RESUMO
The normal values of short-latent auditory evoked potentials (SAEP) are shown and a classification of the possible waves IV and V configuration is suggested. Examples of the use of SAEP in the differential diagnosis of some pathological conditions of the brain stem are discussed.
Assuntos
Tronco Encefálico , Cóclea , Neuroma Acústico/diagnóstico , Audiometria de Resposta Evocada , Encefalopatias/diagnóstico , Diagnóstico Diferencial , Potenciais Evocados , Humanos , Doenças do Labirinto/diagnóstico , Tempo de ReaçãoRESUMO
Out of 37 patients with verified neurinoma of the vestibulocochlear nerve 11 had essentially normal hearing and showed significant disorders of BERA (of the scissors type). This proved high sensitivity of computer audiometry (CA) applied to examine patients suspected for retrocochlear lesions. It is recommended to use CA when examining patients complaining of unilateral hearing impairment in order to rule out neurinoma of the 8th cranial nerve, especially at its early stage.
Assuntos
Potenciais Evocados Auditivos/fisiologia , Audição/fisiologia , Neuroma Acústico/fisiopatologia , Adolescente , Adulto , Audiometria/métodos , Feminino , Lateralidade Funcional , Perda Auditiva/diagnóstico , Perda Auditiva/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Neuroma Acústico/complicações , Neuroma Acústico/diagnóstico , Fatores de TempoRESUMO
An electrophysiological correlate of an effective enhancement of hearing aids (HA) can be emergence of a well differentiated V wave in three BERA tracings. The presence or absence of an unstable V wave is indicative of an inadequate HA enhancement; when comfortable loudness is exceeded, high-amplitude V wave with a shortened latent period (LP) as well as other waves that do not belong to BERA are recorded. An average LP value of V wave for different types of hypoacusis has been determined when the HA output is set at comfortable loudness. Other factors that have an impact on the V wave LP are also considered.