RESUMO
PURPOSE: To introduce the clinical utility of the absolute value of the reconstructed waveform method in the analysis of multifocal visual evoked potential (mfVEP). METHODS: The mfVEP with 4-channel recording was performed using RETIscan(R) on 10 eyes of 10 normal subjects. Amplitudes were obtained from ring-shaped 6 areas and 4 sectors. The best visual evoked potential (VEP) response method and the absolute value of the reconstructed waveform method were compared in terms of analysis of the amplitudes. In order to assess the false positive rate of the examination, stimuli were administered with one-half of the cathode ray tube (CRT) monitor completely covered and the results were compared using 2 methods. RESULTS: The amplitudes in 6 areas and 4 sectors analyzed with the best VEP response method and the absolute value of the reconstructed waveform method showed no statistical difference (p > 0.05). The amplitude in the stimuli-blocked area of the absolute value of the reconstructed waveform method was smaller than that of the best VEP response method (p 0.05). CONCLUSIONS: The absolute value of the reconstructed waveform method has similar reproducibility and lower level of false positives relative to the best VEP response method. Therefore, it can be considered as a useful method in the analysis of the mfVEP.
Assuntos
Adulto , Feminino , Humanos , Masculino , Processamento Eletrônico de Dados , Potenciais Evocados Visuais/fisiologia , Seguimentos , Valores de Referência , Reprodutibilidade dos Testes , Retina/fisiologia , Estudos Retrospectivos , Campos VisuaisRESUMO
PURPOSE: To introduce the clinical utility of the absolute value of the reconstructed waveform method in the analysis of multifocal visual evoked potential (mfVEP). METHODS: The mfVEP with 4-channel recording was performed using RETIscan(R) on 10 eyes of 10 normal subjects. Amplitudes were obtained from ring-shaped 6 areas and 4 sectors. The best visual evoked potential (VEP) response method and the absolute value of the reconstructed waveform method were compared in terms of analysis of the amplitudes. In order to assess the false positive rate of the examination, stimuli were administered with one-half of the cathode ray tube (CRT) monitor completely covered and the results were compared using 2 methods. RESULTS: The amplitudes in 6 areas and 4 sectors analyzed with the best VEP response method and the absolute value of the reconstructed waveform method showed no statistical difference (p > 0.05). The amplitude in the stimuli-blocked area of the absolute value of the reconstructed waveform method was smaller than that of the best VEP response method (p 0.05). CONCLUSIONS: The absolute value of the reconstructed waveform method has similar reproducibility and lower level of false positives relative to the best VEP response method. Therefore, it can be considered as a useful method in the analysis of the mfVEP.