Depolarizing focal macular electroretinogram pattern after photodynamic therapy in a patient with polypoidal choroidal vasculopathy.

摘要

Polypoidal choroidal vasculopathy (PCV) is an atypical form of age-related macular degeneration characterized by polypoidal structures consisting of dilatations at the ends of abnormal choroidal vascular networks in the inner choroid. Studies show that PCVs can be successfully treated by pho-todynamic therapy (PDT).It has been demonstrated that the neural elements in the macula contribute to the different components of focal macular electroretinograms (FMERGs). Relevant to this study, cones have been shown to transmit their signals to ON- and OFF-bipolar cells, and when these signals are blocked by glutamate analogs, a characteristic electroret-inogram (ERG) waveform arises, which is referred to as a "depolarizing pattern."1 In this waveform, the potential after the b wave does not return to the baseline level but remains elevated above the baseline.