The effect of electrode positions on multifocal visual evoked potential / 中华眼底病杂志

ABSTRACT

Objective To compare the effect of electrode positions o n multifocal visual evoked potential(mf-VEP). Methods Ten healt hy individuals were tested with RETIscan multifocal VEP system 3.20, each indiv idual was tested with four electrode positions the active and reference electro de were placed 2.0 cm above and below the inion in Ch1;3.0 cm above and 4.5 cm below the inion in Ch2;2.0 cm on both right and left side of the inion in C h3 and 4.0 cm on both right and left side of the inion in Ch4. The summed ampli tudes of hemifield mf-VEP were analyzed and compared according to different ele ctrode positions. Results The difference among summed amplitud es of the upper or lower hemifield mf-VEP recorded with Ch1、Ch2、Ch3 and Ch4 w as statistically significant;and the difference between Ch2 and the other chann els was statistically significant too. The difference among summed amplitudes of the horizontal sites whose amplitudes were small when recorded with Ch2 and sum med amplitudes of the corresponding sites recorded with Ch3 and Ch4 were statist ically significant;and the difference between Ch4 and the other channels was st atistically significant too. Conclusions compared to Ch1、Ch3 and Ch4, Ch2 can make a better recording of mf-VEP. As for some sites, especi ally those along horizontal line, horizontal electrodes could improve the amplit udes of mf-VEP recorded with vertical electrodes,and Ch4 could do better to im prove the mf-VEP recorded with Ch2 than Ch3.