The Compound Action Potential in Subjects Receiving a Cochlear Implant.
Otol Neurotol
; 37(10): 1654-1661, 2016 12.
Article
em En
| MEDLINE
| ID: mdl-27749750
ABSTRACT
HYPOTHESIS:
The compound action potential (CAP) is a purely neural component of the cochlea's response to sound, and may provide information regarding the existing neural substrate in cochlear implant (CI) subjects that can help account for variance in speech perception outcomes.BACKGROUND:
Measurement of the "total response" (TR), or sum of the magnitudes of spectral components in the ongoing responses to tone bursts across frequencies, has been shown to account for 40 to 50% of variance in speech perception outcomes. The ongoing response is composed of both hair cell and neural components. This correlation may be improved with the addition of the CAP.METHODS:
Intraoperative round window electrocochleography (ECochG) was performed in adult and pediatric CI subjects (nâ=â238). Stimuli were tones of different frequencies (250âHz-4âkHz) at 90âdB nHL. The CAP was assessed in two ways, as an amplitude and with a scaling factor derived from a function fitted to the response. The results were correlated with consonant-nucleus-consonant (CNC) word scores at 6 months post-implantation (nâ=â51).RESULTS:
Only about half of the subjects had a measurable CAP at any frequency. The CNC word scores correlated weakly with both amplitude (râ=â0.20, pâ<â0.001) and scaling factor (râ=â0.25, pâ<â0.01). In contrast, the TR alone accounted for 43% of the variance, and addition of either CAP measurement in multiple regression did not account for additional variance.CONCLUSIONS:
The underlying pathology in CI patients causes the CAP to be often absent and highly variable when present. The TR is a better predictor of speech perception outcomes than the CAP.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Audiometria de Resposta Evocada
/
Potenciais de Ação
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Cóclea
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Implante Coclear
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Monitorização Neurofisiológica Intraoperatória
Tipo de estudo:
Prognostic_studies
Limite:
Adult
/
Child
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Female
/
Humans
/
Male
Idioma:
En
Revista:
Otol Neurotol
Assunto da revista:
NEUROLOGIA
/
OTORRINOLARINGOLOGIA
Ano de publicação:
2016
Tipo de documento:
Article