Ledolter AA, et al. - The objective of this study is to determine whether the photoreceptor or post-photoreceptoral function is influenced in MacTel2 and could be detected utilizing electrophysiological examination. The outcome of this study suggests both scotopic (rod system dominated) and photopic ERGs (cone system) are consistent with post-photoreceptoral dysfunction. No electrophysiological evidence of dysfunction is seen at the level of the photoreceptor.