Light-adapted electroretinograms of eyes with cataract recorded using the HE-2000 system before and after mydriasis

To evaluate the effectiveness of the non-mydriatic mode of the HE-2000 electroretinogram (ERG) by comparing photopic ERGs of non-mydriatic versus dilated eyes. This retrospective study included patients with grade 2 cataracts between January and July 2022. Photopic ERGs were recorded using the HE-2000 system in mydriatic eyes with a 3 cd·s/m² flashing stimulus and in non-mydriatic eyes using the non-mydriatic mode with a 10 cd·s/m² stimulus. Amplitudes and implicit times of the a-wave, b-wave, and flicker ERG were compared using the Wilcoxon signed-rank test. Correlations between these parameters were analyzed using Spearman's rank correlation coefficient. In 54 eyes of 27 participants, the b-wave and flicker ERG amplitudes were lower in non-dilated eyes compared to dilated ones, with prolonged implicit times observed in non-dilated eyes (p < 0.0001). Despite these differences, both b-wave and flicker ERG amplitudes and implicit times showed strong correlations between dilated and non-dilated eyes (p < 0.01). However, the a-wave amplitude was more variable and less consistently measurable in non-dilated eyes. The HE-2000 system can provide clinically useful ERG recordings in non-dilated eyes, particularly for b-wave and flicker responses. Further validation under non-mydriatic conditions is required to establish its broader clinical utility.