Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 54
Filtrar
1.
Hear Res ; 450: 109068, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38936172

RESUMO

BACKGROUND & RATIONALE: In prior work using non-speech stimuli, children with hearing loss show impaired perception of binaural cues and no significant change in cortical responses to bilateral versus unilateral stimulation. Aims of the present study were to: 1) identify bilateral responses to envelope and spectral components of a speech syllable using the frequency-following response (FFR), 2) determine if abnormalities in the bilateral FFR occur in children with hearing loss, and 3) assess functional consequences of abnormal bilateral FFR responses on perception of binaural timing cues. METHODS: A single-syllable speech stimulus (/dα/) was presented to each ear individually and bilaterally. Participants were 9 children with normal hearing (MAge = 12.1 ± 2.5 years) and 6 children with bilateral hearing loss who were experienced bilateral hearing aid users (MAge = 14.0 ± 2.6 years). FFR temporal and spectral peak amplitudes were compared between listening conditions and groups using linear mixed model regression analyses. Behavioral sensitivity to binaural cues were measured by lateralization responses as coming from the right or left side of the head. RESULTS: Both temporal and spectral peaks in FFR responses increased in amplitude in the bilateral compared to unilateral listening conditions in children with normal hearing. These measures of "bilateral advantage" were reduced in the group of children with bilateral hearing loss and associated with decreased sensitivity to interaural timing differences. CONCLUSION: This study is the first to show that bilateral responses in both temporal and spectral domains can be measured in children using the FFR and is altered in children with hearing loss with consequences to binaural hearing.

2.
Hear Res ; 416: 108445, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35104716

RESUMO

OBJECTIVES: To identify whether mismatched bilateral cochlear implants compromise balanced stimulation of the two auditory nerves and establish asymmetric hearing in children. METHODS: Behavioural and electrophysiological measures were completed in 47 children receiving bilateral CIs in the same surgery (simultaneously): 27 children received a peri­modiolar N24RE array in one ear and a 422 anti-modiolar array in the other (experimental group) and 20 children received 2 peri­modiolar arrays (control group). Differences in current levels between the two devices were measured by electrically evoked compound action potentials (ECAPs) at the time of surgery. These data were compared with minimum and maximum comfortably loud levels programmed in each speech processor (T-levels, C-levels, respectively) after 12 months of bilateral CI use. Asymmetries in functional hearing between arrays were measured in open set speech perception testing between 3 to 5 years of CI use. RESULTS: Higher current levels were required from the anti-modiolar than peri­modiolar array to evoke balanced interaural ECAP amplitudes (mismatched group: mean ± SD difference: -9.9 ± 22.6; matched group: -0.8 ± 26.5). This difference was larger in the experimental group than control group (t = -2.51; p = 0.016) and remained constant with increases in current level from ECAP threshold to maximum amplitudes (dynamic range) in many but not all children in both groups. T and C-levels were poorly predictive of levels needed to evoke balanced ECAP amplitudes in children with mismatched devices (F(1, 312) = 1.3, p = 0.263). Speech perception scores were more asymmetric between ears in children using bilateral mismatched arrays (mean ± SD: 73.8 ± 16.4 at the peri­modiolar array; 57.7 ± 26.4 at the anti-modiolar array), compared to children with bilateral matched arrays (right ear: 78.0 ± 10.4; left ear: 74.9 ± 13.5). CONCLUSION: Higher current level requirements at the anti-modiolar array compared to the peri­modiolar array in children with bilateral mismatched CIs are not fully accounted for in device programming. Mismatched electrodes in children receiving bilateral cochlear implants increases the risk of asymmetric hearing.


Assuntos
Implante Coclear , Implantes Cocleares , Percepção da Fala , Criança , Implante Coclear/métodos , Nervo Coclear/fisiologia , Potenciais Evocados Auditivos/fisiologia , Humanos , Projetos de Pesquisa
3.
Int J Pediatr Otorhinolaryngol ; 135: 110109, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32480139

RESUMO

Cochleocele is an extrusion or herniation of the endosteum, through an incomplete stapes footplate, into the middle ear. The cochleocele may rupture resulting in a cerebrospinal fluid leak into the middle ear space causing a risk of menigitis. We report six cases of Incomplete Partition Type I with cochleocele which have all been successfully treated using a Totally Endoscopic Ear Surgery approach even during infancy. As the first two cases developed post-operative pseudomonas meningitis, preventative strategies are recommended.


Assuntos
Orelha Média/cirurgia , Endoscopia , Herniorrafia/métodos , Procedimentos Cirúrgicos Otológicos/métodos , Estribo/anormalidades , Vazamento de Líquido Cefalorraquidiano/prevenção & controle , Criança , Pré-Escolar , Orelha Média/diagnóstico por imagem , Feminino , Humanos , Lactente , Masculino , Meningites Bacterianas/etiologia , Procedimentos Cirúrgicos Otológicos/efeitos adversos , Complicações Pós-Operatórias , Infecções por Pseudomonas/etiologia
4.
HNO ; 67(10): 750-759, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31478064

RESUMO

OBJECTIVE: The characteristics of children with single-sided deafness (SSD) who become candidates for unilateral cochlear implantation (uCI) were identified. STUDY DESIGN: In all, 118 children with SSD presenting from 2013-2019 to a tertiary pediatric children's hospital were retrospectively assessed regarding candidacy for uCI. RESULTS: Of the 118 children, 103 had completed uCI candidacy assessment, while 15 were undergoing this assessment at the time of review. More than half of children did not go on to implantation (63/103, 61%), with the 2 main reasons being (1) half (31/63) did not meet candidacy criteria for implantation, most commonly due to cochlear nerve aplasia/hypoplasia (31/82 who were assessed with MRI, 38%) and (2) families (30/103; 29%) declined participation in the surgical arm of the trial. The most common etiologies of SSD in the 37/103 (36%) children who both met candidacy and consented to implantation were congenital cytomegalovirus (cCMV; 16/37, 43%), unknown (6/37, 16%), cochleovestibular anomaly and trauma (each 5/37, 14%). CONCLUSIONS: Many children with SSD who present for implant candidacy assessment do not ultimately receive uCI. Major factors contributing to noncandidacy are cochlear nerve aplasia and parental acceptance of the intervention. While approximately half of children with SSD in our cohort were candidates for implantation, only 1/3 of the total cohort proceeded with implantation with the main predictors of acceptability of this intervention being an etiology (i.e., cCMV) that carries risk of progressive deterioration in the better hearing ear or SSD that was sudden in onset. These findings provide important insight into this new population of cochlear implant users and the emerging acceptance of intervention in children with SSD.


Assuntos
Implante Coclear , Implantes Cocleares , Surdez , Perda Auditiva Unilateral , Criança , Implante Coclear/métodos , Perda Auditiva Unilateral/reabilitação , Humanos , Estudos Retrospectivos
6.
Clin Genet ; 92(1): 26-33, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27743452

RESUMO

The co-occurrence of hearing impairment and visual dysfunction is devastating. Most deaf-blind etiologies are genetically determined, the commonest being Usher syndrome (USH). While studies of the congenitally deaf population reveal a variable degree of visual problems, there are no effective ophthalmic screening guidelines. We hypothesized that children with congenital sensorineural hearing loss (SNHL) and vestibular impairment were at an increased risk of having USH. A retrospective chart review of 33 cochlear implants recipients for severe to profound SNHL and measured vestibular dysfunction was performed to determine the ocular phenotype. All the cases had undergone ocular examination and electroretinogram (ERG). Patients with an abnormal ERG underwent genetic testing for USH. We found an underlying ocular abnormality in 81.81% (27/33) of cases; of which 75% had refractive errors, and 50% of those patients showed visual improvement with refractive correction. A total of 14 cases (42.42%; 14/33) had generalized rod-cone dysfunction on ERG suggestive of Usher syndrome type 1, confirmed by mutational analysis. This work shows that adding vestibular impairment as a criterion for requesting an eye exam and adding the ERG to detect USH increases the chances of detecting ocular anomalies, when compared with previous literature focusing only on congenital SNHL.


Assuntos
Perda Auditiva Neurossensorial/fisiopatologia , Retinose Pigmentar/fisiopatologia , Síndromes de Usher/fisiopatologia , Doenças Vestibulares/fisiopatologia , Adolescente , Criança , Pré-Escolar , Eletrorretinografia , Olho/fisiopatologia , Feminino , Perda Auditiva Neurossensorial/complicações , Perda Auditiva Neurossensorial/diagnóstico , Humanos , Masculino , Retinose Pigmentar/complicações , Retinose Pigmentar/diagnóstico , Síndromes de Usher/complicações , Síndromes de Usher/diagnóstico , Doenças Vestibulares/complicações , Doenças Vestibulares/diagnóstico , Adulto Jovem
7.
J Laryngol Otol ; 130(11): 1007-1021, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27739380

RESUMO

OBJECTIVE: To compare stimulation parameters of peri-modiolar and anti-modiolar electrode arrays using two surgical approaches. METHODS: Impedance, stimulation thresholds, comfortably loud current levels, electrically evoked compound action potential thresholds and electrically evoked stapedial reflex thresholds were compared between 2 arrays implanted in the same child at 5 time points: surgery, activation/day 1, week 1, and months 1 and 3. The peri-modiolar array was implanted via cochleostomy in all children (n = 64), while the anti-modiolar array was inserted via a cochleostomy in 43 children and via the round window in 21 children. RESULTS: The anti-modiolar array had significantly lower impedance, but required higher current levels to elicit thresholds, comfort, electrically evoked compound action potential thresholds and electrically evoked stapedial reflex thresholds than the peri-modiolar array across all time points, particularly in basal electrodes (p < 0.05). The prevalence of open electrodes was similar in anti-modiolar (n = 5) and peri-modiolar (n = 3) arrays. CONCLUSION: Significant but clinically acceptable differences in stimulation parameters between peri-modiolar and anti-modiolar arrays persisted four months after surgery in children using bilateral cochlear implants. The surgical approach used to insert the anti-modiolar array had no overall effect on outcomes.


Assuntos
Estimulação Acústica , Implante Coclear/métodos , Implantes Cocleares , Perda Auditiva/cirurgia , Adolescente , Limiar Auditivo , Criança , Pré-Escolar , Cóclea/cirurgia , Impedância Elétrica , Potenciais Evocados Auditivos , Feminino , Perda Auditiva/etiologia , Humanos , Lactente , Masculino , Estudos Prospectivos , Janela da Cóclea/cirurgia , Estapédio/fisiopatologia , Resultado do Tratamento
8.
Cochlear Implants Int ; 15(1): 43-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24075736

RESUMO

OBJECTIVE: (1) Compare the non-device-related costs of bilateral simultaneous cochlear implantation (BSiCI) vs. unilateral, and (2) establish a dollar amount for potential cost savings in direct costs for BSiCI vs. sequential cochlear implantation (CI). METHODS: Data from all CI cases performed during the fiscal year 2010-2011 were retrospectively reviewed without exception. Fifty-four patients received unilateral CI and 36 received BSiCI. Demographics and data regarding direct costs associated with the operation and immediate in hospital post-operative period were collected. RESULTS: The total operating room (OR) time for unilateral and BSiCI was 3 hours 00 minutes and 4 hours 37 minutes, respectively, with a mean difference of 1 hour and 36 minutes (SD = 0 hours:06 minutes). The cost of OR and post-anesthetic care unit supporting staff was $3102 and $4240 for unilateral and BSiCI, respectively, with a mean difference of $1138 (SD = 216). Unilateral CI supplies totaled $1348 compared to $1822 for BSiCI supplies with an average difference of $438 (SD = 123). CONCLUSION: The total direct costs for a unilateral CI (excluding implantable device and surgeon fees) were $4362 compared to $5823 dollars for BSiCI. Simultaneous implantation can lead to a potential saving of $2901 compared to sequential implantation.


Assuntos
Implante Coclear/economia , Redução de Custos , Surdez/economia , Surdez/terapia , Custos Diretos de Serviços , Adolescente , Criança , Pré-Escolar , Implante Coclear/métodos , Implantes Cocleares/economia , Desenho de Equipamento , Feminino , Humanos , Masculino , Duração da Cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
9.
Cochlear Implants Int ; 12 Suppl 2: S8-14, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21917210

RESUMO

Bilateral cochlear implants (CIs) have been provided to children who are deaf in both ears with intent to promote binaural hearing. If it is possible to establish binaural hearing with two CIs, these children would be able to make use of interaural level and timing differences to localize sound and to distinguish between sounds separated in space. These skills are central to the ability to attend to one particular sound amidst a number of sound sources. This may be particularly important for children because they are typically learning and interacting in groups. However, the development of binaural processing could be disrupted by effects of bilateral deafness, effects of unilateral CI use, or issues related to the child's age at onset of deafness and age at the time of the first and second cochlear implantation. This research aims to determine whether binaural auditory processing is affected by these variables in an effort to determine the optimal timing for bilateral cochlear implantation in children. It is now clear that the duration of bilateral deafness should be limited in children to restrict reorganization in the auditory thalamo-cortical pathways. It has also been shown that unilateral CI use can halt such reorganization to some extent and promote auditory development. At the same time, however, unilateral input might compromise the development of binaural processing if CIs are provided sequentially. Mismatches in responses from the auditory brainstem and cortex evoked by the first and second CI after a long period of unilateral CI use suggest asymmetry in the bilateral auditory pathways which is significantly more pronounced than in children receiving bilateral implants simultaneously. Moreover, behavioural responses to level and timing differences between implants suggest that these important binaural cues are not being processed normally by children who received a second CI after a long period of unilateral CI use and at older ages. In sum, there may be multiple sensitive periods in the developing auditory system, which must be considered when determining the optimal timing for bilateral cochlear implantation.


Assuntos
Implante Coclear/métodos , Surdez/cirurgia , Potenciais Evocados Auditivos do Tronco Encefálico , Perda Auditiva Neurossensorial/cirurgia , Fatores Etários , Vias Auditivas/fisiopatologia , Limiar Auditivo , Criança , Pré-Escolar , Implante Coclear/efeitos adversos , Implantes Cocleares , Surdez/diagnóstico , Feminino , Seguimentos , Perda Auditiva Neurossensorial/diagnóstico , Humanos , Masculino , Percepção da Fala , Fatores de Tempo , Resultado do Tratamento
10.
Cochlear Implants Int ; 12(1): 21-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21756455

RESUMO

OBJECTIVE: Cochlear implant (CI) devices are the choice of treatment for individuals with severe to profound hearing loss. The CI devices provide the opportunity for children who are deaf to perceive sound by electrical stimulation of the auditory nerve, with the goal of optimizing oral communication. A natural benefit of acquiring hearing using CIs is the ability to hear, and perhaps enjoy, music. Music is a non-verbal auditory stimulus and a powerful tool for transmitting emotion. Identifying emotional cues is an important part of normal social development and communication and thus music may play an important role in establishing these skills during development. To date, it is not known whether children who use cochlear implants to hear can identify the emotional content carried in music. Our objective in the present study was to determine whether children who have been deaf from infancy and are experienced CI users have acquired the ability to identify emotion in musical phrases. METHOD: Study participants were 18 CI users (ages 7-13 years) who received right unilateral CIs (mean age at CI activation of 2.9 years) and 18 age-and gender-matched controls. Participants were asked to judge 32 brief musical excerpts as happy or sad by pointing to simple graphics of a smiling or frowning face. RESULTS: Children using CIs were able to correctly distinguish happy versus sad music well above chance levels, but performed more poorly on this task than their peers with typical hearing. Age at CI activation and time since CI activation were both uncorrelated with outcome measures. CONCLUSION: Children with CIs show the ability to perceive emotion in music but do so less accurately than typically hearing peers.


Assuntos
Percepção Auditiva/fisiologia , Implantes Cocleares , Surdez/cirurgia , Emoções/fisiologia , Música , Estimulação Acústica/métodos , Adolescente , Fatores Etários , Estudos de Casos e Controles , Criança , Implante Coclear/métodos , Surdez/diagnóstico , Expressão Facial , Feminino , Humanos , Masculino , Valores de Referência , Sensibilidade e Especificidade , Fatores Sexuais
11.
Brain Topogr ; 24(3-4): 204-19, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21479928

RESUMO

In the present paper, we review what is currently known about the effects of deafness on the developing human auditory system and ask: Without use, does the immature auditory system lose the ability to normally function and mature? Any change to the structure or function of the auditory pathways resulting from a lack of activity will have important implications for future use through an auditory prosthesis such as a cochlear implant. Data to date show that deafness in children arrests and disrupts normal auditory development. Multiple changes to the auditory pathways occur during the period of deafness with the extent and type of change being dependent upon the age and stage of auditory development at onset of deafness, the cause or type of deafness, and the length of time the immature auditory pathways are left without significant input. Structural changes to the auditory nerve, brainstem, and cortex have been described in animal models of deafness as well in humans who are deaf. Functional changes in deaf auditory pathways have been evaluated by using a cochlear implant to stimulate the auditory nerve with electrical pulses. Studies of electrically evoked activity in the immature deaf auditory system have demonstrated that auditory brainstem development is arrested and that thalamo-cortical areas are vulnerable to being taken over by other competitive inputs (cross-modal plasticity). Indeed, enhanced peripheral sight and detection of visual movement in congenitally deaf cats and adults have been linked to activity in specific areas of what would normally be auditory cortex. Cochlear implants can stimulate developmental plasticity in the auditory brainstem even after many years of deafness in childhood but changes in the auditory cortex are limited, at least in part, by the degree of reorganization which occurred during the period of deafness. Consequently, we must identify hearing loss rapidly (i.e., at birth for congenital deficits) and provide cochlear implants to appropriate candidates as soon as possible. Doing so has facilitated auditory development in the thalamo-cortex and allowed children who are deaf to perceive and use spoken language.


Assuntos
Encéfalo/crescimento & desenvolvimento , Implantes Cocleares , Surdez/terapia , Adolescente , Córtex Auditivo/crescimento & desenvolvimento , Córtex Auditivo/fisiologia , Vias Auditivas/crescimento & desenvolvimento , Vias Auditivas/fisiologia , Encéfalo/fisiologia , Tronco Encefálico/crescimento & desenvolvimento , Tronco Encefálico/fisiologia , Criança , Pré-Escolar , Surdez/fisiopatologia , Humanos , Lactente , Recém-Nascido , Plasticidade Neuronal/fisiologia
12.
Clin Neurophysiol ; 122(4): 823-33, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21094084

RESUMO

OBJECTIVE: Auditory development is disrupted without normal hearing but might proceed to some extent depending on the type and onset of deafness. We therefore hypothesized that activity in the auditory cortex would be highly variable in children who are deaf. METHODS: To answer this, activity in the deaf brain was evoked by electrical pulses from newly provided bilateral cochlear implants (CIs) in 72 children (n=144 responses). RESULTS: Responses were categorized by visual inspection into 3 main types which were validated by principal component cluster analyses; 49% had a negative amplitude wave similar to that previously reported in pre-term infants, 26% were dominated by a positive peak typical of responses in young normal hearing children and experienced paediatric CI users, 25% were novel multi-peaked responses. No significant demographic differences, including duration and onset of deafness, were found between response types. However, children with severe biallelic mutations of GJB-2 showed predominately negative peak type responses (79%) as compared with their peers without these mutations who had a more equal distribution between cortical response types. CONCLUSION: Cortical development in children who are deaf is heterogeneous but can be better predicted when the genotype is known to be a GJB-2 mutation. SIGNIFICANCE: Remediation of childhood deafness seeks to restore normal development and function of central auditory functions and thus may need to be tailored to account for effects specific to the aetiology of deafness.


Assuntos
Córtex Cerebral/fisiopatologia , Implantes Cocleares , Surdez/fisiopatologia , Surdez/terapia , Adolescente , Algoritmos , Alelos , Córtex Auditivo/fisiopatologia , Criança , Pré-Escolar , Análise por Conglomerados , Implante Coclear , Conexina 26 , Conexinas/genética , Interpretação Estatística de Dados , Estimulação Elétrica , Eletroencefalografia , Potenciais Evocados Auditivos/genética , Potenciais Evocados Auditivos/fisiologia , Feminino , Lateralidade Funcional/fisiologia , Lógica Fuzzy , Humanos , Lactente , Masculino , Mutação , Análise de Componente Principal , Análise de Ondaletas
13.
Cochlear Implants Int ; 11(2): 100-16, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19810023

RESUMO

The objective of this study was to evaluate the critical time period between the onset of sensorineural hearing loss and cochlear implantation with respect to normal voice production in children with post-meningitic hearing loss. Acoustic measures of voice production were obtained from ten paediatric cochlear implant recipients with post-meningitic hearing loss. Acoustic measures were obtained utilising the Multi-Dimensional Voice Program and Computerized Speech Laboratory (Kay Elemetrics Corp.). Measures were based on sustained phonation of the vowel /a/. Acoustic parameters included fundamental frequency, short- and long-term frequency perturbation, and short- and long-term amplitude perturbation. Measures of fundamental frequency and short-term frequency and amplitude perturbation were comparable to values of children with normal hearing. Long-term control of frequency was within normal limits for subjects with a period of auditory deprivation of less than four months. Measures of long-term amplitude perturbation were normal for all patients except those with cochlear ossification. Early restoration of auditory feedback with cochlear implantation, the absence of cochlear ossification, residual aided hearing following meningitis, and auditory-verbal therapy were identified as factors in preserving the long-term control of frequency and amplitude in the setting of post-meningitic hearing loss.


Assuntos
Acústica , Implante Coclear , Perda Auditiva Neurossensorial/etiologia , Perda Auditiva Neurossensorial/cirurgia , Meningite/complicações , Voz , Criança , Pré-Escolar , Retroalimentação Sensorial , Feminino , Audição , Auxiliares de Audição , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Neurossensorial/reabilitação , Humanos , Masculino , Fonação , Projetos Piloto , Fonoterapia , Fatores de Tempo
14.
Clin Neurophysiol ; 119(10): 2347-62, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18752993

RESUMO

OBJECTIVE: To determine if cortical responses evoked by a cochlear implant in children who are deaf differ from normal and to characterize these differences in children who achieve good versus fair speech perception outcomes post-implantation. METHODS: Late latency-evoked potential responses were recorded at 28 scalp locations in 16 children who were deaf from infancy and experienced cochlear implant users. Speech perception measures indicated that 8 had good scores and 8 had fair scores. In each child, responses were evoked by 36ms electrical pulse trains delivered from a single-implant electrode at the apical and basal ends of the array and by 36ms tone bursts (0.5, 2, and 6kHz). Responses to the tone bursts were also recorded in 14 age-matched children with normal hearing. RESULTS: We found (1) a dominant positive wave in all implant users and (2) a larger than normal negative amplitude peak in users with fair speech perception scores which had similar scalp topography to N1 but did not show the expected changes in amplitude with stimulus frequency. CONCLUSIONS: Late latency-evoked potential responses in children using cochlear implants reflect abnormal and/or immature patterns of cortical activity. SIGNIFICANCE: Limitations in auditory skills with a cochlear implant in children may be due to developmental processes in the cortex which are either slow to mature or which mature abnormally.


Assuntos
Córtex Auditivo/fisiopatologia , Implantes Cocleares , Surdez/patologia , Potenciais Evocados Auditivos/fisiologia , Estimulação Acústica/métodos , Adolescente , Artefatos , Percepção Auditiva , Mapeamento Encefálico , Estudos de Casos e Controles , Criança , Surdez/fisiopatologia , Surdez/cirurgia , Feminino , Humanos , Masculino , Psicoacústica , Tempo de Reação/fisiologia , Adulto Jovem
15.
Hear Res ; 233(1-2): 97-107, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17850999

RESUMO

Bilateral cochlear implants aim to restore binaural processing along the auditory pathways in children with bilateral deafness. We assessed auditory brainstem activity evoked by single biphasic pulses delivered by an apical or basal electrode from the left, right and both cochlear implants in 13 children. Repeated measures were made over the first 9-30 months of bilateral implant use. In children with short or long periods of unilateral implant use prior to the second implantation, Wave eV of the auditory brainstem response was initially prolonged when evoked by the naïve versus experienced side. These differences tended to resolve in children first implanted <3 years of age but not in children implanted at older ages with long delays between implants. Latency differences were projected to persist for longer periods in children with long delays between implants compared with children with short delays. No differences in right versus left evoked eV latency were found in 2 children receiving bilateral implants simultaneously and their response latencies decreased over time. Binaural interaction responses showed effects of stimulating electrode position (responses were more detectable when evoked by an apical than basal pair of implant electrodes), and duration of delay between implants (measured by latency delays). The trends shown here suggest a negative impact of unilateral implant use on bilateral auditory brainstem plasticity.


Assuntos
Implantes Cocleares , Surdez/fisiopatologia , Surdez/cirurgia , Potenciais Evocados Auditivos do Tronco Encefálico , Vias Auditivas/fisiopatologia , Tronco Encefálico/fisiopatologia , Pré-Escolar , Implante Coclear , Humanos , Lactente , Plasticidade Neuronal , Tempo de Reação , Fatores de Tempo
16.
Clin Neurophysiol ; 118(8): 1671-84, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17588811

RESUMO

OBJECTIVE: The role of apical versus basal cochlear implant electrode stimulation on central auditory development was examined. We hypothesized that, in children with early onset deafness, auditory development evoked by basal electrode stimulation would differ from that evoked more apically. METHODS: Responses of the auditory nerve and brainstem, evoked by an apical and a basal implant electrode, were measured over the first year of cochlear implant use in 50 children with early onset severe to profound deafness who used hearing aids prior to implantation. RESULTS: Responses at initial stimulation were of larger amplitude and shorter latency when evoked by the apical electrode. No significant effects of residual hearing or age were found on initial response amplitudes or latencies. With implant use, responses evoked by both electrodes showed decreases in wave and interwave latencies reflecting decreased neural conduction time through the brainstem. Apical versus basal differences persisted with implant experience with one exception; eIII-eV interlatency differences decreased with implant use. CONCLUSIONS: Acute stimulation shows prolongation of basally versus apically evoked auditory nerve and brainstem responses in children with severe to profound deafness. Interwave latencies reflecting neural conduction along the caudal and rostral portions of the brainstem decreased over the first year of implant use. Differences in neural conduction times evoked by apical versus basal electrode stimulation persisted in the caudal but not rostral brainstem. SIGNIFICANCE: Activity-dependent changes of the auditory brainstem occur in response to both apical and basal cochlear implant electrode stimulation.


Assuntos
Potenciais de Ação , Implantes Cocleares , Nervo Coclear/fisiopatologia , Surdez/fisiopatologia , Surdez/terapia , Estimulação Elétrica/métodos , Potenciais Evocados Auditivos do Tronco Encefálico , Tronco Encefálico/fisiopatologia , Criança , Pré-Escolar , Eletrodos , Feminino , Humanos , Masculino , Condução Nervosa , Tempo de Reação , Índice de Gravidade de Doença
17.
Cochlear Implants Int ; 7(3): 167-78, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18792384

RESUMO

The objective of this study was to report and discuss the management of chronic suppurative otitis media (CSOM) following cochlear implantation in children. The study was a retrospective review of 650 patients receiving an implant at two paediatric tertiary referral centres for cochlear implantation. Nine patients were identified who developed CSOM following cochlear implantation (incidence 1.38%). The mean time interval between implantation and symptom development was 3.66 years (range 2-8 years) and the mean time interval between implantation and CSOM surgery was 5.02 years (range 2.2-8 years). All patients presented with otorrhoea and/or abscess formation over the implant site. Two patients underwent a modified radical mastoidectomy and seven underwent a combined approach tympanoplasty, three of whom required posterior canal wall reconstruction with cortical bone and one with cartilage. In four cases it was possible to remove the cholesteatoma without removing the implant. All but two patients were fitted with a contralateral implant. In the explanted ears the cochlear implant electrode was cut at the cochleostomy site, which was then covered with muscle. Chronic suppurative otitis media following cochlear implantation may occur either as a result of a posterior canal wall defect related to surgery or possibly de novo. Attempts should be made to save the implant, but explantation with reimplantation of the contralateral ear may be the only option. In these cases the intracochlear part of the electrode array should be left in situ to facilitate possible future reimplantation. Surgical options for management of CSOM should be individualized and may include both canal-wall up and canal-wall down techniques. To reduce the incidence of CSOM following implantation the authors recommend: (1) prompt treatment and careful follow-up of patients with a history of otitis media with effusion, (2) avoidance of excessive thinning of the posterior canal wall during mastoidectomy and (3) reconstruction of any accidental trauma to the annulus or posterior canal wall during posterior tympanotomy.

18.
Int J Pediatr Otorhinolaryngol ; 68(4): 473-9, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15013616

RESUMO

OBJECTIVES: With the miniaturization of electronic devices, the demand and usage of button batteries has risen. As a result, button batteries are more readily available for young children to handle and potentially mishandle. They are frequently inadvertently placed by children in their ears or noses. Occasionally they are swallowed and lodged along the upper aerodigestive tract. METHODS: We outline the pathophysiology of button battery-induced trauma and present key radiological features of button batteries that are important in preventing delayed diagnosis after pediatric ingestion. RESULTS: Button batteries of all sizes have a distinctive double contour on radiographs. CONCLUSIONS: Button battery ingestion requires prompt diagnosis and removal. A high index of suspicion along with radiographs help assist with the diagnosis. Potential tragic complications can be averted with expeditious removal.


Assuntos
Orelha , Corpos Estranhos/diagnóstico por imagem , Corpos Estranhos/cirurgia , Nariz , Trato Gastrointestinal Superior , Feminino , Corpos Estranhos/complicações , Humanos , Lactente , Radiografia Torácica
19.
Arch Otolaryngol Head Neck Surg ; 127(9): 1053-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11556852

RESUMO

OBJECTIVES: To assess vocabulary development in children following cochlear implantation and to evaluate the effect of age at implantation on performance. DESIGN: Retrospective study (mean follow-up, 3(1/2) years). SETTING: Tertiary center. PATIENTS: Children with prelingual deafness provided with a cochlear implant between 1988 and 1999, who serially performed the Peabody Picture Vocabulary Test-Revised (60 patients) and the Expressive One-Word Picture Vocabulary Test-Revised (52 patients). The children were subgrouped into those receiving implants at younger than 5 years and at 5 years or older. OUTCOME MEASURES: Age-equivalent vocabulary test score and gap index (chronological age minus the age-equivalent score, divided by the chronological age at the time of testing) were calculated. For each test, the following were performed: calculation of rate of change for age-equivalent score; comparison of earliest and latest gap indices means (the cohort and intergroup and intragroup comparison); and multiple regression analysis demonstrating the effect of age at implantation, sex, communication mode, etiology of deafness, and residual hearing on the rate of vocabulary development. RESULTS: Expressive and receptive vocabulary development rates were 0.93 and 0.71 (age-equivalent scores per year), respectively. Subgrouped by age at implantation, the children's rates (for both vocabularies) were not statistically different (Peabody Picture Vocabulary Test-Revised, P =.90; Expressive One-Word Picture Vocabulary Test-Revised, P =.23). The global latest gap indices were significantly less than the earliest (Peabody Picture Vocabulary Test-Revised, P =.048; Expressive One-Word Picture Vocabulary Test-Revised, P<.001), indicating an improvement in age-appropriate vocabulary development over time. The age subgroups demonstrated similar results, except for the younger group's receptive gap index. On multiple regression analysis, the significant predictive variables were residual hearing (Expressive One-Word Picture Vocabulary Test-Revised) and male sex and oral communication mode (Peabody Picture Vocabulary Test-Revised). CONCLUSIONS: Children with cochlear implants developed their vocabularies at rates that were sufficient to prevent an increase in their gap indices as related to ideal scores at testing. A late age at implantation does not singularly preclude beneficial development of vocabulary.


Assuntos
Linguagem Infantil , Implante Coclear , Surdez/cirurgia , Vocabulário , Fatores Etários , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Estudos Retrospectivos
20.
Int J Pediatr Otorhinolaryngol ; 59(3): 181-6, 2001 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-11397499

RESUMO

Cricoid split is the procedure of choice in neonatal subglottic stenosis in many paediatric institutions. However, the post-operative care of these patients is a concern given the potentially lethal complications which can occur, in particular, self-extubation. We have been using the thyroid ala cartilage (TAC) reconstruction, a proven technique, as an alternative treatment for this disorder to avoid these complications. The purpose of this study was to compare the results of the TAC reconstruction for this patient population with the results of the cricoid split procedure previously reviewed at our own institution. Between January 1995 and December 1999, 17 patients that underwent the TAC reconstruction for neonatal subglottic stenosis were retrospectively reviewed. Of the 17 patients, two patients required tracheotomy prior to discharge from hospital. Fifteen patients were discharged from hospital with a safe airway without tracheotomy. There were only two minor complications. Compared with the cricoid split study, the success rate with TAC reconstruction was higher (88 vs 83%) and the major complication rate was lower (0 vs 9%). Factors associated with failed procedures may include prematurity, low birth and surgical weight and presence of severe GER. Those that failed required much greater resources in terms of post-operative care and length of hospital stay. The TAC reconstruction has replaced cricoid split in treatment of neonates with subglottic stenosis at our institution.


Assuntos
Laringoestenose/cirurgia , Cartilagem Tireóidea/cirurgia , Cartilagem Cricoide/cirurgia , Feminino , Humanos , Lactente , Recém-Nascido , Intubação Intratraqueal/efeitos adversos , Laringoestenose/etiologia , Masculino , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA