Assessment of macular function by multifocal electroretinogram before and after epimacular membrane surgery.

PURPOSE: To evaluate macular function before and after successful surgical peeling of idiopathic epimacular membranes by means of multifocal electroretinogram (ERG) and measuring the first order Kernel. METHODS: Multifocal ERG of 10 patients (10 eyes) with idiopathic epimacular membrane were recorded before and after successful macular peeling. The retinal response densities of areas 1 and 2 were compared pre- and postoperatively and the functional state of the retina beneath the epimacular membrane was evaluated. The postoperative period was 3-6 months. RESULTS: Preoperatively, the electrical retinal response densities in the foveal and the perifoveal area were apparently decreased. After a mean postoperative period of 3 months the electrical response densities of the above areas improved. This improvement continued 6 months after the operation. CONCLUSION: In idiopathic epimacular membranes, the decrease in retinal electrophysiologic response was not limited to the fovea but also involved the perifoveal area. The electrical retinal response density of these areas gradually improved after peeling of the epimacular membrane.