Application of rapid random stimulation (RRS) to visual evoked potentials in children.

The present study was performed to examine the effects of regular (1 Hz) and modified rapid random stimulation (RRS) (6 and 12 Hz) on visual evoked potentials (VEPs), by simultaneously recording negative waves around 100 ms, wave IV-latency, positive waves around 60 ms, wave III-latency, and amplitudes calculated from peak to peak, without causing impairment of visual acuity, in 44 patients aged 5-17 years. The wave IV-latencies of VEPs obtained by 6 and 12 Hz RRS were easily determined, and the latencies were not significantly changed compared to those obtained by previous 1 Hz regular stimulation. On the other hand, the amplitudes decreased in a frequency-dependent manner (1 < 6 < 12 Hz). These results were found to be similar in both preschool and school children. The examination time of VEPs determined by RRS is one-tenth shorter than that of 1 Hz regular stimulation. Thus, this method has the benefit of shortening the examination time, which decreases fatigue and inattention of the subjects, suggesting that modified RRS is a practically useful method for children.