Effect of repeat use and coating defects of gold foil electrodes on electroretinogram recording

Qualitative defects and resistances in 94 used gold foil electrodes were examined. The electrodes were divided into four groups of varying resistances and gold coating defects. Ten were randomly selected from each group to measure standard photopic electroretinograms (ERGS) in a normal subject. Ten new electrodes were used as controls. There was no significant difference among the electrode groups for ERG peak implicit times or amplitudes, although a slightly greater amplitude variability was observed for the groups with more defects. Provided the resistance of the electrode is low (< 5 Ω), its reuse at least; for ganzfeld ERGS appears warranted regardless of apparent coating defects.