The effects of fundus photography on the multifocal electroretinogram

Purpose To determine the effect of flash fundus photography (FFP) on the multifocal electroretinogram (mfERG). Methods Ten subjects underwent mfERG testing on three separate dates. Subjects received either mfERG without FFP, mfERG at 5 and 15 min after FFP, or mfERG at 30 and 45 min after FFP on each date. The FFP groups received 10 fundus photographs followed by mfERG testing, first of the right eye then of the left eye 10 min later. Data were averaged and analyzed in six concentric rings at each time point. Average amplitude and implicit times of the N1, P1, and N2 peaks for each concentric ring at each time point after FFP were compared to baseline. Results Flash fundus photography did not lead to a significant change of amplitude or implicit times of N1, P1, or N2 at 5 min after light exposure. Conclusions These findings suggest that it is acceptable to perform mfERG testing without delay after performance of FFP.