Fast oscillations of the electro-oculogram in a series of normal subjects.

Using a newly devised automated electro-oculograph, Nidek EOG-2, the fast oscillations (FOs) of the electro-oculogram were recorded in the 120 eyes of 60 normal subjects. We evaluated the normal means and variability of FO parameters, namely the "Rf" value, which is the average ratio in percentage of the maximum amplitude in the dark period (AD)/the minimum amplitude in the light period (AL), and the "df" value, which is the average difference between AD and AL during the FO measurement. No correlation with age was noted in the "Rf" value, although the lowest mean value of the "df" was detected in the twenties. Regarding sex, the mean levels of the "Rf" and "df" for female subjects were statistically higher than those for male subjects in the younger and global age groups. Some hormonal factor which can stimulate the metabolic activity of the retinal pigment epithelium might have caused this sexual difference.