The 30-Hz flicker cone ERG for monitoring the early course of central retinal vein occlusion

Purpose: Investigation of the full-field ERG (electoretinography) within 24 hours after the onset of symptoms in central retinal vein occlusion, and r epeated examination within the following days and weeks. Methods: Seven patients with central retinal vein occlusion were examined w ith full-field ERG within less than 24 hours after the onset of their sympt oms and every second to third day during the first 3 weeks. They were then followed for a period of time of six months. Results: The amplitudes as well as the implicit times in the 30 Hz flicker ERG changed considerably within the first three weeks. In the three patient s who developed rubeosis, the cone b-wave implicit times as well as the amp litudes were altered considerably. In the patients that did not develop rub eosis, the cone b-wave implicit times as well as the amplitudes in the 30 H z flicker ERG were more stable. Conclusion: The full-field cone ERG reflects the retinal function and the E RG parameters change considerably during the first weeks after the onset of the central retinal vein occlusion. The 30 Hz flicker ERG gives important information concerning the early development of the disease. The optimal ti me to do a predictive ERG could be after three weeks.