, Rajendran

    2016-06-01

    Middle ear anatomy is complex hence it is difficult to study the microscopic vibration of tympanic membrane and ossicles. The basic research has been done in few centres. Our experience is based on clinical data. The lack of quantitative understanding of structural and functional relationship in the mechanical response of the normal and reconstructed middle ear is major factor in poor hearing results after surgery (Merchant et al. in J Laryngol Otol 112:715-731, 1998). The vibration pattern of tympanic membrane changes with different frequencies. It depends upon shape, position and tension of tympanic membrane. Sometimes reconstructed tympanic membrane loses its shape and tension and thus its vibratory response (Pusalkar and Steinbach in Transplants and implants in otology II, 1992). Then what should be the shape, position, tension of the tympanic membrane and the ossicles. In order to have a serviceable hearing, dry and safe ear, there is a necessity of answering all these queries by us.

  16. Adult human nasal mesenchymal-like stem cells restore cochlear spiral ganglion neurons after experimental lesion.

    Science.gov (United States)

    Bas, Esperanza; Van De Water, Thomas R; Lumbreras, Vicente; Rajguru, Suhrud; Goss, Garrett; Hare, Joshua M; Goldstein, Bradley J

    2014-03-01

    A loss of sensory hair cells or spiral ganglion neurons from the inner ear causes deafness, affecting millions of people. Currently, there is no effective therapy to repair the inner ear sensory structures in humans. Cochlear implantation can restore input, but only if auditory neurons remain intact. Efforts to develop stem cell-based treatments for deafness have demonstrated progress, most notably utilizing embryonic-derived cells. In an effort to bypass limitations of embryonic or induced pluripotent stem cells that may impede the translation to clinical applications, we sought to utilize an alternative cell source. Here, we show that adult human mesenchymal-like stem cells (MSCs) obtained from nasal tissue can repair spiral ganglion loss in experimentally lesioned cochlear cultures from neonatal rats. Stem cells engraft into gentamicin-lesioned organotypic cultures and orchestrate the restoration of the spiral ganglion neuronal population, involving both direct neuronal differentiation and secondary effects on endogenous cells. As a physiologic assay, nasal MSC-derived cells engrafted into lesioned spiral ganglia demonstrate responses to infrared laser stimulus that are consistent with those typical of excitable cells. The addition of a pharmacologic activator of the canonical Wnt/β-catenin pathway concurrent with stem cell treatment promoted robust neuronal differentiation. The availability of an effective adult autologous cell source for inner ear tissue repair should contribute to efforts to translate cell-based strategies to the clinic.

  17. Notch signaling and the developing inner ear.

    Science.gov (United States)

    Murata, Junko; Ikeda, Katsuhisa; Okano, Hideyuki

    2012-01-01

    Sensory hair cells (HCs) and their associated nonsensory supporting cells (SCs) exhibit a typical mosaic pattern in each of the sensory patches in the inner ear. Notch signaling has been considered to conduct the formation of this mosaic pattern through one of its famous functions, known as 'lateral inhibition'. The two Notch ligands Delta-like1 and Jagged2 are believed to act synergistically at the stage of cell diversification in mammals. In addition, many current studies suggest that Notch signaling has another inductive, but not inhibiting, role in the determination of the prosensory region, which precedes the cell diversification of HCs and SCs and Jagged1 is thought to be an essential ligand in this process. Earlier in ear development, the first cell fate determination begins with the delamination of the neuroblasts from the otic epithelium. The delaminated neuroblasts migrate and coalesce to form cochleovestibular ganglion. Notch signaling pathway is thought to function during the delamination through its lateral inhibitory mechanism. Recently, many experiments examining Notch-related gene expression patterns and direct functional analyses of genes have revealed multiple important functions of Notch in inner ear development. Here, we survey a series of studies and discuss the issues that remain to be elucidated in the future.

  18. Stimulation from Cochlear Implant Electrodes Assists with Recovery from Asymmetric Perceptual Tilt: Evidence from the Subjective Visual Vertical Test

    Directory of Open Access Journals (Sweden)

    Joshua J. Gnanasegaram

    2016-09-01

    Full Text Available Vestibular end organ impairment is highly prevalent in children who have sensorineural hearing loss (SNHL rehabilitated with cochlear implants (CIs. As a result, spatial perception is likely to be impacted in this population. Of particular interest is the perception of visual vertical because it reflects a perceptual tilt in the roll axis and is sensitive to an imbalance in otolith function. The objectives of the present study were thus to identify abnormalities in perception of the vertical plane in children with SNHL and determine whether such abnormalities could be resolved with stimulation from the CI. Participants included 53 children (15.2±4.0 years of age with SNHL and vestibular loss, confirmed with vestibular evoked myogenic potential testing. Testing protocol was validated in a sample of 9 young adults with normal hearing (28.8±7.7 years. Perception of visual vertical was assessed using the static Subjective Visual Vertical (SVV test performed with and without stimulation in the participants with cochleovestibular loss. Trains of electrical pulses were delivered by an electrode in the left and/or right ear. Asymmetric spatial orientation deficits were found in nearly half of the participants with CIs (24/53 [45%]. The abnormal perception in this cohort was exacerbated by visual tilts in the direction of their deficit. Electric pulse trains delivered using the CI shifted this abnormal perception towards centre (i.e., normal [p = 0.007]. Importantly, this benefit was realized regardless of which ear was stimulated. These results suggest a role for CI stimulation beyond the auditory system, in particular, for improving vestibular/balance function.

  19. Inner ear tissue remodeling and ion homeostasis gene alteration in murine chronic otitis media.

    Science.gov (United States)

    MacArthur, Carol J; Hausman, Fran; Kempton, J Beth; Sautter, Nathan; Trune, Dennis R

    2013-02-01

    Studies were designed to ascertain the impact of chronic middle ear infection on the numerous ion and water channels, transporters, and tissue remodeling genes in the inner and middle ear. Permanent sensorineural hearing loss is a significant problem resulting from chronic middle ear disease, although the inner ear processes involved are poorly defined. Maintaining a balanced ionic composition of endolymph in the inner ear is crucial for hearing; thus, it was hypothesized that this may be at risk with inflammation. Inner and middle ear RNA collected separately from 6-month-old C3H/HeJ mice with prolonged middle ear disease were subjected to qRT-PCR for 8 common inflammatory cytokine genes, 24 genes for channels controlling ion (sodium, potassium, and chloride) and water (aquaporin) transport, tight junction claudins, and gap junction connexins, and 32 tissue remodeling genes. Uninfected Balb/c mice were used as controls. Significant increase in inner ear inflammatory and ion homeostasis (claudin, aquaporin, and gap junction) gene expression, and both upregulation and downregulation of tissue remodeling gene expression occurred. Alteration in middle ear ion homeostasis and tissue remodeling gene expression was noted in the setting of uniform upregulation of cytokine genes. Chronic inflammatory middle ear disease can impact inner ear ion and water transport functions and induce tissue remodeling. Recognizing these inner ear mechanisms at risk may identify potential therapeutic targets to maintain hearing during prolonged otitis media.

  20. An ultra-low-power programmable analog bionic ear processor.

    Science.gov (United States)

    Sarpeshkar, Rahul; Salthouse, Christopher; Sit, Ji-Jon; Baker, Michael W; Zhak, Serhii M; Lu, Timothy K T; Turicchia, Lorenzo; Balster, Stephanie

    2005-04-01

    We report a programmable analog bionic ear (cochlear implant) processor in a 1.5-microm BiCMOS technology with a power consumption of 211 microW and 77-dB dynamic range of operation. The 9.58 mm x 9.23 mm processor chip runs on a 2.8 V supply and has a power consumption that is lower than state-of-the-art analog-to-digital (A/D)-then-DSP designs by a factor of 25. It is suitable for use in fully implanted cochlear-implant systems of the future which require decades of operation on a 100-mAh rechargeable battery with a finite number of charge-discharge cycles. It may also be used as an ultra-low-power spectrum-analysis front end in portable speech-recognition systems. The power consumption of the processor includes the 100 microW power consumption of a JFET-buffered electret microphone and an associated on-chip microphone front end. An automatic gain control circuit compresses the 77-dB input dynamic range into a narrower internal dynamic range (IDR) of 57 dB at which each of the 16 spectral channels of the processor operate. The output bits of the processor are scanned and reported off chip in a format suitable for continuous-interleaved-sampling stimulation of electrodes. Power-supply-immune biasing circuits ensure robust operation of the processor in the high-RF-noise environment typical of cochlear implant systems.

  1. Comparative study between unilateral and bilateral cochlear implantation in children of 1 and 2 years of age.

    Science.gov (United States)

    Escorihuela García, Vicente; Pitarch Ribas, María Ignacia; Llópez Carratalá, Ignacio; Latorre Monteagudo, Emilia; Morant Ventura, Antonio; Marco Algarra, Jaime

    2016-01-01

    The studies that have evaluated the effectiveness of bilateral cochlear implantation in children suggest an improvement in hearing about sound localization and speech discrimination. In this paper we show the differences in audio-linguistic achievements with early bilateral cochlear implantation versus unilateral, and differences between simultaneous and sequential bilateral implantation. We present 88 children with bilateral profound sensorineural hearing loss, treated with bilateral cochlear implantation in 32 cases and unilateral in 56 cases, during the first 12 months (27 children) of life and between 12 and 24 months (61 children). We conducted a statistical comparison of both groups in the audiometry, IT-Mais, Nottingham, LittlEars scales and verbal tests. No significant differences in hearing thresholds and questionnaires between unilateral and bilateral implantation were detected in either the first or second year. Verbal tests do show statistically significant differences: children with bilateral cochlear implant obtain 100% recognition of disyllabic and phrases within 2-3 years after implantation whilst children with one implant do not obtain those results at 5 years after surgery. No differences between simultaneous and sequential bilateral implantation were detected. We emphasize the importance of ensuring good early audiological screening, to carry out an early and bilateral cochlear implantation with the consequent development of audio-language skills similar to normal hearing children. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

  2. Progression of Unilateral Hearing Loss in Children With and Without Ipsilateral Cochlear Nerve Canal Stenosis: A Hazard Analysis.

    Science.gov (United States)

    Purcell, Patricia L; Shinn, Justin R; Coggeshall, Scott S; Phillips, Grace; Paladin, Angelisa; Sie, Kathleen C Y; Horn, David L

    2017-07-01

    To investigate the risk of hearing loss progression in each ear among children with unilateral hearing loss associated with ipsilateral bony cochlear nerve canal (BCNC) stenosis. Tertiary pediatric referral center. Children diagnosed with unilateral hearing loss who had undergone temporal bone computed tomography imaging and had at least 6 months of follow-up audiometric testing were identified from a prospective audiological database. Two pediatric radiologists blinded to affected ear evaluated imaging for temporal bone anomalies and measured bony cochlear canal width independently. All available audiograms were reviewed, and air conduction thresholds were documented. Progression of hearing loss was defined by a 10 dB increase in air conduction pure-tone average. One hundred twenty eight children met inclusion criteria. Of these, 54 (42%) had a temporal bone anomaly, and 22 (17%) had ipsilateral BCNC stenosis. At 12 months, rates of progression in the ipsilateral ear were as follows: 12% among those without a temporal bone anomaly, 13% among those with a temporal bone anomaly, and 17% among those with BCNC stenosis. Children with BCNC stenosis had a significantly greater risk of progression in their ipsilateral ear compared with children with no stenosis: hazard ratio (HR) 2.17, 95% confidence interval (CI) (1.01, 4.66), p value 0.046. When we compared children with BCNC stenosis to those with normal temporal bone imaging, we found that the children with stenosis had nearly two times greater risk estimate for progression, but this difference did not reach significance, HR 1.9, CI (0.8, 4.3), p = 0.1. No children with BCNC stenosis developed hearing loss in their contralateral year by 12 months of follow-up. Children with bony cochlear nerve canal stenosis may be at increased risk for progression in their ipsilateral ear. Audiometric and medical follow-up for these children should be considered.

  3. Association of microRNA 146 with middle ear hyperplasia in pediatric otitis media.

    Science.gov (United States)

    Samuels, Tina L; Yan, Justin; Khampang, Pawjai; MacKinnon, Alexander; Hong, Wenzhou; Johnston, Nikki; Kerschner, Joseph E

    2016-09-01

    Toll-like receptor signaling activated by bacterial otitis media pathogens in the middle ear has been shown to play a key role in OM susceptibility, pathogenesis and recovery. Recent studies implicate microRNA 146 (miR-146) in regulation of inflammation via negative feedback of toll-like receptor signaling (TLR) in a wide variety of tissues, however its involvement in otitis media is unknown. Human middle ear epithelial cells were stimulated with proinflammatory cytokines, interleukin 1 beta or tumor necrosis factor alpha, for two to twenty-four hours. Middle ear biopsies were collected from children with otitis media with effusion (n = 20), recurrent otitis media (n = 9), and control subjects undergoing cochlear implantation (n = 10). miR-146a, miR-146b expression was assayed by quantitative PCR (qPCR). Expression of miR-146 targets involved in TLR signaling, IRAK1 and TRAF6, was assayed by qPCR in middle ear biopsies. Middle ear biopsies were cryosectioned and epithelial thickness measured by a certified pathologist. Proinflammatory cytokines induced expression of miR-146 in middle ear epithelial cells in vitro. Middle ear miR-146a and miR-146b expression was elevated in otitis media patients relative to control subjects and correlated with middle ear epithelial thickness. A trend towards inverse correlation was observed between miR-146 and TRAF6 expression in the clinical population. This report is the first to assess miRNA expression in a clinical population with OM. Findings herein suggest miR-146 may play a role in OM. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  4. Educational performance of pediatric cochlear implant recipients in mainstream classes.

    Science.gov (United States)

    Mukari, Siti Z; Ling, Lai N; Ghani, Hanizam A

    2007-02-01

    The present study documents the school performance of 20 pediatric cochlear implant recipients who attended mainstream classes and compares their educational performance with their normally hearing peers. All 20 school-aged children who underwent cochlear implantation at the Universiti Kebangsaan Malaysia cochlear implant programme participated in this study. Three measures were employed to assess the school performance. First, using the SIFTER teacher-rating scale, the second measure was the child's examination results, and the third was the child's standing compared to his/her peers in language subject, mathematics, and the overall academic performance during the end of semester examinations. The SIFTER rating scale indicated that only 11.8% of the children were identified as not educationally at risk, 17.6% passed four of the SIFTER subtests, whereas the other 71.6% failed in at least two of the subtests on SIFTER. The highest pass rate was obtained in behavior subtest (76.5%), followed by classroom participation (70.6%), attention (58.8%), academic (47.1%), and communication (11.8%). On the educational performance, the cochlear implant recipients performed significantly better in mathematics (mean scores 62.67%; S.D. 22.24) than in language (mean scores 49.96%, S.D. 25.88) (p75th percentile), 18.75% had average performance (25-75th percentile), and another 56.25% performed at below average (mainstream classes varies. Although 43.75% of them thrive well in a full-time mainstream setting, a significant percentage of them (56.25%) performed at below the average level. These findings reemphasize that although a cochlear implant has successfully provided deaf children with a good hearing potential, the majority of its recipients still require additional educational supports in order to function well in the mainstream educational setting.

  5. Cochlear implant revision surgeries in children.

    Science.gov (United States)

    Amaral, Maria Stella Arantes do; Reis, Ana Cláudia Mirândola B; Massuda, Eduardo T; Hyppolito, Miguel Angelo

    2018-02-16

    The surgery during which the cochlear implant internal device is implanted is not entirely free of risks and may produce problems that will require revision surgeries. To verify the indications for cochlear implantation revision surgery for the cochlear implant internal device, its effectiveness and its correlation with certain variables related to language and hearing. A retrospective study of patients under 18 years submitted to cochlear implant Surgery from 2004 to 2015 in a public hospital in Brazil. Data collected were: age at the time of implantation, gender, etiology of the hearing loss, audiological and oral language characteristics of each patient before and after Cochlear Implant surgery and any need for surgical revision and the reason for it. Two hundred and sixty-five surgeries were performed in 236 patients. Eight patients received a bilateral cochlear implant and 10 patients required revision surgery. Thirty-two surgeries were necessary for these 10 children (1 bilateral cochlear implant), of which 21 were revision surgeries. In 2 children, cochlear implant removal was necessary, without reimplantation, one with cochlear malformation due to incomplete partition type I and another due to trauma. With respect to the cause for revision surgery, of the 8 children who were successfully reimplanted, four had cochlear calcification following meningitis, one followed trauma, one exhibited a facial nerve malformation, one experienced a failure of the cochlear implant internal device and one revision surgery was necessary because the electrode was twisted. The incidence of the cochlear implant revision surgery was 4.23%. The period following the revision surgeries revealed an improvement in the subject's hearing and language performance, indicating that these surgeries are valid in most cases. Copyright © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  6. Unilateral and bilateral cochlear implants and the implant-plus-hearing-aid profile: comparing self-assessed and measured abilities.

    Science.gov (United States)

    Noble, William; Tyler, Richard; Dunn, Camille; Bhullar, Navjot

    2008-08-01

    Patients fitted with one (CI) versus two (CI+CI) cochlear implants, and those fitted with one implant who retain a hearing aid in the non-implanted ear (CI+HA), were compared using the speech, spatial, and qualities of hearing scale (SSQ) (Gatehouse & Noble, 2004). The CI+CI profile yielded significantly higher ability ratings than the CI profile in the spatial hearing domain, and on most aspects of other qualities of hearing (segregation, naturalness, and listening effort). A subset of patients completed the SSQ prior to implantation, and the CI+CI profile showed consistently greater improvement than the CI profile across all domains. Patients in the CI+HA group self-rated no differently from the CI group, post-implant. Measured speech perception and localization performance showed some parallels with the self-rating outcomes. Overall, a unilateral CI provided significant benefit across most hearing functions reflected in the SSQ. Bilateral implantation offered further benefit across a substantial range of those functions.

  7. Ear Structures of the Naked Mole-Rat, Heterocephalus glaber, and Its Relatives (Rodentia: Bathyergidae.

    Directory of Open Access Journals (Sweden)

    Matthew J Mason

    Full Text Available Although increasingly popular as a laboratory species, very little is known about the peripheral auditory system of the naked mole-rat, Heterocephalus glaber. In this study, middle and inner ears of naked mole-rats of a range of ages were examined using micro-computed tomography and dissection. The ears of five other bathyergid species (Bathyergus suillus, Cryptomys hottentotus, Fukomys micklemi, Georychus capensis and Heliophobius argenteocinereus were examined for comparative purposes. The middle ears of bathyergids show features commonly found in other members of the Ctenohystrica rodent clade, including a fused malleus and incus, a synovial stapedio-vestibular articulation and the loss of the stapedius muscle. Heterocephalus deviates morphologically from the other bathyergids examined in that it has a more complex mastoid cavity structure, poorly-ossified processes of the malleus and incus, a 'columelliform' stapes and fewer cochlear turns. Bathyergids have semicircular canals with unusually wide diameters relative to their radii of curvature. How the lateral semicircular canal reaches the vestibule differs between species. Heterocephalus has much more limited high-frequency hearing than would be predicted from its small ear structures. The spongy bone forming its ossicular processes, the weak incudo-stapedial articulation, the columelliform stapes and (compared to other bathyergids reduced cochlear coiling are all potentially degenerate features which might reflect a lack of selective pressure on its peripheral auditory system. Substantial intraspecific differences were found in certain middle and inner ear structures, which might also result from relaxed selective pressures. However, such interpretations must be treated with caution in the absence of experimental evidence.

  8. Ear Structures of the Naked Mole-Rat, Heterocephalus glaber, and Its Relatives (Rodentia: Bathyergidae).

    Science.gov (United States)

    Mason, Matthew J; Cornwall, Hannah L; Smith, Ewan St J

    2016-01-01

    Although increasingly popular as a laboratory species, very little is known about the peripheral auditory system of the naked mole-rat, Heterocephalus glaber. In this study, middle and inner ears of naked mole-rats of a range of ages were examined using micro-computed tomography and dissection. The ears of five other bathyergid species (Bathyergus suillus, Cryptomys hottentotus, Fukomys micklemi, Georychus capensis and Heliophobius argenteocinereus) were examined for comparative purposes. The middle ears of bathyergids show features commonly found in other members of the Ctenohystrica rodent clade, including a fused malleus and incus, a synovial stapedio-vestibular articulation and the loss of the stapedius muscle. Heterocephalus deviates morphologically from the other bathyergids examined in that it has a more complex mastoid cavity structure, poorly-ossified processes of the malleus and incus, a 'columelliform' stapes and fewer cochlear turns. Bathyergids have semicircular canals with unusually wide diameters relative to their radii of curvature. How the lateral semicircular canal reaches the vestibule differs between species. Heterocephalus has much more limited high-frequency hearing than would be predicted from its small ear structures. The spongy bone forming its ossicular processes, the weak incudo-stapedial articulation, the columelliform stapes and (compared to other bathyergids) reduced cochlear coiling are all potentially degenerate features which might reflect a lack of selective pressure on its peripheral auditory system. Substantial intraspecific differences were found in certain middle and inner ear structures, which might also result from relaxed selective pressures. However, such interpretations must be treated with caution in the absence of experimental evidence.

  9. The Sound Quality of Cochlear Implants: Studies With Single-sided Deaf Patients.

    Science.gov (United States)

    Dorman, Michael F; Natale, Sarah Cook; Butts, Austin M; Zeitler, Daniel M; Carlson, Matthew L

    2017-09-01

    The goal of the present study was to assess the sound quality of a cochlear implant for single-sided deaf (SSD) patients fit with a cochlear implant (CI). One of the fundamental, unanswered questions in CI research is "what does an implant sound like?" Conventional CI patients must use the memory of a clean signal, often decades old, to judge the sound quality of their CIs. In contrast, SSD-CI patients can rate the similarity of a clean signal presented to the CI ear and candidate, CI-like signals presented to the ear with normal hearing. For Experiment 1 four types of stimuli were created for presentation to the normal hearing ear: noise vocoded signals, sine vocoded signals, frequency shifted, sine vocoded signals and band-pass filtered, natural speech signals. Listeners rated the similarity of these signals to unmodified signals sent to the CI on a scale of 0 to 10 with 10 being a complete match to the CI signal. For Experiment 2 multitrack signal mixing was used to create natural speech signals that varied along multiple dimensions. In Experiment 1 for eight adult SSD-CI listeners, the best median similarity rating to the sound of the CI for noise vocoded signals was 1.9; for sine vocoded signals 2.9; for frequency upshifted signals, 1.9; and for band pass filtered signals, 5.5. In Experiment 2 for three young listeners, combinations of band pass filtering and spectral smearing lead to ratings of 10. The sound quality of noise and sine vocoders does not generally correspond to the sound quality of cochlear implants fit to SSD patients. Our preliminary conclusion is that natural speech signals that have been muffled to one degree or another by band pass filtering and/or spectral smearing provide a close, but incomplete, match to CI sound quality for some patients.

  10. The inferior cochlear vein: surgical aspects in cochlear implantation.

    Science.gov (United States)

    Guo, Rui; Zhang, HongLei; Chen, Wei; Zhu, XiaoQuan; Liu, Wei; Rask-Andersen, Helge

    2016-02-01

    The patency of the inferior cochlear vein (ICV) may be challenged in cochlear implantation (CI) due to its location near the round window (RW). This may be essential to consider during selection of different trajectories for electrode insertion aiming at preserving residual hearing. Venous blood from the human cochlea is drained through the ICV. The vein also drains blood from the modiolus containing the spiral ganglion neurons. Surgical interference with this vein could cause neural damage influencing CI outcome. We analyzed the topographical relationship between the RW and ICV bony channel and cochlear aqueduct (CA) from a surgical standpoint. Archival human temporal bones were further microdissected to visualize the CA and its accessory canals (AC1 and AC2). This was combined with examinations of plastic and silicone molds of the human labyrinth. Metric analyses were made using photo stereomicroscopy documenting the proximal portion of the AC1, the internal aperture of the CA and the RW. The mean distance between the AC1 and the anterior rim of the RW was 0.81 mm in bone specimens and 0.67 mm assessed in corrosion casts. The AC1 runs from the floor of the scala tympani through the otic capsule passing parallel to the CA to the posterior cranial fossa. The mean distance between the CA and AC1 canal was 0.31 and 0.25 mm, respectively.

  11. Human ear recognition by computer

    CERN Document Server

    Bhanu, Bir; Chen, Hui

    2010-01-01

    Biometrics deals with recognition of individuals based on their physiological or behavioral characteristics. The human ear is a new feature in biometrics that has several merits over the more common face, fingerprint and iris biometrics. Unlike the fingerprint and iris, it can be easily captured from a distance without a fully cooperative subject, although sometimes it may be hidden with hair, scarf and jewellery. Also, unlike a face, the ear is a relatively stable structure that does not change much with the age and facial expressions. ""Human Ear Recognition by Computer"" is the first book o

  12. Activation of NLRP3 inflammasome in human middle ear cholesteatoma and chronic otitis media.

    Science.gov (United States)

    Kariya, Shin; Okano, Mitsuhiro; Zhao, Pengfei; Kataoka, Yuko; Yoshinobu, Junko; Maeda, Yukihide; Ishihara, Hisashi; Higaki, Takaya; Nishizaki, Kazunori

    2016-01-01

    The nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome plays an important role in the pathogenesis of middle ear diseases. Modulation of inflammasome-mediated inflammation may be a novel therapeutic strategy for cholesteatoma and chronic otitis media. NLRP3 inflammasome is a critical molecule mediating interleukin (IL)-1β responses. However, the expression of NLRP3 in the pathogenesis of cholesteatoma and chronic otitis media has not been fully examined. This study sought to assess the expression of NLRP3, ASC (apoptosis-associated speck-like protein containing a caspase recruitment domain and a pyrin domain), and caspase-1 in middle ear tissues in patients with cholesteatoma or chronic otitis media. Middle ear tissue samples were obtained from patients with cholesteatoma or chronic otitis media. Control middle ear samples were collected during cochlear implant surgery of patients without middle ear inflammation. The expression of NLRP3, ASC, and caspase-1 were examined by reverse transcription polymerase chain reaction (RT-PCR) assay and immunohistochemical study. The levels of mRNA of NLRP3, ASC, and caspase-1 were significantly elevated in cholesteatoma and chronic otitis media as compared with that of normal controls. The proteins of NLRP3, ASC, and caspase-1 were observed in infiltrating inflammatory cells in cholesteatoma and chronic otitis media.

  13. Lumped parametric model of the human ear for sound transmission.

    Science.gov (United States)

    Feng, Bin; Gan, Rong Z

    2004-09-01

    A lumped parametric model of the human auditoria peripherals consisting of six masses suspended with six springs and ten dashpots was proposed. This model will provide the quantitative basis for the construction of a physical model of the human middle ear. The lumped model parameters were first identified using published anatomical data, and then determined through a parameter optimization process. The transfer function of the middle ear obtained from human temporal bone experiments with laser Doppler interferometers was used for creating the target function during the optimization process. It was found that, among 14 spring and dashpot parameters, there were five parameters which had pronounced effects on the dynamic behaviors of the model. The detailed discussion on the sensitivity of those parameters was provided with appropriate applications for sound transmission in the ear. We expect that the methods for characterizing the lumped model of the human ear and the model parameters will be useful for theoretical modeling of the ear function and construction of the ear physical model.

  14. Modeling Analysis of Biomechanical Changes of Middle Ear and Cochlea in Otitis Media

    Science.gov (United States)

    Gan, Rong Z.; Zhang, Xiangming; Guan, Xiying

    2011-11-01

    A comprehensive finite element (FE) model of the human ear including the ear canal, middle ear, and spiral cochlea was developed using histological sections of human temporal bone. The cochlea was modeled with three chambers separated by the basilar membrane and Reissner's membrane and filled with perilymphatic fluid. The viscoelastic material behavior was applied to middle ear soft tissues based on dynamic measurements of tissues in our lab. The model was validated using the experimental data obtained in human temporal bones and then used to simulate various stages of otitis media (OM) including the changes of morphology, mechanical properties, pressure, and fluid level in the middle ear. Function alterations of the middle ear and cochlea in OM were derived from the model and compared with the measurements from temporal bones. This study indicates that OM can be simulated in the FE model to predict the hearing loss induced by biomechanical changes of the middle ear and cochlea.

  15. Reducing the impact of wind noise on cochlear implant processors with two microphones.

    Science.gov (United States)

    Kokkinakis, Kostas; Cox, Casey

    2014-05-01

    Behind-the-ear (BTE) processors of cochlear implant (CI) devices offer little to almost no protection from wind noise in most incidence angles. To assess speech intelligibility, eight CI recipients were tested in 3 and 9 m/s wind. Results indicated that speech intelligibility decreased substantially when the wind velocity, and in turn the wind sound pressure level, increased. A two-microphone wind noise suppression strategy was developed. Scores obtained with this strategy indicated substantial gains in speech intelligibility over other conventional noise reduction strategies tested.

  16. Effects of electrode deactivation on speech recognition in multichannel cochlear implant recipients.

    Science.gov (United States)

    Schvartz-Leyzac, Kara C; Zwolan, Teresa A; Pfingst, Bryan E

    2017-11-01

    The objective of the current study is to evaluate how speech recognition performance is affected by the number of active electrodes that are turned off in multichannel cochlear implants. Several recent studies have demonstrated positive effects of deactivating stimulation sites based on an objective measure in cochlear implant processing strategies. Previous studies using an analysis of variance have shown that, on average, cochlear implant listeners' performance does not improve beyond eight active electrodes. We hypothesized that using a generalized linear mixed model would allow for better examination of this question. Seven peri- and post-lingual adult cochlear implant users (eight ears) were tested on speech recognition tasks using experimental MAPs which contained either 8, 12, 16 or 20 active electrodes. Speech recognition tests included CUNY sentences in speech-shaped noise, TIMIT sentences in quiet as well as vowel (CVC) and consonant (CV) stimuli presented in quiet and in signal-to-noise ratios of 0 and +10 dB. The speech recognition threshold in noise (dB SNR) significantly worsened by approximately 2 dB on average as the number of active electrodes was decreased from 20 to 8. Likewise, sentence recognition scores in quiet significantly decreased by an average of approximately 12%. Cochlear implant recipients can utilize and benefit from using more than eight spectral channels when listening to complex sentences or sentences in background noise. The results of the current study suggest a conservative approach for turning off stimulation sites is best when using site-selection procedures.

  17. Electrophysiological evidence for altered visual, but not auditory, selective attention in adolescent cochlear implant users.

    Science.gov (United States)

    Harris, Jill; Kamke, Marc R

    2014-11-01

    Selective attention fundamentally alters sensory perception, but little is known about the functioning of attention in individuals who use a cochlear implant. This study aimed to investigate visual and auditory attention in adolescent cochlear implant users. Event related potentials were used to investigate the influence of attention on visual and auditory evoked potentials in six cochlear implant users and age-matched normally-hearing children. Participants were presented with streams of alternating visual and auditory stimuli in an oddball paradigm: each modality contained frequently presented 'standard' and infrequent 'deviant' stimuli. Across different blocks attention was directed to either the visual or auditory modality. For the visual stimuli attention boosted the early N1 potential, but this effect was larger for cochlear implant users. Attention was also associated with a later P3 component for the visual deviant stimulus, but there was no difference between groups in the later attention effects. For the auditory stimuli, attention was associated with a decrease in N1 latency as well as a robust P3 for the deviant tone. Importantly, there was no difference between groups in these auditory attention effects. The results suggest that basic mechanisms of auditory attention are largely normal in children who are proficient cochlear implant users, but that visual attention may be altered. Ultimately, a better understanding of how selective attention influences sensory perception in cochlear implant users will be important for optimising habilitation strategies. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  18. MR imaging of the cochlear modiolus after intratympanic administration of Gd-DTPA

    International Nuclear Information System (INIS)

    Kawai, Hisashi; Naganawa, Shinji; Ishihara, Shunichi; Sone, Michihiko; Nakashima, Tsutomu

    2010-01-01

    We evaluated whether enhancement of the cochlear modiolus could be visualized 24 hours after intratympanic injection of gadolinium diethylenetriamine penta-acetic acid (Gd-DTPA) using a 3-dimensional real inversion recovery sequence combined with a 32-channel head coil at 3 tesla. Intratympanic injection of Gd-DTPA has been reported for visualizing endolymphatic hydrops in Meniere's disease, and its use has shown communication between the cochlear perilymph and cerebrospinal fluid in the internal auditory canal. Although the cochlear modiolus has been considered the route for this communication, this has not been confirmed through direct visualization of its enhancement. We qualitatively and quantitatively evaluated the presence of contrast enhancement in the modiolus in 19 patients with clinically suspected endolymphatic hydrops or hearing loss who underwent imaging as described above. The contrast ratio (CR) between the cochlear modiolus and cerebellar white matter on the injected side was 1.09±1.23, and that on the non-injected side was -0.48±0.38 (P<0.01). In all subjects, the CR value was larger on the injected than non-injected side, and enhancement of the cochlear modiolus was also recognized visually. Intratympanic Gd-DTPA can be administered to visualize enhancement of the cochlear modiolus and may thereby reveal its functional anatomy. (author)

  19. Studying inner ear protein–protein interactions using FRET and FLIM

    OpenAIRE

    Hallworth, Richard; Currall, Benjamin; Nichols, Michael G.; Wu, Xudong; Zuo, Jian

    2006-01-01

    Molecular genetic studies of the inner ear have recently revealed a large number of previously undescribed proteins, but their functions remain unclear. Optical methods such as FRET and FLIM are just beginning to be applied to the study of functional interactions between novel inner ear proteins. This review discusses the various methods for employing FRET and FLIM in protein–protein interaction studies, their advantages and pitfalls, with examples drawn from inner ear studies.

  20. Pitch and loudness matching of unmodulated and modulated stimuli in cochlear implantees.

    Science.gov (United States)

    Vandali, Andrew; Sly, David; Cowan, Robert; van Hoesel, Richard

    2013-08-01

    The pitch elicited by unmodulated and amplitude modulated electrical pulse trains was examined with six adult cochlear implantees. In addition, for three of those subjects who had some hearing in their contralateral ear, the pitch of unmodulated electrical pulse trains was compared to that of complex harmonic acoustic tones. In the first experiment, pulse rate discrimination and the effects of place and level differences on pitch were examined for unmodulated pulse trains. General results were consistent with previous studies showing that variations in pulse rate, while holding loudness fixed, elicit changes in pitch at low rates, but become progressively harder to discriminate as rates approach approximately 300 pulses-per-second. Variations in place or level of stimulation generally produced changes in pitch consistent with tonotopic place and spread of excitation. In the second experiment, pitch and loudness of unmodulated pulse trains were compared with those of amplitude modulated stimuli as a function of modulation depth, rate, and shape, and presentation level. The pitch elicited by an amplitude modulated pulse train was generally higher than that of an unmodulated pulse train with a pulse rate equal to the modulation rate, and generally decreased toward that of the unmodulated pulse train as modulation depth or rate increased, or as presentation level decreased. Sharper/narrower modulation produced lower pitch. In the final experiment, the pitch heights of acoustic complex harmonic tones and unmodulated pulse trains were compared. When electrical pulse rate was equal to the fundamental frequency of the acoustic tone, similar pitch heights were elicited. The results from these experiments indicate that F0 rate pitch derived from the temporal envelope in existing clinical cochlear implant strategies may often be higher than that of acoustic harmonic tones at the same F0 in normal hearing, and that pitch growth with increasing F0 may be shallower. The

  1. Global Ear. Werke 2001 - 2006

    Index Scriptorium Estoniae

    2006-01-01

    Dresdenis muusikafestivalil "Global Ear" 23.3.03 esitusel Eesti heliloojate muusika: Helena Tulve "lumineux/opaque", Jaan Rääts "Meditation", Mirjam Tally "Aura", Mati Kuulberg "Sonate Nr.4", Mari Vihmand "Seitsmele"

  2. Three dimensional and high resolution magnetic resonance imaging of the inner ear. Normal ears and anomaly scanned with 3D-CISS sequence

    Energy Technology Data Exchange (ETDEWEB)

    Edamatsu, Hideo [Dokkyo Univ., Saitama (Japan). Koshigaya Hospital; Uechi, Yoko; Honjyo, Shiro; Yamashita, Koichi; Tonami, Hisao

    1997-12-01

    The MRI system used in this study was a new scanning sequence, 3D-CISS (Three dimensional-constructive interference in steady state) with 1.5 Tesla. Ten normal ears and one ear with Mondini type anomaly were scanned and reconstructed. In imagings of normal inner ears, the cochlea has three spiral layers; basal, middle and apical turns. Each turn was separated into three parts; the scala vestibuli, osseous spiral lamina and scala tympani. Three semicircular ducts, utricle and saccule were also reconstructed in one frame. In the inner ear of Mondini anomaly, 3D MRI showed cochlear aplasia, hypoplasia of semicircular ducts and widely dilated vestibule. The imaging was identical with findings of ``common cavity``. The anomaly was easily recognized in 3D MRI more than in 2D imagings. The detailed and cubic imagings of the Mondini anomaly in 3D MRI could not be observed with conventional 2D MRI. 3D MRI is not invasive method and can scan a target very quickly. (author)

  3. Multicenter clinical trial of the Nucleus Hybrid S8 cochlear implant: Final outcomes.

    Science.gov (United States)

    Gantz, Bruce J; Dunn, Camille; Oleson, Jacob; Hansen, Marlan; Parkinson, Aaron; Turner, Christopher

    2016-04-01

    The concept of expanding electrical speech processing to those with more residual acoustic hearing with a less-invasive shorter cochlear implant (CI) has been ongoing since 1999. A multicenter study of the Nucleus Hybrid S8 CI took place between 2002 and 2011. This report describes the final outcomes of this clinical trial. Multicenter, longitudinal, single-subject design. Eighty-seven subjects received a Nucleus Hybrid S8 CI in their poorer ear. Speech perception in quiet (Consonant-Nucleus-Consonant [CNC] words) and in noise (Bamford-Kowal-Bench Sentences-In-Noise [BKB-SIN]) were collected pre- and postoperatively at 3, 6, and 12 months. Subjective questionnaire data using the Abbreviated Profile for Hearing Aid Benefit (APHAB) were also collected. Some level of hearing preservation was accomplished in 98% subjects, with 90% maintaining a functional low-frequency pure-tone average (LFPTA) at initial activation. By 12 months, five subjects had total hearing loss, and 80% of subjects maintained functional hearing. CNC words demonstrated that 82.5% and 87.5% of subjects had significant improvements in the hybrid and combined conditions, respectively. The majority had improvements with BKB-SIN. Results also indicated that as long as subjects maintained at least a severe LFPTA, there was significant improvement in speech understanding. Furthermore, all subjects reported positive improvements in hearing in three of the four subscales of the APHAB. The concept of hybrid speech processing has significant advantages for subjects with residual low-frequency hearing. In this study, the Nucleus Hybrid S8 provided improved word understanding in quiet and noise. Additionally, there appears to be stability of the residual hearing after initial activation of the device. 2c. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  4. In situ Probe Microphone Measurement for Testing the Direct Acoustical Cochlear Stimulator

    Directory of Open Access Journals (Sweden)

    Christof Stieger

    2017-08-01

    Full Text Available Hypothesis: Acoustical measurements can be used for functional control of a direct acoustic cochlear stimulator (DACS.Background: The DACS is a recently released active hearing implant that works on the principle of a conventional piston prosthesis driven by the rod of an electromagnetic actuator. An inherent part of the DACS actuator is a thin titanium diaphragm that allows for movement of the stimulation rod while hermetically sealing the housing. In addition to mechanical stimulation, the actuator emits sound into the mastoid cavity because of the motion of the diaphragm.Methods: We investigated the use of the sound emission of a DACS for intra-operative testing. We measured sound emission in the external auditory canal (PEAC and velocity of the actuators stimulation rod (Vact in five implanted ears of whole-head specimens. We tested the influence various positions of the loudspeaker and a probe microphone on PEAC and simulated implant malfunction in one example.Results: Sound emission of the DACS with a signal-to-noise ratio >10 dB was observed between 0.5 and 5 kHz. Simulated implant misplacement or malfunction could be detected by the absence or shift in the characteristic resonance frequency of the actuator. PEAC changed by <6 dB for variations of the microphone and loudspeaker position.Conclusion: Our data support the feasibility of acoustical measurements for in situ testing of the DACS implant in the mastoid cavity as well as for post-operative monitoring of actuator function.

  5. Implante coclear em crianças pós-linguais: resultados funcionais após 10 anos da cirurgia Cochlear implant in postlingual children: functional results 10 years after the surgery

    Directory of Open Access Journals (Sweden)

    Liege Franzini Tanamati

    2012-04-01

    Full Text Available Os benefícios do implante coclear (IC às habilidades comunicativas são obtidos ao longo de anos de uso. Há poucos estudos sobre os resultados a longo prazo em crianças pós-linguais que cresceram usando o dispositivo. OBJETIVO: Reportar os resultados funcionais em crianças pós-linguais, após 10 anos de uso do dispositivo. MATERIAL E MÉTODO: Dez crianças pós-linguais, implantadas antes dos 18 anos, participaram deste estudo. Foram avaliadas: a percepção da fala para sentenças e a inteligibilidade de fala. Informações sobre o uso/funcionamento do dispositivo e nível acadêmico/ocupacional foram documentadas. Desenho científico: Estudo de série. RESULTADOS: O reconhecimento para sentenças no silêncio foi igual a 73% e, no ruído, 40%. Para o método de transcrição, a média de acertos foi igual a 92% e, na escala de inteligibilidade, 4.15. Não houve falhas no dispositivo interno. Três participantes haviam concluído o ensino superior e, outros cinco, o ensino médio. Oito participantes estavam empregados. CONCLUSÃO: Este estudo mostrou que o IC é um procedimento seguro e confiável. As crianças pós-linguais após 10 anos de uso do IC alcançaram resultados funcionais em relação à percepção e a inteligibilidade da fala, concluíram ao menos o ensino superior e estavam inseridas no mercado de trabalho.The benefits of cochlear implants (CI for communication skills are obtained over the years. There are but a few studies regarding the long-term outcomes in postlingual deaf children who grew up using the electronic device. AIM: To assess the functional results in a group of postlingual children, 10 years after using a CI. METHODS: Ten postlingual deaf children, implanted before 18 years of age, participated in this study. We assessed: sentence recognition and speech intelligibility. We documented: device use and function and the patient's academic/occupational status. Study design: series. RESULTS: The mean scores were

  6. Libyan cochlear implant programme: achievements, difficulties, and ...

    African Journals Online (AJOL)

    Cochlear implantation has become established worldwide as a safe and effective method of auditory rehabilitation of selected severely and profound deaf children and adults. Over 100,000 patients have received cochlear implants worldwide with the paediatric population proving to be the main beneficiaries. The Libyan ...

  7. The Cochlear Baha 4 Attract System - design concepts, surgical technique and early clinical results.

    Science.gov (United States)

    Clamp, Philip J; Briggs, Robert J S

    2015-05-01

    Bone conduction implant systems utilize osseointegrated fixtures to transmit sound through the bones of the skull. They allow patients with hearing loss to receive acoustic signals directly to the inner ear, bypassing the outer and middle ear. The new Cochlear™ Baha(®) Attract System (Cochlear Bone Anchored Solutions AB, Mölnlycke, Sweden) has been designed as a non-skin penetration hearing implant. The system uses magnetic coupling to hold the external sound processor in place and transmit acoustic energy. An implantable magnet is anchored to the skull via a single osseointegrated fixture, maximizing the efficiency of energy sound transfer. The interposed soft tissue is protected by a SoftWear pad that evenly distributes pressure in order to minimize the risk of pressure necrosis. This article summarizes the design features and early clinical results of the Baha 4 Attract System and provides context as to its place in the broader hearing aid market.

  8. Dependence of distortion-product otoacoustic emissions on primary levels in normal and impaired ears. I. Effects of decreasing L2 below L1.

    Science.gov (United States)

    Whitehead, M L; McCoy, M J; Lonsbury-Martin, B L; Martin, G K

    1995-04-01

    The 2f1-f2 distortion-product otoacoustic emission (DPOAE) is evoked by two primary tones of frequencies f1 L1 and L2. Previous reports indicate that decreasing L2 below L1 = L2 can; (1) increase DPOAE amplitude in normal ears, and (2) increase the degree to which DPOAE amplitudes are reduced by cochlear trauma. Although both of these factors could be advantageous for clinical applications of DPOAEs, neither has been explored in detail. In the present study, 2f1-f2 DPOAE-amplitude frequency functions were collected from normal and impaired ears of rabbits and humans, with L1 = L2, and with L2 L1, at each of three values of L1. In rabbits, controlled tonal or noise overexposures were used to produce permanent reductions of DPOAE amplitudes. Comparison of pre- and postexposure DPOAE-amplitude frequency functions demonstrated that the frequency-specific reductions of DPOAEs were enhanced by decreasing L2 below L1. In humans, DPOAE-amplitude frequency functions obtained with the various L1 and L2 combinations were collected from 16 normal ears to provide preliminary normative data for each stimulus-level condition. The L1-L2 that produced the maximum DPOAE amplitude in normal ears was systematically dependent on L1. Thus at most frequencies, decreasing L2 below L1 = L2 substantially reduced mean DPOAE amplitude when L1 > or = 75 dB SPL, but increased mean DPOAE amplitudes at L1 = 65 dB SPL. However, the increase of mean DPOAE amplitude obtained by decreasing L2 below L1 = 65 dB SPL was small, being less than 3.5 dB at most frequencies. More importantly, at L1 = 65 dB SPL, L2 could be decreased considerably below L1 = L2 without reducing mean DPOAE amplitude relative to that at L1 = L2. Inspection of DPOAE-amplitude frequency functions obtained from subjects with mild or moderate sensorineural hearing losses indicated that, in frequency regions of hearing impairment, decreasing L2 below L1 can enhance the degree of reduction of DPOAEs below the corresponding normative

  9. Free-form image registration of human cochlear μCT data using skeleton similarity as anatomical prior

    DEFF Research Database (Denmark)

    Kjer, Hans Martin; Fagertun, Jens; Vera, Sergio

    2016-01-01

    Better understanding of the anatomical variability of the human cochlear is important for the design and function of Cochlear Implants. Proper non-rigid alignment of high-resolution cochlear μCT data is a challenge for the typical cubic B-spline registration model. In this paper we study one way...... to provide a more global guidance of the alignment. The resulting registrations are evaluated using different metrics for accuracy and model behavior, and compared to the results of a registration without the prior....

  10. Can mobile phone emissions affect auditory functions of cochlea or brain stem?

    Science.gov (United States)

    Sievert, Uwe; Eggert, Siegfried; Pau, Hans Wilhelm

    2005-03-01

    Despite their abundant spread, mobile phones are suspected by a major share of the population to cause adverse effects on health and welfare. The ear as the sense organ next to the individual device has rarely been investigated for short-term effects in this regard. In a previous article, we could not prove any impact on the vestibular part of the inner ear. Our present examinations are concerned with the question whether mobile phone emissions could affect cochlear or auditory brain stem functions. In 12 healthy test persons with normal hearing, auditory brain stem reflexes recordings were performed before, during, and after exposure to electromagnetic emissions by standardized mobile phone devices. Two modes of electromagnetic emissions fields were administered: pulsed and continuous. For acoustic stimulation simultaneous to field exposure, special "plug-in" earphones had to be used. No impact on auditory brain stem reflexes recordings in terms of absolute and interpeak latencies could be found. Together with the results of a previous article concerned with the vestibular part of the inner ear