Objective: To verify the efficacy of a powerful active hearing device in a patient different from far-advanced otosclerosis, specifically when the stapes footplate is mobile. Patient: A patient with severe-to-profound mixed hearing loss, who was not benefiting from the use of a conventional hearing aid, was selected for an inner ear active implant. This was justified by a bone conductive threshold above 60 dB, which had discouraged any other rehabilitative solutions such as a bone conductive implant, or an active middle ear implant (AMEI). Intervention: The hearing device was surgically applied using a combined transmastoid/transcanal approach. During surgery, a mobile stapes were found and was perforated for the insertion of a piston prosthesis, crimped on the new-incus of the device. Main Outcome Measure: The bone conduction threshold was assessed postoperatively to identify any possible surgery-related hearing deterioration. Pure tone audiometry was conducted in a sound field, and a speech reception threshold test was performed with the contralateral ear masked. The hearing outcome was assessed soon after the implant activation (6 weeks after surgery), and 6 months after surgery. Results: Upon activation of the device, a PTA4 of 45 dB was obtained (at 0.5, 1, 2 and 4 kHz). At 6 months after surgery, the speech discrimination score reached 90% at 80 dB SPL. Conclusion: The application of the Codacs device has shown to be compatible with a mobile stapes footplate, as demonstrated in this report. The footplate perforation did not cause any further hearing deterioration, and has allowed to achieve a favorable auditory outcome. Copyright (C) 2016 by Otology & Neurotology, Inc. Image copyright (C) 2010 Wolters Kluwer Health/Anatomical Chart Company
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Τρίτη 19 Απριλίου 2016
Loads and Coupling Modalities Influence the Performance of the Floating Mass Transducer as a Round Window Driver.
Hypothesis: High loads forcing the floating mass transducer (FMT) of a single active middle ear implant toward the round window membrane (RWM) affect the backward stimulation of the cochlea. Background: Various factors influence the backward stimulation of the cochlea. We investigated the effects of various loads applied to the FMT together with different coupling techniques at the fully exposed RWM on the vibration transmission. Methods: Experimental study on temporal bones with the FMT linked to a load cell mounted on a translation stage moving it against the fully exposed RWM with increasing loads up to 200 mN by itself, with interposed perichondrium, cartilage or connected to the round window coupler. Cochlear stimulation is measured by the volume velocities of the stapes footplate using LASER-Doppler-vibrometry. Results: Loads ranging from 5 to 20 mN induce the highest volume velocities of the stapes footplate. Increasing loads decrease the transmission of vibration in the low-frequency range but enhance the transmission of high frequencies. The interposition of perichondrium and cartilage proved to be advantageous. Conclusion: The load applied to the FMT distinctly affects the backward stimulation of the cochlea. Although increasing loads have inverse effects on the transmission of low and high frequencies, high loads lead to an overall decrease of cochlear stimulation. Out of the applied coupling techniques interposed perichondrium and cartilage allow for the most efficient stimulation. Copyright (C) 2016 by Otology & Neurotology, Inc. Image copyright (C) 2010 Wolters Kluwer Health/Anatomical Chart Company
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Neutrophil to Lymphocyte Ratio as a Predictive Marker of Vestibular Schwannoma Growth.
Objective: To examine the predictive value of neutrophil to lymphocyte ratio (NLR) for vestibular schwannoma (VS) growth. Study Design: Retrospective case-control study. Setting: Tertiary, referral center. Patients: Patients with sporadic VS and available NLR obtained within 1 year from the diagnosis were divided into two groups with growing or non-growing tumor. Patients with known conditions affecting NLR were excluded. Interventions: NLR and tumor growth as determined by linear measurements on serial magnetic resonance imaging. Main Outcome Measures: VS growth, demographic factors, and NLR were compared using multi-variant logistic regression and Receiver Operating Characteristic (ROC) curve analysis. Results: A total of 161 patients fulfilled the inclusion criteria, 79 with growing VS (men:women ratio = 43:36, mean age, 61.8 years) and 82 with non-growing tumors (men:women ratio = 37:45, mean age, 64.9 years). Mean NLR for the group with growing VS was 3.34 (SD [standard deviation] = 1.5) and 2.31 (SD = 0.76) for the group with non-growing VS (p = 0.001; 0.03 when adjusted for all parameters). The optimal cut-off point was NLR = 3.05 with positive predictive value 83.8% and 100% for NLR greater than 5.3. ROC analysis of the adjusted data for age, sex, and side, gave an area under the curve of 0.768, indicating NLR as a good independent predictive marker. Interestingly, the size of tumor was statistically significantly higher for the growing VS group (p = 0.001). Conclusion: Despite the low specificity of low NLR, our results indicate high NLR as a good predictive marker for VS growth. Confirmation by prospective studies will have a significant impact on patients' management. Copyright (C) 2016 by Otology & Neurotology, Inc. Image copyright (C) 2010 Wolters Kluwer Health/Anatomical Chart Company
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Correlation of CT MR and Histopathology in Incomplete Partition-II Cochlear Anomaly.
Objective: To correlate the computed tomography (CT) and magnetic resonance imaging (MR) findings in a patient with incomplete partition-type II (IP-II) anomaly with histopathology in a similar human temporal bone specimen. To discover the histologic correlate of a common finding on MR of an "apparent" interscalar septum (IS). Patients: A patient with sensorineural hearing loss and imaging findings characteristic of IP-II, and a patient with histopathologic IP-II anomaly. Intervention: High-resolution CT, MR, and review of postmortem temporal bone histopathology. Main Outcome Measure: Correlation of temporal bone histopathology with CT and MR findings. Results: Consistent findings of IP-II anomaly on CT, absence of the IS between the more distal turns and flattening of the interscalar ridge between the distal basal turn and the middle turn, were present. The signal void surrounding the cochlea on MR also demonstrated flattening of the interscalar ridge. However, a thin band-like area of low T2 signal was seen, which could be mistaken for an IS. Correlation with temporal bone histopathology revealed that the modiolus was foreshortened, and the spiral ganglion neuron dendritic processes continued toward the upper middle turn through the osseous spiral lamina, likely accounting for the MR finding. Conclusion: Correlation of CT, MR, and histopathology in IP-II shows an "apparent" segmentation representing a continuum of neurosensory elements in approximately the same location of the expected location of a normal IS. Care should be taken when interpreting MR imaging in isolation. Understanding the bony outline of the cochlea on imaging may prove to be complementary. Copyright (C) 2016 by Otology & Neurotology, Inc. Image copyright (C) 2010 Wolters Kluwer Health/Anatomical Chart Company
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Cochlear Implant Surgery in the Elderly: The Feasibility of a Modified Suprameatal Approach Under Local Anesthesia.
Objective: Although cochlear implantation is a relatively safe procedure, there is some reticence to subject elderly people, especially those with significant comorbidity, to the risks of general anesthesia. The purpose of the study was to explore the feasibility of cochlear implant surgery under local anesthesia and sedation in elderly people. Study Design: Case report study (Clinical Capsule Report). Setting: Single tertiary academic referral center. Patients: Seven elderly subjects with severe or severe-to-profound sensorineural hearing impairment underwent cochlear implantation under local anesthesia and sedation. All subjects had significant comorbidities with an American Society of Anesthesiologists (ASA) classification 3 to 4 and explicitly expressed their concerns regarding general anesthesia. The subjects were implanted with 24 mm straight electrode array devices via a modified suprameatal approach. Interventions: Therapeutic. Main Outcome Measure: The evaluation of a modified suprameatal approach for cochlear implant surgery under local anesthesia and sedation with respect to patient safety and compliance. Results: Cochlear implantation under local anesthesia and sedation was successful and well tolerated in all subjects. No intra- or postoperative complications occurred. Recovery was quick and all subjects were discharged on the first postoperative day. All subjects would opt again for the procedure under local anesthesia. Conclusion: Cochlear implantation under local anesthesia and sedation was found to be feasible. The modified suprameatal approach lends itself for procedures under local anesthesia, because only minimal drilling is required. The application of this technique provides a safe alternative especially for the elderly with significant comorbidity and increased risks for general anesthesia. Copyright (C) 2016 by Otology & Neurotology, Inc. Image copyright (C) 2010 Wolters Kluwer Health/Anatomical Chart Company
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Impact of Noise Reduction Algorithm in Cochlear Implant Processing on Music Enjoyment.
Objective: Noise reduction algorithm (NRA) in speech processing strategy has positive impact on speech perception among cochlear implant (CI) listeners. We sought to evaluate the effect of NRA on music enjoyment. Study Design: Prospective analysis of music enjoyment. Setting: Academic medical center. Patients: Normal-hearing (NH) adults (N = 16) and CI listeners (N = 9). Intervention: Subjective rating of music excerpts. Main Outcome Measures: NH and CI listeners evaluated country music piece on three enjoyment modalities: pleasantness, musicality, and naturalness. Participants listened to the original version and 20 modified, less complex versions created by including subsets of musical instruments from the original song. NH participants listened to the segments through CI simulation and CI listeners listened to the segments with their usual speech processing strategy, with and without NRA. Results: Decreasing the number of instruments was significantly associated with increase in the pleasantness and naturalness in both NH and CI subjects (p 0.05): this was true for the original and the modified music segments with one to three instruments (p > 0.05). Conclusion: NRA does not affect music enjoyment in CI listener or NH individual with CI simulation. This suggests that strategies to enhance speech processing will not necessarily have a positive impact on music enjoyment. However, reducing the complexity of music shows promise in enhancing music enjoyment and should be further explored. Copyright (C) 2016 by Otology & Neurotology, Inc. Image copyright (C) 2010 Wolters Kluwer Health/Anatomical Chart Company
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Secondary Endolymphatic Hydrops After Acoustic Trauma.
Objective: This study applied an inner ear test battery in patients with secondary hydrops after acoustic trauma to assess the inner ear deficits. Study Design: Retrospective study. Setting: University hospital. Methods: Twenty patients with secondary hydrops after acoustic trauma were assigned to Group A. The interval between noise exposure and the testing time varied from 1 month to 3 years (median 3 months). Another 20 patients without progressive hearing loss for at least 3 years after acoustic trauma were assigned to Group B. There were no significant differences between the two groups in terms of age, sex, laterality, and noise source. Before treatment, all patients received audiometry, and caloric, ocular vestibular-evoked myogenic potential (VEMP), and cervical VEMP (cVEMP) tests. Results: Percentages of abnormal mean hearing level (MHL), cVEMP test, oVEMP test, and caloric test were 75%, 75%, 61%, and 43% in Group A, and 35%, 57%, 61%, and 39% in Group B, respectively. Both groups exhibited a significantly declining sequence in inner ear function. Comparison of the abnormalities in the inner ear test battery between Groups A and B revealed a significant difference in percentages of abnormal MHL, but not in those of abnormal cVEMP, oVEMP, and caloric tests. Conclusion: Secondary hydrops after acoustic trauma occurs mainly on the cochlear part, but less on the vestibular part probably because previous acoustic trauma, i.e., firearms have severely damaged the vestibular partition. Copyright (C) 2016 by Otology & Neurotology, Inc. Image copyright (C) 2010 Wolters Kluwer Health/Anatomical Chart Company
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CT Scan Imaging of the Human Fetal Labyrinth: Case Series Data Throughout Gestation.
Objectives: The inner ear in humans reaches its final configuration and its adult size during fetal life. According to the literature, this occurs between 18 and 25 weeks of amenorrhea (WA). Our goal is to clarify the course of inner ear size development. Methods: Using computed tomography (CT) scanner, we studied 13 measurements in the inner ear of a collection of 153 fetuses from 21 to 40 WA. Results: We found no side-related differences or sexual dimorphism in the measurements. Cochlear and vestibular bone measurements did not show growth from 21 to 40 WA, with the exception of the lateral semicircular canal (LSCC) bony island, which grows until 25 WA. Internal auditory canal (IAC) and cochlear aqueduct (CA) growth are correlated with gestational age. As our cochlear measurements are similar to those of infants and adults, in accordance with the literature we conclude that the cochlea has reached its adult size before 21 WA. The continuous growth of the IAC and CA is linked to petrous ossification that continues during fetal gestation and after birth. Conclusion: We confirm that the cochlea reaches its adult size during the second trimester of fetal life. Copyright (C) 2016 by Otology & Neurotology, Inc. Image copyright (C) 2010 Wolters Kluwer Health/Anatomical Chart Company
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Test-retest and Interrater Reliability of the Video Head Impulse Test in the Pediatric Population.
Objective: Determine reliability of horizontal and vertical video head impulse test (vHIT) and effect of maturation on angular vestibular ocular reflex (AVOR) gain estimations and peak head velocities of individual canals in typically developing children and adolescents. Design: Reliability study. Setting: University research laboratory Subjects: Two normal adults mean age 51.5 +/- 0.5 years and 28 typically developing children and adolescents mean age 10 +/- 3.5 years (range, 4.33-17.25 years). Main Outcome Measures: Mean AVOR gain estimate and peak head impulse velocity for individual canals. Results: In adult sample, mean AVOR gain estimates were 1.00 to 1.04 for lateral and 1.07 to 1.13 for vertical canals. In pediatric sample, mean AVOR gain estimates were 1.00 to 1.04 for lateral and 1.03 to 1.08 vertical canals. Mean AVOR gain intrarater reliability scores (intraclass correlation coefficient [ICC] >= 0.821 = 0.800
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The Association of External and Middle Ear Anomaly and Mandibular Morphology in Congenital Microtia.
Objective: To investigate the relationship between the severity of ear anomaly and mandibular dysplasia in congenital microtia. Study Design: Retrospective case review. Setting: Sapporo Medical University Hospital. Patients: Congenital microtia: 44 patients over a period of 4 years. Interventions: The height of the condylar process of the mandible was assessed by three-dimensional computed tomography (CT), and the patients were divided into three groups based on the ratio of the condylar process height on the affected side to that on the unaffected side: Group A, >=1.00; Group B, 0.99 to 0.85; Group C,
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Comparison of Audiological Results Between a Transcutaneous and a Percutaneous Bone Conduction Instrument in Conductive Hearing Loss.
Objectives: In conductive, mixed hearing losses and single-sided-deafness bone-anchored hearing aids are a well-established treatment. The transcutaneous transmission across the intact skin avoids the percutaneous abutment of a bone-anchored device with the usual risk of infections and requires less care. In this study, the audiological results of the Bonebridge transcutaneous bone conduction implant (MED-EL) are compared to the generally used percutaneous device BP100 (Cochlear Ltd., Sydney, Australia). Methods: Ten patients implanted with the transcutaneous hearing implant were compared to 10 matched patients implanted with a percutaneous device. Tests included pure-tone AC and BC thresholds and unaided and aided sound field thresholds. Speech intelligibility was determined in quiet using the Freiburg monosyllable test and in noise with the Oldenburg sentence test (OLSA) in sound field with speech from the front (S0). The subjective benefit was assessed with the Abbreviated Profile of Hearing Aid Benefit. Results: In comparison with the unaided condition there was a significant improvement in aided thresholds, word recognition scores (WRS), and speech reception thresholds (SRT) in noise, measured in sound field, for both devices. The comparison of the two devices revealed a minor but not significant difference in functional gain (Bonebridge: PTA = 27.5 dB [mean]; BAHA: PTA = 26.3 dB [mean]). No significant difference between the two devices was found when comparing the improvement in WRSs and SRTs (Bonebridge: improvement WRS = 80% [median], improvement SRT = 6.5 dB SNR [median]; BAHA: improvement WRS = 77.5% [median], BAHA: improvement SRT = 6.9 dB SNR [median]). Conclusion: Our data show that the transcutaneous bone conduction hearing implant is an audiologically equivalent alternative to percutaneous bone-anchored devices in conductive hearing loss with a minor sensorineural hearing loss component. Copyright (C) 2016 by Otology & Neurotology, Inc. Image copyright (C) 2010 Wolters Kluwer Health/Anatomical Chart Company
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Cochlear Implant Rate Pitch and Melody Perception as a Function of Place and Number of Electrodes
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.
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The Perception of Auditory Motion
The growing availability of efficient and relatively inexpensive virtual auditory display technology has provided new research platforms to explore the perception of auditory motion. At the same time, deployment of these technologies in command and control as well as in entertainment roles is generating an increasing need to better understand the complex processes underlying auditory motion perception. This is a particularly challenging processing feat because it involves the rapid deconvolution of the relative change in the locations of sound sources produced by rotational and translations of the head in space (self-motion) to enable the perception of actual source motion. The fact that we perceive our auditory world to be stable despite almost continual movement of the head demonstrates the efficiency and effectiveness of this process. This review examines the acoustical basis of auditory motion perception and a wide range of psychophysical, electrophysiological, and cortical imaging studies that have probed the limits and possible mechanisms underlying this perception.
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An Investigation of Multidimensional Voice Program Parameters in Three Different Databases for Voice Pathology Detection and Classification
Publication date: Available online 19 April 2016
Source:Journal of Voice
Author(s): Ahmed Al-nasheri, Ghulam Muhammad, Mansour Alsulaiman, Zulfiqar Ali, Tamer A. Mesallam, Mohamed Farahat, Khalid H. Malki, Mohamed A. Bencherif
Background and ObjectiveAutomatic voice-pathology detection and classification systems may help clinicians to detect the existence of any voice pathologies and the type of pathology from which patients suffer in the early stages. The main aim of this paper is to investigate Multidimensional Voice Program (MDVP) parameters to automatically detect and classify the voice pathologies in multiple databases, and then to find out which parameters performed well in these two processes.Materials and MethodsSamples of the sustained vowel /a/ of normal and pathological voices were extracted from three different databases, which have three voice pathologies in common. The selected databases in this study represent three distinct languages: (1) the Arabic voice pathology database; (2) the Massachusetts Eye and Ear Infirmary database (English database); and (3) the Saarbruecken Voice Database (German database). A computerized speech lab program was used to extract MDVP parameters as features, and an acoustical analysis was performed. The Fisher discrimination ratio was applied to rank the parameters. A t test was performed to highlight any significant differences in the means of the normal and pathological samples.ResultsThe experimental results demonstrate a clear difference in the performance of the MDVP parameters using these databases. The highly ranked parameters also differed from one database to another. The best accuracies were obtained by using the three highest ranked MDVP parameters arranged according to the Fisher discrimination ratio: these accuracies were 99.68%, 88.21%, and 72.53% for the Saarbruecken Voice Database, the Massachusetts Eye and Ear Infirmary database, and the Arabic voice pathology database, respectively.
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Source:Journal of Voice
Author(s): Ahmed Al-nasheri, Ghulam Muhammad, Mansour Alsulaiman, Zulfiqar Ali, Tamer A. Mesallam, Mohamed Farahat, Khalid H. Malki, Mohamed A. Bencherif
Background and ObjectiveAutomatic voice-pathology detection and classification systems may help clinicians to detect the existence of any voice pathologies and the type of pathology from which patients suffer in the early stages. The main aim of this paper is to investigate Multidimensional Voice Program (MDVP) parameters to automatically detect and classify the voice pathologies in multiple databases, and then to find out which parameters performed well in these two processes.Materials and MethodsSamples of the sustained vowel /a/ of normal and pathological voices were extracted from three different databases, which have three voice pathologies in common. The selected databases in this study represent three distinct languages: (1) the Arabic voice pathology database; (2) the Massachusetts Eye and Ear Infirmary database (English database); and (3) the Saarbruecken Voice Database (German database). A computerized speech lab program was used to extract MDVP parameters as features, and an acoustical analysis was performed. The Fisher discrimination ratio was applied to rank the parameters. A t test was performed to highlight any significant differences in the means of the normal and pathological samples.ResultsThe experimental results demonstrate a clear difference in the performance of the MDVP parameters using these databases. The highly ranked parameters also differed from one database to another. The best accuracies were obtained by using the three highest ranked MDVP parameters arranged according to the Fisher discrimination ratio: these accuracies were 99.68%, 88.21%, and 72.53% for the Saarbruecken Voice Database, the Massachusetts Eye and Ear Infirmary database, and the Arabic voice pathology database, respectively.
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Quantifying the Subharmonic Mucosal Wave in Excised Larynges via Digital Kymography
Publication date: Available online 19 April 2016
Source:Journal of Voice
Author(s): Yu Zhang, Nanmu Huang, William Calawerts, Lin Li, Allison L. Maytag, Jack J. Jiang
ObjectivesIn this paper, a nonlinear least squares fitting method was proposed to quantify subharmonic mucosal waves.Study Design and MethodsSubharmonic mucosal waves from 10 excised canine larynges were recorded using digital kymography and analyzed using nonlinear least squares and linear least squares methods. Amplitudes of fundamental and subharmonic mucosal wave components of right-upper, right-lower, left-upper, and left-lower vocal fold lips were calculated. Lastly, phase differences of fundamental and subharmonic components of the left and right vocal folds were compared.ResultsThe results showed that the nonlinear least squares analysis method provides a more effective complement to the linear fitting method for subharmonic mucosal wave extraction. There was a significant difference in amplitudes between the subharmonic and the fundamental components of mucosal waves (P < 0.05). The phase differences of the fundamental and the subharmonic components of the right and left vocal folds were not significantly different.ConclusionsThe application of the nonlinear least squares analysis method in digital kymography is useful for the characterization of subharmonic mucosal waves.
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Source:Journal of Voice
Author(s): Yu Zhang, Nanmu Huang, William Calawerts, Lin Li, Allison L. Maytag, Jack J. Jiang
ObjectivesIn this paper, a nonlinear least squares fitting method was proposed to quantify subharmonic mucosal waves.Study Design and MethodsSubharmonic mucosal waves from 10 excised canine larynges were recorded using digital kymography and analyzed using nonlinear least squares and linear least squares methods. Amplitudes of fundamental and subharmonic mucosal wave components of right-upper, right-lower, left-upper, and left-lower vocal fold lips were calculated. Lastly, phase differences of fundamental and subharmonic components of the left and right vocal folds were compared.ResultsThe results showed that the nonlinear least squares analysis method provides a more effective complement to the linear fitting method for subharmonic mucosal wave extraction. There was a significant difference in amplitudes between the subharmonic and the fundamental components of mucosal waves (P < 0.05). The phase differences of the fundamental and the subharmonic components of the right and left vocal folds were not significantly different.ConclusionsThe application of the nonlinear least squares analysis method in digital kymography is useful for the characterization of subharmonic mucosal waves.
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Cochlear Implant Rate Pitch and Melody Perception as a Function of Place and Number of Electrodes
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.
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The Perception of Auditory Motion
The growing availability of efficient and relatively inexpensive virtual auditory display technology has provided new research platforms to explore the perception of auditory motion. At the same time, deployment of these technologies in command and control as well as in entertainment roles is generating an increasing need to better understand the complex processes underlying auditory motion perception. This is a particularly challenging processing feat because it involves the rapid deconvolution of the relative change in the locations of sound sources produced by rotational and translations of the head in space (self-motion) to enable the perception of actual source motion. The fact that we perceive our auditory world to be stable despite almost continual movement of the head demonstrates the efficiency and effectiveness of this process. This review examines the acoustical basis of auditory motion perception and a wide range of psychophysical, electrophysiological, and cortical imaging studies that have probed the limits and possible mechanisms underlying this perception.
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Cochlear Implant Rate Pitch and Melody Perception as a Function of Place and Number of Electrodes
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.
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The Perception of Auditory Motion
The growing availability of efficient and relatively inexpensive virtual auditory display technology has provided new research platforms to explore the perception of auditory motion. At the same time, deployment of these technologies in command and control as well as in entertainment roles is generating an increasing need to better understand the complex processes underlying auditory motion perception. This is a particularly challenging processing feat because it involves the rapid deconvolution of the relative change in the locations of sound sources produced by rotational and translations of the head in space (self-motion) to enable the perception of actual source motion. The fact that we perceive our auditory world to be stable despite almost continual movement of the head demonstrates the efficiency and effectiveness of this process. This review examines the acoustical basis of auditory motion perception and a wide range of psychophysical, electrophysiological, and cortical imaging studies that have probed the limits and possible mechanisms underlying this perception.
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The Intelligibility of Interrupted Speech: Cochlear Implant Users and Normal Hearing Listeners
Abstract
Compared with normal-hearing listeners, cochlear implant (CI) users display a loss of intelligibility of speech interrupted by silence or noise, possibly due to reduced ability to integrate and restore speech glimpses across silence or noise intervals. The present study was conducted to establish the extent of the deficit typical CI users have in understanding interrupted high-context sentences as a function of a range of interruption rates (1.5 to 24 Hz) and duty cycles (50 and 75 %). Further, factors such as reduced signal quality of CI signal transmission and advanced age, as well as potentially lower speech intelligibility of CI users even in the lack of interruption manipulation, were explored by presenting young, as well as age-matched, normal-hearing (NH) listeners with full-spectrum and vocoded speech (eight-channel and speech intelligibility baseline performance matched). While the actual CI users had more difficulties in understanding interrupted speech and taking advantage of faster interruption rates and increased duty cycle than the eight-channel noise-band vocoded listeners, their performance was similar to the matched noise-band vocoded listeners. These results suggest that while loss of spectro-temporal resolution indeed plays an important role in reduced intelligibility of interrupted speech, these factors alone cannot entirely explain the deficit. Other factors associated with real CIs, such as aging or failure in transmission of essential speech cues, seem to additionally contribute to poor intelligibility of interrupted speech.
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Transmucosal Gas-Loss Rates in Middle Ears Initially Filled with O2 or CO2
Publication date: Available online 19 April 2016
Source:Hearing Research
Author(s): Romain E. Kania, Benjamin Verillaud, Bernard Ars, Patrice Tran Ba Huy, Philippe Herman, Amos Ar
This study investigates the role of different gases in clearance of gas in the middle ear cavity (ME) by its mucosal blood flow. A rat model was used to measure gas volume changes in the ME cavity at constant pressure without ventilation. We disturbed the normal gas composition of the ME by filling it with O2 or CO2, measured the consequent changes in gas volume over time and compared these results with previously obtained ones for air and N2. The first 5 min of the primary transient phase (phase I) for O2 or CO2 was characterized by a volume loss decrease of -0.49 ± 0.34 μL and -46.28 ± 8.49 μL, respectively, with volume loss increase for air and N2 differing greatly, at +0.17 ± 0.17 and +2.31 ± 0.81, respectively. The CO2 value of -46.28 μL showed that a volume of gas equivalent to that of the ME cleft volume was eliminated within the first 5 min. In the second phase (phase II), all gases showed a linear decrease in volume, which presumably represents a steady-state gas loss rate. However, the gas loss rate of -0.307 ± 0.170 μL∙min-1 for O2-filled MEs was significantly higher than the mean of -0.124 μL∙min-1 for all other gases. We used a previously established mathematical model to calculate the effective ME mucosal blood flow rate under steady-state (phase II) conditions. The blood flow results for O2-filled MEs differed greatly from those of the other gases (89.0 ± 49.28 vs. 26.5 μL∙min-1, on average), which suggest that the model used to calculate blood flow should be modified if used with O2-filled MEs. Further work should involve a comparison of our method with different methods to verify ME blood flow rate.
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Source:Hearing Research
Author(s): Romain E. Kania, Benjamin Verillaud, Bernard Ars, Patrice Tran Ba Huy, Philippe Herman, Amos Ar
This study investigates the role of different gases in clearance of gas in the middle ear cavity (ME) by its mucosal blood flow. A rat model was used to measure gas volume changes in the ME cavity at constant pressure without ventilation. We disturbed the normal gas composition of the ME by filling it with O2 or CO2, measured the consequent changes in gas volume over time and compared these results with previously obtained ones for air and N2. The first 5 min of the primary transient phase (phase I) for O2 or CO2 was characterized by a volume loss decrease of -0.49 ± 0.34 μL and -46.28 ± 8.49 μL, respectively, with volume loss increase for air and N2 differing greatly, at +0.17 ± 0.17 and +2.31 ± 0.81, respectively. The CO2 value of -46.28 μL showed that a volume of gas equivalent to that of the ME cleft volume was eliminated within the first 5 min. In the second phase (phase II), all gases showed a linear decrease in volume, which presumably represents a steady-state gas loss rate. However, the gas loss rate of -0.307 ± 0.170 μL∙min-1 for O2-filled MEs was significantly higher than the mean of -0.124 μL∙min-1 for all other gases. We used a previously established mathematical model to calculate the effective ME mucosal blood flow rate under steady-state (phase II) conditions. The blood flow results for O2-filled MEs differed greatly from those of the other gases (89.0 ± 49.28 vs. 26.5 μL∙min-1, on average), which suggest that the model used to calculate blood flow should be modified if used with O2-filled MEs. Further work should involve a comparison of our method with different methods to verify ME blood flow rate.
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Transmucosal Gas-Loss Rates in Middle Ears Initially Filled with O2 or CO2
Publication date: Available online 19 April 2016
Source:Hearing Research
Author(s): Romain E. Kania, Benjamin Verillaud, Bernard Ars, Patrice Tran Ba Huy, Philippe Herman, Amos Ar
This study investigates the role of different gases in clearance of gas in the middle ear cavity (ME) by its mucosal blood flow. A rat model was used to measure gas volume changes in the ME cavity at constant pressure without ventilation. We disturbed the normal gas composition of the ME by filling it with O2 or CO2, measured the consequent changes in gas volume over time and compared these results with previously obtained ones for air and N2. The first 5 min of the primary transient phase (phase I) for O2 or CO2 was characterized by a volume loss decrease of -0.49 ± 0.34 μL and -46.28 ± 8.49 μL, respectively, with volume loss increase for air and N2 differing greatly, at +0.17 ± 0.17 and +2.31 ± 0.81, respectively. The CO2 value of -46.28 μL showed that a volume of gas equivalent to that of the ME cleft volume was eliminated within the first 5 min. In the second phase (phase II), all gases showed a linear decrease in volume, which presumably represents a steady-state gas loss rate. However, the gas loss rate of -0.307 ± 0.170 μL∙min-1 for O2-filled MEs was significantly higher than the mean of -0.124 μL∙min-1 for all other gases. We used a previously established mathematical model to calculate the effective ME mucosal blood flow rate under steady-state (phase II) conditions. The blood flow results for O2-filled MEs differed greatly from those of the other gases (89.0 ± 49.28 vs. 26.5 μL∙min-1, on average), which suggest that the model used to calculate blood flow should be modified if used with O2-filled MEs. Further work should involve a comparison of our method with different methods to verify ME blood flow rate.
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Source:Hearing Research
Author(s): Romain E. Kania, Benjamin Verillaud, Bernard Ars, Patrice Tran Ba Huy, Philippe Herman, Amos Ar
This study investigates the role of different gases in clearance of gas in the middle ear cavity (ME) by its mucosal blood flow. A rat model was used to measure gas volume changes in the ME cavity at constant pressure without ventilation. We disturbed the normal gas composition of the ME by filling it with O2 or CO2, measured the consequent changes in gas volume over time and compared these results with previously obtained ones for air and N2. The first 5 min of the primary transient phase (phase I) for O2 or CO2 was characterized by a volume loss decrease of -0.49 ± 0.34 μL and -46.28 ± 8.49 μL, respectively, with volume loss increase for air and N2 differing greatly, at +0.17 ± 0.17 and +2.31 ± 0.81, respectively. The CO2 value of -46.28 μL showed that a volume of gas equivalent to that of the ME cleft volume was eliminated within the first 5 min. In the second phase (phase II), all gases showed a linear decrease in volume, which presumably represents a steady-state gas loss rate. However, the gas loss rate of -0.307 ± 0.170 μL∙min-1 for O2-filled MEs was significantly higher than the mean of -0.124 μL∙min-1 for all other gases. We used a previously established mathematical model to calculate the effective ME mucosal blood flow rate under steady-state (phase II) conditions. The blood flow results for O2-filled MEs differed greatly from those of the other gases (89.0 ± 49.28 vs. 26.5 μL∙min-1, on average), which suggest that the model used to calculate blood flow should be modified if used with O2-filled MEs. Further work should involve a comparison of our method with different methods to verify ME blood flow rate.
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Transmucosal Gas-Loss Rates in Middle Ears Initially Filled with O2 or CO2
Source:Hearing Research
Author(s): Romain E. Kania, Benjamin Verillaud, Bernard Ars, Patrice Tran Ba Huy, Philippe Herman, Amos Ar
This study investigates the role of different gases in clearance of gas in the middle ear cavity (ME) by its mucosal blood flow. A rat model was used to measure gas volume changes in the ME cavity at constant pressure without ventilation. We disturbed the normal gas composition of the ME by filling it with O2 or CO2, measured the consequent changes in gas volume over time and compared these results with previously obtained ones for air and N2. The first 5 min of the primary transient phase (phase I) for O2 or CO2 was characterized by a volume loss decrease of -0.49 ± 0.34 μL and -46.28 ± 8.49 μL, respectively, with volume loss increase for air and N2 differing greatly, at +0.17 ± 0.17 and +2.31 ± 0.81, respectively. The CO2 value of -46.28 μL showed that a volume of gas equivalent to that of the ME cleft volume was eliminated within the first 5 min. In the second phase (phase II), all gases showed a linear decrease in volume, which presumably represents a steady-state gas loss rate. However, the gas loss rate of -0.307 ± 0.170 μL∙min-1 for O2-filled MEs was significantly higher than the mean of -0.124 μL∙min-1 for all other gases. We used a previously established mathematical model to calculate the effective ME mucosal blood flow rate under steady-state (phase II) conditions. The blood flow results for O2-filled MEs differed greatly from those of the other gases (89.0 ± 49.28 vs. 26.5 μL∙min-1, on average), which suggest that the model used to calculate blood flow should be modified if used with O2-filled MEs. Further work should involve a comparison of our method with different methods to verify ME blood flow rate.
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Transmucosal Gas-Loss Rates in Middle Ears Initially Filled with O2 or CO2
Source:Hearing Research
Author(s): Romain E. Kania, Benjamin Verillaud, Bernard Ars, Patrice Tran Ba Huy, Philippe Herman, Amos Ar
This study investigates the role of different gases in clearance of gas in the middle ear cavity (ME) by its mucosal blood flow. A rat model was used to measure gas volume changes in the ME cavity at constant pressure without ventilation. We disturbed the normal gas composition of the ME by filling it with O2 or CO2, measured the consequent changes in gas volume over time and compared these results with previously obtained ones for air and N2. The first 5 min of the primary transient phase (phase I) for O2 or CO2 was characterized by a volume loss decrease of -0.49 ± 0.34 μL and -46.28 ± 8.49 μL, respectively, with volume loss increase for air and N2 differing greatly, at +0.17 ± 0.17 and +2.31 ± 0.81, respectively. The CO2 value of -46.28 μL showed that a volume of gas equivalent to that of the ME cleft volume was eliminated within the first 5 min. In the second phase (phase II), all gases showed a linear decrease in volume, which presumably represents a steady-state gas loss rate. However, the gas loss rate of -0.307 ± 0.170 μL∙min-1 for O2-filled MEs was significantly higher than the mean of -0.124 μL∙min-1 for all other gases. We used a previously established mathematical model to calculate the effective ME mucosal blood flow rate under steady-state (phase II) conditions. The blood flow results for O2-filled MEs differed greatly from those of the other gases (89.0 ± 49.28 vs. 26.5 μL∙min-1, on average), which suggest that the model used to calculate blood flow should be modified if used with O2-filled MEs. Further work should involve a comparison of our method with different methods to verify ME blood flow rate.
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Transmucosal Gas-Loss Rates in Middle Ears Initially Filled with O2 or CO2
Source:Hearing Research
Author(s): Romain E. Kania, Benjamin Verillaud, Bernard Ars, Patrice Tran Ba Huy, Philippe Herman, Amos Ar
This study investigates the role of different gases in clearance of gas in the middle ear cavity (ME) by its mucosal blood flow. A rat model was used to measure gas volume changes in the ME cavity at constant pressure without ventilation. We disturbed the normal gas composition of the ME by filling it with O2 or CO2, measured the consequent changes in gas volume over time and compared these results with previously obtained ones for air and N2. The first 5 min of the primary transient phase (phase I) for O2 or CO2 was characterized by a volume loss decrease of -0.49 ± 0.34 μL and -46.28 ± 8.49 μL, respectively, with volume loss increase for air and N2 differing greatly, at +0.17 ± 0.17 and +2.31 ± 0.81, respectively. The CO2 value of -46.28 μL showed that a volume of gas equivalent to that of the ME cleft volume was eliminated within the first 5 min. In the second phase (phase II), all gases showed a linear decrease in volume, which presumably represents a steady-state gas loss rate. However, the gas loss rate of -0.307 ± 0.170 μL∙min-1 for O2-filled MEs was significantly higher than the mean of -0.124 μL∙min-1 for all other gases. We used a previously established mathematical model to calculate the effective ME mucosal blood flow rate under steady-state (phase II) conditions. The blood flow results for O2-filled MEs differed greatly from those of the other gases (89.0 ± 49.28 vs. 26.5 μL∙min-1, on average), which suggest that the model used to calculate blood flow should be modified if used with O2-filled MEs. Further work should involve a comparison of our method with different methods to verify ME blood flow rate.
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Labyrinthine concussion following gunshot injury: A case report
10.3109/14992027.2016.1166398<br/>Jamie M. Bogle
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Labyrinthine concussion following gunshot injury: A case report
10.3109/14992027.2016.1166398<br/>Jamie M. Bogle
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Labyrinthine concussion following gunshot injury: A case report
10.3109/14992027.2016.1166398<br/>Jamie M. Bogle
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Labyrinthine concussion following gunshot injury: A case report
10.3109/14992027.2016.1166398<br/>Jamie M. Bogle
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Labyrinthine concussion following gunshot injury: A case report
10.3109/14992027.2016.1166398<br/>Jamie M. Bogle
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Labyrinthine concussion following gunshot injury: A case report
10.3109/14992027.2016.1166398<br/>Jamie M. Bogle
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AC/DC Singer Battles Sensorineural Hearing Loss
In an article posted to CNN.com on April 19, AC/DC lead singer Brian Johnson details his battle with sensorineural hearing loss after years of unprotected noise exposure from concert performances. In the article, he refers to his admission of hearing loss and ultimate decision to cease touring with the band as his “darkest day.” Sadly, Johnson is only one in a long line of musicians, including Pete Townshend, Eric Clapton, Ted Nugent, Phil Collins, will.I.am, and many more, who suffer from tinnitus and/or hearing loss as a consequence of their profession.
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Image reconstruction with uncertainty quantification in photoacoustic tomography
Photoacoustictomography is a hybrid imaging method that combines optical contrast and ultrasound resolution. The goal of photoacoustictomography is to resolve an initial pressure distribution from detectedultrasound waves generated within an object due to an illumination of a short light pulse. In this work, a Bayesian approach to photoacoustictomography is described. The solution of the inverse problem is derived and computation of the point estimates for image reconstruction and uncertainty quantification is described. The approach is investigated with simulations in different detector geometries, including limited view setup, and with different detector properties such as ideal point-like detectors, finite size detectors, and detectors with a finite bandwidth. The results show that the Bayesian approach can be used to provide accurate estimates of the initial pressure distribution, as well as information about the uncertainty of the estimates.
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Military jet noise source imaging using multisource statistically optimized near-field acoustical holography
The identification of acoustic sources is critical to targeted noise reduction efforts for jets on high-performance tactical aircraft. This paper describes the imaging of acoustic sources from a tactical jet using near-field acoustical holography techniques. The measurement consists of a series of scans over the hologram with a dense microphone array. Partial field decomposition methods are performed to generate coherent holograms. Numerical extrapolation of data beyond the measurement aperture mitigates artifacts near the aperture edges. A multisource equivalent wave model is used that includes the effects of the ground reflection on the measurement. Multisource statistically optimized near-field acoustical holography (M-SONAH) is used to reconstruct apparent source distributions between 20 and 1250 Hz at four engine powers. It is shown that M-SONAH produces accurate field reconstructions for both inward and outward propagation in the region spanned by the physical hologram measurement. Reconstructions across the set of engine powers and frequencies suggests that directivity depends mainly on estimated source location; sources farther downstream radiate at a higher angle relative to the inlet axis. At some frequencies and engine powers, reconstructed fields exhibit multiple radiation lobes originating from overlapped source regions, which is a phenomenon relatively recently reported for full-scale jets.
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Shallow water acoustic response and platform motion modeling via a hierarchical Gaussian mixture model
A hierarchical Gaussian mixture model is proposed to characterize shallow water acoustic response functions that are time-varying and sparse. The mixture model is based on the assumption that acoustic paths can be partitioned into two sets. The first is a relatively coherent set of arrivals that on average exhibit Doppler spreading about a mean Doppler and the remaining set is of multiple surface scattered paths that exhibit a spectrally flat Doppler. The hierarchy establishes constraints on the parameters of each of these Gaussian models such that coherent components of the response are both sparse and in the ensemble obey the Doppler spread profile. This is accomplished with a Bernoulli model that indicates the ensonification state of each element in the bi-frequency representation of the acoustic response function. Estimators of the time-varying acoustic response for the full duration of a broadband transmission are developed and employed to compensate for the shared time-varying dilation process among the coherent arrivals. The approach ameliorates response coherence degradation and can be employed to enhance coherent multi-path combining and is a useful alternative to time recursive estimation. The model is tested with acoustic communication recordings taken in shallow water at low signal-to-noise ratios.
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Sensory challenges for trawling bats: Finding transient prey on water surfaces
Bats are able to identify obstacles and prey objects based exclusively on acoustic information acquired via echolocation. To assess the echo information potentially available to the trawling bat Noctilio leporinus, prey objects were ensonified with artificial bat calls and deduced echo target strengths (TS) of the reflected signals. The artificial calls consisted either of constant frequency (CF) or frequency modulated (FM)sounds. Detection distances were calculated for call intensities of N. leporinus emitted in the field and in confined space. Measurements of a transient target consisting of a brief water splash and subsequently expanding water ripples revealed that concentrically expanding water ripples can provide sufficiently loud echoes to be detected by trawling bats. Experiments with stationary targets revealed differences in TS depending on the type of signal used (CF or FM). A calculated maximum detection distance between 4.5 and 13.7 m for all measured targets indicates that prey detection in this very loud calling species occurs much earlier than suggested by estimations based on modifications in echolocation or flight behavior.
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Novel missense mutation in the CLPP gene causes Perrault Syndrome type-3 in a Turkish family.
Novel missense mutation in the CLPP gene causes Perrault Syndrome type-3 in a Turkish family.
J Clin Res Pediatr Endocrinol. 2016 Apr 18;
Authors: Dursun F, Mohamoud HS, Karim N, Naeem M, Jelani M, Kırmızıbekmez H
Abstract
Perrault syndrome (PRLTS) is a heterogeneous group of clinical and genetic disorders in which patients are characterized by sensory neuronal hearing loss, in both sexes and premature ovarian failure or infertility in females. Neurological and hearing loss symptoms appear early in life; however, female infertility obviously cannot be detected before puberty. In addition to this, spastic limbs, muscle weakness, delayed puberty; irregular menstrual cycles have also been observed in PRLTS patients. Mutations in five genes, HSD17B4, HARS2, CLPP, LARS2, and C10orf2, have been reported in five subtypes of PRLTS. Here we report a milder phenotype of PRLTS in a Turkish family in which two affected patients had no neurological findings; however, they both were characterized by sensory neuronal hearing loss and only the female also had secondary amenorrhea and gonadal dysgenesis. Genome-wide homozygosity mapping using 300K SNP microarray analysis together with iScan platform (Illumina, USA) followed by candidate gene Sanger sequencing with ABI 3500 Genetic Analyzer (Life Technologies, USA) were used for molecular diagnosis. We found a novel missense alteration c.624C>G; p.Ile208Met in exon 5 of the CLPP at chromosome 19p13.3. This study expands the mutation spectrum of CLPP pathogenicity in PRLTS type-3 phenotype.
PMID: 27087618 [PubMed - as supplied by publisher]
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