AIMS—To investigate the predictive value of the cone b-wave implicit time in the photopic compared with the scotopic 30 Hz flicker ERG for rubeosis in central retinal vein occlusion. METHODS—44 patients with a central retinal vein occlusion were examined with full field electroretinogram (ERG). RESULTS—The average implicit time in the photopic 30 Hz flicker ERG in patients who developed rubeosis (n=15) was 38.3 ms. In the patients who did not develop rubeosis (n=29) it was 31.3. The difference is statistically significant (p=0.0000000004). CONCLUSION—The photopic cone b-wave implicit time in the 30 Hz flicker ERG is a good predictor for rubeosis.
