RESUMO
Laryngeal evoked brainstem responses (LBRs) were recorded in normal human subjects in an attempt to develop a central laryngeal function test and enhance our understanding of neurolaryngologic disorders. The results showed that the human LBR consists of five positive peaks and five negative peaks reproducible within 10 ms after a vibratory stimulation to the superior laryngeal nerve (SLN). The waveform reproducibility was verified by blocking the SLN and topically anesthetizing the hypopharyngeal cavity. The morphology and latency of peak 5 were similar to results obtained in animal LBR experiments. It was concluded that a vibratory stimulation to the SLN was a noninvasive method to elicit far-field potentials from the central laryngeal pathway. These findings encourage further effort to establish normative data and explore clinical correlations.
Assuntos
Tronco Encefálico/fisiologia , Potenciais Evocados/fisiologia , Nervos Laríngeos/fisiologia , Laringe/fisiologia , Adulto , Anestésicos Locais/administração & dosagem , Animais , Doenças dos Nervos Cranianos/diagnóstico , Doenças dos Nervos Cranianos/fisiopatologia , Eletrodos , Potenciais Evocados/efeitos dos fármacos , Feminino , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Hipofaringe/efeitos dos fármacos , Hipofaringe/inervação , Doenças da Laringe/diagnóstico , Doenças da Laringe/fisiopatologia , Nervos Laríngeos/efeitos dos fármacos , Lidocaína/administração & dosagem , Masculino , Pessoa de Meia-Idade , Bloqueio Nervoso , Vias Neurais/fisiologia , Estimulação Física , Tempo de Reação , Reprodutibilidade dos Testes , VibraçãoRESUMO
Otolaryngological examinations, videostroboscopic image analysis, and laryngeal electromyography were used as a test battery for a critical evaluation in 80 patients. Vocal fold movements were categorized into mobility, restricted mobility, immobility with different positions, and overactive movement. Laryngeal electromyographic examinations were conducted in all patients, and the results were classified into normal, neuropathic, and myopathic patterns. The electromyographic data were integrated with videostroboscopic findings, interpreted with knowledge of biomechanical and electrophysiological mechanisms of the larynx, and correlated clinically with underlying diseases. It is suggested that neurolaryngological procedures are most clinically useful when dictated by a decision-making algorithm.