Estudo estatístico de valores normais do potencial visual evocado por padrão reverso. Contribuição à padronização do exame

Estudo estatístico de valores normais do potencial visual evocado por padrão reverso. Contribuição à padronização do exame

Autores:

Flávio R. L. Paranhos,
Augusto Paranhos,
Augusto Paranhos Jr.,
Renata L. Barbosa,
Arnaldo P. Cialdini,
Marcos P. Ávila

ARTIGO ORIGINAL

Arquivos Brasileiros de Oftalmologia

versão impressa ISSN 0004-2749versão On-line ISSN 1678-2925

Arq. Bras. Oftalmol. vol.61 no.3 São Paulo jun. 1998

http://dx.doi.org/10.5935/0004-2749.19980053

SUMMARY

Purpose:

To study the results of transient and steady-state pattern reversal visual evoked response (PVER) in 29 normal subjects examined in the city of Goiânia, Goiás, Brazil.

Methods:

The temporal frequency of reversal was 1.9 Hz (transient) and 7 Hz (steady-state). Five check-sizes (100, 50, 25, 12 and 6 min of arc.) were used for performing the steady-state PVER and only one (25 min of arc) for the transient. The latency considered was the one for the "P100" component of the 25 min of arc check size. Patients: 29 (mean age, 37.6 ± 16. 7 years), being 11 men and 18 women.

Results:

The steady-state PVER amplitude check size function curve showed the best results for the intermediate check sizes (50 and 25 min of arc) in both eyes (OU). The difference between eyes was not statistically significant (p > 0.01, Dunn method). The frequency distribution of the amplitudes was Gaussian only for 50 and 25 min of arc (W = 0.971, p = 0.638 (50 min OD); W = 0.965, p = 0.488 (25 min OD); W = 0.977, p = 0.791 (50 min OS); W = 0.975, p = 0.735 (25 min OS). The mean latency was 102.6 ± 3.8 ms (OD) and 103.0 ± 4.6 ms (OS) (p = 0.542), and thefrequency distribution was Gaussian (W = 0.959, p = 0.351 (OD) and W = 0.962, p = 0.407 (OS).

Conclusion:

Our results are similar to the literature and represent the first step for a satisfactory standardization of the normal values in our laboratory, as well as a reference for other Brazilian laboratories.

Keywords: Pattern visual evoked response (potential); Standardization

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