Visual evoked potentials in school children: a comparative study of transient and steady-state methods with pattern reversal and flash stimulation.
OBJECTIVE
Flash visual evoked potentials (VEPs) are commonly used in pediatrics, because children are sometimes uncooperative. We performed a comparative study of transient and steady-state VEPs with pattern reversal (PR) and flash (light-emitting diode, LED) stimulation.


METHODS
We recorded VEPs in 15 boys and 17 girls (aged 6-12 years) using 4 different stimulus conditions. The latency and amplitude of transient VEPs (T-VEPs) were measured. Steady-state VEPs (S-VEPs) were Fourier analyzed, and both the phase and amplitude of the major components were obtained.


RESULTS
The mean P100 latency of LED T-VEPs was longer and had a greater variability than that of PR T-VEPs. The LED T-VEPs had an amplitude of about double that of PR T-VEPs. The first harmonic response in the LED and second harmonic in PR were the major components of S-VEPs. The phases of PR and LED S-VEPs had narrow angular dispersions and amplitudes showed marked intersubject variability. Sex and age had no significant effect on both T-VEPs and S-VEPs.


CONCLUSIONS
Reproducible VEPs with 4 stimulus conditions can be obtained in school children. T-VEPs and S-VEPs are clinically useful because these methods provide complementary information.
Tomoda
Y
Y
Department of Pediatrics, School of Medicine, Fukuoka University, Japan.
Tobimatsu
S
S
Mitsudome
A
A
D001921:Brain / Q000502:physiology*; D002648:Child; D004569:Electroencephalography; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology