Objective To analyze the symmetry of multifocal visual evoked potential (mfVEP) between both eyes in normal subjects. Methods The monocular mfVEP of both eyes in thirty-six normal subjects (72 eyes) was tested with VERIS Science 4.0. The stimulus was the pattern reversal dart array consisted of 60 sectors each included 16 black-white reverse patterns. The visual stimulation was controlled by the binary pseudo-random m-sequences and subtended approximately 25 degrees. Results There existed no statistically significant difference of P1 latencies and amplitudes between correspondent quadrant visual field of both eyes. The data difference of the ipsilateral quadrant visual fields was greater than those of the correspondent quadrant visual field. The comparison among four quadrant visual fields in right eye or left eye each showed that there was statistically significant difference of P1 latencies between the superionasal quadrant visual field and inferiotemporal or inferionasal quadrant visual fields. Conclusions The symmetry of normal mfVEP is more dominant in retina than that in visual cortex. (Chin J Ocul Fundus Dis, 2006, 22: 42-44)
Steady-state flsash visual evoked potentials (SFVEPs) of 30 Hz were recorded for 46 normal subjects (89 eyes )and 35 patients (51 eyes )with optic neuropathy. The visual acuities of 58.8%affected eyes were less than 0.1. The recorded waveforms were analyzed by discrete Foruier transform (DTF). The amplitudes and phases of fundamental response component and second harmonic were abstracted as characteristic values of the waveform.The total abnormal ratio was 80. 4%. The abnormal types showed the reduced amplitudes,reduced amplitude with phase change, the phases changes, and flat wave. The advantages of SFVEPs in clinical application were discussed. （Chin J Ocul Fundus Dis,1994,10:213-215）