[The cerebral refractory time of visual evoked potentials in normal persons and in patients with multiple sclerosis]

29 normal persons at the age of 19 to 70 years were examined. Checker-board stimulation with a revolving mirror technique was used. The P2-latencies of the visually evoked potentials showed no relation to age. The changes of P2-latencies within the relative refractory period were so small, that a relative cerebral refractory time could not be determined. The absolute refractory time was at 16,7 +/- 11 ms. With MS-patients with retrobulbarneuritis pathologically lengthened absolute cerebral refractory times were found. The relative refractory time could not be determined. With patients with certain multiple sclerosis without anamnestic retrobulbarneuritis the determination of the absolute cerebral refractory time could improve the diagnostic accuracy in comparison to single stimulus examination.