The value of Flicker ERG B-wave implict time in macular degeneration

The B-wave of photopic 30 Hz flicker ERG can be used to study the altered response of the photoreceptor system in pathologic retinas. We had previously shown that its implicit time is a more reliable parameter than its amplitude to discriminate between normal and pathologic retinas. In this pilot study we confirm the observation that implicit time differs between healthy normal eyes (31.71 ±1.41 ms) and retinopathic eyes (38.16 ±3.97). Moreover, we show that implicit time also discriminates between eyes of patients affected by different forms of macular degeneration, such as atrophic AMD (34.54 ± 2.17) or neovascular MD (either age-related or myopic: 40.61 ± 3.13). Finally, we show that the contralateral eye of patients in which the fellow eye was affected by a neovascular retinal disease also shows an abnormal implicit time, suggesting that the physiological dysfunction may precede the morphologic,anatomic damage