Figure 4: Scatterplots showing the fERG threshold values recorded at different follow-up times (3, 9, and 15 months) plotted as a function of the corresponding baseline values. Diagonal lines in the plots indicate the equivalence between the values recorded at baseline and at a given followup. It can be noted that, at every followup, most values fall on the right of the diagonal line, indicating a decrease in threshold for the majority of patients.