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

Purpose 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. Methods This retrospective observational study included patients with grade 2 cataracts between January and July 2022. Photopic ERGs were recorded using the HE-2000 system in mydriatic eyes, using a standard 3 cd·s/m ² flashing stimulus, and non-mydriatic eyes, using the non-mydriatic mode with a 10 cd·s/m ² stimulus. Amplitudes and implicit times of the a-wave, b-wave, and flicker ERG were compared between both conditions using the Wilcoxon signed-rank test. Correlations between these parameters were analyzed using Spearman’s rank correlation coefficient. Results In 54 eyes of 27 participants, the b-wave and flicker ERG amplitudes were significantly lower in non-dilated eyes than in dilated ones, with prolonged implicit times in the former (p < 0.0001). Despite these differences, b-wave and flicker ERG amplitudes and implicit times strongly correlated between dilated and non-dilated eyes (p < 0.01). However, the a-wave amplitude was more variable and less reliably measured in non-dilated eyes. Conclusion The HE-2000 system can produce clinically useful ERG recordings in non-dilated eyes, particularly for b-waves and flicker responses. Further validation under non-mydriatic conditions is necessary to establish its clinical utility.