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1.
Otol Neurotol ; 44(1): e1-e7, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36413361

RESUMEN

OBJECTIVES: To develop a model to predict individualized hearing aid benefit. To provide interpretations of model predictions on global and individual levels. METHODS: We compiled a data set of patients with hearing loss who trialed hearing aids and completed the Client Oriented Scale of Improvement (COSI) questionnaire, a validated patient-reported outcome measure of hearing aid benefit. Features included demographic, medical, and audiological measures. The outcome was the COSI score for change in listening ability with hearing aids, scaled from 1 to 5. Model development was performed using fivefold cross-validation repeated three times with hyperparameter tuning. Model performance was assessed using the root mean squared error (RMSE) of the COSI scores. Model interpretation was performed using Shapley Additive Explanations. RESULTS: The data set comprised 1,286 patients across 3,523 listening situations. The best performing model was random forest with an RMSE of 0.80, found to be significantly better than the next best model (eXtreme gradient boosting with RMSE of 0.85, p < 0.01). The most important features in predicting hearing aid benefit were shorter duration of hearing aid use, higher pure-tone average in the better hearing ear, and younger age. CONCLUSION: We have developed a predictive model for hearing aid benefit that can also provide individualized explanations of model predictions. Predictive modeling could be a useful tool in assessing a patient's candidacy and predicted benefit from hearing aids.


Asunto(s)
Audífonos , Pérdida Auditiva Sensorineural , Pérdida Auditiva , Percepción del Habla , Humanos , Pérdida Auditiva/rehabilitación , Pruebas Auditivas , Encuestas y Cuestionarios , Medición de Resultados Informados por el Paciente , Pérdida Auditiva Sensorineural/rehabilitación
2.
Otol Neurotol ; 43(10): e1094-e1099, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36201555

RESUMEN

OBJECTIVES: In 2020, Advanced Bionics (AB) announced a recall of two cochlear implant (CI) models, the "HiRes Ultra" and "HiRes Ultra 3D", because of reports of hearing degradation. The present study examines clinical parameters and patient features in cases of device failure and evaluates outcomes after reimplantation. MATERIALS AND METHODS: A series of 52 patients implanted with the recalled devices experienced suspected device failure and subsequently underwent revision CI placement at a tertiary academic medical center between December 2019 and November 2021. RESULTS: Consonant-nucleus-consonant scores and individual phonemes increased significantly between patients' preoperative evaluation and primary cochlear implantation. Performance declined significantly before revision and recovered after revision CI placement. Similarly, pure-tone average thresholds improved between preoperative and primary CI, fell before revision surgery, and were corrected with revision implantation. As a group, patients reached their peak hearing performance significantly faster after revision CI (mean ± standard deviation, 53.4 ± 51.8 d) compared with their primary CI (mean ± standard deviation, 260.6 ± 245.9 d). Electrical field imaging performed by AB and device impedance measurements were found to be abnormal in the basally positioned electrodes (electrodes 9-16). CONCLUSION: Hearing performance degradation is significant in AB Ultra device failures and seems to be linked to the basal-most electrodes in the array. Revision outcomes have been robust, necessitating continued monitoring of affected patients and support for reimplantation procedures. LEVEL OF EVIDENCE: IV.


Asunto(s)
Implantación Coclear , Implantes Cocleares , Percepción del Habla , Humanos , Biónica , Pruebas Auditivas , Reoperación , Estudios Retrospectivos
3.
Neurosurgery ; 90(5): 506-514, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35229827

RESUMEN

BACKGROUND: Local management for vestibular schwannoma (VS) is associated with excellent local control with focus on preserving long-term serviceable hearing. Fractionated proton radiation therapy (FPRT) may be associated with greater hearing preservation because of unique dosimetric properties of proton radiotherapy. OBJECTIVE: To investigate hearing preservation rates of FPRT in adults with VS and secondarily assess local control and treatment-related toxicity. METHODS: A prospective, single-arm, phase 2 clinical trial was conducted of patients with VS from 2010 to 2019. All patients had serviceable hearing at baseline and received FPRT to a total dose of 50.4 to 54 Gy relative biological effectiveness (RBE) over 28 to 30 fractions. Serviceable hearing preservation was defined as a Gardner-Robertson score of 1 to 2, measured by a pure tone average (PTA) of ≤50 dB and a word recognition score (WRS) of ≥50%. RESULTS: Twenty patients had a median follow-up of 4.0 years (range 1.0-5.0 years). Local control at 4 years was 100%. Serviceable hearing preservation at 1 year was 53% (95% CI 29%-76%), and primary end point was not yet reached. Median PTA and median WRS both worsened 1 year after FPRT (P < .0001). WRS plateaued after 6 months, whereas PTA continued to worsen up to 1 year after FPRT. Median cochlea D90 was lower in patients with serviceable hearing at 1 year (40.6 Gy [RBE] vs 46.9 Gy [RBE]), trending toward Wilcoxon rank-sum test statistical significance (P = .0863). Treatment was well-tolerated, with one grade 1 cranial nerve V dysfunction and no grade 2+ cranial nerve dysfunction. CONCLUSION: FPRT for VS did not meet the goal of serviceable hearing preservation. Higher cochlea doses trended to worsening hearing preservation, suggesting that dose to cochlea correlates with hearing preservation independent of treatment modality.


Asunto(s)
Pérdida Auditiva , Neuroma Acústico , Radiocirugia , Adulto , Estudios de Seguimiento , Audición , Pérdida Auditiva/etiología , Pérdida Auditiva/prevención & control , Humanos , Neuroma Acústico/cirugía , Estudios Prospectivos , Protones , Radiocirugia/efectos adversos , Estudios Retrospectivos , Resultado del Tratamiento
4.
Otolaryngol Head Neck Surg ; 167(3): 465-468, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34609938

RESUMEN

During the COVID-19 pandemic, the utility of portable audiometry became more apparent as elective procedures were deferred in an effort to limit exposure to health care providers. Herein, we retrospectively evaluated mobile-based audiometry in the emergency department and outpatient otology and audiology clinics. Air conduction thresholds with mobile audiometry were within 5 dB in 66% of tests (95% CI, 62.8%-69.09%) and within 10 dB in 84% of tests (95% CI, 81.4%-86.2%) as compared with conventional audiometry. No significant differences were noted between mobile-based and conventional audiometry at any frequencies, except 8 kHz (P < .05). The sensitivity and specificity for screening for hearing loss were 94.3% (95% CI, 91.9%-96.83%) and 92.3% (95% CI, 90.1%-94.4%), respectively. While automated threshold audiometry does not replace conventional audiometry, mobile audiometry is a promising screening tool when conventional audiometry is not available.


Asunto(s)
COVID-19 , Audiometría/métodos , Audiometría de Tonos Puros/métodos , Umbral Auditivo , COVID-19/epidemiología , Humanos , Pandemias , Estudios Retrospectivos
5.
Neurology ; 97(7 Suppl 1): S64-S72, 2021 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-34230203

RESUMEN

OBJECTIVE: To systematically evaluate published patient-reported outcome measures for the assessment of hearing function and hearing-related quality of life (QoL) and recommend measures selected by the Response Evaluation in Neurofibromatosis and Schwannomatosis International Collaboration (REiNS) as endpoints for clinical trials in neurofibromatosis type 2 (NF2). METHODS: The REiNS Patient-Reported Outcomes Working Group systematically evaluated published patient-reported outcome measures of (1) hearing function and (2) hearing-related QoL for individuals with hearing loss of various etiologies using previously published REiNS rating procedures. Ten measures of hearing functioning and 11 measures of hearing-related QoL were reviewed. Measures were numerically scored and compared primarily on their participant characteristics (including participant age range and availability of normative data), item content, psychometric properties, and feasibility for use in clinical trials. RESULTS: The Self-Assessment of Communication and the Self-Assessment of Communication-Adolescent were identified as most useful for adult and pediatric populations with NF2, respectively, for the measurement of both hearing function and hearing-related QoL. Measures were selected for their strengths in participant characteristics, item content, psychometric properties, and feasibility for use in clinical trials. CONCLUSIONS: REiNS recommends the Self-Assessment of Communication adult and adolescent forms for the assessment of patient-reported hearing function and hearing-related QoL for NF2 clinical trials. Further work is needed to demonstrate the utility of these measures in evaluating pharmacologic or behavioral interventions.


Asunto(s)
Sordera/fisiopatología , Pérdida Auditiva/fisiopatología , Audición/fisiología , Neurofibromatosis 2/fisiopatología , Adolescente , Adulto , Niño , Sordera/diagnóstico , Humanos , Masculino , Neurilemoma/fisiopatología , Neurofibromatosis/fisiopatología , Medición de Resultados Informados por el Paciente , Neoplasias Cutáneas/fisiopatología
6.
Ear Hear ; 42(4): 982-989, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33577219

RESUMEN

OBJECTIVES: Hearing loss is the most common sensory loss in humans and carries an enhanced risk of depression. No prior studies have attempted a contemporary machine learning approach to predict depression using subjective and objective hearing loss predictors. The objective was to deploy supervised machine learning to predict scores on a validated depression scale using subjective and objective audiometric variables and other health determinant predictors. DESIGN: A large predictor set of health determinants from the National Health and Nutrition Examination Survey 2015-2016 database was used to predict adults' scores on a validated instrument to screen for the presence and severity of depression (Patient Health Questionnaire-9 [PHQ-9]). After model training, the relative influence of individual predictors on depression scores was stratified and analyzed. Model prediction performance was determined by prediction error metrics. RESULTS: The test set mean absolute error was 3.03 (95% confidence interval: 2.91 to 3.14) and 2.55 (95% confidence interval: 2.48 to 2.62) on datasets with audiology-only predictors and all predictors, respectively, on the PHQ-9's 27-point scale. Participants' self-reported frustration when talking to members of family or friends due to hearing loss was the fifth-most influential of all predictors. Of the top 10 most influential audiometric predictors, five were related to social contexts, two for significant noise exposure, two objective audiometric parameters, and one presence of bothersome tinnitus. CONCLUSIONS: Machine learning algorithms can accurately predict PHQ-9 depression scale scores from National Health and Nutrition Examination Survey data. The most influential audiometric predictors of higher scores on a validated depression scale were social dynamics of hearing loss and not objective audiometric testing. Such models could be useful in predicting depression scale scores at the point-of-care in conjunction with a standard audiologic assessment.


Asunto(s)
Depresión , Pérdida Auditiva , Adulto , Depresión/diagnóstico , Depresión/epidemiología , Pérdida Auditiva/diagnóstico , Pérdida Auditiva/epidemiología , Humanos , Aprendizaje Automático , Encuestas Nutricionales , Cuestionario de Salud del Paciente
8.
Otol Neurotol ; 41(9): 1163-1174, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32925832

RESUMEN

: This combined American Neurotology Society, American Otological Society, and American Academy of Otolaryngology - Head and Neck Surgery Foundation document aims to provide guidance during the coronavirus disease of 2019 (COVID-19) on 1) "priority" of care for otologic and neurotologic patients in the office and operating room, and 2) optimal utilization of personal protective equipment. Given the paucity of evidence to inform otologic and neurotologic best practices during COVID-19, the recommendations herein are based on relevant peer-reviewed articles, the Centers for Disease Control and Prevention COVID-19 guidelines, United States and international hospital policies, and expert opinion. The suggestions presented here are not meant to be definitive, and best practices will undoubtedly change with increasing knowledge and high-quality data related to COVID-19. Interpretation of this guidance document is dependent on local factors including prevalence of COVID-19 in the surgeons' local community. This is not intended to set a standard of care, and should not supersede the clinician's best judgement when managing specific clinical concerns and/or regional conditions.Access to otologic and neurotologic care during and after the COVID-19 pandemic is dependent upon adequate protection of physicians, audiologists, and ancillary support staff. Otolaryngologists and associated staff are at high risk for COVID-19 disease transmission based on close contact with mucosal surfaces of the upper aerodigestive tract during diagnostic evaluation and therapeutic procedures. While many otologic and neurotologic conditions are not imminently life threatening, they have a major impact on communication, daily functioning, and quality of life. In addition, progression of disease and delay in treatment can result in cranial nerve deficits, intracranial and life-threatening complications, and/or irreversible consequences. In this regard, many otologic and neurotologic conditions should rightfully be considered "urgent," and almost all require timely attention to permit optimal outcomes. It is reasonable to proceed with otologic and neurotologic clinic visits and operative cases based on input from expert opinion of otologic care providers, clinic/hospital administration, infection prevention and control specialists, and local and state public health leaders. Significant regional variations in COVID-19 prevalence exist; therefore, physicians working with local municipalities are best suited to make determinations on the appropriateness and timing of otologic and neurotologic care.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Otoneurología/organización & administración , Otorrinolaringólogos , Otolaringología/organización & administración , Neumonía Viral/epidemiología , Corticoesteroides/uso terapéutico , Betacoronavirus , COVID-19 , Centers for Disease Control and Prevention, U.S. , Humanos , Quirófanos , Pandemias , Equipo de Protección Personal/normas , Guías de Práctica Clínica como Asunto , Calidad de Vida , Medición de Riesgo , SARS-CoV-2 , Estados Unidos
9.
Otolaryngol Head Neck Surg ; 163(5): 1025-1028, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32718229

RESUMEN

Emergency departments (EDs) are a common location for patients to present with sudden hearing loss (SHL). Unfortunately, high-quality, rapid quantitative measurement of hearing loss is challenging. Herein, we aim to evaluate the accuracy of tablet-based audiometry in patients complaining of SHL. Prospective tablet-based testing was completed in the ED in patients complaining of SHL. Air conduction thresholds (ACTs) obtained via tablet-based audiometry were compared to same-day measurements with a clinical-grade audiometer. Hearing loss (HL) was defined as >20 dB ACT for any frequency. In participant-level analysis, 30+ dB HL in 3 consecutive frequencies was used to define SHL. In the ED, mobile audiogram ACTs were within 5 dB (77%) and 10 dB (89.6%) of those determined by conventional audiometry. The sensitivity and specificity for mobile audiometry to detect 3 or more consecutive thresholds with 30+ dB HL were 100% and 62.5%, respectively. Findings have implications for increasing access to high-quality audiometry.


Asunto(s)
Audiometría/instrumentación , Computadoras de Mano , Servicio de Urgencia en Hospital , Pérdida Auditiva Sensorineural/diagnóstico , Audiometría/métodos , Umbral Auditivo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad
11.
Laryngoscope ; 130(2): 507-513, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31095742

RESUMEN

OBJECTIVE: Electrically evoked auditory brainstem responses (EABR) guide placement of the multichannel auditory brainstem implant (ABI) array during surgery. EABRs are also recorded under anesthesia in nontumor pediatric ABI recipients prior to device activation to confirm placement and guide device programming. We examine the influence of anesthesia on evoked response morphology in pediatric ABI users by comparing intraoperative with postoperative EABR recordings. STUDY DESIGN: Retrospective review. METHODS: Seven children underwent ABI surgery by way of retrosigmoid craniotomy. General anesthesia included inhaled sevoflurane induction and propofol maintenance during which EABRs were recorded to confirm accurate positioning of the ABI. A mean of 7.7 ± 2.8 weeks following surgery, the ABI was activated under general anesthesia or sedation (dexmedetomidine) and EABR recordings were made. A qualitative analysis of intraoperative and postoperative waveform morphology was performed. RESULTS: Seven subjects (mean age 20.6 months) underwent nine ABI surgeries (seven primary, two revisions) and nine activations. EABRs were observed in eight of nine postoperative recordings. In three cases, intraoperative EABRs during general anesthesia were similar to postoperative EABRs with sedation. In one case, sevoflurane and propofol were used for intra- and postoperative recordings, and waveforms were also similar. In four cases, amplitude and latency changes were observed for intraoperative versus postoperative EABRs. CONCLUSION: Similarity of EABR morphology in the anesthetized versus sedated condition suggests that anesthesia does not have a large effect on far-field evoked potentials. Changes in EABR waveform morphology observed postoperatively may be influenced by other factors such as movements of the surface array. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:507-513, 2020.


Asunto(s)
Anestésicos/farmacología , Implantes Auditivos de Tronco Encefálico , Potenciales Evocados Auditivos del Tronco Encefálico/efectos de los fármacos , Implantación de Prótesis/métodos , Anestesia General , Anestésicos por Inhalación/administración & dosificación , Anestésicos Intravenosos/administración & dosificación , Sedación Consciente , Femenino , Humanos , Lactante , Masculino , Propofol/administración & dosificación , Estudios Retrospectivos , Sevoflurano/administración & dosificación
12.
Laryngoscope ; 130(5): 1299-1303, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31393603

RESUMEN

OBJECTIVES/HYPOTHESIS: To investigate the natural progression of hearing loss in patients with high-frequency hearing loss whose audiograms met the criteria for a hybrid cochlear implant (CI). STUDY DESIGN: Retrospective database review. METHODS: We retrospectively identified patients who met the criteria for a hybrid CI from our audiometric database. We also recorded the etiology of hearing loss in each patient and excluded patients with retrocochlear etiologies, those age <6 years, duration of observation <1 year, or those with a mixed or conductive hearing loss. We calculated the pre-CI progression of residual low-frequency (LF) hearing level in decibels per year and investigated the risk factor of the progression of hearing loss. RESULTS: A total of 1,083 ears of 944 patients were included in this study. The average rate of hearing loss progression for all etiologies was 1.70 ± 0.10 dB/yr at an average of 250 Hz, 500 Hz, and 1 kHz in the affected ear(s). The progression of hearing loss was 5.0 ± 0.93 dB/yr in patients with Meniere's disease and 3.5 ± 0.76 dB/yr in those with autoimmune disease, both of which were significantly faster than progression rates in other etiologies. In patients with idiopathic, genetic/hereditary, and congenital hearing loss, the progression of hearing loss was 1.46 ± 0.10 dB/yr. Patients with steeply sloping hearing loss experienced significantly faster progression in the ipsilateral ear compared to patients with another audiometric type. CONCLUSIONS: It is suggested that Meniere's disease, autoimmune-mediated inner ear disease, and steeply sloping hearing loss in the ipsilateral ear are risk factors for faster progression of residual LF hearing level. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:1299-1303, 2020.


Asunto(s)
Implantes Cocleares , Pérdida Auditiva , Adulto , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Pérdida Auditiva/cirugía , Humanos , Masculino , Persona de Mediana Edad , Selección de Paciente , Estudios Retrospectivos , Adulto Joven
14.
Hear Res ; 268(1-2): 105-13, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20553829

RESUMEN

The objective of this study was to develop reliable pediatric psychophysical methodologies in order to address the limits of frequency and electrode discrimination in children with cochlear implants. Discrimination was measured with a two-alternative, adaptive, forced choice design using a video game graphical user interface. Implanted children were compared to normal-hearing children in the same age ranges. Twenty-nine implanted children and 68 children with normal-hearing performed frequency discrimination studies at varying frequencies. Electrode discrimination was assessed in thirty-four implanted children at varying electrode locations and stimulation intensities. Older children had better frequency discrimination than younger children, both for implanted and hearing subjects. Implanted children had worse frequency discrimination overall and exhibited learning effects at older ages than hearing children. Frequency discrimination Weber fractions were smallest in low frequencies. Electrode discrimination improved with stimulus intensity level for older but not younger children at all electrode locations. These results support the premise that developmental changes in signal processing contribute to discrimination of simple acoustic stimuli. For implanted children, auditory discrimination improved at lower frequencies and with electrodes at higher intensity. These findings imply that spatial separation may not be the key determinant in creating discriminable electrical stimuli for this population.


Asunto(s)
Desarrollo del Adolescente , Desarrollo Infantil , Implantes Cocleares , Corrección de Deficiencia Auditiva , Personas con Deficiencia Auditiva/rehabilitación , Percepción de la Altura Tonal , Detección de Señal Psicológica , Estimulación Acústica , Adolescente , Factores de Edad , Envejecimiento , Estudios de Casos y Controles , Niño , Preescolar , Estimulación Eléctrica , Humanos , Discriminación de la Altura Tonal , Diseño de Prótesis , Psicoacústica , Reproducibilidad de los Resultados , Juegos de Video
15.
Indian J Otolaryngol Head Neck Surg ; 60(2): 106-11, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23120516

RESUMEN

A child with a cochlear implant is expected to achieve the successful outcome of facilitated perception of sound and more oral communication. To achieve this goal, ongoing intervention from a variety of professionals is required. These professionals may represent the disciplines of medicine, audiology, social work, education, and speech / language pathology. In India, cochlear implantation is available in only a few large cities. Here, the otolaryngologist will direct the cochlear implant program. Besides determination of medical candidacy, device implantation and medical management, the otolaryngologist is responsible to ensure that other aspects of cochlear implant management are implemented. This paper, the second of two that describe the multidisciplinary, team approach of the Pediatric Cochlear Implant Program of The Children's Hospital of Philadelphia (CHOP), in Pennsylvania, USA, discusses the non-medical aspects of cochlear implant post-implantation follow-up. The first article, previously published, discussed cochlear implant candidacy. The various speech tests used at CHOP for assessment are based on the English language. They may be translated into the regional Indian languages where the assessment and training can be carried out accordingly.

16.
J Am Acad Audiol ; 17(10): 722-32, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17153720

RESUMEN

Crystal Device Integrity Testing System (CITS), the first commercially available testing system of its type, allows rapid assessment of cochlear implant function by measuring averaged electrode voltages-the scalp-recorded fields generated by electrode currents. We describe our experience performing routine integrity tests on 44 pediatric cochlear implant patients using the CITS. We present our findings focusing on the monopolar and common ground scans to provide a framework from which CITS scans can be evaluated in the future. We also describe selected cases in which abnormal results using the CITS influenced clinical treatment, demonstrating the utility of performing routine integrity tests.


Asunto(s)
Implantes Cocleares , Niño , Implantes Cocleares/normas , Sordera/terapia , Conductividad Eléctrica , Electrodos , Falla de Equipo , Humanos
17.
J Assoc Res Otolaryngol ; 6(2): 160-70, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15952052

RESUMEN

Multielectrode cochlear implants rely on differential stimulation of the cochlear nerve for presenting the brain with the spectral and timing information required to understand speech. In implant patients, the degree of overlap among cochlear nerve fibers stimulated by the different electrodes constitutes the electrode interaction. Electrode interaction degrades the spectral resolution of the implant's stimulus. We sought to define electrode interaction in a cohort of pediatric cochlear implant subjects as a function of both stimulus intensity and electrode location along the array. The 27 pediatric subjects that completed the study were implanted with either the Clarion Hi-Focus array with or without positioner, the Nucleus 24 Contour array, or the Nucleus 24 Straight array. All but two of the patients had congenital hearing loss, and none of the patients had meningitis prior to the onset of deafness. The cochlear nerve response was measured with the electrically evoked compound action potential (ECAP). A forward masking protocol was used such that a probe stimulus electrode remained fixed while a preceding masker was moved across the array. Electrode interaction was estimated by measuring the unmasked probe response minus the masked probe response. Three probe locations and three probe intensities were examined for each subject. At all probe locations, electrode interaction increased as probe intensity increased (p < 0.05). Interaction at the basal probe was less than that at either the middle or apical probe locations (p < 0.05), and significant correlation found between probe distance from the basal end of the array and electrode interaction (p < 0.001). These results demonstrate that in this cohort of pediatric subjects, electrode interaction depended on both stimulus intensity and probe location. Implications of these findings on future implant array design and current implant fitting strategies are discussed. The impact of electrode interaction on implant performance is yet to be elucidated.


Asunto(s)
Artefactos , Implantes Cocleares , Electrodos , Niño , Preescolar , Estudios de Cohortes , Estimulación Eléctrica , Diseño de Equipo , Humanos , Lactante
18.
J Am Acad Audiol ; 15(9): 643-8, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15575338

RESUMEN

This paper describes an unusual Clarion 1.2 cochlear implant failure in order to demonstrate the need for the clinical availability of electrode voltage testing. The case report describes a patient with a Clarion 1.2 cochlear implant who exhibited poor auditory progress in spite of grossly normal impedances and electric field testing, and an appropriate educational and psychosocial environment. For a subset of electrodes, however, electrode voltage testing was abnormal. At explantation it was found that the epoxy that protects the connection between the electrode leads of the array and the output contacts on the internal controller had fractured. This failure was not associated with reported head trauma. This case report demonstrates the utility of and clinical need for electrode voltage testing as a helpful tool to diagnose internal device failure.


Asunto(s)
Implantes Cocleares , Pérdida Auditiva Sensorineural/terapia , Telemetría/métodos , Preescolar , Implantación Coclear , Implantes Cocleares/normas , Impedancia Eléctrica , Electrodos , Falla de Equipo , Femenino , Pérdida Auditiva Bilateral/terapia , Humanos , Reoperación
19.
Ear Hear ; 25(6): 528-38, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15604914

RESUMEN

OBJECTIVE: To characterize the amplitude growth functions of the electrically evoked compound action potential (ECAP) in pediatric subjects implanted with the Clarion HiFocus electrode array with respect to electrode position and the presence or absence of a Silastic positioner. Electrophysiologic growth function data are compared with HiResolution (HiRes) psychophysical programming levels. DESIGN: ECAP growth functions were measured for all electrodes along the implant's array in 16 pediatric subjects. Nine of the patients were implanted with a Silastic positioner, whereas seven had no positioner. ECAP thresholds and growth function slopes were calculated. Fifteen of the 16 patients had psychophysical threshold and maximum comfort levels available. Programming levels and ECAP thresholds were compared within and among the subjects. RESULTS: ECAP thresholds showed variability among patients, ranging from 178 to 920 nA at 32 musec pulse width. ECAP thresholds did not depend on electrode position along the cochlea but were lower in the presence of the Silastic positioner (p < 0.001). Thresholds determined with the masker-probe versus the alternating polarity paradigms revealed moderate (r = 0.76) correlation. Growth function slopes also showed considerable variation among patients. Unlike thresholds, slopes decreased from apical to basal cochlear locations (p < 0.001) but showed no difference between the absence and presence of the positioner. Programming levels in HiRes were correlated with ECAP threshold levels. When ECAP thresholds were adjusted for each patient by the difference between M level and ECAP threshold at electrode 9, however, overall correlation between the two measurements was excellent (r = 0.98, N = 224). CONCLUSIONS: In pediatric subjects with the Clarion HiFocus electrode, ECAP growth function thresholds appear to decrease with the presence of the Silastic positioner but are unaffected by electrode position along the array. Growth function slope, however, depends on electrode position along the array but not on the presence of the positioner. ECAP programming levels can reliably predict stimulus intensities within the patients' dynamic ranges, but considerable variability is seen between ECAP thresholds and HiRes programming levels.


Asunto(s)
Sordera/cirugía , Estimulación Eléctrica/instrumentación , Potenciales Evocados/fisiología , Prótesis e Implantes , Pruebas de Impedancia Acústica/métodos , Algoritmos , Umbral Auditivo , Biónica/instrumentación , Niño , Preescolar , Estudios de Cohortes , Sordera/diagnóstico , Electrodos Implantados , Diseño de Equipo , Femenino , Estudios de Seguimiento , Humanos , Masculino , Psicofísica , Índice de Severidad de la Enfermedad
20.
J Assoc Res Otolaryngol ; 4(1): 49-59, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12118364

RESUMEN

This study is one of a series that examines stimulus features important for cochlear implant function. Here, we examine effects of stimulus level. In subjects with cochlear implants, a number of psychophysical tests of temporal discrimination (pulse rate discrimination, gap detection, etc.) show marked improvement as a function of stimulus level through most or all of the dynamic range, while electrode-place discrimination can improve or degrade as a function of level. In this study, effects of these combined potential influences were studied by examining the effects of stimulus level on syllable identification. We tested two hypotheses: that syllable identification varies as a function of stimulus level and that level and electrode configuration interact in affecting syllable identification. We examined vowel and consonant identification as a function of stimulus level for bipolar and monopolar electrode configurations. We used experimental processor maps where upper and lower stimulation limits of each electrode pair were equated to eliminate confounding effects of dynamic range, which varies across subjects and electrodes. For each channel, stimulation amplitude was set to a fixed percentage of its dynamic range. Eight adult subjects with Nucleus CI24M implants were tested using the SPEAK processing strategy. With each electrode configuration, stimulus levels were tested from 0% to 90% of the dynamic range in nine steps. The effects on consonant and vowel identification were similar. Phoneme identification was usually better for monopolar than for bipolar stimulation. In the lower half of the dynamic range, syllable identification usually increased as a function of stimulus level. In the upper half of the dynamic range, syllable identification continued to increase as a function of level to 90% of the dynamic range for some subjects, while for others there was no appreciable change or a decrease as a function of level. Decreases in performance at high levels were more common with monopolar than bipolar stimulation. These results suggest that if speech processors are programmed to optimize level for each individual, speech perception performance could be improved.


Asunto(s)
Implantes Cocleares , Percepción del Habla/fisiología , Estimulación Acústica , Edad de Inicio , Anciano , Sordera , Discriminación en Psicología , Diseño de Equipo , Femenino , Humanos , Masculino , Microelectrodos , Persona de Mediana Edad
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