Frank Becquet, Xavier Zanlonghi, Jean-François Le Rouic, Didier Ducournau (Nantes, France)


To evaluate retinal macular function by multifocal electroretinogram (mfERG) in patients with idiopathic epiretinal membrane (ERM) or retinal vein occlusion (RVO).


In this retrospective comparative study, records of nine patients (9 eyes, mean age of 69 years) with unilateral ERM and records of ten patients (10 eyes, mean age of 67 years) with unilateral RVO were analyzed. LogMAR visual acuity and mfERG (responses from 61 stimulus elements) data were recorded and compared from eyes with ERM and RVO, and from the other healthy eye of each patient.


The mean visual acuity was statistically better in eyes with ERM than with RVO (ERM eyes = 0,47 ± 0,15; RVO eyes = 0,89 ± 0,26; p < 0,05) but, in the two groups, patients matched for age and lens status. The mean amplitudes of all components of the mfERG were significantly smaller for eyes with ERM or RVO compared to control ones. Significantly longer mfERG implicit times were present in ERM and RVO eyes compared to normal fellow eyes (p<0,01). No significant difference between ERM and RVO group were seen in term of mfERG implicit times.


A delay in mfERG implicit times was the main abnormality found in eyes suffering from ERM or RVO. This suggests that pathogenesis of ERM and RVO could implicate, at a different degree, the same ischemic mechanism.